CN112118163B - System and method for energy and data transmission in an automation system - Google Patents

Abstract

The invention relates to a system for data transmission and energy transmission, comprising: a user and an additional user of the automation system, the user and the additional user being connected and in communication; voltage supply means for supplying a supply voltage to a user through a data bus; the user comprises a switching element for switching the user from a sleep state in which the user does not read the data signal issued by the further user to a read state in which the user reads the data signal issued by the further user; the switching element is configured to: determining whether a signal identifier issued by another user for initializing data transmission coincides with a predetermined signal identifier; and if the received signal identifier is consistent with the predetermined signal identifier, switching the user to a reading state; or if the received signal identifier is not consistent with the predetermined signal identifier, keeping the user in a dormant state; and the user is configured to resume from the read state to the sleep state.

Description

System and method for energy and data transmission in an automation system

Technical Field

The invention relates to a system for combined data and energy transmission in an automation system. The invention also relates to a user of a system for combined data and energy transmission in an automation system. The invention additionally relates to a method for combined data and energy transmission in an automation system.

Background

The combined energy and data transmission in an automation system has the following advantages: the wiring of the individual users of the automation system can be saved considerably. By supplying energy to the users of the automation system using the connections required for data transmission, the additional connections for energy supply of these users can be dispensed with.

In automation systems, the Power over Ethernet Standard (PoE) for combined energy and data transmission has proven to be feasible. However, for many applications in which, for example, comparatively simply constructed sensors, motors or actuators of an automation system are used, the PoE standard may be unnecessarily complex to design.

For such simply constructed applications, a solution is therefore sought which enables both a safe and reliable data transmission and a combined energy transmission, wherein the data transmission is however simply constructed according to requirements.

Disclosure of Invention

It can thus be seen that the invention is based on the tasks that: an efficient and simplified system for combined data transmission and energy transmission in an automation system is provided.

This object is achieved by means of the corresponding subject matter of the independent claims. Advantageous embodiments of the invention are the subject matter of the respective dependent claims.

According to one aspect of the invention, a system for combined data transmission and energy transmission in an automation system is provided, wherein the system comprises:

a user of the automation system and at least one further user, which are connected to one another by a data bus and are configured to communicate with one another by exchanging data signals via the data bus; and a voltage supply device for supplying a supply voltage to at least the subscriber via a data bus, wherein at least the subscriber comprises a switching element for switching the subscriber from a sleep state in which the subscriber does not read a data signal issued by the further subscriber to a read state in which the subscriber reads a data signal issued by the further subscriber, wherein the switching element is configured to: determining whether the signal identifier issued by the further user for initializing the data transmission corresponds to a predetermined signal identifier; and switching the user to a read state if the received signal identifier is consistent with a predetermined signal identifier; or if the received signal identifier does not correspond to the predetermined signal identifier, maintaining the user in a sleep state, and wherein the user is configured to resume from the read state to the sleep state. Thereby, the following technical advantages are achieved: a robust and simple system for combined data transmission and energy transmission in an automation system may be provided.

In the system, a subscriber and at least one further subscriber are connected to each other by means of a data bus and communicate with each other by exchanging data signals via the data bus. To this end, the user may be configured as a receiver of the data signal and the further user may be configured as a sender of the data signal. However, the user and the at least one further user may also be configured not only as a sender of the data signal but also as a receiver of the data signal. For this purpose, both the subscriber and the at least one further subscriber can have a transmitting/receiving unit and a switching element for checking the signal identifier.

Not only the user but also the at least one further user can be configured to generate a corresponding signal identifier.

At least the subscriber is supplied with a supply voltage via the data bus by means of a voltage supply device connected to the data bus. To this end, the user is correspondingly configured to: the supply voltage is applied via the data bus. Both the subscriber and the at least one further subscriber can be supplied with a supply voltage via the data bus.

The user may be at least in a sleep state or in a read state. In the sleep state, the user disregards signals transmitted via the data bus, which can be attributed not only to the data signals transmitted, but also to the supply voltage applied to the data bus. As long as the subscriber is in the dormant state, communication between the subscriber and at least one further subscriber is not possible, since the subscriber does not read the data signals emitted by the further subscriber. In the read state, the user can receive signals sent via the data bus and read these signals. Since the supply voltage is additionally attached to the data signal that is sent out for communication on the data bus, the following tasks are present for the user: a distinction is made between which of the signals transmitted via the data bus are data signals for communication between the user and the at least one further user and should therefore be read by the user, and which of the emitted signals should for example be associated with a supply voltage and therefore not be read.

To this end, the at least one further subscriber sends a signaling identifier to the subscriber for the purpose of initiating a data transmission between the at least one further subscriber and the subscriber. By means of the signaling identifier, the at least one further user signals to the user: after the signaling identifier, data signals are sent for the data transmission from the further user to the user, and the user accepts (aufzunehmen) and reads the data signals.

In order to identify the emitted signal identifier and to identify the emitted signal identifier as a signal identifier for initializing a data transmission, the subscriber has a switching element which is designed to determine whether the signal identifier emitted by the further subscriber corresponds to a predetermined signal identifier. If the emitted signal identifier is determined to be the same as the predetermined signal identifier, the user identifies the emitted signal identifier as a signal identifier for initializing a data transmission and interprets the received signal identifier as an initialization for an upcoming data transmission.

Hereinafter, data transmission is the successful transmission of a data signal by a sender and the successful reception and reading of the transmitted data signal by a receiver.

In the following, the data signals are voltage signals with corresponding voltage levels, which correspond to a logic one state 1 or a logic zero state 0, respectively, according to the signaling protocol.

In the following, a signal identifier is a sequence of specific voltage signals, wherein a voltage signal is a voltage level corresponding to a logic one state or a logic zero state. Thus, a semaphore is an unambiguous sequence of a logic one state and a logic zero state.

The switching element is further configured to: if the switching element recognizes that the received signal identifier corresponds to a predetermined signal identifier, the user is switched from the sleep state to the read state in order to realize the data transmission predicted by the signal identifier in this way.

After switching to the read state, the user can read the data signal transmitted by the further user for data transmission, so that a data-based communication between the two users is achieved. In this case, the further subscriber transmits a data signal for data transmission immediately after the emitted signal identifier.

In the event that the switching element recognizes that the received signal identifier does not correspond to the predetermined signal identifier, the switching element keeps the subscriber in the sleep state and no data transmission takes place between the subscriber and the further subscriber. This may occur, for example, if the emitted signal identifier is not determined for the respective subscriber, since no data transmission with this subscriber should be initiated. A random sequence of voltage levels, which cannot be attributed to the emitted signaling identifier but which result from random voltage fluctuations of the voltage applied to the bus or due to external disturbances, for example via capacitive or inductive coupling, and which merely look similar to the signaling identifier, can also be distinguished from the signaling identifier. Data transmissions that are initiated incorrectly due to such a voltage level sequence can be avoided in that the voltage level sequence received as a misinterpretation of a signal identifier is checked in respect of whether it is identical to a predetermined signal identifier.

If the data transmission between the subscriber and the at least one further subscriber is effected by the at least one further subscriber issuing a correct signal identifier and by the subsequent issuing of a data signal determined for the data transmission, the subscriber can resume the sleep state after the end of the data transmission between the subscriber and the further subscriber. In the sleep state, the user again does not read further voltage signals from the data bus until the user is switched back into the read state as a result of the signal identifier being emitted again.

The user may also have a transmit state in which the user is able to issue a corresponding data signal.

Thus, by switching the element and the signaling identifier issued by the further user, the user can be signaled in a simple manner: a data transmission between the user and the further user is imminent and the user therefore reads the signal sent via the data bus.

Therefore, the following problems can be eliminated: the supply voltage level or level change prevailing at any time due to the combined data transmission and energy transmission on the data bus is erroneously interpreted by the user as a data signal issued for data transmission. Thus, by switching the elements, the user can simply remain in the sleep state when there is no data transfer, while the user can be put into a read state when there is a data transfer between the user and the further user, in which the user reads the signals on the data bus.

Thus, by switching the user to the sleep state, the user is prevented from misinterpreting the voltage level applied to the data bus as the issued data signal. A data transmission without interference can also be achieved in that the user is put into a read state by means of the switching element and reads the emitted data signal.

As already mentioned, a signal identifier is a sequence of data signals corresponding to a separate sequence of logic one states and logic zero states. The signal identifier may comprise a 4-bit sequence, an 8-bit sequence, a 16-bit sequence, a 32-bit sequence, or a signal sequence of any length.

The predetermined signal identifier is a signal identifier that is separate for the user. Data transmission between the subscriber and the further subscriber is possible only if the signal identifier emitted by the further subscriber corresponds to the predetermined signal identifier of the subscriber. For automation systems with a plurality of users, a separate predetermined signaling identifier can be determined for each user, so that only data transmission with the one user can be effected when the determined signaling identifier is issued.

It is also possible to use predetermined signaling identifiers for communication with a plurality of users, so that a simultaneous data transmission by the plurality of users is possible if the generic signaling identifier is emitted.

According to one embodiment, the switching element is configured to: performing a logical operation; and based on the logical operation, comparing the received signal identifier with a predetermined signal identifier and determining whether the received signal identifier is consistent with the predetermined signal identifier.

Thereby, the following technical advantages are achieved: an unambiguous agreement of the received signal identifier with a predetermined signal identifier can be achieved. By this, it is achieved: the user is placed in the read state only if the user has received the correct signal identifier.

Thus, it is possible to avoid: even if no data transmission is encountered between the user and the at least one further user, the user is erroneously switched into the read state. It is also possible to avoid: when the data signals are either not determined for the user or the signal or voltage level read by the user does not correspond to a data transmission but fluctuates on the basis of the level of the supply voltage applied to the data bus, the user reads the data signals transmitted via the data bus and interprets them as a data transmission.

The logical operation enables an unambiguous identification of the received signal identifier.

Hereinafter, the logical operation may be a logical concatenation (Verknuepfung) of the respective logical one state and logical zero state of the semaphore. In this case, the logical connection may be an AND connection, an OR connection, a NOT connection, a NAND connection (Nicht-UND-Verknuepfung), a NOR connection, an XOR connection, or an XOR connection. By means of an evaluation of such a logical connection of the respective logic one state and logic zero state of the signal identifier, a correspondence of the received signal identifier with the predetermined signal identifier can be achieved.

Other logical operations suitable for achieving correspondence between a received signal identifier and a predetermined signal identifier are also contemplated.

Applying a logical operation to an accepted signal identifier may result in one logical true value or multiple logical true values. The agreement between the accepted signal identifier and the predetermined signal identifier can be achieved by a comparison of corresponding logical truth values which are obtained or are to be expected for the two signal identifiers. In this case, two signal identifiers should be interpreted as identical to one another if the application of a logical operation to the respective signal identifier results in an identical logical true value or a plurality of identical logical true values.

According to one embodiment, the switching element comprises: a shift register for registering the signal identifier of the further subscriber; a logic element coupled to the shift register for determining whether the registered signal identifier corresponds to a predetermined signal identifier; and a retention element coupled to the logic element for switching the user into a read state if the logic element determines that the accepted signal identifier is consistent with the predetermined signal identifier and for maintaining the user in a sleep state if the logic element determines that the signal identifier is not consistent with the predetermined signal identifier, wherein the logic element is configured to: performing a logical operation and based on the logical operation comparing the signal identifier registered by the shift register with a predetermined signal identifier and determining whether the registered signal identifier corresponds with the predetermined signal identifier.

Thereby, the following technical advantages are achieved: a technically simple and robust solution is provided for the switching element, which allows to determine an unambiguous agreement between the received signal identifier and the predetermined signal identifier.

The shift register is configured such that: registering the signal identifier issued by the at least one further subscriber.

In the following, the acceptance or reception of a signal identifier by the user and the registration of a signal identifier by the shift register are understood synonymously, so that the signal identifier registered by the shift register corresponds to the accepted signal identifier.

In order to register the signal identifier, the shift register has a plurality of Flip-Flop elements which are able to receive a logic one state or a logic zero state of the signal identifier, respectively. The shift register may comprise four, eight, sixteen, thirty-two or any number of flip-flop elements and may therefore be configured: register a 4-bit, 8-bit, 16-bit, 32-bit signal identifier or a signal identifier of any size. The number of logic one states and logic zero states of the signal identifier issued by the further subscriber corresponds to the number of flip-flop elements of the shift register of the switching element of the subscriber.

The logic element is connected to the shift register and is designed to receive a logic one state and a logic zero state of the signal identifier registered by the shift register and to check whether the signal identifier corresponds to a predetermined signal identifier by means of a logic operation. To this end, the logic gate may be configured as an and gate, an or gate, a not gate, a nand gate, a nor gate, an xor gate, or an xor gate.

The logic gate performs a logic operation corresponding to the AND gate type using the accepted logic one and zero states of the semaphore and determines one or more logic true values according to a truth table corresponding to the logic operation.

If applying a logical operation to an accepted signal indicator results in one or more logical true values corresponding to a logical true value of a predetermined signal indicator, then the logic element determines coincidence between the registered signal indicator and the predetermined signal indicator based on the one or more logical true values.

For example, the predetermined signal designator corresponds to a signal designator that results in a logical true value upon application of the determined logical operation. An accepted signal identifier that yields a logical true value when the same logical operation is applied is interpreted to coincide with a predetermined signal identifier.

Thus, depending on the complexity of the logic operation and the signal identifiers, an unambiguous agreement between two signal identifiers can be determined, wherein only signal identifiers having the same sequence of logic one states and logic zero states are determined to be in agreement.

The predetermined signal identifiers are determined by means of a shift register, which specifies the number of logic one states and logic zero states of the signal identifiers, and a corresponding design of the logic elements or logic gates as a corresponding sequence of logic one states and logic zero states, which sequence, when a corresponding logic operation is applied, yields a predetermined logic true value or a plurality of predetermined logic true values.

A holding element connected to the logic element switches the user into the read state on the basis of a correspondence between the registered signal identifier and the predetermined signal identifier, which is determined by the logic element. If the two signatures do not agree, the user is kept in a sleep state. The retention element also retains the user in a sleep state if the signal identifier is not asserted.

In this way, a simple switching element can be implemented which can switch the user into a read state or keep the user in a sleep state on the basis of the registered signal identifier, wherein the switching element can be implemented without an additional processor unit or microcontroller.

Thereby, the following technical advantages are achieved: a simple and robust switching element is provided which may ensure a data transmission with little interference.

According to one embodiment, the logic element is a logic gate, wherein the holding element comprises a Set-Reset Latch (S-R Latch) and a multiplexer.

The S-R latch may be connected with the S input of the S-R latch to the output of the logic gate. The S-R latch may be connected with the output of the S-R latch to the input of the multiplexer. The multiplexer may be connected to the data bus with the other input of the multiplexer. The output of the multiplexer may in turn be connected to the processor unit of the subscriber. A set-reset latch (S-R latch) is a set-reset flip-flop element known from the prior art.

If the logic element determines a coincidence between the registered signal identifier and the predetermined signal identifier and outputs a corresponding logical one true value or logical zero true value to the multiplexer, the multiplexer is switched to the on position and the connection between the data bus and the user's processor unit is allowed so that the data signals of the data bus can be read by the processor element.

After the data transfer is complete, the S-R latch may be reset through the R input of the S-R latch. Via this, a corresponding signal is transmitted to the multiplexer, so that the multiplexer interrupts the connection between the data bus and the processor element of the subscriber. To this end, the R input of the S-R latch may be connected to the user' S processor unit.

If the logic gate determines that the registered semaphore does not correspond to the predetermined semaphore, a corresponding one true value or zero true value is applied to the S input of the S-R latch, and the S-R latch sends a corresponding signal via the output to the multiplexer, causing the multiplexer to maintain the connection between the data bus and the user' S processor unit in an interrupted state.

According to one embodiment, the data bus is a differential data bus.

Thereby, the following technical advantages are achieved: a robust data bus with reliable signal transmission is provided. The differential data bus may be based on a serial interface, for example. For example, the differential data bus may be based on the serial interface RS 485. The UART protocol may also be used for data transmission. In this way, a technically simple and robust data transmission is achieved, which meets the requirements for data transmission for users having a simple technical design, such as sensors or actuators having a simple design.

According to one embodiment, the data signal emitted by the subscriber and/or by the further subscriber is encoded in a signal encoding without a direct current component.

Thereby, the following technical advantages are achieved: the data signals emitted for data transmission between these subscribers can be clearly separated from the supply voltage applied to the data bus. In the case of signal coding having a dc component in which the dc component of the signal level of the transmitted signal does not disappear, there are the following problems: a plurality of successive signals of successive logic one states cannot be unambiguously separated from the supply voltage applied to the data bus and therefore cannot be unambiguously identified as data signals. Signal coding without a dc component enables unambiguous identification of the emitted signal as a corresponding data signal even in the case of an applied supply voltage.

According to one embodiment, the subscriber and/or the further subscriber are coupled to the data bus by means of a galvanic coupling in order to draw a supply voltage.

Thereby, the following technical advantages are achieved: a robust electrical connection between the subscriber and/or the further subscriber and the data bus can be provided, which enables a combined data and energy transmission to the subscriber and/or the further subscriber via the data bus.

According to one embodiment, the system further comprises at least one filtering element for separating the data signal of the at least one user from the supply voltage, wherein the filtering element comprises a high-pass filter and/or a low-pass filter.

Thereby, the following technical advantages are achieved: a technically simple and secure separation between the supply voltage and the data signals of the data bus is achieved. By this, it is possible to avoid: the processor unit of the subscriber is loaded with a supply voltage applied to the data bus and the subscriber is therefore damaged. If the switching element switches the user into a read state in which the user is connected to the data bus via the processor unit on the basis of the registered signal identifier being recognized as coincident, only a voltage level having a frequency of the frequency range which is transparent to the filter element is applied to the processor element of the user. Thus, only the voltage level of the emitted data signal is applied to the processor element, with the frequency range of the filter element being suitably selected. The processor element can thus read the delivered data signal without the processor element being loaded with a supply voltage applied to the data bus.

According to a second aspect, the invention relates to a user of a system for combined data and energy transmission in an automation system, wherein the user is configured to: communication with at least one further user of the automation system by exchanging data signals via a data bus of the automation system and the supply voltage being applied by a voltage supply of the automation system via the data bus, and wherein the user comprises: a processor unit for reading data signals of further users of the automation system; a coupling element for coupling the subscriber to a data bus to receive a supply voltage; and a switching element for switching the user into a reading state in which the processor unit is able to read the received data signal and for maintaining the user in a sleep state in which the processor unit does not read the received data signal, wherein the switching element is configured to: determining whether the signal identifier issued by the further user for initializing the data transmission corresponds to a predetermined signal identifier; and switching the user to a read state if the received signal identifier is consistent with a predetermined signal identifier; if the received signal identifier does not correspond to the predetermined signal identifier, the user is maintained in a dormant state, and wherein the user is configured to resume to the dormant state.

Thereby, the following technical advantages are achieved: a user of the automation system is provided, which can be operated by means of a combined data transmission and energy transmission via a data bus of the automation system.

By means of the processor unit, the user is able to read the data signal issued by the at least one further user and thus perform a data transmission with the further user. By means of the coupling element, the subscriber is coupled to the supply voltage applied to the data bus and is therefore operated with the aid of this supply voltage.

The switching element is configured to: checking the received signal identifier; and switching the user into a read state if the signal identifier corresponds to a predetermined signal identifier. The switching element maintains the user in a sleep state if the switching element determines that the received signal identifier does not correspond to the predetermined signal identifier. After the end of the data transfer, the user can autonomously resume to the hibernation state.

By this, it is achieved: the user reads the signal emitted via the data bus only if the user is determined for data transmission with the at least one further user. During the time when no data transfer is encountered between these subscribers or the subscriber should not participate in the data transfer, the subscriber is in a sleep state and does not read any of the data signals applied to the data bus. By this, it is possible to avoid: the user incorrectly interprets the signals applied to the data bus as data signals and therefore an erroneous data transmission occurs.

By means of the combined data and energy transmission of the user via the data bus of the automation system, an automation system whose wiring is simplified can be implemented with the user in that additional wiring for the voltage supply to the user can be dispensed with.

The user is not distinguished as being the sender or the receiver in the data communication, but may send or receive data as appropriate. The user is at least able to receive and read data signals as a recipient in a data communication. However, the user may also be configured to send out a data signal as a sender.

According to one embodiment, the switching element is configured to: performing a logical operation; and based on the logical operation, comparing the received signal identifier with a predetermined signal identifier and determining whether the received signal identifier corresponds with the predetermined signal identifier.

Thereby, the following technical advantages are achieved: a user is provided which is designed for reliable data transmission and at which erroneous data transmission can be avoided. By means of a logical operation, the switching element can determine exactly whether the received signal identifier corresponds to a predetermined signal identifier. A misinterpretation of the accepted signal identifier as to whether it coincides with a predetermined signal identifier may be avoided.

As already described above, the logical operation may be an and connection, or connection, non-connection, nand connection, nor connection, xor connection, or xnor connection. Alternatively, the logical operation can also be a logical connection of a logical one state and a logical zero state of the semaphore. The logical operation should be chosen such that an unambiguous interpretation of the accepted signal identifier as to whether it coincides with a predetermined signal identifier is enabled.

As already described above, two signposts are determined to be identical if applying a logical operation to the two signposts results in the same logical true value.

According to one embodiment, the switching element comprises: a shift register for registering the signal identifier of the further subscriber; a logic element coupled to the shift register for determining whether the registered signal identifier matches a predetermined signal identifier; and a holding element connected to the logic element for switching the user into a read state if the registered signal identifier corresponds to the predetermined signal identifier and for holding the user in a sleep state if the registered signal identifier does not correspond to the predetermined signal identifier, wherein the logic element is configured to: a logical operation is performed and the registered signal identifier is compared with a predetermined signal identifier based on the logical operation and it is determined whether the registered signal identifier and the predetermined signal identifier coincide.

Thereby, the following technical advantages are achieved: a user is provided with a technically simple and reliable switching element which ensures that the user reads only the signals of the data transmission determined for the user on the data bus, irrespective of the signal or voltage level on the data bus which does not correspond to the data signal of the respective data transmission.

The shift register includes a plurality of flip-flop elements. Each flip-flop element is capable of accepting and temporarily storing a data signal corresponding to a logic one state or a logic zero state. The shift register can be designed with four, eight, sixteen, thirty-two or any number of flip-flop elements and can therefore register a signal identifier consisting of four, eight, sixteen, thirty-two or any number of logic one states and logic zero states. The number of flip-flop elements of the shift register determines the number of logic one states and logic zero states of the signal identifier.

If the sequence of logic one states and logic zero states issued over the data bus comprises a number of logic one states and logic zero states different from the number of flip-flop elements of the shift register, the corresponding sequence may be determined not to correspond to the predetermined signal identifier.

Based on the registered sequence of logic one states and logic zero states of the registered semaphore, the logic element is able to perform a logic operation and determine whether the registered sequence of logic one states and logic zero states of the semaphore corresponds to a predetermined sequence of logic one states and logic zero states of the semaphore.

For this purpose, the logic element may, for example, connect the respective logic one or zero states of the registered signal identifiers using the above-mentioned logic connections and, on the basis of the logic true values obtained therefrom, perform a check as to whether the registered signal identifiers correspond to predetermined signal identifiers. Based on the agreement of these two signposts determined by the logic element, the switching element switches the user into the read state if there is agreement.

Here, if applying the corresponding logical operation to the two identifiers yields one and the same logical true value or multiple and the same logical true values, there is a coincidence between the two identifiers.

For example, coincidence corresponds to a logical true value. The predetermined signal identifier thereby corresponds to a sequence of logic one states and logic zero states, which sequence leads to a corresponding logic true value if the corresponding logical connection of the logic element is applied to the sequence.

In this way, a technically simple and reliable switching element is achieved, which reliably switches the subscriber into the read state if the registered signal identifier corresponds to the predetermined signal identifier, and which keeps the subscriber in the sleep state if the registered signal identifier does not correspond to the predetermined signal identifier or no signal identifier is received or registered. No processor element or microprocessor is required for the user's switching element.

According to one embodiment, the logic element is a logic gate, wherein the retention element comprises an S-R latch and a multiplexer.

Thereby, the following technical advantages are achieved: a user with a switching element of simple design, robust and reliable is provided.

The logic gate may be an and gate, an or gate, a not gate, a nand gate, a nor gate, an xor gate, or an xor gate. The logic gate is configured to: a sequence of successive logic one states and logic zero states registered by the shift register is read in, and a logical operation corresponding to the logic gate is performed in pairs using the read-in logic one states and logic zero states. Based on the logical operation, the logic gate determines a logical true value or multiple logical true values.

The S-R latch is connected to the logic gate through the S input of the S-R latch. The S-R latch is connected to the control connection of the multiplexer via the output of the S-R latch. The multiplexer is connected to the data bus via an input and to the processor unit of the subscriber via an output.

If the logic gate determines that the registered signal identifier corresponds to the predetermined signal identifier, the logic gate outputs a corresponding true value to the S input of the S-R latch. The S-R latch in turn outputs a corresponding signal to the control input of the multiplexer. The multiplexer then switches the connection between the data bus and the processor element into the connected state. The processor element can then read the data signal from the data bus.

After the data transfer is complete, the S-R latch is reset. The S-R latch then sends a corresponding signal through the control input of the multiplexer, which then interrupts the connection between the data bus and the processor element. To reset the S-R latch, the R input of the S-R latch is connected to the processor element. Thus, the user can autonomously return to the hibernation state.

If the registered signal identifier does not correspond to the predetermined signal identifier, the signal applied by the logic gate to the S input of the S-R latch does not lead to a switching process of the S-R latch and therefore to a switching process of the multiplexer, so that the connection between the data bus and the processor element remains interrupted and the user is thus kept in a sleep state.

According to one embodiment, the coupling element is an inductive coupling element which enables inductive coupling of the user with a supply voltage provided on the data bus.

Thereby, the following technical advantages are achieved: a user with a robust and reliable coupling to the supply voltage provided via the data bus can be achieved.

According to one embodiment, the user further comprises at least one filter element for separating the data signal from the supply voltage, wherein the filter element comprises a high-pass filter and/or a low-pass filter.

Thereby, the following technical advantages are achieved: it can be ensured that only the voltage levels corresponding to the data signals issued via the data bus are applied to the processor unit of the subscriber. Loading the processor unit with a supply voltage and damage of the processor unit associated therewith can thus be avoided. Only a voltage level with a frequency within the permitted frequency range of the filter element is applied to the processor unit. Thus, with a corresponding selection of the frequency range of the filter element, it is possible to ensure that: only the voltage level of the data signal is applied to the processor unit.

According to one embodiment, the user also includes at least sensors, actuators or other devices for the automated system.

Thereby, the following technical advantages are achieved: a user with as wide a range of use as possible is provided.

According to a third aspect of the invention, a method for combined data transmission and energy transmission in an automation system is provided, wherein the automation system comprises: a subscriber and at least one further subscriber, which are connected to each other by a data bus and are configured to communicate with each other by exchange of data signals via the data bus; and voltage supply means for supplying a supply voltage to at least the subscriber via a data bus, wherein at least the subscriber comprises a switching element for switching the subscriber from a sleep state in which the subscriber does not read a data signal issued by the further subscriber to a read state in which the subscriber reads a data signal issued by the further subscriber, wherein the method comprises: in the identifier sending step, a signal identifier is sent by the further user to the user via the data bus for initializing data transmission; receiving the signal identifier by the switching element of the user in an identifier receiving step; in the checking step, checking, by the switching element, whether the received signal identifier coincides with a predetermined signal identifier; switching the user in the switching step to the reading state by means of the switching element if the received signal identifier corresponds to a predetermined signal identifier; in the data transmission step, the further user transmits a data packet to the user for data transmission; in the reading step, the user reads the data packet sent by the other user; after the data transmission is ended, restoring the user to a dormant state by the user in a restoring step; or if the accepted signal identifier does not correspond to the predetermined signal identifier, the user is kept in a sleep state by the switching element in the keeping step.

Thereby, the following technical advantages are achieved: a method for simple and robust combined data and energy transmission in an automation system is provided.

At least one user of the automation system is a user as described above, which has a switching element as described above, which is configured to: if the signal identifier emitted by at least one further user of the automation system corresponds to a predetermined signal identifier, the user is switched to the read state. To this end, at least one further subscriber transmits a corresponding signaling identifier via the data bus. The signaling identifier is used to initialize a data transmission between the user of the automation system and the at least one further user.

However, the user or the at least one further user is not distinguished between being a sender or a receiver in the data communication. The user being at least capable of receiving and reading data signals as a recipient in a data communication; and the at least one user is at least able to send data signals for data transmission to the user. However, the user may also be configured to: sending out a data signal as a sender; and the further user may be configured to: the data signal of the user is received and read. For this purpose, the at least one further user may have a switching element.

The signaling identifier is not part of the data transmission, but is merely an identifier that is sent to the respective subscriber before the actual data transmission, and should signal the subscriber: next, data transmission is expected.

In a next step, the switching element accepts the signal identifier and checks the accepted signal identifier as to whether it corresponds to a predetermined signal identifier. In the case of a coincidence of the two signal identifiers, the switching element switches the user into a read state in which the user is able to read the next data signal.

The signal identifier is not read by the user in the actual sense that the signal identifier is interpreted in content as in the case of a real data signal. The signal identifier is instead only checked for consistency with a predetermined signal identifier.

The actual sequence of logic one states and logic zero states that constitutes a semaphore is not recognized in a practical sense but is merely compared or checked with respect to whether a predetermined expected sequence of logic one states and logic zero states of the semaphore corresponds.

After the signaling identifier has been transmitted and the subscriber has accordingly switched to the read state, the at least one further subscriber transmits a data packet or a plurality of data packets to the subscriber for data transmission. The data packet or packets are the actual data transmission between the two users.

The user in the read state accepts the data packet or packets and reads the data signal of the data packet or packets. In this case, reading of the data signal means identifying the data signal and interpreting the content of the respective data signal accordingly. This is effected in accordance with a predetermined communication protocol and is carried out by the processor unit of the user.

The switching element does not contribute to the data transfer but merely serves to accept and identify the emitted signal identifier and to switch the user from the sleep state into the read state.

After the reception and reading of the data packets of the data transmission, the user carries out an operation corresponding to the data packet or the information of the data packets. After the last data packet is sent out and accepted, the data transmission between the at least one further subscriber and the subscriber is ended.

After the end of the data transmission between the subscriber and the at least one further subscriber, the subscriber reverts to the dormant state. In this state, the user cannot read other signals of the data bus. The user remains in the sleep state until the pending data transfer is initiated due to the reception of another signal identifier and the user is switched to the read state. If the subscriber is supposed to have a transmitting unit in addition to the receiving unit, the subscriber can likewise be switched from a sleep state into a transmitting state in which the subscriber can send out data signals for data transmission via the data bus.

If, however, the switching element determines that the accepted signal identifier does not correspond to the predetermined signal identifier, the switching element keeps the subscriber in the sleep state and no data transmission takes place between the subscriber and the further subscriber.

The switching element also maintains the user in a sleep state if no signature or a voltage signal not identified as a signature is received.

The method thus enables reliable data transmission, wherein incorrect interpretation of signals of the data bus by the user into data signals and the data transmission associated therewith having errors can be avoided.

According to one embodiment, the checking step further comprises: in the logical operation step, a logical operation is performed by switching elements; in the comparing step, the received signal identifier is compared with a predetermined signal identifier by the switching element based on the logical operation; and in the determining step, determining, by the switching element, whether the received signal identifier coincides with a predetermined signal identifier.

Thereby, the following technical advantages are achieved: an accurate determination of whether the transmitted signal identifier is consistent with a predetermined signal identifier is achieved using a logical operation.

The logical operation may be, for example, AND, OR, NOT, NAND, NOR, XOR, or XOR. Alternatively, the logical operation can also be another type of linking or execution rule which enables an exact and unambiguous agreement between the two signal identifiers.

As described above, the signal identifier comprises a sequence of logic one states and logic zero states. In the case of the implementation of the logical operation as one of the above-mentioned logical connections, the logical one states or the logical zero states of the signal identifiers can be correlated with one another in pairs using the respective operating rules of the respective logical connection. By means of the operating rules of the respective logic operation, a logic true value or a plurality of logic true values can be obtained for a sequence of logic one states and logic zero states of the signal identifier.

By means of the described application of a logical operation to the accepted signal identifier, a check can be made whether the accepted signal identifier and the predetermined signal identifier coincide. Determining whether the accepted signal identifier is identical to the predetermined signal identifier according to the corresponding logical true value or values derived from the logical operation, wherein an identity exists between two signal identifiers if an identical logical true value or values is/are obtained in case the logical operation is applied to both signal identifiers.

The predetermined signal identifiers correspond to a sequence of logic one states and logic zero states, which, when a specific logic operation is applied, result in a corresponding predetermined logic one true value or logic zero true value.

Two signal identifiers are interpreted as being identical to each other if the respective application of a logical operation to the respective signal identifier results in one and the same logical true value or multiple and the same logical true values.

By means of a corresponding embodiment of the corresponding logic operation, the consistent accuracy of the two signaling identifiers can be adapted to the corresponding requirements. Thus, by applying a logical operation, an accurate and reliable determination of whether two signal identifiers are consistent may be achieved.

According to one embodiment, the switching element includes a shift register, a logic element, and a holding element, wherein in the identifier accepting step, the shift register registers the signal identifier; wherein in the checking step, the logic element performs a logic operation in the logic operation step and compares the signal identifier registered by the shift register with a predetermined signal identifier based on the logic operation in the comparing step, and determines whether the registered signal identifier coincides with the predetermined signal identifier in the determining step; wherein in the switching step, the switching element switches the user into a reading state; and wherein in the maintaining step, the maintaining element maintains the user in a dormant state.

Thereby, the following technical advantages are achieved: a method is provided which enables a simple and reliable initialization of an upcoming data transmission between two users of an automation system.

As has been described above, the shift register is constructed from a plurality of flip-flop elements and is capable of temporarily storing a signal identifier composed of a plurality of logic one states and logic zero states. The number of flip-flop elements of the shift register is predetermined here by the number of logical one states and logical zero states which the signal identifier can have at most and/or must have at least.

The logic element is configured to: performing a logical operation as described above; and comparing the accepted signal identifier with a predetermined signal identifier based on the logical operation; and determining whether the registered signal identifier coincides with a predetermined signal identifier.

The holding member is configured to: if the signal identifiers are determined to be consistent, switching the user to a reading state; or if the signatures are determined to be inconsistent or not received, maintaining the user in a dormant state. In this way, a method can be achieved with a switching element which is simple and reliable in design and which enables reliable initialization of the forthcoming data transmission in that the switching element switches the user from a sleep state, in which no data transmission takes place, into a read state, in which data transmission can be achieved.

According to one embodiment, the logic element is a logic gate, wherein the retention element comprises an S-R latch and a multiplexer.

Thereby, the following technical advantages are achieved: a method is provided which enables an accurate and reliable initialization of a data transmission between two users of an automation system.

As described above, the logic gate may be an and gate, an or gate, a not gate, a nand gate, a nor gate, an xor gate, or an xor gate. By means of corresponding logic gates, a connection between the logic one state and the logic zero state of the registered signal identifier can be established in pairs and a logic true value or logic true values can be obtained correspondingly. Depending on the respective logic true value, it may be determined whether the registered signal identifier corresponds to the predetermined signal identifier as described above.

A signal corresponding to the accepted signal identifier corresponding to the predetermined signal identifier may be transferred to the S-R latch of the holding element which then switches the multiplexer of the holding element to the conducting position and thus establishes a connection between the data bus and the processor unit of the user. By means of the connection between the data bus and the processor unit of the user, the user can read the data signals issued via the data bus.

If the logic gate determines that the registered signal identifier does not correspond to the predetermined signal identifier, the logic gate sends a corresponding signal to the S-R latch, which in turn holds the multiplexer in an interrupt position in which the connection between the data bus and the user' S processor element is interrupted. By means of the connection of the processor element to the R input of the S-R latch, the connection between the data bus and the processor element can be disconnected after the end of the data transmission and the user can thus be restored to the sleep state.

The semaphore is only sent out for initializing data transmission. After the user has been switched into the read state after previously accepting the correct signal identifier, the user remains in the read state until the data transmission has resumed to the sleep state as a result of issuing a corresponding signal, for example a stop bit at the end of the last data packet of the data transmission.

In this way, a reliable data transmission between two users of the automation system can be achieved in that the users can be prevented from misinterpreting any signals on the data bus as a data transmission.

According to one embodiment, the data signal emitted by the subscriber and/or by the further subscriber is encoded in a signal encoding without a direct current component.

Thereby, the following technical advantages are achieved: a clearly interpretable data transmission is achieved. Due to the supply voltage applied to the data bus and the voltage level of the data bus associated therewith, which is also non-zero during times when no data transmission takes place, there is the problem of separating the varying level values due to the emitted data signals from the level values corresponding to the supply voltage. In the present case, the component-free signal coding makes it easy to separate the voltage level corresponding to the actual data signal from the voltage level of the supply voltage.

According to one specific embodiment, the voltage supply device loads the data bus with a supply voltage for the subscriber and/or the further subscriber, wherein the subscriber and/or the further subscriber draw the supply voltage by means of a current coupling, wherein the current coupling can be realized by means of an inductance acting as a low-pass filter.

Thereby, the following advantages are achieved: it is ensured that the user of the automation system is safely supplied with a supply voltage via the data bus. By means of this galvanic coupling, a secure coupling of the individual subscribers to the data bus can be achieved for receiving the supply voltage.

Drawings

Hereinafter, the present invention is described in detail according to preferred embodiments. In this case:

fig. 1 shows a schematic diagram of a system for combined data and energy transmission in an automation system according to an embodiment;

fig. 2 shows a schematic illustration of a switching element of a user of a system for combined data and energy transmission in an automation system according to an embodiment;

FIG. 3 shows a schematic diagram of an automation system with a system for combined data and energy transmission according to an embodiment;

FIG. 4 illustrates another schematic diagram of a system for combined data and energy transfer in an automation system, according to one embodiment;

fig. 5 shows a schematic illustration of a user of an automation system with a system for combined data and energy transmission in the automation system according to an embodiment;

fig. 6 shows a flowchart of a method for combined data and energy transmission in an automation system according to an embodiment;

fig. 7 shows a flow diagram of a method for combined data and energy transmission in an automation system according to a further embodiment;

FIG. 8a shows a voltage-time diagram of a data packet without a signal identifier according to a prior art signal transmission standard; and

fig. 8b shows a voltage-time plot of a packet with a signal identifier, according to an embodiment.

In the following, the same reference numerals may be used for the same features.

Detailed Description

Fig. 1 shows a schematic diagram of a system 100 for combined data and energy transmission in an automation system 300 according to an embodiment. For a better understanding, the system 100 is described in connection with the methods described in fig. 6 and 7 and the data signals, data packets, and signal identifiers described under fig. 8a and 8 b.

According to fig. 1, a system 100 for combined data and energy transmission in an automation system 300 comprises: a user 101 and at least one further user 103 of the automation system 300, which are connected to one another by a data bus 105 and are configured to communicate with one another by the exchange of data signals via the data bus 105; and a voltage supply device 107 for supplying at least the subscribers 101 with a supply voltage via the data bus 105, wherein at least the subscribers 101 comprise a switching element 109 for switching the subscribers 101 from a sleep state in which the subscribers 101 do not read data signals emitted by the further subscribers 103 to a read state in which the subscribers 101 read data signals emitted by the further subscribers 103, wherein the switching element 109 is configured to: determining whether the signal identifier issued by the further user 103 for initializing the data transmission corresponds to a predetermined signal identifier; and if the received signal identifier corresponds to a predetermined signal identifier, switching the user 101 to a read state; or if the received signal designator does not correspond to the predetermined signal designator, maintaining the user 101 in a dormant state, and wherein the user 101 is configured to revert from the read state to the dormant state.

In fig. 1, a system 100 is constructed with one subscriber 101 and three further subscribers 103, which are connected to one another via a data bus 105. The user 101 and the three further users 103 are constructed identically and each have a switching element 109, a processor unit 111, a filter unit 113 and a second filter unit 115. The user 101 and the three further users 103 also each have a transmitting/receiving unit 117 and are therefore configured to: not only data signals for data transmission are sent out, but also data signals for data transmission are received through the data bus 105.

The data bus 105 is connected to a voltage supply 107, which supplies the user 101 and the further user 103 with a supply voltage. The user 101 and the further user 103 are configured to: is operated by means of this supply voltage supplied via the data bus 105.

Alternatively, an additional filter unit 113 (not shown in the figure) may be connected between the voltage supply 107 and the data bus 105, which additional filter unit may prevent the data signal from being attenuated by the voltage supply 107.

The system 100 in fig. 1 can be understood as a closed automation system 300, wherein one of the users 101 or the further users 103 assumes the function of a system control or bus master and is designed to issue corresponding commands and operating commands to the remaining users 101 and the further users 103 for operating the automation system 300.

Alternatively, the system 100 in fig. 1 can be designed as a closed part of an automation system 300, as is shown in fig. 3. In fig. 1, such a connection to the superordinate automation system 300 is not shown, since this is of no importance for describing the operating principle of the system 100. For a description of the relationship of the system 100 to the upper level automation system 300, reference is made to the description of fig. 3.

The user 101 and the three further users 103 of fig. 1 may be interpreted as equally entitled users of the system 100, each of which is equally authorized to send and receive data signals for data transmission between these users. Alternatively, the user 101 or one of the three further users 103 can also assume the function of a bus master, while the further users of the system 100 can be driven to perform data transmission and to carry out corresponding operations as the corresponding data signals are emitted. The functionality of the subscriber 101 or of the further subscriber 103 within the system 100 is irrelevant for the operating principle of the system 100, so that in the following the assignment of the individual system subscribers as bus masters or bus slaves should be omitted.

By means of the switching element 109, the subscriber 101 and the three further subscribers 103 can be placed in a sleep state in which the subscriber 101 and the further subscribers 103 do not read the signals transmitted via the data bus 105.

In the sleep state, neither the voltage level of the supply voltage applied to the data bus 105 nor the voltage level to be attributed to the emitted data signals is taken into account by the user 101 and the further user 103. Thus, by the sleep state, it is avoided: even if the voltage level or level fluctuations of the voltage applied to the data bus 105 should not be attributed to data transmission, but rather they originate, for example, from supply voltage fluctuations or external disturbances, for example, disturbances in the capacitive or inductive coupling, the user 101 and the further user 103 interpret the respective voltage level or level fluctuations applied to the data bus 105 as data signals determined for data transmission. Such misinterpretation of the voltage levels applied to the data bus as corresponding data signals is problematic especially during times when the data bus 105 is not driven.

In the following, the working principle of the system 100 and the switching element 109 and the cooperation of the switching element 109 with other components of the respective user are described on the basis of the user 101 and one further user 103.

For simplicity of illustration of the system 100, the user 101 is considered as a recipient of data transmission between the user 101 and the further user 103, and one of the further users 103 is considered as a sender of data transmission between the user 101 and the further user 103. Since in the embodiment of the system 100 of fig. 1 each of the users 101, 103 has a transmitting/receiving unit 117, each of the users 101, 103 can act not only as a sender but also as a receiver.

Further, the system 100 should not be limited to communication between only two users of the system 100. Rather, communication is also possible between a plurality of users of the system 100, wherein a user 101 acting as a sender or a further user 103 sends a corresponding data signal for data transmission to a plurality of users acting as receivers of the system 100.

In this case, the user acting as the receiving party is able to receive the data signals sent by the sending party and to read them in accordance with the steps described above. The users 101, 103 acting as recipients can also: after receiving the data signal transmitted for the data transmission, a corresponding response message is sent in the form of the transmitted data signal to the user acting as a sender in the previous data transmission. The users 101, 103 of the system 100 may be arranged in a master-slave hierarchy, under which one user 101, 103 of the system 100 takes the role of a system master, while the remaining users 101, 103 take the role of system slaves. Alternatively, the users 101, 103 may operate as peer users of the system 100.

Since in the exemplary embodiment of the system 100 described in fig. 1 the user 100 and the further user 103 are configured identically, the description of the operating principle of the switching element 109 and the further components of the user 101 cited below can be transferred analogously to the further user 103 of the system 100.

The switching element 109 is configured to: the user 101 is switched from a sleep state to a read state in which the user 101 can read data signals issued over the data bus 105. For this purpose, the switching element 109 is connected to the transmitting/receiving unit 117 and the processor unit 111 of the user 101 according to the embodiment shown in fig. 1. The transmitting/receiving unit 117 is in turn connected to the data bus 105 via a second filtering unit 115.

According to one specific embodiment, the filter unit 113 can be designed as a low-pass filter which is only passable for the supply voltage and enables the coupling of the user 101 to the supply voltage applied to the data bus 105.

The second filtering unit 115 may include a high pass filter that can pass only signals of a predetermined frequency range. Preferably, the predetermined frequency range corresponds to the frequency range of the data signal emitted by the further user 103. Thus, it is possible to ensure that: only the voltage level of the transmitted data signal is applied to the processor unit 111 which is connected to the filter unit 113 via the switching element 109 and the transmit/receive unit 117, and the processor unit 111 is thus protected against loading of the supply voltage and damage to the processor unit 111 associated therewith.

The data signals emitted via the data bus 105 are forwarded to and accepted by a transmitting/receiving unit 117 of the subscriber 101 via a filtering unit 115. If the switching element 109 is in the read state, the data signal received by the transmitting/receiving unit 117 is forwarded to the processor unit 111 and read by the processor unit. If the switching element 109 is in the sleep state, the connection between the transmitting/receiving unit 117 and the processor unit 111 is interrupted and the processor unit 111 does not read the received data signal.

If the subscriber 101 is in the sleep state, the subscriber 101 can be switched into the read state by means of the switching element 109 for initializing a data transmission with at least one further subscriber 103. To this end, for initializing the data transmission, a signal identifier is emitted by at least one further subscriber 103 via the data bus 105 and received by the transmit/receive unit 117 of the subscriber 101 and forwarded to the switching element 109.

The switching element 109 is in turn designed to determine whether the received signal identifier corresponds to a predetermined signal identifier. If the received signal identifier corresponds to a predetermined signal identifier, the switching element 109 switches the user 101 into the reading state, whereby the connection between the transmission/reception unit 117 and the processor unit 111 is enabled by the switching element 109 and the processor unit 111 can read the next data signal received by the transmission/reception unit 117.

In this case, the signal identifier may be, as shown in fig. 8b, a sequence of successively transmitted data signals, which correspond to a logic one state and a logic zero state, respectively.

In order to check the received signal identifier by means of the switching element 109, the switching element 109 can be designed to: a logical operation is performed and it is determined whether the received signal identifier coincides with a predetermined signal identifier based on the logical operation.

In this case, the logical operation may be, for example, a logical concatenation of the respective logical one state and logical zero state of the semaphore. The logical connection may be, for example, an AND connection, an OR connection, a NOT AND connection, a NOR connection, an XOR connection, or an XOR connection. Alternatively, the logical operation may be another type of logical connection or logical operation rule that enables a determination of whether the received semaphore corresponds to a predetermined semaphore.

Based on the logical operation applied to the received signal identifier, the switching element 109 determines whether the received signal identifier coincides with a predetermined signal identifier, and switches the user 101 into a read state if the received signal identifier coincides with the predetermined signal identifier. If not, the switching element 109 keeps the user 101 in a sleep state and no data transfer occurs.

A coincidence is determined if the application of a logical operation to an accepted semaphore results in one or more logical true values that are the same as would be expected for the application of the logical operation to the predetermined semaphore.

After the end of the data transmission, the user 101 is also configured to autonomously return to the sleep state. By this, it is possible to ensure that: after the end of the data transfer, the user 101 does not remain in the read state, which may cause the user 101 to misinterpret a level change in the voltage applied to the data bus 105 as the issued data signal, which in turn may cause an erroneous data transfer.

In the embodiment of fig. 1, the data bus 105 is configured as a differential data bus with one twisted pair. Alternatively, the data bus 105 may also be configured as a differential data bus with two twisted pairs. Preferably, the data bus 105 can be designed as a serial interface, for example as a serial interface RS 485. For data transmission via the interface RS485, the UART protocol can additionally be used.

The UART protocol specifies: the data bus is set to a High Level (High Level) during the time when no data transfer is performed. To initiate a data transfer, each data packet of the data transfer is provided with a start bit which causes the data bus to fluctuate from a High Level (High Level) to a Low Level (Low Level). The user connected to the data bus interprets this level fluctuation as an initialization of the forthcoming data transmission and interprets the subsequent level fluctuation as a corresponding data signal. After the end of the data transmission, the respective sender of the data signal resets the data bus to a high level, thereby providing the data bus for the next data transmission.

As in the case of the system 100 in fig. 1, in the case of a system with a plurality of subscribers, in which a combined data transmission and energy transmission is implemented via a single data bus, the following problems arise: at least for the point in time when the transmitting user switches to the receiving state in order to receive a corresponding response signal of a further user, the data bus 105 is not driven for a relatively long time interval and therefore cannot remain at a High Level (High Level). During this time period, the voltage level on the data bus drops to zero.

If, in addition to the data transmission, energy supply is to be initiated via the data bus, the following problems additionally arise: since the filter units, which are required to protect the processor units of the subscribers against the application of the supply voltage, are connected between the data bus and these subscribers, it is not possible for the data bus to be kept at a High Level (High Level) by the sender continuously injecting current into the bus line.

According to the standard of the RS485 interface, voltage levels in the range between-200 mV and 200mV cannot be interpreted as a logic one state or a logic zero state for the receiving party. During a period in which the voltage drops from a High Level (High Level) to zero due to switching the transmitting side from the transmitting state to the receiving state, the receiving side is in an uncertain state in which the performance of the receiving side cannot be predicted. This uncertain state may lead to incorrect interpretation by the receiving party, which in turn may lead to erroneous data transmission by the respective user.

In the system 100 in fig. 1, such an uncertain state of the users 101, 103 of the system 100 can be avoided by means of the switching element 109 in the following way: during a time period in which a data transmission between the subscriber 101 and the further subscriber 103 is not imminent, the subscriber 101 or the further subscriber 103 is put into a sleep state in which the subscriber 101 or the further subscriber 103 does not read the voltage level applied on the data bus 105. In this way, the voltage level of the data bus, while continuing to be in an indeterminate range between-200 mV and 200mV, does not read the voltage level by the users 101, 103 in the sleep state, thereby avoiding misinterpretations by the users 101, 103 due to the indeterminate level.

To initiate a data transmission, the user 101 is switched by the switching element 109 into the read state by issuing a signal identifier in such a way that the user 101 reads the voltage level applied to the data bus 105, in particular the voltage level of the corresponding data signal. The data bus 105, in particular the serial interface RS485, does not have to be kept constantly at a High Level for the time in which no data transmission (Idle state of the data bus) is encountered. Furthermore, it is not critical for the data transmission that the voltage level of the data bus or serial interface RS485 is close to zero, in particular falling within an uncertainty range between-200 mV and 200 mV.

By configuring the subscribers 101, 103 of the system 100 with the switching element 109, it is also possible to avoid equipping the system 100 with a corresponding Fail-Safe (Fail-Safe) circuit. For operating an RS485 interface with a plurality of bus users, the problems described above are known: for the non-driven state (idle state of the bus), the voltage level on the bus falls within an indeterminate range between-200 mV and 200 mV. In general, the problem of indeterminate voltage states in the non-driven state of the bus is eliminated by the additional circuitry of the failsafe circuit, which is usually a combination of Pull-up (Pull-up) and Pull-down (Pull-down) resistors, which are each connected to a line of the RS485 interface and cause: the voltage level at the RS485 interface does not fall within an indeterminate range between-200 mV and 200mV in the non-driven state.

However, if the RS485 interface or the respective differential data bus would be used for combined data transmission and energy transmission as in the present case, it would be necessary to equip each subscriber with a respective fail-safe circuit, since these subscribers would have to be equipped with respective filter elements 113, 115 in order to protect the respective processor unit 111 of the respective subscriber 101, 103. The capacitance built into the filter element 113 causes: each user 101, 103 can be equipped with a corresponding fail-safe circuit.

As described above, by designing the subscribers 101, 103 each with a switching element 109, the corresponding fail-safe circuit can be dispensed with, since the voltage level of the data bus 105, in particular of the serial interface RS485, in the uncertainty range between 200mV and-200 mV is not critical for the data transmission within the system 100 by switching the subscribers 101, 103 into the sleep state by the switching element 109.

Fig. 2 shows a schematic illustration of a switching element 109 of a user 101 of a system 100 for combined data and energy transmission in an automation system 300, according to an embodiment.

According to fig. 2, the switching element 109 comprises a shift register 201, a logic element 205 and a holding element 207. The shift register 201 is connected to a logic element 205 and the logic element 205 is connected to a hold connection 207. The shift register 201 is configured such that: the signal identifier received through the transmission/reception unit 117 is registered. To this end, the shift register 201 includes a plurality of flip-flop elements 203 configured to temporarily store a logic one state or a logic zero state of the signal identifier, respectively.

In fig. 2, a shift register 201 is constructed with eight flip-flop elements 203. Alternatively, however, shift register 201 may also include four, sixteen, thirty-two, or any number of flip-flop elements 203. The number of flip-flop elements 203 of the shift register 201 limits the number of logic one states and logic zero states of the semaphore that can be considered in the decision by the switching element 109.

The logic element 205 is configured to: a logical operation is performed for determining whether the signal identifier received and registered by the shift register 201 coincides with a predetermined signal identifier.

The holding member 207 is configured to: based on the correspondence between the registered signal identifier and the predetermined signal identifier, as determined by the logic element 205, the user 101 is switched to the read state or is kept in the sleep state.

According to the embodiment shown in fig. 2, the logic element 205 is designed as a logic gate. The logic gate is in particular designed as a non-and gate (Nicht-UND-gate).

The logic gate comprises a first logic gate element 215, a second logic gate element 225, a third logic gate element 235 and a fourth logic gate element 245.

The second logic gate element 225 establishes a not-and connection between the logic one state or the logic zero state of the first flip-flop element 213 and the logic one state or the logic zero state of the third flip-flop element 233. The fourth logic gate element 245 establishes a non-AND connection between a logic one state or a logic zero state of the fifth flip-flop element 253 and a logic one state or a logic zero state of the seventh flip-flop element 273.

To this end, the second logic gate element 225 creates an and connection between the complement of the logic one state or logic zero state of the first flip-flop element 213 and the logic one state or logic zero state of the third flip-flop element 233. The complement corresponds in this case to a logical one state or a logical zero state which is the opposite of the logical one state or the logical zero state actually stored by the first flip-flop element 213.

Based on the AND connection, second logic gate element 225 creates a corresponding first logic true value.

The fourth logic gate element 245 creates an and connection between the complement of the logic one state or logic zero state of the fifth flip-flop element 253 and the logic one state or logic zero state of the seventh flip-flop element 273. Based on the AND connection, fourth logic gate element 245 determines a corresponding second logic true value.

First logic gate element 215 in turn creates an and connection between the two first and second logic true values created by second logic gate element 225 and fourth logic gate element 245. Based on the AND connection of the two logic true values, first logic gate element 215 determines a third logic true value and determines whether the registered semaphore matches the predetermined semaphore based on the third logic true value.

The registered signal designator corresponds to the predetermined signal designator if the same third logical true value is obtained for both signal designators. As described above, these logical true values are either logical one true values or logical zero true values.

An inconsistency is determined by logic element 205 if it determines a different logical true value for the registered semaphore than for the predetermined semaphore.

In the embodiment of fig. 2, the third logic gate element 235 is not used.

According to the embodiment shown in fig. 2, the holding element 207 comprises an S-R latch 209 and a multiplexer 211. The S-R latch 209 is connected via its S input S to a logic gate element 215. S-R latch 209 is connected to multiplexer 211 via output Q, S-R latch 211 with control input S0 of multiplexer 211. The multiplexer 211 is connected to the processor unit 111 of the subscriber 101 via the output O. The multiplexer 211 is connected to the data bus 105 of the system 100 via a first input E0. The second input E1 of the multiplexer 211 serves as a reference input and is set to a logic one state or a logic zero state. Preferably, the input E1 is set to a value that corresponds to the sleep Level, i.e. High Level (High Level), of the UART protocol downstream, i.e. to a logic one state.

Alternatively, a further circuit element (not shown in fig. 2) may be connected between the first input E0 of the multiplexer 211 and the data bus 105 in order to compensate for the delay of the logic element 205 and to avoid a lack of synchronization of the processor unit 111 due to this delay. For example, the first input E0 of the multiplexer 211 may be connected to an output of the shift register 201.

The S-R latch 209 is in turn connected to the processor unit 111 via the R input R.

S-R latch 209 receives a third logic true value from first logic gate element 215 via S input S. If the third logic true value corresponds to a coincidence of the registered semaphore with the predetermined semaphore, S-R latch 209 switches to a Set (Set) state. In the set state, S-R latch 209 transmits a corresponding switching signal through output Q to control input S0 of multiplexer 211. The multiplexer 211 then switches the first input E0 and the output O into the conducting position and thus connects the processor unit 111 with the data bus 105. Thus, the user 101 is in a read state and the data signal transmitted via the data bus 105 can be read by the processor unit 111.

According to fig. 1, a transmitting/receiving unit 117 is connected between the switching element 109 and the data bus 105. The transmitting/receiving unit is omitted in fig. 2 for simplicity of presentation.

If the third logic true value determined by first logic gate element 215 and forwarded to S-R latch 209 does not correspond to a match between the registered signal identifier and the predetermined signal identifier, S-R latch 209 does not switch to the set state and does not output a switch signal to control input S0 of multiplexer 211. Thus, the multiplexer 211 does not switch the first input E0 and the output O to a conductive state and no connection is established between the processor element 111 and the data bus 105. Thus, the user 101 is in a sleep state.

After the end of the data transfer, the processor unit 111 outputs a corresponding Reset (Reset) signal to the R input R of the S-R latch 209. The S-R latch 209 then switches to the reset state and sends a corresponding signal to the multiplexer 211 via the control input S0, the multiplexer 211 then breaking the connection between the processor unit 111 and the data bus 105. Thus, the user 101 is restored to the hibernation state.

The processor unit 111 connected to the output O of the multiplexer 211 and the processor unit 111 connected to the R input R of the S-R latch 209 in fig. 2 are respectively different functions of the same processor unit 111.

In the embodiment in fig. 2, the logic gate of the logic element 205 is configured as a non-and gate as described above, which takes into account only the logic one state or the logic zero state of the first flip-flop element 213, the third flip-flop element 233, the fifth flip-flop element 253 and the seventh flip-flop element 273. Alternatively, however, the logic gate may also be configured as another logic gate with other logic connections that take into account more or fewer logic one states or logic zero states of the flip-flop elements of the shift register 201.

The shift register 201 can be operated with a double clock rate of the symbol clock of the further subscriber 103, wherein the symbol clock corresponds to the clock used by the further subscriber 103 to issue symbols for communication during the data transmission. Alternatively, shift register 201 may operate with other data rates.

By operating shift register 201 with at least double the symbol clock of further subscriber 103 present as transmitter, it is possible to realize that: all logic one and zero states belonging to the issued semaphore are registered by the shift register 201. By correspondingly clocking the shift register 201 with double the symbol clock, it is avoided: since the further clocking of the logic one state and the logic zero state by the user 103 for signaling the identifier does not match the clocking of the shift register for registering the respective one state and the logic zero state of these logic one state and logic zero state, the respective one state or multi-stage zero state is not registered.

The design of the shift register 201, the logic gates of the logic element 205 and the wiring of the holding element 207, in particular the S-R latch 209 and the multiplexer 211, may also differ from the situation shown in fig. 2. The wiring between the shift register 201, the logic gates of the logic elements 205 and the holding elements 207 may likewise differ from the situation shown in fig. 2.

Fig. 3 shows a schematic illustration of an automation system 300 with a system 100 for combined data and energy transmission according to an embodiment. The automation system 300 comprises a control device 301, a second data bus 307, a voltage supply device 107 and two bus couplers 303 connected to the second data bus 307. The automation system 300 also comprises two systems 100 for combined data and energy transmission, each comprising a user 101 and three further users 103, each of which is connected via a data bus 105. The two systems 100 are integrated into an automation system 300 via a bus coupler 303. Each of the data buses 105 further comprises a termination 305, which is formed at the end of the data bus 105 and serves to prevent reflections of the emitted data signals at the end of the data bus 105. The users 101, 103 of the system 100 are supplied with a supply voltage via a data bus 105 by means of a voltage supply 107.

In the embodiment shown in fig. 3, one of the further users 103 is connected to a bus coupler 303 of the automation system 300. In the system 100, the further subscriber 103 assumes the function of a bus master, while the two further subscribers 103 and the subscriber 101 assume the function of a bus slave.

The respective system 100 and the respective data bus 105 are coupled to a second data bus 307 of the automation system 300 by means of a bus coupler 303. The second data bus 307 can be designed, for example, as a field bus. The second data bus 307 may also be based on an industrial ethernet protocol, such as the EtherCAT protocol. By means of the bus coupler 303, the two communication protocols of the data bus 105 and the second data bus 307 can be coupled to one another, so that a communication of the control device 301 of the automation system 300 with one of the users 101, 103 of the two systems 100 can be achieved. In the embodiment in fig. 3, user 101 and further user 103, which assume the function of a bus slave, may each comprise a sensor, an actuator or another device of automation system 300. By means of the further user 103 acting as a bus master, the mentioned users 101, 103 can be manipulated according to the operating rules of the control device 301 of the automation system 300 to carry out corresponding operations, to record measured values or to output further status reports, and to communicate with the control device 301 via the data bus 105 and the second data bus 307.

Fig. 4 shows another schematic diagram of a system 100 for combined data and energy transmission in an automation system 300 according to an embodiment.

In fig. 4, only a user 101 and a further user 103 of the system 100 are shown, the user 101 and the further user 103 being connected to one another by a data bus 105. The supply voltage of the voltage supply 107 is supplied to the user 101 and the further user 103 via the data bus 105.

The data bus 105 is in turn constructed as a differential data bus with two twisted pair lines. The data bus 105 also has two terminals 305, which are formed at both ends of the data bus 105. Each of these terminals 305 has a first capacitance 401 and a first inductance 403. These terminals 305 are configured to suppress reflections of data signals emitted through the data bus 105. The terminals 305 are designed such that the resistance of the terminals 305 corresponds to the wave resistance of the lines of the data bus 105.

The user 101 and the further user 103 each have a second filtering unit 115. The second filtering unit 115 includes a second capacitor 405, a third capacitor 407, a second inductor 409, and a third inductor 411, respectively. In the embodiment of fig. 4, the second filtering unit 115 is configured to include a pass filter, preferably a high pass filter. Thereby, the second filtering unit 115 is only able to pass voltage signals having frequencies from the selected frequency range. Preferably, the selected frequency range of the second filter unit 115 corresponds to the frequency range of data signals which are emitted by the subscriber 101 or by the further subscriber 103 via the data bus 105 for data transmission. Thus avoiding: the voltage level of the supply voltage is applied to the processor unit 111 of the user 101 or the further user 103 and damages this user or this further user.

In fig. 4, the user 101 and the further user 103 comprise all features of the user shown in fig. 1. The presentation of the switching element 109, the processor unit 111, the second filtering unit 115 and the transmission/reception unit 117 has been omitted in fig. 4 for clarity only. Also, for reasons of clarity, only the user 101 and the further user 103 are shown in fig. 4. However, the system 100 should not be limited to the number of users shown in FIG. 4 nor the number of users shown in FIG. 1. Rather, the system 100 may include any number of users 101, 103.

Fig. 5 shows a schematic illustration of a user 101 of an automation system 300 with a system 100 for combined data and energy transmission in an automation system according to an embodiment.

According to fig. 5, the user 101 comprises a processor unit 111 for reading data signals of further users 103 of the system 100 for combined data transmission and energy transmission in the automation system 300. The user 101 further comprises a switching element 109 for switching the user 101 from the sleep state into the read state. The user 101 further comprises a transmitting/receiving unit 117 for transmitting and receiving data signals for data transmission between the user 101 and at least one further user 103 of the system 100. The user 101 further comprises a filtering unit 113 and a second filtering unit 115. The filter unit 113 can be designed, for example, as a low-pass filter and is used to ensure the voltage supply to the user 101 with the supply voltage applied to the data bus 105. For this purpose, the filter unit 113 can be designed with a coupling element 501 for galvanic coupling of the subscriber 101 to the supply voltage.

The second filtering unit 115 may include a high pass filter and is configured to: the data signal is separated from the supply voltage applied on the data bus 105 so that only the voltage level of the data signal is applied on the processor unit 111.

The processor unit 111 is connected to the switching element 109. The switching element 109 is connected to the transmission/reception unit 117. The transmitting/receiving unit 117 is connected to the filtering unit 113 and to the second filtering unit 115.

The signal identifier transmitted via the data bus 105 is forwarded to the transmitting/receiving unit 17 via the second filter unit 115 and received by the latter. The switching element 109 connected to the transmitting/receiving unit 117 determines whether the received signal identifiers coincide according to the steps described with respect to fig. 1 and 2.

In the case of a coincidence of this signal identifier with a predetermined signal identifier, the switching element 109 switches the user 101 into the reading state, whereby a connection between the processor unit 111 and the data bus 105 is established via the second filter unit 115 and the transmission/reception unit 117. Thus, a data transmission between the user 101 and at least one further user 103 of the system 100 can be achieved.

The user 101 may also include sensors, actuators, or other devices of the automation system 300, which are not shown in fig. 5.

Fig. 6 shows a flowchart of a method 600 for combined data and energy transmission in automation system 300, according to an embodiment.

As indicated above, the automation system 300 comprises a user 101 and at least one further user 103, which are connected to one another by a data bus 105 and are configured to communicate with one another by exchanging data signals via the data bus 105. The automation system 300 also comprises a voltage supply 107 for supplying a supply voltage to at least the user 101 and, if appropriate, the further user 103 via the data bus 105. At least the user 101 comprises a switching element 109 for switching the user 101 from the sleep state into the read state.

In fig. 6, the operation performed by the further user 103 acting as a sender of the data signal is shown separately from the operation performed by the user 101 acting as a receiver of the data signal sent by the further user 103. The solid arrows shown in fig. 6 represent the temporal and causal sequence of the operations carried out by the user 101 and by the further user 103. Whereas the dashed arrows symbolically represent the logical connection of the two operating branches of the user 101 and the further user 103.

According to fig. 6, the method 600 comprises: in an identifier sending step 601, a signal identifier is sent by the further user 103 to the user 101 via the data bus 105 for initializing the data transfer; in an identifier accepting step 603, the signal identifier is accepted by the switching element 109 of the user 101; in a checking step 605, it is checked by the switching element 109 whether the received signal identifier corresponds to a predetermined signal identifier; if the received signal identifier corresponds to the predetermined signal identifier, the user 101 is switched to the read state by the switching element 109 in a switching step 607; in a data transmission step 609, the data packets are transmitted by the further subscriber 103 to the subscriber 101 for data transmission; in a reading step 611, the data packets issued by the further user 103 are read by the user 101; after the data transmission is ended, the subscriber 101 is restored to the sleep state by the subscriber 101 in a restoration step 613; or if the accepted signal identifier does not correspond to the predetermined signal identifier, the user 101 is kept in a sleep state by the switching element 109 in a holding step 615.

In order to initialize an upcoming data transmission between two users 101, 103 of the system 100, the further user 103, which in the present description assumes the sender function, sends a signal identifier to the user 101, which in the following assumes the receiver function, in an identifier sending step 601. At the point in time when the signal identifier is transmitted by the further subscriber 103, the subscriber 101 is in a sleep state and is therefore not able to read the data signal and participate in the data transmission.

The user 101, and also the further user 103, are designed as described in relation to fig. 1 to 5 and comprise a filtering unit 113, a second filtering unit 115, a transmitting/receiving unit 117, a switching element 109 and a processor unit 111. The user 101 separates the emitted signal identifier from the supply voltage applied to the data bus 105 by means of the second filter unit 115.

After the transmission of the signal identifier by the further user 103 in an identifier transmission step 601, the user 101 receives the emitted signal identifier via the transmission/reception unit 117 and forwards the signal identifier to the switching element 109, so that the emitted signal identifier is accepted by the switching element 109 of the user 101 in an identifier acceptance step 603.

In a checking step 605, the switching element 109 checks the signal identifier in order to determine whether the signal identifier corresponds to a predetermined signal identifier.

If the switching element 109 determines that the accepted signal identifier corresponds to the predetermined signal identifier, the switching element 109 switches the user 101 into the reading state in a switching step 607.

After the signaling of the identifier in time, at least one further subscriber 103 of the system 100 transmits the data packet to the subscriber 101 in a data transmission step 609 for data transmission. Alternatively, the further subscriber 103 may also send a plurality of data packets for data transmission. The user 101 remains in the read state until the end of the data transfer between the user 101 and the further user 103. No other signal identifier has to be transmitted.

The issued data packet or packets pass through the second filtering unit 115 and are received by the transmitting/receiving unit 117. Since the switching element 109 has switched the user 101 into the reading state, the connection between the transmitting/receiving unit 117 and the processor unit 111 is switched into the conductive state. The data packet received by the transmission/reception unit 117 is read by the processor unit 111 of the user 101 in a reading step 611.

After the end of the data transfer between the subscriber 101 and the further subscriber 103, the subscriber 101 reverts to the dormant state in a reversion step 613. Consequently, a subsequent data transmission between the user 101 and the further user 103 is temporarily no longer possible.

If the switching element 109 determines in a checking step 605 that a correspondence between the received signal identifier and the predetermined signal identifier does not exist, the switching element maintains the subscriber 101 in a sleep state in a maintaining step 615. Thus, no data transmission between the user 101 and the further user 103 takes place. Subscriber 101 remains in a dormant state until the subscriber receives a valid signal identifier.

If the further user 103 or other further users 103 send another signal identifier, the method 600 starts again with an identifier sending step 601. Characterized by the arrow pointing back from the hold step 615 to the identifier acceptance step 603: in the holding step 615, in the event that a further user 103 re-emits the signal identifier SK, the user 101 can accept the signal identifier SK in an identifier acceptance step 603 and check the signal identifier SK in a checking step 605. Thus, the method 600 may be performed continuously and continually by continuously transmitting signal identifiers to a user 101 or a plurality of users 101 and receiving these signal identifiers by said user 101 or said plurality of users 101. In case the signal identifier is valid, the respective user 101 switches to a receiving state. If the signal identifiers received by subscribers 101 are invalid, i.e. do not correspond to the signal identifiers predetermined for the respective subscriber 101, then these subscribers 101 remain in the sleep state and do not switch into the receiving state.

The method 600 may also be performed simultaneously between different users 101, 103 by signaling an identifier by the different users 101, 103.

The energy transmission via the data bus 105 in the form of the supply voltage of the voltage supply 107 takes place continuously during all the above-mentioned method steps of the method 600.

Fig. 7 shows a flow diagram of a method 600 for combined data and energy transmission in automation system 300, according to a further embodiment.

The method 600 of fig. 7 corresponds to the method 600 of fig. 6 and includes the same method steps, as long as they are not described otherwise.

As in fig. 6, in fig. 7, the operation performed by the further user 103 acting as the sender of the data signal is shown separately from the operation performed by the user 101 acting as the receiver of the data signal sent by the further user 103. The solid arrows shown in fig. 7 represent the temporal and causal sequence of the operations carried out by the user 101 and by the further user 103. Whereas the dashed arrows symbolically represent the logical connection of the two operating branches of the user 101 and the further user 103.

According to the embodiment in fig. 7, the checking step 605 comprises a logical operation step 701. In a logic operation step 701, the switching element 109 performs a logic operation. The checking step 605 further comprises a comparing step 703 in which the switching element 109 compares the received signal identifier with a predetermined signal identifier based on the logical operation. Additionally, the checking step 605 comprises a determining step 705 in which the switching element determines whether the received signal identifier and the predetermined signal identifier coincide based on the comparing step 703.

If the two signal identifiers are consistent, the method 600 continues with the switching step 607 and the steps described next with respect to FIG. 6. If the two signal identifiers do not coincide, the method continues with a hold step 615.

As already described above, a coincidence exists if applying a logical operation to the signal indicator yields a logical true value or logical true values corresponding to a logical true value or logical true values that would be expected or obtained when the logical operation is applied to a predetermined signal indicator.

To this end, according to one embodiment, the switching element 109 may include a shift register 201, a logic element 205, and a holding element 207. The logic element 205 is configured to: performing a logical operation in a logical operation step 701; in a comparing step 703, the received signal identifier is compared with a predetermined signal identifier based on the logical operation; and determines in a determination step 705 whether the received signal identifier corresponds to a predetermined signal identifier.

The holding member 207 is configured to: in a holding step 615, the user 101 is kept in a sleep state. The holding member 207 is further configured to: in a switching step 607, the user 101 is switched to a read state.

According to one embodiment, the shift register 201, logic element 205, and holding element 207 may be constructed like in FIG. 2. In this case, the execution of the logical operation may be performed by a logic gate similar to that described with respect to fig. 2.

The signal identifier received by the transmission/reception unit 117 is registered by the shift register 201. To this end, each of the flip-flop elements 203 of the shift register 201 accepts a logic one state or a logic zero state of the signal identifier, respectively, and temporarily stores the logic one state or the logic zero state. In order to register the signal identifier by means of the shift register 201, the shift register is operated with at least double the symbol clock of the transmitting further subscriber 103.

After the received signal identifier is registered by the shift register 201, the logic gate of the logic element 205 performs a logical connection corresponding to the logic gate of the registered signal identifier, either the logic one state or the logic zero state stored in the flip-flop element 203.

As shown in fig. 2, the logic gate may be a non-and association in which an and logic connection of the inverted value of the logic one state or logic zero device of one of the flip-flop elements 203 with the logic one state or logic zero state of the other flip-flop element 203 is performed in pairs, respectively. Based on these not-and connections performed by the logic gate, a logical true value corresponding to the connection is created. The signal designators that result in the same true value in the process are determined to be consistent.

The logic gate of the logic element 205 forwards a signal corresponding to the coincidence of the registered signal identifier and the predetermined signal identifier to the holding element 207, which then switches the user 101 into the read state. As described with respect to fig. 2, two signposts are identical if applying a logical operation to the corresponding signpost results in the same logical true value for the logical operation.

In the event of coincidence and the corresponding signal being issued by the logic element 205 to the holding element 207, the S-R latch 209 and the multiplexer 211 of the holding element 207 switch the connection of the data bus 105 to the processor unit 111 to the conductive position, so that the user 101 is in a read state and the data signal transmitted via the data bus 105 can be read by the processor unit 111.

As explained under fig. 2, the shift register 201, the logic element 205 and the holding element 207 are not limited to the embodiment shown in fig. 2. Alternatively, not only the shift register 201 but also the logic element 205 and the holding element 207 may be designed differently.

Fig. 8a shows a voltage-time diagram of a data packet DP without a signal identifier SK according to the prior art signaling standard.

In fig. 8a, a voltage waveform with a plurality of data signals DS on the data bus is shown. In fig. 8a, 8b and throughout the disclosure, the data signal DS is to be understood as a voltage level which corresponds to a logic one state or a logic zero state according to the signaling protocol.

In fig. 8a, a plurality of data signals DS are combined into one data packet DP. The data packet DP is constructed according to the UART protocol. The UART protocol specifies a data packet DP which comprises a start bit SB1 and an end bit SB 2. The start bit SB1 and the end bit SB2 are the start point and the end point of the packet DP. The data packet DP further comprises eight data bits DB, which may be in a logic one state or a logic zero state, respectively, and which comprise the actual data of the data packet DP. The start bit SB1 is a logic zero state and the end bit SB2 is a logic one state, and the start bit and the end bit are used merely to characterize the start and end of the data packet DP, but otherwise do not contribute to the data transmission.

In fig. 8a, a logic one state is illustrated by the high level HL of the voltage U. The logic zero state is presented by a low level LL of the voltage U.

The UART protocol also specifies: during the time periods in which no data transmission takes place by means of the data packet DP, a voltage U with a high level HL is applied to the data bus. The continuous high level HL signals an idle state of the data bus in which the data bus is not driven by a user.

The start bit SB1 of the data packet DP, which is used to initialize the data transmission, signals the receiving party by a level change of the start bit SB1 from a high level HL to a low level LL in a period in which no data transmission is performed: data transmission is forthcoming.

To end the data transmission, the end bit SB2 is connected to the end of the last data packet DP and has a high level HL, by means of which the data bus is reset to the idle state and the receiver is signaled: the data transmission is ended.

In fig. 8a, a low level LL is arranged at a voltage value of 0, while a high level HL is arranged at an arbitrary positive voltage value. The signal coding shown in fig. 8a therefore has a direct current component.

A high level HL in the time periods in which no data transmission takes place can also be realized by a failsafe circuit which causes: for the case, for example, in which the UART protocol is run on the serial interface RS485, the voltage level on the data bus does not fall within an indeterminate range between 200mV and-200 mV in the idle state.

Fig. 8b shows a voltage-time diagram of a data packet DP with a signal identifier SK according to an embodiment.

The data packet DP is again formed according to the UART protocol and comprises a start bit SB1, an end bit SB2 and eight data bits DB.

Unlike the data packet in fig. 8a, in fig. 8b a signal identifier SK is added to the front of the data packet DP. In fig. 8b, the signal identifier SK is shown as an alternating sequence of logic one states and logic zero states. In the embodiment of fig. 8b, the logic one and zero states of the signal identifier SK are emitted at a higher frequency than the individual bits of the data packet DP. However, the logic one state and the logic zero state of the signal identifier SK may not be emitted at the same frequency of the bits of the data packet DP or at a lower frequency of the bits of the data packet DP.

Unlike the data packet DP in fig. 8a, in fig. 8b the voltage level is not adjusted to the high level HL during the time period in which no data transmission is taking place, but has the value zero. In fig. 8b, for the purpose of initializing the communication between the sender and the receiver, the start bit SB1 of the data packet DP is not used, but the signal identifier SK preceding the data packet DP in time is used. The subscriber 101 is switched into the receiving state by means of the signal identifier SK, so that the subscriber is only then able to transmit data. Then, as in fig. 8a, the actual data transmission starts with a start bit SB1, so that the UART protocol is complied with for the actual data transmission.

As already described above, the switching element 109 reads the signal identifier SK preceding the data packet DP and switches the user 101 into the read state if the registered signal identifier SK corresponds to a predetermined signal identifier. In this case, the user 101 reads the data packet DP following the signal identifier SK by means of the processor unit 111. In this case, the start bit SB1 signals the beginning of the data packet DP and the actual data transmission to the subscriber 101. After the end of the data transmission, as indicated, for example, by the end bit SB2 of the data packet DP, the subscriber 101 switches back to the sleep state in which the signals applied to the data bus are not read. Thus, it is possible to omit: in the idle state, the data bus is kept at a high level HL.

The start of the data transmission is no longer signaled by a level change of the start bit from the high level HL to the low level LL in the idle state, but by the registered signal identifier SK. Because the signals of the data bus are not read by the subscribers 101, 103 in the sleep state, the data bus does not have to be held at a specific voltage level, for example a voltage level outside the range between-200 mV and 200 mV.

The digital signal DS of the data packet DP and the signal identifier SK may be encoded in a signal encoding without a dc component (not shown in fig. 8 b). For example, Manchester (Manchester) coding or 6b8b coding can be used for this purpose. Alternatively, any other encoding without a dc component may be used.

List of reference numerals

100 System for combined data and energy Transmission in an Automation System

101 user

103 further users

105 data bus

107 voltage supply device

109 switching element

111 processor unit

113 filter unit

115 second filter unit

117 transmitting/receiving unit

201 shift register

203 trigger element

205 logic element

207 holding element

209S-R latch

S S-R latch S input terminal

R S-R latch R input terminal

Q S-R latch output

211 multiplexer

First input terminal of E0 multiplexer

Second input terminal of E1 multiplexer

Control input of S0 multiplexer

Output terminal of O multiplexer

213 first flip-flop element

223 second trigger element

233 third trigger element

243 fourth trigger element

253 fifth flip-flop element

263 sixth flip-flop element

273 seventh trigger element

283 eighth flip-flop element

215 first logic gate element

225 second logic gate element

235 third logic gate element

245 fourth logic gate element

300 automated system

301 control device

303 bus coupler

305 terminal

307 second data bus

401 first capacitance

403 first inductance

405 second capacitance

407 third capacitance

409 second inductor

411 third inductor

501 coupling element

600 method for combined data and energy transmission in an automation system

601 identifier sending step

603 identifier accepting step

605 inspection step

607 switching step

609 data transmission step

611 read step

613 returns to the step

615 holding step

701 logical operation step

703 comparing step

705 determining step

SK signal identifier

DS data signal

DP data packet

SB1 Start bit

SB2 end bit

DB data bit

U voltage

time t

HL High Level (High Level)

LL Low Level (Low Level)

Claims (19)

1. A system (100) for combined data transmission and energy transmission in an automation system (300), comprising:

-a user (101) and at least one further user (103) of an automation system (300), which are connected to each other by a data bus (105) and are configured to communicate with each other by exchange of Data Signals (DS) via the data bus (105), wherein the user is a participant of a data communication via the data bus (105); and

-voltage supply means (107) for supplying at least said user (101) with a supply voltage via said data bus (105);

-wherein at least the user (101) comprises a switching element (117) for switching the user (101) from a sleep state, in which the user (101) does not read the Data Signal (DS) issued by the further user (103), to a read state, in which the user (101) reads the Data Signal (DS) issued by the further user (103);

-wherein the switching element (117) comprises:

-a shift register (201) for registering a signal identifier (SK) of the further subscriber (103); and

-a logic element (205) connected to the shift register (201) for determining whether the registered signal identifier (SK) corresponds to a predetermined signal identifier, wherein the logic element (205) is configured as a logic gate having a plurality of logic gate elements, wherein the logic gate elements are configured to establish a logical connection between entries of the shift register (201), and wherein the logic gate is configured to: determining at least one logical true value based on a logical connection of entries of the shift register (201) and determining, based on the at least one logical true value: whether a signal identifier (SK) emitted by the further user (103) for initializing a data transmission corresponds to a predetermined signal identifier, and wherein the switching element (117) is designed to: switching the user (101) into a read state if the received signal identifier (SK) corresponds to a predetermined signal identifier; or if the received signal identifier (SK) does not correspond to a predetermined signal identifier, keeping the user (101) in a sleeping state; and

-wherein the user (101) is configured to be able to resume from the read state to the hibernate state.

2. The system (100) according to claim 1, wherein the switching element (117) is configured to: -performing a logical operation, and-based on the logical operation-comparing the received signal identifier (SK) with a predetermined signal identifier and determining whether the received signal identifier (SK) and the predetermined signal identifier coincide.

3. The system (100) according to claim 1, wherein the switching element (117) comprises:

-a holding element (207) connected to the logic element (205) for switching the user (101) into a read state if the logic element (205) determines that the accepted signal identifier (SK) corresponds to a predetermined signal identifier, and for holding the user (101) in a sleep state if the logic element (205) determines that the signal identifier (SK) does not correspond to a predetermined signal identifier.

4. The system (100) of claim 3, wherein the holding element (207) comprises an S-R latch (209) and a multiplexer (211).

5. The system (100) of any of the above claims, wherein the data bus (105) is a differential data bus.

6. System (100) according to any of claims 1 to 4, wherein the Data Signals (DS) emitted by the users (101) and/or by the further users (103) are encoded in a signal encoding without a DC component.

7. System (100) according to any one of claims 1 to 4, wherein the user (101) and/or the further user (101) are coupled to the data bus (105) by means of a coupling element (501) in order to take the supply voltage.

8. The system (100) according to any one of claims 1 to 4, further comprising:

-at least one filtering element (113) for separating at least one user's Data Signal (DS) from the supply voltage, wherein the filtering element comprises a high-pass filter and/or a low-pass filter.

9. User (101) for a system (100) according to one of the preceding claims 1 to 8, wherein the user (101) is configured to communicate with at least one further user (103) of an automation system (300) by exchange of Data Signals (DS) via a data bus (105) of the automation system (300) and to be supplied with a supply voltage by a voltage supply (107) of the automation system (300) via the data bus (105), wherein the user is a participant in data communication via the data bus (105), the user comprising:

-a processor unit (111) for reading Data Signals (DS) of a further user (103) of the automation system (300);

-a coupling element (501) for coupling the user (101) to the data bus (105) to receive the supply voltage; and

-a switching element (109) for switching the user (101) into a reading state in which the processor unit (111) is able to read the received Data Signal (DS) and for keeping the user (101) in a sleep state in which the processor unit (111) does not read the received Data Signal (DS),

wherein the switching element (109) comprises:

-a shift register (201) for registering a signal identifier (SK) of the further subscriber (103); and

-a logic element (205) connected to the shift register (201) for determining whether the registered signal identifier (SK) corresponds to a predetermined signal identifier, wherein the logic element (205) is configured as a logic gate having a plurality of logic gate elements, wherein the logic gate elements are configured to establish a logical connection between entries of the shift register (201), and wherein the logic gate is configured to: determining at least one logical true value based on the logical connection of entries of the shift register (201) and determining, based on the at least one logical true value: whether a signal identifier (SK) emitted by the further user (103) for initializing a data transmission corresponds to a predetermined signal identifier, and wherein the switching element (117) is designed to: switching the user (101) into a read state if the received signal identifier (SK) corresponds to a predetermined signal identifier; and if the received signal identifier (SK) does not correspond to a predetermined signal identifier, keeping the user (101) in a sleeping state; and

-wherein the user (101) is configured to revert to a dormant state.

10. The user (101) according to claim 9, wherein the switching element (109) is configured to: performing a logical operation and based on the logical operation comparing the received signal identifier (SK) with a predetermined signal identifier and determining whether the received signal identifier (SK) coincides with the predetermined signal identifier.

11. The user (101) according to claim 9, wherein the switching element (109) comprises:

-a holding element (207) connected to the logic element (205) for switching the user (101) into a read state if the registered signal identifier (SK) corresponds to a predetermined signal identifier, and for holding the user (101) in a sleep state if the registered signal identifier (SK) does not correspond to a predetermined signal identifier.

12. The user (101) of claim 9, wherein the holding element (207) comprises an S-R latch (209) and a multiplexer (211).

13. The user (101) of claim 9, wherein the coupling element (501) is a galvanic coupling element enabling galvanic coupling of the user (101) with a supply voltage provided on the data bus (105).

14. The user (101) as claimed in claim 9, further comprising at least one filtering element (113) for separating a Data Signal (DS) from the supply voltage, wherein the filtering element (113) comprises a high-pass filter and/or a low-pass filter.

15. The user (101) of claim 9, further comprising at least a sensor or actuator for an automated system (300).

16. A method (600) for combined data transmission and energy transmission in an automation system (300), wherein the automation system (300) comprises: a user (101) and at least one further user (103) which are connected to each other by a data bus (105) and are configured to communicate with each other by an exchange of Data Signals (DS) via the data bus (105), wherein the user is a participant in a data communication via the data bus (105); and a voltage supply device (107) for supplying a supply voltage to at least the subscribers (101) via the data bus (105), wherein at least the subscribers (101) comprise a switching element (109) for switching the subscribers (101) from a sleep state, in which the subscribers (101) do not read the Data Signals (DS) issued by the further subscribers (103), to a read state, in which the subscribers (101) read the Data Signals (DS) issued by the further subscribers (103), wherein the switching element (109) comprises a shift register (201) and a logic element (205) connected to the shift register (109), wherein the logic element (205) is configured as a logic gate with a plurality of logic gate elements, and wherein the method (600) comprises:

-in an identifier sending step (601), a signal identifier (SK) is sent by the further user (103) to the user (101) over the data bus (105) for initializing a data transmission;

-registering the signal identifier (SK) by a shift register (201) of a switching element (109) of the user (101) in an identifier accepting step (603);

-checking, in a checking step (605), by the switching element (109), whether the accepted signal identifier (SK) coincides with a predetermined signal identifier, wherein the checking step (605) further comprises:

-in a logical operation step (701), creating logical connections between entries of said shift register (201) through logical gate elements of said logical gates;

-in a comparison step (703), determining, by said logic gate, at least one logical true value based on the logical connection of entries of said shift register (201); and

-in a determining step (705), determining, by the switching element (109), based on the at least one logical true value, whether the received signal identifier (SK) coincides with a predetermined signal identifier;

-switching the user (101) into a reading state by the switching element (109) in a switching step (607) if the accepted signal identifier (SK) corresponds to a predetermined signal identifier;

-sending, by the further user (103), a Data Packet (DP) to the user (101) for the data transmission in a data sending step (609);

-reading, by the user (101), in a reading step (611), a Data Packet (DP) issued by the further user (103);

-after ending said data transmission, restoring said user (101) to a sleep state by said user (101) in a restoring step (613); or

-if the accepted signal identifier (SK) does not correspond to a predetermined signal identifier, keeping the user (101) in a sleep state by the switching element (109) in a keeping step (615).

17. The method (600) of claim 16, wherein the switching element (109) comprises a holding element (207), wherein in the holding step (615) the holding element (205) holds the user (101) in a sleep state.

18. The method (600) of any of the preceding claims 16, 17, wherein the Data Signals (DS) issued by the users (101) and/or by the further users (103) are encoded in a signal encoding without a direct current component.

19. The method (600) as claimed in any of claims 16, 17, wherein the voltage supply device (107) loads the data bus (105) with a supply voltage for the user (101) and/or the further user (103), and wherein the user (101) and/or the further user (103) extracts the supply voltage by means of a coupling element (501).

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