CN115102657A - Clock frequency synchronization method and device of metering device and storage medium - Google Patents

Abstract

The invention discloses a clock frequency synchronization method, device and storage medium of a metering device. The method for synchronizing the clock frequency of the metering device is applied between various metering devices of the metering device at the level of the station area, including: detecting the network status of the metering device, and determining the network state of the metering device, wherein the network state includes an online state and an offline state. ; Determine the frequency control mode of the metering device according to the network status, wherein the frequency control mode is realized by a preset frequency control module; Frequency control module; according to time delay, time offset and control mode, the clock frequency synchronization of each metering device of the metering device is performed. The technical problem in the prior art that a large number of metering devices at the station level lacks effective time synchronization means and cannot meet the needs of the smart grid is solved.

Description

A clock frequency synchronization method, device and storage medium of a metering device

technical field

The present invention relates to the technical field of electric power measurement, and in particular, to a clock frequency synchronization method, device and storage medium of a metering device.

Background technique

With the development of power grid informatization and digitization, a large number of devices are connected, and the topology of the distribution network is becoming more and more complex. The nodes serving different functions in the entire distribution network also correspond to the level requirements of different time synchronization accuracy. For example, the time synchronization accuracy required for power management, load monitoring and power acquisition is 1 second; the time synchronization accuracy for SCADA monitoring is 10ms; the time sequence recording (SOE) time synchronization accuracy is 1ms; and the synchrophasor measurement (PMU) ) with a time synchronization accuracy of 1 μs.

At present, the large number of metering devices of the State Grid at the Taiwan-area level lack effective time synchronization means and cannot meet the needs of smart grids. Therefore, the research on the economical and reliable time-frequency value transfer and time synchronization system in the intelligent distribution network plays a key role in effectively solving a series of problems introduced by the intelligent distribution network.

In view of the above-mentioned technical problems in the prior art that a large number of metering devices at the station level lack effective time synchronization means and cannot meet the needs of the smart grid, no effective solution has been proposed yet.

Embodiments of the present disclosure provide a clock frequency synchronization method, device, and storage medium for a metering device, so as to at least solve the problem that existing in the prior art, a large number of metering devices at the station level lack effective time synchronization means and cannot meet the needs of smart grids. technical issues of demand.

According to an aspect of the embodiments of the present disclosure, a method for synchronizing a clock frequency of a metering device is provided, which is applied between various metering devices of the metering device at the station level, including:

Detect the network status of the metering device, and determine the network status of the metering device, wherein the network status includes an online state and an offline state;

Determine the frequency control mode of the metering device according to the network state, wherein the frequency control mode is realized by a preset frequency control module;

Calculate the time delay and time offset between each metering device of the metering device, wherein each metering device is respectively provided with a frequency control module;

According to the time delay, time offset and control method, the clock frequency of each metering device of the metering device is synchronized.

According to another aspect of the embodiments of the present disclosure, a storage medium is further provided, and the storage medium includes a stored program, wherein when the program runs, any one of the methods described above is executed by a processor.

According to another aspect of the embodiments of the present disclosure, a clock frequency synchronization device for a metering device is also provided, which is applied between various metering devices of the metering device at the station area level, including:

a first determining module, configured to detect the network status of the metering device, and determine the network status of the metering device, wherein the network status includes an online status and an offline status;

The second determining module is used for determining the frequency control mode of the metering device according to the network state, wherein the frequency control mode is realized by a preset frequency control module;

a calculation module, used for calculating the time delay and time offset between various measurement devices of the measurement device, wherein each measurement device is respectively provided with a frequency control module;

The synchronization module is used for synchronizing the clock frequency of each metering device of the metering device according to the time delay, time offset and control mode.

According to another aspect of the embodiments of the present disclosure, a clock frequency synchronization device for a metering device is also provided, which is applied between various metering devices of the metering device at the station area level, including:

processor; and

a memory, connected to the processor, for providing instructions for the processor to perform the following processing steps:

Detect the network status of the metering device, and determine the network status of the metering device, wherein the network status includes an online state and an offline state;

Determine the frequency control mode of the metering device according to the network state, wherein the frequency control mode is realized by a preset frequency control module;

Calculate the time delay and time offset between each metering device of the metering device, wherein each metering device is respectively provided with a frequency control module;

According to the time delay, time offset and control method, the clock frequency of each metering device of the metering device is synchronized.

In the embodiment of the present disclosure, by setting different frequency control strategies for different network states, the problem of traceability of the local frequency source of the metering device is solved, and the frequency accuracy of the metering device in online condition and short-term frequency accuracy in offline condition is ensured. And by calculating the time delay and time offset measurement method between the various metering devices of the metering device, the problem of traceability of absolute time is realized, and the performance requirements for time synchronization in power informatization are met. To achieve the technical effect of accurate time synchronization between the metering devices of the metering device at the platform level. This further solves the technical problem in the prior art that a large number of metering devices at the station level lack effective time synchronization means and cannot meet the needs of the smart grid.

Description of drawings

The accompanying drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of the present disclosure. The exemplary embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation of the present disclosure. In the attached image:

1 is a block diagram of a hardware structure of a computing device for implementing the method according to Embodiment 1 of the present disclosure;

2A is a schematic diagram of a system for transmitting power time code magnitude using power carrier communication according to Embodiment 1 of the present disclosure;

2B is a schematic diagram of establishing a time topology relationship between terminal nodes based on a power carrier network according to the first aspect of Embodiment 1 of the present disclosure;

3 is a schematic flowchart of a method for synchronizing a clock frequency of a metering device according to the first aspect of Embodiment 1 of the present disclosure;

4 is a schematic diagram of the frequency control module according to the first aspect of Embodiment 1 of the present disclosure;

5 is a schematic diagram of a process of evaluating the magnitude transfer of a clock frequency according to the first aspect of Embodiment 1 of the present disclosure;

6 is a schematic diagram of a time delay and time offset measurement process according to the first aspect of Embodiment 1 of the present disclosure;

7 is a schematic diagram of a clock frequency synchronization device of a metering device according to Embodiment 2 of the present disclosure;

FIG. 8 is a schematic diagram of a clock frequency synchronization device of a metering device according to Embodiment 3 of the present disclosure.

Detailed ways

In order to make those skilled in the art better understand the technical solutions of the present disclosure, the following will clearly and completely describe the technical solutions in the embodiments of the present disclosure with reference to the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only some, but not all, embodiments of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present disclosure.

It should be noted that the terms "first", "second" and the like in the description and claims of the present disclosure and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific sequence or sequence. It is to be understood that the data so used may be interchanged under appropriate circumstances such that the embodiments of the disclosure described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having" and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those expressly listed Rather, those steps or units may include other steps or units not expressly listed or inherent to these processes, methods, products or devices.

T-GM: T GrandMaster, Master Clock

T-TC: T TransparentClock, transparent clock

T-SC: TSlaveClock, slave clock

PPS: PulsePerSecond, second pulse

ToD: TimeofDay, current time

Example 1

According to this embodiment, an embodiment of a method for synchronizing a clock frequency of a metering device is also provided. It should be noted that the steps shown in the flowchart of the accompanying drawings may be executed in a computer system such as a set of computer-executable instructions, Also, although a logical order is shown in the flowcharts, in some cases the steps shown or described may be performed in an order different from that herein.

The method embodiments provided in this embodiment may be executed in a mobile terminal, a computer terminal, a server, or a similar computing device. FIG. 1 shows a block diagram of a hardware structure of a computing device for implementing a clock frequency synchronization method for a metering device. As shown in FIG. 1, a computing device may include one or more processors (the processors may include, but are not limited to, processing means such as a microprocessor MCU or a programmable logic device FPGA, etc.), a memory for storing data, and a processor for Communication function transmission device. In addition, may also include: display, input/output interface (I/O interface), universal serial bus (USB) port (may be included as one of the ports of the I/O interface), network interface, power supply and/or camera. Those of ordinary skill in the art can understand that the structure shown in FIG. 1 is only a schematic diagram, which does not limit the structure of the above electronic device. For example, a computing device may also include more or fewer components than shown in FIG. 1 , or have a different configuration than that shown in FIG. 1 .

It should be noted that the one or more processors and/or other data processing circuits described above may generally be referred to herein as "data processing circuits". The data processing circuit may be embodied in whole or in part as software, hardware, firmware or any other combination. Furthermore, the data processing circuitry may be a single stand-alone processing module, or incorporated in whole or in part into any of the other elements in the computing device. As referred to in embodiments of the present disclosure, the data processing circuit acts as a kind of processor control (eg, selection of a variable resistance termination path connected to an interface).

The memory can be used to store software programs and modules of the application software, such as the program instruction/data storage device corresponding to the clock frequency synchronization method of the metering device in the embodiment of the present disclosure, the processor runs the software programs and modules stored in the memory, thereby A clock frequency synchronization method of a metering device that executes various functional applications and data processing, that is, realizes the above-mentioned application programs. The memory may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory may further include memory located remotely from the processor, the remote memory being connectable to the computing device through a network. Examples of such networks include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

Transmission means are used to receive or transmit data via a network. Specific examples of the above-mentioned networks may include wireless networks provided by the communication provider of the computing device. In one example, the transmission device includes a network adapter (Network Interface Controller, NIC), which can be connected to other network devices through the base station so as to communicate with the Internet. In one example, the transmission device may be a radio frequency (Radio Frequency, RF) module, which is used for wirelessly communicating with the Internet.

The display may be, for example, a touch screen-style liquid crystal display (LCD) that enables a user to interact with a user interface of the computing device.

It should be noted here that, in some optional embodiments, the computing device shown in FIG. 1 may include hardware elements (including circuits), software elements (including computer code stored on a computer-readable medium), or hardware elements A combination of both components and software components. It should be noted that FIG. 1 is only one example of a specific embodiment, and is intended to illustrate the types of components that may be present in the computing device described above.

FIG. 2A is a schematic diagram of a structural system of a power time code value transmission system using power carrier communication according to the present embodiment. Referring to FIG. 2 , the system includes: a three-level time node, a master clock T-GM, a boundary clock T-BC, and a slave clock T-SC. According to the time synchronization mass transmission process shown in Figure 2A, the standard time node is synchronized with the upper-level time node through the satellite working mode, and is synchronized with the master clock through the 1PPS and ToD interfaces, and then T-GM and T-SC/T-BC The node performs time synchronization through the solution of the present invention, and completes time measurement for each metering device in the entire network. in,

(1) Three-level time node: capture and track the GNSS satellite navigation signal by the common-view unit, recover the time of the navigation satellite system, apply the GNSS common-view principle to obtain the time difference of the second-level node, and output 1PPS pulse signal and ToD (Time of Day) time code signal.

(2) T-GM (T-GrandMaster master clock): the master node and master clock in the time topology relationship, through which the clock node receives the 1PPS signal output by the third-level time node and the ToD for clock synchronization; this module uses its own TCXO The crystal oscillator and 1PPS perform frequency phase-locking operation to obtain high-precision frequency signals and absolute time transmitted by magnitude.

(3) T-BC (T-Boundary Clock): an intermediate node that may exist in the time topology relationship, usually refers to the relay node that needs to be constructed for communication due to the attenuation of the line signal, and it will also be based on the carrier. The software protocol of the communication completes the frequency and time synchronization between the master node and the relay node.

(4) T-SC (T-Slaver Clock slave clock): The slave node in the time topology relationship, usually the slave clock of the terminal device, completes the communication between the master node or the relay node and the slave node through the software protocol based on carrier communication. Frequency and time synchronization.

In addition, FIG. 2B is a schematic diagram of establishing a time topology relationship between each terminal node based on the power carrier network. Combined with the networking process of the carrier communication link layer, the time topology shown in FIG. 2B is established. In this time topology: T-GM is located at the third-level node. , is the master clock; T-BC is the relay node, which is both the slave clock and the master clock of the next level; T-SC is the end node, which is the slave clock. Then, a synchronization system is established in the entire network.

Under the above operating environment, according to the first aspect of this embodiment, a method for synchronizing a clock frequency of a metering device is provided. FIG. 3 shows a schematic flowchart of the method. Referring to FIG. 3, the method includes:

S301: Detect the network state of the metering device, and determine the network state of the metering device, where the network state includes an online state and an offline state;

S302: Determine the frequency control mode of the metering device according to the network state, wherein the frequency control mode is realized by a preset frequency control module;

S303: Calculate the time delay and time offset between the various metering devices of the metering device, wherein each metering device is respectively provided with a frequency control module;

S304: Synchronize the clock frequency of each metering device of the metering device according to the time delay, time offset and control method.

As described in the background art, at present, the numerous metering devices of the State Grid at the station level lack effective time synchronization means and cannot meet the needs of the smart grid. Therefore, the research on the economical and reliable time-frequency value transfer and time synchronization system in the intelligent distribution network plays a key role in effectively solving a series of problems introduced by the intelligent distribution network.

In view of this, in view of the deficiencies in the prior art and the actual situation that the power grid adopts carrier wave communication, combined with the demand for power time synchronization quantity transmission, the patent of the present invention describes a power time-frequency magnitude value transmission and time synchronization system using a power carrier wave, First, a method for synchronizing the clock frequency of a metering device at the station level is provided. First, the network status of the metering device is detected and the network state of the metering device is determined. The network state includes an online state and an offline state. Status sets different control strategies.

Further, according to the network state, the frequency control mode of the metering device is determined, wherein the frequency control mode is realized by a preset frequency control module. By setting different frequency control strategies for different network states, the problem of traceability of the local frequency source of the metering device is solved, and the frequency accuracy of the metering device under the online condition and the short-term frequency accuracy under the offline condition are ensured.

Further, calculate the time delay and time offset between each metering device of the metering device, wherein each metering device is respectively provided with a frequency control module, so as to calculate the time delay and time offset between the various metering devices of the metering device. , to realize the traceability of absolute time and meet the performance requirements for time synchronization in power informatization.

Further, according to the time delay, time offset and control method, the clock frequency of each metering device of the metering device is synchronized.

Therefore, through the above method, by setting different frequency control strategies for different network states, the problem of traceability of the local frequency source of the metering device is solved, and the frequency accuracy of the metering device in the online condition and the short-term frequency accuracy in the offline condition are ensured. And by calculating the time delay and time offset measurement method between the various metering devices of the metering device, the problem of traceability of absolute time is realized, and the performance requirements for time synchronization in power informatization are met. To achieve the technical effect of accurate time synchronization between the metering devices of the metering device at the platform level. This further solves the technical problem in the prior art that a large number of metering devices at the station level lack effective time synchronization means and cannot meet the needs of the smart grid.

Optionally, according to the network status, the operation of determining the frequency control mode of the metering device includes:

When the network state is online, the frequency control method adopts closed-loop control;

When the network state is offline, the frequency control method adopts open-loop control.

Specifically, referring to Fig. 4, the slave clock performs closed-loop control through the built-in frequency control module and the standard frequency synchronization method decoded from the carrier signal when the network is online (the control selection switch is located at 1 in Fig. 1) to complete the frequency value. Transfer, when it is sensed that the system is offline, the frequency digital adjustment device is turned into open-loop control to ensure local time maintenance (the control selection switch is located at 2).

Optionally, the frequency control module includes: a decoding unit, a time-to-digital conversion unit, a temperature compensation data unit, a temperature compensation control unit, a digital low-pass filtering unit, a voltage-controlled crystal oscillator, and a temperature sensor provided on the voltage-controlled crystal oscillator ,in

The decoding unit is used to decode the carrier signal and determine the standard frequency;

The time-to-digital conversion unit receives the standard frequency from the decoding unit, adjusts the standard frequency according to the local frequency adjustment voltage parameter, and determines the first digital control quantity;

The temperature compensation data unit is used to store the digital control quantity of the voltage-controlled crystal oscillator unit at different temperatures;

The temperature compensation control unit receives the temperature data of the voltage-controlled crystal oscillator from the temperature sensor, receives the first digital control quantity from the time-to-digital conversion unit, and obtains the digital control quantity of the voltage-controlled crystal oscillator corresponding to the temperature data from the temperature compensation data unit , adjust the first digital control amount according to the digital control amount of the voltage-controlled crystal oscillator, and determine the second digital control amount;

The digital low-pass filtering unit receives the second digital control amount from the temperature compensation control unit, and filters and converts the second digital control amount to determine the control voltage signal;

The voltage controlled crystal oscillator receives the control voltage signal from the digital low pass filter unit.

Specifically, as shown in FIG. 3 , the decoding unit completes the function of obtaining the standard frequency from the carrier signal, the time-to-digital conversion unit completes the comparison between the standard frequency and the current frequency difference and converts them into digital control quantities, and digital low-pass filtering filters the digital control quantities and converts them into digital control quantities. Converted into a control voltage signal, the temperature compensation data unit stores the digital control quantity of the voltage controlled crystal oscillator unit at different temperatures, and the temperature compensation control reads data from the temperature compensation data unit according to different temperatures and outputs the digital control quantity of the voltage controlled crystal oscillator. By using the online temperature scale data of the module during the operation of the network, a temperature compensation mechanism for the frequency control module in the offline state of the module is provided, and a low-cost and high-precision maintenance mechanism for the frequency of the clock module in the offline state is provided.

Optionally, the time-to-digital conversion unit receives the standard frequency from the decoding unit, adjusts the standard frequency according to the local frequency adjustment voltage parameter, and determines the operation of the first digital control amount, including:

The slave clock of each metering device in the metering device receives two time synchronization beacons from the master clock, including the first time stamp and the second time stamp for sending the time synchronization beacon twice, and records the third time synchronization beacon that receives the time synchronization beacon twice. Timestamp and fourth timestamp;

The time-to-digital conversion unit of the slave clock determines the local frequency adjustment voltage parameter according to the first time stamp, the second time stamp, the third time stamp and the fourth time stamp;

The digital conversion unit adjusts the standard frequency according to the local frequency adjustment voltage parameter, and determines the first digital control quantity.

Specifically, referring to Fig. 5, the evaluation process of the clock frequency is shown in Fig. 5. The T-GM master clock terminal periodically sends a time synchronization beacon through a carrier wave, and the transmission time and reception time of the synchronization beacon are carried out through the communication physical layer. The time stamp is generated, and the relay node is required to directly forward the synchronization beacon frame at the physical layer to ensure the stability of the forwarding time delay. The synchronization beacon transmission interval is accurate, and the time delay is generally stable. The time interval is consistent with the master clock, and this relationship is used to synchronize the frequency of the slave clock and the master clock. The frequency difference is as follows:

（1）

(1)

Wherein, as shown in FIG. 5 , T _Mi may be the second time stamp T _M1 , T _M0 may be the first time stamp, T _Si may be the fourth time stamp T _S1 , and T _S0 may be the third time stamp.

The slave clock periodically performs the above evaluation process through the time-to-digital conversion unit in Figure 1, and obtains the local frequency adjustment voltage parameter, which is output to the voltage-controlled crystal oscillator unit to complete the closed-loop feedback adjustment process of the slave clock frequency in Figure 1. To achieve frequency locking, complete the real-time value transfer of the frequency.

Optionally, the frequency control module further includes: a control selection unit and a dual control switch, wherein

The control selection unit is arranged between the time-to-digital conversion unit and the digital low-pass filter unit, and is used for generating the frequency control temperature compensation coefficient according to the pre-stored frequency locking control quantities at different temperatures;

The first contact of the dual control switch is arranged between the temperature compensation control unit and the digital low-pass filtering unit, and the second contact is arranged between the control selection unit and the digital low-pass filtering unit.

Specifically, through the built-in frequency control module, the slave clock performs closed-loop control through the standard frequency synchronization method decoded from the carrier signal when the network is online (the control selection switch is located at 1 in Figure 1) to complete the transmission of the frequency value. When off-line, turn the frequency digital adjustment device to open-loop control to ensure local time maintenance (control selector switch is at 2). Therefore, by setting the double-control switch at position 2, the open-loop control in the offline state is realized by controlling the selection unit.

Through the built-in frequency control module, the slave clock performs closed-loop control through online frequency synchronization when the network is online, completes the transmission of frequency values, and records different frequency-locking control quantities at different temperatures as the frequency control temperature for offline open-loop control. compensation factor. When it is perceived that the system is offline, the frequency digital adjustment device is turned into open-loop control, and the temperature compensation coefficient of frequency control obtained from online operation is used to perform temperature compensation control, so as to realize short-time high-precision time self-sustaining of offline nodes at a lower cost .

Optionally, when the network state is an online state, the frequency control mode adopts a closed-loop control operation, and further includes: arranging a dual-control switch on the first contact.

Optionally, when the network state is an offline state, the frequency control mode adopts an operation of open-loop control, and further includes: arranging a dual-control switch on the second contact.

Therefore, the network-on-line closed-loop control and the network-offline open-loop control of the metering device at the station level can be realized through the double-control switch.

Optionally, it also includes: the master clock encrypts and transmits the output frequency of the voltage-controlled crystal oscillator to the slave clock through a national grid encryption algorithm.

Specifically, a digital encryption mechanism is introduced to ensure the integrity, security and availability of the synchronization time information provided by the module. For the ToD signal output to the end user, encryption and authentication interaction are carried out through the national secret algorithm to ensure the integrity, security and availability of the output time information.

Optionally, the operation of calculating the time delay and time offset between the various metering devices of the metering device includes:

The master clock sends a synchronization message to the slave clock, and packs the fifth timestamp sent by the synchronization message;

The slave clock of each metering device in the metering device receives the synchronization message, and records the sixth time stamp of the received synchronization message;

The slave clock sends a delay request message to the master clock, and records the seventh timestamp of sending the delay request message;

The master clock receives the delay request message, records the eighth timestamp of the received delay request message, and packages the eighth timestamp and the delay response message to the slave clock;

The slave clock determines the uplink and downlink time delay and time offset according to the fifth timestamp, the sixth timestamp, the seventh timestamp and the eighth timestamp.

Specifically, referring to Fig. 6, in order to ensure the uplink and downlink symmetry of the time delay, the time delay and time offset synchronization of the nodes in the entire network synchronization are performed in steps. The synchronization starts from T-GM and goes down, and each synchronization Only the adjacent layers are involved. After the synchronization is completed, the boundary clock node acts as the master clock of the next layer node and continues to perform the next layer synchronization until all nodes in the network node are synchronized. The measurement and calculation process in a specific synchronization is as follows: (wherein the fifth timestamp T ₁ , the sixth timestamp T ₂ , the seventh timestamp T ₃ and the eighth timestamp T ₄ )

1) The master clock sends a Synco synchronization message, and when the message is sent, the physical layer of the master node marks the sending packet with an accurate sending time stamp T ₁ , and when the slave node receives the message, the physical layer marks the received message with accurate reception. Timestamp T ₂ , at this time there are timestamps T ₁ and T ₂ on the slave clock side;

2) Then the slave clock sends the delay request message Delay_Req to the master clock end, and when the message is sent out, the physical layer of the slave node adds an accurate sending time stamp T ₃ to the sending packet, and the slave clock end records T ₃ , At this time, the slave The clock end has timestamps T ₁ , T ₂ and T ₃ ;

3) Finally, when the master clock side receives the delay request message Delay_Req, the physical layer marks the received message with an accurate reception time stamp T ₄ , and sends the T ₄ time stamp information to the slave clock through the delay response message Delay_Resp, and is sent by the slave clock. The clock records time, and the slave clock side has timestamps T ₁ , T ₂ , T ₃ and T ₄ at this time.

Among them, the time T1 and T4 are _measured by the time information _of the master clock, while the time T2 and _T3 are measured by the time information _of the slave clock, which are uniformly measured by the standard of the master clock . Assuming that the master clock There is a time offset with a time length of T _offset from the slave clock, and the upstream and downstream transmission delays of the path are T _delay1 and T _delay2 , the following equation can be obtained:

(2)

(2)

(3)

(3)

(4)

(4)

Since the above transmission delay is performed at the transmission physical layer and is only related to the distance between two points of carrier communication, the uplink and downlink transmission delays T _delay1 and T _delay2 are equal, and the time delay and time offset can be calculated:

（5）

(5)

（6）

(6)

The slave clock performs absolute time correction of the slave clock according to T _offset , and completes the transfer of the absolute time value to the slave clock. The above method solves the problem of delay uncertainty and accumulated error caused by the delay of the device application layer in the carrier communication transmission, guarantees the time synchronization accuracy, and realizes the transmission of absolute time value.

In addition, referring to FIG. 1 , according to a second aspect of the present embodiment, a storage medium is provided. The storage medium includes a stored program, wherein the method described in any one of the above is executed by the processor when the program is executed.

Therefore, according to this embodiment, by setting different frequency control strategies for different network states, the problem of traceability of the local frequency source of the metering device is solved, and the frequency accuracy of the metering device is ensured online and short-term frequency accuracy offline. And by calculating the time delay and time offset measurement method between the various metering devices of the metering device, the problem of traceability of absolute time is realized, and the performance requirements for time synchronization in power informatization are met. To achieve the technical effect of accurate time synchronization between the metering devices of the metering device at the platform level. This further solves the technical problem in the prior art that a large number of metering devices at the station level lack effective time synchronization means and cannot meet the needs of the smart grid.

In addition, the present invention provides a highly reliable and high-precision time synchronization mass transmission system based on carrier communication, which solves the urgent need for high-precision time synchronization required for the digital informatization of the power grid, and can meet the application needs of various power scenarios. Strong applicability; provides a clock frequency synchronization method to ensure the transmission of the value of the clock frequency between the master clock and the slave clock; provides a time delay and time offset measurement method, which solves the problem of carrier communication The delay uncertainty and accumulated error caused by the delay of the device application layer in the transmission ensure the accuracy of time synchronization and realize the transmission of absolute time value; by using the online temperature scale data of the module during the network operation, a module is provided. The temperature compensation mechanism of the frequency control module in the offline situation provides a low-cost and high-precision maintenance mechanism for the frequency of the clock module when offline; the digital encryption mechanism is introduced to ensure the integrity, security and availability of the synchronization time information provided by the module to the outside world. .

It should be noted that, for the sake of simple description, the foregoing method embodiments are all expressed as a series of action combinations, but those skilled in the art should know that the present invention is not limited by the described action sequence. As in accordance with the present invention, certain steps may be performed in other orders or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

From the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is better implementation. Based on this understanding, the technical solutions of the present invention essentially or the parts that contribute to the prior art can be embodied in the form of software products, and the computer software products are stored in a storage medium (such as ROM/RAM, magnetic disk, CD-ROM), including several instructions to make a terminal device (which may be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present invention.

Example 2

FIG. 7 shows a clock frequency synchronization device 700 of the metering device according to this embodiment, and the device 700 corresponds to the method according to the first aspect of the first embodiment. Referring to FIG. 7 , the device 700 includes: a first determination module 710 for detecting the network status of the metering device and determining the network status of the metering device, wherein the network status includes an online status and an offline status; the second determination module 720 is configured with According to the network state, the frequency control mode of the metering device is determined, wherein the frequency control mode is realized by a preset frequency control module; the calculation module 730 is used to calculate the time delay and time offset between the various metering devices of the metering device, wherein Each metering device is respectively provided with a frequency control module; the synchronization module 740 is used for synchronizing the clock frequency of each metering device of the metering device according to the time delay, time offset and control mode.

Optionally, the second determining module 720 includes: a first adopting sub-module for adopting closed-loop control in the frequency control mode when the network state is an online state; In the case of the state, the frequency control method adopts open-loop control.

Optionally, the network state includes an online state and an offline state, and the second determining module includes: a first adopting sub-module for, when the network state is the online state, the frequency control mode Closed-loop control is adopted; secondly, a sub-module is adopted, which is used for adopting open-loop control in the frequency control mode when the network state is the offline state.

Optionally, the second determination module includes: a first determination sub-module, configured to determine the frequency control mode of the metering device according to the network state through a preset frequency control module.

Optionally, the first adopting sub-module includes: a first determining unit, configured to decode the carrier signal by using the frequency control module, and determine a standard frequency; a second determining unit, configured to use the frequency control module to determine the standard frequency according to the The local frequency adjustment voltage parameter adjusts the standard frequency to determine the first digital control quantity; the fourth determination unit is used for using the frequency control module to filter and convert the second digital control quantity to determine the control voltage signal ; a fifth determining unit, configured to adjust the voltage-controlled crystal oscillator unit through the voltage control information to determine the output clock frequency.

Optionally, the second adopting sub-module includes: a sixth determining unit, configured to decode the carrier signal by using the frequency control module to determine the standard frequency; and a seventh determining unit, configured to use the frequency control module to determine the standard frequency according to the The local frequency adjustment voltage parameter adjusts the standard frequency to determine the first digital control quantity; the eighth determination unit is used for using the frequency control module to generate frequency control according to the pre-stored frequency locking control quantities at different temperatures temperature compensation coefficient, and adjust the first digital control amount to generate a third digital control amount; a ninth determination unit is used to filter and convert the third digital control amount by using the frequency control module, and determine a control voltage signal; and a tenth determination unit, configured to adjust the voltage-controlled crystal oscillation unit through the voltage control information to determine an output clock frequency.

Optionally, the first determination sub-module includes: a first recording unit, used for the slave clock of each metering device in the metering device to receive two time synchronization beacons from the master clock, including sending the two time synchronization beacons. the first time stamp and the second time stamp of the time synchronization beacon, and record the third time stamp and the fourth time stamp of the time synchronization beacon received twice; the eleventh determination unit is used for the The time-to-digital conversion unit determines a local frequency adjustment voltage parameter according to the first time stamp, the second time stamp, the third time stamp and the fourth time stamp; a twelfth determination unit is used for the The digital conversion unit adjusts the standard frequency according to the local frequency adjustment voltage parameter, and determines the first digital control quantity.

Optionally, the second determination module further includes: an implementation sub-module configured to implement the frequency control mode through a dual-control switch preset in the frequency control module.

Optionally, the apparatus 700 further includes: an encryption module, used for the master clock to encrypt and transmit the output frequency of the voltage-controlled crystal oscillator to the slave clock through a national grid encryption algorithm.

Optionally, the computing module 730 includes: a first sending submodule, used for the master clock to send a synchronization message to the slave clock, and packaging the fifth time stamp sent by the synchronization message; a first receiving submodule, used for the metering device The slave clock of each metering device in the device receives the synchronization message, and records the sixth time stamp of the received synchronization message; the second sending sub-module is used to send the delay request message from the clock to the master clock, and records the sending delay request message. The second receiving sub-module is used for the master clock to receive the delay request message, record the eighth timestamp of the received delay request message, and package the eighth timestamp and the delay response message to the slave. a clock; a second determination submodule for determining the time delay and time offset of the uplink and downlink from the clock according to the fifth timestamp, the sixth timestamp, the seventh timestamp and the eighth timestamp.

Therefore, according to this embodiment, by setting different frequency control strategies for different network states, the problem of traceability of the local frequency source of the metering device is solved, and the frequency accuracy of the metering device is ensured online and short-term frequency accuracy offline. And by calculating the time delay and time offset measurement method between the various metering devices of the metering device, the problem of traceability of absolute time is realized, and the performance requirements for time synchronization in power informatization are met. To achieve the technical effect of accurate time synchronization between the metering devices of the metering device at the platform level. This further solves the technical problem in the prior art that a large number of metering devices at the station level lack effective time synchronization means and cannot meet the needs of the smart grid.

Example 3

FIG. 8 shows a clock frequency synchronization apparatus 800 of the metering apparatus according to the present embodiment, the apparatus 800 corresponding to the method according to the first aspect of Embodiment 1. As shown in FIG. Referring to FIG. 8, the device 800 includes: a processor 810; and a memory 820, connected to the processor 810, for providing the processor 810 with instructions for processing the following processing steps: detecting the network status of the metering device, determining the network status of the metering device Network status, wherein the network status includes online status and offline status; according to the network status, determine the frequency control mode of the metering device, wherein the frequency control mode is realized by a preset frequency control module; calculate the time delay between each metering device of the metering device and time offset, wherein each metering device is respectively provided with a frequency control module; according to the time delay, time offset and control mode, the clock frequency of each metering device of the metering device is synchronized.

Optionally, according to the network state, determine the operation of the frequency control mode of the metering device, including: when the network state is an online state, the frequency control mode adopts closed-loop control; when the network state is an offline state, the frequency control mode. Open loop control is used.

Optionally, the frequency control module includes: a decoding unit, a time-to-digital conversion unit, a temperature compensation data unit, a temperature compensation control unit, a digital low-pass filtering unit, a voltage-controlled crystal oscillator, and a temperature sensor provided on the voltage-controlled crystal oscillator , wherein the decoding unit is used to decode the carrier signal and determine the standard frequency; the time-to-digital conversion unit receives the standard frequency from the decoding unit, and adjusts the standard frequency according to the local frequency adjustment voltage parameter to determine the first digital control amount; temperature compensation data The unit is used to store the digital control quantity of the voltage-controlled crystal oscillator unit at different temperatures; the temperature compensation control unit receives the temperature data of the voltage-controlled crystal oscillator from the temperature sensor, and receives the first digital control quantity from the time-to-digital conversion unit, and receives the temperature compensation from the temperature compensation unit. The data unit obtains the digital control quantity of the voltage-controlled crystal oscillator corresponding to the temperature data, adjusts the first digital control quantity according to the digital control quantity of the voltage-controlled crystal oscillator, and determines the second digital control quantity; The control unit receives the second digital control quantity, and filters and converts the second digital control quantity to determine the control voltage signal; the voltage-controlled crystal oscillator receives the control voltage signal from the digital low-pass filtering unit.

Optionally, the time-to-digital conversion unit receives the standard frequency from the decoding unit, and adjusts the standard frequency according to the local frequency adjustment voltage parameter, and determines the operation of the first digital control amount, including: the slave clock of each metering device in the metering device The master clock receives the time synchronization beacon twice, including the first timestamp and the second timestamp of the time synchronization beacon sent twice, and records the third timestamp and the fourth timestamp of the time synchronization beacon received twice; The time-to-digital conversion unit determines the local frequency adjustment voltage parameter according to the first time stamp, the second time stamp, the third time stamp and the fourth time stamp; the digital conversion unit adjusts the standard frequency according to the local frequency adjustment voltage parameter, and determines the first time stamp Digital control volume.

Optionally, the frequency control module further includes: a control selection unit and a dual-control switch, wherein the control selection unit is arranged between the time-to-digital conversion unit and the digital low-pass filter unit, and is used for frequency locking control according to pre-stored different temperatures. The first contact of the dual control switch is set between the temperature compensation control unit and the digital low-pass filtering unit, and the second contact is set between the control selection unit and the digital low-pass filtering unit.

Optionally, when the network state is an online state, the frequency control mode adopts a closed-loop control operation, and further includes: arranging a dual-control switch on the first contact.

Optionally, when the network state is an offline state, the frequency control mode adopts an operation of open-loop control, and further includes: arranging a dual-control switch on the second contact.

Optionally, the memory 820 is further configured to provide the processor 810 with instructions for processing the following processing steps: the master clock encrypts and transmits the output frequency of the voltage-controlled crystal oscillator to the slave clock through a national grid encryption algorithm.

Optionally, the operation of calculating the time delay and time offset between various metering devices of the metering device includes: the master clock sends a synchronization message to the slave clock, and packages the fifth time stamp sent by the synchronization message; The slave clock of each metering device receives the synchronization message, and records the sixth time stamp of the received synchronization message; the slave clock sends the delay request message to the master clock, and records the seventh time stamp of the delay request message; the master clock Receive the delay request message, record the eighth timestamp of the received delay request message, and package the eighth timestamp and the delay response message to the slave clock; the slave clock is based on the fifth timestamp, sixth timestamp, seventh timestamp The timestamp and the eighth timestamp determine the time delay and time offset of the uplink and downlink.

Therefore, according to this embodiment, by setting different frequency control strategies for different network states, the problem of traceability of the local frequency source of the metering device is solved, and the frequency accuracy of the metering device is ensured online and short-term frequency accuracy offline. And by calculating the time delay and time offset measurement method between the various metering devices of the metering device, the problem of traceability of absolute time is realized, and the performance requirements for time synchronization in power informatization are met. To achieve the technical effect of accurate time synchronization between the metering devices of the metering device at the platform level. This further solves the technical problem in the prior art that a large number of metering devices at the station level lack effective time synchronization means and cannot meet the needs of the smart grid.

The above-mentioned serial numbers of the embodiments of the present invention are only for description, and do not represent the advantages or disadvantages of the embodiments.

In the above-mentioned embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

In the several embodiments provided by the present invention, it should be understood that the disclosed technical content may be implemented in other ways. The apparatus embodiments described above are only illustrative, for example, the division of the units is only a logical function division, and there may be other division methods in actual implementation, for example, multiple units or components may be combined or Integration into another system, or some features can be ignored, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of units or modules, and may be in electrical or other forms.

The units described as separate components may or may not be physically separated, and components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated units may be implemented in the form of hardware, or may be implemented in the form of software functional units.

The integrated unit, if implemented in the form of a software functional unit and sold or used as an independent product, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium , including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes .

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. It should be regarded as the protection scope of the present invention.

Claims (20)

1. a clock frequency synchronization method of a metering device, applied between each metering equipment of the metering device in the platform level, is characterized in that, comprising: Detecting the network status of the metering device, and determining the network status of the metering device; Determine the frequency control mode of the metering device according to the network state; calculating the time delay and time offset between the various metering devices of the metering device; According to the time delay, the time offset, and the control method, clock frequency synchronization is performed on each of the metering devices of the metering apparatus. 2. The method of claim 1, wherein the network state includes an online state and an offline state, and According to the network state, the operation of determining the frequency control mode of the metering device includes: When the network state is the online state, the frequency control method adopts closed-loop control; When the network state is the offline state, the frequency control method adopts open-loop control. 3. The method according to claim 2, wherein, according to the network state, determining the operation of the frequency control mode of the metering device comprises: The frequency control mode of the metering device is determined according to the network state through a preset frequency control module. 4 . The method according to claim 3 , wherein, when the network state is the online state, the frequency control mode adopts a closed-loop control operation, comprising: 5 . Use the frequency control module to decode the carrier signal to determine the standard frequency; Using the frequency control module, the standard frequency is adjusted according to the local frequency adjustment voltage parameter, and the first digital control quantity is determined; Utilize the frequency control module to adjust the first digital control quantity through the collected temperature data of the voltage-controlled crystal oscillator unit, and determine the second digital control quantity; Using the frequency control module, filter and convert the second digital control variable to determine a control voltage signal; According to the voltage control information, the voltage-controlled crystal oscillator unit is adjusted to determine the output clock frequency. 5. The method according to claim 3, wherein, when the network state is the offline state, the frequency control method adopts open-loop control, comprising: Use the frequency control module to decode the carrier signal to determine the standard frequency; Using the frequency control module, the standard frequency is adjusted according to the local frequency adjustment voltage parameter, and the first digital control quantity is determined; Using the frequency control module, according to the pre-stored frequency-locking control quantities at different temperatures, a frequency control temperature compensation coefficient is generated, and the first digital control quantity is adjusted to generate a third digital control quantity; Using the frequency control module, filtering and converting the third digital control variable to determine a control voltage signal; According to the voltage control information, the voltage-controlled crystal oscillator unit is adjusted to determine the output clock frequency. 6. The method according to any one of claims 4 or 5, wherein the frequency control module is used to adjust the standard frequency according to a local frequency adjustment voltage parameter to determine the operation of the first digital control quantity, include: The slave clock of each metering device in the metering device receives two time synchronization beacons from the master clock, including the first time stamp and the second time stamp for sending the two time synchronization beacons, and records the received time synchronization beacons. The third timestamp and the fourth timestamp of the two time synchronization beacons; The time-to-digital conversion unit of the slave clock determines a local frequency adjustment voltage parameter according to the first time stamp, the second time stamp, the third time stamp and the fourth time stamp; The digital conversion unit adjusts the standard frequency according to the local frequency adjustment voltage parameter, and determines the first digital control quantity. 7. The method according to claim 3, wherein, according to the network state, determining the operation of the frequency control mode of the metering device, further comprising: The frequency control mode is realized by a dual-control switch preset in the frequency control module. 8. The method of claim 6, further comprising: The master clock encrypts and transmits the output frequency of the voltage-controlled crystal oscillator to the slave clock through a national network encryption algorithm. 9. The method according to claim 6, wherein the operation of calculating the time delay and time offset between the various metering devices of the metering device comprises: The master clock sends a synchronization message to the slave clock, and packages the fifth timestamp sent by the synchronization message; The slave clock of each metering device in the metering device receives the synchronization message, and records a sixth time stamp of receiving the synchronization message; The slave clock sends a delay request message to the master clock, and records a seventh timestamp for sending the delay request message; The master clock receives the delay request message, records an eighth timestamp of receiving the delay request message, and packages the eighth timestamp and the delay response message to the slave clock; The slave clock determines the uplink and downlink time delay and the time offset according to the fifth timestamp, the sixth timestamp, the seventh timestamp and the eighth timestamp. 10. A computer-readable storage medium, characterized in that the storage medium comprises a stored program, wherein the method according to any one of claims 1 to 9 is executed by a processor when the program is executed. 11. A clock frequency synchronizing device of a metering device, applied between each metering equipment of the metering device in the platform level, is characterized in that, comprising: a first determining module, configured to detect the network status of the metering device, and determine the network status of the metering device; a second determining module, configured to determine a frequency control mode of the metering device according to the network state, wherein the frequency control mode is implemented by a preset frequency control module; a calculation module, configured to calculate the time delay and time offset between the various measurement devices of the measurement device, wherein each of the measurement devices is respectively provided with the frequency control module; A synchronization module, configured to synchronize the clock frequencies of the various metering devices of the metering device according to the time delay, the time offset and the control method. 12. The apparatus according to claim 11, wherein the network state includes an online state and an offline state, and the second determining module comprises: The first adopts a sub-module, which is used to adopt closed-loop control for the frequency control mode when the network state is the online state; The second adopts a sub-module, which is used for adopting open-loop control in the frequency control mode when the network state is the offline state. 13. The apparatus according to claim 12, wherein the second determining module comprises: The first determination sub-module is configured to determine the frequency control mode of the metering device according to the network state through a preset frequency control module. 14. The device according to claim 13, wherein the first adopting sub-module comprises: a first determining unit, configured to decode the carrier signal by using the frequency control module to determine a standard frequency; a second determining unit, configured to use the frequency control module to adjust the standard frequency according to the local frequency adjustment voltage parameter to determine the first digital control quantity; a fourth determining unit, configured to use the frequency control module to filter and convert the second digital control quantity to determine a control voltage signal; The fifth determining unit is configured to adjust the voltage-controlled crystal oscillation unit according to the voltage control information to determine the output clock frequency. 15. The apparatus according to claim 13, wherein the second adopting sub-module comprises: a sixth determining unit, configured to decode the carrier signal by using the frequency control module to determine the standard frequency; a seventh determination unit, configured to use the frequency control module to adjust the standard frequency according to the local frequency adjustment voltage parameter, and determine the first digital control quantity; The eighth determination unit is used for using the frequency control module to generate a frequency control temperature compensation coefficient according to the pre-stored frequency locking control quantities at different temperatures, and to adjust the first digital control quantity to generate a third digital control quantity. Control amount; a ninth determination unit, configured to use the frequency control module to filter and convert the third digital control quantity to determine a control voltage signal; The tenth determining unit is configured to adjust the voltage-controlled crystal oscillation unit according to the voltage control information to determine the output clock frequency. 16. The apparatus according to any one of claims 14 or 15, wherein the first determination submodule comprises: a first recording unit, used for the slave clock of each metering device in the metering device to receive two time synchronization beacons from the master clock, including a first time stamp and a second time for sending the two time synchronization beacons stamp, and record the third time stamp and the fourth time stamp of receiving the two time synchronization beacons; Eleventh determining unit, wherein the time-to-digital conversion unit for the slave clock determines the local time stamp according to the first time stamp, the second time stamp, the third time stamp and the fourth time stamp Frequency adjustment voltage parameters; A twelfth determination unit is used for the digital conversion unit to adjust the standard frequency according to the local frequency adjustment voltage parameter to determine the first digital control quantity. 17. The apparatus according to claim 13, wherein the second determining module further comprises: The realization sub-module is used to realize the frequency control mode through the dual-control switch preset in the frequency control module. 18. The apparatus of claim 16, further comprising: The encryption module is used for the master clock to encrypt and transmit the output frequency of the voltage-controlled crystal oscillator to the slave clock through the national network encryption algorithm. 19. The apparatus according to claim 16, wherein the computing module comprises: a first sending submodule, used for the master clock to send a synchronization message to the slave clock, and to package a fifth time stamp sent by the synchronization message; a first receiving sub-module, used for receiving the synchronization message from the clock of each metering device in the metering device, and recording the sixth time stamp of receiving the synchronization message; a second sending submodule, used for the slave clock to send a delay request message to the master clock, and to record a seventh time stamp for sending the delay request message; The second receiving submodule is used for the master clock to receive the delay request message, record the eighth timestamp of receiving the delay request message, and package and send the eighth timestamp and the delay response message to the slave clock; The second determination submodule is used for the slave clock to determine the uplink and downlink time delay and the time delay according to the fifth timestamp, the sixth timestamp, the seventh timestamp and the eighth timestamp time offset. 20. A clock frequency synchronization device of a metering device, which is applied between each metering equipment of the metering device in the platform level, characterized in that it comprises: processor; and a memory, connected to the processor, for providing the processor with instructions for processing the following processing steps: Detecting the network status of the metering device, and determining the network status of the metering device; Determine the frequency control mode of the metering device according to the network state, wherein the frequency control mode is realized by a preset frequency control module; calculating the time delay and time offset between the various metering devices of the metering device, wherein each of the metering devices is respectively provided with the frequency control module; According to the time delay, the time offset, and the control method, clock frequency synchronization is performed on each of the metering devices of the metering apparatus.

Images