CN102592431B - Meter reading system and method thereof - Google Patents

Abstract

The invention discloses a meter reading system which comprises a power line wideband carrier communication unit, a wireless communication unit, a clock unit, a control unit and a storage unit. The power line wideband carrier communication unit is used for transceiving a meter reading signal transmitted in a power line carrier way; the wireless communication unit is used for transceiving a meter reading signal transmitted in a wireless communication way; and the control unit is used for detecting a channel condition, controlling the meter reading system to automatically switch channels between the power line wideband carrier communication and the wireless communication according to a detection result, carrying out automatic networking after switching the channels and carrying out format conversion on the meter reading signals received from the power line wideband carrier communication unit and the wireless communication unit to generate electric meter data. The meter reading system combines the wireless communication way with the power line communication way by utilizing the characteristics of high reliability of the wideband carrier communication, high data transmission rate, large data capacity, bidirectional transmission and the like, so that the field construction work such as reading an electric meter, arranging wires and the like is simple, convenient and flexible.

Description

Meter reading system and method

technical field

The invention relates to a meter reading technology, in particular to a meter reading system and a method thereof which combine wireless communication and power line carrier transmission modes of power line carrier and wireless communication.

Background technique

In recent years, with the development of the national urban and rural power grid transformation and implementation of one household, one meter project, the number of single-phase watt-hour meters installed has increased sharply. The biggest problem that has been brought about is that the manual meter reading mode that the Ministry of Electric Power has followed for a long time can no longer adapt. This change gave birth to the remote meter reading mode. Remote meter reading methods generally include RS485 meter reading methods, infrared meter reading methods, low-voltage narrowband carrier meter reading methods, low-voltage broadband carrier meter reading methods, and short-distance wireless meter reading methods.

Among many meter reading devices, manual hand-held meter reading is inefficient, heavy workload, poor accuracy and real-time efficiency; RS485 meter reading method requires wiring, construction and wiring work is heavy, and after the communication channel is damaged, troubleshooting is difficult ;Using the infrared meter reading method, limited by the distance transmission, still needs people to go to the scene. In addition, the infrared meter reading also has high requirements on the azimuth and the environment; the low-voltage narrow-band carrier meter reading method has large signal attenuation, many noise sources and strong interference. , Affected by problems such as the large impact of load characteristics, certain technical obstacles have been formed on the reliability of communication, and due to the narrow bandwidth and low data transmission rate, it is not conducive to large-scale promotion of residents' centralized meter reading of power user information collection systems; The low-voltage broadband carrier meter reading method has the problem of fast attenuation of high-frequency signals. In long-distance communication, intermediate networking is required to solve the transmission. Moreover, due to the influence of the structure and load of the low-voltage power line itself, the reading is successful during the peak period of power consumption. rate is affected. The short-distance wireless meter reading method is greatly affected by the climate and environment. Once it encounters wind and rain or other transmitters in the residential area are turned on, it will be interfered, and it is prone to blockage during peak traffic hours during holidays. Phenomena, so the randomness and uncertainty are very large.

In addition, the acquisition device using the power line carrier technology to transmit data is widely adopted because of its high efficiency, easy management, and the establishment of a sound billing method. However, the current carrier wave collectors have defects in different degrees in practical applications, such as the "Intelligent Carrier Meter Reading Device" with the patent No. Carrier technology realizes the reading and transmission of electricity from electric meters. Their communication methods are relatively simple, their anti-interference ability is poor, and they have high requirements for the transmission quality of power lines. Moreover, their products are generally only available in small areas with less grid interference. Certain practical value, when used in a large area, due to the large interference of the power grid, they will all have a low copying success rate, the signal is drowned by noise, and the power cannot be copied.

Power carrier wave communication technology has been perfected for a long time, and has been quite mature in some fields, and can be used to transmit a lot of real-time data. The advantage is that there is no need to re-establish the network, and the power lines carried by various devices can be used for signal transmission. However, there is noise interference on the power line, and the environment of the power line is also dynamically changing. The interference to the signal is different at different times, and the transmission range is small. Therefore, it is not suitable for power line carrier technology to be used in many occasions.

Wireless communication is a communication method that uses the characteristics that electromagnetic wave signals can propagate in free space for information exchange. At present, there have been many methods of smart meter reading using wireless communication methods, such as WIFI, etc. These wireless communication methods have greatly promoted smart meter reading. However, in the case where the distance is short but there are many large solid obstacles in the space, and the wireless signal is difficult to transmit, using a wireless communication network for signal transmission will have a greater impact on the reliability of communication.

Contents of the invention

The technical problem mainly solved by the present invention is to provide a meter reading system that can automatically select the appropriate data transmission mode according to different situations and requirements on site, thereby expanding the scope of use, combining different transmission modes, and enhancing communication efficiency. reliability. The meter reading system relies on the user's original power line network and does not require secondary wiring, making on-site construction work such as meter reading wiring simple and flexible.

In order to solve the above technical problems, a technical solution adopted by the present invention is: provide a meter reading system, including a power line broadband carrier communication unit, a wireless communication unit, a clock unit, a control unit and a storage unit; the power line broadband carrier communication unit, The wireless communication unit, the clock unit and the storage unit are all connected to the control unit; the power line broadband carrier communication unit is used to send and receive the meter reading signal transmitted by the broadband power line carrier; the wireless communication unit is used to send and receive the meter reading signal transmitted by wireless communication The meter reading signal; the control unit is used to detect the channel status of the power line. According to the detection results, the meter reading system is controlled to automatically switch channels between broadband power carrier communication and wireless communication. The format conversion of the meter reading signal received by the power line broadband carrier communication unit and the wireless communication unit generates meter data; the clock unit provides a clock trigger signal for the control unit; the storage unit is used to store the meter data of the control unit and store the power line broadband carrier communication The control command of the unit and the channel switching of the wireless communication unit stores the control parameters of the power line channel status detection.

Wherein, the control unit includes a data calculation unit, a logic judgment unit, and a cache unit; the data calculation unit is used for real-time monitoring of broadband power line channel conditions, and format conversion for meter reading signals; the logic judgment unit is used for power line Judging the channel status, managing the network channel switching of the broadband power line carrier unit and the wireless communication unit; the cache unit is used for buffer storage of the control parameters of the control unit and the data of the electric meter.

Wherein, the storage unit includes RAM and FLASH; the RAM is used to store the data of the electric meter; and the FLASH is used to store the control parameters of the control unit.

Wherein, the clock unit is an RTC clock unit.

In order to solve the above-mentioned technical problems, the present invention also adopts a kind of meter reading method, comprises the following steps:

Step 1: send and receive the signal of meter reading through the power line; the communication signal includes the signal-to-noise ratio and the packet loss rate in the communication channel;

Step 2: periodically detect the power line channel status, judge the current power line channel status according to the received communication signal of meter reading, if the power line communication is normal, then loop step 2, if the power line communication is abnormal, then go to step 3;

Step 3: Perform channel automatic switching between power line broadband carrier communication and wireless communication, and send and receive communication signals for meter reading in a wireless manner;

Step 4: The meter reading system intermittently detects the power line channel status, and judges the current power line channel status according to the received communication signal of the meter reading. If the power line communication is normal, return to step 1. If the power line communication is abnormal, go to step 3.

In step 2, the criteria for judging the communication status are: when the signal-to-noise ratio in the power line communication channel is lower than a predetermined threshold or the packet loss rate of the meter reading system when receiving signals is greater than 20%, it is considered abnormal communication.

Further, in step 2, the period is configurable, and the default value is 5 minutes.

In step 4, the criterion for judging the communication situation is: when the signal-to-noise ratio in the communication channel is less than a predetermined threshold or the packet loss rate when the meter reading system receives the signal is greater than 5%, it is considered abnormal communication.

Further, in step 4, the intermittent time is a configurable time, and the default value is 30 minutes.

The beneficial effects of the present invention are: different from the single function of the traditional meter reading system, the meter reading system of the technical solution has powerful software functions, the control unit has functions such as automatic channel switching and automatic networking, and automatically performs network judgment. Realize the network switching of the power line broadband carrier communication unit and the wireless communication unit. When the power line environment is good, the power line carrier meter reading is mainly used. When the power line environment deteriorates or there are special requirements, it will automatically switch to the wireless meter reading method to ensure an efficient data transmission rate. The control unit continuously detects the communication status of the power line. When the power line communication is normal, the power line broadband carrier is preferred for communication, which ensures that the staff can work efficiently. In addition, this system relies on the user's original power line network, uses the frequency band used by broadband carrier communication to interfere less on the power line, has higher communication reliability, more stability, better security, and communication occupies frequency bandwidth and high data transmission rate , large data capacity, two-way transmission, so that no secondary wiring is required, the power communication network can be easily extended to the low-voltage user side, and the data collection of the user's electric meter can be realized, and the adaptability is good. Combining the advantages of the wireless communication unit's network adaptability and strong ability to bypass obstacles in use, the combination of the two not only effectively improves the level of automation and informatization, but also facilitates the large-scale promotion of electricity consumption information collection for power users. While ensuring efficient data transmission rate, it makes on-site construction work such as meter reading and wiring easy and flexible. When the power line environment deteriorates or there are special requirements, it will automatically switch to wireless meter reading.

Description of drawings

Fig. 1 is the structural representation of the meter reading system of technical solution of the present invention;

Fig. 2 is a flow chart of the meter reading method of the technical solution of the present invention.

Detailed ways

In order to describe the technical content, structural features, achieved goals and effects of the present invention in detail, the following will be described in detail in conjunction with the embodiments and accompanying drawings.

Please refer to Fig. 1, a kind of meter reading system provided by the present invention includes a power line broadband carrier communication unit, a wireless communication unit, a clock unit, a control unit and a storage unit; the power line broadband carrier communication unit, a wireless communication unit, a clock unit and The storage units are all connected with the control unit; the power line broadband carrier communication unit is used to receive the meter signal sent by the broadband power line carrier; the wireless communication unit is used to receive the meter reading signal sent by wireless communication; the control unit uses In the detection of power line channel conditions, according to the detection results, the meter reading system is controlled to automatically switch channels between broadband power carrier communication and wireless communication. The meter reading signal received by the unit is format-converted to generate meter data; the clock unit provides a clock trigger signal for the control unit; the storage unit is used to store the meter data of the control unit, store the power line broadband carrier communication unit and the channel switching of the wireless communication unit The control command stores control parameters of power line channel status detection. The control unit adopts a mainstream microprocessor, and the data calculation unit is used for real-time monitoring of the broadband power line channel status, and format conversion for the meter reading signal; the logic judgment unit is used for judging the power line channel status and managing the broadband The network channel switching of the power line carrier unit and the wireless communication unit; the cache unit is used for the buffer storage of the control parameters of the control unit and the data of the electric meter.

During the working process, when the power line communication is normal, the meter reading system communicates with the meter through the broadband power line carrier unit. When the power line communication is abnormal, the power line broadband carrier communication unit and the wireless communication unit send control to the control unit through the data bus. signal, after the control unit receives the control signal, it judges whether it is necessary to switch the communication mode through the data calculation unit and the logic judgment unit. Wireless communication, and re-networking. After communicating through wireless communication, the control unit still detects the channel condition of the power line in real time. During the communication process between the meter reading system and the electric meter, the control unit collects the meter reading signal received by the power line broadband carrier communication unit and the wireless communication unit, converts the format to generate electric meter data, and temporarily stores the electric meter data in the cache unit, and finally saves the electric meter Data is stored in storage units. Specifically, the storage unit includes RAM and FLASH; the RAM is used to store the data of the electric meter; the FLASH is used to store the control parameters of the control unit. The FLASH adopts the mainstream FLASH chip to ensure the storage and reading of control parameters, etc. The RAM also adopts the mainstream RAM chip to store the meter reading and some cache information. After the meter reading system switches the communication mode, it re-collects the meter data , and stored in RAM, the data of the meter in RAM is updated in real time. When working, FLASH stores the control parameters of the control unit, such as channel automatic switching, automatic networking and other control parameters. When the control unit needs to perform switching control, the control unit obtains the control parameters from the FLASH memory, and then executes the automatic channel switching. process. The physical characteristics of FLASH are fundamentally different from common memory: at present, all kinds of DDR, SDRAM or RDRAM are volatile memories, and the data in the memory cannot be kept as long as the current supply is stopped, so the data needs to be reloaded every time the computer is turned on. Flash memory can keep data for a long time without current supply, and its storage characteristics are equivalent to hard disks. The control commands of the control unit are stored in FLASH, so as to ensure the high-speed operation of the control unit and the meter reading system. normal operation. RAM is used to store the meter readings and buffer information, which is convenient for the staff to track the data of the meter in real time. The control unit uses the clock unit to count the time, and regularly detects the current communication situation within the specified time, so as to decide whether to switch the communication mode. Specifically, the clock unit is an RTC clock unit, and the RTC clock is accurate in timing, ensuring timely reading of data and freezing of data. The control unit pre-stores the current electric meter reading and control parameters in the cache unit, and then the control unit transmits the data in the cache unit to the external storage unit.

Referring to Fig. 2, this technical solution also provides a kind of meter reading method, and this method comprises the following steps:

Step 1: Send and receive meter reading signals through the power line;

Step 2: Periodically detect the power line channel status, judge the current power line channel status according to the received communication signal, if the power line communication is normal, then loop step 2, if the power line communication is abnormal, then go to step 3; the communication status judgment standard is : When the signal-to-noise ratio in the power line communication channel is lower than the predetermined threshold or the packet loss rate when the meter reading system receives the signal is greater than 20%, it is considered abnormal communication. The cycle is configurable, and the default value is 5 minutes;

Step 3: Perform channel automatic switching between power line broadband carrier communication and wireless communication, and send and receive communication signals for meter reading in a wireless manner;

Step 4: The meter reading system intermittently detects the power line channel status, and judges the current power line channel status according to the received communication signal of the meter reading. If the power line communication is normal, return to step 1. If the power line communication is abnormal, go to step 3. In this step, the criteria for judging the communication situation are: when the signal-to-noise ratio in the communication channel is less than a predetermined threshold or the packet loss rate when the meter reading system receives the signal is higher than 5%, it is considered to be abnormal communication, and the intermittent time is configurable Time, the default value is 30 minutes.

The communication signal includes a signal-to-noise ratio and a packet loss rate in the communication channel.

When the power line can communicate normally, the meter reading system receives the meter reading signal through the power line, and the control unit of the meter reading system periodically detects the power line communication status in the last 5 minutes. When the signal-to-noise ratio in the power line communication channel is lower than the predetermined threshold Or when the packet loss rate of the meter signal received by the meter reading system is higher than 20%, the control unit judges that the current power line environment has deteriorated through data calculation and logic detection. At this time, the meter reading system will be under the control of the control unit. , automatically switch to wireless meter reading communication. After the meter reading system switches to the wireless communication mode, the control unit automatically detects the current power line communication situation every 30 minutes. When it detects that the signal-to-noise ratio in the current power line communication channel is higher than the predetermined threshold or the control unit determines the current packet loss rate When it is lower than 5%, it is considered that the current power line environment has returned to a good state. At this time, the meter reading system will automatically switch from wireless communication to power line broadband communication under the control of the control unit.

This meter reading method can automatically detect the communication situation of the current system, independently select the appropriate data transmission method according to the current communication situation, expand the control range, and combine different transmission networks with the same system for the same detection and control. The synergy between systems ensures efficient and reliable work.

The above is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the description of the present invention and the contents of the accompanying drawings, or directly or indirectly used in other related technologies fields, all of which are equally included in the scope of patent protection of the present invention.

Claims (6)

1. a kilowatt meter reading-out system, is characterized in that: comprise power wire broadband carrier communication unit, wireless communication unit, clock unit, control module and storage unit;

Described power wire broadband carrier communication unit, wireless communication unit, clock unit and storage unit are all connected with control module;

Described power wire broadband carrier communication unit is for receiving and dispatching the signal of checking meter transmitting by broadband power line carrier mode;

Described wireless communication unit is for receiving and dispatching the signal of checking meter transmitting by communication;

Control module is for the detecting of power line channel situation, channel according to detecting output control kilowatt meter reading-out system between broadband power carrier communication and radio communication automatically switches, after switching channels, carry out automatic network-building, and by from power wire broadband carrier communication unit and the signal of checking meter that receives of wireless communication unit carry out format conversion and generate ammeter data;

Described clock unit provides clock trigger signal for control module;

Storage unit is used for the ammeter data of storage control unit, the control command that store electricity power line bandwidth carrier communication unit and wireless communication unit channel switch, the control parameter of store electricity line of force channel conditions detecting;

Described control module comprises data computing unit, logic judgment unit and buffer unit;

Described data computing unit is for carrying out Real-Time Monitoring to power line channel situation, and to checking meter, signal carries out format conversion;

Described logic judgment unit is for the judgement of power line channel situation, and the network channel of managing power line carrier wave and radio communication switches;

Described buffer unit is for the control parameter of control module and the buffer-stored of data;

In the process of work, in the normal situation of power line communication, kilowatt meter reading-out system communicates by broadband power line carrier unit and ammeter, when power line communication is abnormal, power wire broadband carrier communication unit and wireless communication unit send control signal by data bus to control module, control module receives after control signal, by data computing unit and logic judgment unit, judge whether to switch communication mode, when signal intelligence meets after the condition of switching communication mode, control module switches communication mode, by wireless communication unit and ammeter, carry out radio communication, and re-start networking, after communicating by letter by communication, control module still carries out detecting real-time to the channel conditions of line of electric force.

2. kilowatt meter reading-out system according to claim 1, is characterized in that: described storage unit comprises RAM and FLASH;

Described RAM is for working procedure and storage running data;

Described FLASH is for the control parameter of storage program, meter reading data and control module.

3. kilowatt meter reading-out system according to claim 1, is characterized in that: described clock unit is RTC clock unit.

4. a meter register method that is applied to the kilowatt meter reading-out system described in claim 1-3 any one, is characterized in that, comprises the following steps:

Step 1: receive and dispatch the signal of communication of checking meter by power wire broadband carrier communication; Described signal of communication comprises signal to noise ratio (S/N ratio) and the packet loss of communication channel;

Step 2: periodically detect power line channel situation, according to the signal of communication of the checking meter judgement current power line channel conditions receiving, if power line communication is normal, circulation step 2, if power line communication is improper, go to step 3, wherein, this communication conditions criterion is: when the packet loss when signal to noise ratio (S/N ratio) of power line communication channel receives signal lower than predetermined lowest threshold or kilowatt meter reading-out system is greater than 20%, think improper communication;

Step 3: carry out channel automatic switchover between power wire broadband carrier communication and radio communication, receive and dispatch the signal of communication of checking meter by communication;

Step 4: the intermittent power line channel situation that detects of kilowatt meter reading-out system, according to the signal of communication of the checking meter judgement current power line channel conditions receiving, if power line communication is normal, return to step 1, if power line communication is improper, circulation step 4, and wherein, this signal intelligence criterion is: when packet loss when radio communication channel signal to noise ratio (S/N ratio) is greater than predetermined high threshold or kilowatt meter reading-out system and receives signal is greater than 5%, think improper communication.

5. meter register method according to claim 4, is characterized in that: in step 2, the described cycle is 5 minutes.

6. meter register method according to claim 4, is characterized in that: in step 4, the described quiescent interval is 30 minutes.