阅读说明：本技术 一种基于可见光通信的配电系统末端拓扑结构识别系统及方法 (Power distribution system tail end topological structure recognition system and method based on visible light communication ) 是由 徐通通 陈浩 于 2020-06-17 设计创作，主要内容包括：本发明涉及一种基于可见光通信的配电系统末端拓扑结构识别系统及方法,包括系统主控、智能电表和智能断路器；主控包括MCU处理模块、LED光发射和接收装置及数据发送模块；智能电表包括MCU处理模块及LED光发射和接收装置；智能断路器包括MCU处理模块及LED光发射和接收装置；电表接收光信号并转化为电信号,识别出主控的寻址请求,向主控发送唯一地址码建立一级拓扑结构。智能断路器对距离最近的电表唯一地址码加值01,并向主控发送它的唯一地址码,主控根据智能断路器的唯一地址码建立二级拓扑结构。本发明基于可见光的定位更加精准,能够满足配电箱密闭空间内拓扑结构识别的要求,精确地识别出配电箱内的拓扑结构。(The invention relates to a visible light communication-based power distribution system tail end topological structure recognition system and method, which comprises a system main control unit, an intelligent ammeter and an intelligent circuit breaker; the main control module comprises an MCU processing module, an LED light emitting and receiving device and a data sending module; the intelligent electric meter comprises an MCU processing module and an LED light emitting and receiving device; the intelligent circuit breaker comprises an MCU processing module and an LED light emitting and receiving device; the ammeter receives the optical signal and converts the optical signal into an electric signal, identifies an addressing request of the master control, and sends a unique address code to the master control to establish a primary topological structure. The intelligent circuit breaker adds value 01 to the nearest unique address code of the ammeter, sends the unique address code to the master control, and the master control establishes a secondary topological structure according to the unique address code of the intelligent circuit breaker. The positioning method based on visible light is more accurate, can meet the requirement of identifying the topological structure in the closed space of the distribution box, and accurately identifies the topological structure in the distribution box.)

1. A visible light communication-based power distribution system tail end topological structure recognition system is characterized by comprising a system main control, N intelligent electric meters and N intelligent circuit breakers which are connected through a bus structure, wherein N is a natural number;

the system main control comprises an MCU processing module, an LED light emitting and receiving device and a data sending module; the intelligent electric meter comprises an MCU processing module and an LED light emitting and receiving device; the intelligent circuit breaker comprises an MCU processing module and an LED light emitting and receiving device;

the MCU processing module is responsible for data interaction between the system main control and the intelligent circuit breaker and the intelligent ammeter and controlling the running state of the intelligent circuit breaker;

the LED light emitting device comprises a signal input module, a modulation driving circuit and an LED light source array; the LED light receiving device comprises a photodiode array, a demodulation decoding circuit and a signal output module;

and the data sending module is responsible for sending data to the outside by the system master control and carrying out data transmission.

2. A power distribution system terminal topological structure identification method based on visible light communication is based on the identification system of claim 1, and is characterized in that the identification method comprises the following steps:

1) the system master control sends addressing requests to all the intelligent electric meters and the intelligent circuit breakers, the request signals are modulated into OFDM signals through a modulation driving circuit and input to an LED light source array, and the LED light source array sends optical signals containing request information outwards under the control of the driving signals;

2) the method comprises the following steps that a photodiode array of the intelligent ammeter receives optical signals sent by an LED light source array, the optical signals are converted into electric signals and sent to a demodulation decoding circuit, and the demodulation decoding circuit decodes the original addressing signals;

3) the N intelligent electric meters send unique address codes to the master control;

4) the master control receives the unique address codes of the intelligent electric meters, the N intelligent electric meters obtain the N unique address codes, the distance from each intelligent electric meter to the master control is identified, and the primary topology is established according to the distance;

5) the photodiode arrays of the N intelligent circuit breakers receive optical signals sent by the LED light source array, convert the optical signals into electric signals and send the electric signals to the demodulation and decoding circuit, the demodulation and decoding circuit decodes the original addressing signals, and at the moment, the intelligent circuit breakers enter a state of waiting for receiving a unique addressing code sent by the intelligent ammeter;

6) each intelligent circuit breaker receives the unique address codes sent by the N intelligent electric meters at the same time, identifies the intelligent electric meter closest to the intelligent circuit breaker, adds 2-bit data after the unique address code, and generates the unique address code of the intelligent circuit breaker, wherein the value of the data is 01;

7) the N intelligent circuit breakers send own unique address codes to the master control;

8) the master control receives the unique address codes of the N intelligent circuit breakers, and establishes a secondary topological structure according to the similarity relation between the unique address codes of the intelligent circuit breakers and the unique address codes of the intelligent electric meter.

3. The visible light communication-based power distribution system terminal topology identification method according to claim 2, wherein in the step 3), the unique address code means that each smart meter has a separate and unique address data, and the address is preset by a constructor.

4. The visible light communication-based power distribution system terminal topology structure identification method according to claim 2, wherein the same method is adopted for identifying the distance from each intelligent electric meter to the master control by the master control and identifying the distance from each intelligent electric meter to the intelligent circuit breaker by the intelligent circuit breaker, and the method comprises the following steps:

the transmitting end transmits an optical signal, and the receiving end receives the optical signal; the transmitting end is point S, the receiving end is point A, point O is the projection point of point S on the horizontal plane where point A is located, and the light intensity of the optical signal received by the receiving end is as follows:

h (r, theta) is signal light intensity, d is the vertical distance from the point S to the point O, r is the distance from the point A to the point O, and A is the receiving area of the receiving end; t is_s(θ) is detector optical filter gain; g (theta) is the light gathering gain of the detector; m is called a light source radiation mode and is a parameter for representing the light emitting directivity; theta_1/2Is the half-power angle of the light source, i.e. the angle between the beam with half the maximum intensity and n, theta being the angle between the light source and the illuminated surface_1/2A constant value is given, where H (R, θ) can be measured by a photodiode, d is a fixed value, so that R ═ d · tan θ can be calculated from a trigonometric function relationship, and R ═ R · sin θ is a spatial distance from the receiving end to the transmitting end.

5. The visible light communication-based power distribution system tail end topological structure recognition method as claimed in claim 2, wherein the master control calculates a distance R from each intelligent electric meter to the master control₁₁-R_1nTo R, to R₁₁-R_1nArranged from small to large and accordingly a one-level topology is established.

6. The visible light communication-based power distribution system terminal topology identification method as claimed in claim 2, wherein the smart circuit breaker identifies a distance R from each smart meter to the smart circuit breaker₂₁-R_2nTo R, to R₂₁-R_2nAnd arranging the intelligent electric meters from small to large, wherein the intelligent electric meter with the minimum distance is the intelligent electric meter closest to the intelligent circuit breaker, and establishing a two-stage topology according to the relative spatial position relationship between the intelligent circuit breaker and the intelligent electric meter.

7. The visible light communication-based power distribution system terminal topology identification method of claim 2, wherein the identification method further comprises step 9): after the topological structure of the distribution box is established, the master control sends the topological graph to an upstream server to complete the topological structure of the whole distribution network; when the intelligent electric meter and the intelligent circuit breaker are replaced or maintained, the topological structure of the distribution box can be automatically identified by restarting the system.

8. The visible light communication-based power distribution system terminal topology structure identification method according to claim 2, wherein the master control performs data interaction with the smart meter and the smart breaker, and a data frame format of each data transmission comprises: start sequence, address data, information data bits, check bytes, and end sequence.

Technical Field

The invention relates to a visible light communication-based power distribution system tail end topological structure identification system and method, and belongs to the technical field of electric power detection.

Background

The topological structure at the tail end of the power distribution system refers to the incidence relation between the circuit breakers and the electric meters of each household in a distribution box (or a distribution cabinet) after a power grid in the power distribution system enters a household. The current topological structure research is concentrated on the direction of a power grid topological structure of a high-low voltage transformer area, the tail end of a common node is positioned in a power distribution meter box (or a power distribution meter cabinet), and the topological structure of a power distribution system after the power grid enters the home is not researched. This is because the accuracy of the existing topology identification method cannot meet the requirement of being accurate to the inside of the distribution box (or distribution cabinet). When a distribution network fails, the requirements of accurate fault positioning, safety guarantee, timely power supply recovery and the like are often difficult to meet.

The methods commonly used for identifying the topological structure of the power distribution network at present mainly comprise the following methods:

1. the topology is established using the mobile device. Namely, the tester carries out on-site investigation, and artificially judges and records the circuit topological relation. This method is labor and time intensive, inefficient and prone to error.

2. A method based on big data analysis. Namely, the electric meter data in a certain range of the platform area is calculated, and the topological structure is judged according to the similarity. The method has extremely large calculation amount and is easy to cause network blockage.

3. A method based on characteristic current. The method is characterized in that characteristic current is injected into one power supply branch of the power distribution network, and topology is identified by detecting the characteristic current of other branches.

For example, chinese patent document CN203911593U discloses a power grid topology recognition device and a power grid topology recognition system, where the power grid topology recognition device includes: the first switching device is arranged on a first power supply line and used for controlling the connection or disconnection of the first power supply line; the second switching equipment is arranged on a second power supply line and used for controlling the connection or disconnection of the second power supply line; a third switching device for connecting between the first power supply line and the second power supply line; and the signal receiver is respectively connected with the first power supply line and the second power supply line and used for identifying the states of the first switching device, the second switching device and the third switching device according to power frequency communication signals of the first power supply line and the second power supply line. Through the utility model discloses, the effect of the topological structure in the timely definite distribution network has been reached. Chinese patent document CN210404847U discloses a power distribution network power consumption information acquisition and distribution structure topology identification system, which mainly includes a carrier data collection terminal, a branch monitoring terminal, a wireless collection module and a wireless carrier collection unit, and in the transformer box: mounting the carrier data collection terminal on the A, B, C three power supply lines; a circuit breaker is arranged below the carrier data collection terminal; the branch monitoring terminal is arranged below the circuit breaker and is in wireless communication with the wireless acquisition module, and the wireless acquisition module and the carrier data collection terminal are connected with a power distribution acquisition system; in the block terminal: and the A, B, C three live wires are respectively provided with the wireless carrier aggregation units. The branch monitoring terminal can monitor the voltage, the current and the temperature of the circuit breaker in real time, so that the occurrence of dangerous hidden dangers is reduced; the wireless carrier aggregation unit has a carrier relay function, and can avoid the situations of signal attenuation, transmission information loss and information ambiguity. Chinese patent document CN110932396A discloses a low-voltage distribution network topology identification system based on pulse characteristic current signals, wherein a bus current centralized controller is installed on a low-voltage incoming line switch layer; the low-voltage outlet switch layer is provided with a plurality of branch current detectors, the branch switch layer is provided with a plurality of branch current detectors, the user switch layer of the metering box is provided with a plurality of branch current detectors, and the tail end of a user is provided with a pulse characteristic current generator; on the basis of not changing the original circuit, the bus current integrated controller is installed at the master switch, and the branch current detectors and the pulse characteristic current generators are respectively installed at the tail ends of all the branches and the power distribution network users, so that the low-voltage power distribution network topological structure is obtained, the change of the power distribution network topological structure can be monitored in real time on line, the real-time monitoring and reporting of the low-voltage power distribution network topological structure are realized, and the improvement of the power supply reliability and the power grid operation and maintenance management level is facilitated.

Visible light communication is a new generation of wireless communication means, which represents 1 and 0 in binary code by the on and off of LED. Theoretically, the communication rate of visible light communication can reach hundreds of million per second, the wireless communication device does not occupy radio frequency spectrum, does not generate electromagnetic radiation, is extremely good in safety, can be applied to an electromagnetic sensitive area, and is very suitable for application scenes under the Internet of things.

The visible light communication is used for identifying the tail end topological structure of the power distribution system, and the method is a brand-new research direction and has important significance for improving the overall operation and maintenance control capability of a power grid and improving the power supply stability.

In the existing intelligent power distribution solution, the communication between the intelligent circuit breaker and the system is usually completed in wired and wireless modes such as an RS485 bus, NB-IoT, WiFi and the like, and the problems that signals are easily interfered, information is easily lost and the like exist in the transmission process. The visible light communication provides a brand new thought for system communication by high communication rate, high reliability and strong anti-interference capability, belongs to the blank research field at present, and has great significance.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a power distribution system tail end topological structure identification system and method based on visible light communication.

The technical scheme of the invention is as follows:

a visible light communication-based power distribution system tail end topological structure recognition system comprises a system main control, N intelligent electric meters and N intelligent circuit breakers which are connected through a bus structure, wherein N is a natural number;

the system main control comprises an MCU processing module, an LED light emitting and receiving device and a data sending module; the intelligent electric meter comprises an MCU processing module and an LED light emitting and receiving device; the intelligent circuit breaker comprises an MCU processing module and an LED light emitting and receiving device;

the MCU processing module is responsible for data interaction between the system main control and the intelligent circuit breaker and the intelligent ammeter and controlling the running state of the intelligent circuit breaker;

the LED light emitting device comprises a signal input module, a modulation driving circuit and an LED light source array; the LED light receiving device comprises a photodiode array, a demodulation decoding circuit and a signal output module;

and the data sending module is responsible for sending data to the outside by the system master control and carrying out data transmission.

A power distribution system tail end topological structure identification method based on visible light communication is based on the identification system and comprises the following steps:

1) the system master control sends addressing requests to all the intelligent electric meters and the intelligent circuit breakers, the request signals are modulated into OFDM signals through a modulation driving circuit and input to an LED light source array, and the LED light source array sends optical signals containing request information outwards under the control of the driving signals;

2) the method comprises the following steps that a photodiode array of the intelligent ammeter receives optical signals sent by an LED light source array, the optical signals are converted into electric signals and sent to a demodulation decoding circuit, and the demodulation decoding circuit decodes the original addressing signals;

3) the N intelligent electric meters send unique address codes to the master control;

4) the master control receives the unique address codes of the intelligent electric meters, the N intelligent electric meters obtain the N unique address codes, the distance from each intelligent electric meter to the master control is identified, and the primary topology is established according to the distance;

5) the photodiode arrays of the N intelligent circuit breakers receive optical signals sent by the LED light source array, convert the optical signals into electric signals and send the electric signals to the demodulation and decoding circuit, the demodulation and decoding circuit decodes the original addressing signals, and at the moment, the intelligent circuit breakers enter a state of waiting for receiving a unique addressing code sent by the intelligent ammeter;

6) each intelligent circuit breaker receives the unique address codes sent by the N intelligent electric meters at the same time, identifies the intelligent electric meter closest to the intelligent circuit breaker, adds 2-bit data after the unique address code, and generates the unique address code of the intelligent circuit breaker, wherein the value of the data is 01;

7) the N intelligent circuit breakers send own unique address codes to the master control;

8) the master control receives the unique address codes of the N intelligent circuit breakers, and establishes a secondary topological structure according to the similarity relation between the unique address codes of the intelligent circuit breakers and the unique address codes of the intelligent electric meter.

Preferably, in step 3), the unique address code indicates that each smart meter has a separate and unique address data, and the address is preset by the constructor.

Preferably, the same method is adopted for identifying the distance from each intelligent electric meter to the master control by the master control and identifying the distance from each intelligent electric meter to each intelligent circuit breaker by the intelligent circuit breaker, and the method comprises the following steps:

the transmitting end transmits an optical signal, and the receiving end receives the optical signal; the transmitting end is point S, the receiving end is point A, point O is the projection point of point S on the horizontal plane where point A is located, and the light intensity of the optical signal received by the receiving end is as follows:

h (r, theta) is signal light intensity, d is the vertical distance from the point S to the point O, r is the distance from the point A to the point O, and A is the receiving area of the receiving end; t is_s(θ) is detector optical filter gain; g (theta) is the light gathering gain of the detector; m is called a light source radiation mode and is a parameter for representing the light emitting directivity; theta_1/2Is the half-power angle of the light source, i.e. the angle between the beam with half the maximum intensity and n, theta being the angle between the light source and the illuminated surface_1/2A constant value is given, where H (R, θ) can be measured by a photodiode, d is a fixed value, so that R ═ d · tan θ can be calculated from a trigonometric function relationship, and R ═ R · sin θ is a spatial distance from the receiving end to the transmitting end.

Preferably, the master control calculates the distance R from each intelligent electric meter to the master control₁₁-R_1nTo R, to R₁₁-R_1nArranged from small to large and accordingly a one-level topology is established.

Preferably, the intelligent circuit breaker identifies the distance R from each intelligent electric meter to the intelligent circuit breaker₂₁-R_2nTo R, to R₂₁-R_2nThe intelligent circuit breakers are arranged from small to large, and the intelligent circuit breaker closest to the intelligent circuit breaker with the minimum distance is the intelligent circuit breaker closest to the intelligent circuit breakerAnd the electric meter establishes a two-stage topology according to the relative spatial position relationship between the intelligent circuit breaker and the intelligent electric meter.

Preferably, the identification method further comprises step 9): after the topological structure of the distribution box is established, the master control sends the topological graph to an upstream server to complete the topological structure of the whole distribution network; when the intelligent electric meter and the intelligent circuit breaker are replaced or maintained, the topological structure of the distribution box can be automatically identified by restarting the system.

Preferably, the master control performs data interaction with the smart meter and the smart breaker, and the data frame format for sending data each time includes: start sequence, address data, information data bits, check bytes, and end sequence.

The invention has the beneficial effects that:

1. the method can identify the topological structure of the tail end of the power distribution system, effectively overcomes the defects of the conventional topological identification method, improves the accuracy of the overall topological structure of the power grid, improves the accuracy of fault location, and reduces the maintenance cost of the power grid.

2. The positioning based on visible light is more accurate, the requirement of identifying the topological structure in the closed space of the distribution box can be met, and the topological structure in the distribution box or the distribution box can be accurately identified.

3. The invention adopts visible light, has high communication speed of the visible light, does not occupy radio frequency spectrum, does not generate electromagnetic radiation, has excellent safety and is an excellent choice for replacing the prior communication mode.

Drawings

Fig. 1 is a topological structure diagram of a distribution box at the end of a power distribution system in a typical application scenario.

Fig. 2 is a block diagram of a signal transmitting and receiving module for visible light communication.

Fig. 3 is a flow chart for identifying a power distribution system terminal topology.

Fig. 4 is a data frame format when the intelligent circuit breaker is in communication with the system.

Fig. 5 is a topological structure diagram of a nine-epitope electric box.

Fig. 6 is a diagram of a visible light positioning model.

Detailed Description

The present invention will be further described by way of examples, but not limited thereto, with reference to the accompanying drawings.