Distribution network automation equipment feeder terminal device

Abstract

The utility model discloses a feeder terminal device for distribution network automation equipment. The feeder terminal device comprises an analog quantity acquisition unit, a telecommand quantity acquisition unit, a microcontroller unit and a communication unit, the analog quantity input end of the microcontroller unit is electrically connected with the output end of the analog quantity acquisition unit, and the digital quantity input end of the microcontroller unit is electrically connected with the output end of the telecommand quantity acquisition unit; the communication unit is electrically connected to the communication end of the microcontroller unit. The analog quantity acquisition unit performs filtering operation processing when performing analog signal acquisition, so that the sampling precision and the anti-interference capability are improved, the remote signaling quantity acquisition unit uses photoelectric isolation and rapid response to acquire voltage and current of an opening and closing loop when a switch acts and analyze the action characteristics of the switch, and then the remote signaling quantity acquisition unit is combined with the communication unit, so that the communication efficiency is improved. And wired and wireless communication transmission is performed, so that the transmission rate is further improved while stable output is ensured, and the fault processing response is quicker.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of power system distribution automation, especially relates to a distribution network automation equipment feeder terminal device. BACKGROUND

[0002] In modern power system, distribution network as the last link of power transmission, its stability and reliability directly affect the safety and economy of the whole power supply system. The main function of distribution network automation equipment is to isolate faults and quickly restore power supply, aiming at improving the reliability and quality of power supply.

[0003] The existing feeder terminal device integrates various electrical elements in the terminal machine, and detects the power grid through the circuit connection and cooperation of various electrical elements, but the existing feeder terminal does not process the signal without filtering when receiving analog signal, so that the device will be affected by electromagnetic interference and environmental noise in the use process, resulting in inaccurate sampling data, and the existing technology relies on single wired transmission mode when transmitting signal, so that the signal transmission has delay, and then the disconnection isolation of the fault part will be delayed. In view of this, the present scheme provides a distribution network automation equipment feeder terminal device to solve the above problems. UTILITY MODEL CONTENT

[0004] The utility model aims at providing a distribution network automation equipment feeder terminal device to solve the problems in the above background technology.

[0005] To achieve the above purpose, the utility model provides the following technical scheme: a distribution network automation equipment feeder terminal device, comprising:

[0006] Analog quantity acquisition unit, the analog quantity acquisition unit is used for collecting voltage and current analog signal;

[0007] Remote signal acquisition unit, the remote signal acquisition unit is used for collecting switch quantity;

[0008] Microcontroller unit, the analog quantity input end of the microcontroller unit is electrically connected with the output end of the analog quantity acquisition unit, and the digital quantity input end of the microcontroller unit is electrically connected with the output end of the remote signal acquisition unit;

[0009] Communication unit, the communication unit is electrically connected to the communication end of the microcontroller unit, and the communication unit is used for the communication connection of the microcontroller unit and the main station.

[0010] Preferably, the analog quantity acquisition unit comprises:

[0011] Mutual inductor module, the mutual inductor module comprises current transformer and voltage transformer, the current transformer is used for low-frequency conversion of current, and the voltage transformer is used for low-voltage conversion of voltage;

[0012] An analog-to-digital converter, an input end of the analog-to-digital converter is electrically connected with an output end of the transformer module, and an output end of the analog-to-digital converter is electrically connected with an analog input end of the microcontroller unit.

[0013] Preferably, an analog low-pass filter is electrically connected between the output end of the transformer module and the input end of the analog-to-digital converter, and a band-stop filter is arranged between the output end of the analog-to-digital converter and the analog input end of the microcontroller unit.

[0014] Preferably, the remote signaling acquisition unit comprises:

[0015] A switching device, the switching device is used for acquiring a switching signal;

[0016] An optoelectronic isolator, an input end of the optoelectronic isolator is electrically connected with an output end of the switching device, and an output end of the optoelectronic isolator is electrically connected with a digital input end of the microcontroller unit, and the optoelectronic isolator is used for converting the switching signal into an electrical signal.

[0017] Preferably, a control output unit is arranged at the output end of the microcontroller unit, and the control output unit is used for fault isolation through switching on and off.

[0018] Preferably, the communication unit comprises:

[0019] An optical fiber, the optical fiber is used for wired communication between the microcontroller unit and a master station;

[0020] A 5G communication module, the 5G communication module is used for wireless communication between the microcontroller unit and the master station.

[0021] Technical effects and advantages of the utility model:

[0022] The utility model discloses an analog quantity acquisition unit, remote signaling acquisition unit, microcontroller unit and communication unit are integrated in one terminal equipment, wherein, when carrying out analog signal acquisition, the analog quantity acquisition unit carries out filter operation processing, improves sampling precision and anti-interference ability, and the remote signaling acquisition unit uses photoelectric isolation, and the switching on and off loop voltage and current when switching action are collected quickly, switching action characteristics are analyzed, then wired communication transmission is carried out in combination with the communication unit, output stability is guaranteed, transmission rate is further improved, and fault processing response is more rapid. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is circuit control connection schematic diagram of the utility model device.

[0024] In the figure: 1, analog quantity acquisition unit; 101, mutual inductor module; 102, analog low-pass filter; 103, analog-to-digital converter; 104, band-stop filter; 2, remote signaling quantity acquisition unit; 201, switch device; 202, optoelectronic isolator; 3, microcontroller unit; 4, control output unit; 5, communication unit; 501, optical fiber; 502, 5G communication module. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.

[0026] The utility model provides a kind of distribution network automation equipment feeder terminal device as shown in Figure 1 As shown in the figure, it comprises:

[0027] Analog quantity acquisition unit 1, analog quantity acquisition unit 1 is used for the collection of voltage and current analog signal, then through digital filtering and Fourier calculation, the effective value is obtained;

[0028] It should be noted that the calculation method of effective value adopts frequency domain calculation method, including the following steps:

[0029] First, windowing is added to sampling data and fast Fourier transform is carried out, and the amplitude of each frequency component is extracted, and is recorded as A k；

[0030] Second step, the effective value of each component is calculated, and is expressed as:

[0031]

[0032] Among them, A k Indicates the amplitude of the kth frequency component in frequency domain;

[0033] Third step, the total effective value is calculated, and is expressed as:

[0034]

[0035] Among them, V rms Indicates the square root of the square sum of all frequency component effective values, and N indicates the total number of sampling points.

[0036] Specifically, analog quantity acquisition unit 1 comprises:

[0037] The transformer module 101 includes a current transformer for low-frequency conversion of current and a voltage transformer for low-voltage conversion of voltage.

[0038] It should be noted that the function of the current transformer is to convert high current (main current in the power system) into low current for measurement and relay protection, and its working principle is based on the law of electromagnetic induction. The current transformer converts the primary side current (main current) into the secondary side current (1A or 5A) through induction, thereby realizing safe and accurate current measurement.

[0039] The function of the voltage transformer is to convert high voltage (main voltage in the power system) into low voltage for measurement and relay protection. The working principle of the voltage transformer is also based on the law of electromagnetic induction. The voltage transformer converts the primary side voltage (main voltage) into the secondary side voltage (100V or 110V) through induction, thereby realizing safe and accurate voltage measurement.

[0040] The input end of the analog-to-digital converter 103 is electrically connected to the output end of the transformer module 101.

[0041] It should be noted that the analog-to-digital converter 103 converts continuous analog signals (voltage or current) into discrete digital signals for processing by a microcontroller (MCU) or a digital signal processor (DSP). The working principle of the analog-to-digital converter 103 mainly includes the following steps:

[0042] A1, sampling, the analog-to-digital converter 103 samples the input analog signal at a certain sampling rate, wherein the sampling rate satisfies the Nyquist theorem, i.e. the sampling frequency should be at least twice the highest frequency of the signal to avoid aliasing;

[0043] A2, quantization, the sampled analog signal is quantized into discrete values, and the quantization accuracy depends on the resolution of the ADC. Common resolutions include 8-bit, 10-bit, 12-bit, and 16-bit. The present scheme uses a 16-bit analog-to-digital converter 103, and the higher the resolution, the closer the quantized digital signal is to the original analog signal;

[0044] A3, encoding, the quantized discrete values are converted into binary numbers for easy processing in a digital system.

[0045] The remote signaling quantity acquisition unit 2 is used to acquire switch quantities.

[0046] Specifically, the remote signaling quantity acquisition unit 2 includes:

[0047] The switch device 201 is used to acquire switch quantity signals.

[0048] The photoelectric isolator 202 is electrically connected with the output end of the switch device 201, and is used for converting the switch signal into an electric signal.

[0049] It should be noted that the photoelectric isolator 202 converts the input switch signal (on / off state of the switch) into an optical signal, and then converts the optical signal into an electric signal by the light-sensitive element (photodiode or phototransistor) at the receiving end. The switch signal is a binary signal, indicating the on (1) or off (0) state. The microcontroller unit 3 receives the signals through the digital input port. The switch signal is from the switch device 201. The digital input port of the microcontroller unit 3 monitors the signals in real time. Since the mechanical switch may produce jitter (i.e. multiple switching in a short time) when switching state, the de-bouncing process is needed to ensure that the collected signal is stable. The de-bouncing method includes time delay method, which waits for a certain time (such as 10-50 milliseconds) after the state changes, and then reads the signal. If the state does not change within this time, it is considered that the state is valid. The state counting method counts the state changes. Only when the state is consistent in several consecutive readings, it is considered that the state is valid.

[0050] The microcontroller unit 3 is electrically connected with the output end of the analog quantity acquisition unit 1 through the analog quantity input end, and is electrically connected with the output end of the remote signaling quantity acquisition unit 2 through the digital quantity input end.

[0051] Specifically, the output end of the analog-to-digital converter 103 is electrically connected with the analog quantity input end of the microcontroller unit 3, and the output end of the photoelectric isolator 202 is electrically connected with the digital quantity input end of the microcontroller unit 3.

[0052] Further, the output end of the mutual inductor module 101 is electrically connected with the input end of the analog-to-digital converter 103 through the analog low-pass filter 102, and the output end of the analog-to-digital converter 103 is provided with the band-stop filter 104.

[0053] It should be noted that the analog low-pass filter 102 is added in front of the analog-to-digital converter 103, and the cut-off frequency is higher than the target highest frequency. Then the band-stop filter 104 is added behind the analog-to-digital converter 103 to eliminate high-frequency noise and power frequency interference.

[0054] Further, the output end of the microcontroller unit 3 is provided with the control output unit 4, which is used for fault isolation through switching on and off.

[0055] It should be noted that the control output unit 4 uses the switching on and off control to isolate the fault according to the section where the fault occurs, and at the same time restores the power supply of the non-fault section, and uploads the related signals to the master station.

[0056] The communication unit 5 is electrically connected to the communication end of the microcontroller unit 3, and is used for the communication connection between the microcontroller unit 3 and the master station.

[0057] Specifically, the communication unit 5 comprises:

[0058] The optical fiber 501 is used for the wired communication between the microcontroller unit 3 and the master station.

[0059] The 5G communication module 502 is used for the wireless communication between the microcontroller unit 3 and the master station.

[0060] It should be noted that the microcontroller unit 3 uses the 5G communication module 502 or the optical fiber 501 to communicate, so as to interact with the master station, including receiving various commands of the master station and uploading telemetry and telecontrol;

[0061] In the design of the present scheme, the mutual inductor module 101 is connected in the power grid circuit to be detected, the analog low-pass filter 102, the analog-to-digital converter 103, the band-stop filter 104, the optoelectronic isolator 202 and the microcontroller unit 3 are integrated in a terminal device, the optical fiber 501 and the 5G communication module 502 are integrated in the communication end of the microcontroller unit 3, then the mutual inductor module 101 is connected to the input end of the analog low-pass filter 102 through the conduction circuit, the switch device 201 of the detected power grid circuit is connected to the input end of the optoelectronic isolator 202, and the control output unit 4 is carried on the output end of the microcontroller unit 3 to perform the on-off output control, so as to form a set of detection, communication and feedback output feeder terminal.

[0062] Finally, it should be noted that the above only describes the preferred embodiments of the present application, and is not used to limit the present application, although the present application has been described in detail with reference to the foregoing embodiments, for those skilled in the art, the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced, any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A distribution automation device feeder terminal apparatus, characterized by, The utility model relates to a kind of intelligent terminal for power supply, including: Analog acquisition unit (1), the analog acquisition unit (1) is used for the acquisition of voltage and current analog signal; Remote signaling acquisition unit (2), the remote signaling acquisition unit (2) is used for acquisition switch quantity; Microcontroller unit (3), the analog input end of the microcontroller unit (3) is electrically connected with the output end of analog acquisition unit (1), and the digital quantity input end of the microcontroller unit (3) is electrically connected with the output end of remote signaling acquisition unit (2); Communication unit (5), the communication unit (5) is electrically connected to the communication end of microcontroller unit (3), and the communication unit (5) is used for microcontroller unit (3) and main station communication connection.

2. The distribution automation device feeder terminal of claim 1, wherein, The analog acquisition unit (1) includes: Transformer module (101), the transformer module (101) includes current transformer and voltage transformer, the current transformer is used for low frequency conversion of current, and the voltage transformer is used for low voltage conversion of voltage; Analog-digital converter (103), the input end of the analog-digital converter (103) is electrically connected with the output end of transformer module (101), and the output end of the analog-digital converter (103) is electrically connected with the analog input end of microcontroller unit (3).

3. The distribution automation device feeder terminal of claim 2, wherein, Analog low-pass filter (102) is electrically connected between the output end of the transformer module (101) and the input end of the analog-digital converter (103), and band-stop filter (104) is arranged between the output end of the analog-digital converter (103) and the analog input end of microcontroller unit (3).

4. The distribution automation device feeder terminal of claim 1, wherein, The remote signaling acquisition unit (2) includes: Switching device (201), the switching device (201) is used for acquisition switch quantity signal; Optoelectronic isolator (202), the input end of the optoelectronic isolator (202) is electrically connected with the output end of switching device (201), and the output end of the optoelectronic isolator (202) is electrically connected with the digital quantity input end of microcontroller unit (3), and the optoelectronic isolator (202) is used for converting switch quantity signal into electric signal.

5. The distribution automation device feeder terminal of claim 1, wherein, The output end of the microcontroller unit (3) is provided with control output unit (4), and the control output unit (4) is used for fault isolation by switching on and off.

6. The distribution automation device feeder terminal of claim 1, wherein, The communication unit (5) includes: Optical fiber (501), the optical fiber (501) is used for wired communication of microcontroller unit (3) and main station; 5G communication module (502), the 5G communication module (502) is used for wireless communication of microcontroller unit (3) and main station.

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