CN201589855U - Relay protection tester detection device - Google Patents

Abstract

The utility model discloses a detection device for a relay protection tester. The detection device can not only realize the high-precision measurement (0.05 grade) of the AC and DC voltage and current parameters of the relay protection tester and the high-precision measurement of the AC voltage and current phase (0.05°), but also can realize the high-precision measurement of the relay protection tester In addition, it can also detect the total harmonic distortion rate, response speed and synchronization of the output amplitude of the AC voltage source and AC current source of the relay protection tester. It includes signal sampling circuit, A/D conversion circuit, DSP processor, color liquid crystal display, keyboard. The signal sampling circuit is connected with the A/D conversion circuit, and the A/D conversion circuit is connected with the DSP processor, responsible for signal sampling, processing and calculation, 8.4-inch TFT color LCD display and keyboard processing; the photoelectric isolation circuit is connected with the DSP processor, It is responsible for transmitting signals with light as the medium in the case of electrical isolation, and isolating the input and output circuits.

Description

Relay protection tester detection device

technical field

The utility model relates to a detection device for detecting a relay protection tester, in particular, it can detect the total output amplitude of the relay protection tester's AC and DC voltage, current, frequency, phase, time, and AC voltage source and AC current source. A relay protection tester detection device for harmonic distortion rate, response speed and synchronization.

Background technique

With the rapid development of my country's electric power industry, the capacity of generating units is getting larger and larger, the voltage level of the power grid is getting higher and higher, and the scale of power generation and transmission networks is getting larger and larger, which puts forward higher and higher requirements for safe production. Since the relay protection device is a very important part of the power grid, it is increasingly playing an inestimable role in protecting the safe and reliable operation of the power system. At present, the best detection method is to use a relay protection tester to detect it. Convenient and precise.

However, since the detection of the relay protection tester involves many professional fields such as relay protection, electrical measurement, and time measurement, it is difficult to completely detect the items of the relay protection tester. At present, the domestic calibration of relay protection testers mainly uses multiple high-precision multimeters to test the AC and DC voltage, current, frequency, and phase accuracy of relay protection testers. The steps are cumbersome and cannot detect the relay protection tester AC. The total harmonic distortion rate and response speed of the voltage source and the output amplitude of the AC current source, the synchronization between the AC current source and the AC voltage source, and the load capacity of the auxiliary DC power supply of the test device; Existing time verification equipment cannot detect the response speed and action time of most relay protection testers. At present, some use oscilloscopes for detection, and some use millisecond meters for detection, and the detection error is large, and the accuracy is difficult to guarantee. At present, there is no product in China that can not only detect the AC and DC voltage, current, frequency, phase, and time accuracy of the relay protection tester, but also accurately detect the above parameters.

Utility model content

The purpose of this utility model is to overcome the above-mentioned defects of the prior art and provide a detection device for a relay protection tester. The detection device can not only realize the high-precision measurement and AC High-precision measurement of voltage and current phase, and can realize the measurement of the action time of the relay protection tester. In addition, it can also measure the total harmonic distortion rate and response of the output amplitude of the AC voltage source and the AC current source of the relay protection tester. Check speed and synchronization.

The utility model is realized through the following schemes: including a signal sampling circuit, an A/D conversion circuit, a DSP processor, a photoelectric isolation circuit, a color liquid crystal display, a keyboard, the output of the signal sampling circuit is connected with the A/D conversion circuit, and the A/D conversion circuit Connected with DSP processor, it is responsible for signal sampling and processing; DSP processor, it is responsible for signal sampling, processing and calculation TFT color LCD display and keyboard processing; photoelectric isolation circuit is connected with DSP processor, it is responsible for electrical isolation In this case, the signal is transmitted through the medium of light, and the input and output circuits are isolated.

The signal sampling circuit described in the utility model includes a current transformer, a voltage transformer, a DC sampling circuit, three signal conditioning circuits and a dual-four-select-one analog switch. The A/D conversion circuit includes a 6-channel 16-bit A/D converter, the AC current and voltage output by the relay protection tester are connected to the current transformer and voltage transformer, and the DC current, voltage and DC output of the relay protection tester are connected to each other. The sampling circuit is connected, and then connected to the dual-four-choice analog switch through the corresponding signal conditioning circuit, so as to realize the sampling of AC and DC voltage and current and send them to the signal conditioning circuit and the dual-four-choose one analog switch for processing; The signal output by the switch is sent to the A/D converter for A/D conversion, the A/D converter is connected with the DSP processor, and the A/D conversion signal is sent to the I/O port data bus of the DSP processor.

The dual-four-select-one analog switch described in the utility model is ADG201, and the A/D converter is AD976. The DSP processor is a low-power DSP microprocessor TMS320F2812. The photoelectric isolation circuit is a high-speed optocoupler optocoupler 6N137.

The utility model has the following advantages:

1. The utility model overcomes the need to use a plurality of high-precision multimeters to test the AC and DC voltage, current, frequency, and phase accuracy of the relay protection tester in the prior art. The steps are cumbersome and the AC voltage source of the relay protection tester cannot be detected. The total harmonic distortion rate and response speed of the output amplitude of the AC current source, the synchronization between the AC current source and the AC voltage source, the load capacity, response speed and action time of the auxiliary DC power supply of the test device.

The utility model can not only realize the high-precision measurement (0.05 degree) of the AC and DC voltage and current parameters of the relay protection tester and the high-precision measurement (0.05°) of the AC voltage and current phase, but also realize the high-precision measurement of the relay protection tester In addition, it can also detect the total harmonic distortion rate, response speed and synchronization of the output amplitude of the AC voltage source and the AC current source of the relay protection tester. The technical indicators meet the requirements of DL/T624-1997 "Relay Protect the requirements of the technical conditions of the microcomputer test device.

2. The utility model adopts multi-chip high-speed A/D cyclic sampling technology to improve signal acquisition speed.

3. The utility model uses a photoelectric isolation circuit to isolate the input and output circuits, suppress system noise, eliminate ground loop interference, and improve response speed.

4. The utility model adopts DSP processor to be responsible for signal sampling, signal processing and calculation, etc., adopts 8.4-inch TFT color LCD display and keyboard processing, and has a Chinese character man-machine interface with clear writing and large amount of information, and is easy to use.

Description of drawings

Fig. 1 is the utility model embodiment circuit composition diagram;

Fig. 2 is the connection circuit diagram of the signal sampling circuit signal conditioning circuit and the double four selection one analog switch;

Fig. 3 is the connection diagram of A/D conversion circuit and DSP processor;

Fig. 4 is the connection diagram of DSP processor and photoelectric isolation circuit, liquid crystal display, keyboard;

Figure 5 is a photoelectric isolation circuit and its connection with the DSP processor.

Detailed ways

The utility model will be described in detail below in conjunction with the embodiments and with reference to the accompanying drawings.

Referring to accompanying drawing 1, present embodiment is made of signal sampling circuit, A/D conversion circuit, DSP processor (10), photoelectric isolator (13), color liquid crystal display (11) and keyboard (12). The signal sampling circuit includes a current transformer (1), a voltage transformer (2), a direct current sampling circuit (3), a signal conditioning circuit (4) (5) (6) and a dual four-selection one analog switch (7). The A/D conversion circuit is a 6-channel 16-bit A/D converter (8), (9). The AC current and voltage output by the relay protection tester are connected to the current transformer (1) and the voltage transformer (2), and the DC current and voltage output by the relay protection tester are connected to the DC sampling circuit (3), and then the signal The conditioning circuit (4), (5) and (6) are connected with the dual four-select one analog switch (7) to realize AC and DC voltage and current sampling and send them to the signal conditioning circuit and the dual four-select one analog switch (7) for processing. The signal output by double four selection one analog switch (7) is sent into A/D converter (8), (9) and carries out A/D conversion, A/D converter (8), (9) and DSP processor (10 ) is connected, and the A/D conversion signal is sent to the I/O port data bus of the DSP processor. The photoelectric isolation circuit (13) is connected with the DSP processor (10), and the binary input signal is sent to the I/O port of the DSP processor (10) for processing through the photoelectric isolation circuit (13). The light transmits signals for the coal medium, and isolates the input and output circuits; the I/O port of the DSP processor (10) is connected with the color liquid crystal display (11) and the keyboard (12), and is responsible for signal sampling, data processing and calculation, and displays and keyboard handling.

This implementation uses an 8.4-inch TFT color liquid crystal display, the DSP processor is a low-power DSP microprocessor (TMS320F2812), a dual four-selection analog switch ADG201, an A/D sampling chip AD976, and a photoelectric isolation circuit is a high-speed photocoupler (optical Coupling) 6N137.

The specific connection relationship is:

The signal is sent to the signal conditioning circuit (4)(5)(6) for filtering after passing through the current transformer (1), the voltage transformer (2) and the DC sampling circuit (3), and the signal conditioning circuit (4)(5)( 6) The output 6 pins are connected with the dual-four-select-one analog switch (7) S ₁ (3 pins), S ₂ (14 pins), S ₃ (6 pins), S ₄ (11 pins) of ADG201, D of ADG201 ₁ (2 pins), D ₂ (15 pins), D ₃ (10 pins), D ₄ (7 pins) connected in parallel, 1N ₂ 1N ₁ 1N ₃ 1N ₄ of ADG201 and DSP processor (10) (TMS320F2812) I/O port connection. A/D converters (8), (9) D ₀ ~ D ₁₅ of A/D976 are connected with D ₀ ~ D ₁₅ of DSP processor (10) (TMS320F2812), 14, 23, 25 pins of A/D976 are connected with The ground is connected in parallel, a capacitor is connected in series between pin 4 and pin 5, and pin 5 is grounded. D _{0 ~ D 7 of DSP processor (10) TMS320F2812 is connected with D 0 ~ D 7 of color} liquid crystal display (11), and I/O ports 30, 33, 36, 39, 54 of DSP processor (10) TMS320F2812 are connected with color /RD, /WR, /CS, A ₀ , A ₁ of the liquid crystal display (11) are connected. The I/O ports 21, 24, and 27 of the DSP processor (10) TMS320F2812 are connected with the pins 25, 26, and 27 of the keyboard (12). The I/O port 147 of the DSP processor (10) TMS320F2812 is connected with the output 6 pins of the photoelectric isolation circuit (13) 6N137, and a resistor is connected in series between the 8 pins and the 6 pins of the photoelectric isolation circuit (13) 6N137, and the 8 pins are connected to the ground A capacitor is connected in series.

The working principle of the utility model is: the AC voltage and current signals are sent to the signal conditioning circuit through the voltage and current transformer, the DC voltage and current signals are sent to the signal conditioning circuit through the DC sampling circuit, and the AC and DC voltage and current signals are filtered by the signal conditioning circuit After that, it is sent to the dual four-selection one analog switch for selection, and then the A/D converter sends the collected signal to the DSP processor for data processing and calculation. The DSP processor is also responsible for the 8.4-inch TFT color LCD display and keyboard processing. The photoelectric isolation circuit isolates the input and output circuits, suppresses system noise, eliminates interference from ground loops, and improves response speed.

Claims (5)

1. A relay protection tester detection device is characterized in that: comprise signal sampling circuit, A/D conversion circuit, DSP processor, photoelectric isolation circuit, color liquid crystal display, keyboard, signal sampling circuit output and A/D conversion The circuit is connected, the A/D conversion circuit is connected with the DSP processor, which is responsible for the sampling and processing of the signal; the DSP processor is responsible for the sampling, processing and calculation of the signal, TFT color LCD display and keyboard processing; the photoelectric isolation circuit and the DSP processor Connected, it is responsible for transmitting signals with light as a medium in the case of electrical isolation, and isolating the input and output circuits. 2. The relay protection tester detection device according to claim 1, characterized in that: the signal sampling circuit comprises a current transformer (1), a voltage transformer (2), a DC sampling circuit (3), a signal conditioning circuit ( 4) (5) (6) and dual four-select one analog switch (7), the A/D conversion circuit includes 6-channel 16-bit A/D converters (8), (9), and the AC output of the relay protection tester The current and voltage are connected to the current transformer (1) and the voltage transformer (2), and the DC current and voltage output by the relay protection tester are connected to the DC sampling circuit (3), and then passed through the signal conditioning circuit (4) (5) (6) be connected with double four to one analog switch (7), realize AC/DC voltage, current sampling and send to signal conditioning circuit and double four to one analog switch (7) to process; Double four to one analog switch (7) ) output signal into the A/D converter (8), (9) for A/D conversion, and the A/D converter (8), (9) is connected with the DSP processor (10) to convert the A/D The signal is sent to the data bus of the I/O port of the DSP processor. 3. The detection device of the relay protection tester according to claim 1 or 2, characterized in that: the dual four-select one analog switch is ADG201, and the A/D sampling chip is AD976. 4. The detection device of the relay protection tester according to claim 1, characterized in that: the DSP processor is a low power consumption DSP microprocessor TMS320F2812. 5. The detection device of relay protection tester according to claim 1, characterized in that: the photoelectric isolation circuit is a high-speed photocoupler optocoupler 6N137.

Images