Testing system and testing method for high-voltage direct-current transmission phase selection closing device

Abstract

The invention provides a test system and a test method for a high-voltage direct-current transmission phase selection closing device, and relates to the technical field of power system automation, and the system comprises the steps that terminal equipment issues a test command to test equipment; the test equipment issues current and voltage related parameters and a current source start-stop instruction to the voltage source and the current source, and issues a closing instruction to the to-be-tested phase selection closing device; the voltage source inputs a reference voltage to the phase selection closing device and the test equipment; the phase selection closing device outputs the phase selection closing instruction to the circuit breaker to enable the circuit breaker to be closed and test equipment; the current transformer collects a current signal on the bus and sends the current signal to the phase selection closing device and the test equipment; the phase selection closing device determines first phase selection closing precision according to the phase selection reference voltage and the current signal; and the test equipment determines the second phase selection closing precision so as to realize the test of the to-be-tested phase selection closing device by comparing the second phase selection closing precision with the first phase selection closing precision. According to the scheme, the test accuracy of the phase selection closing device can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power system automation, and in particular to a testing system and a testing method for a high-voltage direct current transmission phase selection closing device. Background Art

[0002] High-voltage circuit breakers are commonly used in high-voltage DC transmission converter stations to switch on and off various loads and load currents. The performance of high-voltage circuit breakers and the stability of the opening and closing processes are directly related to the safe and stable operation of the power system. Opening and closing operations often bring about changes in the operating mode of the power system, and then produce transient phenomena such as opening and closing inrush current and overvoltage, which have a negative impact on the stable operation of power equipment and the service life of the equipment.

[0003] The phase-selective closing device can control the circuit breaker to complete the opening and closing at the most favorable phase of voltage or current, thereby eliminating electromagnetic transient effects such as surge current and overvoltage generated in the process. It is used to control the switching of high-voltage circuit breakers of equipment such as capacitors, reactors, and transformers.

[0004] However, as the phase-selective closing device is affected by the aging of the auxiliary contacts of the circuit breaker after long-term switching, the closing accuracy will decrease. Inappropriate phase-selective control parameters or the accuracy of the phase-selective closing device itself will also affect the results of the phase-selective closing device. For example, if the AC filter is not closed at the voltage zero point, it may trigger the predicted action of the DC transmission system commutation failure. Moreover, with the continuous expansion of the scale of high-voltage DC transmission, the control accuracy of the phase-selective closing device has an increasingly prominent impact on the entire power grid, so it is necessary to test the control accuracy and reliability of the phase-selective closing device.

[0005] The current testing scheme for phase-selective closing devices mainly uses a phase-selective closing tester in conjunction with a large current generator and a wave recording device to achieve the test function. However, this method not only has a single test function, but also cannot accurately capture the action moment of the phase-selective closing device, that is, it cannot accurately capture key parameters such as the closing time, resulting in low accuracy of the test results of the phase-selective closing device. Summary of the invention

[0006] In view of this, in order to address the above shortcomings, it is necessary to provide a test system and a test method for a high-voltage direct current transmission phase selection and closing device to improve the test accuracy of the phase selection and closing device.

[0007] In a first aspect, the present invention provides a test system for a high-voltage direct current transmission phase-selection closing device, the system comprising: a test device, a terminal device, a voltage source, a current source, a phase-selection closing device to be tested, a circuit breaker and a current transformer; the terminal device is respectively connected to the test device and the voltage source for communication, the voltage source and the current source are wirelessly connected, the test device is respectively electrically connected to the phase-selection closing device to be tested and the current transformer, the voltage source is respectively electrically connected to the test device and the phase-selection closing device to be tested, the phase-selection closing device to be tested is respectively electrically connected to the circuit breaker and the current transformer, and the circuit breaker is respectively electrically connected to the current source and the current transformer; The terminal device is used for the operator to input the test command and send the test command to the test device; The test equipment is used to send voltage-related parameters, current-related parameters and current source start and stop instructions to the voltage source and the current source; and send a closing instruction to the phase-selected closing device to be tested; The voltage source is used to generate a phase selection reference voltage, and input it to the phase selection closing device to be tested and the test equipment respectively; The phase selection closing device to be tested is used to select the zero-crossing moment to output the phase selection closing instruction to the circuit breaker according to the closing instruction and the phase selection reference voltage, so as to close the circuit breaker; at the same time, the phase selection closing instruction is output to the test equipment; The current transformer is used to collect the current signal on the busbar after the circuit breaker is closed, and send it to the phase selection closing device to be tested and the test equipment respectively; The phase selection and closing device to be tested is further used to determine the first phase selection and closing accuracy according to the received phase selection reference voltage and current signals; The test equipment is also used to determine the second phase selection closing accuracy based on the received phase selection reference voltage and current signals, so that the operator can compare it with the first phase selection closing accuracy to implement the test of the phase selection closing device to be tested.

[0008] Preferably, the voltage source and the current source are in phase with each other through wireless communication.

[0009] Preferably, the terminal device and the test device are connected to each other via the Modbus TCP communication protocol.

[0010] Preferably, the test equipment is configured with a general processor board, an AC / DC conversion board, a high-speed AD acquisition board, a high-speed optical fiber communication board and an open-input and open-output board.

[0011] Preferably, the test equipment adopts a standard 4U industrial computer size chassis and is equipped with a high-speed serial backplane bus.

[0012] Preferably, the minimum interrupt task period of the general processor board is 10 microseconds.

[0013] Preferably, the transmission delay of the high-speed fiber optic communication board is less than 1 microsecond.

[0014] Preferably, the maximum sampling frequency of the high-speed AD acquisition board is not less than 800 kHz, and the conversion time is less than 1 microsecond.

[0015] Preferably, the test device is also configured with a graphical editing module for users to perform secondary development according to different application scenarios of the converter station.

[0016] In a second aspect, the present invention further provides a method for testing a high-voltage direct current transmission phase selection and closing device, the method being implemented based on a test system for a high-voltage direct current transmission phase selection and closing device as described in any one of the first aspects, the method comprising: Step 101: An operator inputs a test command through a terminal device, and the terminal device sends the test command to a test device; Step 102: Using the test equipment to send voltage-related parameters, current-related parameters and current source start and stop instructions to the voltage source and the current source; Step 103: using a voltage source to generate a phase selection reference voltage according to voltage-related parameters, and inputting the phase selection reference voltage to the phase selection closing device to be tested and the test equipment respectively; Step 104: using the test equipment to issue a closing command to the phase-selected closing device to be tested; Step 105: using the phase-selective closing device to be tested to determine a target time for outputting a closing command to the circuit breaker according to the received closing command and the phase-selective reference voltage, and outputting a closing command to the circuit breaker and the test equipment respectively at the target time; Step 106: Utilizing the circuit breaker to perform a closing operation upon receiving a closing instruction; Step 107: using a current transformer to collect a current signal generated by a current source on the busbar after the circuit breaker is closed, and sending the current signal to the phase-selected closing device to be tested and the test equipment respectively; Step 108: using the phase selection closing device to be tested to determine the first phase selection closing accuracy representing whether the closing operation is performed when the voltage passes through zero point according to the received phase selection reference voltage and current signals; Step 109: using the test equipment to determine the second phase selection closing accuracy, which indicates whether the closing operation is performed when the voltage crosses zero, based on the received phase selection reference voltage and current signals; Step 110: Compare the first phase selection and closing accuracy with the second phase selection and closing accuracy to implement a test on the phase selection and closing device to be tested.

[0017] It can be seen from the above technical scheme that in the test system and test method of the high-voltage direct current transmission phase-selective closing device provided by the present invention, the method is implemented based on the test system of the high-voltage direct current transmission phase-selective closing device, and the system includes test equipment, terminal equipment, voltage source, current source, the phase-selective closing device to be tested, circuit breaker and current transformer. During the test, the operator inputs the test command through the terminal equipment, and the terminal equipment sends the test command to the test equipment, and the test equipment sends voltage-related parameters, current-related parameters and current source start and stop instructions to the voltage source and current source; further, the voltage source will generate a phase-selective reference voltage according to the voltage-related parameters, and transmit the generated phase-selective reference voltage to the phase-selective closing device to be tested and the test equipment; further, the test equipment sends a closing instruction to the phase-selective closing device to be tested, and the phase-selective closing device to be tested will determine the target time to output the closing instruction to the circuit breaker according to the closing instruction and the phase-selective reference voltage, and at At this target moment, a closing command is output to the circuit breaker and the test equipment; after the closing command is output, the circuit breaker is closed, and current is generated in the busbar. At this time, the AC transformer will collect the current signal on the busbar and send it to the phase-selection closing device and the test equipment to be tested. The phase-selection closing device and the test equipment to be tested use the received current signal and the phase-selection reference voltage to determine the execution time of the closing operation, and judge the deviation between the execution time of the closing operation and the voltage zero-crossing time. Further, the test result of the phase-selection closing device to be tested can be verified according to the result of the test equipment judgment, thereby realizing the test of the phase-selection closing device to be tested. It can be seen that in this scheme, current can be generated in the busbar at the moment of circuit breaker closing, and the current transformer can capture the closing action moment of the phase-selection to be tested by collecting the current signal in the busbar in real time and sending it to the test equipment, and accurately measure key parameters such as the closing time, thereby improving the test accuracy of the phase-selection closing device. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of a test system for a high-voltage direct current transmission phase selection and closing device provided in an embodiment of the present invention.

[0019] Figure 2 A flow chart of a method for testing a high-voltage direct current transmission phase selection and closing device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] like Figure 1As shown, the present invention provides a test system for a high-voltage direct current transmission phase-selection closing device, the system comprising: a test device, a terminal device, a voltage source, a current source, a phase-selection closing device to be tested, a circuit breaker and a current transformer; the terminal device is respectively connected to the test device and the voltage source for communication, the voltage source and the current source are connected to each other for wireless communication, the test device is respectively electrically connected to the phase-selection closing device to be tested and the current transformer, the voltage source is respectively electrically connected to the test device and the phase-selection closing device to be tested, the phase-selection closing device to be tested is respectively electrically connected to the circuit breaker and the current transformer, and the circuit breaker is respectively electrically connected to the current source and the current transformer; The terminal device is used for the operator to input the test command and send the test command to the test device; The test equipment is used to send voltage-related parameters, current-related parameters and current source start and stop instructions to the voltage source and the current source; and send a closing instruction to the phase-selected closing device to be tested; A voltage source is used to generate a phase selection reference voltage and input it to the phase selection closing device to be tested and the test equipment respectively; The phase selection closing device to be tested is used to select the zero-crossing point moment to output the phase selection closing command to the circuit breaker according to the closing command and the phase selection reference voltage, so as to close the circuit breaker; at the same time, the phase selection closing command is output to the test equipment; The current transformer is used to collect the current signal on the busbar after the circuit breaker is closed, and send it to the phase selection closing device to be tested and the test equipment respectively; The phase selection closing device to be tested is also used to determine the first phase selection closing accuracy according to the received phase selection reference voltage and current signals; The test equipment is also used to determine the second phase selection closing accuracy based on the received phase selection reference voltage and current signals, so that the operating personnel can compare it with the first phase selection closing accuracy to realize the test of the phase selection closing device to be tested.

[0022] In this embodiment, the terminal device can be integrated into the test device, or can be an independent terminal device. The terminal device and the test device can be connected to each other through the Modbus TCP communication protocol.

[0023] The test equipment can use a standard 4U industrial computer size chassis and be equipped with a high-speed serial backplane bus. The test equipment should also be equipped with a general processor board, an AC / DC conversion board, a high-speed AD acquisition board, a high-speed optical fiber communication board, and an input / output board to meet various functional test and IO interface requirements.

[0024] For example, the minimum interrupt task cycle of a high-performance general-purpose processor board should be no more than 10 microseconds, so that task synchronization can be achieved under 100kHz high-speed sampling, achieving the purpose of simultaneous acquisition and simultaneous calculation.

[0025] For example, the maximum sampling frequency of the configured high-speed AD acquisition board should be no less than 800kHz, and the conversion time should be less than 1 microsecond. This, combined with high-precision hardware phase-locking and frequency tracking control technology, can meet the high-precision analog measurement requirements of the instrument level.

[0026] For another example, the transmission delay of the configured high-speed fiber optic communication board should be less than 1 microsecond, which can further improve the acquisition speed of the secondary side DC quantity.

[0027] In this way, by configuring the performance parameters of each board, the time for processing response, collection and communication processes can be greatly reduced, thereby greatly improving the accuracy of the execution time of the closing operation determined by the test equipment, thereby improving the accuracy of testing the closing device of the selected phase.

[0028] The test equipment can also be configured with a graphical editing module to meet the user's secondary development needs. Users can integrate their own test methods according to different application scenarios of the converter station, that is, they can flexibly modify the test strategy and status assessment standards.

[0029] In addition, in order to ensure the convenience of subsequent comparison of the reference voltage and current signal, the phase of the phase-selected reference voltage and the current signal can be made consistent, that is, their phase relationship is ensured not to change during the operation of the system. Specifically, the phase of the phase-selected reference voltage and the current signal is made consistent through wireless communication between the voltage source and the current source.

[0030] like Figure 2 As shown, the present invention also provides a test method for a high-voltage direct current transmission phase selection closing device, the test method is implemented based on a test system for a high-voltage direct current transmission phase selection closing device as described above, and the method comprises: Step 101: An operator inputs a test command through a terminal device, and the terminal device sends the test command to a test device; Step 102: Using the test equipment to send voltage-related parameters, current-related parameters and current source start and stop instructions to the voltage source and the current source; Step 103: using a voltage source to generate a phase selection reference voltage according to voltage-related parameters, and inputting the phase selection reference voltage to the phase selection closing device to be tested and the test equipment respectively; Step 104: using the test equipment to issue a closing command to the phase-selected closing device to be tested; Step 105: using the phase-selective closing device to be tested to determine a target time for outputting a closing command to the circuit breaker according to the received closing command and the phase-selective reference voltage, and outputting a closing command to the circuit breaker and the test equipment respectively at the target time; Step 106: Utilizing the circuit breaker to perform a closing operation upon receiving a closing instruction; Step 107: using a current transformer to collect a current signal generated by a current source on the busbar after the circuit breaker is closed, and sending the current signal to the phase-selected closing device to be tested and the test equipment respectively; Step 108: using the phase selection closing device to be tested to determine the first phase selection closing accuracy representing whether the closing operation is performed when the voltage passes through zero point according to the received phase selection reference voltage and current signals; Step 109: using the test equipment to determine the second phase selection closing accuracy, which indicates whether the closing operation is performed when the voltage crosses zero, based on the received phase selection reference voltage and current signals; Step 110: Compare the first phase selection closing accuracy with the second phase selection closing accuracy to implement a test of the phase selection closing device to be tested.

[0031] In this embodiment, first, the user inputs a test command in the terminal device, and the terminal device sends the test command to the test device through Modbus TCP; the test device sends the set voltage, current and other related parameters, as well as the current source start and stop instructions to the wireless communication module, and the wireless communication module distributes it to the voltage source and the current source to achieve synchronous response of the voltage source and the current source; further, the phase selection closing device and the test device will simultaneously collect the phase selection reference voltage of the voltage source; the test device sends the closing command to the phase selection closing device through the DO output board, and the phase selection closing device selects the appropriate time to output the closing command to the circuit breaker after internal logic processing, and outputs it to the DI input board of the test device at the same time; the circuit breaker receives the closing command and executes the closing operation, and the system CT (current transformer) collects the current signal on the bus and sends it to the phase selection closing device and the test device; the phase selection closing device analyzes the accuracy information of the closing time according to the phase selection reference voltage and current signal. At the same time, the test equipment will determine the closing state and calculate the closing accuracy based on the phase selection reference voltage, the DO board output signal, the DI board input signal, and the current signal light collected by the system CT. In this way, by comparing the closing accuracy determined by the test equipment and the closing accuracy determined by the phase selection closing device, it can be determined whether the closing control accuracy of the phase selection closing device is accurate. In addition, the test equipment can also have a built-in fault recording module to collect waveform data to generate a detailed test report, providing users with intuitive, accurate and traceable test results, which is convenient for subsequent evaluation and analysis of the performance of the phase selection closing device.

[0032] The method embodiment and system embodiment provided by the present invention are based on the same inventive concept. For detailed description, please refer to the system embodiment, which will not be described in detail here.

[0033] In summary, in the test system and test method of the high-voltage direct current transmission phase-selecting closing device provided by the present invention, the test equipment of the system is developed based on a high-performance general control and protection platform, and has high-speed data acquisition function, high-speed data communication function, high-speed data processing function, built-in fault recording function, image secondary development function, etc. Through close cooperation with standard voltage source, standard current source and wireless communication method, key parameters such as the action moment, closing time and accuracy of the phase-selecting closing device can be measured more accurately. Further, a detailed test report is generated based on the judged closing state and closing accuracy, which provides users with intuitive and accurate test results, and is also convenient for users to further evaluate and analyze the performance of the phase-selecting closing device.

[0034] The modules or units in the device of the embodiment of the present invention can be combined, divided and deleted according to actual needs. The above disclosure is only the preferred embodiment of the present invention, and of course it cannot be used to limit the scope of the rights of the present invention. Those skilled in the art can understand that all or part of the processes of the above embodiment are implemented, and the equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A test system for a high voltage direct current transmission phase selection closing device, characterized in that: The system comprises: a test device, a terminal device, a voltage source, a current source, a closing device for a selected phase to be tested, a circuit breaker and a current transformer; the terminal device is respectively connected to the test device and the voltage source for communication, the voltage source and the current source are connected to each other for wireless communication, the test device is respectively electrically connected to the closing device for the selected phase to be tested and the current transformer, the voltage source is respectively electrically connected to the test device and the closing device for the selected phase to be tested, the closing device for the selected phase to be tested is respectively electrically connected to the circuit breaker and the current transformer, and the circuit breaker is respectively electrically connected to the current source and the current transformer; The terminal device is used for the operator to input the test command and send the test command to the test device; The test equipment is used to send voltage-related parameters, current-related parameters and current source start and stop instructions to the voltage source and the current source; and send a closing instruction to the phase-selected closing device to be tested; The voltage source is used to generate a phase selection reference voltage, and input it to the phase selection closing device to be tested and the test equipment respectively; The phase selection closing device to be tested is used to select the zero-crossing moment to output the phase selection closing instruction to the circuit breaker according to the closing instruction and the phase selection reference voltage, so as to close the circuit breaker; at the same time, the phase selection closing instruction is output to the test equipment; The current transformer is used to collect the current signal on the busbar after the circuit breaker is closed, and send it to the phase selection closing device to be tested and the test equipment respectively; The phase selection and closing device to be tested is further used to determine the first phase selection and closing accuracy according to the received phase selection reference voltage and current signals; The test equipment is also used to determine the second phase selection closing accuracy based on the received phase selection reference voltage and current signals, so that the operator can compare it with the first phase selection closing accuracy to implement the test of the phase selection closing device to be tested.

2. The test system for the high-voltage direct current transmission phase selection closing device according to claim 1 is characterized in that: The voltage source and the current source are in phase with each other through wireless communication.

3. The test system for the high voltage direct current transmission phase selection closing device according to claim 1, characterized in that: The terminal device and the test device are connected via Modbus TCP communication protocol.

4. The test system for the high voltage direct current transmission phase selection closing device according to claim 1, characterized in that: The test equipment is equipped with a general processor board, an AC / DC conversion board, a high-speed AD acquisition board, a high-speed optical fiber communication board and an open-input and open-output board.

5. The test system for the high voltage direct current transmission phase selection closing device according to claim 4, characterized in that: The test equipment adopts a standard 4U industrial computer size chassis and is equipped with a high-speed serial backplane bus.

6. The test system for the high-voltage direct current transmission phase selection and closing device according to claim 4, characterized in that: The minimum interrupt task cycle of the general processor board is 10 microseconds.

7. The test system for the high-voltage direct current transmission phase selection and closing device according to claim 4, characterized in that: The transmission delay of the high-speed optical fiber communication board is less than 1 microsecond.

8. The test system for the high voltage direct current transmission phase selection closing device according to claim 4, characterized in that: The highest sampling frequency of the high-speed AD acquisition board is not less than 800kHz, and the conversion time is less than 1 microsecond.

9. The test system for the high-voltage direct current transmission phase selection and closing device according to claim 1, characterized in that: The test equipment is also configured with a graphical editing module for users to perform secondary development according to different application scenarios of the converter station.

10. A method for testing a high voltage direct current transmission phase selection closing device, characterized in that: The test method is implemented based on the test system of the high-voltage direct current transmission phase selection closing device as claimed in any one of claims 1 to 9, and the method comprises: Step 101: An operator inputs a test command through a terminal device, and the terminal device sends the test command to a test device; Step 102: Using the test equipment to send voltage-related parameters, current-related parameters and current source start and stop instructions to the voltage source and the current source; Step 103: using a voltage source to generate a phase selection reference voltage according to voltage-related parameters, and inputting the phase selection reference voltage to the phase selection closing device to be tested and the test equipment respectively; Step 104: using the test equipment to issue a closing command to the phase-selected closing device to be tested; Step 105: using the phase-selective closing device to be tested to determine a target time for outputting a closing command to the circuit breaker according to the received closing command and the phase-selective reference voltage, and outputting a closing command to the circuit breaker and the test equipment respectively at the target time; Step 106: Utilizing the circuit breaker to perform a closing operation upon receiving a closing instruction; Step 107: using a current transformer to collect a current signal generated by a current source on the busbar after the circuit breaker is closed, and sending the current signal to the phase-selected closing device to be tested and the test equipment respectively; Step 108: using the phase selection closing device to be tested to determine the first phase selection closing accuracy representing whether the closing operation is performed when the voltage crosses zero point according to the received phase selection reference voltage and current signals; Step 109: using the test equipment to determine the second phase selection closing accuracy, which indicates whether the closing operation is performed when the voltage crosses zero, based on the received phase selection reference voltage and current signals; Step 110: Compare the first phase selection and closing accuracy with the second phase selection and closing accuracy to implement a test on the phase selection and closing device to be tested.

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