Circuit breaker opening and closing main and auxiliary contact time difference test system and method

Abstract

The invention discloses a circuit breaker time difference test system. The system comprises a circuit breaker to be tested and a tester, wherein the circuit breaker is provided with a phase selection closing device; a port binding post on one side of a fracture of the circuit breaker is short-circuited and connected to an N binding post of the tester, and port binding posts A, B and C on the other side are connected to corresponding binding posts A1, B1 and C1 in a first connecting phase of the tester; in addition, a port binding post on one side of a pair of normally-open auxiliary contacts of the circuit breaker is connected with a wire connected to an N binding post of the tester, and a port binding post on the other side of the normally-open auxiliary contacts is connected to a binding post A2 of a second phase of the tester; when the tester is used for testing the characteristics of the circuit breaker, besides the action time and synchronism of three-phase contacts of the circuit breaker are measured, corresponding auxiliary contacts of the circuit breaker are connected at the same time, operation is carried out according to testing regulations, the time difference of the main contacts and the auxiliary contacts during closing and opening of the circuit breaker can be accurately measured, and a basis can be provided for setting of related fixed values such as fast switching.

Description

Technical Field

[0001] This invention belongs to the field of power generation technology, specifically relating to a test system and method for the time difference between the main and auxiliary contacts of a circuit breaker. Background Technology

[0002] When a high-voltage circuit breaker in a 6kV or higher system opens or closes, it is necessary to measure the time difference between the opening and closing of the main contacts and the auxiliary contacts of the circuit breaker mechanism to provide a basis for setting relevant device parameters. Currently, this measurement is rarely performed on circuit breakers. For 6kV and 10kV power supply incoming circuit breakers in plant systems, and for 220kV and higher circuit breakers, the usual method is to check the fault recorder and compare the timing of the AC current with the timing of the position feedback contacts. However, comparing the time of the circuit breaker current appearance and disappearance with the recording time of the circuit breaker's auxiliary contact starting switch using the fault recorder only provides a rough estimate and cannot provide precise measurement. Analysis and comparison using fault recorder waveforms also results in large errors, inaccurate data, and a relatively coarse approach with significant inaccuracies. Summary of the Invention

[0003] In view of the above situation and to overcome the defects of the prior art, the technical solution adopted by the present invention is as follows: A circuit breaker time difference testing system includes a circuit breaker under test equipped with a phase selection closing device and a tester; characterized in that: the terminal of one side of the circuit breaker's break point is short-circuited and connected to the N terminal of the tester, and the terminals A, B, and C of the other side of the circuit breaker are connected to the corresponding terminals A1, B1, and C1 of the first phase of the tester; in addition, one side of the terminal of a pair of normally open auxiliary contacts of the circuit breaker is connected to the line connected to the N terminal of the tester, and the terminal of the other side of the terminal is connected to the terminal A2 of the second phase of the tester.

[0004] A test method for a circuit breaker testing system, characterized by comprising: Step 1: Connect the tester; Step 2: Test the condition of each component; Step 3: Perform a single measurement. When the three-phase switch is in the open state, press the close button. After the close button outputs a close signal, it drives the motor to rotate forward and drive the circuit breaker to close. At the same time, the tester starts timing and begins to measure the closing time of the three-phase switch and auxiliary contacts. The closing time of the three-phase switch and auxiliary contacts is recorded. After the circuit breaker closes, the corresponding time difference value displayed on the tester can be read to accurately determine the time difference between the main and auxiliary contacts when the circuit breaker closes. When the three-phase switch is in the closed state, press the open button. After the open button outputs a open signal, it drives the motor to rotate in reverse and drive the circuit breaker to open. At the same time, the tester starts timing and begins to measure the opening time of the three-phase switch and auxiliary contacts. The opening time of the three-phase switch and auxiliary contacts is recorded. After the circuit breaker opens, the corresponding time difference value displayed on the tester can be read to accurately determine the time difference between the main and auxiliary contacts when the circuit breaker opens. Step 4: Perform multiple measurements and data processing; Step 5: Data trend display output and adjustment.

[0005] Compared with the prior art, the present invention has the following beneficial effects: When testing the characteristics of a circuit breaker using a testing instrument, this application measures the operating time and synchronicity of the three-phase contacts of the circuit breaker, while simultaneously connecting the corresponding auxiliary contacts. Following the testing procedures, the time difference between the main and auxiliary contacts during circuit breaker closing and opening can be accurately measured. Accurately measuring the time difference between the main and auxiliary contacts during circuit breaker opening and closing provides a basis for setting related parameters such as fast-switching. Attached Figure Description

[0006] Figure 1 This is a diagram illustrating the system connections. Detailed Implementation The present invention will be further described below with reference to the accompanying drawings and embodiments. The embodiments of the present invention include, but are not limited to, the following embodiments.

[0007] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is described as "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is described as "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," "top," "bottom," and similar expressions used in this document are for illustrative purposes only.

[0008] An embodiment of the present invention provides a circuit breaker testing method, which is applied to, for example... Figure 1 The circuit breaker time difference test system shown includes a tester; the system also includes a circuit breaker under test equipped with a phase selection closing device, and the circuit breaker under test is connected to the tester. like Figure 1 The diagram shows a circuit breaker testing system, including the circuit breaker under test and the testing instrument. The circuit breaker under test can be a set of three-phase double-break circuit breakers. The testing instrument can provide DC or AC control power to the circuit breaker under test and can control the opening and closing of the circuit breaker under test. The measurement accuracy meets the requirements of relevant regulations.

[0009] The specific methods and steps include: Step 1: Connecting the Tester. Short-circuit the terminals on one side of the circuit breaker and connect them to the N terminal of the tester. Connect the terminals A, B, and C on the other side of the circuit breaker to the corresponding terminals A1, B1, and C1 of the first phase of the tester. Additionally, connect one terminal of a pair of normally open auxiliary contacts from the circuit breaker to the wire connected to the N terminal of the tester, and connect the other terminal to terminal A2 of the second phase of the tester.

[0010] When testing the characteristics of a circuit breaker using a tester, in addition to measuring the operating time and synchronicity of the three-phase contacts of the circuit breaker, the corresponding auxiliary contacts of the circuit breaker should also be connected. By operating according to the test procedure, the time difference between the main and auxiliary contacts when the circuit breaker is closed and opened can be accurately measured.

[0011] Step 2: Test the condition of each component.

[0012] To check if the circuit breaker under test is functioning properly, manually test its opening and closing. After the self-test of the tester is normal, input the information of the circuit breaker under test into the human-machine interface. Verify the operation of the circuit breaker under test via the panel buttons of the tester, and check the accuracy and timeliness of the opening and closing position information fed back from the main and auxiliary contacts of the circuit breaker. Step 3: Perform a single measurement.

[0013] The circuit breaker under test is tested using the aforementioned tester. When the three-phase switch is in the open state, pressing the close button outputs a close signal, which drives the motor to rotate forward and close the circuit breaker. Simultaneously, the tester starts timing and measures the closing time of the three-phase switch and auxiliary contacts. The closing time of the three-phase switch and auxiliary contacts is recorded and displayed in a bar chart. After the circuit breaker closes, the corresponding time difference value displayed on the tester can accurately determine the time difference between the main and auxiliary contacts when the circuit breaker closes. Alternatively, when the three-phase switch is in the closed state, pressing the open button outputs a open signal, which drives the motor to rotate in reverse and open the circuit breaker. Simultaneously, the tester starts timing and measures the opening time of the three-phase switch and auxiliary contacts. The opening time of the three-phase switch and auxiliary contacts is recorded and displayed in a bar chart. After the circuit breaker opens, the corresponding time difference value displayed on the tester can accurately determine the time difference between the main and auxiliary contacts when the circuit breaker opens. Step 4: Perform multiple measurements and data processing.

[0014] Perform multiple tests and save the test data each time. Select complete, true and reasonable records from the test data and save them. If an error occurs, press the stop button to stop the test. Data processing includes data filtering and data statistics; During data screening, test data are obtained under the boundary condition that the rated voltage of the control circuit of the circuit breaker under test meets the reliable operating voltage. The maximum and minimum closing times of the test data differ from the average closing time by less than the preset closing time difference, and the maximum and minimum opening times differ from the average opening time by less than the preset opening time difference. Abnormal data are discarded.

[0015] During data analysis, a pre-set statistical model is used to process multiple test data to obtain test statistics. Specifically, the preset statistical model can include Z-test, T-test, chi-square test or F-test, etc. In some examples, the T-test can be used to analyze the relationship between categorical data and quantitative data and obtain the test statistic. For example, the T-test can be used to describe the overall opening and closing time dispersion of the circuit breaker under test. The test statistic can be a statistic used for hypothesis testing calculation. The test statistic can be obtained based on the standard deviation.

[0016] The test results of the circuit breaker under test are output based on the test statistic. Specifically, the test results of the circuit breaker under test can be obtained based on the selected statistical significance level; in some examples, the statistical significance level is 0.05. The test results of the circuit breaker under test can be the test results of the circuit breaker's opening and closing time dispersion. In some examples, if the test results of the circuit breaker under test are qualified, it is determined that the phase selection closing device of the circuit breaker under test operates reasonably and the overall opening and closing time dispersion is good; otherwise, it is determined that the phase selection closing device of the circuit breaker under test operates unreasonably and the overall opening and closing time dispersion is poor.

[0017] By using a pre-set statistical model to objectively describe the overall state of a set of circuit breakers based on the test data of the circuit breakers under test, a basis is provided for better assessment of the circuit breaker status.

[0018] Step 5: Data trend display output and adjustment.

[0019] Press the trend chart button on the tester to display the trend chart on the output trend chart interface and analyze and judge the analysis results. The trend chart includes test data and standard data. The opening and closing action time data of the circuit breaker should be within the acceptable range of the acceptance standard, and should be within the allowable error range when compared with the factory test data. If it does not meet the specifications, the circuit breaker under test should be adjusted accordingly, and then retested until the action data is qualified. Step 6: Disconnect the test wiring, save the test data, and complete the circuit breaker test.

[0020] In a specific application embodiment, 60 sets of test data for a three-phase double-break circuit breaker under test with a DC rated voltage of 100% or an AC rated voltage of 100% are analyzed using a T-test. It should be noted that each set of test data for the circuit breaker includes three phases, with each phase having two breaks. Each phase is tested 20 times. Each set of data for the circuit breaker under test consists of the time data measured at the two breaks in one phase. A significance level of 0.05 is set. Referring to the t-table, t4,0.05 = 2.78. If t is less than t4,0.05, the circuit breaker closing time dispersion meets the equipment operation requirements, and the test ends. Otherwise, the travel speed of the circuit breaker's operating mechanism is adjusted, and the status of the circuit breaker under test is rechecked. Since the discrete characteristics of circuit breakers are affected not only by the triggering time of control circuit devices and phase selection closing devices, but also by the inconsistent stroke of the operating mechanisms of each phase, the stroke speed of the operating mechanism of the circuit breaker under test is adjusted according to the test results of the circuit breaker under test. This optimizes and adjusts the inconsistent stroke of the operating mechanisms of each phase of the circuit breaker, thereby improving the stability of the consistency of opening and closing times between the break points.

[0021] This application also provides a circuit breaker testing device, the device comprising: The data acquisition module is used to acquire the opening and closing test data of the circuit breaker under test based on the status test results of the circuit breaker under test, provided that the circuit breaker under test meets the preset circuit debugging conditions. The test analysis module is used to process the closing test data using a preset statistical model and obtain test statistics. The result acquisition module is used to output the test results of the circuit breaker under test based on the test statistics.

[0022] The data acquisition module is used to acquire the opening and closing test data of the circuit breaker under test when the status test results of the circuit breaker under test meet the preset standard range.

[0023] The data acquisition module is used to acquire opening and closing test data under the boundary condition that the rated voltage of the control circuit of the circuit breaker under test meets the reliable operating voltage. The maximum closing time and minimum closing time of the test data are less than the preset closing time difference from the average closing time, and the maximum opening time and minimum opening time are less than the preset opening time difference from the average opening time.

[0024] A circuit breaker tester is provided, comprising a processor, memory, network interface, display screen, and input devices connected via a system bus. The processor provides computational and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The network interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements a circuit breaker testing method. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the tester's housing, or an external keyboard, touchpad, or mouse, etc.

[0025] A circuit breaker time difference testing system is provided, such as Figure 1 As shown, the system includes the circuit breaker tester mentioned above; the system also includes a circuit breaker under test equipped with a phase selection closing device, and the circuit breaker under test is connected to the circuit breaker tester.

[0026] This application provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the above-described method.

[0027] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0028] In the description of this specification, the references to terms such as "some embodiments," "other embodiments," "ideal embodiments," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example that are included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0029] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0030] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A circuit breaker time differential test system, the system comprising a circuit breaker to be tested provided with a selected phase closing device, a tester; characterized in that: The port terminal of one side of the breaker is short-circuited and connected to the N terminal of the tester, and the port terminals of the other side are connected to the corresponding terminals A1, B1 and C1 of the first phase of the tester; in addition, one side of a pair of normally open auxiliary contacts of the breaker is connected to the N terminal of the tester, and the other side is connected to the terminal A2 of the second phase of the tester.

2. The circuit breaker time difference test system according to claim 1, wherein, the tester comprises: a data acquisition module configured to acquire the closing and opening test data of the circuit breaker to be tested according to the state test result of the circuit breaker to be tested when the circuit breaker to be tested meets the preset loop debugging condition; a verification analysis module configured to acquire a verification statistic by processing the closing test data using a preset statistical model; a result acquisition module configured to output the test result of the circuit breaker to be tested according to the verification statistic.

3. The circuit breaker time difference test system according to claim 2, wherein, the data acquisition module is configured to acquire the closing and opening test data of the circuit breaker to be tested when the state test result of the circuit breaker to be tested meets a preset standard range.

4. The circuit breaker time difference test system according to claim 3, wherein, the data acquisition module is configured to acquire the closing and opening test data when the control loop rated voltage of the circuit breaker to be tested meets the boundary condition of reliable action voltage; and the condition that the test result meets the preset standard range is that the maximum closing time, the minimum closing time and the average closing time of the test data respectively differ by less than a preset closing time difference, and the maximum opening time, the minimum opening time and the average opening time of the test data respectively differ by less than a preset opening time difference.

5. A test method based on the test system of claim 1, wherein, the method comprises the following steps: Step 1: tester connection; Step 2: test each component state; Step 3: perform single measurement; when the three-phase switch is in the opening state, press the closing button, and after the closing button outputs the closing signal, drive the motor to rotate in the positive direction to drive the circuit breaker to close, at the same time, the tester starts timing and begins to measure the closing time of the three-phase switch and the auxiliary contact, and records the closing time of the three-phase switch and the auxiliary contact; after the circuit breaker is closed, the corresponding time difference value displayed on the tester can be read to accurately obtain the main auxiliary contact time difference when the circuit breaker is closed; when the three-phase switch is in the closing state, press the opening button, and after the opening button outputs the opening signal, drive the motor to rotate in the reverse direction to drive the circuit breaker to open, at the same time, the tester starts timing and begins to measure the opening time of the three-phase switch and the auxiliary contact, and records the opening time of the three-phase switch and the auxiliary contact; after the circuit breaker is opened, the corresponding time difference value displayed on the tester can be read to accurately obtain the main auxiliary contact time difference when the circuit breaker is opened; Step 4: perform multiple measurements and data processing; Step 5: data trend display output and calibration.

6. The test method according to claim 5, wherein, in Step 2, The manual test is combined with whether the tested circuit breaker is normal, the switch of the tester is opened for self-checking, the information of the tested circuit breaker is input on the man-machine interface after the self-checking is normal, whether the action of the tested circuit breaker is normal through the panel button operation of the tester, and whether the combined and separated position information fed back by the main contact and the auxiliary contact of the connected circuit breaker is accurate and timely.

7. The test method according to claim 5, wherein, In step four, Data processing includes data screening and data statistics; when data screening, the test data is obtained under the boundary condition that the control loop rated voltage of the tested circuit breaker meets the reliable action voltage; the maximum closing time, the minimum closing time of the test data respectively differ from the average closing time by less than the preset closing time difference, the maximum opening time, the minimum opening time respectively differ from the average opening time by less than the preset opening time difference; the abnormal data is eliminated.

8. The test method according to claim 7, wherein, When data statistics, the preset statistical model is used to process the test data for multiple times to obtain the test statistic; The preset statistical model includes Z test, T test, chi-square test or F test; The test result of the tested circuit breaker is output according to the test statistic, and the test result of the tested circuit breaker can be obtained according to the selected statistical significant level.

9. The test method according to claim 5, wherein, In step five, The trend graph button of the tester is pressed, the trend graph interface is output to display the trend graph and analyze the analysis result, the test data and the standard data are included in the trend graph, the opening and closing action time data of the circuit breaker should be in the acceptance standard qualified range, and the factory test data should be in the error allowable range, if not, the tested circuit breaker is adjusted accordingly, and then retested until the action data is qualified.

10. The test method according to claim 5, wherein, Further comprising, Step six, the test wiring is removed, the test data is saved, and the circuit breaker test is completed.

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