Transformer testing device and control method thereof

Abstract

The invention discloses a transformer testing device and a control method thereof. Relates to the field of transformer testing. The input side of the inversion unit is connected with the energy storage unit, and the output side is connected with the to-be-detected transformer; the change-over switch comprises two groups of switches, when the first group of switches is switched on and the second group of switches is switched off, the impedance value of the transformer to be detected is measured, and when the first group of switches is switched off and the second group of switches is switched on, a short-circuit test is carried out; the impedance measuring unit is used for measuring the impedance value of the transformer to be detected; the to-be-detected transformer is connected with the change-over switch, is connected with the impedance measurement unit when the first group of switches are closed, and is used for measuring an impedance value, and is connected with the inversion unit when the second group of switches are closed, and is used for carrying out a short-circuit test; and the control unit is connected with the energy storage unit, the inversion unit, the change-over switch, the impedance measurement unit and the to-be-detected transformer, and the problem of low detection efficiency of the transformer in related technologies is solved.

Description

Technical Field

[0001] The present application relates to the field of transformer testing, and in particular, to a transformer testing device and a control method thereof. Background Art

[0002] In related technologies, short-circuit testing of distribution transformers primarily utilizes three power supply methods: dedicated network power, short-circuit generator power, and energy storage power. Compared to the first two methods, the energy storage power supply method reduces the time required for routine maintenance of various equipment and simplifies the testing process.

[0003] However, in the related art, the execution of the test process in the short-circuit test operation method relies on the manual judgment and operation of the detection technician. After each short-circuit test is completed, the personnel are required to connect the impedance tester wiring after grounding and discharging the transformer to be tested, and switch the transformer gear to carry out the impedance test of the transformer. The operation process is cumbersome, the test efficiency is low, and frequent wiring can easily lead to human error operations.

[0004] Currently, no effective solution has been proposed to the problem of low transformer detection efficiency in related technologies. Summary of the Invention

[0005] The main purpose of this application is to provide a transformer testing device and a control method thereof to solve the problem of low transformer detection efficiency in related technologies.

[0006] In order to achieve the above objectives, according to one aspect of the present application, a transformer testing device is provided. The device includes: an energy storage unit for storing electric energy required for a short-circuit test; an inverter unit, the input side of which is connected to the energy storage unit and the output side of which is connected to a transformer to be tested, for outputting a voltage during a short-circuit test; a switching switch, comprising two groups of switches, wherein when the first group of switches is closed and the second group of switches is disconnected, the device is used to measure the impedance value of the transformer to be tested, and when the first group of switches is disconnected and the second group of switches is closed, the device is used to perform a short-circuit test; an impedance measuring unit, connected to the first group of switches and connected to the transformer to be tested when the first group of switches is closed, for measuring the impedance value of the transformer to be tested; a transformer to be tested, connected to the switching switch and connected to the impedance measuring unit when the first group of switches is closed for measuring the impedance value, and connected to the inverter unit when the second group of switches is closed for performing a short-circuit test; and a control unit, connected to the energy storage unit, the inverter unit, the switching switch, the impedance measuring unit and the transformer to be tested, for controlling the energy storage unit to discharge, controlling the inverter unit to output voltages at different phases, controlling the switching switch to switch between an impedance measurement circuit and a short-circuit test circuit, controlling the impedance measurement unit to measure impedance values ​​at different phases, and controlling the transformer to be tested to adjust a voltage level.

[0007] Optionally, the transformer testing device further includes: an AC power grid for outputting three-phase AC power; and a charging unit, the input side of which is connected to the AC power grid and the output side of which is connected to the energy storage unit, for charging the energy storage unit.

[0008] Optionally, the transformer testing device also includes: a gear switching device, connected to the control unit and the transformer to be tested, for receiving a voltage gear adjustment instruction from the control unit to control the transformer to be tested to adjust the voltage gear; a deformation testing device, connected to the control unit and the transformer to be tested, for receiving a deformation test instruction from the control unit to test whether the transformer to be tested is deformed.

[0009] Optionally, the control unit controls the impedance measurement unit to measure the impedance values ​​of different phases, including: the control unit controls the gear switching device to adjust the voltage gear to the first voltage gear, determines the first phase corresponding to the first voltage gear, and controls the impedance measurement unit to measure the first initial impedance value of the first phase of the transformer to be detected; the control unit controls the gear switching device to adjust the voltage gear to the second voltage gear, determines the second phase corresponding to the second voltage gear, and controls the impedance measurement unit to measure the second initial impedance value of the second phase of the transformer to be detected, wherein the voltage of the second voltage gear is lower than the voltage of the first voltage gear; the control unit controls the gear switching device to adjust the voltage gear to the third voltage gear, determines the third phase corresponding to the third voltage gear, and controls the impedance measurement unit to measure the third initial impedance value of the third phase of the transformer to be detected, wherein the voltage of the third voltage gear is lower than the voltage of the second voltage gear.

[0010] Optionally, the control unit controls the switching switch to adjust the impedance test circuit to a short-circuit test circuit; connects a load to the short-circuit test circuit when the AC voltage is in the target phase to perform a short-circuit test on the transformer to be tested at the target phase; obtains the test voltage and test current of the transformer to be tested, and the control unit determines the test result of the short-circuit test of the transformer to be tested in the target phase based on the test voltage and test current.

[0011] Optionally, the control unit determines the test result of the short-circuit test of the transformer to be tested in the target phase based on the test voltage and the test current, including: judging whether there is any abnormality in the waveforms of the test voltage and the test current, judging whether the test voltage belongs to a preset voltage range, and judging whether the test current belongs to a preset current range; when there is no abnormality in the waveforms of the test voltage and the test current, the test voltage belongs to the preset voltage range, and the test current belongs to the preset current range, the test result is determined to be a successful test; when there is an abnormality in the waveform of the test voltage or the test current, or the test voltage does not belong to the preset voltage range, or the test current does not belong to the preset current range, the test result is determined to be a failed test.

[0012] Optionally, when the test result of the short-circuit test of the target phase is a success, the control unit controls the switching switch to adjust the short-circuit test circuit to an impedance test circuit, and controls the impedance measurement unit to collect the impedance value of the transformer to be tested after the short-circuit test at the target phase, to obtain a test impedance value; when the test result of the short-circuit test of the target phase is a failure, it is determined that the test of the transformer to be tested is unqualified.

[0013] Optionally, the deformation testing device is controlled to test whether the transformer to be tested is deformed; if the transformer to be tested is deformed, the transformer to be tested is determined to be unqualified; if the transformer to be tested is not deformed, the transformer to be tested is determined to be qualified.

[0014] Optionally, the control unit calculates the impedance change rate of the phase based on the initial impedance value and the test impedance value of each phase; when the impedance change rate of all phases is less than the change rate threshold, it is determined that the detection of the transformer to be detected is qualified; when the impedance change rate of any phase is greater than or equal to the change rate threshold, it is determined that the detection of the transformer to be detected is unqualified.

[0015] According to another aspect of the present application, a control method for a transformer testing device is also provided. The method includes: obtaining target parameters of the transformer to be tested, determining the test voltage and test current of the transformer to be tested based on the target parameters, and loading the test voltage and test current on the transformer testing device, wherein the target parameters include at least one of the following: rated capacity, rated voltage level, and phase sequence; controlling the first group of switches in the switching switches of the transformer testing device to be closed and the second group of switches to be opened, controlling the gear switching device to switch the voltage gear, and measuring the initial impedance value of the phase corresponding to the voltage gear of the transformer to be tested through the impedance measurement unit after each voltage gear switch; after obtaining the initial impedance values ​​of all phases, controlling the first group of switches in the switching switches to be closed and the second group of switches to be opened, and controlling the gear switching device to switch the voltage gear. The switch is disconnected, the second set of switches is closed, and the gear switching device is controlled to switch the voltage gear. After each switching of the voltage gear, the impedance value of the transformer to be tested after the short-circuit test is performed at the target phase is measured by the impedance measurement unit to obtain the test impedance value, wherein the target phase is the phase corresponding to the voltage gear; after obtaining the test impedance values ​​of all phases, the deformation testing device is controlled to test the deformation result of the transformer to be tested. When the impedance change rate of all phases is less than the change rate threshold and the transformer to be tested is not deformed, it is determined that the transformer to be tested is qualified, wherein the impedance change rate is calculated by the initial impedance value and the test impedance value.

[0016] According to another aspect of the present application, a transformer detection method is also provided. The method includes: obtaining target parameters of the transformer to be detected, determining a test voltage and a test current of the transformer to be detected based on the target parameters, wherein the target parameters include at least one of the following: rated capacity, rated voltage level, and phase sequence; applying the test voltage and test current to a transformer test device, and measuring the initial impedance value of each phase of the transformer to be detected under three-phase alternating current by the transformer test device; for each phase of the three-phase alternating current, performing a short-circuit test on the transformer to be detected in the target phase by the transformer test device, and collecting the impedance value of the transformer to be detected after the short-circuit test in the target phase to obtain a test impedance value; calculating the impedance change rate of each phase based on the initial impedance value and the test impedance value, and determining that the transformer to be detected has passed the test if the impedance change rate of all phases is less than a change rate threshold.

[0017] To achieve the above-mentioned object, according to another aspect of the present application, a transformer detection device is provided. The device includes: an acquisition unit for acquiring target parameters of the transformer to be detected, and determining a test voltage and a test current of the transformer to be detected based on the target parameters, wherein the target parameters include at least one of the following: rated capacity, rated voltage level, and phase sequence; a loading unit for loading the test voltage and the test current on the transformer test device, and measuring the initial impedance value of each phase of the transformer to be detected under three-phase alternating current through the transformer test device; a testing unit for performing a short-circuit test on the transformer to be detected in the target phase for each phase under three-phase alternating current through the transformer test device, and collecting the impedance value of the transformer to be detected after the short-circuit test in the target phase to obtain a test impedance value; and a calculation unit for calculating the impedance change rate of each phase based on the initial impedance value and the test impedance value, and determining that the transformer to be detected has passed the test when the impedance change rate of all phases is less than a change rate threshold.

[0018] In order to achieve the above-mentioned object, according to another aspect of the present application, a computer program product is provided, comprising a computer program, which, when executed by a processor, implements the steps of the transformer detection method described in each embodiment of the present application.

[0019] The present application adopts the following devices: an energy storage unit for storing the electric energy required for the short-circuit test; an inverter unit, the input side of which is connected to the energy storage unit, and the output side of which is connected to the transformer to be tested, for outputting the voltage during the short-circuit test; a switching switch, comprising two groups of switches, wherein the first group of switches is closed and the second group of switches is disconnected, for measuring the impedance value of the transformer to be tested; and the first group of switches is disconnected and the second group of switches is closed, for performing the short-circuit test; an impedance measuring unit, connected to the first group of switches, and connected to the transformer to be tested when the first group of switches is closed, for measuring the impedance value of the transformer to be tested; the transformer to be tested is connected to the The switching switch is connected to the impedance measurement unit when the first set of switches is closed, for measuring impedance values. When the second set of switches is closed, it is connected to the inverter unit for performing a short-circuit test. The control unit is connected to the energy storage unit, the inverter unit, the switching switch, the impedance measurement unit, and the transformer to be tested. It is used to control the discharge of the energy storage unit, control the inverter unit to output voltage at different phases, control the switching switch to switch between the impedance measurement circuit and the short-circuit test circuit, control the impedance measurement unit to measure impedance values ​​at different phases, and control the transformer to be tested to adjust the voltage level. This solves the problem of low transformer testing efficiency in related technologies. The transformer testing device automatically performs short-circuit testing and impedance measurement on the transformer to be tested, eliminating the need for manual operation of the switching circuit process, thereby achieving the effect of improving transformer testing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. In the accompanying drawings:

[0021] Figure 1 is a structural diagram of a transformer testing device provided according to an embodiment of the present application;

[0022] Figure 2 is a flow chart of a control method for a transformer testing device provided in an embodiment of the present application;

[0023] Figure 3 is a flow chart of a transformer detection method provided according to an embodiment of the present application;

[0024] Figure 4 is a schematic diagram of an optional transformer detection method provided according to an embodiment of the present application;

[0025] Figure 5 is a schematic diagram of a transformer detection device provided according to an embodiment of the present application;

[0026] Figure 6 is a schematic diagram of an electronic device provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0027] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0028] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0029] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0030] The present invention is described below in conjunction with preferred implementation steps. According to an embodiment of the present application, a transformer testing device is provided. Figure 1 Schematic diagram of the structure of the transformer testing device provided in accordance with an embodiment of the present application. Figure 1 As shown, the device includes:

[0031] Energy storage unit, used to store the electrical energy required for short-circuit test.

[0032] Specifically, the energy storage unit may include a capacitor module, which connects the charging unit and the inverter unit and is used to store the electrical energy required for the short-circuit withstand capacity test. The energy storage unit can be assembled using a supercapacitor or a conventional electrolytic capacitor module. The specific capacity and selection are determined according to the specific test requirements. Each capacitor module is equipped with a monitoring module to monitor the abnormal status of the capacitor in real time.

[0033] The inverter unit has an input side connected to the energy storage unit and an output side connected to the transformer to be tested, and is used for voltage output during short-circuit testing.

[0034] Specifically, the inverter unit can adopt a full-bridge circuit to achieve voltage output through phase shift control. The same number of inverter units as the capacitor modules are used, and the output side adopts a series output method to achieve high voltage output on the transformer side.

[0035] The switching switch includes two groups of switches. When the first group of switches is closed and the second group of switches is disconnected, it is used to measure the impedance value of the transformer to be detected. When the first group of switches is disconnected and the second group of switches is closed, it is used to perform a short-circuit test.

[0036] Specifically, the switching switch may include two groups of interlocking switches, A and B. Group A switches are also the first group of switches, and group B switches are also the second group of switches. The two groups of switches cannot be in the closed state at the same time. When the group A switches are closed, the group B switches are disconnected, and the impedance value of the distribution transformer is measured. When the group A switches are disconnected, the group B switches are closed, and the short-circuit withstand capacity test of the distribution transformer is performed. When both groups A and B switches are in the disconnected state, the transformer testing device is in standby state.

[0037] The impedance measuring unit is connected to the first set of switches and is connected to the transformer to be detected when the first set of switches is closed, and is used to measure the impedance value of the transformer to be detected.

[0038] Specifically, the impedance measurement unit may include an impedance test bridge, which is connected to the transformer to be tested by switching the switches in group A in the switch to achieve the measurement of the three-phase impedance value; the impedance measurement unit is used in conjunction with the switching switch, and a full-bridge impedance tester is used to test the impedance value of each phase winding of the transformer to be tested in turn.

[0039] The transformer to be tested is connected to the switching switch. When the first set of switches is closed, it is connected to the impedance measurement unit for measuring the impedance value. When the second set of switches is closed, it is connected to the inverter unit for performing a short-circuit test.

[0040] Specifically, the transformer to be tested may be a distribution transformer, and by switching switches and corresponding circuit designs in the transformer testing device, short-circuit testing and impedance measurement can be performed separately in the same device.

[0041] The control unit is connected to the energy storage unit, the inverter unit, the switching switch, the impedance measurement unit and the transformer to be tested, and is used to control the discharge of the energy storage unit, control the inverter unit to output voltage at different phases, control the switching switch to switch the impedance measurement circuit and the short-circuit test circuit, control the impedance measurement unit to measure the impedance values ​​of different phases, and control the transformer to be tested to adjust the voltage gear.

[0042] Specifically, the control unit can collect test voltage and current, and integrate built-in judgment criteria and control processes to achieve fully automated measurement of the short-circuit withstand capacity test of the transformer under test, replacing the manual wiring and testing procedures in related technologies. The control unit can also realize data collection and communication functions between other power units (charging units, energy storage units, etc.) through optical fiber communication, network port communication, or 485 communication, and has built-in judgment logic and protection logic to achieve fully automated execution of the entire short-circuit test process.

[0043] The transformer testing device provided in this embodiment can be used in distribution transformer short-circuit testing sites or high-voltage switchgear short-circuit testing sites, or in other locations or technical fields where auxiliary tests and comparisons are required before and after the main test. By adding an impedance measurement unit, a changeover switch, a gear switching device, a deformation testing device, and judgment and control logic to a traditional short-circuit test device, automated testing and judgment of transformer short-circuit withstand capacity testing is achieved, reducing the difficulty of equipment use and improving detection efficiency and intelligence.

[0044] In order to power the energy storage unit, it is also necessary to connect the AC power grid and the charging unit. Optionally, the transformer testing device also includes: an AC power grid for outputting three-phase AC power; a charging unit, the input side of which is connected to the AC power grid and the output side is connected to the energy storage unit, for charging the energy storage unit.

[0045] Specifically, the charging unit can be a bidirectional rectifier, with the input side connected to the AC power grid and the output side connected to the energy storage unit. The energy storage unit is charged before the test, and the excess energy is fed back to the power grid after the test. For example, a three-phase PWM (Pulse Width Modulation) rectifier device or a multi-level control device can be added. A multi-winding power frequency transformer or multiple high-frequency transformers can be added to isolate common-mode interference.

[0046] After the short-circuit test, it is necessary to use a deformation testing device to test whether the transformer to be tested is deformed. Optionally, the transformer testing device also includes: a gear switching device, connected to the control unit and the transformer to be tested, for receiving a voltage gear adjustment instruction from the control unit to control the transformer to be tested to adjust the voltage gear; a deformation testing device, connected to the control unit and the transformer to be tested, for receiving a deformation test instruction from the control unit to test whether the transformer to be tested is deformed.

[0047] Specifically, the gear switching device is used to remotely switch the high, medium, and low voltage gears of the transformer under test. The medium voltage gear can be the rated voltage of the transformer under test, the high voltage gear can be a voltage that is a preset percentage higher than the rated voltage, and the low voltage gear can be a voltage that is a preset percentage lower than the rated voltage. The gear switching device can include a small motor and its control device. By being attached to the gear switching switch of the transformer under test, the transformer gear is switched via a remote control signal. A built-in adjustable fixture is used to match the gear switching switches of different models and types of transformers.

[0048] The deformation testing device can use equipment such as laser testers to test whether the transformer windings and body are deformed before and after short circuit. The deformation testing device uses the principle of laser ranging and is installed around the transformer specimen before the test begins. After the short circuit test, if the transformer windings and body are deformed, the deformation condition can be effectively tested to assist in determining the conclusion of the short circuit test.

[0049] The voltage gear is adjusted by the gear switching device to measure the initial impedance values ​​of different phases. Optionally, in the transformer testing device provided in the embodiment of the present application, the control unit controls the impedance measurement unit to measure the impedance values ​​of different phases, including: the control unit controls the gear switching device to adjust the voltage gear to the first voltage gear, determines the first phase corresponding to the first voltage gear, and controls the impedance measurement unit to measure the first initial impedance value of the first phase of the transformer to be tested; the control unit controls the gear switching device to adjust the voltage gear to the second voltage gear, determines the second phase corresponding to the second voltage gear, and controls the impedance measurement unit to measure the second initial impedance value of the second phase of the transformer to be tested, wherein the voltage of the second voltage gear is lower than the voltage of the first voltage gear; the control unit controls the gear switching device to adjust the voltage gear to the third voltage gear, determines the third phase corresponding to the third voltage gear, and controls the impedance measurement unit to measure the third initial impedance value of the third phase of the transformer to be tested, wherein the voltage of the third voltage gear is lower than the voltage of the second voltage gear.

[0050] In some examples, the control unit adjusts the gear switching device of the transformer testing device to the first voltage gear, i.e., the highest operating voltage gear of the transformer, determines the first phase corresponding to the first voltage gear, such as phase A, and ensures that the testing device is correctly connected to the winding of that phase. After the connection and setup are completed, the impedance measurement unit begins measuring the initial impedance value of phase A at the first voltage gear, i.e., the first initial impedance value. The initial impedance value is used to reflect the impedance characteristics of the transformer under test before undergoing a short-circuit test.

[0051] Next, the control unit adjusts the gear switching device of the transformer testing device to a second voltage gear, which is lower than the voltage of the first voltage gear, and determines a second phase corresponding to the second voltage gear, such as phase B. The initial impedance value of phase B at the second voltage gear is measured, i.e., the second initial impedance value. The voltage gear is further adjusted to a third voltage gear, which is lower than the voltage of the second voltage gear, and the impedance performance of the transformer is tested again. A third phase corresponding to the third voltage gear is determined, such as phase C, and the initial impedance value of phase C at the third voltage gear is measured, i.e., the third initial impedance value.

[0052] This embodiment ensures that each phase of the transformer can be fully evaluated under different voltage conditions. The control unit automates this process by adjusting the voltage range and selecting the correct phase, reducing the complexity and potential errors of manual operation. The impedance measurement unit accurately measures the initial impedance of the transformer winding at each phase and voltage range to assess the transformer's compliance.

[0053] A short-circuit test is performed after measuring the initial impedance value. Optionally, in the transformer testing device provided in the embodiment of the present application, the control unit controls the switching switch to adjust the impedance test circuit to a short-circuit test circuit; a load is connected to the short-circuit test circuit when the AC voltage is in the target phase to perform a short-circuit test on the transformer to be tested at the target phase; the test voltage and test current of the transformer to be tested are obtained, and the control unit determines the test result of the short-circuit test of the transformer to be tested in the target phase based on the test voltage and test current.

[0054] In some examples, the control unit switches the transformer test device from an impedance test mode to a short-circuit test mode. By changing the state of the switch, the connection to the impedance measurement unit is disconnected, and the connection to the inverter unit is closed, preparing to apply the high voltage required for the short-circuit test. When the short-circuit test circuit is ready, the control unit connects the load when the AC voltage is at the target phase and starts the short-circuit test. During the short-circuit test, the control unit collects test voltage and test current data in real time. Based on the collected test voltage and current data and the rated parameters of the transformer, the control unit calculates the test results. After completing the short-circuit test of one phase, the control unit automatically switches the test device back to the impedance test mode and remeasures the impedance value to evaluate the performance changes of the transformer after the short-circuit test. Then, this process is repeated to perform the same test on phases B and C to ensure a comprehensive evaluation of the three-phase transformer.

[0055] The entire short-circuit test process of this embodiment is automatically controlled by the control unit, which ensures the consistency and safety of the test and improves the efficiency of the short-circuit test.

[0056] Optionally, in the transformer testing device provided in the embodiment of the present application, the control unit determines the test result of the short-circuit test of the transformer to be tested in the target phase based on the test voltage and the test current, including: judging whether there is an abnormality in the waveform of the test voltage and the test current, judging whether the test voltage belongs to a preset voltage range, and judging whether the test current belongs to a preset current range; when there is no abnormality in the waveform of the test voltage and the test current, the test voltage belongs to the preset voltage range, and the test current belongs to the preset current range, the test result is determined to be a successful test; when there is an abnormality in the waveform of the test voltage or the test current, or the test voltage does not belong to the preset voltage range, or the test current does not belong to the preset current range, the test result is determined to be a failed test.

[0057] In some examples, the control unit continuously monitors the waveforms of the test voltage and current. During a short-circuit test, the voltage rapidly drops to almost zero, while the current rapidly rises to the short-circuit current level. Any waveform deviation from expected behavior, such as unexpected peaks in the voltage waveform or discontinuities or oscillations in the current waveform, indicates an anomaly during the short-circuit test. If an anomaly is detected, the control unit immediately interrupts the test to prevent further damage and marks the test result as a failure.

[0058] The preset voltage range is determined based on the transformer's rated voltage and short-circuit test standards. If the test voltage exceeds this range, either too high or too low, the test is considered a failure. Similarly, the control unit monitors whether the test current is within a preset current range. The preset current range is based on the transformer's rated current. If the test current exceeds this range, the test is considered a failure.

[0059] If the waveforms of the test voltage and current are normal during the short-circuit test and are within the preset voltage and current ranges, the control unit will determine that the short-circuit test is successful. This indicates that the transformer under test can withstand the short-circuit condition at the target phase without exhibiting unexpected behavior.

[0060] Through automated control and real-time data analysis, the control unit in this embodiment ensures the accuracy and safety of short-circuit tests while significantly improving test efficiency. This ensures a comprehensive and accurate assessment of the transformer's short-circuit withstand capacity, providing a reliable basis for stable grid operation and maintenance decisions.

[0061] After determining the test result, it is determined whether to measure the impedance value based on the test result. Optionally, in the transformer testing device provided in the embodiment of the present application, when the test result of the short-circuit test of the target phase is a successful test, the control unit controls the switching switch to adjust the short-circuit test circuit to an impedance test circuit, and controls the impedance measurement unit to collect the impedance value of the transformer to be tested after the short-circuit test is performed at the target phase to obtain a test impedance value; when the test result of the short-circuit test of the target phase is a test failure, it is determined that the test of the transformer to be tested is unqualified.

[0062] In some examples, if the test result is successful, the control unit switches the switch from short-circuit test mode to impedance measurement mode and reconnects the impedance test unit to the corresponding phase of the transformer to be tested. The control unit then controls the impedance measurement unit to begin measuring the impedance value of the target phase after the short-circuit test. The impedance tester applies a low-voltage signal and measures the corresponding current to calculate the test impedance value.

[0063] If the short-circuit test on the target phase is judged to have failed, it means that an abnormal voltage or current was detected during the test, or that it was outside the preset range. This indicates that the transformer has serious safety problems or performance defects and cannot withstand the expected short-circuit conditions. The control unit determines that the transformer under test has failed the test.

[0064] This embodiment improves test efficiency and accuracy, ensures the safety of the test process, and reduces test costs by applying an automated measurement and control process to the short-circuit withstand capacity test of a distribution transformer.

[0065] After determining whether the transformer to be tested is qualified based on the impedance change rate, it is also necessary to detect whether the transformer to be tested is deformed. Optionally, in the transformer testing device provided in the embodiment of the present application, the deformation testing device is controlled to test whether the transformer to be tested is deformed; if the transformer to be tested is deformed, it is determined that the transformer to be tested is unqualified; if the transformer to be tested is not deformed, it is determined that the transformer to be tested is qualified.

[0066] In some examples, after the short-circuit test and impedance measurement, the deformation test device is activated. A laser rangefinder or other precision measuring tool is pre-positioned around the transformer to be tested, allowing for dimensional measurements of key locations before and after the test. The control unit activates the deformation test device and begins multi-point measurement of key transformer components, such as the windings, core, and casing.

[0067] The measurement data collected by the deformation test device is transmitted to the control unit for analysis. The control unit compares the dimensions of each measurement point before and after the short-circuit test to determine whether deformation has occurred. If the deformation values ​​of all measurement points are less than the preset deformation threshold, the control unit will determine that the transformer to be tested has not been structurally deformed, which indicates that the transformer can withstand the mechanical stress generated by the short-circuit test and the physical structure remains intact. Therefore, the transformer to be tested can be judged to be qualified. On the contrary, if the deformation value of any measurement point exceeds the deformation threshold, this indicates that some parts of the transformer have been damaged during the short-circuit test, such as winding displacement, core deformation or casing cracking. It is determined that the transformer to be tested is unqualified and requires further inspection and possible repair or replacement.

[0068] This embodiment uses deformation testing to comprehensively assess the physical condition of the transformer after a short-circuit test, preventing potential operational failures and ensuring grid safety. The automated control process ensures the efficiency and accuracy of deformation testing, reduces human error, and provides reliable test results.

[0069] If the impedance change rate of any phase is greater than or equal to the change rate threshold, the transformer to be tested is determined to be unqualified. Optionally, in the transformer testing device provided in the embodiment of the present application, the control unit calculates the impedance change rate of the phase based on the initial impedance value and the test impedance value of each phase; when the impedance change rate of all phases is less than the change rate threshold, it is determined that the test of the transformer to be tested is qualified; when the impedance change rate of any phase is greater than or equal to the change rate threshold, it is determined that the test of the transformer to be tested is unqualified.

[0070] In some examples, the control unit calculates the corresponding impedance change rate based on the impedance measurement values ​​of each phase before and after the short-circuit test. The control unit compares the calculated impedance change rate with a preset change rate threshold. If the impedance change rate of all phases is less than the change rate threshold, it indicates that the transformer under test has not suffered significant damage during the short-circuit test and is considered qualified.

[0071] If the impedance change rate of any phase is greater than or equal to the change rate threshold, it means that the winding or the internal structure of the transformer has undergone irreversible deformation or damage. The control unit will mark the detection result of the phase as unqualified, which means that the transformer to be tested is unqualified.

[0072] In this embodiment, by determining whether the transformer to be tested is qualified based on the impedance change rate, the control unit can accurately evaluate the performance status of the distribution transformer after the short-circuit withstand capacity test, thereby ensuring the safety and reliability of the power grid equipment.

[0073] According to another embodiment of the present application, a control method for a transformer testing device is provided. Figure 2is a flow chart of a control method for a transformer testing device according to an embodiment of the present application. Figure 2 As shown, the method includes the following steps:

[0074] Step S201, obtaining target parameters of the transformer to be tested, determining a test voltage and a test current of the transformer to be tested based on the target parameters, and applying the test voltage and the test current to a transformer testing device, wherein the target parameters include at least one of the following: rated capacity, rated voltage level, and phase sequence;

[0075] Step S202: Controlling the first set of switches in the transformer testing device to close and the second set of switches to open, controlling the gear switching device to switch the voltage gear, and measuring the initial impedance value of the phase corresponding to the voltage gear of the transformer to be tested by the impedance measurement unit after each voltage gear switch;

[0076] Step S203: After obtaining the initial impedance values ​​of all phases, the first set of switches in the switching switch is controlled to be open and the second set of switches is controlled to be closed, and the gear switching device is controlled to switch the voltage gear. After each voltage gear switch, the impedance value of the transformer to be tested after the short-circuit test is performed at the target phase is measured by the impedance measurement unit to obtain a test impedance value, wherein the target phase is the phase corresponding to the voltage gear.

[0077] Step S204: After obtaining the test impedance values ​​of all phases, control the deformation testing device to test the deformation results of the transformer to be tested. If the impedance change rate of all phases is less than the change rate threshold and the transformer to be tested is not deformed, it is determined that the transformer to be tested is qualified, wherein the impedance change rate is calculated by the initial impedance value and the test impedance value.

[0078] This embodiment uses a control method for a transformer testing device to automatically perform short-circuit testing and impedance measurement on the transformer to be tested on the same transformer testing device, saving the process of manually operating circuit switching, thereby achieving the effect of improving transformer testing efficiency.

[0079] According to another embodiment of the present application, a transformer detection method using a transformer testing device is provided. Figure 3 is a flow chart of a transformer detection method provided in accordance with an embodiment of the present application, such as Figure 3 As shown, the method includes the following steps:

[0080] Step S301: Obtain target parameters of the transformer to be tested, and determine the test voltage and test current of the transformer to be tested based on the target parameters, wherein the target parameters include at least one of the following: rated capacity, rated voltage level, and phase sequence.

[0081] In step S301, the rated capacity refers to the power that the transformer can continuously transmit under normal operating conditions, measured in kVA (kilovolt-amperes). The rated voltage class refers to the rated voltage of the transformer's primary and secondary windings, typically measured in kV (kilovolts), and is used to determine the voltage level during the test. The phase sequence determines the order of phases in a three-phase transformer, ensuring that the phase of the test voltage matches the phase of the transformer.

[0082] The upper and lower limits of the test voltage are determined based on the transformer's rated voltage and the test standard. For example, for a transformer with a rated voltage of 10 kV, the test voltage needs to be adjusted to a certain percentage of the transformer's rated voltage, such as 1.1 times or less, to simulate a short-circuit condition without damaging the equipment. The test voltage also needs to take the transformer's phase sequence into account, ensuring that the voltage is applied in the correct phase sequence to avoid interphase shorts. The test current can be determined based on the transformer's rated capacity. Based on the rated capacity and rated voltage, the rated current of the transformer under full load can be calculated. For example, a three-phase transformer with a rated capacity of 1000 kVA and a rated voltage of 10 kV has a rated current of approximately 57.7 A.

[0083] During a short-circuit test, the test current is significantly greater than the rated current, but must be kept within a safe range to avoid irreversible damage to the transformer or test equipment. The test current can range from several to dozens times the rated current of the transformer, depending on the type and design of the transformer. The relationship between the test voltage and test current must adhere to Ohm's law, taking into account the transformer's impedance and the specific test objectives, such as testing the transformer's short-circuit withstand capability or detecting winding deformation.

[0084] Step S302: A test voltage and a test current are applied to the transformer test device, and the initial impedance value of each phase of the transformer to be tested under three-phase alternating current is measured by the transformer test device.

[0085] In step S302, the transformer testing device is properly connected to the transformer to be tested, ensuring that the primary winding of each phase is connected to the corresponding phase of the testing device. At the same time, all safety measures are in place, including grounding, disconnecting non-test phases, and setting up protective fencing. Based on the rated voltage and rated capacity of the transformer, the control unit is used to set the output parameters of the inverter unit, including the output voltage and frequency, as well as the expected test current.

[0086] After applying the test voltage and test current, the impedance measurement unit is used to measure the initial impedance value of each phase of the transformer. Impedance measurements can be performed at low voltage to avoid generating unnecessary heat or stress. The impedance measurement unit calculates the initial impedance value of each phase by monitoring the input voltage and current, as well as the output voltage and current. The control unit records the initial impedance value of each phase. After completing the impedance measurement of phase A, the control unit switches the gear switching device to change the voltage gear of the transformer to be tested, and the same impedance measurement is performed on phases B and C in sequence to ensure comprehensive testing of the three-phase impedance.

[0087] Step S303 : For each phase of the three-phase AC power, a short-circuit test is performed on the transformer to be tested in the target phase by a transformer testing device, and the impedance value of the transformer to be tested after the short-circuit test in the target phase is collected to obtain a test impedance value.

[0088] In step S303, for each target phase, the inverter unit is connected to the winding of the target phase, ensuring that the energy storage unit is fully charged, and the switch is set to the short-circuit test mode. At the same time, the control unit checks the safety status of the equipment to ensure that the winding of the non-target phase is disconnected or short-circuited to avoid interference. The control unit starts the inverter unit and applies the short-circuit test voltage to the winding of the target phase according to the test voltage and test current parameters. The transformer test device will accurately control the voltage rise rate and final value to meet the test standards and safety requirements. While applying the short-circuit test voltage, the control unit monitors the changes in voltage and current in real time to ensure that the test process is within a safe range.

[0089] During the short-circuit test, the control unit records the voltage and current curves using a data acquisition system. Upon completion of the test, the control unit immediately disconnects the inverter unit's output and connects the impedance measurement unit to the target phase's winding via a switch. Within the safety period following the short-circuit test, the impedance measurement unit performs impedance measurements on the target phase's winding. The impedance value obtained from this measurement serves as the test impedance value for the target phase. After completing the short-circuit test and impedance measurement of phase A, the control unit switches to phases B and C via the gear shifter and repeats the process. This ensures that all phases of the three-phase transformer are fully tested.

[0090] Step S304 , calculating the impedance change rate of each phase based on the initial impedance value and the test impedance value, and determining that the transformer to be tested has passed the test when the impedance change rates of all phases are less than a change rate threshold.

[0091] In step S304, after calculating the impedance change rate for each phase based on the initial impedance value and the test impedance value, the impedance change rate is compared with a pre-set change rate threshold. The change rate threshold can be determined based on the transformer's design specifications, material properties, and relevant standards. If the impedance change rate for all phases is less than the threshold, it can be preliminarily determined that the short-circuit withstand capacity of the transformer under test meets the requirements, meaning the test has passed. If the impedance change rate for any phase exceeds the threshold, the transformer under test is determined to have failed the test.

[0092] The transformer detection method provided by the embodiment of the present application obtains the target parameters of the transformer to be detected, determines the test voltage and test current of the transformer to be detected based on the target parameters, wherein the target parameters include at least one of the following: rated capacity, rated voltage level and phase sequence; loads the test voltage and test current on the transformer test device, and measures the initial impedance value of each phase of the transformer to be detected under three-phase alternating current through the transformer test device; for each phase under three-phase alternating current, performs a short-circuit test on the transformer to be detected in the target phase through the transformer test device, and collects the impedance value of the transformer to be detected after the short-circuit test in the target phase to obtain a test impedance value; calculates the impedance change rate of each phase based on the initial impedance value and the test impedance value, and determines that the transformer to be detected is qualified when the impedance change rate of all phases is less than the change rate threshold, thereby solving the problem of low transformer detection efficiency in the related art. By automatically performing short-circuit testing and impedance measurement on the transformer to be detected through the transformer test device, the process of manually operating the switching circuit is saved, thereby achieving the effect of improving transformer detection efficiency.

[0093] According to another embodiment of the present application, an optional transformer detection method using a transformer testing device is also provided. Figure 4 Schematic diagram of an optional transformer detection method provided according to an embodiment of the present application. Figure 4 As shown, the method includes: inputting the parameters of the test product (that is, the transformer to be tested), starting the charging process of the transformer testing device, determining whether the voltage of the energy storage unit has reached the required value, and continuing the charging process if it has not reached the required value; if it has reached the required value, stopping the charging process. Adjust the voltage gear through the gear switching device, and test the initial three-phase impedance value of the phase corresponding to each voltage gear respectively, test each phase three times, and test all phases nine times in total. Determine whether the initial three-phase impedance test is completed before the short-circuit test. If not, continue the test. If the test is completed, disconnect the group A switching switch of the transformer testing device and close the group B switching switch. Start the inverter unit to implement the option operation, perform a short-circuit test on the transformer phase A once, and the control unit collects the test data and makes a comprehensive judgment on the short-circuit test voltage and current.

[0094] If the test voltage and current do not meet the standard requirements, the test is terminated. If they do meet the standard requirements, disconnect the switch of group B and close the switch of group A. Measure the impedance value after the short-circuit test of phase A. Determine whether the impedance value after the short circuit meets the standard requirements. If not, the test is terminated. If it does, determine whether this short-circuit test is the third test. If not, repeat the short-circuit test of phase A until the test is completed three times. After completing three short-circuit tests on phase A, switch the voltage gear of the gear switching device, and then perform three short-circuit tests on phase B in the same steps. Similarly, perform three short-circuit tests on phase C. If the three short-circuit tests of each of the three phases are completed, start the deformation test device to determine whether the transformer to be tested is deformed. If deformation occurs, the test is terminated. If no deformation occurs, the test is completed. Disconnect the switch of group A and disconnect the switch of group B. Start the charging unit to feed excess energy back to the power grid.

[0095] This embodiment uses an optional transformer detection method to achieve automated testing and judgment of the transformer short-circuit withstand capacity test by adding an impedance measurement unit, a switching switch, a gear switching device, a deformation testing device, and judgment and control logic on the basis of a traditional short-circuit test device, thereby reducing the difficulty of equipment use and improving detection efficiency and intelligence.

[0096] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0097] The present application also provides a transformer detection device. It should be noted that the transformer detection device of the present application can be used to execute the transformer detection method provided in the present application. The following describes the transformer detection device provided in the present application.

[0098] Figure 5 Schematic diagram of a transformer detection device according to an embodiment of the present application. Figure 5 As shown, the device includes:

[0099] The acquisition unit 501 is used to acquire target parameters of the transformer to be detected and determine the test voltage and test current of the transformer to be detected based on the target parameters, wherein the target parameters include at least one of the following: rated capacity, rated voltage level and phase sequence.

[0100] The loading unit 502 is used to load the test voltage and test current to the transformer test device, and measure the initial impedance value of each phase of the transformer to be tested under three-phase AC power through the transformer test device.

[0101] The test unit 503 is used to perform a short-circuit test on the transformer to be tested in the target phase for each phase of the three-phase AC power through the transformer testing device, and collect the impedance value of the transformer to be tested after the short-circuit test in the target phase to obtain a test impedance value.

[0102] The calculation unit 504 is configured to calculate the impedance change rate of each phase based on the initial impedance value and the test impedance value, and determine that the transformer to be tested has passed the test when the impedance change rates of all phases are less than a change rate threshold.

[0103] The transformer detection device provided in the embodiment of the present application obtains target parameters of the transformer to be detected through an acquisition unit 501, and determines the test voltage and test current of the transformer to be detected based on the target parameters, wherein the target parameters include at least one of the following: rated capacity, rated voltage level and phase sequence; a loading unit 502 loads the test voltage and test current to the transformer test device, and measures the initial impedance value of each phase of the transformer to be detected under three-phase alternating current through the transformer test device; a testing unit 503 performs a short-circuit test on the transformer to be detected in the target phase for each phase under three-phase alternating current, and collects the impedance value of the transformer to be detected after the short-circuit test in the target phase to obtain a test impedance value; a calculation unit 504 calculates the impedance change rate of each phase based on the initial impedance value and the test impedance value, and determines that the transformer to be detected has passed the detection when the impedance change rate of all phases is less than the change rate threshold, thereby solving the problem of low transformer detection efficiency in the related art. The transformer test device automatically performs short-circuit testing and impedance measurement on the transformer to be detected, saving the process of manually operating the circuit switching, thereby achieving the effect of improving transformer detection efficiency.

[0104] Optionally, in the transformer detection device provided in the embodiment of the present application, the loading unit 502 includes: a first control module, used to control the voltage gear of the transformer testing device to be adjusted to a first voltage gear, determine the first phase corresponding to the first voltage gear, and measure the first initial impedance value of the first phase of the transformer to be detected; a second control module, used to control the voltage gear of the transformer testing device to be adjusted to a second voltage gear, determine the second phase corresponding to the second voltage gear, and measure the second initial impedance value of the second phase of the transformer to be detected, wherein the voltage of the second voltage gear is lower than the voltage of the first voltage gear; a third control module, used to control the voltage gear of the transformer testing device to be adjusted to a third voltage gear, determine the third phase corresponding to the third voltage gear, and measure the third initial impedance value of the third phase of the transformer to be detected, wherein the voltage of the third voltage gear is lower than the voltage of the second voltage gear.

[0105] Optionally, in the transformer detection device provided in the embodiment of the present application, the test unit 503 includes: a fourth control module, used to control the transformer testing device to adjust the impedance test circuit to a short-circuit test circuit; a fifth control module, used to control the transformer testing device to connect the load when the AC voltage is in the target phase, so as to perform a short-circuit test on the transformer to be tested at the target phase; an acquisition module, used to obtain the test voltage and test current of the transformer to be tested, and determine the test result of the short-circuit test of the transformer to be tested in the target phase based on the test voltage and test current.

[0106] Optionally, in the transformer detection device provided in the embodiment of the present application, the acquisition module includes: a judgment submodule, used to judge whether there is an abnormality in the waveforms of the test voltage and the test current, judge whether the test voltage belongs to the preset voltage range, and judge whether the test current belongs to the preset current range; a first determination submodule, used to determine that the test result is a successful test when there is no abnormality in the waveforms of the test voltage and the test current, the test voltage belongs to the preset voltage range, and the test current belongs to the preset current range; a second determination submodule, used to determine that the test result is a failed test when there is an abnormality in the waveform of the test voltage or the test current, or the test voltage does not belong to the preset voltage range, or the test current does not belong to the preset current range.

[0107] Optionally, in the transformer detection device provided in the embodiment of the present application, the device also includes: an execution unit, which is used to execute the step of collecting the impedance value of the transformer to be detected after the short-circuit test is performed in the target phase when the test result of the short-circuit test of the target phase is a success; and a first determination unit, which is used to determine that the detection of the transformer to be detected is unqualified when the test result of the short-circuit test of the target phase is a failure.

[0108] Optionally, in the transformer detection device provided in the embodiment of the present application, the device also includes: a testing unit, used to test whether the transformer to be detected is deformed through a deformation testing device; a second determination unit, used to determine that the transformer to be detected is unqualified when the transformer to be detected is deformed; and a third determination unit, used to determine that the transformer to be detected is qualified when the transformer to be detected is not deformed.

[0109] Optionally, in the transformer detection device provided in an embodiment of the present application, the device further includes: a fourth determination unit, configured to determine that the detection of the transformer to be detected is unqualified if the impedance change rate of any phase is greater than or equal to a change rate threshold.

[0110] The transformer detection device includes a processor and a memory. The acquisition unit 501, loading unit 502, test unit 503 and calculation unit 504 are all stored in the memory as program units. The processor executes the program units stored in the memory to implement corresponding functions.

[0111] The processor contains a kernel, which retrieves the corresponding program unit from the memory. One or more kernels can be set, and the efficiency of transformer detection can be improved by adjusting the kernel parameters.

[0112] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0113] An embodiment of the present invention provides a computer-readable storage medium having a program stored thereon. When the program is executed by a processor, a transformer detection method is implemented.

[0114] An embodiment of the present invention provides a processor, which is used to run a program, wherein the program executes a transformer detection method when running.

[0115] Figure 6 Schematic diagram of an electronic device according to an embodiment of the present application. Figure 6 As shown, the electronic device 601 includes a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, the following steps are implemented: obtaining target parameters of the transformer to be tested, determining a test voltage and a test current of the transformer to be tested based on the target parameters, wherein the target parameters include at least one of the following: rated capacity, rated voltage level, and phase sequence; applying a test voltage and a test current to a transformer test device, and measuring the initial impedance value of each phase of the transformer to be tested under three-phase AC power by the transformer test device; for each phase under three-phase AC power, performing a short-circuit test on the transformer to be tested in the target phase by the transformer test device, and collecting the impedance value of the transformer to be tested after the short-circuit test in the target phase to obtain a test impedance value; calculating the impedance change rate of each phase based on the initial impedance value and the test impedance value, and determining that the transformer to be tested has passed the test when the impedance change rate of all phases is less than a change rate threshold. The device herein can be a server, a PC, a PAD, a mobile phone, etc.

[0116] The present application also provides a computer program product, which, when executed on a data processing device, is suitable for executing an initialization program having the following method steps: obtaining target parameters of a transformer to be detected, determining a test voltage and a test current of the transformer to be detected based on the target parameters, wherein the target parameters include at least one of the following: rated capacity, rated voltage level and phase sequence; loading a test voltage and a test current on a transformer testing device, and measuring the initial impedance value of each phase of the transformer to be detected under three-phase alternating current through the transformer testing device; for each phase under three-phase alternating current, performing a short-circuit test on the transformer to be detected in the target phase through the transformer testing device, and collecting the impedance value of the transformer to be detected after the short-circuit test in the target phase to obtain a test impedance value; calculating the impedance change rate of each phase based on the initial impedance value and the test impedance value, and determining that the transformer to be detected has passed the test when the impedance change rate of all phases is less than a change rate threshold.

[0117] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0118] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0119] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0120] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0121] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0122] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0123] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0124] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0125] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0126] The above are merely embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A transformer testing device, characterized in that: include: Energy storage unit, used to store the electrical energy required for short-circuit testing; An inverter unit, the input side of which is connected to the energy storage unit, and the output side of which is connected to the transformer to be tested, for voltage output during a short-circuit test; A switching switch, comprising two sets of switches, wherein when the first set of switches is closed and the second set of switches is open, the switching switch is used to measure the impedance value of the transformer to be tested; and when the first set of switches is open and the second set of switches is closed, the switching switch is used to perform a short-circuit test; an impedance measuring unit, connected to the first set of switches and connected to the transformer to be detected when the first set of switches is closed, for measuring the impedance value of the transformer to be detected; The transformer to be tested is connected to the switching switch, and when the first set of switches is closed, is connected to the impedance measurement unit for measuring the impedance value, and when the second set of switches is closed, is connected to the inverter unit for performing a short-circuit test; A control unit is connected to the energy storage unit, the inverter unit, the switching switch, the impedance measurement unit and the transformer to be tested, and is used to control the discharge of the energy storage unit, control the inverter unit to output voltage at different phases, control the switching switch to switch the impedance measurement circuit and the short-circuit test circuit, control the impedance measurement unit to measure impedance values ​​at different phases, and control the transformer to be tested to adjust the voltage level.

2. The device according to claim 1, characterized in that The transformer testing device further comprises: A charging unit, whose input side is connected to the AC power grid and whose output side is connected to the energy storage unit, is used to charge the energy storage unit.

3. The device according to claim 1, characterized in that The transformer testing device further comprises: a gear switching device connected to the control unit and the transformer to be detected, and configured to receive a voltage gear adjustment instruction from the control unit to control the transformer to be detected to adjust the voltage gear; The deformation testing device is connected to the control unit and the transformer to be tested, and is used to receive a deformation testing instruction from the control unit to test whether the transformer to be tested is deformed.

4. The device according to claim 1, characterized in that The control unit controls the impedance measurement unit to measure impedance values ​​of different phases, including: The control unit controls the gear switching device to adjust the voltage gear to a first voltage gear, determines a first phase corresponding to the first voltage gear, and controls the impedance measurement unit to measure a first initial impedance value of the first phase of the transformer to be tested; The control unit controls the gear switching device to adjust the voltage gear to a second voltage gear, determines a second phase corresponding to the second voltage gear, and controls the impedance measurement unit to measure a second initial impedance value of the second phase of the transformer to be tested, wherein the voltage of the second voltage gear is lower than the voltage of the first voltage gear; The control unit controls the gear switching device to adjust the voltage gear to a third voltage gear, determines a third phase corresponding to the third voltage gear, and controls the impedance measurement unit to measure a third initial impedance value of the third phase of the transformer to be tested, wherein the voltage of the third voltage gear is lower than the voltage of the second voltage gear.

5. The device according to claim 1, characterized in that The control unit controls the switching switch to adjust the impedance test circuit to a short-circuit test circuit; connects a load to the short-circuit test circuit when the AC voltage is in a target phase to perform a short-circuit test on the transformer to be tested at the target phase; obtains a test voltage and a test current of the transformer to be tested, and the control unit determines a test result of the short-circuit test of the transformer to be tested in the target phase based on the test voltage and the test current.

6. The device according to claim 5, characterized in that The control unit determines a test result of a short-circuit test performed on the transformer to be tested in a target phase based on the test voltage and the test current, including: Determining whether the waveforms of the test voltage and the test current are abnormal, determining whether the test voltage falls within a preset voltage range, and determining whether the test current falls within a preset current range; If there is no abnormality in the waveforms of the test voltage and the test current, the test voltage falls within the preset voltage range, and the test current falls within the preset current range, determining that the test result is a success; When there is an abnormality in the waveform of the test voltage or the test current, or the test voltage does not fall within the preset voltage range, or the test current does not fall within the preset current range, the test result is determined to be a test failure.

7. The device according to claim 5, characterized in that When the test result of the short-circuit test of the target phase is a success, the control unit controls the switching switch to adjust the short-circuit test circuit to the impedance test circuit, and controls the impedance measurement unit to collect the impedance value of the transformer to be tested after the short-circuit test is performed at the target phase to obtain a test impedance value; when the test result of the short-circuit test of the target phase is a failure, it is determined that the test of the transformer to be tested is unqualified.

8. The device according to claim 1, characterized in that The deformation testing device is controlled to test whether the transformer to be tested is deformed; if the transformer to be tested is deformed, the transformer to be tested is determined to be unqualified; if the transformer to be tested is not deformed, the transformer to be tested is determined to be qualified.

9. The device according to claim 1, characterized in that The control unit calculates the impedance change rate of each phase based on the initial impedance value and the test impedance value of each phase; when the impedance change rate of all phases is less than the change rate threshold, it is determined that the detection of the transformer to be detected is qualified; when the impedance change rate of any phase is greater than or equal to the change rate threshold, it is determined that the detection of the transformer to be detected is unqualified.

10. A control method for a transformer testing device, applied to the transformer testing device according to any one of claims 1 to 9, characterized in that: include: Obtain target parameters of the transformer to be tested, determine a test voltage and a test current of the transformer to be tested based on the target parameters, and apply the test voltage and the test current to a transformer testing device, wherein the target parameters include at least one of the following: rated capacity, rated voltage level, and phase sequence; Controlling the first group of switches in the switching switch of the transformer testing device to be closed and the second group of switches to be open, controlling the gear switching device to switch the voltage gear, and measuring the initial impedance value of the phase of the transformer to be tested corresponding to the voltage gear through the impedance measuring unit after each voltage gear switching; After obtaining the initial impedance values ​​of all phases, controlling the first group of switches in the switching switches to be opened and the second group of switches to be closed, controlling the gear switching device to switch the voltage gear, and measuring the impedance value of the transformer to be tested after the short-circuit test is performed at the target phase by the impedance measurement unit after each voltage gear switch to obtain a test impedance value, wherein the target phase is the phase corresponding to the voltage gear; After obtaining the test impedance values ​​of all phases, the deformation testing device is controlled to test the deformation results of the transformer to be tested. When the impedance change rate of all phases is less than the change rate threshold and the transformer to be tested is not deformed, it is determined that the test of the transformer to be tested is qualified, wherein the impedance change rate is calculated by the initial impedance value and the test impedance value.

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