Automatic test system for motor protection cabinet

Abstract

The invention discloses an automatic test system for a motor protection cabinet, and relates to the technical field of electrical automatic test.The test system comprises a portable PC, a tester, a motor protection drawer cabinet, a control cable, a signal cable and a Type-C special connecting wire. Flexible configuration and automatic testing of a testing scheme are achieved, testing efficiency and accuracy are greatly improved, the system can simulate various working conditions, comprehensively test the motor protection cabinet and effectively verify various protection functions of the motor protection cabinet, meanwhile, the system has closed-loop adjustment and independent adjustment functions, testing accuracy and reliability are ensured, and the system is suitable for popularization and application. The method provides powerful support for quality control of the motor protection cabinet, and has high practical value and application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of electrical automation testing, and in particular to an automatic testing system for a motor protection cabinet. Background Art

[0002] In the current industrial automation field, motor protection cabinets are key electrical equipment, and their performance and reliability are crucial. However, traditional motor protection cabinet testing methods have many shortcomings. On the one hand, the testing process mostly relies on manual operation, the configuration of the test scheme lacks flexibility, and it is difficult to achieve comprehensive automated testing, resulting in low test efficiency and susceptibility to human factors. The test results are not accurate enough. On the other hand, traditional testing methods are difficult to simulate the complex conditions in actual working conditions, and it is impossible to fully and effectively verify the various protection functions of the motor protection cabinet. Therefore, there is an urgent need for a new type of motor protection cabinet automated testing system to solve the above problems. Summary of the invention

[0003] The purpose of the present invention is to make up for the deficiencies of the prior art and to provide an automated testing system for a motor protection cabinet. The present invention integrates a portable PC, a tester and a variety of functional modules to achieve flexible configuration and automated testing of test schemes, greatly improving test efficiency and accuracy. The system can simulate a variety of working conditions, conduct comprehensive tests on the motor protection cabinet, and effectively verify its various protection functions. At the same time, the system has closed-loop adjustment and independent adjustment functions, ensuring the accuracy and reliability of the test, providing strong support for the quality control of the motor protection cabinet, and has high practical value and application prospects.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: an automatic testing system for a motor protection cabinet, the testing system comprising:

[0005] Portable PC, used to run the host computer software and configure the test plan;

[0006] The tester communicates with the portable PC via a proprietary protocol, including:

[0007] The power supply unit adopts AC220V power supply;

[0008] The control unit, with DSP+FPGA as the core, controls the DA to output 7 analog small signals, of which 3 analog sine wave small signals 0-5VAC drive the first voltage amplifier unit to output 3 AC 150V, and another 3 analog sine wave small signals 0-5VAC drive the second voltage amplifier unit to output 3 AC 150V, and 1 0-5VDC drives the electric voltage regulator to output AC0-220V;

[0009] The first voltage amplifier unit amplifies the driving signal and outputs three-way AC 150V, which is then boosted to 100A by a current booster, and the output current is recovered through a current transformer;

[0010] The second voltage amplifier unit amplifies the driving signal and outputs 3-way AC 150V, which is then boosted to AC400V by a booster, and at the same time, voltage recovery is performed through an auxiliary tap 0-10VAC;

[0011] Electric voltage regulator drives the high-power transformer output, whose output can be switched between UA, UB, and UC output voltages and the output wiring is connected to the panel output AC0-220V;

[0012] The zero-crossing detection circuit performs zero-crossing detection on the input AC220V and outputs a reference voltage reference signal to the FPGA in the control unit;

[0013] The signal acquisition unit is used to sample 1 channel of 4-20mA DC small signal, sample 4 channels of binary input quantities through the binary input and output board, and output 6 channels of binary output quantities;

[0014] Power conversion unit, isolated output 110V / 220VDC, switched by the toggle switch on the panel;

[0015] Mabao drawer cabinet, connected to the tester, receives the voltage and current output by the tester for testing;

[0016] Control cables and signal cables are used to connect the tester and the Mabao drawer cabinet;

[0017] Type-C dedicated cable, used to connect a portable PC to the tester.

[0018] Furthermore, after the three-way AC 150V output by the first voltage amplifier unit is boosted to 100A by the current booster, the output current is recovered through the current transformer, and the recovered current signal is transmitted to the control unit for closed-loop regulation.

[0019] As a preferred solution of this embodiment, the three AC 150V output by the second voltage amplifier unit is boosted to AC400V by a booster, and then voltage is recovered through an auxiliary tap 0-10VAC, and the recovered voltage signal is transmitted to the control unit for closed-loop regulation.

[0020] As a preferred solution of this embodiment, the electric voltage regulator drives the high-power transformer output to switch between the output voltages UA, UB, and UC through software settings.

[0021] As a preferred solution of this embodiment, the host computer software has the functions of solution configuration, network configuration, connecting devices, importing solutions, starting tests, saving reports, stopping tests, device reset, AC tests, status sequence, and opening / saving reports, wherein the solution configuration is assisted by on-site testing professional technicians to complete the test solution settings for different devices and different current loops.

[0022] As a preferred solution of this embodiment, the FPGA in the control unit controls the phase of the output voltage and current according to the reference voltage reference signal output by the zero-crossing detection circuit.

[0023] As a preferred solution of this embodiment, the signal acquisition unit samples 4 channels of binary input quantities and outputs 6 channels of binary output quantities through a binary input and output board, and simultaneously samples 1 channel of 4-20mA DC small signal.

[0024] As a preferred solution of this embodiment, the power conversion unit isolates and outputs 110V / 220VDC, and switches between 110V and 220V through a toggle switch on the panel.

[0025] As a preferred solution of this embodiment, the tester simulates the instructions from the operating column and DCS, simulates the process conditions from the control system, and performs various start-stop operation tests, interlocking action parking tests, external fault parking function tests, power shake / power loss / power-on restart function tests, DO and AO signal monitoring, and overload protection, leakage protection, phase loss protection, and thermal resistance protection tests on the Mabao drawer cabinet.

[0026] As a preferred solution of this embodiment, the control unit of the tester controls the DA to output 7 analog small signals, of which 3 are used to drive the first voltage power amplifier unit to output and increase the current, 3 are used to drive the second voltage power amplifier unit to output and increase the voltage, and 1 is used to drive the electric voltage regulator output, and the voltage and current amplitude and phase of each output can be adjusted independently. The maximum output of the 3 large currents output by the first voltage power amplifier unit is up to 100A, and the output time is 30S.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) The present invention realizes comprehensive automated testing of the motor protection cabinet by integrating multiple modules such as a portable PC, a tester, a voltage amplifier unit, an electric voltage regulator, and a signal acquisition unit. Compared with the traditional testing method, the system significantly improves the testing efficiency and accuracy. The control unit of the tester is based on DSP+FPGA, which can accurately control the DA to output 7 analog small signals, and then drive the voltage amplifier unit and the electric voltage regulator to output the required voltage and current to meet various complex testing requirements. In addition, through the configuration of the upper computer software, the test plan can be flexibly set to realize customized testing of different devices and current loops, thereby improving the pertinence and practicality of the test. The application of this system reduces the labor intensity of testers, shortens the testing cycle, and provides a strong guarantee for the reliable operation of the motor protection cabinet.

[0029] (2) The present invention realizes precise control and closed-loop regulation of voltage and current during the test process. After the first voltage amplifier unit and the second voltage amplifier unit amplify and output the driving signal respectively, they are used to increase the current and voltage through the current booster and the voltage booster. At the same time, the current and voltage are recovered through the current transformer and the auxiliary tap. The recovered signals are transmitted to the control unit for closed-loop regulation. This design enables the amplitude and phase of the output voltage and current to be adjusted independently, and has high stability and accuracy. In addition, the electric voltage regulator realizes the switching of the output voltage between UA, UB, and UC through software settings, further enhancing the flexibility and adaptability of the test. The system can also simulate the instructions from the operating column and DCS, as well as the process conditions in the control system, and perform various functional tests on the motor protection cabinet, including start-stop operation test, interlocking action parking test, external fault parking function test, etc., so as to comprehensively evaluate the performance and reliability of the motor protection cabinet. The implementation of this system provides an effective testing method for the research and development and production of motor protection cabinets, which helps to improve the overall quality and market competitiveness of the product.

[0030] Other advantages, objectives and features of the present invention will be set forth in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0032] Figure 1This is a principle block diagram of an automatic test system for a motor protection cabinet;

[0033] Figure 2 The figure is a flow chart of an automatic test system for a motor protection cabinet. DETAILED DESCRIPTION

[0034] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation mode, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0035] 1. System overall architecture and connection relationship

[0036] System components:

[0037] The motor protection cabinet automatic test system of the present invention is mainly composed of a portable PC, a tester, a motor protection drawer cabinet, a control cable and a signal cable, and a Type-C dedicated connecting line.

[0038] The portable PC is used to run the host computer software and is connected to the tester via a Type-C dedicated cable to achieve control and management of the test process.

[0039] The tester is the core equipment of the test system. It is connected to the Mabao drawer cabinet through control cables and signal cables. It outputs various simulated signals to the Mabao drawer cabinet and receives its feedback signals.

[0040] Internal structure and connection of the tester:

[0041] The tester contains multiple functional units, and each unit works together. The power supply unit uses AC220V to provide power support for the entire tester.

[0042] The control unit is based on DSP+FPGA and has a close connection with other units. It controls the DA to output 7 analog small signals, of which 3 0-5VAC analog sine wave small signals drive the first voltage amplifier unit, and another 3 0-5VAC analog sine wave small signals drive the second voltage amplifier unit, and 1 0-5VDC drives the electric voltage regulator. The connection relationship is as follows: Figure 1 shown.

[0043] The first voltage amplifier unit amplifies the drive signal and outputs three AC 150V, which is then boosted to 100A by the current booster. At the same time, the output current is recovered through the current transformer and the recovered current signal is transmitted to the control unit for closed-loop regulation.

[0044] The second voltage amplifier unit amplifies the driving signal and outputs 3 AC 150V, which is then boosted to AC400V by a booster. The voltage is recovered through the auxiliary tap 0-10VAC, and the recovered voltage signal is also transmitted to the control unit for closed-loop regulation.

[0045] The electric voltage regulator drives the high-power transformer output. Its output can be switched between UA, UB, and UC output voltages and the output wiring is connected to the panel output AC0-220V. The switching function is realized through software settings and controlled by the control unit.

[0046] The zero-crossing detection circuit performs zero-crossing detection on the input AC220V and outputs a reference voltage reference signal to the FPGA in the control unit. The FPGA controls the phase of the output voltage and current according to the signal.

[0047] The signal acquisition unit is used to sample 1 channel of 4-20mA DC small signal, sample 4 channels of binary input quantities through the binary input and output board, and output 6 channels of binary output quantities at the same time.

[0048] The power conversion unit has an isolated output of 110V / 220VDC, which is switched by the toggle switch on the panel to provide appropriate DC power for different modules inside the tester.

[0049] 2. Detailed working process of each functional unit

[0050] (I) Portable PC and host computer software

[0051] Host computer software function realization:

[0052] The host computer software has many functions, such as program configuration, network configuration, connecting devices, importing programs, starting tests, saving reports, stopping tests, device reset, AC tests, status sequence, opening / saving reports, etc.

[0053] The solution configuration function is assisted by on-site testing professional technicians to complete the test solution settings for different devices and different current loops. Professional technicians set up the test solution in detail in the host computer software according to the specific model, parameters and test requirements of the Mabao drawer cabinet to be tested, including but not limited to various simulated working condition parameters, test steps, expected results, etc.

[0054] The network configuration function is used to ensure a stable communication connection between the portable PC and the tester, and to set parameters according to the actual network environment, such as IP address allocation, port number setting, etc.

[0055] The Connect Device function establishes a physical connection between the portable PC and the tester via a Type-C dedicated cable, and performs device identification and connection confirmation at the software level to ensure normal communication between the two.

[0056] The import scheme function allows users to import pre-set test schemes from external storage devices, making it easy to quickly call appropriate schemes in different test scenarios.

[0057] The start test function starts the tester to perform tests according to the preset plan. At the same time, the host computer software begins to monitor the test process in real time and collect and record relevant data.

[0058] The save report function organizes the data, test results and other information generated during the test into a report format and saves it to a specified location. The report content includes the test time, test plan details, parameter change curves during the test, test result judgment, etc.

[0059] The stop test function is used when an abnormal situation occurs during the test or when the test needs to be ended early. It can stop the tester's operation safely and orderly.

[0060] The device reset function is used to restore the tester and the Mabao drawer cabinet to their initial state after the test is completed, preparing for the next test.

[0061] The AC test function can perform specific AC signal related tests, such as simulating AC voltage fluctuations, etc., to detect the performance of the Mabao drawer cabinet under AC conditions.

[0062] The state sequence function is used to set a series of different test states and their sequences, simulating complex actual working scenarios and comprehensively testing the functions of the Mabao drawer cabinet.

[0063] The open / save report function allows users to easily view historical test reports and perform operations such as backing up and transferring reports.

[0064] (ii) Tester

[0065] Working principle of control unit:

[0066] The control unit is based on DSP+FPGA and is the control hub of the tester. It receives test instructions and configuration parameters sent by the host computer software through a private protocol, and controls the DA to output 7 analog small signals based on this information.

[0067] When controlling the voltage and current output, for the 3-channel analog sinusoidal small signals driving the first voltage power amplifier unit, the control unit performs precise calculation and adjustment so that the output signal can accurately drive the first voltage power amplifier unit to output 3 AC 150V, and performs closed-loop adjustment with the current signal collected from the current transformer to ensure the accuracy and stability of the output current. Similarly, for the 3-channel analog sinusoidal small signals driving the second voltage power amplifier unit, a similar control and adjustment process is also performed to achieve accurate voltage output and closed-loop adjustment. For the 1-channel 0-5VDC signal driving the electric voltage regulator, the electric voltage regulator is controlled to accurately switch between the UA, UB, and UC output voltages according to the output voltage switching requirements set by the software.

[0068] The FPGA accurately controls the phase of the output voltage and current based on the reference voltage reference signal output by the zero-crossing detection circuit to match the phase requirements in actual working conditions. For example, when simulating three-phase electricity, it ensures that the phase difference of the three-phase voltage and current meets the standard.

[0069] The first voltage amplifier unit working process:

[0070] The first voltage amplifier unit receives the 3-way 0-5VAC analog sine wave small signal output by the control unit, amplifies it and outputs it as 3-way AC 150V.

[0071] The amplified AC 150V signal is sent to the current booster, which boosts the current to 100A. During the current boosting process, the current transformer recovers the output current in real time and transmits the recovery signal to the control unit.

[0072] The control unit compares the collected current signal with the preset current value, and adjusts the analog small signal output to the first voltage amplifier unit through a closed-loop regulation algorithm, thereby accurately controlling the size and stability of the output current to ensure that it remains within the required range during the entire test process. The maximum output current is 100A and the output time can reach 30S.

[0073] The working process of the second voltage amplifier unit:

[0074] The second voltage amplifier unit receives the other three 0-5VAC analog sine wave small signals output by the control unit, amplifies them and outputs them as three AC 150V.

[0075] These three AC 150V signals are boosted to AC400V by the booster, and voltage is recovered through the auxiliary tap 0-10VAC.

[0076] The recovered voltage signal is transmitted to the control unit, which compares it with the preset voltage value and performs closed-loop regulation to ensure the accuracy and stability of the output voltage so that it meets the test requirements.

[0077] Working mode of electric voltage regulator:

[0078] The electric voltage regulator receives a 0-5VDC drive signal output by the control unit and drives the high-power transformer output.

[0079] Its output voltage can be switched between UA, UB, and UC output voltages, and the switching operation is achieved through software settings. The user sets the output voltage switching mode and time interval and other parameters in the host computer software according to the test requirements. The control unit controls the electric voltage regulator to accurately switch the output voltage according to these settings to simulate different power supply conditions. The output is wired to the AC0-220V interface of the panel to provide variable AC voltage input for the Mabao drawer cabinet.

[0080] Zero-crossing detection circuit function realization:

[0081] The zero-crossing detection circuit performs zero-crossing detection on the input AC220V, and generates a reference voltage reference signal when it is detected that the voltage signal transitions from the positive half cycle to the negative half cycle or from the negative half cycle to the positive half cycle.

[0082] This signal is output to the FPGA in the control unit. The FPGA uses this signal as a time reference to accurately control the phase of the output voltage and current, so that the signal phase output by the tester is consistent with the phase relationship of the actual power grid power supply signal, thereby improving the authenticity and accuracy of the test.

[0083] Signal acquisition unit operation process:

[0084] The signal acquisition unit is responsible for collecting a variety of signals. For a 4-20mA DC small signal, it is sampled through a high-precision sampling circuit, and the analog signal is converted into a digital signal and transmitted to the control unit for processing and analysis.

[0085] Through the input and output board, 4-way input quantities are sampled, such as the switch status and fault alarm signal of the Mabao drawer cabinet, and 6-way output quantities are output according to the test requirements. For example, the start and stop operation signals of the Mabao drawer cabinet are controlled, so as to realize the signal interaction and control between the tester and the Mabao drawer cabinet.

[0086] Working principle of power conversion unit:

[0087] The power conversion unit receives AC220V input power and processes it through an isolation transformer and a rectifier and voltage stabilization circuit.

[0088] Isolated output 110V / 220VDC, users can switch between 110V and 220V through the toggle switch on the panel. According to the power requirements of different modules inside the tester, it provides a stable and isolated DC power supply to ensure the normal operation of each circuit of the tester and avoid power interference between different modules.

[0089] (III) Testing process of Mabao drawer cabinet

[0090] Test project execution:

[0091] like Figure 2 As shown, the tester simulates the instructions from the operating column and DCS, as well as the process conditions from the control system according to the test plan configured by the upper computer software, and conducts a comprehensive test on the Mabao drawer cabinet.

[0092] In various start-stop operation tests, the tester outputs corresponding voltage and current signals to simulate the starting and stopping process of the motor, and detects the performance of the Mabao drawer cabinet at the moment of starting and stopping and during stable operation, including whether the contactor's attraction and release actions are normal and whether the protection circuit responds in time.

[0093] During the interlocking parking test, the tester simulates the interlocking relationship between multiple devices. When a certain condition is triggered, the output signal causes the Mabao drawer cabinet to perform the interlocking parking action to check the reliability and accuracy of its interlocking function.

[0094] In the external fault parking function test, the tester simulates external fault conditions such as short circuit and overload, and outputs corresponding fault signals to the Mabao drawer cabinet to observe whether it can detect the fault in time and perform the parking operation to protect the safety of the motor and equipment.

[0095] During the power shake / power loss / power-on restart function test, the tester simulates instantaneous fluctuations in grid voltage (power shake), complete power loss, and power-on again to detect the Mabao drawer cabinet's ability to cope with these special conditions, such as whether it can keep the motor running after a power shake or correctly memorize the status after a power loss and restart safely when power is restored.

[0096] For DO and AO signal monitoring, the tester collects the DO (digital output) signals output by the Macbao drawer cabinet, such as alarm signals, status indication signals, etc., through the signal acquisition unit, and monitors its AO (analog output) signals, such as current and voltage feedback signals, to determine whether its output signals meet expectations.

[0097] In the overload protection, leakage protection, phase loss protection and thermal resistor protection tests, the tester simulates fault conditions such as overload, leakage, phase loss and thermal resistor abnormality, and outputs corresponding signals to the Mabao drawer cabinet to check whether its protection function can operate in a timely and accurate manner, and whether the protection threshold meets the set requirements.

[0098] Through the above detailed implementation methods, the motor protection cabinet automatic testing system of the present invention can efficiently and accurately perform comprehensive testing on the motor protection drawer cabinet, improve the testing efficiency and quality, and provide strong support for the performance evaluation and quality control of the motor protection cabinet.

[0099] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A motor protection cabinet automatic testing system, characterized in that: The test system includes: Portable PC, used to run the host computer software and configure the test plan; The tester communicates with the portable PC via a proprietary protocol, including: The power supply unit adopts AC220V power supply; The control unit, with DSP+FPGA as the core, controls the DA to output 7 analog small signals, of which 3 analog sine wave small signals 0-5VAC drive the first voltage amplifier unit to output 3 AC 150V, and another 3 analog sine wave small signals 0-5VAC drive the second voltage amplifier unit to output 3 AC 150V, and 1 0-5VDC drives the electric voltage regulator to output AC0-220V; The first voltage amplifier unit amplifies the driving signal and outputs three-way AC 150V, which is then boosted to 100A by a current booster, and the output current is recovered through a current transformer; The second voltage amplifier unit amplifies the driving signal and outputs 3-way AC 150V, which is then boosted to AC400V by a booster, and at the same time, voltage recovery is performed through an auxiliary tap 0-10VAC; Electric voltage regulator drives the high-power transformer output, whose output can be switched between UA, UB, and UC output voltages and the output wiring is connected to the panel output AC0-220V; The zero-crossing detection circuit performs zero-crossing detection on the input AC220V and outputs a reference voltage reference signal to the FPGA in the control unit; The signal acquisition unit is used to sample 1 channel of 4-20mA DC small signal, sample 4 channels of binary input quantities through the binary input and output board, and output 6 channels of binary output quantities; Power conversion unit, isolated output 110V / 220VDC, switched by the toggle switch on the panel; Mabao drawer cabinet, connected to the tester, receives the voltage and current output by the tester for testing; Control cables and signal cables are used to connect the tester and the Mabao drawer cabinet; Type-C dedicated cable, used to connect a portable PC to the tester.

2. The motor protection cabinet automatic testing system according to claim 1, characterized in that: The three-way AC 150V output by the first voltage amplifier unit is boosted to 100A by the current booster, and then the output current is recovered through the current transformer, and the recovered current signal is transmitted to the control unit for closed-loop regulation.

3. The motor protection cabinet automatic testing system according to claim 1, characterized in that: The three-way AC 150V output by the second voltage amplifier unit is boosted to AC400V by the booster, and then voltage is recovered through the auxiliary tap 0-10VAC. The recovered voltage signal is transmitted to the control unit for closed-loop regulation.

4. The motor protection cabinet automatic testing system according to claim 1, characterized in that: The electric voltage regulator drives the high-power transformer output to switch between the output voltages UA, UB, and UC through software settings.

5. The motor protection cabinet automatic testing system according to claim 1, characterized in that: The host computer software has the functions of scheme configuration, network configuration, device connection, scheme import, test start, report save, test stop, device reset, AC test, status sequence, and open / save report. The scheme configuration is assisted by on-site testing professional technicians to complete the test scheme settings for different devices and different current loops.

6. The motor protection cabinet automatic testing system according to claim 1, characterized in that: The FPGA in the control unit controls the phase of the output voltage and current according to the reference voltage reference signal output by the zero-crossing detection circuit.

7. The motor protection cabinet automatic test system according to claim 1, characterized in that: The signal acquisition unit samples 4-way binary input quantities and outputs 6-way binary output quantities through a binary input and output board, and simultaneously samples 1-way 4-20mA DC small signal.

8. The motor protection cabinet automatic testing system according to claim 1, characterized in that: The power conversion unit outputs 110V / 220VDC in isolation, and switches between 110V and 220V via a toggle switch on the panel.

9. The motor protection cabinet automatic testing system according to claim 1, characterized in that: The tester simulates the instructions from the operating column and DCS and the process conditions from the control system according to the test plan configured by the upper computer software, and performs various start-stop operation tests, interlocking action parking tests, external fault parking function tests, power shake / power loss / power-on restart function tests, DO and AO signal monitoring, and overload protection, leakage protection, phase loss protection, and thermal resistance protection tests on the Mabao drawer cabinet.

10. The motor protection cabinet automatic testing system according to claim 1, characterized in that: The control unit of the tester controls the DA to output 7 analog small signals, of which 3 are used to drive the first voltage power amplifier unit to output and increase the current, 3 are used to drive the second voltage power amplifier unit to output and increase the voltage, and 1 is used to drive the electric voltage regulator output. The voltage and current amplitude and phase of each output can be adjusted independently. The maximum output of the 3 large currents output by the first voltage power amplifier unit is 100A, and the output time is 30S.

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