A power distribution automation terminal insulation performance integrated verification system and method

Abstract

This invention discloses an integrated insulation performance verification system and method for distribution automation terminals. The system consists of a host computer, an automated insulation performance verification unit, a terminal interface adapter module, insulation resistance measuring equipment, dielectric strength measuring equipment, and impulse voltage measuring equipment. The automated insulation performance verification unit has a built-in high-voltage electrode matrix switching circuit, which enables automatic selection between the test equipment and the electrical interfaces of the terminal under test. Combined with the host computer's automated verification software, it completes integrated automatic verification of insulation resistance, dielectric strength, and lightning impulse voltage insulation performance. The method achieves full-item testing with a single wiring operation through system initialization self-test, one-time full interface access of the terminal, automatic channel selection verification, fully automatic test execution, anomaly safety protection, and automatic report generation. This invention eliminates manual wiring errors and high-voltage operation risks, is compatible with multiple terminal models, and automates the testing process, significantly improving the efficiency and safety of insulation testing for distribution automation terminals.

Description

Technical Field

[0001] This invention relates to the field of power system distribution network automation equipment testing technology, and in particular to an integrated verification system and method for the insulation performance of distribution automation terminals. Background Technology

[0002] As the core underlying equipment of the distribution network automation system, distribution automation terminals are widely used in scenarios such as distribution network fault detection, load monitoring, and remote control. Their insulation performance is a core indicator for ensuring the safe and stable operation of the distribution network and preventing electrical accidents. Insulation resistance, dielectric strength, and lightning impulse voltage are three mandatory industry inspection items for distribution automation terminals, including factory inspection, grid connection qualification testing, on-site operation and maintenance, and periodic performance verification. These directly determine whether the terminal can be safely connected to the grid and operate reliably in the long term.

[0003] Current distribution automation terminal insulation testing still relies on the traditional, discrete, manual testing method. The three tests require separate wiring modifications and instrument replacements, necessitating multiple manual operations for each terminal, which cannot meet the testing needs of mass production and maintenance. Manual high-voltage wiring poses a risk of electric shock and is prone to human error such as wiring mistakes, insufficient pressurization time, and parameter setting deviations, resulting in inconsistent test results and a high misjudgment rate, failing to meet the standardized management requirements of the power industry. Different manufacturers and models of distribution automation terminals have significantly different interface definitions and terminal layouts; existing testing equipment lacks a universal adaptation design, requiring multiple sets of customized wiring fixtures, resulting in insufficient versatility and scalability. Existing equipment cannot achieve coordinated control and automatic switching of multiple testing instruments, cannot complete all tests with a single wiring connection, and data acquisition and report generation require manual processing, leading to poor traceability of test data. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide an integrated verification system and method for the insulation performance of power distribution automation terminals.

[0005] To achieve the objectives of this invention, the technical solution adopted is as follows: An integrated insulation performance verification system for power distribution automation terminals includes a host computer, an automated insulation performance verification unit, a terminal interface adapter module, an insulation resistance measuring device, a dielectric strength measuring device, and an impulse voltage measuring device. The automated insulation performance verification unit is connected to the host computer, insulation resistance measuring device, dielectric strength measuring device, and impulse voltage measuring device respectively. The automated insulation performance verification unit is connected to all electrical interfaces of the power distribution automation terminal under test through the terminal interface adapter module. The automated insulation performance verification unit includes a high-voltage resistant insulation main frame, a high-voltage electrode matrix switching circuit, and a safety protection module, which is used to realize single-channel unique selection between the measuring equipment and each electrical interface of the power distribution automation terminal under test. The high-voltage electrode matrix switching circuit has a matrix topology structure with three independent high-voltage buses, corresponding to three types of testing equipment: insulation resistance, dielectric strength, and impulse voltage. It features multiple independent test channels, each corresponding to an electrical interface of the power distribution automation terminal under test, with a one-to-one correspondence between the channel and the port of the terminal interface adapter module. A matrix contact switch array is used, employing a combination of high-voltage vacuum contactors and high-voltage sealed relays to form the matrix switch array. Each switch independently controls the connection and disconnection of its corresponding channel and bus. The host computer has built-in automated verification software to achieve integrated automatic verification of the insulation performance of the power distribution automation terminal, including insulation resistance, dielectric strength, and lightning impulse voltage.

[0006] Furthermore, a dual electrical and software interlocking structure is set between the switching channel and the high-voltage busbar. Residual voltage detection is performed before channel switching, and switching is only allowed after confirming that the residual voltage is below the safety threshold.

[0007] Furthermore, electrical interlocks forcefully prevent multiple high-voltage contacts from closing simultaneously through physical circuits; software interlocks are controlled by software state machines, which perform secondary confirmation of the selection command, allowing only one measuring device to be connected to one measured channel at a time.

[0008] Furthermore, the high-voltage electrode matrix switching circuit drive design is divided into a low-voltage drive circuit and a high-voltage execution circuit. The low-voltage drive circuit includes an FPGA controller, an optocoupler isolation module, and a 24V drive circuit, while the high-voltage execution circuit includes a high-voltage vacuum contactor, a high-voltage sealed relay, and a high-voltage contact output terminal. The FPGA controller issues a strobe command, and the 24V drive circuit outputs a stable drive current to power the pull-in coil. The pull-in coil's action triggers the contact action of the high-voltage execution circuit, completing the on / off switching of the high-voltage channel.

[0009] Furthermore, the safety protection module incorporates an overcurrent protection unit, a high-voltage discharge unit, and a grounding discharge unit.

[0010] Furthermore, the overcurrent protection unit has a built-in high-precision leakage current acquisition circuit, which immediately cuts off the high-voltage output and locks out when the leakage current exceeds the action threshold; the high-voltage discharge unit has a high-power discharge resistor connected in parallel to each switching channel, and the discharge is automatically triggered during test intervals and after the test; the grounding discharge unit is equipped with a forced grounding circuit, and all channels are automatically grounded when the system is powered off, triggered by emergency stop, or when the test ends, to eliminate the risk of residual voltage.

[0011] Furthermore, the terminal interface adaptation module includes a universal adaptation base and a replaceable interface module; The universal adapter base has a built-in backplane bus, and the backplane bus channels correspond one-to-one with the test channels of the automatic insulation performance verification unit, using spring-press type quick-connect terminal blocks. The replaceable interface module adopts a snap-on installation structure and has a unique coded identifier.

[0012] Furthermore, the automated verification software includes a master control scheduling module, a device communication module, a channel switching control module, a data acquisition and processing module, a safety interlock module, and a report generation module; The main control scheduling module is responsible for the overall scheduling and anomaly handling of the test process; the equipment communication module realizes full-duplex communication with the verification unit and the three types of test equipment; the channel switching control module issues channel switching commands, verifies the interlock status, and allows high voltage output only after confirming that the channel is conducting normally; the data acquisition and processing module acquires test voltage, current, resistance, and status data in real time, and completes filtering, storage, and automatic qualification judgment; the safety interlock module monitors emergency stop, overcurrent, and breakdown safety signals in real time, and immediately triggers emergency shutdown and high voltage discharge in case of abnormality; the report generation module automatically generates test reports that comply with power industry standards.

[0013] An integrated verification method for the insulation performance of power distribution automation terminals includes the following steps: S1, after the system is powered on, it completes the initialization self-test and verifies the status of communication, safety interlocks and high-voltage circuits; S2, the terminal under test connects to all interfaces at once through the terminal interface adapter module and selects the test items and parameters; S3, the system controls the automatic insulation performance verification unit to complete the automatic selection of test channels and corresponding test equipment, perform residual voltage detection before channel switching, and verify the interlock status and channel continuity after confirming that the residual voltage is lower than the safety threshold. S4, the system controls the corresponding test equipment to perform automated tests, including insulation resistance test, dielectric strength test, and impulse voltage test, and collects data in real time and completes the pass / fail determination; matrix operation is prohibited during high voltage output; S5. After the single-port test is completed, a forced discharge is performed. After the residual voltage meets the standard, the system automatically switches to the next port and repeats S3-S4. After all tests are completed, the entire channel is grounded and discharged and the high-voltage blockade is released. S6, if an abnormality occurs during testing, immediately cut off all high-voltage outputs, ground discharge all channels and lock the switching action, and record the abnormal data; S7 automatically summarizes the data and generates and exports the test report after the entire process is completed.

[0014] The beneficial effects of this invention are as follows: Compared with the prior art, this invention solves the problem of multiple disassembly and rewiring required for multi-item testing, enabling the tested terminal to complete all three insulation performance tests automatically with a single wiring connection; through the high-voltage matrix automatic switching unit, it achieves parallel access and interlocked automatic selection of three types of testing equipment—insulation resistance, dielectric strength, and impulse voltage—eliminating the safety risks and human errors of manual operation; through a universal terminal interface adaptation design, it is compatible with all interfaces of distribution automation terminals from different manufacturers and of different models, achieving tool-free rapid adaptation; and it achieves full automation of the testing process, automatic data acquisition, automatic qualification judgment, and automatic generation of test reports. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of an integrated insulation performance verification system for power distribution automation terminals as described in this invention; Figure 2 This is a schematic diagram of a high-voltage electrode matrix switching circuit; Figure 3 This is a schematic diagram of the high-voltage electrode matrix switching circuit drive design; Figure 4 This is a schematic diagram of the terminal interface adapter module; Figure 5 This is a schematic diagram of an integrated verification method for the insulation performance of power distribution automation terminals as described in this invention. Detailed Implementation

[0016] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of this application.

[0017] like Figure 1 As shown, the present invention discloses an integrated insulation performance verification system for distribution automation terminals, which performs integrated automatic verification of three insulation performance parameters of distribution automation terminals (DTU / FTU / TTU): insulation resistance, dielectric strength, and lightning impulse voltage. The system includes a host computer, an automated insulation performance verification unit, a terminal interface adapter module, insulation resistance measuring equipment, dielectric strength measuring equipment, and impulse voltage measuring equipment.

[0018] The automated insulation performance verification unit communicates and is electrically connected to the host computer, insulation resistance measuring equipment, dielectric strength measuring equipment, and impulse voltage measuring equipment. Simultaneously, the automated insulation performance verification unit is electrically connected to all electrical interfaces of the power distribution automation terminal under test via a terminal interface adapter module. The host computer communicates with and controls the insulation resistance measuring equipment, dielectric strength measuring equipment, and impulse voltage measuring equipment.

[0019] The automated insulation performance verification unit incorporates a high-voltage electrode matrix switching circuit to enable single-channel unique selection between each interface of the three types of measuring equipment and the terminal under test. The host computer contains automated verification software to send control commands to the automated insulation performance verification unit and the three types of measuring equipment, collect test data, automatically complete the insulation performance testing process, and generate a test report.

[0020] The automated insulation performance verification unit includes a high-voltage resistant insulation main frame, a high-voltage electrode matrix switching circuit, and a safety protection module. The main frame is integrally molded from SMC high-voltage resistant insulation material, with a volume resistivity ≥1×10^14Ω・cm, meeting the insulation requirements for high-voltage testing of 12kV and below. Insulating partitions are installed between each test channel, and the creepage distance between adjacent channels is set according to the withstand voltage level, completely eliminating the risks of high-voltage arcing, crosstalk, and short circuits.

[0021] like Figure 2 As shown, the high-voltage electrode matrix switching circuit has a matrix topology and is the core unit for realizing automatic multi-channel selection and safety interlocking of three types of test equipment and the terminal under test.

[0022] The high-voltage electrode matrix switching circuit is equipped with three independent high-voltage buses and a reserved extension high-voltage bus. The buses are electrically isolated from each other and correspond to three types of test equipment: insulation resistance, dielectric strength, and impulse voltage, as well as reserved extension equipment, to realize independent access to different test high-voltage sources.

[0023] Multiple independent test channels (CH1~CHN) are provided, each corresponding to an electrical interface of the power distribution automation terminal under test. Each channel corresponds one-to-one with the port of the terminal interface adapter module, enabling independent testing of all terminal interfaces.

[0024] The matrix contact switch uses a combination of high-voltage vacuum contactors and high-voltage sealed relays to form an N×M matrix switch array (S11~SNM). Each row corresponds to N channels under test (CH1~CHN), and each column corresponds to M high-voltage buses. Each switch (SXY) independently controls the connection / disconnection of the Xth channel and the Yth bus, achieving precise selection between a single channel and a single test device. The electrode unit is made of T2 silver-plated copper, with a contact resistance ≤5mΩ, arc resistance, and corrosion resistance, ensuring the stability of the high-voltage circuit conduction.

[0025] The high-voltage electrode matrix switching circuit assigns an independent switching channel to each tested terminal interface, and a separate high-voltage busbar to each type of test equipment. A matrix-type contact switch connects the busbar and the channel, and independent switching contacts are provided between the switching channel and the high-voltage busbar.

[0026] Before switching channels, residual voltage is checked, and switching is only permitted after confirming that the residual voltage is below the safety threshold. A dual electrical and software interlock structure is implemented between the switching channel and the high-voltage busbar, allowing only one measuring device to be connected to one channel at a time, eliminating the safety risk of multiple high-voltage sources outputting in parallel. The electrical interlock uses physical circuitry to forcibly prevent multiple high-voltage contacts from engaging simultaneously, eliminating accidental connection between the channel and the busbar at the hardware level. The software interlock is controlled by a software state machine, which performs secondary confirmation of the selection command, verifying the connection conditions between the channel and the busbar, forming a software-layer safety protection.

[0027] The double interlocking workflow starts in the initial state, where all channels and buses are not selected and there is no high-voltage output. Once the target channel under test and the corresponding high-voltage bus under test are selected, the safety conditions are first verified by the hardware interlocking circuit, and then the permission signal is confirmed a second time by the software state machine. Only when the double verification is passed will the connection action of a single channel and bus be executed, while the other contacts remain open.

[0028] like Figure 3 As shown, the high-voltage electrode matrix switching circuit drive design is divided into two parts: a low-voltage drive circuit and a high-voltage execution circuit. The low-voltage drive circuit is responsible for issuing commands and verifying status, while the high-voltage execution circuit is responsible for switching the high-voltage channel on and off. Electrical separation is achieved through the coil.

[0029] The low-voltage drive circuit includes an FPGA controller, an optocoupler isolation module, and a 24V drive circuit. The FPGA controller issues gating commands, receives interlock signals, and controls the contact engagement / disengagement. The 24V drive circuit outputs a stable 24V drive current to power the engagement coil, triggering the contact action of the high-voltage execution circuit. The high-voltage execution circuit includes a high-voltage vacuum contactor, a high-voltage sealed relay, and high-voltage contact output terminals. Relying on the engagement coil action, it completes the switching of the high-voltage channel. The high-voltage contact output terminals are connected to the high-voltage busbar of the high-voltage electrode matrix switching circuit and the channel under test. Low-voltage control and high-voltage execution eliminate the risk of electric shock to operators. Complete isolation between high and low voltages protects the controller and low-voltage circuits from high-voltage damage, meeting the insulation and safety specifications for 12kV and below high-voltage testing.

[0030] The safety protection module incorporates an overcurrent protection unit, a high-voltage discharge unit, and a grounding discharge unit. The overcurrent protection unit features a high-precision leakage current acquisition circuit with a measurement range of 0-100mA and a measurement accuracy of 0.1mA. The preferred leakage current action threshold is set at 0.25mA (based on 5% of the measured product's leakage current specification). Exceeding this threshold immediately cuts off the high-voltage output and locks the circuit. The high-voltage discharge unit has a high-power discharge resistor connected in parallel to each switching channel. Discharge is automatically triggered during test intervals and after the test, reducing the residual voltage in the circuit to below the safe voltage of 36V within 3 seconds. The grounding discharge unit features a forced grounding circuit. Upon system power failure, emergency stop triggering, or the end of the test, all channels are automatically grounded, completely eliminating the risk of residual voltage.

[0031] like Figure 4 As shown, the terminal interface adapter module includes a universal adapter base and a replaceable interface module. The universal adapter base has a built-in backplane bus that corresponds one-to-one with the channels of the automated insulation performance verification unit. The backplane bus channels correspond one-to-one with the test channels of the automated insulation performance verification unit, ensuring stable transmission of test signals. The access method adopts a spring-loaded quick-connect terminal block, which is compatible with M3-M5 screw terminals and pluggable terminals for tool-free quick access, eliminating the need for manual screwing and wiring.

[0032] The replaceable interface modules adopt a unified snap-on installation structure, interfacing with the backplane bus of the universal base, allowing for tool-free and wiring-free replacement. Each module has a unique identification code, enabling the system to automatically identify the module type and port definition, and automatically match the test configuration without manual setup. Standardized replaceable interface modules are designed for various manufacturers' DTU / FTU interfaces, including aviation connectors, Ethernet interfaces, RS485 interfaces, and dedicated custom interfaces.

[0033] The base also incorporates a high-voltage isolation circuit, completely isolating the low-voltage communication port from the high-voltage test circuit to prevent damage to the terminal's low-voltage circuit from the high voltage test. The base is also designed with a foolproof structure; all interfaces and modules are equipped with foolproof features to prevent wiring errors caused by mis-insertion or reverse insertion. Additionally, it has a built-in port status detection circuit that automatically identifies the number, type, and on / off status of connected ports, supporting automatic skipping of default ports and customizable port test sequence configuration.

[0034] This insulation resistance measuring device outputs an adjustable DC test voltage of 500V / 1000V / 2500V to perform insulation resistance tests on each port of the tested terminal. The insulation resistance measurement range is 0-10GΩ, with a measurement accuracy of ±5% and voltage stability ≤±1%. The device receives commands from a host computer to complete voltage output, measurement, stop, and discharge actions. After the test, it immediately transmits data such as insulation resistance value, leakage current value, and test duration. The device has built-in short-circuit and overcurrent protection; in the event of a short circuit, it immediately cuts off the voltage and triggers an alarm.

[0035] This dielectric strength measuring device outputs a continuously adjustable 0-5kV power frequency sinusoidal voltage (50Hz) to complete the power frequency withstand voltage test of the tested terminal. The voltage adjustment accuracy is 0.1kV, the leakage current measurement range is 0-100mA with an accuracy of 0.1mA, and the holding time is customizable with a timing error ≤±1s. The device is linked with an automated insulation performance verification unit. After channel switching is completed and no abnormalities are confirmed, it automatically executes the entire process of voltage boosting, holding, voltage reduction, and discharging. In case of breakdown or overcurrent, protection is immediately triggered and abnormal data is transmitted back. The device has built-in breakdown protection, overcurrent protection, and flashover detection. In case of breakdown, the high-voltage output is cut off within ≤10ms, and all switching actions are locked simultaneously.

[0036] The impulse voltage measurement device outputs a standard lightning impulse voltage waveform (1.2 / 50μs) to complete the lightning impulse withstand voltage test of the tested terminal. The impulse voltage amplitude is adjustable from 0-12kV, and the positive and negative polarity of the impulse, the number of impulses, and the impulse interval can be set. The impulse voltage measurement device is linked with the calibration unit; after channel interlock confirmation, it automatically completes the charging, impulse triggering, insulation detection, and discharge process, and automatically records flashover and breakdown events and their corresponding times. The impulse voltage measurement device has built-in overvoltage protection and misoperation interlock, and automatically grounds and discharges when not in test mode to eliminate the risk of residual voltage.

[0037] The automated verification software includes a main control scheduling module, an equipment communication module, a channel switching control module, a data acquisition and processing module, a safety interlock module, and a report generation module. It can automatically complete the entire process of testing insulation resistance, dielectric strength, and impulse voltage after a single wiring.

[0038] The main control scheduling module is responsible for the overall scheduling and anomaly handling of the test process; the equipment communication module realizes full-duplex communication with the verification unit and three types of test equipment, and supports the Modbus-RTU / TCP standard protocol; the channel switching control module issues channel switching commands, verifies the interlock status, and allows high voltage output only after confirming that the channel is conducting normally; the data acquisition and processing module acquires test voltage, current, resistance, and status data in real time, and completes filtering, storage, and automatic qualification judgment; the safety interlock module monitors safety signals such as emergency stop, overcurrent, and breakdown in real time, and immediately triggers emergency shutdown and high voltage discharge in case of abnormality; the report generation module automatically generates test reports that comply with power industry standards and supports export in PDF / Excel format.

[0039] like Figure 5 As shown, the integrated verification method for insulation performance of power distribution automation terminals according to the present invention includes the following steps: S1, System initialization self-test, confirms that communication, safety interlocks, and high-voltage circuit status are normal; After the system is powered on, it completes hardware self-test, communication link verification, high-voltage circuit discharge reset, and emergency stop circuit and safety interlock status detection. If the self-test fails, the system will prevent the system from entering the test process, display a fault message, and lock the operation.

[0040] S2, the terminal under test completes one-time full interface access through the terminal interface adapter module, the system identifies the terminal configuration, and selects test items and parameters; The system automatically identifies the terminal model and port configuration. Users can select single-item insulation resistance test, single-item dielectric strength test, single-item impulse voltage test, or three-item full automatic test and set the corresponding test parameters.

[0041] S3, the system controls the automatic insulation performance verification unit to complete the automatic selection of test channels and corresponding test equipment, performs residual voltage detection before channel switching, and verifies the interlock status after confirming that the residual voltage is lower than the safety threshold. The system controls the automated insulation performance verification unit to select the corresponding test channels and test equipment according to the preset test sequence, verify the interlock status and channel continuity, and enter the test phase after confirming that there are no errors.

[0042] S4, the system controls the corresponding test equipment to perform automated testing, collects test data in real time, and completes the pass / fail determination; matrix operation is prohibited during high voltage output; Insulation resistance test: The host computer issues a command, and the insulation resistance measuring device outputs an adjustable DC test voltage of 500V / 1000V / 2500V, which is stably output to the selected channel. Once the voltage reaches the set value, it remains stable until it stabilizes, ensuring accurate measurement. The insulation resistance value (0~10GΩ) is acquired in real time, and the test duration is recorded. When the test time is up, the device automatically stops the high-voltage output, performs high-voltage discharge and grounding, releasing residual voltage. The resistance value is compared to the standard, automatically determining whether it is qualified or unqualified, and the results are stored.

[0043] Dielectric strength test: The dielectric strength measuring equipment outputs a continuously adjustable 50Hz power frequency sinusoidal voltage of 0~5kV, which is uniformly increased to the set value; the set voltage is maintained for 1 minute by default, with a timing error ≤±1s; leakage current (0~100mA, accuracy 0.1mA) is monitored throughout the process to detect breakdown and flashover phenomena; after the voltage holding period ends, the voltage is uniformly reduced to zero; high-voltage output is stopped, and high-voltage discharge and grounding discharge are performed to release residual voltage. If there is no breakdown, flashover, and leakage current does not exceed the standard during the voltage holding period, the test is considered qualified.

[0044] Impulse voltage test: The impulse voltage measuring device charges the energy storage circuit and outputs an adjustable standard 1.2 / 50 μs lightning impulse waveform from 0 to 12 kV; it automatically triggers impulses according to the set parameters (positive / negative polarity, number of impulses, interval time); it monitors and records flashover and breakdown events and their occurrence times in real time; after completing the set number of impulses, it stops charging and triggering, performs high-voltage discharge and grounding discharge to release the residual voltage. If there is no breakdown and no destructive flashover, it is judged as qualified.

[0045] S5, after the single-port test is completed, perform forced discharge. After the residual voltage meets the standard, automatically switch to the next port, and repeat steps S3 - S4 until all test items are completed. Then the system triggers full-channel grounding discharge to解除高压闭锁; S6, when abnormalities such as overcurrent, breakdown, flashover, and emergency stop trigger occur during the test, the system immediately cuts off all high-voltage outputs, triggers full-channel grounding discharge, locks all switching actions, pops up an abnormality prompt, and records the abnormal data. S7, after the entire process is completed, the system automatically summarizes the test data, generates, and exports the test report.

[0046] The system automatically summarizes all test data, generates a test report according to a preset template, including terminal information, test parameters, test data, qualified / unqualified judgment, test time, operator, etc. information, and supports export and printing.

[0047] The applicant of the present invention has made a detailed description and explanation of the embodiments of the present invention in combination with the accompanying drawings of the specification. However, those skilled in the art should understand that the above embodiments are only the preferred implementation schemes of the present invention. The detailed description is only to help readers better understand the spirit of the present invention, rather than a limitation on the protection scope of the present invention. On the contrary, any improvement or modification based on the spirit of the present invention should fall within the protection scope of the present invention.

Claims

1. A power distribution automation terminal insulation performance integrated verification system, characterized in that, It includes a host computer, an automated insulation performance verification unit, a terminal interface adapter module, insulation resistance measuring equipment, dielectric strength measuring equipment, and impulse voltage measuring equipment; The automated insulation performance verification unit is connected to the host computer, insulation resistance measuring device, dielectric strength measuring device, and impulse voltage measuring device respectively. The automated insulation performance verification unit is connected to all electrical interfaces of the power distribution automation terminal under test through the terminal interface adapter module. The automated insulation performance verification unit includes a high-voltage resistant insulation main frame, a high-voltage electrode matrix switching circuit, and a safety protection module, which is used to realize single-channel unique selection between the measuring equipment and each electrical interface of the power distribution automation terminal under test. The high-voltage electrode matrix switching circuit has a matrix topology structure with three independent high-voltage buses, which correspond to three types of test equipment: insulation resistance, dielectric strength, and impulse voltage. Multiple independent test channels are set up, each channel corresponds to an electrical interface of the power distribution automation terminal under test, and corresponds one-to-one with the port of the terminal interface adapter module; a matrix contact switch is set up, using a combination of high-voltage vacuum contactors and high-voltage sealed relays to form a matrix switch array, and each switch independently controls the on / off of the corresponding channel and the bus. The host computer has built-in automated verification software to achieve integrated automatic verification of the insulation performance of the power distribution automation terminal, including insulation resistance, dielectric strength, and lightning impulse voltage.

2. The integrated insulation performance verification system for distribution automation terminals according to claim 1, characterized in that, A dual electrical and software interlocking structure is set between the switching channel and the high-voltage bus. Residual voltage detection is performed before channel switching, and switching is only allowed after confirming that the residual voltage is below the safety threshold.

3. The integrated insulation performance verification system for distribution automation terminals according to claim 2, characterized in that, Electrical interlocks forcefully prevent multiple high-voltage contacts from closing simultaneously through physical circuits; software interlocks are controlled by a software state machine, which performs secondary confirmation of the selection command, allowing only one measuring device to be connected to one measured channel at a time.

4. The integrated insulation performance verification system for distribution automation terminals according to claim 1, characterized in that, The high-voltage electrode matrix switching circuit drive design is divided into a low-voltage drive circuit and a high-voltage execution circuit. The low-voltage drive circuit includes an FPGA controller, an optocoupler isolation module, and a 24V drive circuit. The high-voltage execution circuit includes a high-voltage vacuum contactor, a high-voltage sealed relay, and a high-voltage contact output terminal. The FPGA controller issues a strobe command, and the 24V drive circuit outputs a stable drive current to power the pull-in coil. The pull-in coil's action triggers the contact action of the high-voltage execution circuit, completing the on / off switching of the high-voltage channel.

5. The integrated insulation performance verification system for distribution automation terminals according to claim 1, characterized in that, The safety protection module has a built-in overcurrent protection unit, a high-voltage discharge unit, and a grounding discharge unit.

6. The integrated insulation performance verification system for distribution automation terminals according to claim 5, characterized in that, The overcurrent protection unit has a built-in high-precision leakage current acquisition circuit. If the leakage current exceeds the action threshold, it will immediately cut off the high voltage output and lock out. The high voltage discharge unit has a high-power discharge resistor connected in parallel for each switching channel. The discharge is automatically triggered during test intervals and after the test. The grounding discharge unit is equipped with a forced grounding circuit. All channels are automatically grounded when the system is powered off, triggered by an emergency stop, or when the test ends, eliminating the risk of residual voltage.

7. The integrated insulation performance verification system for distribution automation terminals according to claim 1, characterized in that, The terminal interface adaptation module includes a universal adaptation base and a replaceable interface module. The universal adapter base has a built-in backplane bus, and the backplane bus channels correspond one-to-one with the test channels of the automatic insulation performance verification unit, using spring-press type quick-connect terminal blocks. The replaceable interface module adopts a snap-on installation structure and has a unique coded identifier.

8. The integrated insulation performance verification system for distribution automation terminals according to claim 1, characterized in that, The automated verification software includes a main control scheduling module, a device communication module, a channel switching control module, a data acquisition and processing module, a safety interlock module, and a report generation module; The main control scheduling module is responsible for the overall scheduling and anomaly handling of the test process; the equipment communication module realizes full-duplex communication with the verification unit and the three types of test equipment; the channel switching control module issues channel switching commands, verifies the interlock status, and allows high voltage output only after confirming that the channel is conducting normally; the data acquisition and processing module acquires test voltage, current, resistance, and status data in real time, and completes filtering, storage, and automatic qualification judgment; the safety interlock module monitors emergency stop, overcurrent, and breakdown safety signals in real time, and immediately triggers emergency shutdown and high voltage discharge in case of abnormality; the report generation module automatically generates test reports that comply with power industry standards.

9. A method for integrated verification of insulation performance of distribution automation terminals, based on the integrated verification system for insulation performance of distribution automation terminals as described in any one of claims 1-8, characterized in that, Includes the following steps: S1, after the system is powered on, it completes the initialization self-test and verifies the status of communication, safety interlocks and high-voltage circuits; S2, the terminal under test connects to all interfaces at once through the terminal interface adapter module and selects the test items and parameters; S3, the system controls the automatic insulation performance verification unit to complete the automatic selection of test channels and corresponding test equipment, perform residual voltage detection before channel switching, and verify the interlock status and channel continuity after confirming that the residual voltage is lower than the safety threshold. S4, the system controls the corresponding test equipment to perform automated tests, including insulation resistance test, dielectric strength test, and impulse voltage test, and collects data in real time and completes the pass / fail determination; matrix operation is prohibited during high voltage output; S5. After the single-port test is completed, a forced discharge is performed. After the residual voltage meets the standard, the system automatically switches to the next port and repeats S3-S4. After all tests are completed, the entire channel is grounded and discharged and the high-voltage blockade is released. S6, if an abnormality occurs during testing, immediately cut off all high-voltage outputs, ground discharge all channels and lock the switching action, and record the abnormal data; S7 automatically summarizes the data and generates and exports the test report after the entire process is completed.

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