Switch cabinet main loop resistor segment test and temperature rise test device and test method

Abstract

The invention discloses a switch cabinet main loop resistance segmented test and temperature rise test device and test method. The switch cabinet main loop resistance segmented test and temperature rise test device comprises a large current generator, a three-phase isolating switch, a switch cabinet main loop, a resistance automatic inspection module, a temperature rise acquisition instrument, a host console and a loop resistance instrument. The input / output end of the three-phase isolating switch is connected with the output end of the large current generator / the main loop wire inlet end of the switch cabinet; leading-out terminals of main loops of the switch cabinets are short-circuited; the temperature / resistance measuring end of the automatic resistance inspection module is connected with a switch cabinet main loop; the temperature output end is connected with a temperature rise acquisition instrument; a segmented resistance test first / second end connection loop resistance meter measures a voltage positive / negative electrode; the anode / cathode of the current source of the loop resistance meter is connected with the switch cabinet main loop resistance test input / output end; the host console starts a signal to a loop resistance meter power generation current source when the switch cabinet main loop / segment resistance is measured; and a temperature measurement / resistance temperature measurement circuit connection signal is sent to the automatic resistance inspection module during temperature rise test / segment resistance measurement. The method has the advantage of high test efficiency.

Description

Technical Field

[0001] This invention belongs to the field of switchgear technology, specifically relating to a switchgear main circuit resistance segmentation test and temperature rise test device and test method. Background Technology

[0002] Currently, when conducting temperature rise tests on high-voltage switchgear, a loop resistance meter is first used to test the resistance, then a pre-embedded thermocouple is used for the temperature rise test, and the loop resistance is tested again after the thermocouple used for the temperature rise test is removed.

[0003] If the main circuit resistance changes after the switchgear undergoes a temperature rise test, it is necessary to locate the position of the resistance change, open the switch and remove it from the switchgear, and then test the circuit resistance again. This will result in inaccurate measured resistance values ​​due to the switch action disrupting the original state, causing the defect that the position of the resistance change cannot be determined.

[0004] If the resistance measurement after the switch cabinet undergoes a temperature rise test needs to be performed in sections, the switch cannot operate and the space is limited, and the existing temperature rise test equipment cannot meet the requirements.

[0005] CN117929986A discloses a method for testing the temperature rise of switchgear in a substation, comprising the following steps: S1, assembling and connecting the switchgear according to the location of the switchgear on site, and short-circuiting a varying number of outgoing switchgear as needed, and detecting the temperature rise using no fewer than three wireless passive temperature sensors; S2, when current is input through the incoming port of the main incoming switchgear in the high-voltage room, the current of the temperature rise test device enters the incoming port of the main incoming switchgear through the long busbar, and is sequentially distributed through the outgoing switchgear, wherein the current flowing through the main transformer incoming switchgear during the test is... The requirements are: S3, when the main line cabinet is connected to the high-voltage outdoor busbar bridge to input current, the current of the temperature rise test device enters the busbar bridge through the long copper busbar, and then the current is added from the incoming line of the main incoming line cabinet. The current of the outgoing line cabinet is distributed in sequence, of which the current of the main incoming interval is the rated current of the circuit breaker, and the current of the other intervals is not less than 80% of the rated current of the circuit breaker. S4, the temperature rise of the tested equipment is detected by a wireless passive temperature sensor and transmitted to the temperature rise test device. However, this patent uses a passive temperature sensor to measure temperature, which is different from the temperature measurement principle and resistance test principle of this application.

[0006] CN115859734A This invention provides a method for real-time calculation of contact resistance and load capacity of switchgear during energized operation, including: establishing a 3D model of the switchgear and analyzing heat sources and temperature distribution; based on the results of the heat source and temperature distribution analysis, constructing a qualitative thermal circuit model for solving the steady-state temperature of the switchgear contacts; deriving qualitative expressions with undetermined coefficients for the switchgear contact temperature rise, contact resistance, and load current based on the qualitative thermal circuit model; transforming the qualitative expressions to obtain functional expressions relating the contact resistance of the switchgear contacts, the actual load capacity of the switchgear, and the currently measured steady-state temperature rise and load current; establishing a temperature fluid field model of the switchgear and quantitatively calculating the contact temperature rise; using the calculation results of the temperature fluid field, determining the undetermined coefficients to obtain the corresponding quantitative expressions. However, this patent mainly addresses the issue that the contact resistance of the isolating switch in the switchgear cannot be measured under energized conditions, which is different from the temperature measurement and resistance testing structure and principle of this application. Summary of the Invention

[0007] To address the shortcomings of existing technologies, such as the inability to locate resistance changes due to segmented resistance measurements without moving the switch and low testing efficiency, this invention provides a device and method for segmented resistance testing and temperature rise testing of switch cabinet main circuits.

[0008] The present invention adopts the following technical solution.

[0009] This invention discloses a device for segmented resistance testing and temperature rise testing of the main circuit of a switchgear, comprising a high-current generator, a three-phase disconnect switch, the main circuit of the switchgear, an automatic resistance inspection module, a temperature rise acquisition instrument, a main control console, and a circuit resistance meter.

[0010] The output terminal of the high current generator is connected to the input terminal of the three-phase disconnect switch; the three-phase disconnect switch is closed during the temperature rise test, and its output terminal is connected to the main circuit input terminal of the switch cabinet; the three phases of the main circuit output terminal of the switch cabinet are short-circuited.

[0011] The temperature / resistance measuring terminal of the automatic resistance inspection module is connected to a preset position in the main circuit of the switch cabinet; the temperature output terminal is connected to the temperature acquisition terminal of the temperature rise acquisition instrument; the first terminal of the segmented resistance test of the automatic resistance inspection module is connected to the positive terminal of the measurement voltage of the loop resistance meter; the second terminal of the segmented resistance test is connected to the negative terminal of the measurement voltage of the loop resistance meter.

[0012] The positive terminal of the current source of the circuit resistor is connected to the resistance test input terminal of the main circuit of the switch cabinet; the negative terminal of the current source is connected to the resistance test output terminal of the main circuit of the switch cabinet.

[0013] When testing the main circuit resistance of the switchgear, the host console sends a current source start signal to the circuit resistance meter communication port through the first communication port to control the current source in the circuit resistance meter to start. When conducting a temperature rise test, the host console sends a temperature measurement circuit connection signal to the automatic resistance inspection module communication port through the control signal output terminal to control the automatic resistance inspection module to connect the temperature measurement circuit, so that the temperature rise acquisition instrument can collect the temperature rise at the preset position through the temperature output terminal. When conducting a segmented resistance test, the host console sends a current source start signal to the circuit resistance meter communication port through the first communication port; and sends a resistance measurement circuit connection signal to the automatic resistance inspection module communication port through the control signal output terminal to control the automatic resistance inspection module to connect the segmented resistance measurement circuit.

[0014] More preferably,

[0015] Each phase in the main circuit of the switch cabinet has multiple preset positions.

[0016] More preferably,

[0017] The resistance measurement circuit connection signal includes a first resistance measurement circuit connection sub-signal, a second resistance measurement circuit connection sub-signal, and a third resistance measurement circuit connection sub-signal;

[0018] The first resistance measurement circuit connection sub-signal is used to control the segmented resistance measurement circuit of phase A of the main circuit of the connected switch cabinet;

[0019] The second resistance measurement circuit connection sub-signal is used to control the segmented resistance measurement circuit of phase B of the main circuit of the connected switch cabinet;

[0020] The third resistance measurement circuit connection sub-signal is used to control the segmented resistance measurement circuit of phase C of the main circuit of the connected switch cabinet.

[0021] More preferably,

[0022] The automatic resistance inspection module includes thermocouples and relays in a number equal to the preset positions in the main circuit of the switchgear;

[0023] Each thermocouple's working end serves as a temperature / resistance measuring terminal of the automatic resistance inspection module, corresponding to a preset position in the main circuit of a switchgear; the compensation terminal serves as a temperature output terminal of the automatic resistance inspection module; any electrode wire of each thermocouple is disconnected, with the disconnection point connected to the working end connected to the stationary contact of the corresponding relay, and the disconnection point connected to the compensation terminal connected to the normally open moving contact of the corresponding relay; the normally closed moving contact of the relay is connected to either the first terminal or the second terminal of the segmented resistance test; for each phase in the main circuit of the switchgear, there is one and only one normally closed moving contact of the relay corresponding to the preset position connected to the second terminal of the segmented resistance test.

[0024] When the communication port of the automatic resistance inspection module receives the connection signal of the temperature measurement circuit, it controls the static contacts of each relay to connect with the normally open moving contacts to form a complete thermocouple temperature measurement circuit.

[0025] When the communication port of the automatic resistance inspection module receives the first / second / third resistance measurement circuit connection signal, it controls the normally closed moving contact of the corresponding A phase / B phase / C to connect with the stationary contact and normally closed moving contact of the relay connected to the second terminal of the segmented resistance test; and controls the normally closed moving contact of the corresponding A phase / B phase / C to connect with the stationary contact and normally closed moving contact of the relay connected to the first terminal of the segmented resistance test in a preset sequence.

[0026] More preferably,

[0027] The test switchgear main circuit resistance includes the total resistance value of phase A of the main circuit of the switchgear, the total resistance value of phase B of the main circuit of the switchgear, and the total resistance value of phase C of the main circuit of the switchgear.

[0028] After the main circuit resistance test of the switchgear is completed, the loop resistance meter transmits the obtained loop resistance value to the host control console; the loop resistance value includes the total resistance value of phases A, B and C of the main circuit of the switchgear.

[0029] More preferably,

[0030] When measuring the total resistance of any phase in the main circuit of the switchgear, the input terminal of the phase under test is used as the resistance test input / output terminal of the main circuit of the switchgear, and the input terminal of any one of the remaining two phases is used as the resistance test output / input terminal of the main circuit of the switchgear, forming a current loop. At the same time, the voltage drop between the input and output terminals of the phase under test is collected. Based on the current amplitude output by the current source of the loop resistance meter and the voltage drop between the input and output terminals of the phase under test, the total resistance value of the phase under test is calculated.

[0031] More preferably,

[0032] When performing segmented resistance testing on a certain phase, the main control console sends a current source start signal to the loop resistance meter communication port through the first communication port, and sends a resistance measurement circuit connection signal corresponding to the phase to the automatic resistance inspection module communication port through the control signal output terminal, so as to perform segmented resistance testing on the phase.

[0033] After the segmented resistance test is completed, the host console receives the segmented resistance values ​​fed back by the loop resistance meter through the first communication port. By comparing these values ​​with the pre-measured segmented resistance values ​​of the phase, the location of the resistance change is determined.

[0034] Another aspect of the present invention discloses a method for segmented testing of the main circuit resistance and temperature rise of a switchgear based on a switchgear main circuit resistance segmented testing and temperature rise testing device, comprising:

[0035] After disconnecting the power supply to the high current generator and opening the three-phase disconnect switch, the main control console sends a current source start signal to the loop resistance meter to control the current source in the loop resistance meter to start, and receives the loop resistance value fed back by the loop resistance meter after completing the main loop resistance test of the switch cabinet.

[0036] After completing the main circuit resistance test of the switchgear, close the three-phase disconnect switch to connect the power supply of the high current generator. The main control console sends a temperature measurement circuit connection signal to the automatic resistance inspection module to control the automatic resistance inspection module to connect the temperature measurement circuit. The temperature rise acquisition instrument collects the temperature rise at a preset position in the main circuit of the switchgear through the automatic resistance inspection module.

[0037] After disconnecting the power supply to the high current generator again and opening the three-phase disconnect switch, the main control console sends a current source start signal to the loop resistance meter, and receives the loop resistance value fed back by the loop resistance meter after completing the main circuit resistance test of the switch cabinet. The main control console determines whether the resistance value of each phase in the main circuit of the switch cabinet has changed by comparing the loop resistance values ​​received after the two tests of the main circuit resistance of the switch cabinet.

[0038] The main control console sends a current source start signal to the loop resistor meter and a resistance measurement circuit connection signal to the automatic resistance inspection module to perform segmented resistance testing on the main circuit of the switch cabinet.

[0039] After the segmented resistance test is completed, the main control console receives the resistance values ​​of each segment from the loop resistance meter. By comparing these values ​​with the pre-measured resistance values ​​of each segment, the location of the resistance change is determined.

[0040] Another aspect of this application discloses a terminal, including a processor and a storage medium;

[0041] The storage medium is used to store instructions;

[0042] The processor is used to operate according to the instructions to execute the test methods for segmented resistance testing and temperature rise testing of the main circuit of the switchgear as described above.

[0043] This application also discloses a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for segmented resistance testing and temperature rise testing of the main circuit of the switchgear.

[0044] The beneficial effects of this invention are compared with those of the prior art:

[0045] By using the two thermocouple wires of the thermocouple used for temperature rise testing as leads for resistance measurement, and integrating a resistance testing power supply, the main circuit resistance is measured in segments. This avoids the defect that the resistance change cannot be measured in segments after the switch temperature rise test, which would cause the resistance change to be unlocatable, and realizes the automated testing function of resistance segment measurement.

[0046] This invention integrates two devices for main circuit resistance testing and temperature rise testing. Controlled by a console, resistance is measured automatically without human intervention. When thermocouple signals and circuit resistance voltage signals are multiplexed, the signal wiring on the switchgear side becomes much simpler. Furthermore, when testing circuit resistance, there is no need to switch voltage lines; a single current return can complete the contact resistance test of all points in both phase circuits, thus significantly improving testing efficiency. The simplified test wiring also reduces human error during the testing process.

[0047] Furthermore, the present invention also has the following outstanding advantages:

[0048] 1. This invention integrates main circuit resistance testing and temperature rise testing into one device, laying the foundation for automated testing;

[0049] 2. Before and after the temperature rise test, the circuit resistance can be automatically measured in segments using pre-embedded thermocouples;

[0050] 3. The resistance of the above test circuits can be compared and analyzed to pinpoint the location of resistance changes;

[0051] 4. The above tests are automated, requiring no human intervention, which improves testing efficiency and accuracy, and avoids human error;

[0052] 5. This invention is very useful for analyzing resistance changes before and after temperature rise tests in new product development, avoiding inaccurate testing caused by actions or movement of the test sample. Attached Figure Description

[0053] Figure 1 This is a circuit connection diagram of the switch cabinet main circuit resistance segment test and temperature rise test device. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this invention. The embodiments described in this application are merely some embodiments of this invention, and not all embodiments. Based on the spirit of this invention, other embodiments obtained by those skilled in the art without creative effort are all within the protection scope of this invention.

[0055] This application discloses a device for segmented resistance testing and temperature rise testing of the main circuit of a switchgear. (See attached document) Figure 1It includes a high current generator, switch cabinet main circuit, automatic resistance inspection module, temperature rise acquisition instrument, host control console and loop resistance meter.

[0056] The high-current generator is powered on only during the temperature rise test, providing a high current to the main circuit of the switchgear. The output terminal of the high-current generator is connected to the input terminal of the three-phase disconnect switch. The three-phase disconnect switch is closed during the temperature rise test and not closed when the temperature rise test is not performed. Its output terminal is connected to the input terminal of the main circuit of the switchgear (the stationary contact of phase A of the three-phase disconnect switch is connected to the output terminal A of the high-current generator, the stationary contact of phase B is connected to the output terminal B of the high-current generator, and the stationary contact of phase C is connected to the output terminal C of the high-current generator; the output terminals of phases A, B, and C of the three-phase disconnect switch are connected to the input terminals of phases A, B, and C of the main circuit of the switchgear). The three phases of the output terminals of the main circuit of the switchgear are short-circuited. Specifically, when it is necessary to test the resistance of the main circuit of the switchgear, the power supply of the high-current generator is cut off, and then the disconnect switch is opened. When it is necessary to test the temperature rise test, the disconnect switch is closed first, and then the power supply of the high-current generator is connected. The segmented resistance test is performed after the second resistance test of the main circuit of the switchgear, or simultaneously with the second resistance test of the main circuit of the switchgear.

[0057] The three-phase short circuit at the outgoing terminals of the main circuit of the switchgear can be achieved by shorting the copper busbar / isolating switch. The shorting copper busbar / isolating switch here is only closed when the high-voltage switchgear is opened for temperature rise test, and is opened when the high-voltage switchgear is not opened for temperature rise test, so that the switchgear can work normally.

[0058] The temperature / resistance measuring terminal of the automatic resistance inspection module is connected to a preset position in the main circuit of the switch cabinet; the temperature output terminal is connected to the temperature acquisition terminal of the temperature rise acquisition instrument; the first terminal of the segmented resistance test of the automatic resistance inspection module is connected to the positive terminal of the measurement voltage of the loop resistance meter; the second terminal of the segmented resistance test is connected to the negative terminal of the measurement voltage of the loop resistance meter; each phase in the main circuit of the switch cabinet has multiple preset positions.

[0059] The automatic resistance inspection module includes thermocouples and relays in a number equal to the preset positions in the main circuit of the switchgear;

[0060] The working end of each thermocouple serves as a temperature / resistance measuring terminal of the automatic resistance inspection module, corresponding to a preset position in the main circuit of a switch cabinet. Figure 1 The arrows between phase A of the main circuit of the switchgear and the working ends of each thermocouple indicate that the working ends of each thermocouple are physically attached to the preset positions of the main circuit of the switchgear, which is achieved by pre-embedding thermocouples. Figure 1This is for illustrative purposes only. The thermocouples connected to relays 4-60 of phase A for phases B and C are not shown in the diagram (in reality, thermocouples of the same specification are also pre-embedded at the corresponding positions of phases B and C). The compensation end of each thermocouple serves as a temperature output end of the automatic resistance inspection module. Any electrode wire of each thermocouple is disconnected, and the disconnection point of the working end is connected to the stationary contact of the corresponding relay, while the disconnection point of the compensation end is connected to the normally open moving contact of the corresponding relay. The normally closed moving contact of the relay is connected to the first or second end of the segmented resistance test. For each phase in the main circuit of the switchgear, there is one and only one normally closed moving contact of the relay corresponding to a preset position connected to the second end of the segmented resistance test. In a preferred embodiment of the present invention, the preset position corresponding to the relay whose normally closed moving contact is connected to the second end of the segmented resistance test is the preset position closest to the main circuit inlet of the switchgear in each phase.

[0061] When the communication port of the automatic resistance inspection module receives the connection signal of the temperature measurement circuit, it controls each relay to switch to the normally open position, and the stationary contact is connected with the normally open moving contact to form a complete thermocouple temperature measurement circuit.

[0062] When the automatic resistance inspection module receives the first resistance measurement circuit connection signal at its communication port, it controls the normally closed moving contact corresponding to A and the relay connected to the second terminal of the segmented resistance test to switch to the normally closed position, connecting the stationary contact with the normally closed moving contact; and controls the normally closed moving contact corresponding to A and the stationary contact with the normally closed moving contact of the relay connected to the first terminal of the segmented resistance test to connect in a preset sequence. The preset sequence can be set by those skilled in the art according to actual conditions, and will not be elaborated here.

[0063] When the communication port of the automatic resistance inspection module receives the second resistance measurement circuit connection signal, it controls the normally closed moving contact corresponding to B and the relay connected to the second terminal of the segmented resistance test to switch to the normally closed position, connecting the stationary contact with the normally closed moving contact; and controls the normally closed moving contact corresponding to B and the stationary contact with the normally closed moving contact of the relay connected to the first terminal of the segmented resistance test to connect in a preset sequence. The preset sequence can be set by those skilled in the art according to the actual situation, and will not be elaborated here.

[0064] When the communication port of the automatic resistance inspection module receives the signal indicating connection to the third resistance measurement circuit, it controls the normally closed moving contact corresponding to C and the relay connected to the second terminal of the segmented resistance test to switch to the normally closed position, connecting the stationary contact with the normally closed moving contact; and controls the normally closed moving contact corresponding to C and the stationary contact with the normally closed moving contact of the relay connected to the first terminal of the segmented resistance test to connect in a preset sequence. The preset sequence can be set by those skilled in the art according to actual conditions, and will not be elaborated here.

[0065] At any given moment, there are only two relays with stationary contacts connected to normally closed moving contacts: one is a relay with its normally closed moving contact connected to the second terminal of the segmented resistance test; the other is a relay with its normally closed moving contact connected to the first terminal of the segmented resistance test. Taking phase A as an example, at any given moment, only relays 3 and 4 are open to the normally closed position (other relays are open to the normally open position), or relays 3 and 5 are open to the normally closed position (other relays are open to the normally open position), ..., or relays 3 and 60 are open to the normally closed position (other relays are open to the normally open position).

[0066] The positive terminal of the current source of the loop resistance meter is connected to the resistance test input terminal of the main circuit of the switchgear; the negative terminal of the current source is connected to the resistance test output terminal of the main circuit of the switchgear. The loop resistance meter is a specialized instrument used to measure the contact resistance and loop resistance of switching equipment in a power system to ensure the safe operation of the equipment. Specifically, when the loop resistance meter is powered by a current source, it calculates the resistance to be measured based on Ohm's law by detecting the voltage drop between the two phases of the resistor under test.

[0067] After the main circuit resistance test / segment resistance test of the switch cabinet is completed, the loop resistance meter will feed back the measured resistance value to the first communication port of the host control console through the loop resistance meter communication port;

[0068] When testing the main circuit resistance of the switchgear, the host control console sends a current source start signal to the loop resistance meter communication port through the first communication port to control the current source in the loop resistance meter to start. The loop resistance meter calculates the resistance to be measured by detecting the voltage drop between the two ends of the resistor to be measured according to Ohm's law, and feeds back the obtained loop resistance value to the first communication port of the host control console through the loop resistance meter communication port. Those skilled in the art should know the specific form of the current source start signal required by the loop resistance meter, which will not be described here.

[0069] The test switchgear main circuit resistance includes the total resistance value of phase A of the main circuit, the total resistance value of phase B of the main circuit, and the total resistance value of phase C of the main circuit.

[0070] When measuring the total resistance of any phase in the main circuit of a switchgear, that phase is designated as the phase under test. The input terminal of the phase under test is used as the resistance test input / output terminal of the main circuit. The input terminal of any one of the remaining two phases is used as the resistance test output / input terminal of the main circuit, forming a current loop. Simultaneously, the voltage drop between the input and output terminals of the phase under test is collected. Based on the current amplitude output by the loop resistance meter's current source and the voltage drop between the input and output terminals of the phase under test, the total resistance value of the phase under test is calculated. Specifically, this includes:

[0071] When testing the total resistance of phase A and / or phase B of the main circuit of the switchgear, the input terminal of phase A of the main circuit can be used as the resistance test input terminal, and the input terminal of phase B as the resistance test output terminal. Alternatively, the input terminal of phase B can be used as the resistance test input terminal, and the input terminal of phase A as the resistance test output terminal, forming a current loop. Then, the voltage drop between the input and output terminals of phase A and / or phase B of the main circuit is collected. This data collection can be achieved using a multimeter, voltage sensor, etc., and the collected voltage drop is transmitted to the loop resistance meter via its communication port. Alternatively, when measuring the total resistance of phase A, a signal indicating that the phase A total resistance measurement circuit is connected is sent from the main control console to the automatic resistance inspection module, controlling the automatic resistance inspection module to activate the relay corresponding to the preset position at the input terminal of phase A (i.e.,...). Figure 1 The relay 3) and the relay corresponding to the preset position at the A-phase outgoing terminal (i.e., the relay 3) Figure 1 Relay 60 is switched to the normally closed position, while other relays are switched to the normally open position. This allows the voltage drop between the input and output terminals of phase A to be measured via the positive and negative terminals of the loop resistance meter. When measuring the total resistance of phase B, the main control console sends a phase B total resistance measurement circuit connection signal to the automatic resistance inspection module. This controls the automatic resistance inspection module to switch the relays at preset positions at the input and output terminals of phase B to the normally closed position, while the other relays are switched to the normally open position. This allows the loop resistance meter to measure the voltage drop between the input and output terminals of phase B. The loop resistance meter uses Ohm's law, based on the current amplitude output from the loop resistance meter's current source, and the voltage drop between the input and output terminals of the phase under test, to calculate the total resistance value of phase A and / or the total resistance value of phase B in the main circuit of the switchgear. Those skilled in the art should be able to set the phase A total resistance measurement circuit connection signal and the phase B total resistance measurement circuit connection signal according to actual conditions; this will not be elaborated here.

[0072] Similarly, when testing the total resistance of phase A and / or phase C of the main circuit of the switchgear, the input terminal of phase A of the main circuit can be used as the resistance test input terminal, and the input terminal of phase C as the resistance test output terminal. Alternatively, the input terminal of phase C can be used as the resistance test input terminal, and the input terminal of phase A as the resistance test output terminal, forming a current loop. Then, the voltage drop between the input and output terminals of phase A and / or phase C of the main circuit can be collected. This collection can be achieved using a multimeter, voltage sensor, etc., and the collected voltage drop can be transmitted to the loop resistance meter via the communication port. Alternatively, using the aforementioned method, when measuring the total resistance of phase A, the main control... The control panel sends a signal to the automatic resistance inspection module to connect the A-phase total resistance measurement circuit. The voltage drop between the A-phase input and output terminals is measured using the positive and negative terminals of the loop resistance meter. When measuring the total resistance of phase C, the control panel sends a signal to the automatic resistance inspection module to connect the C-phase total resistance measurement circuit. This controls the automatic resistance inspection module to set the relays at preset positions at the C-phase input and output terminals to their normally closed positions, and the other relays to their normally open positions. This allows the loop resistance meter to measure the voltage drop between the C-phase input and output terminals. The loop resistance meter uses Ohm's law, based on the current amplitude output from its current source and the voltage drop between the input and output terminals of the phase under test, to calculate the total resistance value of phase A in the main circuit of the switchgear and / or the total resistance value of phase C in the main circuit of the switchgear. Those skilled in the art should be able to set the C-phase total resistance measurement circuit connection signal according to actual conditions; this will not be elaborated here.

[0073] Similarly, when testing the total resistance of phase B and / or phase C of the main circuit of the switchgear, the input terminal of phase B of the main circuit can be used as the resistance test input terminal, and the input terminal of phase C of the main circuit can be used as the resistance test output terminal. Alternatively, the input terminal of phase C of the main circuit can be used as the resistance test input terminal, and the input terminal of phase B of the main circuit can be used as the resistance test output terminal, forming a current loop. Then, the voltage drop between the input and output terminals of phase B and / or phase C of the main circuit can be collected. This collection can be achieved using a multimeter, voltage sensor, etc., and the collected voltage drop is transmitted to the loop resistance meter via the communication port. The measurement is implemented in the resistance meter, or, using the aforementioned method, when measuring the total resistance of phase B, a signal indicating the connection of the phase B total resistance measurement circuit is sent to the automatic resistance inspection module via the host console. The voltage drop between the input and output terminals of phase B is measured using the positive and negative terminals of the loop resistance meter. When measuring the total resistance of phase C, a signal indicating the connection of the phase C total resistance measurement circuit is sent to the automatic resistance inspection module via the host console. The voltage drop between the input and output terminals of phase C is measured using the positive and negative terminals of the loop resistance meter. The loop resistance meter uses Ohm's law, based on the current amplitude output by the loop resistance meter's current source, and the voltage drop between the input and output terminals of the phase under test, to calculate the total resistance value of phase B of the main circuit of the switchgear and / or the total resistance value of phase C of the main circuit of the switchgear.

[0074] Those skilled in the art can choose the method for testing the total resistance value of phases A, B, and C of the main circuit of the switchgear according to the actual situation. For example, the input terminal of phase A of the main circuit can be used as the resistance test input terminal, and the input terminal of phase B of the main circuit can be used as the resistance test output terminal to test the total resistance value of phases A and B of the main circuit. Then, the input terminal of phase A of the main circuit can be used as the resistance test input terminal, and the input terminal of phase C of the main circuit can be used as the resistance output terminal. The test output terminal measures the total resistance of phase C of the main circuit of the switchgear; alternatively, the input terminal of phase B of the main circuit can be used as the resistance test input terminal, and the input terminal of phase C of the main circuit can be used as the resistance test output terminal to test the total resistance of phases B and C of the main circuit. Then, the input terminal of phase A of the main circuit can be used as the resistance test input terminal, and the input terminal of phase C of the main circuit can be used as the resistance test output terminal to test the total resistance of phase A of the main circuit, etc.

[0075] This invention can achieve the switching of the resistance test input terminal and the resistance test output terminal of the main circuit of the switchgear using switching components such as relays and circuit breakers. For example, each phase input terminal is connected to the first terminal of two relays; the second terminal of one relay is connected to the resistance test input terminal of the main circuit of the switchgear, and the second terminal of the other relay is connected to the resistance test output terminal of the main circuit of the switchgear. That is, the resistance test input terminal and the resistance test output terminal of the main circuit of the switchgear are respectively connected to the second terminals of three relays (there are a total of six relays whose first terminals are connected to the input terminals of phases A, B, and C; as described above, the second terminals of three of these relays are connected to the resistance test input terminal of the main circuit of the switchgear, and the other three are connected to the resistance test output terminal of the main circuit of the switchgear); the appendix of this invention... Figure 1 This is for illustrative purposes only; this part is not included. Figure 1 This is reflected in the text.

[0076] After the main circuit resistance test of the switchgear is completed, the loop resistance meter transmits the obtained loop resistance value to the host control console. The loop resistance value includes the total resistance value of phase A, phase B, and phase C of the main circuit of the switchgear. After the second test of the main circuit resistance of the switchgear, the host control console compares the loop resistance values ​​received after the two tests to determine whether the resistance values ​​of each phase in the main circuit of the switchgear have changed.

[0077] During the temperature rise test, the main control console sends a temperature measurement circuit connection signal to the communication port of the automatic resistance inspection module through the control signal output terminal, controlling the automatic resistance inspection module to connect the temperature measurement circuit, so that the temperature rise acquisition instrument can collect the temperature rise at each preset position through the temperature output terminal; those skilled in the art should be able to set the temperature measurement circuit connection signal according to the actual situation, which will not be elaborated here.

[0078] During segmented resistance testing, the host console sends a current source start signal to the loop resistance meter communication port via the first communication port, controlling the current source in the loop resistance meter to start. It also sends a resistance measurement circuit connection signal to the automatic resistance inspection module communication port via the control signal output terminal, controlling the automatic resistance inspection module to connect the segmented resistance measurement circuit. After the current source starts, the loop resistance meter collects the voltage drop between the first and second terminals of the resistance test (i.e., the voltage drop between the two ends of the segmented resistance being tested) by measuring the positive and negative voltage terminals. Using Ohm's law, it calculates the segmented resistance value and feeds it back to the host console via the loop resistance meter communication port, thus realizing the segmented resistance test. The current source start signal can be set by those skilled in the art according to the actual situation, and will not be elaborated here. The resistance measurement circuit connection signal includes a first resistance measurement circuit connection sub-signal, a second resistance measurement circuit connection sub-signal, and a third resistance measurement circuit connection sub-signal.

[0079] The first resistance measurement circuit connection sub-signal is used to control the segmented resistance measurement circuit of phase A of the main circuit of the switch cabinet; the first resistance measurement circuit connection sub-signal can be set by those skilled in the art according to the actual situation, and will not be elaborated here.

[0080] The second resistance measurement circuit connection sub-signal is used to control the segmented resistance measurement circuit of phase B of the main circuit of the switch cabinet; the second resistance measurement circuit connection sub-signal can be set by those skilled in the art according to the actual situation, and will not be elaborated here.

[0081] The third resistance measurement circuit connection sub-signal is used to control the segmented resistance measurement circuit of phase C of the main circuit of the switchgear. The third resistance measurement circuit connection sub-signal can be set by those skilled in the art according to the actual situation, and will not be elaborated here.

[0082] At any given time, only one of the resistance measurement circuit connection sub-signals is sent to connect the segmented resistance measurement circuits of the corresponding phase. The first resistance measurement circuit connection sub-signal, the second resistance measurement circuit connection sub-signal, and the third resistance measurement circuit connection sub-signal are sent in a preset timing sequence. Those skilled in the art should be able to set the preset timing sequence according to the actual situation, which will not be elaborated here.

[0083] When measuring the segmented resistance value of any phase in the main circuit of the switchgear, the input terminal of the phase to be measured is used as the resistance test input / output terminal of the main circuit of the switchgear, and the input terminal of any one of the remaining two phases is used as the resistance test output / input terminal of the main circuit of the switchgear, forming a current loop. At the same time, the loop resistance meter collects the voltage drop between the first resistance test terminal and the second resistance test terminal by measuring the positive and negative voltage terminals. Based on the current amplitude output by the current source of the loop resistance meter and the voltage drop between the first resistance test terminal and the second resistance test terminal, the segmented resistance value is calculated.

[0084] When performing segmented resistance testing on a certain phase, the main control console sends a current source start signal to the loop resistance meter communication port through the first communication port, and sends a resistance measurement circuit connection signal corresponding to the phase to the automatic resistance inspection module communication port through the control signal output terminal, so as to perform segmented resistance testing on the phase.

[0085] After the segmented resistance test is completed, the host console receives the segmented resistance values ​​(e.g., ...) fed back by the loop resistance meter through the first communication port. Figure 1As shown, taking phase A as an example, the segmented resistance values ​​fed back by the resistor meter in the first communication port include the segmented resistance value between the preset position corresponding to relay 3 and the preset position corresponding to relay 4 (hereinafter referred to as the first resistance value), the segmented resistance value between the preset position corresponding to relay 3 and the preset position corresponding to relay 5 (hereinafter referred to as the second resistance value), ..., the segmented resistance value between the preset position corresponding to relay 3 and the preset position corresponding to relay 60 (hereinafter referred to as the fifty-seventh resistance value). The present invention can also obtain the segmented resistance value between every two adjacent preset points in phase A by subtracting the first resistance value from the second resistance value, subtracting the second resistance value from the third resistance value, ..., subtracting the fifty-seventh resistance value from the fifty-sixth resistance value. By comparing the received segmented resistance values ​​with the pre-measured segmented resistance values ​​of the phase, the position of resistance change is determined.

[0086] In a preferred embodiment of the present invention, the segmented resistance test and the second main circuit resistance test of the switchgear can be performed simultaneously. When performing the segmented resistance test and the second main circuit resistance test of the switchgear simultaneously, the power supply of the high current generator needs to be cut off, then the isolating switch K1 needs to be opened, and then the host control console sends a current source start signal to the loop resistance meter and a resistance measurement circuit connection signal to the automatic resistance inspection module. Taking phase A as an example, after measuring the segmented resistance of phase A, the fifty-seventh resistance value can be directly used as the total resistance value of phase A, so as to achieve the effect of simultaneously measuring the segmented resistance and the total resistance of phase A. The same applies to phases B and C, and will not be described in detail here.

[0087] This application also discloses a method for segmented resistance testing and temperature rise testing of the main circuit of a switchgear based on the aforementioned switchgear main circuit resistance segmented testing and temperature rise testing device, including:

[0088] After disconnecting the power supply to the high current generator and opening the three-phase disconnect switch, the main control console sends a current source start signal to the loop resistance meter to control the current source in the loop resistance meter to start, and receives the loop resistance value fed back by the loop resistance meter after completing the main loop resistance test of the switch cabinet.

[0089] After completing the main circuit resistance test of the switchgear, close the three-phase disconnect switch to connect the power supply of the high current generator. The main control console sends a temperature measurement circuit connection signal to the automatic resistance inspection module to control the automatic resistance inspection module to connect the temperature measurement circuit. The temperature rise acquisition instrument collects the temperature rise at a preset position in the main circuit of the switchgear through the automatic resistance inspection module.

[0090] After disconnecting the power supply to the high current generator again and opening the three-phase disconnect switch, the main control console sends a current source start signal to the loop resistance meter, and receives the loop resistance value fed back by the loop resistance meter after completing the main circuit resistance test of the switch cabinet. The main control console determines whether the resistance value of each phase in the main circuit of the switch cabinet has changed by comparing the loop resistance values ​​received after the two tests of the main circuit resistance of the switch cabinet.

[0091] The main control console sends a current source start signal to the loop resistor meter and a resistance measurement circuit connection signal to the automatic resistance inspection module to perform segmented resistance testing on the main circuit of the switch cabinet.

[0092] After the segmented resistance test is completed, the main control console receives the resistance values ​​of each segment from the loop resistance meter. By comparing these values ​​with the pre-measured resistance values ​​of each segment, the location of the resistance change is determined.

[0093] Example 1

[0094] A device for segmented resistance testing and temperature rise testing of main circuit of switchgear, such as Figure 1 As shown, it includes a high current generator, a three-phase disconnect switch, a switch cabinet main circuit, an automatic resistance inspection module, a temperature rise acquisition instrument, a main control console, and a loop resistance meter.

[0095] First, the resistance of the main circuit of the switchgear is tested. After the main circuit resistance test is completed, a temperature rise test is performed. After the temperature rise test is completed, the resistance of the main circuit of the switchgear is tested again. Based on the results of the two tests, it is determined whether there is a change in the resistance value of one or more phases in the main circuit of the switchgear. The segmented resistance values ​​are also tested. By comparing them with the pre-determined segmented resistance values, the location of the resistance change is determined.

[0096] During the temperature rise test, the high-current generator supplies a large current to the main circuit of the switchgear. First, the three-phase circuits A, B, and C of the main circuit are connected together as a short-circuit point for the temperature rise test, forming a three-phase short circuit. Next, the three-phase isolating switch K1, connecting the main circuit of the switchgear to the high-current generator, is closed to form a current loop. Simultaneously, a signal indicating the temperature measurement circuit is connected is sent from the main control console to the communication port of the automatic resistance monitoring module. Figure 1 The relays 1-60 shown are switched from the normally closed position to the normally open position (due to...) Figure 1 This is for illustrative purposes only. The thermocouples connected to relays 4-60 of phase A for phase B and phase C are not shown in the diagram. In reality, thermocouples of the same specification are also pre-embedded at the corresponding positions of phase B and phase C. The pre-embedded thermocouples at the corresponding positions of phase B and phase C are also switched from the normally closed position to the normally open position at this time. At this time, the thermocouple circuit is connected, and the temperature rise acquisition instrument outputs the temperature rise of the main circuit of the switch cabinet.

[0097] When testing the main circuit resistance of the switchgear, disconnect the power supply to the high current generator and then open the isolating switch K1. Connect the positive terminal of the current source of the loop resistance meter to phase A of the main circuit of the switchgear, and the negative terminal to phase C of the main circuit of the switchgear (the connection point between phases A and C is the end of the main circuit of the switchgear that is not short-circuited). At this time, the current source of the loop resistance meter returns to the negative terminal (I-) of the current source of the loop resistance meter through phase A of the main circuit of the switchgear, the temperature rise short-circuit point of the main circuit of the switchgear, and phase C of the main circuit of the switchgear. The current loop is completed, and the conditions for applying current are met. The host control console sends a current source start signal to the communication port of the loop resistance meter through the first communication port to control the current source in the loop resistance meter to start. The loop resistance meter measures the total resistance value of phase A and phase C of the main circuit of the switchgear. The same principle can be used to measure the total resistance value of phase B of the main circuit of the switchgear. After measuring all the above total resistances, the loop resistance meter uses all the above total resistances as the loop resistance value obtained by the test and feeds back the loop resistance value obtained by the test to the first communication port of the host control console through the loop resistance meter communication port. After the second test of the main circuit resistance of the switchgear, the main control console compares the circuit resistance values ​​received after the two tests to determine whether the resistance values ​​of each phase in the main circuit of the switchgear have changed.

[0098] The main control console sends a current source start signal to the loop resistance meter and sends the first, second, and third resistance circuit connection signals to the automatic resistance inspection module in a preset timing sequence to perform segmented resistance testing on the main circuit resistance of the switchgear. When measuring the segmented resistance of phase A of the main circuit of the switchgear, the main control console sends a command to the communication port of the automatic resistance inspection module to switch relays 3 to 60 from the normally open position to the normally closed position in a preset relay connection sequence. The positive terminal (U+) of the loop resistance meter is connected to phase A of the main circuit of the switchgear through relays 4, 5, ... or relay 60 and their respective connected single thermocouple wires. Through phase A and the single thermocouple wire connected to relay 3, relay 3 is connected in series with the negative terminal (U-) of the loop resistance meter, forming a measurement voltage loop.

[0099] When relays 4 and 3 are both switched to the normally closed position, the positive terminal of the measuring voltage of relay 4 and the negative terminal of the measuring voltage of relay 3 form a measuring voltage circuit. Current flows through the main circuit of the switch cabinet. According to Ohm's law, the resistance value between relays 3 and 4 can be calculated, thus completing the test of a segment resistance in the main circuit.

[0100] Similarly, when relay 5 or relay 6, along with relay 3, are simultaneously switched to the normally closed position, relays 5 and 6, which are connected to the positive terminal of the voltage measurement circuit, can form a circuit with relay 3, which is connected to the negative terminal of the voltage measurement circuit in phase A of the switch cabinet, thus allowing the measurement of the segment resistances of phase A. The segment resistance test has already been completed on phase A.

[0101] The segmented resistance of phases B and C can be measured based on the above process.

[0102] In summary, this invention integrates two devices for measuring resistance and temperature rise, and automatically measures resistance through control of a console.

[0103] This disclosure can be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of this disclosure.

[0104] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination of the foregoing. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0105] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0106] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A device for segmented resistance testing and temperature rise testing of the main circuit of a switchgear, characterized in that, Includes a high-current generator, three-phase disconnect switch, main circuit of switchgear, automatic resistance monitoring module, temperature rise acquisition instrument, main control console, and loop resistance meter: The output terminal of the high current generator is connected to the input terminal of the three-phase disconnect switch; the three-phase disconnect switch is closed during the temperature rise test, and its output terminal is connected to the main circuit input terminal of the switch cabinet; the three phases of the main circuit output terminal of the switch cabinet are short-circuited. The temperature / resistance measuring terminal of the automatic resistance inspection module is connected to a preset position in the main circuit of the switch cabinet; the temperature output terminal is connected to the temperature acquisition terminal of the temperature rise acquisition instrument; the first terminal of the segmented resistance test of the automatic resistance inspection module is connected to the positive terminal of the measurement voltage of the loop resistance meter; the second terminal of the segmented resistance test is connected to the negative terminal of the measurement voltage of the loop resistance meter. The positive terminal of the current source of the circuit resistor is connected to the resistance test input terminal of the main circuit of the switch cabinet; the negative terminal of the current source is connected to the resistance test output terminal of the main circuit of the switch cabinet. When testing the main circuit resistance of the switchgear, the host console sends a current source start signal to the circuit resistance meter communication port through the first communication port to control the current source in the circuit resistance meter to start. When conducting a temperature rise test, the host console sends a temperature measurement circuit connection signal to the automatic resistance inspection module communication port through the control signal output terminal to control the automatic resistance inspection module to connect the temperature measurement circuit, so that the temperature rise acquisition instrument can collect the temperature rise at the preset position through the temperature output terminal. When conducting a segmented resistance test, the host console sends a current source start signal to the circuit resistance meter communication port through the first communication port, and sends a resistance measurement circuit connection signal to the automatic resistance inspection module communication port through the control signal output terminal to control the automatic resistance inspection module to connect the segmented resistance measurement circuit.

2. The switchgear main circuit resistance segmentation test and temperature rise test device according to claim 1, characterized in that: Each phase in the main circuit of the switch cabinet has multiple preset positions.

3. The switchgear main circuit resistance segmentation test and temperature rise test device according to claim 1, characterized in that: The resistance measurement circuit connection signal includes a first resistance measurement circuit connection sub-signal, a second resistance measurement circuit connection sub-signal, and a third resistance measurement circuit connection sub-signal; The first resistance measurement circuit connection sub-signal is used to control the segmented resistance measurement circuit of phase A of the main circuit of the connected switch cabinet; The second resistance measurement circuit connection sub-signal is used to control the segmented resistance measurement circuit of phase B of the main circuit of the connected switch cabinet; The third resistance measurement circuit connection sub-signal is used to control the segmented resistance measurement circuit of phase C of the main circuit of the connected switch cabinet.

4. The switchgear main circuit resistance segmentation test and temperature rise test device according to claim 1, 2, or 3, characterized in that: The automatic resistance inspection module includes thermocouples and relays in a number equal to the preset positions in the main circuit of the switchgear; Each thermocouple's working end serves as a temperature / resistance measuring terminal of the automatic resistance inspection module, corresponding to a preset position in the main circuit of a switchgear; the compensation terminal serves as a temperature output terminal of the automatic resistance inspection module; any electrode wire of each thermocouple is disconnected, with the disconnection point connected to the working end connected to the stationary contact of the corresponding relay, and the disconnection point connected to the compensation terminal connected to the normally open moving contact of the corresponding relay; the normally closed moving contact of the relay is connected to either the first terminal or the second terminal of the segmented resistance test; for each phase in the main circuit of the switchgear, there is one and only one normally closed moving contact of the relay corresponding to the preset position connected to the second terminal of the segmented resistance test. When the communication port of the automatic resistance inspection module receives the connection signal of the temperature measurement circuit, it controls the static contacts of each relay to connect with the normally open moving contacts to form a complete thermocouple temperature measurement circuit. When the communication port of the automatic resistance inspection module receives the first / second / third resistance measurement circuit connection signal, it controls the normally closed moving contact of the corresponding A phase / B phase / C to connect with the stationary contact and normally closed moving contact of the relay connected to the second terminal of the segmented resistance test; and controls the normally closed moving contact of the corresponding A phase / B phase / C to connect with the stationary contact and normally closed moving contact of the relay connected to the first terminal of the segmented resistance test in a preset sequence.

5. The switchgear main circuit resistance segmentation test and temperature rise test device according to claim 1, characterized in that: The test switchgear main circuit resistance includes the total resistance value of phase A of the main circuit of the switchgear, the total resistance value of phase B of the main circuit of the switchgear, and the total resistance value of phase C of the main circuit of the switchgear. After the main circuit resistance test of the switchgear is completed, the loop resistance meter transmits the obtained loop resistance value to the host control console; the loop resistance value includes the total resistance value of phases A, B and C of the main circuit of the switchgear.

6. The switchgear main circuit resistance segmentation test and temperature rise test device according to claim 1 or 5, characterized in that: When measuring the total resistance of any phase in the main circuit of the switchgear, the input terminal of the phase under test is used as the resistance test input / output terminal of the main circuit of the switchgear, and the input terminal of any one of the remaining two phases is used as the resistance test output / input terminal of the main circuit of the switchgear, forming a current loop. At the same time, the voltage drop between the input and output terminals of the phase under test is collected. Based on the current amplitude output by the current source of the loop resistance meter and the voltage drop between the input and output terminals of the phase under test, the total resistance value of the phase under test is calculated.

7. The switchgear main circuit resistance segmentation test and temperature rise test device according to claim 1 or 3, characterized in that: When performing segmented resistance testing on a certain phase, the main control console sends a current source start signal to the loop resistance meter communication port through the first communication port, and sends a resistance measurement circuit connection signal corresponding to the phase to the automatic resistance inspection module communication port through the control signal output terminal, so as to perform segmented resistance testing on the phase. After the segmented resistance test is completed, the host console receives the segmented resistance values ​​fed back by the loop resistance meter through the first communication port. By comparing these values ​​with the pre-measured segmented resistance values ​​of the phase, the location of the resistance change is determined.

8. A method for testing the resistance segmentation and temperature rise of the main circuit of a switchgear using the switchgear main circuit resistance segmentation test and temperature rise test device according to any one of claims 1-7, characterized in that: After disconnecting the power supply to the high current generator and opening the three-phase disconnect switch, the main control console sends a current source start signal to the loop resistance meter to control the current source in the loop resistance meter to start, and receives the loop resistance value fed back by the loop resistance meter after completing the main loop resistance test of the switch cabinet. After completing the main circuit resistance test of the switchgear, close the three-phase disconnect switch to connect the power supply of the high current generator. The main control console sends a temperature measurement circuit connection signal to the automatic resistance inspection module to control the automatic resistance inspection module to connect the temperature measurement circuit. The temperature rise acquisition instrument collects the temperature rise at a preset position in the main circuit of the switchgear through the automatic resistance inspection module. After disconnecting the power supply to the high current generator again and opening the three-phase disconnect switch, the main control console sends a current source start signal to the loop resistance meter, and receives the loop resistance value fed back by the loop resistance meter after completing the main circuit resistance test of the switch cabinet. The main control console determines whether the resistance value of each phase in the main circuit of the switch cabinet has changed by comparing the loop resistance values ​​received after the two tests of the main circuit resistance of the switch cabinet. The main control console sends a current source start signal to the loop resistor meter and a resistance measurement circuit connection signal to the automatic resistance inspection module to perform segmented resistance testing on the main circuit of the switch cabinet. After the segmented resistance test is completed, the main control console receives the resistance values ​​of each segment from the loop resistance meter. By comparing these values ​​with the pre-measured resistance values ​​of each segment, the location of the resistance change is determined.

9. A terminal, comprising a processor and a storage medium; characterized in that: The storage medium is used to store instructions; The processor is used to operate according to the instructions to execute the steps of the switch cabinet main circuit resistance segment test and temperature rise test method according to claim 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the switch cabinet main circuit resistance segment test and temperature rise test method as described in claim 8.

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