Insulation performance testing device and method for simulating rapid temperature rise process of superconducting magnet without quench mitigation

Abstract

The application relates to the technical field of superconducting magnet electrical safety and electric arc behavior evaluation, and discloses an insulation performance testing device for simulating a rapid temperature rising process of a superconducting magnet without quench relief, the insulation performance testing device comprising: a sample to be tested, which comprises a first conductor and a second conductor that are mutually insulated and isolated, and a conductor-to-conductor insulation layer arranged between the first conductor and the second conductor; a first testing module, which comprises a first electrode and a second electrode; and a second testing module, which comprises the first electrode and a third electrode connected with the second conductor. The first testing module can apply a preset current to the first conductor. The second testing module can be connected to the sample to be tested in an intermittent manner during the application of the preset current. The second testing module can perform a first insulation performance test on the sample to be tested when the sample to be tested is in a rapid temperature rising working condition, and perform a second insulation performance test on the sample to be tested when the first testing module stops applying the preset current and the sample to be tested meets a first temperature condition.

Description

Technical Field

[0001] This application relates to the field of electrical safety and arc behavior assessment technology of superconducting magnets, and in particular to an insulation performance testing device and method for simulating the rapid heating process of a superconducting magnet without quench relief. Background Technology

[0002] During unrelieved quenching, the inter-turn insulation layer of a superconducting magnet experiences severe thermal shock and high electric field coupling due to the rapid, short-term heating of the local conductor. This significantly degrades its insulation resistance and breakdown voltage characteristics, potentially leading to insulation failure and inducing inter-turn short circuits or arcing. This real-time evolution and degradation of electrical properties directly determines the insulation failure threshold and arc initiation conditions under quenching faults, thus affecting the safe and stable operation of large superconducting magnet systems such as fusion devices. However, current technologies struggle to simulate the real-world conditions of rapid conductor heating during unrelieved quenching and cannot obtain online data on the resistance evolution characteristics and breakdown voltage characteristics of the insulation material during rapid heating. Consequently, the degradation mechanism and failure boundary of insulation electrical properties under quenching thermal shock remain unclear, resulting in a lack of basis for assessing the risk of arcing faults in superconducting magnets. Summary of the Invention

[0003] This application provides an insulation performance testing device and method for simulating the rapid heating process of a superconducting magnet without relief of quench loss.

[0004] This application provides an insulation performance testing device for simulating the rapid heating process of a superconducting magnet without relief of quench loss. The insulation performance testing device includes a sample to be tested, a first testing module, and a second testing module, wherein the first testing module and the second testing module are electrically isolated. The test sample includes a first conductor and a second conductor that are mutually insulated and isolated from each other, and an inter-conductor insulating layer disposed between the first conductor and the second conductor. The cross-sectional dimensions of the first conductor and the second conductor are both matched with the cross-sectional dimensions of the conductor used in the superconducting magnet. The first insulating structure of the inter-conductor insulating layer is consistent with the inter-turn insulating layer structure of the superconducting magnet. The first test module includes a first electrode and a second electrode, wherein the first electrode is connected to a first end of the first conductor and the second electrode is connected to a second end of the first conductor; The second test module includes a first electrode shared with the first test module, and a third electrode connected to the second conductor; The first test module is configured to apply a preset current to the first conductor to heat up the first conductor, thereby simulating the rapid heating condition of the superconducting magnet during the unrelieved quench process. The preset current is continuously applied and remains uninterrupted during the test. The second test module is configured to intermittently connect to the sample under test during the application of the preset current, so as to realize intermittent periodic insulation performance testing; The second test module selectively connects or disconnects from the sample under test via an isolation switching unit, so that the measurement circuit does not affect the application of the preset current of the first test module when it is connected. The second test module is configured to perform a first insulation performance test on the sample under test when the sample under test is under the rapid heating condition, and to perform a second insulation performance test on the sample under test when the first test module terminates the application of the preset current and the sample under test meets the first temperature condition, wherein the first temperature condition is used to characterize that the temperature of the first conductor is greater than or equal to the preset temperature.

[0005] Thus, by constructing experimental prototypes that match the actual structure of superconducting magnets, the reliability of experimental results can be ensured, thereby guaranteeing the authenticity of the conductivity behavior assessment. Furthermore, the intermittent periodic testing of insulation resistance during heating and the breakdown voltage testing at high temperatures can be performed simultaneously on the same device. This allows for the acquisition of the dynamic electrical performance evolution characteristics of the insulating material during rapid heating, as well as the testing of the true withstand voltage limit of the insulation at high temperatures, providing a basis for the risk assessment of arc faults in superconducting magnets.

[0006] In some embodiments, the test sample further includes a ground insulation layer that covers the outer surfaces of the first conductor and the second conductor.

[0007] In this way, the insulation structure of the superconducting magnet conductor can be restored, taking into account the real service environment of inter-turn insulation and insulation to ground. This can eliminate the interference of conductor leakage current on the test results during the test, thereby improving the accuracy of insulation performance test data.

[0008] In some embodiments, the first test module further includes a heating power supply, a current monitoring unit, and an overcurrent protection unit. The heating power supply is electrically connected to the first electrode and the second electrode, respectively. The current monitoring unit is connected to the power supply circuit of the first test module, and the overcurrent protection unit is electrically connected to the heating power supply. The heating power supply is configured to output the preset current to the first conductor so that the first conductor heats up to the target temperature within a preset time. The preset time and the target temperature are both matched with the rapid heating condition of the superconducting magnet during the unrelieved quench process. The current monitoring unit is configured to monitor the current data in the power supply circuit of the first test module; The overcurrent protection unit is configured to trigger a protection action when the current data monitored by the current monitoring unit is greater than or equal to a preset current threshold, thereby limiting or cutting off the output of the heating power supply to suppress the overcurrent state and ensure the normal execution of the intermittent insulation test process of the second test module.

[0009] Thus, the heating power supply enables controllable output of a preset current, the current monitoring unit enables real-time continuous monitoring of the heating circuit current, and the overcurrent protection unit enables rapid response and safety protection under abnormal operating conditions. Simultaneously, when the overcurrent protection unit is triggered, it limits the output of the heating power supply to ensure the normal execution of the intermittent insulation test process of the second test module. This ensures both high-fidelity simulation of the unrelieved overcurrent heating condition and safe protection during the test process while simultaneously facilitating the acquisition of test data.

[0010] In some embodiments, the insulation performance testing device further includes a first acquisition module, which is electrically connected to the first testing module based on an isolated sampling method; The first acquisition module is configured to acquire and store current data in the power supply circuit of the first test module, output voltage data of the heating power supply, and temperature data of the first conductor.

[0011] In this way, operating parameters of the entire heating process can be collected simultaneously, enabling traceability of key parameters in the heating process. Furthermore, the design of the loop isolation unit can solve the problem of strong electromagnetic interference from the high-current heating loop contaminating the collected signal, thereby improving the accuracy and signal-to-noise ratio of the collected data. At the same time, it can effectively avoid electrical impacts from the high-voltage loop on the acquisition equipment, ensuring the safe operation of the acquisition system.

[0012] In some embodiments, the second test module further includes a test power supply unit, which is electrically connected to the first electrode and the third electrode respectively, and the test power supply unit includes a first test power supply and a second test power supply. The second test module is configured to intermittently connect to the sample under test through the first test power supply during the rapid heating condition and the first test module continuously applies the preset current to the first conductor, so as to apply the first test voltage to perform the first insulation performance test. Wherein, the amplitude of the first test voltage is lower than the preset safe test voltage threshold of the insulation layer between the conductors, so as to avoid causing a breakdown. After the first test module terminates the application of the preset current and the sample under test meets the first temperature condition, the second test module switches to the second test power supply and applies a second test voltage with gradually increasing amplitude to the sample under test to perform the second insulation performance test. The voltage amplitude of the second test voltage is greater than the voltage amplitude of the first test voltage.

[0013] In this way, the low-voltage first test power supply can perform non-destructive periodic insulation resistance testing during the heating process, which not only avoids premature insulation breakdown and ensures continuous stability under temperature rise conditions, but also avoids electrical interference to the heating circuit and ensures the accuracy of test data. Furthermore, the high-voltage, gradually increasing second test power supply can capture the critical value of insulation breakdown voltage under high temperature conditions, restoring the true withstand voltage limit of the insulation.

[0014] In some embodiments, the insulation performance testing device further includes a second acquisition module, which is electrically connected to the second testing module; The second acquisition module is configured to acquire and store the insulation resistance data of the inter-conductor insulation layer during the first insulation performance test; And the second test module tests the voltage and current data in the circuit during the second insulation performance test; And during the second insulation performance test, the breakdown voltage data corresponding to the gradual increase of the output voltage of the second test power supply until the insulation layer between the conductors breaks down.

[0015] In this way, insulation performance data from two testing phases can be collected, the dynamic evolution of insulation resistance during the entire heating process can be recorded in real time, and the critical voltage value of insulation breakdown can be captured. Furthermore, the second acquisition module can form a one-to-one mapping relationship with the operating condition data of the first acquisition module, constructing a multi-dimensional correlation model of insulation resistance-temperature-time-breakdown voltage, providing data support for subsequent analysis and optimization.

[0016] In some embodiments, the insulation performance testing device further includes a control module, which is electrically connected to the first acquisition module, the first test module, the second acquisition module, and the second test module, respectively. The control module is configured to: When the heating time of the first conductor reaches the preset heating time, or when the real-time temperature of the first conductor reaches the target temperature, the first test module is controlled to terminate the application of the preset current; and when the insulation resistance parameter of the insulation layer between the conductors drops to the preset resistance range, an early warning signal is generated. When there is an abnormality in the current data in the power supply circuit of the first test module or the temperature data of the first conductor, the first test module is controlled to terminate the application of the preset current.

[0017] In this way, the heating process can be controlled according to the preset quench condition to ensure the repeatability and consistency of multiple parallel tests. It can also terminate the heating in time according to the real-time deterioration of the insulation resistance, capture the key node of the sudden change in insulation performance, and avoid test failure caused by overheating of the sample.

[0018] In some embodiments, the second test module further includes a current limiting protection unit connected in series in the power supply circuit of the second test module; The current limiting protection unit is configured to limit the output current of the second test power supply when a breakdown of the insulation layer between the conductors is detected during the second insulation performance test, so as to suppress the continuous overcurrent state in the power supply circuit after the breakdown and protect the test power supply unit and the sample under test.

[0019] In this way, the output current of the second test power supply can be quickly limited at the moment the insulation layer breaks down, suppressing the continuous overcurrent state after the breakdown and avoiding damage to precision equipment such as the test power supply and data acquisition module by large current surges, thereby reducing the wear and maintenance costs of the test equipment. At the same time, it can prevent the sample under test from being burned out by the large current after the breakdown, preserving the failure state of the insulation and not affecting the voltage stability and data acquisition accuracy during the boost process before the breakdown.

[0020] In some embodiments, the insulation performance testing device further includes a circuit isolation unit disposed between the second test module and the first test module, used to achieve electrical isolation between the test circuit of the second test module and the heating circuit of the first test module; the circuit isolation unit is connected to the heating circuit of the first test module. The circuit isolation unit is configured to disconnect the electrical connection between the heating circuit of the second test module and the first test module, so as to achieve electrical isolation between the first test module and the second test module.

[0021] In this way, the circuit isolation unit is directly connected to the heating circuit of the first test module, which can cut off the electrical connection path between the second test module and the heating power supply, and realize reliable electrical isolation between the heating circuit and the test circuit from the hardware level.

[0022] This application also provides an insulation performance testing method, which is implemented based on the above-described insulation performance testing device, and the method includes: Based on the first test module, a preset current is applied to the first conductor to raise the temperature of the first conductor, thereby simulating the rapid heating condition of the superconducting magnet during the unrelieved quench process; During the continuous application of the preset current, the sample under test is intermittently connected through the second test module to perform a first insulation performance test on the sample under test. When the first test module terminates the application of the preset current and the sample under test meets the first temperature condition, the second test module performs a second insulation performance test on the sample under test, wherein the second insulation performance test includes gradually increasing the test voltage until breakdown occurs.

[0023] Thus, by applying a preset current through the first test module, the rapid heating condition of a superconducting magnet without quench relief is simulated. Then, during the continuous heating process, the sample is intermittently connected through the second test module to complete the periodic insulation performance test. Finally, when heating is terminated and the sample is still at a high temperature, the breakdown voltage test is completed through the second test module. In this way, the simulation of the extreme condition of the superconducting magnet without quench relief and the entire process of insulation performance testing can be seamlessly integrated, and the dynamic electrical performance evolution characteristics of the insulating material during rapid heating, as well as the true withstand voltage limit at high temperatures, can be obtained.

[0024] In some embodiments, applying a preset current to the first conductor based on the first test module to raise the temperature of the first conductor, thereby simulating the rapid temperature rise of the superconducting magnet during the unmitigated quench process, includes: Based on the first test module, a preset current is applied to the first conductor to raise the temperature of the first conductor to the target temperature within a preset time. The preset time and the target temperature are both matched with the rapid heating condition of the superconducting magnet during the unrelieved quench process.

[0025] In this way, the temperature rise rate, heating time and target temperature during the unrelieved quench process of the superconducting magnet can be reproduced, ensuring that the test conditions match the real fault scenario, and making the insulation performance test results have strong engineering applicability and reference value.

[0026] In some embodiments, the method further includes: Based on the first acquisition module, the current data in the power supply circuit of the first test module, the output voltage data of the heating power supply, and the temperature data of the first conductor are acquired and stored.

[0027] In this way, operating parameters throughout the entire heating process can be recorded, enabling traceability of key parameters during the test. Furthermore, it allows for the establishment of a correlation between temperature rise curves, current changes, and insulation performance evolution, providing fundamental data for analyzing insulation degradation patterns. In addition, it enables real-time monitoring of abnormal operating conditions during the heating process, providing real-time data support for the heating termination protection logic and ensuring the controllability and stability of the test process.

[0028] In some embodiments, the test sample is intermittently connected via the second test module to perform a first insulation performance test on the test sample, including: Based on the second test module, during the continuous application of the preset current, the test sample is intermittently connected to the test sample through the first test power supply, and a first test voltage is applied to the test sample to perform the first insulation performance test. The amplitude of the first test voltage is lower than the preset safety test threshold of the inter-conductor insulation layer to avoid breakdown of the inter-conductor insulation layer.

[0029] In this way, by using a low-voltage, non-destructive testing method, non-destructive periodic testing of insulation resistance is achieved during continuous heating. This not only avoids premature insulation breakdown and ensures continuous and stable heating process, but also obtains the dynamic evolution characteristics of insulation resistance with temperature and time. Furthermore, it effectively avoids electrical interference from the test voltage to the heating circuit, ensuring the realism of the operating condition simulation and the accuracy of the test data.

[0030] In some implementations, when the first test module terminates the application of the preset current and the sample under test meets the first temperature condition, a second insulation performance test is performed on the sample under test, including: Based on the second test module, under the action of the second test power supply, a second test voltage with gradually increasing amplitude is applied to the sample under test to perform a withstand voltage test on the insulation layer between the conductors until breakdown occurs; The second test voltage gradually exceeds the first test voltage during the voltage boosting process.

[0031] Thus, by completing the breakdown voltage test while the insulation is still at a high temperature after heating is stopped, the insulation condition deviation caused by cooling and reheating can be avoided, thereby enabling the breakdown voltage obtained from the test to reflect the true withstand voltage limit of the insulation under quench conditions.

[0032] This application also provides a computer device in which a computer program is stored in a memory, and when the processor executes the computer program, it implements the steps of the above method.

[0033] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the above-described method.

[0034] Additional aspects and advantages of embodiments of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of embodiments of this application. Attached Figure Description

[0035] The above and additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is one of the structural schematic diagrams of an insulation performance testing device according to certain embodiments of this application; Figure 2 This is a second schematic diagram of the insulation performance testing device according to certain embodiments of this application; Figure 3 This is the third schematic diagram of the insulation performance testing device according to certain embodiments of this application; Figure 4 This is the fourth schematic diagram of the insulation performance testing device according to certain embodiments of this application; Figure 5 This is the fifth of the structural schematic diagrams of the insulation performance testing device according to certain embodiments of this application; Figure 6 This is a schematic diagram of the insulation performance testing device according to certain embodiments of this application; Figure 7 This is one of the flowcharts illustrating the insulation performance testing method of certain embodiments of this application; Figure 8 This is a second schematic flowchart of an insulation performance testing method according to certain embodiments of this application; Figure 9 This is the third flowchart illustrating the insulation performance testing method of certain embodiments of this application; Figure 10 This is the fourth flowchart illustrating the insulation performance testing method of certain embodiments of this application; Figure 11 This is the fifth flowchart illustrating the insulation performance testing method of certain embodiments of this application; Figure 12 This is a schematic flowchart of the insulation performance testing method of some embodiments of this application; Figure 13 This is the seventh flowchart illustrating the insulation performance testing method of certain embodiments of this application. Detailed Implementation

[0036] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the embodiments of this application, and should not be construed as limiting the embodiments of this application.

[0037] During long-term operation or sudden quenching of a superconducting magnet, the inter-turn insulation layer may experience a short-circuit arc due to local defects, voltage surges, or other factors. Under the heat of the arc, the conductivity of the inter-turn insulation layer degrades from an insulating state to a conductive state. Specifically, quenching refers to the sudden loss of superconductivity in a superconducting magnet due to factors such as abnormal local temperature increases or current overload, instantly transitioning from a zero-resistance state to a resistive state. This process is accompanied by a violent energy release and a rapid temperature rise. Unmitigated quenching specifically refers to the extreme condition where, after a quenching fault occurs, the magnet quenching protection system fails to promptly and effectively discharge the magnet's stored energy, or the protection system itself malfunctions, leading to a rapid temperature rise of the local current-carrying conductor from a low temperature to a high temperature under continuous high current.

[0038] During the aforementioned process, the inter-turn insulation layer, which covers the conductors and plays a core role in electrical isolation, will be subjected to severe thermal stress, thermal aging, and thermal decomposition caused by rapid temperature rise, resulting in structural damage to the insulation material. At the same time, the high-intensity electric field formed by the uneven distribution of current carrying capacity and electric field in the conductors will cause a rapid and irreversible deterioration in the electrical performance of the inter-turn insulation, ultimately leading to significant insulation failure.

[0039] Once the insulation fails significantly, it will quickly induce an inter-turn short circuit fault. The short circuit current will further aggravate local heating and electric field distortion, which will then trigger an electric arc discharge. The high-temperature ablation and energy impact of the electric arc will directly cause the superconducting magnet conductor to melt, the insulation structure to burn out, and the magnet to be permanently damaged as a whole. It may even cause major safety accidents such as cryogenic container leakage and device shutdown, directly threatening the long-term safety, stability and continuous operation of large superconducting magnet systems such as fusion devices.

[0040] Therefore, it is necessary to analyze and study the real-time evolution law of insulation resistance of inter-turn insulation under unmitigated quench thermal shock and the breakdown voltage characteristics under high temperature hot state in order to determine the insulation failure threshold, clarify the conditions for arc initiation and development, and analyze the quench fault evolution mechanism.

[0041] However, the relevant technologies cannot reproduce the real-world conditions of rapid conductor heating, strong thermal inertia, and short-term high temperatures during unresolved quenching. The heating mode, temperature rise rate, and temperature history deviate significantly from actual faults. Furthermore, it is impossible to conduct non-interference, continuous periodic testing of insulation resistance during the dynamic process of rapid conductor heating to capture the real-time evolution of insulation performance. It also cannot quickly complete breakdown voltage testing within the critical window period after heating has stopped, while the insulation is still in a high-temperature hot state, to obtain true withstand voltage data at high temperatures.

[0042] Based on the above issues, please refer to Figure 1 and Figure 2 This application provides an insulation performance testing device 1000 that simulates the rapid heating process of a superconducting magnet without quench relief. The insulation performance testing device 1000 includes a sample to be tested 100, a first testing module 200 and a second testing module 300, and the first testing module 200 and the second testing module 300 are electrically isolated. The test sample 100 includes a first conductor 110 and a second conductor 120 that are mutually insulated and isolated from each other, and an inter-conductor insulation layer 130 disposed between the first conductor 110 and the second conductor 120. The cross-sectional dimensions of the first conductor 110 and the second conductor 120 are matched with the cross-sectional dimensions of the conductors used in the superconducting magnet. The first insulation structure of the inter-conductor insulation layer 130 is consistent with the structure of the inter-turn insulation layer of the superconducting magnet. The first test module 200 includes a first electrode 210 and a second electrode 220. The first electrode 210 is connected to a first end of the first conductor 110, and the second electrode 220 is connected to a second end of the first conductor 110. The second test module 300 includes a first electrode 210 shared with the first test module 200, and a third electrode 310 connected to the second conductor 120; The first test module 200 is configured to apply a preset current to the first conductor 110 to raise the temperature of the first conductor 110, thereby simulating the rapid heating condition of the superconducting magnet in the process of not alleviating quench loss. The preset current is continuously applied and remains uninterrupted during the test. The second test module 300 is configured to intermittently connect to the sample under test 100 during the application of a preset current, so as to realize intermittent periodic insulation performance testing. The second test module 300 selectively connects or disconnects from the sample under test 100 through an isolation switching unit, so that the measurement circuit does not affect the application of the preset current of the first test module 200 when it is connected. The second test module 300 is configured to perform a first insulation performance test on the sample 100 under a rapid heating condition, and to perform a second insulation performance test on the sample 100 when the first test module 200 terminates the application of the preset current and the sample 100 meets the first temperature condition, wherein the first temperature condition is used to characterize that the temperature of the first conductor 110 is greater than or equal to the preset temperature.

[0043] Specifically, a superconducting magnet refers to a high-performance magnet constructed based on the zero-resistance characteristics of superconducting materials, including superconducting coils and an interconductor insulating layer 130, etc. Among them, the superconducting coil is made of superconducting wire and is usually a multi-turn structure.

[0044] Unrelieved quench is one of the fault conditions in the operation of a superconducting magnet. Specifically, it refers to the failure of the quench protection system to release the energy stored in the magnet in a timely and effective manner after the superconducting magnet has lost quench, resulting in a short-term and rapid temperature rise in the local conductor under the action of a large current.

[0045] The rapid heating condition corresponds to the situation where, during the unresolved quench process, the conductor rapidly rises to hundreds of degrees Celsius or even higher in a short period of time, from a few seconds to a dozen seconds, under the Joule heating effect of a large current. This is different from the conventional test conditions of steady-state high temperature and slow heating.

[0046] The test sample 100 is a test specimen prepared to simulate the actual inter-turn structure of a superconducting magnet. It includes a first conductor 110 and a second conductor 120 that are mutually insulated, and an inter-conductor insulation layer 130 disposed between them. The first conductor 110 is a heating conductor, and the second conductor 120 is a test auxiliary conductor. The cross-sectional dimensions of both are matched to those of the conductors actually used in superconducting magnets, ensuring that the temperature rise rate and heat distribution during the heating process can simulate unrelieved quenching. The inter-conductor insulation layer 130 is the core test object of this device. Its insulation structure conforms to the structure of the actual inter-turn insulation layer of a superconducting magnet, including the type of insulating material, number of layers, thickness, and molding process, all consistent with engineering applications, fundamentally ensuring the representativeness of the test results to actual engineering scenarios.

[0047] The insulation performance testing device 1000 adopts an electrically isolated dual-module architecture, including a first test module 200 and a second test module 300. The two are electrically independent through isolation devices to avoid signal interference and equipment damage risks between the high-current heating circuit and the test circuit.

[0048] The first test module 200 is a heating condition simulation module, including a first electrode 210 and a second electrode 220 reliably connected to both ends of the first conductor 110. The first electrode 210 and the second electrode 220 are used to uniformly introduce the large current of the heating power supply 230 into the first conductor 110 to construct a large current heating circuit. The first test module 200 can apply a preset current to the first conductor 110. This preset current is a large current calculated based on the conductor specifications, target temperature rise rate, and target temperature, which can make the first conductor 110 heat up to the target temperature within a preset time. Moreover, the preset current is continuously applied during the test, reproducing the real fault scenario where the conductor continuously suffers Joule heating during the unresolved quench process.

[0049] The second test module 300 is an insulation performance test module, consisting of a first electrode 210 and a third electrode 310 connected to the second conductor 120. The third electrode 310, in conjunction with the first electrode 210, forms a three-electrode test structure independent of the heating circuit, structurally decoupling the heating circuit from the test circuit. The second test module 300 has two main operating logics: During the process of continuously applying a preset current and the conductor being in a rapid heating condition, the test sample 100 is intermittently connected through an isolation switching unit to achieve periodic insulation performance testing. Furthermore, the second test module 300 can perform two types of insulation performance tests under two different operating conditions. The first insulation performance test is a periodic insulation resistance test performed under rapid heating conditions to obtain the real-time evolution of insulation resistance with temperature and heating time. The second insulation performance test is a breakdown voltage test performed when the first test module 200 terminates the application of the preset current and the test sample 100 meets the first temperature condition. The first temperature condition refers to the temperature of the first conductor 110 being greater than or equal to the preset temperature, that is, the sample is still in a high temperature state and has not yet cooled to room temperature. This ensures that the working conditions of the breakdown test are approximately consistent with the thermal state of the insulation after the actual quench, and obtains the true withstand voltage limit of the insulation layer after thermal shock.

[0050] It should be noted that when the second test module 300 is selectively connected or disconnected from the sample under test 100 through the isolation switching unit, it does not mean that there is no slight electrical disturbance applied to the preset current of the first test module 200. Rather, the influence is controlled within a negligible range below the current control accuracy of the heating power supply and the allowable error of the test. Thus, it can be approximately assumed that the measurement circuit does not affect the application of the preset current of the first test module 200 when it is connected.

[0051] The isolation switching unit is a fast switching device with high isolation withstand voltage capability, typically employing high-voltage isolation relays, solid-state switches, and other devices with high isolation withstand voltage capability. The isolation switching unit enables selective switching between the test circuit and the sample under test 100, ensuring that the impact of continuous high current applied to the first test module 200 when the test circuit is connected is negligible. This allows for both periodic real-time testing of insulation performance and guarantees the stability of the heating conditions.

[0052] The first temperature condition is used to characterize that the temperature of the first conductor 110 is greater than or equal to a preset temperature. This preset temperature is a target temperature set based on the limit temperature rise of a real unresolved quench fault in a superconducting magnet, ensuring that the insulation layer is in a high-temperature state similar to the real fault during testing, avoiding state deviations caused by testing after cooling. In some embodiments, the first temperature condition also includes that the temperature change rate of the first conductor 110 is lower than a preset temperature rise threshold. It should be noted that this temperature change rate refers to the cooling rate of the first conductor 110 after heating is terminated, and the setting of the preset temperature rise threshold must match the thermophysical characteristics of the sample under test and the test accuracy requirements. By limiting the temperature change rate of the first conductor 110 to be lower than the preset temperature rise threshold, the sample under test 100 can be in a relatively stable thermal state before the second insulation performance test, thereby reducing the interference of rapid temperature changes on the test results.

[0053] Please see Figure 3 In some embodiments, the insulation performance testing device 1000 can be as follows: Figure 3 As shown. Among them, the test sample 100 is the test sample module, the first heating electrode is the first electrode 210, the second heating electrode is the second electrode 220, the third test electrode is the third electrode 310, the control and acquisition system includes the control module 700, the first acquisition module 400 and the second acquisition module 600, and the heating circuit includes the heating power supply 230.

[0054] In summary, an insulation performance testing device 1000 is provided. By constructing an experimental sample that matches the actual superconducting magnet structure, the reliability of experimental results can be ensured, thereby ensuring the authenticity of the conductivity behavior assessment. Furthermore, it enables the simultaneous implementation of intermittent periodic testing of insulation resistance during heating and breakdown voltage testing at high temperatures on the same device. This allows for the acquisition of the dynamic electrical performance evolution characteristics of the insulating material during rapid heating, as well as the testing of the true withstand voltage limit of the insulation at high temperatures, providing a basis for the risk assessment of arc faults in superconducting magnets.

[0055] Please refer to the following: Figure 1 In some embodiments, the test sample 100 further includes a ground insulation layer 140, which covers the outer surfaces of the first conductor 110 and the second conductor 120.

[0056] Specifically, the ground insulation layer 140 refers to a component of the superconducting magnet insulation system, specifically a structural layer covering the outer surface of the current-carrying conductor to achieve electrical insulation between the current-carrying conductor and grounded components in the superconducting magnet system, such as cryogenic containers and magnet cores. The ground insulation layer 140 is typically made of composite materials with the same low-temperature resistance, radiation resistance, and high insulation strength as the inter-turn insulation, such as glass fiber reinforced epoxy resin composite materials and polyimide films. Its thickness, number of layers, and molding process are consistent with the actual ground insulation design of the superconducting magnet.

[0057] Furthermore, insulating filler blocks are provided at the first end of the first conductor and the second end of the second conductor. The insulating filler blocks are made of G10 material. The insulating filler block refers to an insulating component provided at the end of the conductor, used to fill the structural gap at the end of the conductor, eliminate the phenomenon of electric field concentration at the end, suppress end discharge, and ensure that the test resistance is at the position of inter-turn insulation rather than end discharge. This insulating filler block is the end insulation protection component of the experimental sample.

[0058] In this way, the insulation structure of the superconducting magnet conductor can be restored, taking into account the real service environment of inter-turn insulation and insulation to ground. This can eliminate the interference of conductor leakage current on the test results during the test, thereby improving the accuracy of insulation performance test data.

[0059] Please see Figure 4 In some embodiments, the first test module 200 further includes a heating power supply 230, a current monitoring unit 240 and an overcurrent protection unit 250. The heating power supply 230 is electrically connected to the first electrode 210 and the second electrode 220 respectively. The current monitoring unit 240 is connected to the power supply circuit of the first test module 200. The overcurrent protection unit 250 is electrically connected to the heating power supply 230. The heating power supply 230 is configured to output a preset current to the first conductor 110 so that the first conductor 110 heats up to the target temperature within a preset time. The preset time and the target temperature are both matched with the rapid heating condition of the superconducting magnet during the unrelieved quench process. The current monitoring unit 240 is configured to monitor the current data in the power supply circuit of the first test module 200; The overcurrent protection unit 250 is configured to limit or cut off the output of the heating power supply 230 when the current data monitored by the current monitoring unit 240 is greater than or equal to a preset current threshold, so as to suppress the overcurrent state and ensure the normal execution of the intermittent insulation test process of the second test module 300.

[0060] Specifically, the heating power supply 230 refers to the power supply device that provides a large current output to the first test module 200, typically a DC power supply with a large current output. The output current range of the heating power supply 230 can be adjusted over a wide range according to the cross-sectional area of ​​the first conductor 110 of the sample under test 100, the material resistivity, and the target temperature rise rate. It can maintain a stable current output within a preset heating time, ensuring that the Joule heat generation of the first conductor 110 matches the preset value, thereby raising the temperature of the first conductor 110 to the target temperature matching the unrelieved quench condition within the preset time. The two output terminals of the heating power supply 230 are electrically connected to the first electrode 210 and the second electrode 220, respectively. Together with the first conductor 110, they form a closed heating circuit, which is the core power source for simulating the rapid temperature rise condition.

[0061] The current monitoring unit 240 refers to a measuring device used to monitor the current data in the heating power supply circuit of the first test module 200. It typically employs wide-range, fast-response Hall current sensors, shunts, and other similar devices. It can be used to detect dynamic characteristics such as steady-state fluctuations and transient changes in current during the heating process. The output signal of the current monitoring unit 240 can be transmitted to the control module 700 to adjust the output of the heating power supply 230, ensuring the circuit current remains within a preset range. The output signal of the current monitoring unit 240 can also be transmitted to the overcurrent protection unit 250 as one of the trigger criteria for overcurrent protection operation.

[0062] The overcurrent protection unit 250 is a safety protection device electrically connected to the heating power supply 230, capable of quickly triggering protective action when an overcurrent abnormality occurs in the heating circuit. It typically consists of a fast-acting circuit breaker, a high-breaking-capacity fast-acting fuse, a thyristor fast-turn-off circuit, and surge suppression devices, possessing rapid response capabilities. The overcurrent protection unit 250 can quickly limit or cut off the output of the heating power supply 230 when an abnormal overcurrent occurs in the circuit, preventing equipment damage and safety accidents caused by continuous circuit overload.

[0063] The preset current threshold refers to the current protection critical value set in advance based on the rated output capacity of the heating power supply 230, the maximum carrying current of the test sample 100, and the safety boundary of the target temperature rise condition. When the loop current data collected by the current monitoring unit 240 is greater than or equal to the preset current threshold, it is determined that an overcurrent abnormality has occurred in the loop, and the overcurrent protection unit 250 immediately triggers the protection action.

[0064] Thus, the heating power supply 230 enables controllable output of the preset current, the current monitoring unit 240 enables real-time continuous monitoring of the heating circuit current, and the overcurrent protection unit 250 enables rapid response and safety protection under abnormal operating conditions. Simultaneously, when the overcurrent protection is triggered, the overcurrent protection unit limits the output of the heating power supply to ensure the normal execution of the intermittent insulation test process of the second test module. This ensures both high-fidelity simulation of the unrelieved overcurrent heating condition and safe protection during the test process while simultaneously facilitating the acquisition of test data.

[0065] Please see Figure 5 In some embodiments, the insulation performance testing device 1000 further includes a first acquisition module 400, which is electrically connected to the first test module 200 based on an isolated sampling method. The first acquisition module 400 is configured to acquire and store current data in the power supply circuit of the first test module 200, output voltage data of the heating power supply 230, and temperature data of the first conductor 110.

[0066] Specifically, the first acquisition module 400 refers to a hardware and software suite used to acquire, condition, convert, and store key parameters throughout the entire testing process. It typically includes multi-channel signal conditioning circuits, a synchronous data acquisition card, a data storage unit, and a timing control unit, featuring multi-channel synchronous acquisition, high sampling rate, wide measurement range, and high resolution. Furthermore, the first acquisition module 400 can simultaneously acquire and store the heating circuit current, voltage, and conductor temperature in real time, serving as a bridge connecting the testing device hardware with subsequent data analysis.

[0067] In this way, the first acquisition module 400 is electrically connected to the first test module 200, and can directly acquire the current data in the heating circuit of the first test module 200 and the output voltage data of the heating power supply 230. At the same time, it can acquire the temperature data of the first conductor 110 output by the temperature sensor set on the first conductor 110, and can realize the acquisition of all key parameters of the test process.

[0068] In this way, operating parameters of the entire heating process can be collected simultaneously, enabling traceability of key parameters in the heating process. Furthermore, the design of the loop isolation unit 500 can solve the problem of strong electromagnetic interference from the high-current heating circuit contaminating the collected signal, thereby improving the accuracy and signal-to-noise ratio of the collected data. At the same time, it can effectively avoid electrical impacts from the high-voltage circuit on the acquisition equipment, ensuring the safe operation of the acquisition system.

[0069] Please see Figure 6In some embodiments, the second test module 300 further includes a test power supply unit 320, which is electrically connected to the first electrode 210 and the third electrode 310 respectively, and includes a first test power supply and a second test power supply. The second test module 300 is configured to intermittently connect to the test sample 100 through the first test power supply during the process of the test sample 100 being in a rapid heating condition and the first test module 200 continuously applying a preset current to the first conductor 110, so as to apply the first test voltage to perform the first insulation performance test. The amplitude of the first test voltage is lower than the preset safe test voltage threshold of the inter-conductor insulation layer 130 to avoid causing a breakdown. After the first test module 200 terminates the application of the preset current and the test sample 100 meets the first temperature condition, the second test module 300 switches to the second test power supply and applies a second test voltage with gradually increasing amplitude to the test sample 100 to perform the second insulation performance test. The voltage amplitude of the second test voltage is greater than that of the first test voltage.

[0070] Specifically, the test power supply unit 320 refers to the power supply and signal generation device of the second test module 300, providing a controllable test voltage for insulation performance testing. The output terminals of the test power supply unit 320 are electrically connected to the first electrode 210 and the third electrode 310 respectively, forming an independent closed test circuit together with the conductor insulation layer 130 of the sample under test 100, and are electrically isolated from the heating circuit of the first test module 200. It should be noted that the test power supply unit 320 adopts a dual-power independent design, including a first test power supply and a second test power supply. The two power supplies are interlocked and switched through a fast-switching relay, ensuring that only one power supply is connected to the test circuit at any given time, avoiding crosstalk and damage between high and low voltage power supplies.

[0071] The first test power supply refers to a low-voltage precision test power supply specifically designed for first insulation performance testing. It is usually a DC regulated power supply or a megohmmeter built-in test power supply. Its output voltage amplitude is stable and the ripple coefficient is low. It can provide test voltages far below the 130 breakdown threshold of the insulation layer between conductors. It has microampere-level small current measurement capability and can calculate the high-resistivity resistance value of the insulation layer. It is the hardware for realizing the periodic testing of insulation resistance during heating.

[0072] The second test power supply refers to an adjustable DC high-voltage power supply specifically designed for the second insulation performance test. Its output voltage can be continuously and linearly adjusted within the range of zero to several thousand volts or even higher. It has the functions of constant voltage boost and fast overcurrent cutoff. It can gradually increase the output voltage according to the preset boost rate until the insulation layer 130 between the conductors breaks down. At the same time, it has high voltage current limiting capability to avoid irreversible damage to the power supply and the sample caused by the large current after breakdown. It is the core hardware for obtaining the high temperature breakdown voltage of the insulation layer.

[0073] The first insulation performance test refers to the periodic test of inter-turn insulation resistance during the heating process. It can acquire the resistance evolution characteristics of the insulation layer 130 between conductors in real time during rapid heating, and clarify the correspondence between insulation degradation and temperature and heating time. The implementation window of this first insulation performance test is the entire process in which the first test module 200 continuously applies a preset current and the first conductor 110 is under rapid heating. The test method is that the first test power supply is intermittently connected to the test circuit through an isolation switching unit to avoid interference to the heating circuit caused by long-term connection, while ensuring the time resolution of the test data.

[0074] The preset safety test voltage threshold refers to the highest critical value of the test voltage set in advance based on the material characteristics, thickness, and structure of the insulation layer 130 between conductors, as well as the rated electric field strength during actual operation of the superconducting magnet. This preset safety test voltage threshold is much lower than the minimum breakdown voltage of the insulation layer at room temperature and the expected highest test temperature, ensuring that the insulation layer will not break down due to excessively high test voltage throughout the first insulation performance test, guaranteeing that the structure and performance of the insulation layer are not affected by the test itself, and ensuring the authenticity of the heating conditions and insulation degradation process.

[0075] The second insulation performance test refers to the inter-turn insulation breakdown voltage test under high temperature conditions. This test can obtain the true thermal withstand voltage limit of the insulation layer after rapid temperature rise thermal shock, clarifying the influence of the insulation degradation process on the breakdown voltage. The implementation window for this second insulation performance test is the moment when the first test module 200 terminates the application of the preset current and the sample under test 100 meets the first temperature condition. That is, the time window during which the sample is still at a high temperature and has not yet experienced significant cooling, ensuring that the test conditions are approximately consistent with the true thermal state of the insulation after quench relief. When the insulation resistance of the inter-turn insulation layer has decreased to the conduction failure range or stable shunt characteristics have appeared, the breakdown voltage test is no longer performed to avoid invalid testing and equipment damage.

[0076] The second test voltage refers to the high-voltage DC voltage output by the second test power supply, used for breakdown voltage testing. The amplitude of the second test voltage gradually increases during the test according to a preset boost rate, and is greater than the amplitude of the first test voltage throughout the test, until the insulation layer breaks down. The voltage value at this point is the breakdown voltage of the insulation layer.

[0077] In this way, the low-voltage first test power supply can perform non-destructive periodic insulation resistance testing during the heating process, which not only avoids premature insulation breakdown and ensures continuous stability under temperature rise conditions, but also avoids electrical interference to the heating circuit and ensures the accuracy of test data. Furthermore, the high-voltage, gradually increasing second test power supply can capture the critical value of insulation breakdown voltage under high temperature conditions, restoring the true withstand voltage limit of the insulation.

[0078] Please refer to the following: Figure 5 In some embodiments, the insulation performance testing device 1000 further includes a second acquisition module 600, which is electrically connected to the second testing module 300. The second acquisition module 600 is configured to acquire and store the insulation resistance data of the inter-conductor insulation layer 130 during the first insulation performance test. And the second test module 300 tests the voltage and current data in the circuit during the second insulation performance test; And during the second insulation performance test, the breakdown voltage data corresponding to the gradual increase of the output voltage of the second test power supply until the insulation layer 130 between the conductors breaks down.

[0079] Specifically, the second acquisition module 600 refers to a hardware and software suite dedicated to the acquisition, conditioning, conversion, and storage of insulation performance test data from the second test module 300. It typically includes a multi-channel isolated signal conditioning circuit, a high-resolution synchronous data acquisition card, a high-speed data buffer unit, a timing synchronization unit, and a data storage unit, possessing characteristics such as high sampling rate, high input impedance, wide dynamic range, and strong anti-interference capability. The second acquisition module 600 can capture weak signal changes and transient breakdown characteristics during the insulation test process and is the core hardware for realizing insulation performance test data acquisition. It should be noted that the second acquisition module 600 and the first acquisition module 400 are electrically independent, respectively corresponding to the acquisition needs of the test circuit and the heating circuit, thus avoiding signal crosstalk between the high-voltage heating circuit and the high-voltage test circuit.

[0080] Insulation resistance data refers to the resistance value of the insulation layer 130 between conductors, calculated according to Ohm's law based on the test voltage applied by the first test power supply and the leakage current collected in the test circuit during the first insulation performance test. This insulation resistance data reflects the insulation performance state of the insulation layer at a corresponding temperature and heating time, and is a core parameter characterizing the degree of insulation degradation. In some embodiments, the insulation resistance data collected by the second acquisition module 600 includes the resistance value, test voltage value, test current value, and corresponding acquisition timestamp for each intermittent test during the full heating process from the start to the end of heating, which can be used to plot the evolution curve of insulation resistance with temperature and heating time.

[0081] The breakdown voltage data refers to the voltage value output by the second test power supply when the insulation layer 130 between conductors breaks down during the second insulation performance test. This breakdown voltage data is a core parameter characterizing the withstand voltage limit of the insulation layer after thermal shock. It should be noted that the determination of insulation breakdown is based on a sudden increase in current in the test circuit and an instantaneous drop in insulation resistance to a low-resistance conduction state. The second acquisition module 600 can capture the voltage peak at the moment of breakdown, i.e., the breakdown voltage of the insulation layer, through high-speed synchronous acquisition. At the same time, it records the voltage value and leakage current value corresponding to each step of the voltage boost process, providing full-cycle data for the analysis of the insulation breakdown process.

[0082] For the first insulation performance test, the second acquisition module 600 is triggered synchronously with the first test power supply. At the instant when the first test power supply is intermittently connected to the test circuit, the voltage and current data of the test circuit are acquired synchronously, the insulation resistance value is calculated and stored in real time, and a timestamp is added to each set of data. The temperature and heating current data acquired synchronously with the first acquisition module 400 are aligned in time sequence to ensure that each insulation resistance value can correspond to the corresponding temperature and heating process, providing a time sequence reference for constructing a multi-parameter mapping relationship of "insulation resistance-temperature-time".

[0083] For the second insulation performance test, the second acquisition module 600 is synchronized with the boost process of the second test power supply. It continuously acquires the voltage and current data of the test circuit at a sampling frequency higher than the boost rate, and monitors the current change trend in real time. When a sudden change in current is detected and the insulation resistance drops instantaneously, the current voltage value is immediately latched as the breakdown voltage. At the same time, the voltage and current curves of the entire boost process are stored. This not only allows the breakdown voltage threshold to be obtained, but also provides full-cycle data for the analysis of the insulation breakdown mechanism.

[0084] In this way, insulation performance data from two testing phases can be collected, the dynamic evolution of insulation resistance can be recorded in real time throughout the entire heating process, and the critical voltage value of insulation breakdown can be captured. Furthermore, the second acquisition module 600 can form a one-to-one mapping relationship with the operating condition data of the first acquisition module 400, constructing a multi-dimensional correlation model of insulation resistance-temperature-time-breakdown voltage, providing data support for subsequent analysis and optimization.

[0085] Please refer to the following: Figure 5 In some embodiments, the insulation performance testing device 1000 further includes a control module 700, which is electrically connected to the first acquisition module 400, the first test module 200, the second acquisition module 600, and the second test module 300, respectively. The control module 700 is configured to: When the heating time of the first conductor 110 reaches the preset heating time, or when the real-time temperature of the first conductor 110 reaches the target temperature, the first test module 200 is controlled to terminate the application of the preset current; and when the insulation resistance parameter of the insulation layer 130 between conductors drops to the preset resistance range, an early warning signal is generated; when there is an abnormality in the current data in the power supply circuit of the first test module 200 or the temperature data of the first conductor 110, the first test module 200 is controlled to terminate the application of the preset current.

[0086] Specifically, the control module 700 refers to the control and decision-making unit of the entire testing device. It is usually a programmable logic controller, industrial control computer or embedded control system. It has built-in timing control logic, threshold judgment logic, safety protection logic and human-machine interface. It can receive real-time data from each acquisition module, complete logical judgment according to the preset program, and output control commands to each execution unit to realize the full-process automated closed-loop control of the testing process.

[0087] The preset heating time refers to the duration of high-current heating that is pre-set based on the actual fault process of the superconducting magnet before the quench is relieved. It is usually several seconds to tens of seconds. In the experiment, it can be further adjusted according to the experimental safety requirements so that it can reflect the rapid heating time of the conductor during the actual quench process. It is one of the thresholds for the control module 700 to determine the termination of heating.

[0088] The target temperature refers to the temperature threshold for terminating the heating of the first conductor 110, which is preset based on the highest temperature rise of the conductor during the quenching process of the superconducting magnet. It is one of the thresholds for the control module 700 to determine the heating termination. Different target temperatures can be set according to different test requirements to obtain electrical performance data of the insulation layer under different thermal shock levels.

[0089] The preset resistance range refers to a resistance range predetermined based on the degradation characteristics of insulating materials under different temperature and electric field conditions, as well as the insulation failure criteria during the operation of superconducting magnets. This resistance range characterizes the transition range during the transition of the insulation layer between conductors from a high-resistance insulation state to a low-resistance conduction state. When the insulation resistance drops to this preset resistance range, it indicates that the insulation layer has undergone significant degradation and is approaching a failure breakdown state. This state serves as the basis for the control module 700 to generate a warning signal.

[0090] The warning signal refers to the audible and visual warning, interface prompt, or remote alarm signal generated by the control module 700 when it detects that the insulation resistance has dropped to the preset resistance range. It is used to remind the test personnel that the insulation layer has entered a critical state of deterioration. At the same time, it can trigger preset protection actions, such as stopping heating or switching test modes, to avoid insulation layer breakdown and damage.

[0091] It should be noted that the control module 700 forms a multi-parameter feedback control relationship with each functional module. Its input terminals are electrically connected to the first acquisition module 400 and the second acquisition module 600, respectively, to receive current data, voltage data, temperature data of the first conductor 110, insulation resistance data, and voltage and current data of the test circuit. Its output terminals are electrically connected to the heating power supply 230 and overcurrent protection unit 250 of the first test module 200, and the test power supply unit 320 and isolation switching unit of the second test module 300, respectively, to output corresponding control commands to realize heating process control, test mode switching, and protection action execution.

[0092] Based on the heating time and real-time temperature information of the first conductor 110 provided by the first acquisition module 400, the control module 700 outputs a termination command to the heating power supply 230 when the heating time reaches the preset heating time or the real-time temperature reaches the target temperature, so as to stop the preset current output and thus complete the controlled termination of the heating process.

[0093] Furthermore, the control module 700 makes a phased judgment on the insulation status based on the insulation resistance data acquired by the second acquisition module 600. When the insulation resistance drops to a preset resistance range, an early warning signal is generated to indicate that the insulation performance has entered a deterioration transition stage. The control module 700 can also select whether to terminate heating or switch to the breakdown test mode according to the preset control strategy to obtain the breakdown voltage data under the corresponding state.

[0094] In addition, when the current or temperature data fed back by the first acquisition module 400 shows abnormal changes, such as exceeding the preset threshold or showing an abnormal fluctuation trend, the control module 700 outputs a termination command to the heating power supply 230 and triggers the overcurrent protection unit 250 to cut off the heating circuit, thereby realizing the protection and control of abnormal operating conditions.

[0095] Through the above control logic, the heating process can be stably executed under preset operating conditions. At the same time, it can achieve phased control by combining the trend of insulation resistance change, thereby effectively capturing the critical state of insulation degradation while ensuring test repeatability.

[0096] Please refer to the following: Figure 6 In some embodiments, the second test module 300 further includes a current limiting protection unit 330, which is connected in series in the power supply circuit of the second test module 300; The current limiting protection unit 330 is configured to limit the output of the second test power supply or quickly shut it off when a breakdown of the insulation layer 130 between conductors is detected during the second insulation performance test, so as to suppress the transient large current surge in the test circuit after the breakdown and reduce the continuous overcurrent state of the power supply circuit, thereby protecting the safe operation of the second test power supply unit 320 and the sample under test 100.

[0097] Specifically, the current limiting protection unit 330 refers to a combination of fast current limiting hardware and overcurrent protection hardware specifically designed for high-voltage breakdown testing scenarios in the second test module 300. The fast current limiting hardware and overcurrent protection hardware are typically installed in series in the high-voltage power supply circuit of the second test module 300. They are usually composed of high-power high-voltage current limiting resistors, microsecond-level fast-acting fuses, transient voltage suppression diodes, high-speed thyristor turn-off circuits, and other components, possessing characteristics such as fast response capability, high withstand voltage rating, and low leakage current, enabling instantaneous current limiting protection during breakdown.

[0098] It should be noted that the current limiting protection unit 330 is connected in series on the high voltage output side or low voltage circuit side of the second test module 300, and forms a selective access structure with the second test power supply through an interlocking switching relay, so that the high voltage breakdown test circuit is only connected during the second insulation performance test.

[0099] The power supply circuit of the second test module 300 refers to the closed high-voltage test circuit formed by the high-voltage output terminal of the second test power supply, the third electrode 310, the conductor insulation layer 130 of the sample under test 100, the first electrode 210, the current limiting protection unit 330, and the grounding terminal of the second test power supply. The current limiting protection unit 330 is connected in series on the high-voltage side or low-voltage side of the power supply circuit of the second test module 300, and participates in the entire breakdown test process to limit and monitor the circuit current throughout the entire process.

[0100] The breakdown of the inter-conductor insulation layer 130 refers to the irreversible damage to the insulation structure of the inter-conductor insulation layer 130 during the voltage boosting process of the second insulation performance test, as the second test voltage gradually increases. The insulation resistance drops instantaneously from a high resistance state to a low resistance conduction state, and the leakage current of the circuit undergoes a sudden change of orders of magnitude. This is the critical state in which the insulation layer loses its withstand voltage capability, and it is also the judgment condition for the current limiting protection unit 330 to trigger the protection action.

[0101] The continuous overcurrent state refers to the state in which the high voltage power supply continuously outputs a large current far exceeding the rated value in the low resistance circuit after the insulation layer breaks down. This continuous overcurrent state will cause the power device to overheat and burn out, and the sample to arc and erode. It is an abnormal state that the current limiting protection unit 330 needs to suppress.

[0102] It should be noted that the operating logic of the current limiting protection unit 330 is divided into two stages, which matches the entire process of the breakdown test: The first stage is the voltage boosting process before breakdown. The current limiting protection unit 330 is in a low-loss, low-leakage current state. Its equivalent impedance in series in the circuit is extremely small, and it will not cause a significant voltage division effect on the output voltage of the second test power supply. This ensures that the test voltage applied to both ends of the insulation layer is consistent with the voltage value collected by the second acquisition module 600, thus ensuring the accuracy of the breakdown voltage test. At the same time, the second acquisition module 600 can collect leakage current data in the circuit in real time and monitor the state changes of the insulation layer.

[0103] The second stage is the instant of breakdown. When the insulation layer breaks down and the circuit current spikes instantaneously, the high-power current-limiting resistor in the current-limiting protection unit 330 will immediately limit the circuit current to within the preset safety threshold. This can suppress the generation of current spikes from the source and avoid the impact of large current on the power supply. At the same time, the fast fuse will cut off the circuit at the instant of continuous overcurrent to prevent the short-circuit arc from continuing to burn and protect the test sample 100 from being burned. The high-speed shutdown circuit will simultaneously send a cutoff signal to the second test power supply to stop the high-voltage output.

[0104] In this way, the output current of the second test power supply can be quickly limited at the moment the insulation layer breaks down, suppressing the continuous overcurrent state after the breakdown and avoiding damage to precision equipment such as the test power supply and data acquisition module by large current surges, thereby reducing the wear and maintenance costs of the test equipment. At the same time, it can prevent the sample under test 100 from being burned by the large current after breakdown, preserving the failure state of the insulation and not affecting the voltage stability and data acquisition accuracy during the boost process before breakdown.

[0105] Please refer to the following: Figure 5 In some embodiments, the insulation performance testing device 1000 further includes a loop isolation unit 500, which is disposed between the second test module 300 and the first test module 200 to achieve electrical isolation between the test circuit of the second test module 300 and the heating circuit of the first test module 200; the loop isolation unit 500 is connected to the heating circuit of the first test module 200. The loop isolation unit 500 is configured to disconnect the electrical connection between the heating power supply 230 of the second test module 300 and the first test module 200, so as to achieve electrical isolation between the first test module 200 and the second test module 300.

[0106] Specifically, the loop isolation unit 500 refers to a hardware unit specifically designed to achieve electrical isolation between the first test module 200 and the second test module 300. It is located between the test circuit and the heating circuit and is typically composed of a high-voltage vacuum relay, a high-voltage disconnect switch, or other switching devices with high isolation withstand voltage. During the first insulation performance test, the loop isolation unit 500 prevents the test circuit from affecting the heating circuit and the heating circuit from interfering with the test data acquisition. During the second insulation performance test, the loop isolation unit 500 disconnects the electrical connection between the second test module 300 and the heating circuit of the first test module 200, preventing high-voltage test voltage and breakdown current from entering the first test module 200, thereby protecting the safety of the heating power supply 230, the current monitoring unit 240, and related data acquisition equipment.

[0107] The heating circuit of the first test module 200 refers to a high-current heating closed circuit composed of the heating power supply 230, the first electrode 210, the first conductor 110, and the second electrode 220, and is the object of isolation by the circuit isolation unit 500. The function of the circuit isolation unit 500 is to cut off all direct electrical connection paths between the second test module 300 and this heating circuit.

[0108] Electrical isolation means that there is no direct conductive path between the heating circuit and the test circuit. Signal transmission between the circuits is achieved only through coupling via non-conductive media such as light and magnetism. The grounding systems of the heating circuit and the test circuit are independent of each other and there is no common grounding point, which can block the direct intrusion of voltage and current and the coupling transmission of interference.

[0109] Thus, the circuit isolation unit 500 is directly connected to the heating circuit of the first test module 200, which can cut off the electrical connection path between the second test module 300 and the heating power supply 230, and realize reliable electrical isolation between the heating circuit and the test circuit from the hardware level.

[0110] Please see Figure 7 This application also provides an insulation performance testing method, which is implemented based on the above-described insulation performance testing device 1000, and includes: 01: Based on the first test module, a preset current is applied to the first conductor to raise the temperature of the first conductor, thereby simulating the rapid heating condition of a superconducting magnet in the process of not alleviating quench loss; 02: During the continuous application of the preset current, the sample under test is intermittently connected through the second test module to perform the first insulation performance test on the sample under test; 03: When the first test module terminates the application of the preset current and the sample under test meets the first temperature condition, the second test module performs a second insulation performance test on the sample under test.

[0111] Specifically, based on the first test module 200, a preset current is applied to the first conductor 110 to continuously heat it up, simulating the rapid heating condition of a superconducting magnet before quench relief. In this step, the heating power supply 230 continuously outputs the preset current to ensure uninterrupted heating. The current monitoring unit 240 collects loop current data in real time, and the temperature sensor collects temperature data of the first conductor 110 in real time. The first acquisition module 400 simultaneously stores full-cycle data of heating current, voltage, temperature, and duration, providing a data foundation for subsequent test data correlation analysis.

[0112] Next, while the preset current is continuously applied and the first conductor 110 is in a rapid heating state, the second test module 300 intermittently connects to the sample under test 100 to perform the first insulation performance test on the sample. In this step, the control module 700 controls the first test power supply to intermittently connect to the test circuit through the isolation switching unit. Each connection time is extremely short to avoid affecting the current distribution and temperature rise process of the heating circuit. At the same time, the second acquisition module 600 synchronously acquires test voltage and leakage current data, calculates and stores the insulation resistance value in real time, adds a timestamp corresponding to temperature and heating time to each set of data, records the evolution characteristics of insulation resistance throughout the rapid heating process, and plots the corresponding curve of insulation resistance-temperature-time.

[0113] Subsequently, after the first test module 200 terminates the application of the preset current and the sample 100 meets the first temperature condition, the second test module 300 performs a second insulation performance test on the sample, that is, gradually increasing the test voltage until the insulation layer breaks down. In this step, the control module 700 first terminates the output of the heating power supply 230 according to the preset heating termination conditions (i.e., reaching the preset heating time, target temperature, or insulation resistance dropping to the preset range), and at the same time, the control circuit isolation unit 500 cuts off the electrical connection between the heating circuit and the test circuit. Then, it quickly switches to the second test power supply, and while the sample temperature has not dropped significantly, it gradually increases the test voltage according to the preset boost rate, and the second acquisition module 600 synchronously acquires the voltage and current data of the circuit throughout the process. When a sudden current change or insulation breakdown is detected, the breakdown voltage value is immediately latched, the high voltage output is stopped, and the current limiting protection unit 330 synchronously triggers the current limiting protection action.

[0114] Thus, a preset current is applied through the first test module 200 to simulate the rapid heating condition of a superconducting magnet without quench relief. Then, during the continuous heating process, the sample is intermittently connected through the second test module 300 to complete the periodic insulation performance test. Finally, when heating is terminated and the sample is still at a high temperature, the breakdown voltage test is completed through the second test module 300. In this way, the simulation of the extreme condition of the superconducting magnet without quench relief and the entire process of insulation performance testing can be seamlessly integrated, and the dynamic electrical performance evolution characteristics of the insulating material during rapid heating, as well as the true withstand voltage limit at high temperature, can be obtained.

[0115] Please see Figure 8 In some implementations, step 01 includes: 011: Based on the first test module, a preset current is applied to the first conductor so that the first conductor heats up to the target temperature within a preset time.

[0116] Specifically, before the test is started, the core thermal history parameters of the target superconducting magnet during the unrelieved quench process are obtained through simulation calculation or fault measurement, and the preset time and target temperature that match the actual working conditions are extracted.

[0117] Subsequently, based on the physical parameters and thermal boundary conditions of the first conductor 110, a preset current amplitude that can heat the first conductor 110 to the target temperature within a preset time is calculated, and the parameters are input into the heating power supply 230 and control module 700 of the first test module 200.

[0118] After the insulation performance testing device 1000 starts testing, the first testing module 200 continuously applies a preset current to the first conductor 110, and at the same time, the temperature data of the first conductor 110 is collected in real time by the temperature sensor, and the current data of the heating circuit is collected in real time by the current monitoring unit 240 and uploaded to the control module 700 simultaneously.

[0119] The control module 700 receives real-time data such as current and temperature from the first acquisition module 400 and dynamically adjusts the output of the heating power supply 230 based on a preset control strategy. This makes the temperature rise process of the first conductor 110 statistically approximate the temperature rise characteristic curve of the target quench condition, thereby achieving equivalent simulation of the operating condition. Simultaneously, throughout the heating process, the control module 700 triggers the second test module 300 to intermittently connect to the sample under test 100 at preset intervals, collecting real-time insulation resistance data of the insulation layer 130 between conductors, forming an evolution curve of insulation performance with temperature and heating time. When the heating time reaches the preset time and the real-time temperature of the first conductor 110 reaches the target temperature, the control module 700 triggers a heating termination action, entering the subsequent second insulation performance test stage.

[0120] In this way, the temperature rise rate, heating time and target temperature during the unrelieved quench process of the superconducting magnet can be reproduced, ensuring that the test conditions match the real fault scenario, and making the insulation performance test results have strong engineering applicability and reference value.

[0121] Please see Figure 9 In some implementations, the method further includes: 04: Based on the first acquisition module, acquire and store the current data in the power supply circuit of the first test module, the output voltage data of the heating power supply, and the temperature data of the first conductor.

[0122] Specifically, the moment the first test module 200 applies the preset current and starts the heating process, the first acquisition module 400 simultaneously triggers acquisition, running continuously until the entire test process terminates. During acquisition, the first acquisition module 400 acquires current data of the heating circuit and output voltage data of the heating power supply 230 through isolated sampling, and acquires real-time temperature data of the first conductor 110 through a temperature sensor. Furthermore, all raw signals, after filtering, conditioning, and analog-to-digital conversion, are bound with a synchronous timestamp and written to the storage medium in real time, while simultaneously being transmitted to the control module 700. Based on the real-time acquired data, the control module 700 adjusts the output of the heating power supply 230 in a closed loop to ensure stable application of the preset current and that the temperature rise process matches the preset operating conditions. Simultaneously, it monitors in real time whether the current and temperature data exceed the preset safety test thresholds, triggering protection actions promptly in case of abnormalities.

[0123] After the test is completed, the full-cycle time-series data stored in the first acquisition module 400 can be aligned with the insulation resistance and breakdown voltage data acquired by the second test module 300 on the time axis to construct a mapping relationship of "heating input - temperature rise history - insulation performance evolution", providing data support for subsequent analysis and evaluation.

[0124] In this way, operating parameters throughout the entire heating process can be recorded, enabling traceability of key parameters during the test. Furthermore, it allows for the establishment of a correlation between temperature rise curves, current changes, and insulation performance evolution, providing fundamental data for analyzing insulation degradation patterns. In addition, it enables real-time monitoring of abnormal operating conditions during the heating process, providing real-time data support for the heating termination protection logic and ensuring the controllability and stability of the test process.

[0125] Please see Figure 10 In some implementations, step 02 includes: 021: Based on the second test module, during the continuous application of the preset current, the first test power supply is intermittently connected to the sample under test, and the first test voltage is applied to the sample under test to perform the first insulation performance test.

[0126] Specifically, the test process of the second test module 300 is triggered synchronously the instant the first test module 200 starts applying the preset current and initiating the heating process. Throughout the heating process, the control module 700 periodically sends a conduction command to the isolation switching unit according to preset timing parameters, connecting the first test power supply between the first electrode 210 and the third electrode 310 of the sample under test 100, applying a stable first test voltage to the interconductor insulation layer 130, and performing the first insulation performance test. It should be noted that throughout the test process, the control module 700 dynamically adjusts the test connection interval based on the real-time collected insulation resistance and temperature data. For example, when the insulation resistance is in a high-resistance stable state, a longer connection interval is used to reduce the impact of the test connection on the heating process.

[0127] Since the output voltage amplitude of the first test power supply is low and the test duration is short, and the test circuit adopts a high impedance connection method, it does not have a significant impact on the heating current distribution of the first test module 200.

[0128] In this way, by using a low-voltage, non-destructive testing method, non-destructive periodic testing of insulation resistance is achieved during continuous heating. This not only avoids premature insulation breakdown and ensures continuous and stable heating process, but also obtains the dynamic evolution characteristics of insulation resistance with temperature and time. Furthermore, it effectively avoids electrical interference from the test voltage to the heating circuit, ensuring the realism of the operating condition simulation and the accuracy of the test data.

[0129] Please see Figure 11 In some implementations, the method further includes: 05: Based on the second acquisition module, the insulation resistance data of the insulation layer between conductors, as well as the test voltage data and test current data corresponding to the second test module during the test process, are collected and stored during the first insulation performance test.

[0130] Specifically, after the first test module 200 starts heating and the first conductor 110 enters rapid heating mode, the second test module 300 intermittently connects to the sample under test 100 according to a preset timing sequence. Each time the isolation switching unit is turned on and the first test voltage is applied by the first test power supply, the second acquisition module 600 synchronously triggers high-frequency acquisition, continuously acquiring raw data of the test voltage and test current throughout the entire conduction window. The raw data can be digitally filtered to remove noise fluctuations caused by electromagnetic interference, and stable effective values ​​of voltage and current can be calculated. Subsequently, based on Ohm's law, the insulation resistance of the insulation layer 130 between conductors within the test window is calculated in real time. Finally, the voltage data, current data, and insulation resistance data of this test, bound with a synchronization timestamp, the corresponding heating duration, and the real-time temperature data of the first conductor 110, are written to a non-volatile storage medium. All data processing and storage for a single test are completed before the circuit is disconnected.

[0131] In this way, insulation performance data can be collected in real time and continuously throughout the entire heating process, recording the dynamic evolution of insulation resistance. Furthermore, a one-to-one correspondence can be established with the temperature and current data from the first acquisition module 400, constructing a multi-parameter mapping model of insulation resistance-temperature-time, providing experimental data support for subsequent analysis and research.

[0132] Please see Figure 12 In some implementations, the method further includes: 06: Based on the control module, when the heating time of the first conductor reaches the preset heating time, or when the real-time temperature of the first conductor reaches the target temperature, the first test module is controlled to terminate the application of the preset current.

[0133] Specifically, after the test is started, the first test module 200 begins to apply a preset current, and the control module 700 simultaneously starts timing. At the same time, it reads the real-time temperature data of the first conductor 110 uploaded by the first acquisition module 400 and continuously performs logical comparisons. When the heating time reaches the preset value, or the real-time temperature reaches the target temperature, the control module 700 immediately sends a stop command to the heating power supply 230, cutting off the preset current output and terminating the heating process. Simultaneously, after confirming that the sample 100 under test meets the first temperature condition, it sends a ready command to the second test module 300, preparing for the subsequent breakdown test.

[0134] In this way, the heating process can be controlled according to the preset quench condition to ensure the repeatability and consistency of multiple parallel tests. It can also terminate the heating in time according to the real-time deterioration of the insulation resistance, capture the key node of the sudden change in insulation performance, and avoid test failure caused by overheating of the sample.

[0135] Please see Figure 13 In some implementations, step 03 includes: 031: Based on the second test module, under the action of the second test power supply, a second test voltage with gradually increasing amplitude is applied to the sample under test to perform a withstand voltage test on the insulation layer between conductors until breakdown occurs.

[0136] Specifically, after the control module 700 confirms that the sample 100 under test meets the first temperature condition, the electrical connection between the test circuit and the heating power supply 230 is cut off through the loop isolation unit 500, and the second test module 300 is switched to the second test power supply. At the same time, the boost rate, breakdown judgment parameters and protection threshold are set.

[0137] Subsequently, the second test power supply is controlled to output a gradually increasing second test voltage at a preset rate, and the second acquisition module 600 synchronously acquires real-time voltage, current, and other data of the test circuit at a high-frequency sampling rate. When an abnormal jump in the current in the test circuit is detected, and the voltage drop rate, current change duration, and insulation resistance estimation results meet the preset comprehensive criteria, it is determined that the insulation layer 130 between conductors has broken down. The high-voltage output is simultaneously cut off, and the instantaneous breakdown voltage value is locked.

[0138] Thus, by completing the breakdown voltage test while the insulation is still at a high temperature after heating is stopped, the insulation condition deviation caused by cooling and reheating can be avoided, thereby enabling the breakdown voltage obtained from the test to reflect the true withstand voltage limit of the insulation under quench conditions.

[0139] This application also provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, it performs the steps of the method described above.

[0140] It is understood that a computer program includes computer program code. Computer program code can be in the form of source code, executable files in the form of object code, or some intermediate form. Computer-readable storage media can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, external hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), and software distribution media, etc.

[0141] This application also provides a computer program product, including a computer program / instructions that, when executed by a processor, implement the above-described method.

[0142] In this specification, the terms "specifically," "furthermore," "particularly," "understandably," etc., refer to specific features, structures, materials, or characteristics described in connection with embodiments or examples that are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0143] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of executable request code comprising one or more steps for implementing a particular logical function or process, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0144] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. An insulation performance testing device simulating the rapid heating process of a superconducting magnet without quench relief, characterized in that, The insulation performance testing device includes a sample to be tested, a first testing module, and a second testing module, wherein the first testing module and the second testing module are electrically isolated. The test sample includes a first conductor and a second conductor that are mutually insulated and isolated from each other, and an inter-conductor insulation layer disposed between the first conductor and the second conductor. The cross-sectional dimensions of the first conductor and the second conductor are both matched with the cross-sectional dimensions of the conductor used in the superconducting magnet. The first insulation structure of the inter-conductor insulation layer is consistent with the structure of the inter-turn insulation layer of the superconducting magnet. The first test module includes a first electrode and a second electrode, wherein the first electrode is connected to a first end of the first conductor and the second electrode is connected to a second end of the first conductor; The second test module includes a first electrode shared with the first test module, and a third electrode connected to the second conductor; The first test module is configured to apply a preset current to the first conductor to heat up the first conductor, thereby simulating the rapid heating condition of the superconducting magnet during the unrelieved quench process. The preset current is continuously applied and remains uninterrupted during the test. The second test module is configured to intermittently connect to the sample under test during the application of the preset current, so as to realize intermittent periodic insulation performance testing; The second test module selectively connects or disconnects from the sample under test via an isolation switching unit, so that the measurement circuit does not affect the application of the preset current of the first test module when it is connected. The second test module is configured to perform a first insulation performance test on the sample under test when the sample under test is under the rapid heating condition, and to perform a second insulation performance test on the sample under test when the first test module terminates the application of the preset current and the sample under test meets the first temperature condition, wherein the first temperature condition is used to characterize that the temperature of the first conductor is greater than or equal to the preset temperature.

2. The insulation performance testing device according to claim 1, characterized in that, The test sample also includes a ground insulation layer, which covers the outer surfaces of the first conductor and the second conductor.

3. The insulation performance testing device according to claim 1, characterized in that, The first test module further includes a heating power supply, a current monitoring unit, and an overcurrent protection unit. The heating power supply is electrically connected to the first electrode and the second electrode, respectively. The current monitoring unit is connected to the power supply circuit of the first test module, and the overcurrent protection unit is electrically connected to the heating power supply. The heating power supply is configured to output the preset current to the first conductor so that the first conductor heats up to the target temperature within a preset time. The preset time and the target temperature are both matched with the rapid heating condition of the superconducting magnet during the unrelieved quench process. The current monitoring unit is configured to monitor the current data in the power supply circuit of the first test module; The overcurrent protection unit is configured to trigger a protection action when the current data monitored by the current monitoring unit is greater than or equal to a preset current threshold, thereby limiting or cutting off the output of the heating power supply to suppress the overcurrent state and ensure the normal execution of the intermittent insulation test process of the second test module.

4. The insulation performance testing device according to claim 3, characterized in that, The insulation performance testing device further includes a first acquisition module, which is electrically connected to the first testing module based on an isolated sampling method. The first acquisition module is configured to acquire and store current data in the power supply circuit of the first test module, output voltage data of the heating power supply, and temperature data of the first conductor.

5. The insulation performance testing device according to claim 4, characterized in that, The second test module further includes a test power supply unit, which is electrically connected to the first electrode and the third electrode respectively. The test power supply unit includes a first test power supply and a second test power supply. The second test module is configured to intermittently connect to the sample under test through the first test power supply during the rapid heating condition and the first test module continuously applies the preset current to the first conductor, so as to apply the first test voltage to perform the first insulation performance test. Wherein, the amplitude of the first test voltage is lower than the preset safe test voltage threshold of the insulation layer between the conductors, so as to avoid causing a breakdown. After the first test module terminates the application of the preset current and the sample under test meets the first temperature condition, the second test module switches to the second test power supply and applies a second test voltage with gradually increasing amplitude to the sample under test to perform the second insulation performance test. The voltage amplitude of the second test voltage is greater than the voltage amplitude of the first test voltage.

6. The insulation performance testing device according to claim 5, characterized in that, The insulation performance testing device further includes a second acquisition module, which is electrically connected to the second testing module. The second acquisition module is configured to acquire and store the insulation resistance data of the inter-conductor insulation layer during the first insulation performance test; And the second test module tests the voltage and current data in the circuit during the second insulation performance test; And during the second insulation performance test, the breakdown voltage data corresponding to the gradual increase of the output voltage of the second test power supply until the insulation layer between the conductors breaks down.

7. The insulation performance testing device according to claim 6, characterized in that, The insulation performance testing device further includes a control module, which is electrically connected to the first acquisition module, the first test module, the second acquisition module, and the second test module, respectively. The control module is configured to: When the heating time of the first conductor reaches the preset heating time, or when the real-time temperature of the first conductor reaches the target temperature, the first test module is controlled to terminate the application of the preset current; and when the insulation resistance parameter of the insulation layer between the conductors drops to the preset resistance range, an early warning signal is generated. When there is an abnormality in the current data in the power supply circuit of the first test module or the temperature data of the first conductor, the first test module is controlled to terminate the application of the preset current.

8. The insulation performance testing device according to claim 6, characterized in that, The second test module also includes a current limiting protection unit, which is connected in series in the power supply circuit of the second test module; The current limiting protection unit is configured to limit the output current of the second test power supply when a breakdown of the insulation layer between the conductors is detected during the second insulation performance test, so as to suppress the continuous overcurrent state in the power supply circuit after the breakdown and protect the test power supply unit and the sample under test.

9. The insulation performance testing device according to claim 1, characterized in that, The insulation performance testing device further includes a circuit isolation unit, which is disposed between the second test module and the first test module to achieve electrical isolation between the test circuit of the second test module and the heating circuit of the first test module. The circuit isolation unit is connected to the heating circuit of the first test module; The circuit isolation unit is configured to disconnect the electrical connection between the heating circuit of the second test module and the first test module, so as to achieve electrical isolation between the first test module and the second test module.

10. A method for testing insulation performance, characterized in that, The method is implemented based on the insulation performance testing device as described in any one of claims 1-9, and the method includes: Based on the first test module, a preset current is applied to the first conductor to raise the temperature of the first conductor, thereby simulating the rapid heating condition of the superconducting magnet during the unrelieved quench process; During the continuous application of the preset current, the sample under test is intermittently connected through the second test module to perform a first insulation performance test on the sample under test. When the first test module terminates the application of the preset current and the sample under test meets the first temperature condition, the second test module performs a second insulation performance test on the sample under test, wherein the second insulation performance test includes gradually increasing the test voltage until breakdown occurs.

11. The method according to claim 10, characterized in that, The step of applying a preset current to the first conductor based on the first test module to raise the temperature of the first conductor, thereby simulating the rapid temperature rise of the superconducting magnet during the unrelieved quench process, includes: Based on the first test module, a preset current is applied to the first conductor to raise the temperature of the first conductor to the target temperature within a preset time. The preset time and the target temperature are both matched with the rapid heating condition of the superconducting magnet during the unrelieved quench process.

12. The method according to claim 11, characterized in that, The method further includes: Based on the first acquisition module, the current data in the power supply circuit of the first test module, the output voltage data of the heating power supply, and the temperature data of the first conductor are acquired and stored.

13. The method according to claim 11, characterized in that, The test sample is intermittently connected to the second test module to perform a first insulation performance test on the test sample, including: Based on the second test module, during the continuous application of the preset current, the test sample is intermittently connected to the test sample through the first test power supply, and a first test voltage is applied to the test sample to perform the first insulation performance test. The amplitude of the first test voltage is lower than the preset safety test threshold of the inter-conductor insulation layer to avoid breakdown of the inter-conductor insulation layer.

14. The method according to claim 10, characterized in that, When the first test module terminates the application of the preset current and the sample under test meets the first temperature condition, the second test module performs a second insulation performance test on the sample under test, including: Based on the second test module, under the action of the second test power supply, a second test voltage with gradually increasing amplitude is applied to the sample under test to perform a withstand voltage test on the insulation layer between the conductors until breakdown occurs; The second test voltage gradually exceeds the first test voltage during the voltage boosting process.

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