Insulation resistance monitoring device and method and storage medium

Abstract

The invention relates to the technical field of insulation detection, and discloses an insulation resistance monitoring device and method and a storage medium, the insulation resistance monitoring device comprises a signal processing module, a control module and an insulation monitoring circuit connected with the signal processing module; the insulation monitoring circuit is used for forming an electric leakage detection loop with the electric power circuit to be monitored and the main grounding electrode and outputting real-time electric leakage current in the electric leakage detection loop to the signal processing module; the signal processing module is used for determining a real-time voltage corresponding to the real-time leakage current; the real-time voltage is output to the control module; the control module is used for determining the real-time insulation resistance of the power line to be monitored according to the real-time voltage; and determining whether the insulation state of the to-be-monitored power line is abnormal or not according to the real-time insulation resistance and the target insulation resistance threshold. According to the invention, multi-voltage-level power line insulation monitoring requirements can be met.

Description

Technical Field

[0001] This application relates to the field of insulation testing technology, specifically to insulation resistance monitoring devices, methods, and storage media. Background Technology

[0002] Currently, power system voltage levels cover 380VAC-1140VAC and are continuously increasing, even expanding to 3300VAC. Different voltage levels correspond to different grid insulation resistance setting values. In related technologies, a common approach is to connect the rectifier tube to the three phases of the grid and ground it, and then use a load resistor and current transformer to form a leakage current detection circuit to collect the leakage current. When the current rises to the set value, the protection device is triggered to operate, thus achieving leakage protection. However, this type of solution has significant drawbacks. Firstly, for different voltage level systems, the load resistance needs to be adjusted separately to match the protection setting value, resulting in poor adaptability, cumbersome operation, and incompatibility with the expansion needs of multi-voltage level power grids. Summary of the Invention

[0003] In view of the above, in a first aspect, this application provides an insulation resistance monitoring device, the insulation resistance monitoring device comprising: The system includes a signal processing module, a control module, and an insulation monitoring circuit connected to the signal processing module; the control module is pre-set with insulation resistance thresholds corresponding to different voltage levels. The insulation monitoring circuit is used to form a leakage current detection loop with the power line to be monitored and the main grounding electrode, and output the real-time leakage current in the leakage current detection loop to the signal processing module. The signal processing module is used to determine the real-time voltage corresponding to the real-time leakage current and output the real-time voltage to the control module. The control module is used to determine the real-time insulation resistance of the power line to be monitored based on the real-time voltage; and to determine whether there is an abnormality in the insulation status of the power line to be monitored based on the real-time insulation resistance and the target insulation resistance threshold; wherein the target insulation resistance threshold is the insulation resistance threshold corresponding to the voltage level of the power line to be monitored.

[0004] This embodiment establishes a collaborative architecture of insulation monitoring circuit, signal processing module, and control module. The control module presets insulation resistance thresholds corresponding to different voltage levels. The insulation monitoring circuit, the power line under test, and the main grounding electrode form a leakage current detection loop and output real-time leakage current. This current is converted into real-time voltage by the signal processing module and transmitted to the control module. The control module then calculates the real-time insulation resistance based on the real-time voltage and determines the insulation status by combining this with the target insulation resistance threshold corresponding to the voltage level of the power line under test. This embodiment, by presetting graded insulation resistance thresholds, can adapt to the monitoring needs of power lines at different voltage levels without adjusting hardware, solving the problems of poor adaptability and cumbersome operation in traditional solutions. Furthermore, through the acquisition, conversion, and insulation resistance calculation of real-time leakage current, the real-time insulation resistance value of the power line under test can be accurately obtained, enabling accurate and real-time determination of whether there are abnormalities in the insulation status, effectively improving the adaptability and accuracy of insulation monitoring for power lines at multiple voltage levels.

[0005] In one optional embodiment, the device further includes: an analog leakage current monitoring circuit connected to the signal processing module; The control module is further configured to determine the simulated leakage current based on the target insulation resistance threshold, generate a first control command based on the simulated leakage current, and send the first control command to the simulated leakage monitoring circuit. The simulated leakage current monitoring circuit is used to generate the simulated leakage current according to the first control command and output it to the signal processing module. The signal processing module is further configured to determine the analog voltage corresponding to the analog leakage current and output the analog voltage to the control module. The control module is also used to determine whether the insulation resistance monitoring device is faulty based on the analog voltage.

[0006] This embodiment adds a simulated leakage current monitoring circuit connected to the signal processing module. The control module determines the simulated leakage current based on the target insulation resistance threshold of the power line to be monitored and generates a first control command. The simulated leakage current monitoring circuit generates and outputs the simulated leakage current according to the command. This simulated current is converted into an analog voltage by the signal processing module and fed back to the control module. The control module then determines whether the device itself has a fault based on the simulated voltage. This embodiment constructs a complete self-test loop for the device. By generating a simulated leakage current that matches the actual monitoring scenario, the effectiveness of each module of the insulation resistance monitoring device is verified in reverse. This allows for timely detection of faults in the device itself, avoiding inaccurate monitoring and protection failures caused by device malfunctions. Furthermore, the matching of the simulated leakage current with the target insulation resistance threshold ensures that the self-test process meets the monitoring requirements of different voltage levels, improving the accuracy of the self-test results and guaranteeing the stability and reliability of the overall monitoring function of the device.

[0007] In one optional embodiment, the device further includes an execution module connected to the control module; The control module is also used to generate a high-level signal and send the high-level signal to the execution module when there is an abnormality in the insulation state of the power line to be monitored; The execution module is used to disconnect the power line to be monitored when it receives the high-level signal.

[0008] This embodiment adds an execution module connected to the control module. When the control module determines that the insulation state of the monitored power line is abnormal, it generates and sends a high-level signal to the execution module. Upon receiving the high-level signal, the execution module immediately disconnects the monitored power line. Based on accurate insulation state determination, this embodiment adds an active fault handling step, realizing closed-loop control of monitoring, determination, and protection. This changes the traditional solution's limitation of only monitoring without active protection. The high-level signal transmission method has a fast response speed, enabling the execution module to act quickly when the insulation state is abnormal, promptly disconnecting the faulty line. This effectively prevents safety accidents such as leakage and short circuits caused by a continuous decrease in insulation resistance, significantly improving the safety and timeliness of protection of the monitored power line.

[0009] In one optional implementation, the execution module includes: The device includes a switching transistor, a relay, and a circuit breaker; the circuit breaker is installed on the power line to be monitored; the relay includes a coil, a first normally open contact, and a second normally open contact. The base of the switching transistor is connected to the control module, and the collector of the switching transistor is connected to the coil of the relay and the first normally open contact, respectively. The second normally open contact of the relay is connected in series with the circuit breaker; The switching transistor is used to conduct when it receives a high-level signal from the control module, thereby energizing the coil of the relay, causing the first normally open contact and the second normally open contact to close, the circuit breaker to open, and the power line to be monitored to disconnect.

[0010] This embodiment configures the execution module as a combination of a switching transistor, a relay, and a circuit breaker. The base of the switching transistor is connected to the control module, and its collector is connected to the relay coil and the first normally open contact. The second normally open contact of the relay is connected in series with the circuit breaker. The switching transistor receives a high-level signal and conducts, energizing the relay coil to close the normally open contact, thereby triggering the circuit breaker to disconnect the monitored power line. This hardware structure achieves precise linkage between electrical signals and mechanical actions. The switching transistor can quickly respond to high-level signals from the control module, ensuring timely protection actions. The normally open contact design of the relay enables self-locking after the coil is energized, ensuring the circuit breaker stably disconnects the faulty line. The circuit breaker is directly installed on the monitored power line, reliably cutting off the line current. The overall structure has clear logic and precise coordination, improving the stability, timeliness, and reliability of fault line disconnection operations.

[0011] In one optional implementation, the execution module further includes a reset button; The control module is also used to generate a reset signal and send the reset signal to the reset button when the insulation state of the power line to be monitored returns to normal. The reset button is used to disconnect when a reset signal is received from the control module, thereby de-energizing the relay coil, causing the first normally open contact and the second normally open contact to open, closing the circuit breaker, and enabling the monitored power line to conduct.

[0012] This embodiment adds a reset button to the execution module. When the insulation state of the monitored power line returns to normal, the control module generates a reset signal and sends it to the reset button. Upon receiving the signal, the reset button disconnects, de-energizing the relay coil and opening the normally open contact, thereby triggering the circuit breaker to close and restore line continuity. This embodiment achieves intelligent reset of the faulty line, eliminating the need for manual operation of the circuit breaker and improving the convenience of power restoration. Furthermore, the reset signal is generated by the control module based on real-time insulation resistance determination, ensuring that reset is triggered only when the insulation state is truly restored to normal, avoiding accidental resets when the fault is not yet resolved, and improving reset safety. Simultaneously, the linkage between the reset button, relay, and circuit breaker improves the line control process for abnormal disconnection and normal reset, making the entire protection system more complete and intelligent.

[0013] In one optional implementation, the signal processing module includes: Sampling resistor, filtering unit, and signal amplification unit; The filtering unit is connected to the insulation monitoring circuit and is used to filter the real-time leakage current and input the filtered real-time leakage current into the sampling resistor. The sampling resistor is used to convert the received real-time leakage current into a corresponding real-time voltage and output the real-time voltage to the signal amplification unit; The signal amplification unit is used to amplify the real-time voltage and output the amplified real-time voltage to the control module.

[0014] This embodiment of the application specifically configures the signal processing module as a combination of a sampling resistor, a filtering unit, and a signal amplification unit. The filtering unit filters the received real-time leakage current, filters out interference, and converts it into a real-time voltage after input to the sampling resistor. This voltage is then amplified by the signal amplification unit and output to the control module. The filtering unit effectively filters out noise interference in the leakage detection circuit, preventing interference signals from affecting the accuracy of voltage conversion and laying a reliable current basis for subsequent insulation resistance calculation. The sampling resistor achieves accurate current-to-voltage conversion, converting physical current into an electrical signal that the control module can recognize. The signal amplification unit amplifies the weak real-time voltage, adapting it to the signal acquisition threshold of the control module, avoiding judgment errors caused by insufficient voltage. Each unit processes the signal step by step with a clear division of labor, significantly improving the accuracy of signal conversion and ensuring the accuracy of the insulation status determination by the control module.

[0015] In one optional implementation, the insulation monitoring circuit includes: First power supply, three-phase reactor and first capacitor; The first power supply is used to output the detection voltage. The positive terminal of the first power supply is connected to the main ground terminal, and the negative terminal of the first power supply is grounded. The three-phase reactor is connected to the power line to be monitored and the first capacitor respectively, and is connected to the main grounding electrode through the first capacitor; The connection point between the three-phase reactor and the first capacitor is connected to the signal processing module.

[0016] This embodiment of the application configures the insulation monitoring circuit as a combination of a first power supply, a three-phase reactor, and a first capacitor. The first power supply outputs a detection voltage, with its positive terminal connected to the main grounding electrode and its negative terminal grounded. The three-phase reactor connects the power line to be monitored to the first capacitor, and the first capacitor is connected to the main grounding electrode. The connection point between the two is connected to the signal processing module. The first power supply provides a stable DC detection voltage for the leakage current detection circuit, ensuring the continuous operation of the detection work. The three-phase reactor is adapted to the monitoring requirements of three-phase power lines, while effectively suppressing harmonic interference in the power grid and improving the stability of the detection circuit. The first capacitor and the three-phase reactor work together to form a high-resistance ground, providing a reliable path for real-time leakage current and avoiding the short-circuit risk caused by direct grounding. The overall structure can stably construct a leakage current detection circuit that matches the power line to be monitored, accurately collect real-time leakage current, and provide high-quality hardware support for subsequent signal processing and insulation status determination.

[0017] Secondly, this application also provides an insulation resistance monitoring method, applied to the insulation resistance monitoring device of the first aspect or any corresponding embodiment thereof, comprising: Obtain the real-time leakage current in the leakage detection circuit; Determine the real-time voltage corresponding to the real-time leakage current; The real-time insulation resistance of the power line to be monitored is determined based on the real-time voltage. The insulation status of the power line to be monitored is determined based on the real-time insulation resistance and the target insulation resistance threshold; the target insulation resistance threshold is the insulation resistance threshold corresponding to the voltage level of the power line to be monitored.

[0018] In one optional implementation, the method further includes: The simulated leakage current is determined based on the target insulation resistance threshold. Determine the analog voltage corresponding to the simulated leakage current; The presence of a fault in the insulation resistance monitoring device is determined based on the simulated voltage.

[0019] Thirdly, this application also provides a computer-readable storage medium storing computer instructions that cause a computer to perform the method described in the second aspect or any of its corresponding embodiments. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the insulation resistance monitoring device according to an embodiment of this application; Figure 2 This is a schematic diagram of the specific structure of the insulation resistance monitoring device according to an embodiment of this application; Figure 3 This is a flowchart illustrating the insulation resistance monitoring method according to an embodiment of this application.

[0022] In the diagram: Signal processing module-1, sampling resistor-11, filtering unit-12, signal amplification unit-13, control module-2, insulation monitoring circuit-3, first power supply-31, three-phase reactor-32, first capacitor-33, analog leakage current monitoring circuit-4, second power supply-41, test button-42, execution module-5, switching transistor-51, relay-52, first normally open contact 521, second normally open contact 522, circuit breaker-53, first resistor-54 and first diode-55, reset button-56. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0025] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. They can refer to a mechanical connection or an electrical connection. They can refer to a direct connection or an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0026] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0027] In related technologies, three rectifier diodes are connected to the three phases of the power grid, with the other ends connected together and grounded. The system monitors the insulation of a three-phase, three-wire power supply system with a voltage level of 3.3kV and below in the mine. Current is collected, and once the current rises to a set value, the protection device activates, providing leakage current protection.

[0028] The above solution has the following drawbacks: 1. For systems with different voltage levels, the load resistance needs to be adjusted separately.

[0029] 2. Lacks self-test settings, unable to measure insulation resistance in real time.

[0030] This application provides an insulation resistance monitoring device to solve the above-mentioned problems. This application pre-sets insulation resistance thresholds corresponding to different voltage levels in the control module, and combines an insulation monitoring circuit and a signal processing module to complete real-time leakage current acquisition and insulation resistance calculation. It can adapt to systems of different voltage levels without adjusting the hardware load, solving the problems of traditional solutions requiring separate load resistance adjustment and poor adaptability. Simultaneously, a simulated leakage current monitoring circuit is added, which can generate a matching simulated leakage current based on the target insulation resistance threshold to complete the device's self-test. Furthermore, it can calculate and feed back the real-time insulation resistance value of the power grid through the control module, solving the problems of traditional solutions lacking self-test settings and being unable to measure insulation resistance values ​​in real time. This achieves multi-voltage level adaptation and accurate, real-time monitoring of insulation status.

[0031] Figure 1 This is a schematic diagram of the insulation resistance monitoring device according to an embodiment of this application.

[0032] like Figure 1 As shown in the figure, this application embodiment provides an insulation resistance monitoring device, which includes: The system includes a signal processing module 1, a control module 2, and an insulation monitoring circuit 3 connected to the signal processing module 1. The control module 2 has pre-set insulation resistance thresholds corresponding to different voltage levels.

[0033] In this embodiment, the insulation resistance is the equivalent insulation resistance of the power line to be monitored to ground, which reflects the insulation performance of the power line to be monitored. The value of the insulation resistance characterizes the degree of insulation integrity of the line insulation layer. The higher the value, the better the insulation performance of the line and the lower the risk of leakage. The lower the value, the worse the insulation performance of the line, and the easier it is to generate leakage current to ground, which may pose safety hazards such as leakage and short circuit.

[0034] In this embodiment, the control module 2 is a microcontroller unit (MCU). This MCU integrates analog-to-digital conversion, digital-to-analog conversion, data processing, and instruction generation functions, serving as the core control unit of the entire device. It can perform electrical signal (real-time voltage, analog voltage) acquisition, insulation resistance calculation, status determination, and output of various control commands. In this embodiment, the control module 2 can also be connected to a transceiver, which in turn connects to a background monitoring system. The control module 2 can upload real-time insulation resistance and insulation status determination results (abnormal or normal) of the monitored power line to the background monitoring system via the transceiver, enabling remote visualization of the monitoring data. Simultaneously, it can receive insulation resistance threshold configuration and update commands from the background monitoring system, allowing for remote modification and adaptation of insulation resistance thresholds corresponding to different voltage levels without requiring on-site hardware debugging, thus improving the intelligent operation and maintenance efficiency of the device.

[0035] As an example, the insulation resistance thresholds for different voltage levels are as follows: 62.509 MΩ for 3300VAC; 27.868 MΩ for 1500VAC; 20.939 MΩ for 1140VAC; 6.313 MΩ for 380VAC; and 4.774 MΩ for 300VAC. These thresholds are calculated based on a personal safety protection current of 30mA and a detection voltage of 60VDC, and are suitable for the insulation protection requirements of three-phase three-wire ungrounded neutral power systems.

[0036] Insulation monitoring circuit 3 is used to form a leakage current detection loop with the power line to be monitored and the main grounding electrode, and outputs the real-time leakage current in the leakage current detection loop to the signal processing module 1.

[0037] In this embodiment, the real-time leakage current is the ground leakage current generated by the degradation of insulation performance of the power line under monitoring. This real-time leakage current flows in the leakage detection circuit, and its value is negatively correlated with the equivalent ground insulation resistance of the power line under monitoring. That is, the lower the insulation resistance of the line, the larger the real-time leakage current, and vice versa. The real-time leakage current is a DC microampere-level current, and its value range varies with the line voltage level and insulation state. For example, when the real-time insulation resistance reaches the insulation resistance threshold at a voltage level of 3300VAC, the real-time leakage current is approximately 0.96mA; when the real-time insulation resistance reaches the insulation resistance threshold at a voltage level of 300VAC, the real-time leakage current is approximately 12.57mA. This real-time leakage current can truly reflect the actual insulation state of the line.

[0038] Signal processing module 1 is used to determine the real-time voltage corresponding to the real-time leakage current. The real-time voltage is then output to control module 2.

[0039] In the embodiments of this application, Figure 2 This is a schematic diagram of the specific structure of the insulation resistance monitoring device according to an embodiment of this application, as shown below. Figure 2 As shown, the signal processing module 1 includes a sampling resistor 11, a filtering unit 12, and a signal amplification unit 13. The filtering unit 12 is connected to the insulation monitoring circuit 3 and is used to filter the real-time leakage current, then input the filtered real-time leakage current into the sampling resistor 11. The sampling resistor 11 converts the received real-time leakage current into a corresponding real-time voltage and outputs the real-time voltage to the signal amplification unit 13. The signal amplification unit 13 amplifies the real-time voltage and outputs the amplified real-time voltage to the control module 2.

[0040] In this embodiment, based on Ohm's law U=IR, the real-time leakage current can be converted into the corresponding real-time voltage through the sampling resistor 11, where I is the real-time leakage current after filtering, R is the fixed resistance value of the sampling resistor 11, and U is the real-time voltage generated across the sampling resistor 11. This conversion process is a linear and precise conversion, and the converted real-time voltage is positively correlated with the real-time leakage current. Moreover, the voltage is an electrical signal type that the control module 2 can directly acquire.

[0041] Control module 2 is used to determine the real-time insulation resistance of the power line to be monitored based on the real-time voltage. It then determines whether there are any abnormalities in the insulation status of the power line under monitoring based on the real-time insulation resistance and a target insulation resistance threshold. The target insulation resistance threshold is the insulation resistance threshold corresponding to the voltage level of the power line to be monitored. Different voltage levels correspond to different insulation resistance thresholds.

[0042] In this embodiment, the control module 2 pre-stores a fixed detection voltage U0 (60VDC in this application) for the leakage current detection circuit, and also stores the resistance value R of the sampling resistor 11 of the signal processing module 1 and the amplification factor K of the signal amplification unit 13. The control module 2 first divides the received amplified real-time voltage U1 by the amplification factor K to obtain the original real-time voltage U across the sampling resistor 11. Then, it calculates the filtered real-time leakage current I according to I=U / R. Finally, it calculates the real-time insulation resistance R_insulation of the power line to be monitored according to R_insulation=U0 / I. The entire calculation process is automatically completed by the dedicated calculation program built into the control module 2, with a short calculation response time, enabling rapid calculation of real-time insulation resistance.

[0043] In this embodiment, the control module 2 determines whether the insulation status of the monitored power line is abnormal by comparing the real-time insulation resistance with a target insulation resistance threshold. For example, if the real-time insulation resistance is less than or equal to the target insulation resistance threshold, it is determined that the insulation status of the monitored power line is abnormal, and the insulation performance of the line has dropped below the safety threshold, indicating a risk of leakage or short circuit. If the real-time insulation resistance is greater than the target insulation resistance threshold, it is determined that the insulation status of the monitored power line is normal or not abnormal, and the insulation performance of the line meets the requirements for safe operation.

[0044] This embodiment establishes a collaborative architecture of insulation monitoring circuit 3, signal processing module 1, and control module 2. The control module 2 presets insulation resistance thresholds corresponding to different voltage levels. The insulation monitoring circuit 3, the power line to be monitored, and the main grounding electrode form a leakage current detection loop and output real-time leakage current. This current is converted into real-time voltage by the signal processing module 1 and transmitted to the control module 2. The control module 2 then calculates the real-time insulation resistance based on the real-time voltage and determines the insulation status by combining this with the target insulation resistance threshold corresponding to the voltage level of the power line to be monitored. This embodiment, by presetting graded insulation resistance thresholds, can adapt to the monitoring needs of power lines at different voltage levels without adjusting the hardware, solving the problems of poor adaptability and cumbersome operation of traditional solutions. Furthermore, through the acquisition, conversion, and insulation resistance calculation of real-time insulation leakage current, the real-time resistance value of the power line to be monitored can be accurately obtained, enabling accurate and real-time determination of whether there are abnormalities in the insulation status, effectively improving the adaptability and accuracy of insulation monitoring for power lines at multiple voltage levels.

[0045] In one alternative implementation, the insulation monitoring circuit 3 includes: The first power supply 31, the three-phase reactor 32, and the first capacitor 33.

[0046] In this embodiment, the first capacitor 33 is C1. The first power supply 31 is an integrated AC / DC converter with multi-channel protection, designed specifically for the overall power supply needs of the insulation resistance monitoring device. The first power supply 31 includes a first terminal VCC, a second terminal VDD, and a third terminal VPP. The first terminal VCC is a 3.3VDC low-voltage power supply output terminal, providing a stable operating power supply for the control module 2, transceiver, and other low-voltage signal processing units, meeting the low-voltage and high-precision power supply requirements of the low-voltage modules. The second terminal VDD is a 24VDC medium-voltage power supply output terminal, providing operating power for the execution module 5, analog leakage current monitoring circuit 4, and other execution units, matching the voltage drive requirements of high-voltage execution components. The third terminal VPP of the first power supply 31 is a dedicated output terminal for the detection voltage, serving as the core power supply terminal for the leakage current detection circuit. It outputs a constant DC detection voltage, and its output terminal integrates current limiting protection to prevent power supply damage caused by short circuits in the detection circuit.

[0047] The first power supply 31 is used to output the detection voltage. The positive terminal of the first power supply 31 is connected to the main grounding terminal, and the negative terminal of the first power supply 31 is grounded.

[0048] In this embodiment, the detection voltage is a constant 60VDC voltage, output separately from the third terminal vpp of the first power supply 31. This voltage value is precisely matched to the insulation monitoring requirements of power lines with multiple voltage levels from 300VAC to 3300VAC. This ensures that a real-time leakage current at the microampere level is generated in the leakage detection circuit, which is precisely negatively correlated with the equivalent insulation resistance of the line, thus ensuring that the signal can be accurately acquired and calculated. At the same time, it is within the safe low-voltage range, avoiding secondary insulation faults in the monitored power lines caused by excessively high detection voltage. Furthermore, the constant output characteristic of 60VDC eliminates the interference of voltage fluctuations on the insulation resistance calculation results, ensuring monitoring accuracy.

[0049] The three-phase reactor 32 is connected to the power line to be monitored and the first capacitor 33 respectively, and is connected to the main grounding electrode through the first capacitor 33.

[0050] In this embodiment, the three-phase reactor 32 is a dedicated three-phase three-wire dry-type reactor, configured with three independent winding terminals and a common bus terminal. The three winding terminals are electrically connected to phases A, B, and C of the power line to be monitored, respectively. The common bus terminal is directly rigidly connected to one end of the first capacitor 33, and the other end of the first capacitor 33 is reliably electrically connected to the main grounding electrode. The winding impedance of the three-phase reactor 32 is customized and matched to effectively suppress interference signals generated by grid harmonics, zero-sequence voltage, and load fluctuations in the power line to be monitored, preventing interference signals from entering the leakage current detection circuit and affecting the accuracy of real-time leakage current acquisition. Simultaneously, the three-phase reactor 32 and the first capacitor 33 cooperate to form a high-resistance grounding structure, replacing the direct grounding method. This provides a stable and continuous flow path for the real-time leakage current, limits the maximum current in the detection circuit, avoids short circuits causing damage to the core components of the device, and ensures the consistency and synchronization of the three-phase insulation status monitoring of the power line to be monitored.

[0051] The connection point between the three-phase reactor 32 and the first capacitor 33 is connected to the signal processing module 1.

[0052] In this embodiment of the application, the connection point is the real-time leakage current acquisition end, which is directly connected to the filtering unit 12 of the signal processing module 1 to realize lossless and delayless transmission of real-time leakage current.

[0053] In this embodiment, the first power supply 31 provides a stable DC detection voltage for the leakage current detection circuit, ensuring the continuous operation of the detection work. The three-phase reactor 32 is adapted to the monitoring requirements of the three-phase power line, while effectively suppressing harmonic interference in the power grid and improving the stability of the detection circuit. The first capacitor 33 and the three-phase reactor 32 work together to form a high-resistance ground, providing a reliable path for the real-time leakage current and avoiding the short-circuit risk caused by direct grounding. The overall structure can stably construct a leakage current detection circuit that matches the power line to be monitored, accurately collect the real-time leakage current, and provide high-quality hardware support for subsequent signal processing and insulation status determination.

[0054] In one alternative embodiment, the insulation resistance monitoring device further includes an analog leakage current monitoring circuit 4 connected to the signal processing module 1.

[0055] Control module 2 is also used to determine the simulated leakage current based on the target insulation resistance threshold, and generate a first control command based on the simulated leakage current. The first control command is then sent to the simulated leakage monitoring circuit 4.

[0056] The analog leakage current monitoring circuit 4 is used to generate an analog leakage current according to the first control command and output it to the signal processing module 1.

[0057] In this embodiment, the simulated leakage current monitoring circuit 4, together with the signal processing module 1, the three-phase reactor 32, and the first capacitor 33, forms a simulated leakage current monitoring loop. This simulated leakage current monitoring loop reuses the hardware components of the three-phase reactor 32 and the first capacitor 33 of the insulation monitoring circuit 3, and is completely consistent with the hardware transmission path of the actual leakage current detection loop. This ensures that the simulated leakage current detection scenario closely matches the real monitoring scenario, guaranteeing the reference value and accuracy of the self-test results.

[0058] Signal processing module 1 is also used to determine the analog voltage corresponding to the analog leakage current. The analog voltage is then output to control module 2.

[0059] In this embodiment, the processing flow of the analog leakage current by the signal processing module 1 is exactly the same as that of the real-time leakage current. Referring to the process of determining the real-time voltage corresponding to the real-time leakage current described above, it will not be described in detail here.

[0060] Control module 2 is also used to determine whether the insulation resistance monitoring device is faulty based on the analog voltage.

[0061] In this embodiment, the control module 2 may have a pre-set theoretical simulated voltage threshold range corresponding to the simulated leakage current. The control module 2 compares the received simulated voltage with the preset theoretical simulated voltage threshold range. If the simulated voltage is within the threshold range, the insulation resistance monitoring device is determined to be working normally and without fault. If the simulated voltage is not within the threshold range, the insulation resistance monitoring device is determined to be faulty. The control module 2 can also generate a fault code when it determines that the insulation resistance monitoring device is faulty and feed it back to the background monitoring system. As an example, the control module 2 can also determine the corresponding insulation resistance based on the simulated voltage, and determine that the insulation resistance monitoring device is faulty when the difference between the insulation resistance and the corresponding target insulation resistance threshold is greater than a preset threshold.

[0062] In this embodiment, the simulated leakage current monitoring circuit 4 specifically includes: a second power supply 41 and a test button 42. The test button 42 is AN.

[0063] The second power supply 41 is a controllable constant current source. Its input terminal is connected to the second terminal (Vdd) of the first power supply 31, using a stable 24VDC voltage as its operating power supply. The control terminal of the second power supply 41 is electrically connected to the digital-to-analog converter (DAC) pin of the control module 2 to receive the first control command sent by the control module 2. Its output terminal is electrically connected to one end of the test button 42. This controllable constant current source can precisely adjust the magnitude of the output simulated leakage current according to the first control command. The output current accuracy error is ≤±0.5%, and the output current range matches the simulated leakage current range corresponding to the full voltage level of 300VAC-3300VAC. It can stably generate a simulated leakage current corresponding to the target insulation resistance threshold and has overcurrent protection characteristics to prevent excessive output current from damaging circuit components. The test button 42 is a self-resetting normally open mechanical button, serving as a manual on / off control element for the simulated leakage current monitoring circuit. One end of the test button 42 is electrically connected to the output terminal of the second power supply 41 (controllable constant current source), and the other end is connected to the filter unit 12 of the signal processing module 1. Normally, it is in the open state, and the simulated leakage current monitoring circuit is open. Pressing the test button 42 closes the circuit, and the simulated leakage current is output to the signal processing module 1 through the button. Releasing the button automatically resets it to the open state, and the circuit returns to open. This test button 42 supports both manual triggering of the device's self-test process and can be used in conjunction with the automatic control logic of the control module 2 to achieve timed self-testing, balancing operational flexibility with the device's intelligent self-testing requirements.

[0064] This embodiment of the application constructs a complete self-test loop by adding a simulated leakage current monitoring circuit 4 connected to the signal processing module 1. By generating a simulated leakage current that matches the actual monitoring scenario, the effectiveness of each module of the insulation resistance monitoring device is verified in reverse. This allows for timely detection of device faults, avoiding inaccurate monitoring and protection failures caused by device malfunctions. At the same time, the simulated leakage current matches the target insulation resistance threshold, making the self-test process conform to the monitoring requirements of different voltage levels, improving the accuracy of the self-test results, and ensuring the stability and reliability of the overall monitoring function of the device.

[0065] In one alternative implementation, the insulation resistance monitoring device further includes an execution module 5 connected to the control module 2.

[0066] The control module 2 is also used to generate a high-level signal and send the high-level signal to the execution module 5 when there is an abnormality in the insulation status of the power line to be monitored.

[0067] Execution module 5 is used to disconnect the power line to be monitored when a high-level signal is received.

[0068] In this embodiment of the application, an execution module 5 connected to the control module 2 is added. When the control module 2 determines that the insulation state of the power line to be monitored is abnormal, it generates and sends a high-level signal to the execution module 5. After receiving the high-level signal, the execution module 5 immediately disconnects the power line to be monitored.

[0069] In one optional implementation, execution module 5 includes: The circuit includes a switch 51, a relay 52, and a circuit breaker 53. The circuit breaker 53 is installed on the power line to be monitored. The relay 52 includes a coil, a first normally open contact 521, and a second normally open contact 522. The switch 51 is T4, the relay 52 is K1, and the circuit breaker 53 is Q1. The first normally open contact 521 is K1-1, and the second normally open contact 522 is K1-2.

[0070] In this embodiment, the execution module 5 further includes a first resistor 54 and a first diode 55. The first resistor 54 is a current-limiting protection resistor, and the first diode 55 is a freewheeling protection diode. Together, they provide hardware protection for the switching transistor 51 and the relay coil 52, preventing damage to the components due to overcurrent and reverse electromotive force, and improving the overall stability and service life of the execution module 5.

[0071] The base of the switching transistor 51 is connected to the control module 2, and the collector of the switching transistor 51 is connected to the coil of the relay 52 and the first normally open contact 521, respectively.

[0072] In this embodiment, the switching transistor 51 is an NPN transistor. Its base is electrically connected to the I / O output pin of the control module 2 through a first resistor 54. The first resistor 54 is connected in series in the base circuit, which can limit the current flowing into the base of the switching transistor 51, preventing the high-level signal output by the control module 2 from generating excessive base current and burning out the switching transistor 51, thus achieving current limiting protection. The emitter of the switching transistor 51 is directly grounded, and the collector is electrically connected to one end of the coil of the relay 52 and one end of the first normally open contact 521 of the relay 52. ​​The other end of the coil of the relay 52 is electrically connected to the second terminal Vdd (24VDC) of the first power supply 31, forming a complete power supply circuit for the coil of the relay 52.

[0073] The second normally open contact 522 of relay 52 is connected in series with circuit breaker 53.

[0074] In this embodiment, the second normally open contact 522 of the relay 52 is the trip trigger terminal of the circuit breaker 53. One end of the relay 52 is electrically connected to the trip control pin of the circuit breaker 53, and the other end is electrically connected to the second terminal Vdd (24VDC) of the first power supply 31. The circuit breaker 53 is connected in series in the three-phase main circuit of the power line to be monitored and serves as the main on / off switch of the power line to be monitored. It is adapted to the current switching requirements of multiple voltage levels from 300VAC to 3300VAC and has the characteristics of sensitive tripping action and stable closing action. Its tripping action is triggered by the closing of the second normally open contact 522. When there is no trigger signal, it remains in the closed conducting state.

[0075] The switching transistor 51 is used to turn on when receiving a high-level signal from the control module 2, so that the coil of the relay 52 is energized, causing the first normally open contact 521 and the second normally open contact 522 to close, the circuit breaker 53 to open, and the power line to be monitored to be disconnected.

[0076] In this embodiment, the first diode 55 is connected in reverse parallel across the coil of the relay 52. ​​Its anode is electrically connected to the collector of the switching transistor 51, and its cathode is electrically connected to the second terminal Vdd (24VDC) of the first power supply 31. When the switching transistor 51 is turned on, the coil of the relay 52 is energized, generating an electromagnetic attraction that causes the first normally open contact 521 and the second normally open contact 522 to close synchronously. The closing of the second normally open contact 522 triggers the circuit breaker 53 to trip, disconnecting the monitored power line. After the first normally open contact 521 closes, it forms a self-locking circuit with the coil of the relay 52 and the first power supply 31 Vdd, ensuring that the coil remains energized and the contacts remain closed when the state of the switching transistor 51 changes subsequently. When the coil is de-energized, a reverse electromotive force is generated. The first diode 55 can discharge the reverse electromotive force to the ground terminal, preventing the reverse electromotive force from breaking down the switching transistor 51 and achieving freewheeling protection. After receiving the 3.3V high-level signal output by the control module 2, the base of the switching transistor 51 receives a forward bias current, and the collector and emitter quickly conduct, energizing the coil of the relay 52 and completing the trigger action to disconnect the entire fault circuit. The entire action response delay is ≤10ms, ensuring the timeliness of the protection action.

[0077] This embodiment of the application achieves precise linkage between electrical signals and mechanical actions by implementing the execution module 5. The switching tube 51 can quickly respond to the high-level signal of the control module 2, ensuring the timeliness of the protection action. The normally open contact design of the relay 52 realizes self-locking after the coil is energized, ensuring that the circuit breaker 53 stably disconnects the faulty line. The circuit breaker 53 is directly installed on the power line to be monitored, and can reliably cut off the line current. The overall structure has clear logic and precise coordination, improving the stability, timeliness and reliability of the fault line disconnection operation.

[0078] In an optional implementation, the execution module 5 further includes a reset button 56.

[0079] The control module 2 is also used to generate a reset signal and send the reset signal to the reset button 56 when the insulation status of the power line to be monitored returns to normal.

[0080] In this embodiment, the reset signal is an electrically triggered signal output by the control module 2, adapted to the 24VDC operating voltage of the first power supply 31, and sent from the dedicated I / O pin of the control module 2 to the electromagnetic control terminal of the reset button 56. The reset button 56 is connected in series at the common node of the coil power supply main circuit and the self-locking circuit of the relay 52, and is the core on / off control element of the entire circuit. The control module 2 only generates and sends the reset signal after detecting that the real-time insulation resistance is continuously greater than the target insulation resistance threshold and determining that the insulation state has been completely restored to normal, so as to avoid accidental reset operation when the fault has not been cleared.

[0081] The reset button 56 is used to disconnect when a reset signal is received from the control module 2, so that the coil of the relay 52 is de-energized, the first normally open contact 521 and the second normally open contact 522 are disconnected, the circuit breaker 53 is closed, and the power line to be monitored is connected.

[0082] In this embodiment, the reset button 56 is an electromagnetic automatic reset normally open / normally closed switch button. Normally, it remains mechanically closed, providing a continuous conduction path for the power supply circuit and self-locking circuit of the relay 52 coil. It features dual control modes: electromagnetic trigger disconnection and manual press disconnection. The electromagnetic control terminal is connected to the control module 2. Upon receiving a reset signal, the internal electromagnetic mechanism drives the button contacts to open. The button also has a physical press terminal, supporting manual trigger disconnection by maintenance personnel on-site, adapting to manual reset scenarios after device self-testing and fault repair. When the reset button 56 receives a reset signal and disconnects, the power supply circuit of the relay 52 coil is cut off, the coil immediately loses power, the electromagnetic attraction disappears, and the first normally open contact 521 and the second normally open contact 522 synchronously reset to their initial normally open state. After the first normally open contact 521 opens, the self-locking circuit of the relay 52 fails, and continuous power supply can no longer be established. After the second normally open contact 522 opens, the trip trigger signal of circuit breaker 53 disappears, and circuit breaker 53 automatically resets and closes. The three-phase main circuit of the monitored power line is restored to conduction, and normal power supply is restored. After completing the disconnection action and realizing the line reset, the reset button 56 will automatically return to the mechanical closed state, preparing for the next protection action and reset operation, ensuring the cyclic operation capability of execution module 5.

[0083] In this embodiment, a reset button 56 is added to the execution module 5. When the insulation state of the power line to be monitored returns to normal, the control module 2 generates a reset signal and sends it to the reset button 56. After receiving the signal, the reset button 56 disconnects, causing the coil of the relay 52 to lose power and the normally open contact to open, thereby triggering the circuit breaker 53 to close and restore the line conduction.

[0084] In one optional implementation, the signal processing module 1 includes: Sampling resistor 11, filtering unit 12 and signal amplification unit 13.

[0085] In this embodiment, the filter unit 12, the sampling resistor 11, and the signal amplification unit 13 are modular structures connected in series. Each unit is directly connected to the other without any additional adapters, achieving lossless and delayless transmission of leakage current. Furthermore, the power supply terminals of each unit are adapted to the first power supply 31. The filter unit 12 and the sampling resistor 11 are powered by the third terminal Vpp of the first power supply 31, and the signal amplification unit 13 is powered by the first terminal Vcc (3.3VDC) of the first power supply 31, ensuring stable operating voltage for each unit.

[0086] The filtering unit 12 is connected to the insulation monitoring circuit 3 and is used to filter the real-time leakage current and input the filtered real-time leakage current into the sampling resistor 11.

[0087] In this embodiment, the filtering unit 12 is a dual-T active filter circuit. Its input terminal is directly connected to the connection point of the three-phase reactor 32 and the first capacitor 33 in the insulation monitoring circuit 3. It is specifically designed for power grid leakage detection scenarios and can accurately filter out zero-sequence voltage, power grid harmonics, noise and power frequency interference signals in the real-time leakage current, retaining only the pure DC leakage current that reflects the insulation status of the line. At the same time, it has high input impedance characteristics to avoid shunting the current of the leakage detection circuit. The pure DC leakage current after filtering is directly input to the input terminal of the sampling resistor 11, providing an accurate current source for subsequent electrical signal conversion.

[0088] The sampling resistor 11 is used to convert the received real-time leakage current into the corresponding real-time voltage and output the real-time voltage to the signal amplification unit 13.

[0089] In this embodiment, the sampling resistor 11 is a high-precision, low-temperature-drift precision resistor with a customized matching design to meet the microampere-level real-time leakage current acquisition requirements corresponding to multiple voltage levels from 300VAC to 3300VAC. The resistance value error is ≤±0.1%, and the temperature drift coefficient is ≤5ppm / ℃, effectively avoiding voltage conversion errors caused by resistance changes. Based on Ohm's law U=IR, the sampling resistor 11 achieves linear and precise current-to-voltage conversion, converting the input DC leakage current into a millivolt-level real-time voltage. The voltage across its terminals is directly output to the input terminal of the signal amplification unit 13. The converted real-time voltage is strictly positively correlated with the real-time leakage current, providing a true and accurate voltage basis for subsequent signal amplification and insulation resistance calculation.

[0090] The signal amplification unit 13 is used to amplify the real-time voltage and output the amplified real-time voltage to the control module 2.

[0091] In this embodiment, the signal amplification unit 13 is a high-precision differential operational amplifier circuit. Its non-inverting input is electrically connected to the voltage output of the sampling resistor 11, and its inverting input is configured with an adjustable feedback resistor. This enables precise amplification at a fixed factor, matching the signal acquisition threshold of the ADC pin of the control module 2. This amplifies the weak real-time voltage in the millivolt range to a standard voltage range of 0-3.3V, meeting the electrical signal acquisition requirements of the control module 2. The differential amplification structure effectively suppresses common-mode interference, further improving the signal-to-noise ratio and purity of the voltage. Simultaneously, the amplification circuit possesses low offset and low drift characteristics, avoiding the introduction of additional errors during amplification. The amplified standard real-time voltage is directly output to the ADC acquisition pin of the control module 2 via a signal transmission line, providing a high-quality electrical signal input for the control module 2 to calculate the real-time insulation resistance.

[0092] This application innovatively addresses the needs for multi-voltage level adaptation and related technical deficiencies. Through a hardware and software collaborative architecture design of insulation monitoring circuit, signal processing module, and control module, it achieves full-process control of multi-voltage level adaptation, real-time insulation resistance monitoring, simulated leakage self-test, and active protection. Compared with the traditional solution of fixed load resistor combined with current acquisition, the technical effect is significantly improved.

[0093] Abandoning the traditional fixed load resistor design, the insulation resistance thresholds corresponding to different voltage levels are pre-set in the control module. No on-site hardware adjustments are required; the insulation monitoring needs of the energy storage PCS grid at voltage levels of 380VAC-1140VAC and subsequent upgrades can be matched solely through software configuration. This solves the problems of poor adaptability and cumbersome operation of traditional solutions, significantly reducing the hardware cost and maintenance workload of grid upgrades and transformations, and perfectly compatibility with the expansion needs of multi-voltage grids.

[0094] By forming a leakage current detection loop with the monitored power grid and the main grounding electrode through an insulation monitoring circuit, the real-time leakage current of the power grid is accurately collected. After filtering, conversion, and amplification by the signal processing module, the signal is output to the control module, which calculates the real-time insulation resistance of the power grid system. This enables continuous and accurate monitoring of the power grid's insulation resistance. It overcomes the limitations of traditional solutions that only provide passive protection after the leakage current reaches a set value. By observing the real-time trend of insulation resistance changes, it can predict the risk of leakage current, short circuits, and other faults in advance, transforming post-event protection into pre-event warning, thus reducing the probability of safety accidents at their source.

[0095] The system is equipped with a simulated leakage current monitoring circuit and a controllable constant current source. Based on the insulation resistance requirements corresponding to the current voltage level of the power grid, it can accurately configure and output the corresponding self-test current (simulated leakage current). This constructs a simulated leakage current monitoring loop that closely matches the actual monitoring scenario, reusing the hardware components of the actual leakage current detection loop to ensure consistency between the self-test scenario and the real monitoring scenario. The control module analyzes the simulated voltage during the self-test process to quickly determine the operational effectiveness of each module, promptly identifying faults in the monitoring loop, signal processing, and control unit. This prevents inaccurate monitoring and protection failures caused by device malfunctions, ensuring continuous, stable, and reliable insulation monitoring.

[0096] The insulation resistance threshold can be flexibly set and updated through the control module, supporting dynamic adjustment of the insulation resistance threshold corresponding to different voltage levels based on power grid operating conditions and safety protection requirements, thus offering greater adaptability. The control module intelligently compares the real-time calculated power grid insulation resistance value with the target insulation resistance threshold for the corresponding voltage level, accurately determining whether the power grid insulation status is abnormal. This avoids the protection misjudgment and missed judgment problems caused by power grid changes in traditional fixed threshold schemes, significantly improving the accuracy and specificity of insulation protection judgment.

[0097] When the control module detects an abnormality in the power grid insulation, it immediately generates a high-level signal to trigger the execution module, quickly disconnecting the faulty line for active protection. After detecting that the power grid insulation has returned to normal, a reset signal triggers the execution module to complete an intelligent reset, restoring normal power supply to the grid. The entire process requires no manual intervention, featuring fast response and precise protection. Compared to traditional passive protection schemes, this significantly improves the timeliness and intelligence of power grid insulation protection, comprehensively ensuring the stable and safe operation of the power grid.

[0098] Figure 3 This is a flowchart illustrating the insulation resistance monitoring method according to an embodiment of this application. It should be noted that the steps shown in the flowchart can be executed in a computer system such as a set of computer-executable instructions. Also, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0099] like Figure 3 As shown, this application provides an insulation resistance monitoring method, which is applied to the insulation resistance monitoring device of the above embodiments or any corresponding implementation thereof. The insulation resistance monitoring method includes: S101: Obtain the real-time leakage current in the leakage detection circuit.

[0100] S102: Determine the real-time voltage corresponding to the real-time leakage current.

[0101] S103: Determine the real-time insulation resistance of the power line to be monitored based on the real-time voltage.

[0102] S104: Determine whether there is any abnormality in the insulation status of the power line to be monitored based on the real-time insulation resistance and the target insulation resistance threshold.

[0103] In this embodiment of the application, the target insulation resistance threshold is the insulation resistance threshold corresponding to the voltage level of the power line to be monitored.

[0104] In one optional implementation, the insulation resistance monitoring method further includes: The simulated leakage current is determined based on the target insulation resistance threshold.

[0105] Determine the analog voltage corresponding to the simulated leakage current.

[0106] Determine if the insulation resistance monitoring device is faulty based on the simulated voltage.

[0107] This application also provides a computer-readable storage medium storing computer instructions that are used to cause a computer to perform the steps in the above method embodiments.

[0108] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this application.

Claims

1. An insulation resistance monitoring device, characterized in that, include: A signal processing module, a control module, and an insulation monitoring circuit connected to the signal processing module; The control module is pre-set with insulation resistance thresholds corresponding to different voltage levels; The insulation monitoring circuit is used to form a leakage current detection loop with the power line to be monitored and the main grounding electrode, and output the real-time leakage current in the leakage current detection loop to the signal processing module. The signal processing module is used to determine the real-time voltage corresponding to the real-time leakage current and output the real-time voltage to the control module. The control module is used to determine the real-time insulation resistance of the power line to be monitored based on the real-time voltage; and to determine whether there is an abnormality in the insulation status of the power line to be monitored based on the real-time insulation resistance and the target insulation resistance threshold. The target insulation resistance threshold is the insulation resistance threshold corresponding to the voltage level of the power line to be monitored.

2. The insulation resistance monitoring device according to claim 1, characterized in that, The device further includes: an analog leakage current monitoring circuit connected to the signal processing module; The control module is further configured to determine the simulated leakage current based on the target insulation resistance threshold, generate a first control command based on the simulated leakage current, and send the first control command to the simulated leakage monitoring circuit. The simulated leakage current monitoring circuit is used to generate the simulated leakage current according to the first control command and output it to the signal processing module; The signal processing module is further configured to determine the analog voltage corresponding to the analog leakage current and output the analog voltage to the control module. The control module is also used to determine whether the insulation resistance monitoring device is faulty based on the analog voltage.

3. The insulation resistance monitoring device according to claim 1, characterized in that, The device further includes an execution module connected to the control module; The control module is also used to generate a high-level signal and send the high-level signal to the execution module when there is an abnormality in the insulation state of the power line to be monitored; The execution module is used to disconnect the power line to be monitored when it receives the high-level signal.

4. The insulation resistance monitoring device according to claim 3, characterized in that, The execution module includes: The device includes a switching transistor, a relay, and a circuit breaker; the circuit breaker is installed on the power line to be monitored; the relay includes a coil, a first normally open contact, and a second normally open contact. The base of the switching transistor is connected to the control module, and the collector of the switching transistor is connected to the coil of the relay and the first normally open contact, respectively. The second normally open contact of the relay is connected in series with the circuit breaker; The switching transistor is used to conduct when it receives a high-level signal from the control module, thereby energizing the coil of the relay, causing the first normally open contact and the second normally open contact to close, the circuit breaker to open, and the power line to be monitored to disconnect.

5. The insulation resistance monitoring device according to claim 4, characterized in that, The execution module further includes a reset button; The control module is also used to generate a reset signal and send the reset signal to the reset button when the insulation state of the power line to be monitored returns to normal. The reset button is used to disconnect when a reset signal is received from the control module, thereby de-energizing the relay coil, causing the first normally open contact and the second normally open contact to open, closing the circuit breaker, and enabling the monitored power line to conduct.

6. The insulation resistance monitoring device according to claim 1, characterized in that, The signal processing module includes: Sampling resistor, filtering unit, and signal amplification unit; The filtering unit is connected to the insulation monitoring circuit and is used to filter the real-time leakage current and input the filtered real-time leakage current into the sampling resistor. The sampling resistor is used to convert the received real-time leakage current into a corresponding real-time voltage and output the real-time voltage to the signal amplification unit; The signal amplification unit is used to amplify the real-time voltage and output the amplified real-time voltage to the control module.

7. The insulation resistance monitoring device according to claim 1, characterized in that, The insulation monitoring circuit includes: First power supply, three-phase reactor and first capacitor; The first power supply is used to output the detection voltage. The positive terminal of the first power supply is connected to the main grounding terminal, and the negative terminal of the first power supply is grounded. The three-phase reactor is connected to the power line to be monitored and the first capacitor respectively, and is connected to the main grounding electrode through the first capacitor; The connection point between the three-phase reactor and the first capacitor is connected to the signal processing module.

8. An insulation resistance monitoring method, applied to the insulation resistance monitoring device according to any one of claims 1 to 7, characterized in that, include: Obtain the real-time leakage current in the leakage detection circuit; Determine the real-time voltage corresponding to the real-time leakage current; The real-time insulation resistance of the power line to be monitored is determined based on the real-time voltage. The insulation status of the power line to be monitored is determined based on the real-time insulation resistance and the target insulation resistance threshold. The target insulation resistance threshold is the insulation resistance threshold corresponding to the voltage level of the power line to be monitored.

9. The insulation resistance monitoring method according to claim 8, characterized in that, The method further includes: The simulated leakage current is determined based on the target insulation resistance threshold. Determine the analog voltage corresponding to the simulated leakage current; The presence of a fault in the insulation resistance monitoring device is determined based on the simulated voltage.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the method of any one of claims 8 or 9.

Images