High-voltage isolated ground wire status detection system, method and electronic equipment

Abstract

The present invention provides a high-voltage isolated ground wire status detection system, method, and electronic device, relating to the technical field of high-voltage, high-power electronic power supply energy conversion, comprising: a ground wire status detection terminal and a frequency acquisition terminal; wherein the ground wire status detection terminal is used to convert the capacitance change between the neutral wire and the protective ground wire into a resonant frequency change; the frequency acquisition terminal is used to acquire the resonant frequency change, and determine the capacitance change state between the neutral wire and the protective ground wire based on the resonant frequency change, as well as the ground wire contact state corresponding to the current capacitance state, wherein the ground wire contact state includes: ground wire connected, ground wire disconnected, and poor ground wire contact. The present invention can significantly improve the safety and accuracy of ground wire status detection.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage and high-power electronic power supply energy conversion, and in particular to a high-voltage isolated ground wire state detection system, method and electronic equipment. Background Art

[0002] Accurately detecting the ground connection status of the power generation and consumption sides of high-voltage grounding equipment can effectively avoid safety accidents caused by N-PE problems. Currently, related technologies propose that power can be directly or indirectly taken from the AC power supply as the positive pole of the power supply, and the safety ground wire can be used as the negative pole of the power supply, so as to use the voltage sampling method to sample whether the safety ground is connected: if it is connected, a certain voltage difference will be formed on the sampling resistor, and the voltage difference can be used to determine whether the safety ground wire is connected. However, when the AC voltage drops, the circuit is prone to malfunction. When the AC voltage drops to a certain voltage threshold, the circuit will fail. Moreover, this solution cannot accurately feedback the change of the safety ground wire contact point resistance in real time, which poses a safety hazard. In addition, the instability of the grid voltage is also prone to malfunction. Summary of the Invention

[0003] In view of this, an object of the present invention is to provide a high-voltage isolated ground wire status detection system, method and electronic equipment, which can significantly improve the safety and accuracy of ground wire status detection.

[0004] In a first aspect, an embodiment of the present invention provides a high-voltage isolated ground wire status detection system, the system comprising: a ground wire status detection terminal and a frequency acquisition terminal; wherein the ground wire status detection terminal is used to convert the capacitance change between the neutral wire and the protective ground wire into a resonant frequency change; the frequency acquisition terminal is used to acquire the resonant frequency change, and determine the capacitance change state between the neutral wire and the protective ground wire according to the resonant frequency change, as well as the ground wire contact state corresponding to the current capacitance state, wherein the ground wire contact state includes: ground wire connection, ground wire disconnection and poor ground wire contact.

[0005] In one embodiment, the frequency acquisition terminal includes: a frequency acquisition network; wherein the frequency acquisition network is used to acquire a frequency signal of a resonant frequency.

[0006] In one embodiment, the frequency acquisition network includes: a first resistor and a second resistor; wherein the first resistor and the second resistor are used to convert the frequency signal into a voltage signal or a current signal for signal acquisition processing.

[0007] In one embodiment, the frequency acquisition terminal further includes: a signal excitation circuit; wherein the signal excitation circuit is used to provide an excitation signal and an excitation source within a preset frequency range.

[0008] In one embodiment, the signal excitation circuit includes: a third resistor, a fourth resistor, a fifth resistor, a switching transistor, a diode and a first capacitor; wherein the fifth resistor is connected to the cathode of the diode in parallel with the first capacitor, the first pin of the switching transistor is connected to the third resistor and the fourth resistor, the second pin of the switching transistor is connected to the anode of the diode, and the third pin of the switching transistor is connected to the signal ground.

[0009] In one embodiment, the ground state detection terminal includes an LC resonant circuit, wherein the LC resonant circuit includes a second capacitor and a transformer.

[0010] In one embodiment, the ground wire status detection terminal further includes: a live wire and a neutral wire; wherein, between the neutral wire and the ground wire are: a third capacitor and a fourth capacitor, and between the live wire and the neutral wire is: a fifth capacitor.

[0011] In the second aspect, an embodiment of the present invention also provides a high-voltage isolated ground wire status detection method, which is applied to a high-voltage isolated ground wire status detection system. The method includes: through the principle of capacitance resonance, converting the capacitance change between the neutral wire and the protective ground wire when the ground wire is connected, disconnected, and the ground wire has poor contact into a resonant frequency change; determining the current ground wire contact status based on the resonant frequency change.

[0012] In one embodiment, when the ground wire is connected, the fourth capacitor and the fifth capacitor are connected in series and then in parallel with the third capacitor, and the third capacitor is short-circuited. The step of converting the capacitance change between the neutral wire and the protective ground wire when the ground wire is connected into a resonant frequency change includes: using a transformer and a second capacitor to determine the resonant frequency.

[0013] In one embodiment, when the ground wire is disconnected, the second capacitor, the third capacitor, the fourth capacitor, the fifth capacitor, and the transformer form a loop, and the step of converting the capacitance change between the neutral wire and the protective ground wire when the ground wire is disconnected into a resonant frequency change includes: using the transformer, the second capacitor, and the capacitance parameters of the neutral wire and the live wire to ground to determine the resonant frequency.

[0014] In a third aspect, an embodiment of the present invention further provides an electronic device comprising a processor and a memory, wherein the memory stores computer-executable instructions that can be executed by the processor, and the processor executes the computer-executable instructions to implement any one of the methods provided in the second aspect.

[0015] The embodiments of the present invention bring the following beneficial effects:

[0016] A high-voltage isolated ground wire status detection system, method, and electronic device provided by an embodiment of the present invention can convert the capacitance change between the neutral wire and the protective ground wire into a resonant frequency change through a ground wire status detection end, collect the resonant frequency change through a frequency acquisition end, and determine the capacitance change state between the neutral wire and the protective ground wire, as well as the ground wire contact state corresponding to the current capacitance state, based on the resonant frequency change. The embodiment of the present invention can adopt the principle of capacitance resonance to convert the capacitance change into a frequency change to improve the sampling accuracy, thereby significantly improving the safety and accuracy of ground wire status detection.

[0017] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or understood by practicing the present invention. The purposes and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0018] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 A schematic structural diagram of a high-voltage isolated ground wire status detection system provided by an embodiment of the present invention;

[0021] Figure 2 A schematic diagram of the specific structure of a high-voltage isolated ground wire status detection system provided by an embodiment of the present invention;

[0022] Figure 3 A schematic flow chart of a high-voltage isolated ground wire status detection method provided by an embodiment of the present invention;

[0023] Figure 4 A schematic diagram of a ground wire connection equivalent circuit provided by an embodiment of the present invention;

[0024] Figure 5 A schematic diagram of a ground wire disconnection equivalent circuit provided by an embodiment of the present invention;

[0025] Figure 6 A schematic diagram of an equivalent circuit for poor ground contact provided by an embodiment of the present invention;

[0026] Figure 7 A schematic structural diagram of an electronic device provided by an embodiment of the present invention.

[0027] Among them, D-diode; T-transformer; Q-switching transistor; R1-first resistor; R2-second resistor; R3-third resistor; R4-fourth resistor; R5-fifth resistor; C1-first capacitor; C2-second capacitor; C3-third capacitor; C4-fourth capacitor; C5-fifth capacitor. DETAILED DESCRIPTION

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0029] Currently, the neutral wire and the ground wire are usually connected on the generator side of the high-voltage grounding wire equipment. If the ground wires on the generator side and the power consumption side are connected, the neutral wire and the ground wire on the power consumption side are also connected. If the ground wires on the generator side and the power consumption side are disconnected, the neutral wire and the ground wire on the power consumption side are disconnected. Accurately detecting the ground wire connectivity status on the generator side and the power consumption side of the high-voltage grounding wire equipment can effectively avoid safety accidents caused by N-PE problems. Related technologies propose that power can be directly or indirectly taken from the AC power as the positive pole of the power supply, and the safety ground wire can be used as the negative pole of the power supply, so as to use the voltage sampling method to sample whether the safety ground is connected: if it is connected, a certain voltage difference will be formed on the sampling resistor. The voltage difference can be used to determine whether the safety ground wire is connected. However, when the AC voltage decreases, the circuit is prone to malfunction. When the AC voltage drops to a certain voltage threshold, the circuit will fail. Moreover, this solution cannot provide real-time and accurate feedback on the change in the resistance of the safety ground wire contact point, which poses a safety hazard. In addition, unstable grid voltage can also easily cause malfunction.

[0030] Specifically, current ground presence detection basically draws power from the L line, drives an optocoupler or transistor after passing through a current-limiting resistor, and when PE is grounded, a path is formed between PE and N, causing the optocoupler or transistor to turn on. The change in the output state of the optocoupler or transistor is then used to determine whether the ground is connected. However, the above solution has the following limitations: when the input voltage is lower than a certain voltage, the current flowing through the optocoupler and transistor decreases, causing the optocoupler or transistor to turn off, resulting in circuit misjudgment and malfunction; when the voltage is too high, due to the connection between PE and N, the current flowing through L and N will form a current difference, which will be detected by the leakage current detection circuit, resulting in malfunction. In actual applications, when PE and N are connected, there is a current loop that is unilaterally rectified through L and N. This return will have a certain negative impact on EMI and affect the stability of the circuit.

[0031] Based on this, the high-voltage isolated ground wire status detection system, method and electronic equipment provided by the present invention can be isolated from the high-voltage circuit, improve the safety of the system, and adopt the capacitance principle to effectively solve the problem of dynamic changes of the ground wire, fundamentally solve the problem of detecting the safe ground wire, and effectively improve the reliability of the system. In addition, the present invention also adopts the capacitance resonance principle to convert the change of capacitance into the change of frequency, which greatly improves the sampling accuracy. Due to the greatly improved sampling accuracy, the changes in the ground wire contact state can be accurately measured, and an accurate prediction can be provided for the changes in the ground wire during use, and accurate maintenance warnings can be provided to maintenance personnel in a timely manner to avoid the occurrence of safety accidents.

[0032] To facilitate understanding of this embodiment, a high-voltage isolated ground wire state detection method disclosed in an embodiment of the present invention is first described in detail. The method is applied to a high-voltage isolated ground wire state detection system. To facilitate understanding of the high-voltage isolated ground wire state detection system, an embodiment of the present invention provides a structural schematic diagram of a high-voltage isolated ground wire state detection system, as shown in FIG. Figure 1 The system shown includes: a ground wire status detection terminal and a frequency acquisition terminal; wherein the ground wire status detection terminal is used to convert the capacitance change between the neutral wire and the protective ground wire into a resonant frequency change; the frequency acquisition terminal is used to acquire the resonant frequency change, and determine the capacitance change state between the neutral wire and the protective ground wire, as well as the ground wire contact state corresponding to the current capacitance state based on the resonant frequency change, wherein the ground wire contact state includes: ground wire connected, ground wire disconnected, and poor ground wire contact.

[0033] See also Figure 2A specific structural diagram of a high-voltage isolated ground wire status detection system is shown. The frequency acquisition end includes: a frequency acquisition network and a signal excitation circuit. The frequency acquisition network is used to collect frequency signals of the resonant frequency. The signal excitation circuit is used to provide an excitation signal and excitation source in a preset frequency range. The ground wire status detection end includes: an LC resonant circuit, a neutral wire and a live wire. The LC resonant circuit includes: a second capacitor and a transformer. A third capacitor and a fourth capacitor are included between the neutral wire and the ground wire. A fifth capacitor is included between the live wire and the neutral wire.

[0034] Specifically, Figure 2 C2, T, R1, R2, R3, R4, Q, D, R5, and C1 form a new ground state detection circuit, wherein the secondary leakage inductance of C2 and T forms an LC resonant circuit, and the frequency acquisition network includes: a first resistor R1 and a second resistor R2, and the first resistor and the second resistor are used to convert the frequency signal into a voltage signal or a current signal for signal acquisition and processing. The signal excitation circuit includes: a third resistor R3, a fourth resistor R4, a fifth resistor R5, a switching transistor Q, a diode D, and a first capacitor C1, wherein the fifth resistor is connected to the cathode of the diode in parallel with the first capacitor, the first pin of the switching transistor is connected to the third resistor and the fourth resistor, the second pin of the switching transistor is connected to the anode of the diode, and the third pin of the switching transistor is connected to the signal ground. The signal excitation circuit can provide an excitation signal and an excitation source within a certain frequency range, wherein CTL-F is a frequency signal.

[0035] Based on the above structure, when grounded, PE and N are connected, C3 is equivalent to a short circuit, and the resonant frequency is determined by C2 and T. When PE and N are disconnected, the frequency is determined by the capacitance parameters of C2, T and N, L to ground. In practical applications, the frequency test can accurately measure whether the grounding is correct, and at the same time, it also completes the isolation of high-voltage signals and weak signals, ensuring the safety of the equipment from the design perspective.

[0036] based on Figure 1 A structural diagram of a high-voltage isolated ground wire status detection system is shown, and Figure 2 The specific structural diagram of a high-voltage isolated ground wire status detection system is shown in FIG. , and the embodiment of the present invention introduces a high-voltage isolated ground wire status detection method in detail. Figure 3 The flowchart of a high-voltage isolated ground wire status detection method shown in FIG. 1 mainly includes the following steps S302 to S304:

[0037] Step S302, through the principle of capacitor resonance, converts the capacitance change between the neutral wire and the protective ground wire when the ground wire is connected, the ground wire is disconnected, and the ground wire has poor contact into a resonant frequency change. In one embodiment, when the ground wire is connected, the fourth capacitor and the fifth capacitor are connected in series and then in parallel with the third capacitor, the third capacitor is short-circuited, and the resonant frequency is determined using the transformer and the second capacitor; when the ground wire is disconnected, the second capacitor, the third capacitor, the fourth capacitor, the fifth capacitor, and the transformer form a loop, and the resonant frequency is determined using the transformer, the second capacitor, and the capacitance parameters of the neutral wire and the live wire to ground; when the ground wire has poor contact, the resonant frequency is determined using the capacitance parameters of the transformer, the second capacitor, the neutral wire and the live wire to ground, and the contact resistance and equivalent inductance when the ground wire has poor contact.

[0038] Step S304 determines the current ground contact status based on the change in resonant frequency. In one embodiment, changes in the N-PE impedance can cause significant changes in the resonant circuit C, which in turn significantly changes the resonant frequency. This frequency change is mapped to the primary side through magnetic coupling in the transformer, allowing easy sampling of the frequency signal FS. This FS frequency signal is independent of the input voltage. Therefore, as long as the auxiliary power supply is functioning properly, the N-PE impedance change can be accurately sampled. This ensures accurate N-PE status detection based on design principles, effectively avoiding safety incidents caused by N-PE problems. Furthermore, changes in N-PE impedance can be detected promptly, providing maintenance personnel with accurate information.

[0039] The above-mentioned high-voltage isolated ground wire status detection method provided by the embodiment of the present invention belongs to the field of high-voltage and high-power power electronic power supply energy conversion, for example, AC power supply, PCS, inverter and other equipment with AC input and output that need to be grounded. It involves the technology of safe and reliable connection of high-voltage ground wires. It is a safer, more reliable and sensitive detection circuit that can significantly improve the safety and accuracy of ground wire status detection.

[0040] With respect to the above step S302, the embodiment of the present invention further provides an implementation method for detecting the resonant frequency under different ground contact states, for details, see (1) to (3) below:

[0041] (1) See Figure 4 The figure shows a schematic diagram of a ground connection equivalent circuit. When grounded, PE and N are connected, C3 is equivalent to a short circuit, and the resonant frequency is determined by C2 and T. Among them, T-L0 is the equivalent inductance of the secondary leakage inductance of T, C2-0 is the capacitance of C2 in different states, and the capacitance of C2 is constant. L1-0 is the equivalent inductance of the loop when the ground wire and N are well grounded.

[0042] (2) See Figure 5Figure 1 shows a schematic diagram of an equivalent circuit with a disconnected ground wire. If PE and N are disconnected, the frequency is determined by the parameters of C2, T, and the N and L capacitances to ground. T-L1 is the equivalent inductance of the secondary leakage inductance of T, C2-1 is the capacitance of C2 in different states (the capacitance of C2 remains constant), L1-1 is the equivalent inductance of the loop when the ground wire and N are disconnected, C5-1 is the equivalent capacitance between L and N, C3-1 is the equivalent capacitance between N and PE, and C4-1 is the equivalent capacitance between L and PE.

[0043] (3) See Figure 6 Figure 2 shows a schematic diagram of an equivalent circuit for poor ground contact. If PE and N have poor contact, the frequency is determined by parameters such as C2, the capacitance between T and N, and L to ground, as well as the contact resistance and equivalent inductance when the ground contact is poor. T-L1 is the equivalent inductance of the secondary leakage inductance of T, C2-1 is the capacitance of C2 in different states (the capacitance of C2 remains constant), L1-1 is the equivalent inductance of the loop when the ground and N are disconnected, C5-2 is the equivalent capacitance between L and N, C3-2 is the equivalent capacitance between N and PE, C4-2 is the equivalent capacitance between L and PE, R0 is the contact resistance between PE and N, and L2-2 is the equivalent inductance when PE and N are in contact.

[0044] To sum up, the present invention can be isolated from the high-voltage circuit, thereby improving the safety of the system, and adopts the capacitor principle to effectively solve the problem of dynamic changes of the grounding wire, fundamentally solving the problem of detecting the safety ground wire, and effectively improving the reliability of the system (no need to draw power from the L line, only a 5V DC voltage from the auxiliary power supply is sufficient); in addition, the present invention also adopts the capacitor resonance principle to convert the change of capacitance into a change of frequency, greatly improving the sampling accuracy. Due to the greatly improved sampling accuracy, the change of the ground wire contact state can be accurately measured, and an accurate prediction can be provided for the change of the ground wire during use, and accurate maintenance warnings can be provided to maintenance personnel in a timely manner to avoid the occurrence of safety accidents.

[0045] The device provided in the embodiment of the present invention has the same implementation principle and technical effects as those in the aforementioned method embodiment. For the sake of brief description, for matters not mentioned in the device embodiment, reference can be made to the corresponding content in the aforementioned method embodiment.

[0046] An embodiment of the present invention provides an electronic device. Specifically, the electronic device includes a processor and a storage device. The storage device stores a computer program, and when the computer program is executed by the processor, it executes the method described in any one of the above-mentioned embodiments.

[0047] Figure 7A structural diagram of an electronic device provided in an embodiment of the present invention, the electronic device 100 includes: a processor 70, a memory 71, a bus 72 and a communication interface 73, wherein the processor 70, the communication interface 73 and the memory 71 are connected via the bus 72; the processor 70 is used to execute an executable module stored in the memory 71, such as a computer program.

[0048] Memory 71 may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage. Communication between the system network element and at least one other network element is achieved through at least one communication interface 73 (which may be wired or wireless), and may utilize the Internet, a wide area network, a local area network, a metropolitan area network, or the like.

[0049] The bus 72 may be an ISA bus, a PCI bus, or an EISA bus. The bus may be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, Figure 7 Only one bidirectional arrow is used in the diagram, but this does not mean that there is only one bus or one type of bus.

[0050] Among them, the memory 71 is used to store programs, and the processor 70 executes the program after receiving the execution instruction. The method executed by the device for flow process definition disclosed in any embodiment of the above-mentioned embodiment of the present invention can be applied to the processor 70 or implemented by the processor 70.

[0051] The processor 70 may be an integrated circuit chip with signal processing capabilities. During implementation, the steps of the above-described method may be performed by hardware integrated logic circuits or software instructions within the processor 70. The processor 70 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It may implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in conjunction with the embodiments of the present invention may be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules within the decoding processor. The software modules may be located in storage media well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or the like. The storage medium is located in the memory 71 , and the processor 70 reads the information in the memory 71 and completes the steps of the above method in combination with its hardware.

[0052] The computer program product of the readable storage medium provided in the embodiment of the present invention includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the method described in the previous method embodiment. The specific implementation can be referred to the previous method embodiment and will not be repeated here.

[0053] If the functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or the portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, electronic device, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage media include various media that can store program code, such as USB flash drives, mobile hard drives, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0054] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-described embodiments within the technical scope disclosed by the present invention, or replace some of the technical features therein with equivalents. Such modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A high-voltage isolated ground wire status detection system, characterized in that: The system includes: a ground state detection terminal and a frequency acquisition terminal; wherein, The ground wire state detection terminal is used to convert the capacitance change between the neutral wire and the protective ground wire into a resonant frequency change; The frequency acquisition terminal is used to collect the resonant frequency change, and determine the capacitance change state between the neutral line and the protective ground line according to the resonant frequency change, and the ground contact state corresponding to the current capacitance state, wherein the ground contact state includes: ground connection, ground disconnection and poor ground contact; The ground state detection terminal includes an LC resonant circuit, wherein the LC resonant circuit includes a second capacitor and a transformer; the ground state detection terminal also includes a live wire and a neutral wire; When the ground wire is connected, the equivalent capacitance between the neutral wire and the ground wire is short-circuited, and the resonant frequency is determined by the capacitance and transformer in the LC resonant circuit. When the ground wire is connected, the equivalent circuit includes: the equivalent inductance of the secondary leakage inductance of the T, the capacitance in the LC resonant circuit, and the equivalent inductance between the neutral wire and the ground wire when the neutral wire and the ground wire are connected. When the ground line is disconnected, the resonant frequency is determined by the capacitance and transformer in the LC resonant circuit, as well as the capacitance parameters of the neutral and live wires to ground. When the ground line is disconnected, the equivalent circuit includes: the equivalent inductance of the T secondary leakage inductance, the capacitance in the LC resonant circuit, the equivalent capacitance between the live wire and the neutral wire, the equivalent capacitance between the neutral wire and ground, the equivalent capacitance between the live wire and ground, and the equivalent inductance between the neutral wire and ground when the neutral wire and ground are disconnected. Among them, when the ground wire contact is poor, the resonant frequency is jointly determined by the capacitance and transformer in the LC resonant circuit, the capacitance parameters of the neutral wire and the live wire to the ground, and the contact resistance and equivalent inductance when the ground wire contact is poor; among them, the equivalent circuit when the ground wire contact is poor includes: the equivalent inductance of the T secondary side leakage inductance, the capacitance in the LC resonant circuit, the equivalent capacitance between the live wire and the neutral wire, the equivalent capacitance between the neutral wire and the ground wire, the equivalent capacitance between the live wire and the ground wire, the contact resistance between the neutral wire and the ground wire, the equivalent inductance between the neutral wire and the ground wire when the neutral wire and the ground wire are disconnected, and the equivalent inductance between the neutral wire and the ground wire when the neutral wire and the ground wire are connected.

2. The high-voltage isolated ground wire status detection system according to claim 1, characterized in that: The frequency acquisition terminal includes: a frequency acquisition network; wherein, The frequency acquisition network is used to acquire a frequency signal of a resonant frequency.

3. The high-voltage isolated ground wire status detection system according to claim 2, characterized in that: The frequency acquisition network includes: a first resistor and a second resistor; wherein, The first resistor and the second resistor are used to convert the frequency signal into a voltage signal or a current signal for signal acquisition and processing.

4. The high-voltage isolated ground wire status detection system according to claim 2, characterized in that: The frequency acquisition end further includes: a signal excitation circuit; wherein, The signal excitation circuit is used to provide an excitation signal and an excitation source within a preset frequency range.

5. The high-voltage isolated ground wire status detection system according to claim 4, characterized in that: The signal excitation circuit includes: a third resistor, a fourth resistor, a fifth resistor, a switching transistor, a diode and a first capacitor; wherein, the fifth resistor is connected to the cathode of the diode after being connected in parallel with the first capacitor, the first pin of the switching transistor is connected to the third resistor and the fourth resistor, the second pin of the switching transistor is connected to the anode of the diode, and the third pin of the switching transistor is connected to the signal ground.

6. A method for detecting the status of a high-voltage isolated ground line, characterized in that: The method is applied to the high-voltage isolated ground wire status detection system according to any one of claims 1 to 5, and the method includes: Through the principle of capacitor resonance, the capacitance change between the neutral wire and the protective ground wire when the ground wire is connected, disconnected, or has poor contact with the ground wire is converted into a change in resonant frequency; The current ground contact state is determined according to the change in the resonant frequency.

7. The high-voltage isolated ground wire status detection method according to claim 6, characterized in that: When the ground line is connected, the fourth capacitor and the fifth capacitor are connected in series and then in parallel with the third capacitor, and the third capacitor is short-circuited. The step of converting the capacitance change between the neutral line and the protective ground line when the ground line is connected into a resonant frequency change includes: The resonant frequency is determined by the transformer and the second capacitor.

8. The high-voltage isolated ground wire status detection method according to claim 6, characterized in that: When the ground line is disconnected, the second capacitor, the third capacitor, the fourth capacitor, the fifth capacitor, and the transformer form a loop, and the step of converting the capacitance change between the neutral line and the protective ground line when the ground line is disconnected into a resonant frequency change includes: The resonant frequency is determined by using the transformer, the second capacitor, and the capacitance parameters of the neutral line and the live line to ground.

9. The high-voltage isolated ground wire status detection method according to claim 6, characterized in that: The steps for converting the capacitance change between the neutral line and the protective ground line when the ground line contact is poor into the resonant frequency change include: When the ground wire has poor contact, the resonant frequency is determined using the ground capacitance parameters of the transformer, the second capacitor, the neutral wire, and the live wire, as well as the contact resistance and equivalent inductance when the ground wire has poor contact.

10. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores computer-executable instructions that can be executed by the processor, and the processor executes the computer-executable instructions to implement the method according to any one of claims 6 to 9.

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