High-voltage leakage protection circuit and leakage analysis chip

Abstract

This invention discloses a high-voltage leakage current protection circuit and a leakage current analysis chip. The high-voltage leakage current protection circuit includes a first current sampling front-end, a second current sampling front-end, an isolation withstand voltage module, and a signal analysis circuit. The first current sampling front-end is used to sample the current of the high-voltage live wire to obtain the live wire current signal. The second current sampling front-end is used to sample the current of the high-voltage neutral wire to obtain the neutral wire current signal. The first current sampling front-end is isolated from the second current sampling front-end by the isolation withstand voltage module. The signal analysis circuit performs vector summation and energy integration on the live wire current signal and the neutral wire current signal to obtain the leakage current energy value, and compares the leakage current energy value with a preset leakage current threshold. This high-voltage leakage current protection circuit improves the accuracy of leakage current detection, reduces the size and cost of the leakage current protection circuit, improves the efficiency of leakage current protection, ensures safety, and reduces the influence of interference signals.

Description

Technical Field

[0001] This invention relates to the field of integrated circuit design, and in particular to a high-voltage leakage protection circuit and a leakage analysis chip. Background Technology

[0002] Conventional high-voltage circuit leakage current protection methods involve acquiring a leakage current signal, after voltage limiting and conversion, using a zero-sequence current transformer and sending it to the leakage protection circuit. The leakage protection circuit then activates its protection mechanism when the leakage current signal reaches or exceeds a preset threshold. Because leakage current is generally very small, zero-sequence current transformers are large, expensive, and have significant errors. Furthermore, the leakage protection circuit activates once the preset threshold is reached or exceeded, making it impossible to quantify or store the leakage current value, thus hindering analysis. Currently, leakage detection chips utilize integrating capacitors for leakage current regulation, which is not very precise. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology, such as large size, high price and large error of zero-sequence current transformer, which leads to low efficiency of leakage protection, and to provide a high-voltage leakage protection circuit and leakage analysis chip.

[0004] The present invention solves the above-mentioned technical problems through the following technical solution:

[0005] This invention provides a high-voltage leakage protection circuit, which includes a first current sampling front end, a second current sampling front end, an isolation withstand voltage module, and a signal analysis circuit.

[0006] The first current sampling front end is used to sample the current of the high-voltage live wire to obtain the live wire current signal, and send the live wire current signal to the signal analysis circuit; the second current sampling front end is used to sample the current of the high-voltage neutral wire to obtain the neutral wire current signal, and send the neutral wire current signal to the signal analysis circuit.

[0007] The first current sampling front end is separated from the second current sampling front end by the isolation withstand voltage module; the isolation withstand voltage module is used to isolate the live wire current signal and the neutral wire current signal.

[0008] The signal analysis circuit is used to perform vector summation and energy integration on the live wire current signal and the neutral wire current signal to obtain the leakage energy value, and compare the leakage energy value with a preset leakage threshold; when the leakage energy value is greater than the leakage threshold, the signal analysis circuit is also used to generate a leakage protection signal.

[0009] Preferably, the isolation withstand voltage module includes an isolation withstand voltage capacitor and an isolation withstand voltage material;

[0010] The isolation withstand voltage capacitor is filled with the isolation withstand voltage material in the middle;

[0011] The isolation withstand voltage module is used to conduct high-frequency signals and isolate low-frequency signals.

[0012] Preferably, the isolation withstand voltage module includes an isolation withstand voltage transformer group;

[0013] The isolation withstand voltage transformer bank includes at least two inductor banks;

[0014] The isolation withstand voltage module is used to conduct high-frequency signals and isolate low-frequency signals.

[0015] Preferably, the first current sampling front end is connected to the high-voltage live wire through a first sampling resistor;

[0016] The second current sampling front end is connected to the high-voltage neutral line through the second sampling resistor.

[0017] Preferably, the high-voltage leakage protection circuit further includes a first analog-to-digital converter module and a second analog-to-digital converter module;

[0018] The first analog-to-digital converter module is communicatively connected to the first current sampling front-end and the signal analysis circuit, respectively; the second analog-to-digital converter module is communicatively connected to the second current sampling front-end and the signal analysis circuit, respectively.

[0019] The first current sampling front end is also used to sample the current of the high-voltage live wire to obtain a live wire current analog signal, and send the live wire current analog signal to the first analog-to-digital conversion module; the first analog-to-digital conversion module is used to convert the live wire current analog signal into a vector live wire current digital signal, and send the live wire current digital signal to the signal analysis circuit;

[0020] The second current sampling front end is used to sample the current of the high-voltage neutral line to obtain a neutral line current analog signal, and send the neutral line current analog signal to the second analog-to-digital conversion module; the second analog-to-digital conversion module is used to convert the neutral line current analog signal into a vector neutral line current digital signal, and send the neutral line current digital signal to the signal analysis circuit;

[0021] The first analog-to-digital converter module is separated from the second analog-to-digital converter module by the isolation withstand voltage module.

[0022] Preferably, the signal analysis circuit includes an adder, an energy integration circuit, a comparator, and a high-frequency clock source;

[0023] The adder is communicatively connected to the first analog-to-digital conversion module, the second analog-to-digital conversion module, and the energy integration circuit, respectively.

[0024] The energy integration circuit is communicatively connected to the comparator and the high-frequency clock source, respectively.

[0025] The adder is used to perform vector summation on the digital signal of the live wire current and the digital signal of the neutral wire current to obtain a vector sum, and sends the vector sum to the energy integration circuit.

[0026] The high-frequency clock source is used to generate a time signal of a first preset frequency and send it to the energy integration circuit.

[0027] The energy integration circuit is used to generate the leakage energy value based on the vector sum and the time signal, and send the leakage energy value to the comparator;

[0028] The comparator is used to compare the leakage energy value with the leakage threshold; when the leakage energy value is greater than the leakage threshold, the comparator is also used to generate a leakage protection signal.

[0029] Preferably, the high-frequency clock source is also communicatively connected to the isolation withstand voltage module;

[0030] The high-frequency clock source is also used to generate a frequency signal of a second preset frequency and send it to the isolation withstand voltage module so that a digital signal with the second preset frequency can pass through the isolation withstand voltage module.

[0031] Preferably, the signal analysis circuit further includes a temperature compensation circuit;

[0032] The temperature compensation circuit is communicatively connected to the high-frequency clock source.

[0033] The temperature compensation circuit is used to collect temperature data and send the temperature data to the high-frequency clock source;

[0034] The high-frequency clock source is also used for frequency calibration based on the temperature data.

[0035] Preferably, the high-voltage leakage protection circuit further includes a communication interface;

[0036] The communication interface is communicatively connected to the energy integration circuit and the comparator, respectively.

[0037] The communication interface is used to receive control commands from an external controller and send them to the energy integration circuit and the comparator, respectively.

[0038] The communication interface is also used to receive the leakage energy value and send it to an external controller.

[0039] Preferably, the high-voltage leakage protection circuit further includes a memory;

[0040] The memory is communicatively connected to both the communication interface and the signal analysis circuit.

[0041] The memory is used to store one or more of the vector sum, the leakage energy value, and the leakage threshold.

[0042] Preferably, the high-voltage leakage protection circuit further includes a drive circuit;

[0043] The driving circuit is communicatively connected to the signal analysis circuit;

[0044] The driving circuit is used to generate a driving signal based on the leakage protection signal to drive the leakage protection switch.

[0045] Preferably, the high-voltage leakage protection circuit further includes a power supply circuit;

[0046] The power supply circuit is electrically connected to the first current sampling front end, the second current sampling front end, and the signal analysis circuit, respectively.

[0047] The present invention also provides a leakage current analysis chip, which includes the high voltage leakage current protection circuit described above.

[0048] The positive and progressive effects of this invention are as follows:

[0049] The high-voltage leakage protection circuit and leakage analysis chip provided by this invention directly sample the current of the live wire and neutral wire through a current sampling front end to obtain the live wire current signal and the neutral wire current signal. Vector summation and energy integration are performed on the live wire current signal and the neutral wire current signal to obtain the leakage energy value, which improves the accuracy of leakage detection, reduces the size and cost of the leakage protection circuit, and improves the efficiency of leakage protection. The isolation withstand voltage module separates the live wire current signal and the neutral wire current signal, ensuring the safety of sampling in the high-voltage leakage protection circuit and reducing the influence of interference signals. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of the circuit structure of the high-voltage leakage protection circuit in Embodiment 1 of the present invention.

[0051] Figure 2 This is a schematic diagram of the circuit structure of the high-voltage leakage protection circuit in Embodiment 2 of the present invention. Detailed Implementation

[0052] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein.

[0053] Example 1

[0054] like Figure 1As shown, this embodiment provides a high-voltage leakage protection circuit. The high-voltage leakage protection circuit includes a first current sampling front-end 1, a second current sampling front-end 2, an isolation withstand voltage module 3, and a signal analysis circuit 4.

[0055] The first current sampling front-end 1 is used to sample the current of the high-voltage live wire to obtain the live wire current signal and send the live wire current signal to the signal analysis circuit 4; the second current sampling front-end 2 is used to sample the current of the high-voltage neutral wire to obtain the neutral wire current signal and send the neutral wire current signal to the signal analysis circuit 4; the first current sampling front-end 1 is separated from the second current sampling front-end 2 by the isolation withstand voltage module 3; the isolation withstand voltage module 3 is used to isolate the live wire current signal and the neutral wire current signal.

[0056] Specifically, in one optional implementation, taking live wire (L-line) current sampling as an example, the first current sampling front-end 1 can directly sample the L-line current through a shunt resistor without passing through a zero-sequence current transformer. After sampling, the sampled live wire current signal is sent to the signal analysis circuit 4; the same applies to the neutral wire (N-line). In the prior art, the acquisition of zero-sequence current is mostly not directly generated by a single zero-sequence current transformer, but rather by synthesizing a zero-sequence current through three current transformers for use by related secondary equipment. Therefore, issues such as the consistency of characteristics of the three current transformers, installation wiring, acquisition channel calibration, and load balance can seriously affect the accuracy of the zero-sequence current. The current sampling front-end directly samples the circuit current through a shunt resistor, improving the accuracy of leakage current detection.

[0057] The first current sampling front-end 1 and the second current sampling front-end 2 are separated by an isolation withstand voltage module 3. The isolation withstand voltage module 3 is manufactured using integrated circuit withstand voltage technology. It can be composed of capacitors filled with SiO2 (silicon dioxide) material, or a transformer assembly consisting of two sets of inductors. The isolation withstand voltage module 3 is characterized by its ability to transmit high-frequency digital signals from one end to the other, while isolating low-frequency high-voltage electrical signals. Both the live wire current signal and the neutral wire current signal are 50Hz (Hertz) high-voltage, low-frequency electrical signals; therefore, the isolation withstand voltage module 3 isolates the live wire current signal and the neutral wire current signal to prevent short circuits.

[0058] The signal analysis circuit 4 is used to perform vector summation and energy integration on the live wire current signal and the neutral wire current signal to obtain the leakage energy value, and compare the leakage energy value with the preset leakage threshold. When the leakage energy value is greater than the leakage threshold, the signal analysis circuit 4 is also used to generate a leakage protection signal.

[0059] Specifically, when there is no leakage current, the current values ​​of the L and N lines should be the same, only in opposite directions. Therefore, the vector sum of the current signals of the L and N lines should be zero. However, when leakage current occurs, the vector sum of the current signals of the L and N lines is not zero. Therefore, the signal analysis circuit 4 superimposes the digital vector sums of the L and N lines and then performs energy integration at a specific time frequency to obtain the leakage current energy value. The signal analysis circuit 4 then compares the leakage current energy value with a preset leakage current threshold to determine whether leakage current has occurred. When leakage current is determined to have occurred, the signal analysis circuit 4 also generates a leakage current protection signal to execute the corresponding leakage current protection measures.

[0060] The high-voltage leakage protection circuit provided in this embodiment directly samples the current of the live wire and neutral wire through a current sampling front end to obtain the live wire current signal and the neutral wire current signal. The live wire current signal and the neutral wire current signal are then vector-summed and energy-integrated to obtain the leakage energy value. This improves the accuracy of leakage detection, reduces the size and cost of the leakage protection circuit, and improves the efficiency of leakage protection. The live wire current signal and the neutral wire current signal are isolated by an isolation withstand voltage module, ensuring the safety of sampling in the high-voltage leakage protection circuit and reducing the influence of interference signals.

[0061] Example 2

[0062] like Figure 2 As shown, the high-voltage leakage protection circuit in this embodiment is a further improvement on Embodiment 1, specifically:

[0063] In one optional embodiment, the isolation withstand voltage module 3 includes an isolation withstand voltage capacitor and an isolation withstand voltage material; the isolation withstand voltage capacitor is filled with the isolation withstand voltage material; the isolation withstand voltage module 3 is used to conduct high-frequency signals and isolate low-frequency signals.

[0064] In another alternative embodiment, the isolation withstand voltage module 3 includes an isolation withstand voltage transformer group; the isolation withstand voltage transformer group includes at least two groups of inductors; the isolation withstand voltage module 3 is used to conduct high-frequency signals and isolate low-frequency signals.

[0065] Specifically, the isolation withstand voltage module 3 is manufactured using integrated circuit withstand voltage technology. The isolation withstand voltage module 3 can be composed of isolation withstand voltage capacitors filled with an isolation withstand voltage material, which can be SiO2. Alternatively, the isolation withstand voltage module 3 can be composed of an isolation withstand voltage transformer group consisting of two sets of inductors. The characteristic of the isolation withstand voltage module 3 is that high-frequency digital signals can be transmitted from one end of the module to the other, but it is isolated from low-frequency electrical signals of high voltage.

[0066] In one optional implementation, the first current sampling front-end 1 is connected to the high-voltage live wire via a first sampling resistor 5; the second current sampling front-end 2 is connected to the high-voltage neutral wire via a second sampling resistor 6. Specifically, the sampling error can be reduced and the accuracy of leakage current detection improved by adjusting the sampling resistors.

[0067] In one optional embodiment, the high-voltage leakage protection circuit further includes a first analog-to-digital converter module 7 and a second analog-to-digital converter module 8; the first analog-to-digital converter module 7 is communicatively connected to the first current sampling front-end 1 and the signal analysis circuit 4, respectively; the second analog-to-digital converter module 8 is communicatively connected to the second current sampling front-end 2 and the signal analysis circuit 4, respectively.

[0068] The first current sampling front-end 1 is also used to sample the current of the high-voltage live wire to obtain a live wire current analog signal, and send the live wire current analog signal to the first analog-to-digital conversion module 7; the first analog-to-digital conversion module 7 is used to convert the live wire current analog signal into a vector live wire current digital signal, and send the live wire current digital signal to the signal analysis circuit 4; the second current sampling front-end 2 is used to sample the current of the high-voltage neutral wire to obtain a neutral wire current analog signal, and send the neutral wire current analog signal to the second analog-to-digital conversion module 8; the second analog-to-digital conversion module 8 is used to convert the neutral wire current analog signal into a vector neutral wire current digital signal, and send the neutral wire current digital signal to the signal analysis circuit 4.

[0069] The first analog-to-digital converter (ADC) module 7 is separated from the second ADC module 8 by the isolation withstand voltage module 3. Specifically, the first current sampling front-end 1 and the first ADC module 7 are located on one side of the isolation withstand voltage module 3, and the second current sampling front-end 2 and the second ADC module 8 are located on the opposite side of the isolation withstand voltage module 3.

[0070] In one optional implementation, the signal analysis circuit 4 includes an adder 9, an energy integration circuit 10, a comparator 11, and a high-frequency clock source 12; the adder 9 is communicatively connected to the first analog-to-digital converter module 7, the second analog-to-digital converter module 8, and the energy integration circuit 10; the energy integration circuit 10 is communicatively connected to the comparator 11 and the high-frequency clock source 12.

[0071] Adder 9 is used to perform vector summation on the digital signal of live wire current and digital signal of neutral wire current to obtain a vector sum, and sends the vector sum to energy integration circuit 10; high frequency clock source 12 is used to generate a time signal of a first preset frequency and send it to energy integration circuit 10; energy integration circuit 10 is used to generate leakage energy value based on vector sum and time signal, and sends leakage energy value to comparator 11.

[0072] Specifically, when leakage occurs, the vector sum of the current signals of the L line and N line is not zero. Therefore, after the adder 9 superimposes the digital vector sums of the L line and N line, it performs energy integration at a specific time frequency. Energy integration requires a time signal, such as detecting leakage at different times like 1ms or 3ms. The high-frequency clock source 12 can provide the required frequency, convert the frequency into duration, and use it for the energy integration circuit 10. After integration, the leakage energy value is obtained.

[0073] Comparator 11 is used to compare the leakage energy value with the leakage threshold; when the leakage energy value is greater than the leakage threshold, comparator 11 is also used to generate a leakage protection signal. Specifically, the leakage energy value is sent to comparator 11, which compares the leakage energy value with a preset leakage threshold to determine whether leakage has occurred; when leakage is determined to have occurred, comparator 11 also generates a leakage protection signal to execute corresponding leakage protection measures.

[0074] In an optional embodiment, the high-frequency clock source 12 is also communicatively connected to the isolation withstand voltage module 3; the high-frequency clock source 12 is also used to generate a frequency signal of a second preset frequency and send it to the isolation withstand voltage module 3 so that a digital signal having the second preset frequency can pass through the isolation withstand voltage module 3. Specifically, the digital signal is transmitted from one side of the isolation withstand voltage module 3 to the other side and is a characteristic high frequency, therefore a clock source is needed for high-frequency modulation, and the high-frequency clock source can provide this frequency signal.

[0075] In an optional implementation, the signal analysis circuit 4 further includes a temperature compensation circuit 13; the temperature compensation circuit 13 is communicatively connected to the high-frequency clock source 12; the temperature compensation circuit 13 is used to collect temperature data and send the temperature data to the high-frequency clock source 12; the high-frequency clock source 12 is also used to perform frequency calibration based on the temperature data. Specifically, the function of the temperature compensation circuit is that, due to changes in temperature, the clock source frequency will change, and the temperature compensation circuit 13 can perform temperature sampling and generate a temperature curve, and the high-frequency clock source 12 can achieve automatic calibration of the clock source across the entire temperature range based on the temperature curve.

[0076] In one optional embodiment, the high-voltage leakage protection circuit further includes a communication interface 14; the communication interface 14 is communicatively connected to the energy integration circuit 10 and the comparator 11 respectively; the communication interface 14 is used to receive control commands from an external controller and send them to the energy integration circuit 10 and the comparator 11 respectively; the communication interface 14 is also used to receive leakage energy values ​​and send them to the external controller. Specifically, the communication interface 14 is used for communication between the high-voltage leakage protection circuit and an external MCU (Microcontroller Unit). The MCU can set the leakage threshold according to the needs of the system to achieve leakage detection at different thresholds; after the MCU reads the leakage energy value through the communication interface 14, it can analyze or statistically analyze the leakage energy value to determine what kind of equipment is leaking current.

[0077] In one optional embodiment, the high-voltage leakage protection circuit further includes a memory 15; the memory 15 is communicatively connected to the communication interface and the signal analysis circuit 4 respectively; the memory 15 is used to store vector sums, leakage energy values ​​and leakage thresholds.

[0078] In one optional embodiment, the high-voltage leakage protection circuit further includes a drive circuit 16; the drive circuit 16 is communicatively connected to the signal analysis circuit 4; the drive circuit 16 is used to generate a drive signal based on the leakage protection signal to drive the leakage protection switch.

[0079] In one optional embodiment, the high-voltage leakage protection circuit further includes a power supply circuit 17; the power supply circuit 17 is electrically connected to the first current sampling front-end 1, the second current sampling front-end 2, and the signal analysis circuit 4, respectively. Specifically, the power supply circuit 17 can be an AC-DC (Alternating Current-Direct Current) conversion circuit, which can be a resistor voltage divider structure or an AC-DC modulation circuit, designed to draw power from the live wire and neutral wire and convert it into a regulated DC power supply to power each module of the high-voltage leakage protection circuit.

[0080] The high-voltage leakage protection circuit provided in this embodiment directly samples the current of the live wire and neutral wire through a current sampling front end to obtain the live wire current signal and the neutral wire current signal. Vector summation and energy integration are performed on the live wire current signal and the neutral wire current signal to obtain the leakage energy value, improving the accuracy of leakage detection, reducing the size and cost of the leakage protection circuit, and improving the efficiency of leakage protection. An isolation withstand voltage module separates the live wire current signal and the neutral wire current signal, ensuring the safety of sampling in the high-voltage leakage protection circuit and reducing the influence of interference signals. It can be connected to an external controller to set the leakage threshold, enabling leakage detection at different thresholds, quantifying and recording the leakage value for analysis. Power is drawn from the detection circuit through a power supply circuit, eliminating the need for an additional power supply.

[0081] Example 3

[0082] This embodiment improves a high-voltage sampling leakage current analysis chip, which includes the high-voltage leakage current protection circuit of Embodiment 1 or Embodiment 2.

[0083] The high-voltage leakage protection circuit provided in this embodiment improves the accuracy of leakage detection, reduces the size and cost of the leakage protection circuit, improves the efficiency of leakage protection, ensures the safety of sampling in the high-voltage leakage protection circuit, and reduces the influence of interference signals.

[0084] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A high-voltage leakage protection circuit, characterized in that, The high-voltage leakage protection circuit includes a first current sampling front-end, a second current sampling front-end, an isolation withstand voltage module, and a signal analysis circuit; the signal analysis circuit includes an adder, an energy integration circuit, a comparator, and a high-frequency clock source. The first current sampling front end is used to sample the current of the high-voltage live wire to obtain the live wire current signal, and send the live wire current signal to the signal analysis circuit; The second current sampling front end is used to sample the current of the high-voltage neutral line to obtain the neutral line current signal, and send the neutral line current signal to the signal analysis circuit; The first current sampling front end is isolated from the second current sampling front end through the isolation withstand voltage module; The isolation withstand voltage module is used to isolate the live wire current signal and the neutral wire current signal; The signal analysis circuit is used to perform vector summation and energy integration on the live wire current signal and the neutral wire current signal to obtain the leakage energy value, and compare the leakage energy value with a preset leakage threshold; when the leakage energy value is greater than the leakage threshold, the signal analysis circuit is also used to generate a leakage protection signal; The signal analysis circuit is used to perform vector summation and energy integration on the live wire current signal and the neutral wire current signal to obtain the leakage energy value. Specifically, this includes: The adder is used to perform vector summation on the digital signal of live wire current and the digital signal of neutral wire current to obtain a vector sum, and sends the vector sum to the energy integration circuit; The high-frequency clock source is used to generate a time signal of a first preset frequency and send it to the energy integration circuit. The energy integration circuit is used to generate the leakage energy value based on the vector sum and the time signal, and send the leakage energy value to the comparator.

2. The high-voltage leakage protection circuit as described in claim 1, characterized in that, The isolation withstand voltage module includes an isolation withstand voltage capacitor and an isolation withstand voltage material; The isolation withstand voltage capacitor is filled with the isolation withstand voltage material in the middle; The isolation withstand voltage module is used to conduct high-frequency signals and isolate low-frequency signals.

3. The high-voltage leakage protection circuit as described in claim 1, characterized in that, The isolation withstand voltage module includes an isolation withstand voltage transformer group; The isolation withstand voltage transformer bank includes at least two inductor banks; The isolation withstand voltage module is used to conduct high-frequency signals and isolate low-frequency signals.

4. The high-voltage leakage protection circuit as described in claim 1, characterized in that, The first current sampling front end is connected to the high-voltage live wire through a first sampling resistor; The second current sampling front end is connected to the high-voltage neutral line through the second sampling resistor.

5. The high-voltage leakage protection circuit as described in claim 1, characterized in that, The high-voltage leakage protection circuit also includes a first analog-to-digital conversion module and a second analog-to-digital conversion module; The first analog-to-digital converter module is communicatively connected to the first current sampling front-end and the signal analysis circuit, respectively; the second analog-to-digital converter module is communicatively connected to the second current sampling front-end and the signal analysis circuit, respectively. The first current sampling front end is also used to sample the current of the high-voltage live wire to obtain a live wire current analog signal, and send the live wire current analog signal to the first analog-to-digital conversion module; the first analog-to-digital conversion module is used to convert the live wire current analog signal into a vector live wire current digital signal, and send the live wire current digital signal to the signal analysis circuit; The second current sampling front end is used to sample the current of the high-voltage neutral line to obtain a neutral line current analog signal, and send the neutral line current analog signal to the second analog-to-digital conversion module; the second analog-to-digital conversion module is used to convert the neutral line current analog signal into a vector neutral line current digital signal, and send the neutral line current digital signal to the signal analysis circuit; The first analog-to-digital converter module is separated from the second analog-to-digital converter module by the isolation withstand voltage module.

6. The high-voltage leakage protection circuit as described in claim 5, characterized in that, The adder is communicatively connected to the first analog-to-digital conversion module, the second analog-to-digital conversion module, and the energy integration circuit, respectively. The energy integration circuit is communicatively connected to the comparator and the high-frequency clock source, respectively. The comparator is used to compare the leakage energy value with the leakage threshold; when the leakage energy value is greater than the leakage threshold, the comparator is also used to generate a leakage protection signal.

7. The high-voltage leakage protection circuit as described in claim 6, characterized in that, The high-frequency clock source is also communicatively connected to the isolation withstand voltage module; The high-frequency clock source is also used to generate a frequency signal of a second preset frequency and send it to the isolation withstand voltage module so that a digital signal with the second preset frequency can pass through the isolation withstand voltage module.

8. The high-voltage leakage protection circuit as described in claim 6, characterized in that, The signal analysis circuit also includes a temperature compensation circuit. The temperature compensation circuit is communicatively connected to the high-frequency clock source. The temperature compensation circuit is used to collect temperature data and send the temperature data to the high-frequency clock source; The high-frequency clock source is also used for frequency calibration based on the temperature data.

9. The high-voltage leakage protection circuit as described in claim 6, characterized in that, The high-voltage leakage protection circuit also includes a communication interface; The communication interface is communicatively connected to the energy integration circuit and the comparator, respectively. The communication interface is used to receive control commands from an external controller and send them to the energy integration circuit and the comparator, respectively. The communication interface is also used to receive the leakage energy value and send it to an external controller.

10. The high-voltage leakage protection circuit as described in claim 9, characterized in that, The high-voltage leakage protection circuit also includes a memory; The memory is communicatively connected to both the communication interface and the signal analysis circuit. The memory is used to store one or more of the vector sum, the leakage energy value, and the leakage threshold.

11. The high-voltage leakage protection circuit as described in claim 1, characterized in that, The high-voltage leakage protection circuit also includes a drive circuit; The driving circuit is communicatively connected to the signal analysis circuit; The driving circuit is used to generate a driving signal based on the leakage protection signal to drive the leakage protection switch.

12. The high-voltage leakage protection circuit as described in claim 1, characterized in that, The high-voltage leakage protection circuit also includes a power supply circuit; The power supply circuit is electrically connected to the first current sampling front end, the second current sampling front end, and the signal analysis circuit, respectively.

13. A leakage current analysis chip, characterized in that, The leakage current analysis chip includes a high-voltage leakage current protection circuit as described in any one of claims 1-12.

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