High-voltage leakage protection circuit, detection method thereof, protection system and medium

Abstract

The invention relates to the technical field of electric leakage detection, and discloses a high-voltage electric leakage protection circuit, a detection method thereof, a protection system and a medium. The circuit comprises a current acquisition module which is connected in series with a high / low-side high-voltage power supply line of a high-voltage power supply and is used for acquiring a high-side analog signal and a low-side analog signal of the high-voltage power supply; the analog-to-digital conversion module is electrically connected with a sampling output end of the current acquisition module through a signal sampling end of the analog-to-digital conversion module, and is used for respectively converting high / low-side analog signals sent by the current acquisition module into high / low-side digital signals through analog-to-digital conversion; and the electric leakage detection module is connected in series between the high / low-side high-voltage power supply line and the load, is connected with the data output end of the analog-to-digital conversion module, and is used for determining an electric leakage current value according to the high-side digital signal and the low-side digital signal, and carrying out electric leakage protection according to an electric leakage protection signal determined by the electric leakage current value and a preset electric leakage threshold. The invention aims to improve the reliability of leakage detection of the high-voltage direct-current power supply line so as to ensure the safety of electricity utilization.

Description

Technical Field

[0001] The present application relates to the technical field of leakage detection, and in particular to a high-voltage leakage protection circuit and a detection method, a protection system and a medium thereof. Background Art

[0002] With the rapid development of modern power systems, high-voltage direct current transmission technology has been widely used in the fields of long-distance power transmission, urban power grid transformation, and renewable energy access due to its high efficiency and stability. Users have also put forward higher requirements for leakage detection of high-voltage direct current power supply lines.

[0003] As the core component of power transmission, the stability and safety of the high-voltage DC power supply line's operating state are directly related to the reliability and safety of the entire power system. However, in actual operation, due to the complexity of the power line laying environment, the harsh operating conditions, the aging of power line materials, improper construction and other factors, leakage problems in high-voltage DC power supply lines occur from time to time, which not only leads to energy loss, but also may cause load equipment failure, data errors, and even cause fires, electric shocks and other safety accidents, posing a serious threat to people's lives and property. Therefore, how to improve the reliability of leakage detection of high-voltage DC power supply lines to ensure power safety is a technical problem that needs to be solved urgently.

[0004] The above contents are only used to assist in understanding the technical solution of the present application and do not constitute an admission that the above contents are prior art.

[0005] Application Contents

[0006] The main purpose of this application is to provide a high-voltage leakage protection circuit and its detection method, protection system and medium, aiming to improve the reliability of leakage detection of high-voltage DC power supply lines to ensure power safety.

[0007] To achieve the above object, the present application provides a high voltage leakage protection circuit, the high voltage leakage protection circuit comprising:

[0008] A current acquisition module, wherein the current acquisition module is connected in series with a high-side high-voltage power supply line and a low-side high-voltage power supply line of the high-voltage power supply, respectively, and the current acquisition module is configured to obtain a high-side analog signal and a low-side analog signal of the high-voltage power supply;

[0009] An analog-to-digital conversion module, wherein a signal sampling end of the analog-to-digital conversion module is electrically connected to a sampling output end of the current acquisition module, and the analog-to-digital conversion module is configured to convert the high-side analog signal and the low-side analog signal sent by the current acquisition module into high-side digital signals and low-side digital signals respectively;

[0010] A leakage detection module, wherein the leakage detection module is respectively connected in series between the high-side high-voltage power supply line and the load, and between the low-side high-voltage power supply line and the load, the signal input end of the leakage detection module is electrically connected to the data output end of the analog-to-digital conversion module, and the leakage detection module is configured to receive the high-side digital signal and the low-side digital signal output by the analog-to-digital conversion module, and determine a leakage current value based on the high-side digital signal and the low-side digital signal, determine a leakage protection signal based on the leakage current value and a preset leakage threshold, and perform leakage protection based on the leakage protection signal.

[0011] In one embodiment, the current acquisition module includes a first shunt resistor, a second shunt resistor, a high-side voltage isolation unit, and a low-side voltage isolation unit;

[0012] The first shunt resistor is connected in series between the high-side voltage end of the high-voltage power supply and the high-side high-voltage power supply line, and the second shunt resistor is connected in series between the low-side voltage end of the high-voltage power supply and the low-side high-voltage power supply line;

[0013] The pads at both ends of the first shunt resistor constitute a high-side voltage collection path electrically connected to the voltage input end of the high-side voltage isolation unit, and the pads at both ends of the second shunt resistor constitute a low-side voltage collection path electrically connected to the voltage input end of the low-side voltage isolation unit;

[0014] The high-side power supply end of the high-side voltage isolation unit constitutes the high-side interface in the sampling output end, and the low-side power supply end of the low-side voltage isolation unit constitutes the low-side interface in the sampling output end, which are electrically connected to the signal sampling end of the analog-to-digital conversion module respectively.

[0015] In one embodiment, the high-side voltage isolation unit includes a first resistor, a second resistor, a first capacitor and a first isolation amplifier;

[0016] The first end of the first resistor is electrically connected to one of the two end pads of the first shunt resistor, and the first end of the second resistor is electrically connected to the other of the two end pads of the first shunt resistor;

[0017] The second end of the first resistor is electrically connected to the first end of the first capacitor and the first end of the first isolation amplifier respectively, and the second end of the second resistor is electrically connected to the second end of the first capacitor and the second end of the first isolation amplifier respectively;

[0018] The third terminal of the first isolation amplifier constitutes the high-side power supply terminal of the high-side voltage isolation unit and is electrically connected to the signal sampling terminal of the analog-to-digital conversion module.

[0019] In one embodiment, the low-side voltage isolation unit includes a third resistor, a fourth resistor, a second capacitor, and a second isolation amplifier;

[0020] The first end of the third resistor is electrically connected to one of the two end pads of the second shunt resistor, and the first end of the fourth resistor is electrically connected to the other of the two end pads of the second shunt resistor;

[0021] The second end of the third resistor is electrically connected to the first end of the second capacitor and the first end of the second isolation amplifier respectively, and the second end of the fourth resistor is electrically connected to the second end of the second capacitor and the second end of the second isolation amplifier respectively;

[0022] The third terminal of the second isolation amplifier constitutes a low-side power supply terminal of the low-side voltage isolation unit and is electrically connected to the signal sampling terminal of the analog-to-digital conversion module.

[0023] In one embodiment, the analog-to-digital conversion module includes a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a third capacitor, a fourth capacitor, and a differential input component;

[0024] The first end of the fifth resistor and the first end of the sixth resistor constitute a high-side sampling interface in the signal sampling end, and are electrically connected to the high-side interface in the sampling output end;

[0025] The first end of the seventh resistor and the first end of the eighth resistor constitute a low-side sampling interface in the signal sampling end, and are electrically connected to the low-side interface in the sampling output end;

[0026] The first end of the third capacitor is electrically connected to the second end of the fifth resistor and the high-side negative pin of the differential input component, the second end of the third capacitor is electrically connected to the second end of the sixth resistor and the high-side positive pin of the differential input component, the first end of the fourth capacitor is electrically connected to the second end of the seventh resistor and the low-side negative pin of the differential input component, and the second end of the fourth capacitor is electrically connected to the second end of the eighth resistor and the low-side positive pin of the differential input component;

[0027] The data interface of the differential input component constitutes a data output end of the analog-to-digital conversion module and is electrically connected to the signal input end of the leakage detection module.

[0028] In one embodiment, the leakage detection module includes a control unit, a positive leakage protection unit and a negative leakage protection unit;

[0029] The analog-to-digital conversion interface of the control unit constitutes a signal input end of the leakage detection module and is electrically connected to the data output end of the analog-to-digital conversion module, and the control interface of the control unit is electrically connected to the positive leakage protection unit and the negative leakage protection unit respectively;

[0030] The positive leakage protection unit is connected in series between the high-side high-voltage power supply line and the load, and the negative leakage protection unit is connected in series between the low-side high-voltage power supply line and the load.

[0031] In one embodiment, the positive electrode leakage protection unit includes a first optical isolation driver and a first switch tube, and the negative electrode leakage protection unit includes a second optical isolation driver and a second switch tube;

[0032] The anode end of the first optical isolation driver and the anode end of the second optical isolation driver are electrically connected to the control interface of the control unit respectively, and the cathode end of the first optical isolation driver and the cathode end of the second optical isolation driver are grounded respectively;

[0033] The first passage end of the first switch tube is electrically connected to the high-side high-voltage power supply line, the second passage end of the first switch tube is electrically connected to the load, the control end of the first switch tube is electrically connected to the first output end of the first optical isolation driver, and the second output end of the first optical isolation driver is electrically connected between the second passage end of the first switch tube and the load;

[0034] The first passage end of the second switch tube is electrically connected to the low-side high-voltage power supply line, the second passage end of the second switch tube is electrically connected to the load, the control end of the second switch tube is electrically connected to the first output end of the second optical isolation driver, and the second output end of the second optical isolation driver is electrically connected between the second passage end of the second switch tube and the load.

[0035] In addition, to achieve the above-mentioned purpose, the present application provides a leakage detection method for a high-voltage leakage protection circuit, the leakage detection method is applied to the above-mentioned high-voltage leakage protection circuit, and the leakage detection method includes:

[0036] Acquire the high-side analog signal and low-side analog signal of the high-voltage power supply through the current acquisition module;

[0037] The high-side analog signal and the low-side analog signal sent by the current acquisition module are converted into high-side digital signals and low-side digital signals respectively through an analog-to-digital conversion module;

[0038] The high-side digital signal and the low-side digital signal output by the analog-to-digital conversion module are received through the leakage detection module, and the leakage current value is determined according to the high-side digital signal and the low-side digital signal, and the leakage protection signal is determined according to the leakage current value and a preset leakage threshold, and leakage protection is performed according to the leakage protection signal.

[0039] In addition, to achieve the above-mentioned purpose, the present application provides a leakage protection system, the leakage protection system comprising the above-mentioned display panel; or,

[0040] The leakage protection system includes a processor, a memory, and a leakage detection program for a high-voltage leakage protection circuit stored in the memory and executable by the processor, wherein when the leakage detection program is executed by the processor, the steps of the leakage detection method for the high-voltage leakage protection circuit described above are implemented.

[0041] In addition, to achieve the above-mentioned purpose, the present application provides a medium, wherein the storage medium is a computer-readable storage medium, and a computer program is stored on the computer-readable storage medium. When the computer program is executed by a processor, the steps of the leakage detection method of the above-mentioned high-voltage leakage protection circuit are implemented.

[0042] In summary, the present application provides a high-voltage leakage protection circuit and its detection method, protection system and medium, which realizes the user's electricity safety by improving the reliability of leakage detection of high-voltage DC power supply lines. Specifically, the high-voltage leakage protection circuit provided in the present application integrates a current acquisition module, an analog-to-digital conversion module and a leakage detection module. The present application connects the current acquisition module in series between the high-side high-voltage power supply line and the low-side high-voltage power supply line of the high-voltage power supply so as to collect the high-side analog signal and the low-side analog signal of the high-voltage power supply in real time; next, according to the electrical connection between the signal sampling end of the analog-to-digital conversion module and the sampling output end of the current acquisition module, the analog-to-digital conversion module can immediately convert the high-side analog signal and the low-side analog signal sent by the current acquisition module into high-side digital signals and low-side digital signals respectively, thereby providing a reliable and effective digital signal for the leakage detection module connected in series between the high-side high-voltage power supply line / low-side high-voltage power supply line and the load. Data support; next, through the electrical connection between the signal input end of the leakage detection module and the data output end of the analog-to-digital conversion module, the leakage detection module can immediately receive the high-side digital signal and the low-side digital signal output by the analog-to-digital conversion module, and can accurately obtain the leakage current value based on the high-side digital signal and the low-side digital signal, and immediately generate a reliable and accurate leakage protection signal based on the leakage current value and the preset leakage threshold, thereby significantly improving the response speed and reliability of leakage detection; next, effective leakage protection is performed based on the leakage protection signal, thereby avoiding load equipment failures, data errors, and safety accidents such as fire and electric shock caused by leakage of the high-voltage DC power supply line, thereby ensuring the user's electricity safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is a schematic diagram of the overall structure of the high voltage leakage protection circuit of this application;

[0044] Figure 2 It is a schematic diagram of the leakage detection signal transmission path of the high-voltage leakage protection circuit of the present application;

[0045] Figure 3 This is the PCB routing diagram of the Kelvin connection of the high-precision shunt resistor;

[0046] Figure 4 It is a circuit diagram of the high voltage leakage protection circuit of the present application;

[0047] Figure 5 It is a flow chart of the first embodiment of the leakage detection method of the high-voltage leakage protection circuit of the present application;

[0048] Figure 6 This is a schematic diagram of the device structure of the hardware operating environment involved in this application.

[0049] Description of Figure Numbers:

[0050] 10. Current acquisition module; 20. Analog-to-digital conversion module; 30. Leakage detection module; H1. High-side high-voltage power supply line; L1. Low-side high-voltage power supply line; R SH1 , the first shunt resistor; R SH2 , second shunt resistor; 101, high-side voltage isolation unit; 102, low-side voltage isolation unit; R1, first resistor; R2, second resistor; C1, first capacitor; U1, first isolation amplifier; R3, third resistor; R4, fourth resistor; C2, second capacitor; U2, second isolation amplifier; R5, fifth resistor; R6, sixth resistor;

[0051] R7, seventh resistor; R8, eighth resistor; C3, third capacitor; C4, fourth capacitor; A1, differential input component; 301, control unit; 302, positive leakage protection unit; 303, negative leakage protection unit;

[0052] U3, first optical isolation driver; Q1, first switch tube; U4, second optical isolation driver; Q2, second switch tube.

[0053] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0054] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0055] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0056] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0057] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0058] In addition, in this application, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0059] With the rapid development and widespread application of high-voltage direct current transmission technology, the position of high-voltage direct current power lines in the power system is becoming increasingly important. High-voltage direct current transmission has the advantages of large transmission capacity, low line loss, easy adjustment and control, and has become an important part of the modern power system. However, due to the complex laying environment of the power line, harsh operating conditions, aging of power line materials, improper construction and other reasons, leakage problems of high-voltage direct current power lines occur from time to time, seriously threatening the safe and stable operation of the power system.

[0060] At present, the detection technologies for leakage in high-voltage power supply lines mainly include Hall sensors and fluxgate sensors. Although Hall sensors have the advantages of no power loss and high-level insulation withstand voltage, they have the disadvantages of large size, large initial offset, serious noise and signal interference, poor linearity, low stability, high temperature coefficient and limited measurement range, which limit their application in high-voltage and high-precision current measurement. Although fluxgate sensors have high accuracy, fast response, low power consumption and wide measurement range, they also have problems such as large size, high price and zero bias, which makes it difficult to meet the high requirements in practical applications.

[0061] In order to solve the above-mentioned defects of the existing high-voltage power supply line leakage detection technology, the present application provides a high-voltage leakage protection circuit and its detection method, protection system and medium.

[0062] In one embodiment of the present application, refer to Figure 1 As shown, Figure 1 This is a schematic diagram of the overall structure of the high voltage leakage protection circuit of this application. Figure 1 The solid arrow shown is the direction of the current in the power supply circuit from the high voltage power supply to the load. Figure 1 The dashed arrow shown is a signal transmission path used for leakage detection in a high-voltage leakage protection circuit; the high-voltage leakage protection circuit includes:

[0063] The current acquisition module 10 is connected in series with the high-side high-voltage power supply line H1 and the low-side high-voltage power supply line L1 of the high-voltage power supply, and the current acquisition module 10 is configured to obtain the high-side analog signal and the low-side analog signal of the high-voltage power supply.

[0064] In this embodiment, the current acquisition module 10 is respectively connected in series with the high-side high-voltage power supply line H1 and the low-side high-voltage power supply line L1 of the high-voltage power supply, thereby realizing real-time detection of the output current of the high-voltage power supply, so that the current acquisition module 10 can accurately collect the high-side analog signal generated by the high-voltage power supply on the high-side high-voltage power supply line H1 and the low-side analog signal generated by the high-voltage power supply on the low-side high-voltage power supply line L1 in real time, thereby realizing effective monitoring and acquisition of the current.

[0065] It should be noted that the high-side high-voltage power supply line H1 and the low-side high-voltage power supply line L1 can be understood as high-voltage DC power supply lines; the high-side analog signal refers to the voltage signal obtained by the current acquisition module 10 converting the current signal transmitted by the high-side high-voltage power supply through the high-side high-voltage power supply line H1; the low-side analog signal refers to the voltage signal obtained by the current acquisition module 10 converting the current signal transmitted by the high-voltage power supply through the low-side high-voltage power supply line L1, wherein the current acquisition module 10 may include a first shunt resistor and a second shunt resistor, the first shunt resistor is connected in series to the high-side high-voltage power supply line H1, and the second shunt resistor is connected in series to the low-side high-voltage power supply line L1.

[0066] The analog-to-digital conversion module 20 has a signal sampling end electrically connected to a sampling output end of the current acquisition module 10, and is configured to convert the high-side analog signal and the low-side analog signal sent by the current acquisition module 10 into high-side digital signals and low-side digital signals, respectively.

[0067] In this embodiment, the signal sampling end of the analog-to-digital conversion module 20 provided in the present application is composed of two analog input channels consisting of a high-side sampling interface and a low-side sampling interface, which are electrically connected to the high-side interface and the low-side interface in the sampling output end respectively, so that the high-side analog signal converted and conditioned from the first shunt resistor on the high-side high-voltage power supply line H1 of the high-voltage power supply, and the low-side analog signal converted and conditioned from the second shunt resistor on the low-side high-voltage power supply line L1 of the high-voltage power supply can be collected simultaneously, and the high-side analog signal and the low-side analog signal are converted into high-side digital signals and low-side digital signals respectively, and then transmitted to the leakage detection module 30, thereby providing reliable and effective data support for the leakage detection module 30 connected in series between the high-side high-voltage power supply line H1 / low-side high-voltage power supply line L1 and the load.

[0068] A leakage detection module 30 is respectively connected in series between the high-side high-voltage power supply line H1 and the load, and between the low-side high-voltage power supply line L1 and the load. The signal input end of the leakage detection module 30 is electrically connected to the data output end of the analog-to-digital conversion module 20. The leakage detection module 30 is configured to receive the high-side digital signal and the low-side digital signal output by the analog-to-digital conversion module 20, and determine the leakage current value according to the high-side digital signal and the low-side digital signal, determine the leakage protection signal according to the leakage current value and a preset leakage threshold, and perform leakage protection according to the leakage protection signal.

[0069] In this embodiment, according to the electrical connection between the signal input terminal of the leakage detection module 30 and the data output terminal of the analog-to-digital conversion module 20, after the control unit 301 in the leakage detection module 30 receives the high-side digital signal and the low-side digital signal sent by the analog-to-digital conversion module 20, the high-side current value can be accurately calculated according to the high-side digital signal and the resistance value of the first shunt resistor, and the low-side current value can be accurately calculated according to the low-side digital signal and the resistance value of the second shunt resistor, and the leakage current value of the power supply circuit from the high-voltage power supply to the load can be efficiently and accurately calculated according to the difference between the high-side current value and the low-side current value; next, it is determined whether the leakage current value exceeds the preset leakage threshold value, and if the leakage current value exceeds the preset leakage threshold value, the triggering The control unit 301 automatically outputs a leakage protection signal to the positive leakage protection unit 302 and the negative leakage protection unit 303 in the leakage detection module 30 at the same time, so that the positive leakage protection unit 302 and the negative leakage protection unit 303 synchronously respond to the leakage protection signal, so as to immediately cut off the electrical connection between the high-side high-voltage power supply line H1 and the load, and the electrical connection between the low-side high-voltage power supply line L1 and the load, thereby significantly improving the response speed and reliability of leakage detection, so that the power supply circuit from the high-voltage power supply to the load can be quickly disconnected in the event of leakage of the high-voltage DC power supply line, avoiding load equipment failure, data error, fire, electric shock and other safety accidents caused by leakage of the high-voltage DC power supply line, thereby ensuring the user's power safety.

[0070] It should be noted that the preset leakage threshold can be customized according to application requirements, and this application does not impose any restrictions here. For example, the preset leakage threshold can be 1mA, which is only one implementation of this application.

[0071] Furthermore, in some feasible embodiments, Figure 2 It is a schematic diagram of the leakage detection signal transmission path of the high-voltage leakage protection circuit of the present application. The current acquisition module 10 includes a first shunt resistor, a second shunt resistor, a high-side voltage isolation unit 101 and a low-side voltage isolation unit 102; the first shunt resistor is connected in series between the high-side voltage end of the high-voltage power supply and the high-side high-voltage power supply line H1, and the second shunt resistor is connected in series between the low-side voltage end of the high-voltage power supply and the low-side high-voltage power supply line L1; the two-end pads of the first shunt resistor constitute a high-side voltage acquisition path and are electrically connected to the voltage input end of the high-side voltage isolation unit 101, and the two-end pads of the second shunt resistor constitute a low-side voltage acquisition path and are electrically connected to the voltage input end of the low-side voltage isolation unit 102; the high-side power supply end of the high-side voltage isolation unit 101 constitutes the high-side interface in the sampling output end, and the low-side power supply end of the low-side voltage isolation unit 102 constitutes the low-side interface in the sampling output end, which are respectively electrically connected to the signal sampling end of the analog-to-digital conversion module 20.

[0072] In this embodiment, the first shunt resistor is connected in series between the high-side voltage end of the high-voltage power supply and the high-side high-voltage power supply line H1. When the current output by the high-voltage power supply flows through the first shunt resistor, the high-side voltage signal is obtained through the voltages at both ends of the pads at both ends of the first shunt resistor, and then the high-side voltage signal on the high-side high-voltage side is isolated and amplified by the high-side voltage isolation unit 101 for collection by the low-voltage side circuit (i.e., the high-side interface AIN1P and AIN1N of the analog-to-digital conversion module 20); at the same time, the second shunt resistor is connected in series with the low-side voltage end of the high-voltage power supply. Between the voltage end and the low-side high-voltage power supply line L1, when the current output by the high-voltage power supply flows through the second shunt resistor, the low-side voltage signal is obtained through the voltage at both ends of the pads at both ends of the second shunt resistor, and then after isolation and amplification processing by the low-side voltage isolation unit 102, the low-side voltage signal on the low-side high-voltage side is isolated and amplified for collection by the low-voltage side circuit (i.e., the low-side interface AIN2P and AIN2N in the analog-to-digital conversion module 20), so that the analog-to-digital conversion module 20 can accurately detect the voltage difference between the high-side high-voltage power supply line H1 and the low-side high-voltage power supply line L1.

[0073] It should be noted that the high-side voltage isolation unit 101 and the low-side voltage isolation unit 102 are both the same voltage isolation components, which include an analog filtering circuit and an isolation amplifier, so as to realize the function of isolating and amplifying the weak analog signals (i.e., high-side voltage signals and low-side analog signals) collected on the high-voltage side and converting them into low-voltage side analog signals (i.e., high-side analog signals and low-side analog signals); wherein, the analog filtering circuit uses RC filtering, and the cut-off frequency is designed to be one order of magnitude smaller than the modulation frequency inside the isolation amplifier, for details, please refer to the device manual; the isolation amplifier uses a low-voltage side single power supply chip with internally integrated isolated DC / DC (Direct Current to Direct Current, DC chopper) and LDO (Low Dropout Regulator, low voltage difference linear regulator), so there is no need to add a high-side power supply circuit to the external circuit, and at the same time, the LDO can optimize the power supply ripple, reduce the interference of the power supply to the analog small signal, and improve the signal-to-noise ratio of the isolation amplifier. Since the isolation amplifier with internal integrated DC / DC and LDO generally has a high CMTI (Common Mode Transient Immunity), it can not only effectively isolate the high-voltage and low-voltage areas to cope with complex electromagnetic environments, thereby protecting the low-voltage side devices from high-voltage shocks, but also has excellent DC accuracy and low temperature drift, supports more stringent ambient temperatures, and obtains a more ideal signal-to-noise ratio.

[0074] The first shunt resistor and the second shunt resistor are both the same high-precision shunt resistors, refer to Figure 3 , Figure 3 This is the PCB wiring diagram of the Kelvin connection of the high-precision shunt resistor. The high-precision shunt resistor can be used Figure 3 R SH express.

[0075] Figure 3 The Kelvin trace shown is a four-wire connection method used to more accurately measure the current flowing through a high-precision shunt resistor. Figure 3 The two thick lines of "solid arrows" shown are power supply or voltage acquisition lines. The Kelvin trace is set in this application because when the current output by the high-voltage power supply is large, the voltage drop of the current on the power supply line cannot be ignored, and VL=I*RL, where VL refers to the voltage value of the high-voltage power supply flowing through the power supply line and the high-precision shunt resistor, I refers to the current output by the high-voltage power supply, and RL refers to the sum of the line resistance of the power supply line and the resistance of the high-precision shunt resistor. For example, when the line resistance is 1mΩ, a current of 10A will generate 10mV. For high-precision voltage sampling, this voltage value will cause considerable errors, so the voltage acquisition line set in this application needs to avoid the main current loop, so the line is selected from the inside of the shunt resistor pad.

[0076] For example, the current output by the high voltage power supply flows through the high precision shunt resistor R SH , high precision shunt resistor R SH The resistance value is determined according to the actual maximum load current IMAX and the leakage accuracy to be detected, so that the high-precision shunt resistor R SH The weak voltage Vshunt generated at both ends meets the input voltage range VFSR of the isolation amplifier, where Vshunt = Rshunt*IMAX, and the principle is |Vshunt|≤|VFSR|, but it should be as close to VFSR as possible to maximize the use of the linear amplification range of the post-stage amplifier; the selection parameters of the high-precision shunt resistor set in this application should also pay attention to the temperature drift, because the heat generated by the resistor is considerable when the current is large, and the temperature drift will affect the resistor accuracy, so try to choose a high-precision shunt resistor with a small resistance and a small temperature drift. By using a high-precision shunt resistor with a small resistance and a small temperature drift to measure the current output by the high-voltage power supply, it has high accuracy, saves space, has low cost, has good linearity, and has no zero point offset problem. It is particularly suitable for detecting circuits with high voltage but not large current (for example, a DC voltage of 600V and an operating current of less than 10A).

[0077] Further, in some other feasible embodiments, referring to Figure 4 , Figure 4It is a circuit diagram of the high-voltage leakage protection circuit of the present application; the high-side voltage isolation unit 101 includes a first resistor R1, a second resistor R2, a first capacitor C1 and a first isolation amplifier U1; the first end of the first resistor R1 is electrically connected to one of the two end pads of the first shunt resistor, and the first end of the second resistor R2 is electrically connected to the other end pad of the two end pads of the first shunt resistor; the second end of the first resistor R1 is electrically connected to the first end of the first capacitor C1 and the first end of the first isolation amplifier U1, respectively, and the second end of the second resistor R2 is electrically connected to the second end of the first capacitor C1 and the second end of the first isolation amplifier U1, respectively; the third end of the first isolation amplifier U1 constitutes the high-side power supply end of the high-side voltage isolation unit 101 and is electrically connected to the signal sampling end of the analog-to-digital conversion module 20.

[0078] In this embodiment, refer to Figure 4 , Figure 4 The first resistor R1, the second resistor R2, and the first capacitor C1 shown constitute an analog filtering circuit in the high-side voltage isolation unit 101, which is used to filter the high-side voltage signal collected through the two-end pads of the first shunt resistor to remove noise and interference and improve the stability and reliability of the high-side voltage signal.

[0079] Further, in some feasible embodiments, referring to Figure 4 The low-side voltage isolation unit 102 includes a third resistor R3, a fourth resistor R4, a second capacitor C2 and a second isolation amplifier U2; the first end of the third resistor R3 is electrically connected to one of the two end pads of the second shunt resistor, and the first end of the fourth resistor R4 is electrically connected to the other end pad of the two end pads of the second shunt resistor; the second end of the third resistor R3 is electrically connected to the first end of the second capacitor C2 and the first end of the second isolation amplifier U2 respectively, and the second end of the fourth resistor R4 is electrically connected to the second end of the second capacitor C2 and the second end of the second isolation amplifier U2 respectively; the third end of the second isolation amplifier U2 constitutes the low-side power supply end of the low-side voltage isolation unit 102 and is electrically connected to the signal sampling end of the analog-to-digital conversion module 20.

[0080] In this embodiment, refer to Figure 4 , Figure 4 The third resistor R3, the fourth resistor R4 and the second capacitor C2 shown constitute an analog filtering circuit in the high-side voltage isolation unit 101, which is used to filter the low-side voltage signal collected through the two end pads of the second shunt resistor to remove noise and interference and improve the stability and reliability of the low-side voltage signal.

[0081] Further, in some other feasible embodiments, the analog-to-digital conversion module 20 includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a third capacitor C3, a fourth capacitor C4 and a differential input component A1; the first end of the fifth resistor R5 and the first end of the sixth resistor R6 constitute a high-side sampling interface in the signal sampling end, which is electrically connected to the high-side interface in the sampling output end; the first end of the seventh resistor R7 and the first end of the eighth resistor R8 constitute a low-side sampling interface in the signal sampling end, which is electrically connected to the low-side interface in the sampling output end; the first end of the third capacitor C3 is respectively connected to the second end of the fifth resistor R5 The first end of the fourth capacitor C4 is electrically connected to the second end of the seventh resistor R7 and the low-side negative pin of the differential input component A1, and the second end of the fourth capacitor C4 is electrically connected to the second end of the eighth resistor R8 and the low-side positive pin of the differential input component A1; the data interface of the differential input component A1 constitutes a data output end of the analog-to-digital conversion module 20 and is electrically connected to the signal input end of the leakage detection module 30.

[0082] In this embodiment, refer to Figure 4 , an analog input channel formed by the high-side positive pin (i.e., AIN1P) and the high-side negative pin (i.e., AIN1N) of the differential input component A1 receives the high-side analog signal from the high-side isolation amplifier, and at the same time, another analog input channel formed by the low-side positive pin (i.e., AIN2P) and the low-side negative pin (i.e., AIN2N) of the differential input component A1 receives the low-side analog signal from the low-side isolation amplifier, thereby realizing that the two analog input channels of the differential input component A1 are respectively connected to the outputs of the high-side voltage isolation unit 101 and the low-side voltage isolation unit 102, so that the high-side analog signal from the high-side isolation amplifier and the low-side analog signal from the low-side isolation amplifier can be synchronously collected; next, the high-side analog signal and the low-side analog signal are respectively converted into high-side digital signals and low-side digital signals and transmitted to the leakage detection module 30, thereby providing reliable and effective data support for the leakage detection module 30 connected in series between the high-side high-voltage power supply line H1 / the low-side high-voltage power supply line L1 and the load.

[0083] It should be noted that the differential input component A1 can be understood as an analog-to-digital converter chip (ADC), and the analog-to-digital converter chip set in this application uses a (≥24bit) dual-channel synchronous sampling ΔΣ type ADC, and the analog input channel adopts a differential form. The analog-to-digital converter chip adopts a differential input channel to well suppress common-mode interference signals. The differential voltage range and single-ended voltage range to ground of the input analog signal should be greater than and as close as possible to the output voltage range of the isolation amplifier, and the input dynamic range of the ADC sampling should be fully utilized.

[0084] In summary, the analog-to-digital conversion module 20 uses a high-resolution, synchronously sampled ADC, which has a higher effective resolution and a larger input voltage range than an isolated ADC, so that the final sampling accuracy is higher.

[0085] Further, in some feasible embodiments, referring to Figure 2 The leakage detection module 30 includes a control unit 301, a positive leakage protection unit 302 and a negative leakage protection unit 303; the analog-to-digital conversion interface of the control unit 301 constitutes a signal input end of the leakage detection module 30 and is electrically connected to the data output end of the analog-to-digital conversion module 20, and the control interface of the control unit 301 is electrically connected to the positive leakage protection unit 302 and the negative leakage protection unit 303 respectively; the positive leakage protection unit 302 is connected in series between the high-side high-voltage power supply line H1 and the load, and the negative leakage protection unit 303 is connected in series between the low-side high-voltage power supply line L1 and the load.

[0086] In this embodiment, the control unit 301 provided in the present application can configure the differential input component A1 so that it can work normally, so that the high-side digital signal and the low-side digital signal output by the analog-to-digital conversion of the differential input component A1 can be accurately collected. Next, after subtracting the high-side digital signal and the low-side digital signal, the subtraction result is converted into a leakage current value of the power supply circuit from the high-voltage power supply to the load. Next, a threshold comparison is performed based on the leakage current value and the preset leakage threshold, and the data processing result can be accurately obtained. According to the data processing result, the corresponding level control signal is output to synchronously control the positive leakage protection unit 302 and the negative leakage protection unit 303 to perform effective leakage protection, thereby significantly improving the response speed and reliability of leakage detection, avoiding load equipment failures, data errors, and safety accidents such as fire and electric shock caused by leakage of the high-voltage DC power supply line, and ensuring the safety of users' electricity use.

[0087] It should be noted that the control unit 301 can be understood as a field programmable gate array (FPGA), which has the advantages of low latency and parallel processing, can quickly respond to leakage events, and can quickly control the positive leakage protection unit 302 and the negative leakage protection unit 303 to perform effective leakage protection.

[0088] Exemplarily, after the high-side digital signal and the low-side digital signal obtained from the dual channels of the differential input component A1 by the control unit 301 provided in the present application enter the cache area in the control unit 301, the data difference between the high-side digital signal and the low-side digital signal is converted into a leakage current value according to the resistance difference between the first shunt resistor and the first shunt resistor, and then compared with the preset leakage threshold (such as 1mA) and output a corresponding level control signal, so that the positive leakage protection unit 302 and the negative leakage protection unit 303 can be quickly controlled to perform effective leakage protection.

[0089] Further, in some other feasible embodiments, the positive leakage protection unit 302 includes a first optical isolation driver U3 and a first switch tube Q1, and the negative leakage protection unit 303 includes a second optical isolation driver U4 and a second switch tube Q2; the anode end of the first optical isolation driver U3 and the anode end of the second optical isolation driver U4 are respectively electrically connected to the control interface of the control unit 301, and the cathode end of the first optical isolation driver U3 and the cathode end of the second optical isolation driver U4 are respectively grounded; the first channel end of the first switch tube Q1 is electrically connected to the high-side high-voltage power supply line H1, and the second channel end of the first switch tube Q1 is electrically connected to the high-side high-voltage power supply line H1. The first optical isolation driver U3 is electrically connected to the load, the control end of the first switch tube Q1 is electrically connected to the first output end of the first optical isolation driver U3, and the second output end of the first optical isolation driver U3 is electrically connected between the second passage end of the first switch tube Q1 and the load; the first passage end of the second switch tube Q2 is electrically connected to the low-side high-voltage power supply line L1, the second passage end of the second switch tube Q2 is electrically connected to the load, the control end of the second switch tube Q2 is electrically connected to the first output end of the second optical isolation driver U4, and the second output end of the second optical isolation driver U4 is electrically connected between the second passage end of the second switch tube Q2 and the load.

[0090] In this embodiment, the first optical isolation driver U3 and the second optical isolation driver U4 are both the same optical isolation MOSFET driver, the first switch tube Q1 and the second switch tube Q2 are both the same high-voltage power NMOS tube, and since the output voltage of the optical isolation MOSFET driver must be able to meet the maximum turn-on voltage and switching speed of the NMOS tube, the optical isolation MOSFET driver set in this application is selected to be at the ns (nanosecond) level, the drain-source withstand voltage of the selected NMOS tube must be greater than the high-voltage DC power supply voltage, the drain current capacity must meet the maximum load current, and the on-resistance between the drain and the source must be as small as possible to reduce the heating of the device. The positive leakage protection unit 302 and the negative leakage protection unit 303 set in this application realize the function of the low-voltage side circuit controlling the high-voltage side power supply to quickly disconnect, which not only effectively controls the cost of the high-voltage leakage protection circuit, but also ensures the personal safety of the user. In other words, the combination of optical isolation MOSFET driver + NMOS tube makes the shutdown speed 1 to 2 orders of magnitude faster than the high-voltage relay, the chip size will be smaller, the reliability will be higher, there will be no problem of relay adhesion, and the leakage protection will be more reliable.

[0091] In a specific embodiment, when the leakage current value exceeds a preset leakage threshold, the trigger control unit 301 automatically outputs a level control signal representing a high level to the optically isolated MOSFET driver. After the optically isolated MOSFET driver performs photoelectric conversion on the level control signal representing the high level, the NMOS tube is enabled to switch from the on state to the off state under the action of the level control signal after photoelectric conversion, so as to quickly cut off the electrical connection between the high / low side high-voltage power supply line L1 and the load, thereby realizing the function of the low-voltage side circuit controlling the high-voltage side power supply to quickly disconnect.

[0092] When the leakage current value does not exceed the preset leakage threshold, the trigger control unit 301 automatically outputs a level control signal representing a low level to the optically isolated MOSFET driver. After the optically isolated MOSFET driver performs photoelectric conversion on the level control signal representing the low level, the NMOS tube is enabled to maintain the on state under the action of the level control signal after photoelectric conversion, thereby ensuring that the high-voltage power supply supplies power to the load normally.

[0093] In summary, the present application uses a combination of high-precision shunt resistors and isolation amplifiers that are particularly suitable for current testing of high-voltage, low-current (1000V@10A) lines, and has the advantages of small size, no initial offset, low noise, good linearity, and low cost; the measurement accuracy and ability to resist complex electromagnetic environments are much higher than those of Hall sensors, and the cost and size are lower than those of zero-flux sensors, and it can achieve high-precision isolated current measurement of high-voltage DC signals, greatly improve the measurement sensitivity of power line leakage, and achieve monitoring performance of leakage current <1mA; in addition, the present application uses a high-resolution dual-channel ADC to synchronously sample the positive output current and negative input current at the high-voltage power supply, and calculates the current difference in real time through a programmable logic chip (i.e., FPGA) and quickly executes leakage protection, achieving performance indicators of high leakage detection sensitivity (theoretically <1mA) and fast response.

[0094] Based on the above embodiments of the high-voltage leakage protection circuit, a first embodiment of the leakage detection method of the high-voltage leakage protection circuit of the present application is proposed. The leakage detection method is applied to the above-mentioned high-voltage leakage protection circuit, referring to Figure 5 , Figure 5 It is a flow chart of the first embodiment of the leakage detection method of the high-voltage leakage protection circuit of the present application, and the leakage detection method includes steps S10 to S30.

[0095] Step S10: obtaining a high-side analog signal and a low-side analog signal of the high-voltage power supply through the current acquisition module 10.

[0096] In this embodiment, the current acquisition module 10 is respectively connected in series with the high-side high-voltage power supply line H1 and the low-side high-voltage power supply line L1 of the high-voltage power supply, thereby realizing real-time detection of the output current of the high-voltage power supply, so that the current acquisition module 10 can accurately collect the high-side analog signal generated by the high-voltage power supply on the high-side high-voltage power supply line H1 and the low-side analog signal generated by the high-voltage power supply on the low-side high-voltage power supply line L1 in real time, thereby realizing effective monitoring and acquisition of the current.

[0097] Step S20: converting the high-side analog signal and the low-side analog signal sent by the current acquisition module 10 into high-side digital signals and low-side digital signals respectively through the analog-to-digital conversion module 20 .

[0098] In this embodiment, the signal sampling end of the analog-to-digital conversion module 20 provided in the present application is composed of two analog input channels consisting of a high-side sampling interface and a low-side sampling interface, which are electrically connected to the high-side interface and the low-side interface in the sampling output end respectively, so that the high-side analog signal converted and conditioned from the first shunt resistor on the high-side high-voltage power supply line H1 of the high-voltage power supply, and the low-side analog signal converted and conditioned from the second shunt resistor on the low-side high-voltage power supply line L1 of the high-voltage power supply can be collected simultaneously, and the high-side analog signal and the low-side analog signal are converted into high-side digital signals and low-side digital signals respectively, and then transmitted to the leakage detection module 30, thereby providing reliable and effective data support for the leakage detection module 30 connected in series between the high-side high-voltage power supply line H1 / low-side high-voltage power supply line L1 and the load.

[0099] Step S30: Receive the high-side digital signal and the low-side digital signal output by the analog-to-digital conversion module 20 through the leakage detection module 30, and determine the leakage current value according to the high-side digital signal and the low-side digital signal, determine the leakage protection signal according to the leakage current value and a preset leakage threshold, and perform leakage protection according to the leakage protection signal.

[0100] In this embodiment, according to the electrical connection between the signal input terminal of the leakage detection module 30 and the data output terminal of the analog-to-digital conversion module 20, after the control unit 301 in the leakage detection module 30 receives the high-side digital signal and the low-side digital signal sent by the analog-to-digital conversion module 20, the high-side current value can be accurately calculated according to the high-side digital signal and the resistance value of the first shunt resistor, and the low-side current value can be accurately calculated according to the low-side digital signal and the resistance value of the second shunt resistor, and the leakage current value of the power supply circuit from the high-voltage power supply to the load can be efficiently and accurately calculated according to the difference between the high-side current value and the low-side current value; next, it is determined whether the leakage current value exceeds the preset leakage threshold value, and if the leakage current value exceeds the preset leakage threshold value, the triggering The control unit 301 automatically outputs a leakage protection signal to the positive leakage protection unit 302 and the negative leakage protection unit 303 in the leakage detection module 30 at the same time, so that the positive leakage protection unit 302 and the negative leakage protection unit 303 synchronously respond to the leakage protection signal, so as to immediately cut off the electrical connection between the high-side high-voltage power supply line H1 and the load, and the electrical connection between the low-side high-voltage power supply line L1 and the load, thereby significantly improving the response speed and reliability of leakage detection, so that the power supply circuit from the high-voltage power supply to the load can be quickly disconnected in the event of leakage of the high-voltage DC power supply line, avoiding load equipment failure, data error, fire, electric shock and other safety accidents caused by leakage of the high-voltage DC power supply line, thereby ensuring the user's power safety.

[0101] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the leakage detection method of the high-voltage leakage protection circuit of the present application. More simple transformations based on this technical concept are all within the protection scope of the present application.

[0102] In addition, this application also provides a leakage protection system. Figure 6 , Figure 6 The schematic diagram of the structure of the leakage protection system involved in the embodiment of the present application is shown in FIG. The leakage protection system in the embodiment of the present application may be a device for locally running a leakage detection program of a high-voltage leakage protection circuit.

[0103] The present application provides a leakage protection system, which includes: at least one processor; and a memory connected to the at least one processor in communication; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the leakage detection method of the high-voltage leakage protection circuit in the above-mentioned embodiment one.

[0104] Reference below Figure 6 , which shows a schematic diagram of the structure of the leakage protection system suitable for implementing the embodiment of the present application. The leakage protection system in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 6 The leakage protection system shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0105] like Figure 6As shown, the leakage protection system may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the leakage protection system are also stored. The processing device 1001, ROM1002, and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input system 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the leakage protection system to communicate with other devices wirelessly or by wire to exchange data. Although the leakage protection system with various systems is shown in the figure, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or have alternatively.

[0106] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0107] The leakage protection system provided by the present application adopts the leakage detection method of the high-voltage leakage protection circuit in the above-mentioned embodiment, which can solve the technical problem of poor reliability of leakage detection of high-voltage DC power supply lines to ensure the safety of electricity use. Compared with the prior art, the beneficial effects of the leakage protection system provided by the present application are the same as the beneficial effects of the leakage detection method of the high-voltage leakage protection circuit provided by the above-mentioned embodiment, and other technical features of the leakage protection system are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0108] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0109] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0110] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the leakage detection method of the high-voltage leakage protection circuit in the above-mentioned embodiment.

[0111] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0112] The computer-readable storage medium may be included in the leakage protection system; or may exist independently without being assembled into the leakage protection system.

[0113] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by the leakage protection system, the leakage protection system:

[0114] Acquire the high-side analog signal and the low-side analog signal of the high-voltage power supply through the current acquisition module 10;

[0115] The high-side analog signal and the low-side analog signal sent by the current acquisition module 10 are converted into high-side digital signals and low-side digital signals respectively by the analog-to-digital conversion module 20;

[0116] The high-side digital signal and the low-side digital signal output by the analog-to-digital conversion module 20 are received through the leakage detection module 30, and a leakage current value is determined based on the high-side digital signal and the low-side digital signal, a leakage protection signal is determined based on the leakage current value and a preset leakage threshold, and leakage protection is performed based on the leakage protection signal.

[0117] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0118] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0119] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0120] The readable storage medium provided by the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the leakage detection method of the above-mentioned high-voltage leakage protection circuit, and can solve the technical problem that the intelligence of computer power on / off control is not high. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the present application are the same as the beneficial effects of the leakage detection method of the high-voltage leakage protection circuit provided by the above-mentioned embodiment, and will not be repeated here.

[0121] The present application also provides a computer program product, including a computer program, which implements the steps of the leakage detection method for the high-voltage leakage protection circuit as described above when the computer program is executed by a processor.

[0122] The computer program product provided by the present application can solve the technical problem of low intelligence in computer power on / off control. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the leakage detection method of the high-voltage leakage protection circuit provided by the above embodiment, which will not be elaborated here.

[0123] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A high voltage leakage protection circuit, characterized in that: The high voltage leakage protection circuit comprises: A current acquisition module, wherein the current acquisition module is connected in series with a high-side high-voltage power supply line and a low-side high-voltage power supply line of the high-voltage power supply, respectively, and the current acquisition module is configured to obtain a high-side analog signal and a low-side analog signal of the high-voltage power supply; An analog-to-digital conversion module, wherein a signal sampling end of the analog-to-digital conversion module is electrically connected to a sampling output end of the current acquisition module, and the analog-to-digital conversion module is configured to convert the high-side analog signal and the low-side analog signal sent by the current acquisition module into high-side digital signals and low-side digital signals respectively; A leakage detection module, wherein the leakage detection module is respectively connected in series between the high-side high-voltage power supply line and the load, and between the low-side high-voltage power supply line and the load, the signal input end of the leakage detection module is electrically connected to the data output end of the analog-to-digital conversion module, and the leakage detection module is configured to receive the high-side digital signal and the low-side digital signal output by the analog-to-digital conversion module, and determine a leakage current value based on the high-side digital signal and the low-side digital signal, determine a leakage protection signal based on the leakage current value and a preset leakage threshold, and perform leakage protection based on the leakage protection signal.

2. The high voltage leakage protection circuit according to claim 1, characterized in that: The current acquisition module includes a first shunt resistor, a second shunt resistor, a high-side voltage isolation unit and a low-side voltage isolation unit; The first shunt resistor is connected in series between the high-side voltage end of the high-voltage power supply and the high-side high-voltage power supply line, and the second shunt resistor is connected in series between the low-side voltage end of the high-voltage power supply and the low-side high-voltage power supply line; The pads at both ends of the first shunt resistor constitute a high-side voltage collection path electrically connected to the voltage input end of the high-side voltage isolation unit, and the pads at both ends of the second shunt resistor constitute a low-side voltage collection path electrically connected to the voltage input end of the low-side voltage isolation unit; The high-side power supply end of the high-side voltage isolation unit constitutes the high-side interface in the sampling output end, and the low-side power supply end of the low-side voltage isolation unit constitutes the low-side interface in the sampling output end, which are electrically connected to the signal sampling end of the analog-to-digital conversion module respectively.

3. The high voltage leakage protection circuit according to claim 2, characterized in that: The high-side voltage isolation unit includes a first resistor, a second resistor, a first capacitor and a first isolation amplifier; The first end of the first resistor is electrically connected to one of the two end pads of the first shunt resistor, and the first end of the second resistor is electrically connected to the other of the two end pads of the first shunt resistor; The second end of the first resistor is electrically connected to the first end of the first capacitor and the first end of the first isolation amplifier respectively, and the second end of the second resistor is electrically connected to the second end of the first capacitor and the second end of the first isolation amplifier respectively; The third terminal of the first isolation amplifier constitutes the high-side power supply terminal of the high-side voltage isolation unit and is electrically connected to the signal sampling terminal of the analog-to-digital conversion module.

4. The high voltage leakage protection circuit according to claim 2, characterized in that: The low-side voltage isolation unit includes a third resistor, a fourth resistor, a second capacitor and a second isolation amplifier; The first end of the third resistor is electrically connected to one of the two end pads of the second shunt resistor, and the first end of the fourth resistor is electrically connected to the other of the two end pads of the second shunt resistor; The second end of the third resistor is electrically connected to the first end of the second capacitor and the first end of the second isolation amplifier respectively, and the second end of the fourth resistor is electrically connected to the second end of the second capacitor and the second end of the second isolation amplifier respectively; The third terminal of the second isolation amplifier constitutes a low-side power supply terminal of the low-side voltage isolation unit and is electrically connected to the signal sampling terminal of the analog-to-digital conversion module.

5. The high voltage leakage protection circuit according to claim 1, characterized in that: The analog-to-digital conversion module includes a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a third capacitor, a fourth capacitor and a differential input component; The first end of the fifth resistor and the first end of the sixth resistor constitute a high-side sampling interface in the signal sampling end, and are electrically connected to the high-side interface in the sampling output end; The first end of the seventh resistor and the first end of the eighth resistor constitute a low-side sampling interface in the signal sampling end, and are electrically connected to the low-side interface in the sampling output end; The first end of the third capacitor is electrically connected to the second end of the fifth resistor and the high-side negative pin of the differential input component, the second end of the third capacitor is electrically connected to the second end of the sixth resistor and the high-side positive pin of the differential input component, the first end of the fourth capacitor is electrically connected to the second end of the seventh resistor and the low-side negative pin of the differential input component, and the second end of the fourth capacitor is electrically connected to the second end of the eighth resistor and the low-side positive pin of the differential input component; The data interface of the differential input component constitutes a data output end of the analog-to-digital conversion module and is electrically connected to the signal input end of the leakage detection module.

6. The high voltage leakage protection circuit according to claim 1, characterized in that: The leakage detection module includes a control unit, a positive leakage protection unit and a negative leakage protection unit; The analog-to-digital conversion interface of the control unit constitutes a signal input end of the leakage detection module and is electrically connected to the data output end of the analog-to-digital conversion module, and the control interface of the control unit is electrically connected to the positive leakage protection unit and the negative leakage protection unit respectively; The positive leakage protection unit is connected in series between the high-side high-voltage power supply line and the load, and the negative leakage protection unit is connected in series between the low-side high-voltage power supply line and the load.

7. The high voltage leakage protection circuit according to claim 6, characterized in that: The positive electrode leakage protection unit includes a first optical isolation driver and a first switch tube, and the negative electrode leakage protection unit includes a second optical isolation driver and a second switch tube; The anode end of the first optical isolation driver and the anode end of the second optical isolation driver are electrically connected to the control interface of the control unit respectively, and the cathode end of the first optical isolation driver and the cathode end of the second optical isolation driver are grounded respectively; The first passage end of the first switch tube is electrically connected to the high-side high-voltage power supply line, the second passage end of the first switch tube is electrically connected to the load, the control end of the first switch tube is electrically connected to the first output end of the first optical isolation driver, and the second output end of the first optical isolation driver is electrically connected between the second passage end of the first switch tube and the load; The first passage end of the second switch tube is electrically connected to the low-side high-voltage power supply line, the second passage end of the second switch tube is electrically connected to the load, the control end of the second switch tube is electrically connected to the first output end of the second optical isolation driver, and the second output end of the second optical isolation driver is electrically connected between the second passage end of the second switch tube and the load.

8. A leakage detection method for a high voltage leakage protection circuit, characterized in that: The leakage detection method is applied to the high-voltage leakage protection circuit according to claims 1 to 7, and the leakage detection method comprises: Acquire the high-side analog signal and low-side analog signal of the high-voltage power supply through the current acquisition module; The high-side analog signal and the low-side analog signal sent by the current acquisition module are converted into high-side digital signals and low-side digital signals respectively through an analog-to-digital conversion module; The high-side digital signal and the low-side digital signal output by the analog-to-digital conversion module are received through the leakage detection module, and the leakage current value is determined according to the high-side digital signal and the low-side digital signal, and the leakage protection signal is determined according to the leakage current value and a preset leakage threshold, and leakage protection is performed according to the leakage protection signal.

9. A protection system, characterized in that: The protection system is a leakage protection system, and the leakage protection system comprises the high-voltage leakage protection circuit according to claims 1 to 7; or, The leakage protection system includes a processor, a memory, and a leakage detection program for a high-voltage leakage protection circuit stored in the memory and executable by the processor, wherein when the leakage detection program is executed by the processor, the steps of the leakage detection method as described in claim 8 are implemented.

10. A medium, characterized in that The medium is a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the leakage detection method according to claim 8 are implemented.

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