CN115951207A

CN115951207A - Test circuit and system of solid relay

Info

Publication number: CN115951207A
Application number: CN202211668660.8A
Authority: CN
Inventors: 李奇; 张昭; 李光雄; 王守丰; 陈昭君
Original assignee: BEIJING KEYTONE ELECTRONIC RELAY CORP
Current assignee: BEIJING KEYTONE ELECTRONIC RELAY CORP
Priority date: 2022-12-24
Filing date: 2022-12-24
Publication date: 2023-04-11
Anticipated expiration: 2042-12-24
Also published as: CN115951207B

Abstract

The application provides a test circuit and a system of a solid relay, wherein the test circuit comprises a high-voltage generator, a rectification module, a peak value detection module, a tested device, an electric leakage detection module, a comparison module and a protection module; the high-voltage generator is coupled with the rectifying module, and the rectifying module is coupled with the peak value detection module and the device to be tested; the device to be tested is coupled with the electric leakage detection module, the electric leakage detection module is coupled with the comparison module, and the comparison module is coupled with the protection module; the protection module is also coupled to the high voltage generator. This application is through adopting above-mentioned test circuit and system, and the solution needs artifical wiring or switches test condition in solid relay's parameter testing process for the test procedure makes mistakes easily, and the problem of inefficiency.

Description

Test circuit and system of solid relay

Technical Field

The application relates to the technical field of electronic device detection, in particular to a test circuit and a test system of a solid relay.

Background

The Solid State Relay is also called as a Solid State Relay (SSR) and is composed of a microelectronic circuit, a discrete electronic device and a power electronic power device. The isolation of the control end and the load end is realized by the isolation device. The input end of the solid relay uses a tiny control signal to directly drive a heavy current load. When the solid relay serving as an electronic device is delivered from a factory, various product parameters of the solid relay need to be checked, so that the quality of the product is guaranteed.

At present, when quality detection is carried out on relay products in the market, various different instruments are generally adopted to detect various parameters of the solid relay. For example, a peak voltage withstand voltage test is performed on the solid-state relay using a graphic instrument, an ac withstand voltage test is performed on the solid-state relay using a withstand voltage tester, and insulation resistance detection is performed on the solid-state relay using an insulation resistance meter. In the detection process of the various parameters, manual wiring or test condition switching is required, so that the whole test process is easy to make mistakes and low in efficiency.

Currently, a solid state relay test circuit and system are needed to solve the above problems.

Disclosure of Invention

The application provides a solid relay test circuit and system for solve at the parameter testing process of solid relay, need carry out artifical wiring or switch test condition for the test procedure makes mistakes easily, and the problem of inefficiency.

The first aspect of the application provides a solid relay test circuit, which comprises a high-voltage generator, a rectification module, a peak value detection module, a tested device, an electric leakage detection module, a comparison module and a protection module; the high-voltage generator is coupled with the rectifying module, and the rectifying module is coupled with the peak value detection module and the device to be tested; the device to be tested is coupled with the electric leakage detection module, the electric leakage detection module is coupled with the comparison module, and the comparison module is coupled with the protection module; the protection module is also coupled to the high voltage generator.

This application has realized going on automatically of solid relay testing process through adopting above-mentioned circuit, has avoided the problem that efficiency of software testing is low because of artificial misoperation causes.

Optionally, the leakage detecting module includes: the circuit comprises a first operational amplifier, a second operational amplifier, a first resistor, a first triode, a second triode and a sampling resistor; the negative electrode of the input end of the first operational amplifier is coupled with the tested device, the positive electrode of the input end is grounded, and the output end is simultaneously coupled with one end of the first resistor, the base electrode of the first triode and the base electrode of the second triode; the collector of the first triode is coupled with the positive electrode of the power supply end, and the collector of the second triode is coupled with the negative electrode of the power supply end; the positive electrode of the input end of the second operational amplifier is coupled with the emitting electrode of the first triode, the emitting electrode of the second triode and the other end of the first resistor, the negative electrode of the input end of the second operational amplifier is coupled with the negative electrode of the input end of the first operational amplifier, and the output end of the second operational amplifier is coupled with the comparison module; the sampling resistor is connected in parallel with the input end of the second operational amplifier.

This application is through adopting above-mentioned electric leakage detection module, samples the leakage current, and the current signal who will leak the current through IVC converting circuit converts voltage signal into.

Optionally, the comparing module includes: a third operational amplifier, a second resistor, a third resistor, a fourth resistor, a varistor, a first capacitor, and a latch; the anode of the input end of the third operational amplifier is coupled with the leakage detection module, the cathode of the input end of the third operational amplifier is coupled with one end of a third resistor, and the other end of the third resistor is grounded; one end of the rheostat is coupled with the power supply end, and the other end of the rheostat is coupled with the negative electrode of the input end of the third operational amplifier; one end of the second resistor is coupled with the power supply end, the other end of the second resistor is coupled with the output end of the third operational amplifier, and the second resistor is also connected with the first capacitor in parallel; one end of the fourth resistor is coupled with the output end of the third operational amplifier, and the other end of the fourth resistor is coupled with the CLR port of the latch; the CLK port of the latch is used for receiving a reset signal, and the output end of the latch is coupled with the protection module.

By adopting the comparison module, the voltage signals in the output comparison module are compared, so that the latch is controlled to be turned off, and the action control of the protection module is realized by turning off the latch.

Optionally, the protection module includes: the resistor comprises a fifth resistor, a sixth resistor, a seventh resistor, a first diode, a field effect tube and a relay; one end of the seventh resistor is coupled with the comparison module, and the other end of the seventh resistor is coupled with the base electrode of the field effect transistor; the emitter of the field effect transistor is grounded, and the collector is coupled with one end of the relay; the other end of the relay is coupled with one end of a sixth resistor, and the other end of the sixth resistor is connected with the power supply end; the two ends of a control switch of the relay are coupled with the high-voltage generator, and the control switch is used for controlling the turn-off of the high-voltage generator. The negative electrode of the first diode is coupled with the collector of the field effect transistor, and the positive electrode of the first diode is coupled with one end of the fifth resistor; the other end of the fifth resistor is coupled to one end of the sixth resistor.

This application is through adopting above-mentioned protection module, under the effect that protection module combines comparison module, when comparison module judges that voltage signal is too big, when the leakage current is greater than the setting value in the test loop promptly, protection module action for the disconnection of high voltage generator avoids in solid relay's test procedure, because the leakage current is too big, and high voltage continuously exerts on being surveyed the device, and causes being surveyed the further damage of device.

Optionally, the first operational amplifier and the second operational amplifier are low-distortion operational amplifiers, and a ratio of a leakage current of the low-distortion operational amplifier to a leakage current of the device under test is smaller than a preset ratio.

By adopting the operational amplifier, the test accuracy is improved because the leakage current in the test loop is small and the operational amplifier with small leakage current is selected in the test process of the solid relay.

Optionally, the third operational amplifier is a high-speed comparison amplifier, and the response time of the high-speed operational amplifier is less than a predetermined time.

By adopting the comparison amplifier, the response time of the protection module is prolonged in the test process of the solid relay, and the damage to the tested device caused by the rapid increase of the current is prevented.

Optionally, the rectifying module includes: a second diode and an eighth resistor; the anode of the second diode is coupled with the high-voltage generator, and the cathode of the second diode is coupled with one end of an eighth resistor R8; the other end of the eighth resistor is coupled to the device under test.

Optionally, the peak detection module is configured to receive a peak voltage sent by the rectification unit, and detect the peak voltage; the peak detection module is further used for converting the peak voltage into a direct current voltage so that the direct current voltmeter can display the peak voltage conveniently.

A second aspect of the present application provides a solid state relay test system, which includes any one of the above circuits, a controller, a relay switching module, and an output interface; the controller is coupled with any circuit and is also coupled with the relay switching module; the relay switching module is coupled with the output interface.

This application is through adopting above-mentioned solid relay test system, through the multiplexed output interface that can extend, realizes the automatic switch-over in the multichannel solid relay test process.

Optionally, the relay switching module includes a first switching unit and a second switching unit, and the output interface includes a first output interface and a second output interface; the first switching unit is coupled with the first output interface; the second switching unit is coupled with the second output interface.

Compared with the related art, the beneficial effects of this application are: the automatic detection of the solid relay is realized, the problem of low testing efficiency caused by manual misoperation is avoided, and the testing speed is increased. The test circuit can trigger protection when the test result of the tested device is unqualified, and cut off high-voltage output in time to prevent further damage to the tested device. In addition, this application can also realize the automatic switch-over when testing multichannel solid state relay, avoids the artificial operation such as carrying out the wiring and the trouble that causes.

Drawings

Fig. 1 is a schematic structural diagram of a solid-state relay test circuit provided in an embodiment of the present application;

fig. 2 is a schematic circuit structure diagram of a solid-state relay test circuit provided in an embodiment of the present application;

fig. 3 is a schematic circuit structure diagram of another solid-state relay test circuit provided in the embodiment of the present application;

fig. 4 is a schematic structural diagram of a solid-state relay testing system according to an embodiment of the present application.

Reference numerals: 1. a test circuit; 2. a controller; 3. a relay switching module; 4. an output interface; 11. a high voltage generator; 12. a rectification module; 13. a device under test; 14. a leakage detection module; 15. a comparison module; 16. a protection module; 17. a peak detection module; r1, a first resistor; r2 and a second resistor; r3, a third resistor; r4 and a fourth resistor; r5 and a fifth resistor; r6 and a sixth resistor; r7 and a seventh resistor; rs, a sampling resistor; rp, rheostat; d1, a first diode; d2, a second diode; q1, a first triode; q2 and a second triode; q3, a field effect tube; u1, a first operational amplifier; u2, a second operational amplifier; u3, a third operational amplifier; SQ, latch; JK. A relay.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present specification, the technical solutions in the embodiments of the present specification will be clearly and completely described below with reference to the drawings in the embodiments of the present specification, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments.

In the description of the embodiments of the present application, the words "exemplary," "for example," or "for instance" are used to indicate instances, or illustrations. Any embodiment or design described herein as "exemplary," "e.g.," or "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the words "exemplary," "such as," or "for example" are intended to present relevant concepts in a concrete fashion.

In the description of the embodiments of the present application, the term "and/or" is only one kind of association relationship describing an associated object, and means that three relationships may exist, for example, a and/or B may mean: a exists alone, B exists alone, and A and B exist at the same time. In addition, the term "plurality" means two or more unless otherwise specified. For example, the plurality of systems refers to two or more systems, and the plurality of screen terminals refers to two or more screen terminals. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit indication of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless otherwise specifically stated.

The solid relay test circuit in the embodiment of the application can be applied to an automatic insulation withstand voltage test system of the solid relay. On the basis of traditional direct-current voltage resistance, alternating-current voltage resistance and insulation test, automatic insulation voltage resistance test is realized through a hardware system, test conditions are automatically converted according to set conditions, test results are automatically judged, one-key test and unattended test are realized, peak voltage test and overcurrent protection functions are added, and therefore the traditional graphic instrument and an insulation meter are replaced. The manual wiring and manual switching links are removed in the test, the manual error probability is reduced, and the production efficiency and the productivity are improved.

The embodiment of the application provides a solid relay test circuit. As shown in fig. 1, the circuit includes a high voltage generator 11, a rectifying module 12, a device under test 13, a leakage detecting module 14, a comparing module 15, a protecting module 16, and a peak detecting module 17; the high voltage generator 11 is coupled to the rectifying module 12, and the rectifying module 12 is coupled to the peak detecting module 17 and the device under test 13; the device under test 13 is coupled to the leakage detection module 14, the leakage detection module 14 is coupled to the comparison module 15, and the comparison module 15 is coupled to the protection module 16; the protection module 16 is also coupled to the high voltage generator 11.

In a possible implementation, the peak detection module 17 is configured to receive a peak voltage emitted by the rectification unit 12 and detect the peak voltage; the peak detection module 17 is further configured to convert the peak voltage into a dc voltage, so that the external dc voltmeter can display the peak voltage conveniently.

For example, in the embodiment of the present application, the high voltage generator 11 may be purchased or designed autonomously according to actual requirements, and the output waveform of the high voltage generator 11 is an ac sine wave, and the output amplitude may be set according to the test condition. The high voltage generator 11 outputs the peak voltage Vpk through the rectifying unit 12, and the peak voltage is directly applied to one end of the device under test 13, the other end of the device under test is connected to the leakage current detecting module 14, the leakage current value of the loop is tested, and the leakage current value is converted into a corresponding voltage value through the IVC converting circuit in the leakage current detecting module 14. Overcurrent protection with a threshold of 1mA is realized by the comparison module 15 and the protection module 16. The overcurrent protection adopts hardware protection and software protection at the same time, the hardware protection directly closes the output of the high-voltage generator 11, meanwhile, the protection signal is transmitted to the control end of the test system, and the control end closes the high-voltage generator 11 through software control. The peak detection module 11 realizes peak detection of peak voltage, converts the peak voltage into direct current voltage through a peak detection + latch circuit, and outputs the direct current voltage to a direct current voltmeter to directly display the peak voltage; and simultaneously, the direct current voltage value is also transmitted to the control end. This application can also realize peak voltage's collection through external host computer. The peak detection module 11 in the embodiment of the present application may adopt a conventional peak detection circuit, and the embodiment of the present application may replace and change the peak detection circuit according to different requirements, which is not expanded in detail herein.

In one possible implementation, as shown in fig. 2, the leakage detecting module 14 includes: the circuit comprises a first operational amplifier U1, a second operational amplifier U2, a first resistor R1, a first triode Q1, a second triode Q2 and a sampling resistor Rs; the negative electrode of the input end of the first operational amplifier U1 is coupled with a device to be tested, the positive electrode of the input end is grounded, and the output end is simultaneously coupled with one end of the first resistor R1, the base electrode of the first triode Q1 and the base electrode of the second triode Q2; the collector of the first triode Q1 is coupled with the positive electrode of the power supply end, and the collector of the second triode Q2 is coupled with the negative electrode of the power supply end; the positive electrode of the input end of the second operational amplifier U2 is coupled with the emitting electrode of the first triode Q1, the emitting electrode of the second triode Q2 and the other end of the first resistor R1, the negative electrode of the input end of the second operational amplifier U2 is coupled with the negative electrode of the input end of the first operational amplifier U1, and the output end of the second operational amplifier U2 is coupled with the comparison module 15; the sampling resistor Rs is connected in parallel to the input terminal of the second operational amplifier U2.

In the embodiment of the present application, the circuit principle of the electric leakage detection module 14 is as follows: as shown in fig. 2, after the high voltage generator 11 is operated, a sinusoidal voltage is generated and subjected to half-wave rectification processing by the rectification module 12. The current-limiting power consumption resistor, which is the function of the eighth resistor R8, is used to prevent the peak voltage output power from being too large, so that the ground is short-circuited. The 'virtual short' characteristic of the operational amplifier U1 enables the voltage at the connection between the device under test 13 and the positive electrode of the input end of the first operational amplifier U1 to be the same as the ground, meanwhile, after the output peak voltage is applied to one end of the device under test 13 close to the first operational amplifier U1, the generated leakage current is converted into voltage through the sampling resistor Rs, and after the voltage is amplified by multiple times through the operational amplifier U2, the voltage is converted into a voltage signal which is transmitted to the comparison module 15. In the embodiment of the present application, the first transistor Q1 and the second transistor Q2 play a role of current expansion.

Preferably, the amplification factor of the second operational amplifier U2 may be 5 times.

In one possible embodiment, as shown in fig. 3, the comparison module 15 comprises: a third operational amplifier U3, a second resistor R2, a third resistor R3, a fourth resistor R4, a varistor Rp, a first capacitor C1, and a latch SQ; the positive electrode of the input end of the third operational amplifier U3 is coupled to the leakage detection module 14, the negative electrode of the input end is coupled to one end of the third resistor R3, and the other end of the third resistor R3 is grounded; one end of the rheostat Rp is coupled with the power supply end, and the other end of the rheostat Rp is coupled with the negative electrode of the input end of the third operational amplifier U3; one end of the second resistor R2 is coupled with the power supply end, the other end of the second resistor R2 is coupled with the output end of the third operational amplifier U3, and the second resistor R2 is also connected with the first capacitor in parallel; one end of the fourth resistor R4 is coupled to the output end of the third operational amplifier U3, and the other end is coupled to the CLR port of the latch SQ; the CLK port of latch SQ is used to receive a reset signal and the output of latch SQ is coupled to protection module 16.

In one possible embodiment, as shown in fig. 3, the protection module 16 comprises: a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a first diode D1, a field effect transistor Q3 and a relay JK; one end of the seventh resistor R7 is coupled with the comparison module 15, and the other end is coupled with the base of the field effect transistor Q3; the emitter of the field effect transistor Q3 is grounded, and the collector is coupled with one end of the relay JK; the other end of the relay JK is coupled with one end of a sixth resistor R6, and the other end of the sixth resistor R6 is connected with the power supply end; both ends of a control switch of the relay are coupled with the high voltage generator 11, and the control switch is used for controlling the turn-off of the high voltage generator 11. The negative electrode of the first diode D1 is coupled with the collector electrode of the field effect transistor Q3, and the positive electrode of the first diode D1 is coupled with one end of a fifth resistor R5; the other end of the fifth resistor R5 is coupled to one end of the sixth resistor R6.

The voltage signal output by the leakage detection module 14 is input into the third operational amplifier U3, the input voltage signal of the negative terminal of the input terminal of the third operational amplifier U3 is adjusted by the rheostat Rp, when the voltage signal output by the leakage detection module 14 is lower than the input voltage signal of the negative terminal of the input terminal of the operational amplifier U3, the output terminal of the third operational amplifier U3 outputs a low level, the latch SQ outputs a low level, the field effect transistor Q3 is in a cut-off state, the relay JK is in a cut-off state, the first diode D1 is in a quenched state, at this time, the high voltage generator normally outputs, the test system normally works, when the voltage signal output by the leakage detection module 14 is higher than the input voltage signal of the negative terminal of the operational amplifier U3, the output terminal of the third operational amplifier U3 outputs a high level, at the latch SQ is triggered to output as a high level signal, the field effect transistor Q3 is in a conduction state, the relay JK is in a closed state, at the same time, the first diode D1 is in a lit state, at this time, the output of the high voltage generator is disconnected through the contact of the relay SQ, and an overcurrent protection effect is not allowed. The latch SQ needs to be RESET by a RESET signal RESET. The RESET signal RESET is implemented by a RESET circuit, which is not described herein. The sixth resistor R6 is a voltage dependent resistor and is in a conducting state during normal operation, when the sixth resistor R6 receives external pressure and exceeds a certain threshold value, the resistance characteristic of the sixth resistor R6 is increased along with the increase of the received external pressure, the current of the branch where the sixth resistor R6 is located is reduced, and when the current of the branch is reduced to conducting current, the branch where the sixth resistor R6 is located is cut off. The first diode D1 in the embodiment of the present application may be a light emitting diode.

In one possible implementation, the first operational amplifier U1 and the second operational amplifier U2 are low distortion operational amplifiers, and the ratio of the leakage current of the low distortion operational amplifiers to the detected leakage current of the device under test 13 is smaller than a preset ratio.

In one possible embodiment, the third operational amplifier U3 is a high speed comparison amplifier, the response time of which is less than a predetermined time.

For example, the selection of operational amplifiers in the leakage detection module 14 requires low noise and low input bias current. Wherein the bias current is less than 100pA; preferably, the model of the operational amplifier is selected to be OPA604. The response time of the third operational amplifier U3 in the comparison module 15 is as fast as possible, and is required to be within 10 ns. Preferably, the model of the third operational amplifier may be TLV3502.

In one possible embodiment, as shown in fig. 3, the rectifier module 12 comprises: a second diode D2 and an eighth resistor R8; the anode of the second diode D2 is coupled to the high voltage generator 11, and the cathode is coupled to one end of the eighth resistor R8; the other end of the eighth resistor R8 is coupled to the device under test 13.

The embodiment of the application provides a solid-state relay testing system, as shown in fig. 4, the system includes any one of the above circuits 1, a controller 2, a relay switching module 3, and an output interface 4; the controller 2 is coupled with any one of the circuits 1 and is coupled with the relay switching module 3; the relay switching module 2 is coupled 4 to the output interface.

In a possible embodiment, the relay switching module 3 comprises a first switching unit and a second switching unit, and the output interface 4 comprises a first output interface and a second output interface; the first switching unit is coupled with the first output interface; the second switching unit is coupled with the second output interface.

The test system can control the test circuit by externally connecting the upper computer and the lower computer and combining the communication module. The testing system supports 16-path product testing at maximum by adopting a fully-open software architecture, and each path supports independent programming. And after the test system tests, the system detects the test result, the next test is carried out when the test is passed, and the test is terminated when the test is not passed. The system can implement functions including: automatic withstand voltage test, automatic insulation resistance test, 1mA overcurrent protection and peak voltage display.

The beneficial effects of the embodiment of the application are that: the automatic detection of the solid relay is realized, and the problem of low testing efficiency caused by manual misoperation is avoided. The test circuit can trigger protection when the test result of the tested device is unqualified, and cut off high-voltage output in time to prevent further damage to the tested device. In addition, this application can also realize the automatic switch-over when testing multichannel solid state relay, avoids the artificial trouble that causes of operations such as carrying out the wiring.

It should be noted that: in the test system provided in the above embodiment, when the functions of the test system are implemented, only the division of the functional modules is illustrated, and in practical applications, the functions may be allocated by different functional modules as needed, that is, the internal structure of the test system may be divided into different functional modules to implement all or part of the functions described above.

While, for purposes of simplicity of explanation, the foregoing embodiments have been described as a series of acts or combination of acts, it will be appreciated by those skilled in the art that the present application is not limited by the order of acts or acts described, as some steps may occur in other orders or concurrently with other steps depending upon the application. Further, those skilled in the art should also appreciate that the embodiments described in the specification are preferred embodiments and that the acts and modules referred to are not necessarily required for this application.

In the foregoing embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one type of logical functional division, and other divisions may be realized in practice, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection of some service interfaces, devices or units, and may be an electrical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable memory. Based on such understanding, the technical solution of the present application may be substantially implemented or a part of or all or part of the technical solution contributing to the prior art may be embodied in the form of a software product stored in a memory, and including several instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method described in the embodiments of the present application. And the aforementioned memory comprises: various media capable of storing program codes, such as a U disk, a removable hard disk, a magnetic disk, or an optical disk.

The above description is only an exemplary embodiment of the present disclosure, and the scope of the present disclosure should not be limited thereby. That is, all equivalent changes and modifications made in accordance with the teachings of the present disclosure are intended to be included within the scope of the present disclosure. Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains.

Claims

1. The test circuit of the solid relay is characterized by comprising a high-voltage generator (11), a rectifying module (12), a tested device (13), a leakage detection module (14), a comparison module (15), a protection module (16) and a peak value detection module (17);

the high voltage generator (11) is coupled to the rectifier module (12), the rectifier module (12) is coupled to the peak detection module (17) and to the device under test (13);

the device under test (13) is coupled with the leakage detection module (14), the leakage detection module (14) is coupled with the comparison module (15), the comparison module (15) is coupled with the protection module (16);

the protection module (16) is also coupled to the high voltage generator (11).

2. The circuit according to claim 1, characterized in that the leakage detection module (14) comprises: the circuit comprises a first operational amplifier (U1), a second operational amplifier (U2), a first resistor (R1), a first triode (Q1), a second triode (Q2) and a sampling resistor (Rs);

the negative electrode of the input end of the first operational amplifier (U1) is coupled with the device to be tested, the positive electrode of the input end is grounded, and the output end is simultaneously coupled with one end of the first resistor (R1), the base electrode of a first triode (Q1) and the base electrode of a second triode (Q2);

the collector of the first triode (Q1) is coupled with the positive electrode of a power supply end, and the collector of the second triode (Q2) is coupled with the negative electrode of the power supply end;

the positive terminal of the input end of the second operational amplifier (U2) is coupled with the emitting electrode of the first triode (Q1), the emitting electrode of the second triode (Q2) and the other end of the first resistor (R1), the negative terminal of the input end of the second operational amplifier (U2) is coupled with the negative terminal of the input end of the first operational amplifier (U1), and the output end of the second operational amplifier (U2) is coupled with the comparison module (15);

the sampling resistor (Rs) is connected in parallel with the input end of the second operational amplifier (U2).

3. The circuit according to claim 1, characterized in that the comparison module (15) comprises:

a third operational amplifier (U3), a second resistor (R2), a third resistor (R3), a fourth resistor (R4), a varistor (Rp), a first capacitance (C1), and a latch (SQ);

the positive terminal of the input end of the third operational amplifier (U3) is coupled with the leakage detection module (14), the negative terminal of the input end is coupled with one end of the third resistor (R3), and the other end of the third resistor (R3) is grounded;

one end of the rheostat (Rp) is coupled with a power supply end, and the other end of the rheostat (Rp) is coupled with the negative electrode of the input end of the third operational amplifier (U3);

one end of the second resistor (R2) is coupled with a power supply end, the other end of the second resistor is coupled with the output end of the third operational amplifier (U3), and the second resistor (R2) is also connected with the first capacitor in parallel;

-one end of said fourth resistor (R4) is coupled to the output of said third operational amplifier (U3) and the other end is coupled to the CLR port of said latch (SQ);

the CLK port of the latch (SQ) is adapted to receive a reset signal, and the output of the latch (SQ) is coupled to the protection module (16).

4. The circuit according to claim 1, characterized in that the protection module (16) comprises: a fifth resistor (R5), a sixth resistor (R6), a seventh resistor (R7), a first diode (D1), a field effect transistor (Q3), and a relay (JK);

one end of the seventh resistor (R7) is coupled with the comparison module (15), and the other end is coupled with the base electrode of the field effect transistor (Q3);

the emitter of the field effect transistor (Q3) is grounded, and the collector is coupled with one end of the relay (JK);

the other end of the relay (JK) is coupled with one end of the sixth resistor (R6), and the other end of the sixth resistor (R6) is connected with a power supply end;

two ends of a control switch of the relay are coupled with the high-voltage generator (11), and the control switch is used for controlling the high-voltage generator (11) to be switched off;

the negative electrode of the first secondary tube (D1) is coupled with the collector electrode of the field effect tube (Q3), and the positive electrode of the first secondary tube is coupled with one end of the fifth resistor (R5);

the other end of the fifth resistor (R5) is coupled with one end of the sixth resistor (R6).

5. The circuit according to claim 2, wherein the first operational amplifier (U1) and the second operational amplifier (U2) are low distortion operational amplifiers, and a ratio of a leakage current of the low distortion operational amplifiers to a detected leakage current of the device under test (13) is smaller than a preset ratio.

6. A circuit according to claim 3, characterized in that the third operational amplifier (U3) is a high speed comparison amplifier, the response time of which is less than a predetermined time.

7. The circuit according to claim 1, characterized in that the rectifying module (12) comprises: a second diode (D2) and an eighth resistor (R8);

the anode of the second diode (D2) is coupled to the high voltage generator (11) and the cathode is coupled to one end of the eighth resistor (R8);

the other end of the eighth resistor (R8) is coupled to the device under test (13).

8. The circuit according to claim 1, characterized in that the peak detection module (17) is configured to receive a peak voltage emitted by the rectification unit (12) and detect the peak voltage;

the peak value detection module (17) is also used for converting the peak value voltage into direct current voltage so that a direct current voltmeter can display the peak value voltage.

9. A test system for a solid state relay, the system comprising a circuit according to any one of claims 1 to 8, a controller, a relay switching module, and an output interface;

the controller is coupled with any one of the circuits and is coupled with the relay switching module;

the relay switching module is coupled with the output interface.

10. The system of claim 9, wherein the relay switching module comprises a first switching unit and a second switching unit, the output interface comprising a first output interface and a second output interface;

the first switching unit is coupled with the first output interface;

the second switching unit is coupled with the second output interface.