Solenoid valve electrical performance test system

Abstract

The invention relates to an electrical performance test system, in particular to an electromagnetic valve electrical performance test system. The equipment main control unit comprises a main control computer, and a display and a communication bus module which are connected with the main control computer; the communication bus module comprises an RS232 interface module and a network communication interface module; the test unit comprises a coil resistance test unit, an electrical parameter test unit and a plurality of voltage and current detection units which are connected with the network communication interface module, and a test circuit switching module which is connected with the RS232 interface module and the equipment main control unit; the coil resistance test unit and the electrical parameter test unit are connected with the test circuit switching module. And the voltage and current detection unit and the test circuit switching module are connected with the plurality of electromagnetic valves. Compared with the existing test equipment, different test equipment does not need to be replaced according to different test items, so that the test efficiency is improved, and the labor intensity of workers is reduced.

Description

Technical Field

[0001] This invention relates to electrical performance testing systems, and more specifically to an electrical performance testing system for a solenoid valve. Background Technology

[0002] The electromagnetic valve typical electrical performance testing system is mainly used for electrical performance testing of electromagnetic valves in typical tests. During the test, under the premise of providing accurate and stable power to the electromagnetic valve under test, parameters such as static electrical performance, static response, and dynamic response are tested. The inspection or testing items during the test include coil resistance inspection, insulation resistance inspection, withstand voltage inspection, pull-in voltage and release current testing, response time inspection, and pressure curve testing.

[0003] In previous experiments, the testing equipment used could not meet the requirements of all the above items at the same time, and different testing equipment or devices had to be replaced according to different test items; such testing methods are time-consuming and labor-intensive. Summary of the Invention

[0004] The purpose of this invention is to address the technical problem of the time-consuming and labor-intensive nature of testing methods that require changing different testing equipment or devices for different test items, and to provide a solenoid valve electrical performance testing system.

[0005] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows:

[0006] A solenoid valve electrical performance testing system includes a connected main control unit and a testing unit, as well as a power supply unit for supplying power to the main control unit and the testing unit.

[0007] The main control unit of the device includes a main control computer, and a display and a communication bus module connected to it; the communication bus module includes an RS232 interface module and a network communication interface module.

[0008] The test unit includes a coil resistance test unit, an electrical parameter test unit, and multiple voltage and current detection units connected to the network communication interface module, as well as a test line switching module connected to the RS232 interface module and the equipment main control unit.

[0009] Both the coil resistance testing unit and the electrical parameter testing unit are connected to the test circuit switching module;

[0010] The voltage and current detection unit and the test circuit switching module are both connected to multiple solenoid valves.

[0011] The main control computer controls the coil resistance test unit, electrical parameter test unit, and multiple voltage and current detection units to test multiple solenoid valves, and displays the test information on the display.

[0012] Furthermore, the coil resistance testing unit includes a resistance testing instrument connected to the network communication interface module;

[0013] The electrical parameter testing unit includes a safety testing instrument connected to a network communication interface module;

[0014] The test line switching module includes a control module connected to the main control computer via an RS232 interface module, as well as a test switching relay matrix and a product switching relay matrix connected to the control module.

[0015] The test switching relay matrix is ​​connected to the product switching relay matrix;

[0016] The relay matrix for test switching is connected to the resistance test instrument and the safety test instrument; the relay matrix for product switching is connected to the solenoid valve.

[0017] Furthermore, the voltage and current detection unit includes a voltage acquisition module and a current acquisition module connected to the network communication interface module;

[0018] The voltage acquisition module includes an ADC voltage sampling module connected to a network communication interface module. The ADC voltage sampling module is connected to the power supply terminal of the solenoid valve through a pull-in voltage detection circuit and a power supply voltage detection circuit.

[0019] The current acquisition module includes an ADC current sampling module connected to the network communication interface module. The ADC current sampling module is connected to the power supply terminal of the solenoid valve through a power supply current detection circuit and a release current detection circuit.

[0020] Furthermore, the power supply voltage detection circuit includes an operational amplifier U1, the output terminal of which is connected to the negative input terminal of the operational amplifier U1 and one end of a resistor R11, the other end of which is connected to the ADC voltage sampling module and grounded through a capacitor C11;

[0021] The positive input terminal of operational amplifier U1 is connected to one end of resistor Ry11 and capacitor Cy11. The other end of capacitor Cy11 is grounded. The other end of resistor Ry11 is connected to the power supply terminal of solenoid valve through resistor Rs1 and grounded through resistor Rs2.

[0022] The positive power supply terminal of operational amplifier U1 is connected to the device power supply unit; the negative power supply terminal of operational amplifier U1 is grounded.

[0023] Furthermore, the pull-in voltage detection circuit includes an operational amplifier U7B, the output terminal of which is connected to the negative input terminal and one end of a resistor R39, the other end of which is connected to an ADC voltage sampling module and grounded through a capacitor C42;

[0024] The positive input terminal of operational amplifier U7B is grounded through capacitor C41 and resistor R42;

[0025] The positive input terminal of operational amplifier U7B is connected to one end of resistor R36, and the other end of resistor R36 is connected to the power supply terminal of the solenoid valve through resistor R33.

[0026] Furthermore, the power supply current detection circuit includes an operational amplifier U2, the output terminal of which is connected to one end of resistors Ry24 and R21; the other end of resistor Ry24 is connected to the negative input terminal of operational amplifier U2; the other end of resistor R21 is connected to the ADC current sampling module and grounded through capacitor C21.

[0027] The positive and negative input terminals of operational amplifier U2 are connected in series with resistors Ry21, Rs3, and Ry23, and the connection terminals of resistors Rs3 and Ry23 are connected to the power supply terminals of the solenoid valve.

[0028] The positive input terminal of operational amplifier U2 is grounded through resistor Ry22;

[0029] The positive power supply terminal of operational amplifier U2 is connected to the device power supply unit; the negative power supply terminal of operational amplifier U2 is grounded.

[0030] Furthermore, the release current detection circuit includes a current acquisition chip U11;

[0031] The first pin of the current acquisition chip U11 is connected to one end of resistor R51, and the other end of resistor R51 is connected to the ADC current sampling module and grounded through capacitor C46.

[0032] The second pin of the current acquisition chip U11 is grounded;

[0033] The third pin of the current acquisition chip U11 is connected to one end of capacitors C45 and C47 and resistor R50. The other end of capacitor C45 is grounded, the other end of capacitor C47 is connected to the fourth pin of the current acquisition chip U11, and the other end of resistor R50 is connected to the power supply terminal of the solenoid valve and one end of resistor R55.

[0034] The other end of resistor R55 is connected to one end of resistor R56 and the coil of the solenoid valve; the other end of resistor R56 is connected to the fourth pin of current acquisition chip U11 and one end of capacitor C48, and the other end of capacitor C48 is grounded.

[0035] The fifth pin of the current acquisition chip U11 is connected to one end of inductor FB4 and one end of capacitors C49 and C50. The other end of inductor FB4 is connected to the device power supply unit and one end of capacitor C61. The other ends of capacitors C49, C50 and C61 are grounded.

[0036] Furthermore, the device power supply unit includes a power plug, a common-mode filter, and a power supply module connected in sequence;

[0037] The common-mode filter is connected to the safety tester and the resistance tester;

[0038] The power supply module includes a switching power supply and a linear regulated power supply connected to a common-mode filter;

[0039] The switching power supply is connected to the voltage acquisition module, current acquisition module, and test circuit switching module through the first DC filter;

[0040] The linear regulated power supply is connected to multiple solenoid valves through a second DC filter.

[0041] Furthermore, the first DC filter includes a first-stage LC filter circuit, a second-stage filter circuit, and a common-mode inductor connecting the two.

[0042] The first-stage LC filter circuit includes a first magnetic ring inductor, one end of which is connected to the output terminal of the switching power supply, and the other end is connected to one end of a first filter capacitor and a second filter capacitor. The other ends of the first filter capacitor and the second filter capacitor are grounded.

[0043] The secondary LC filter circuit includes a second magnetic ring inductor. One end of the second magnetic ring inductor is connected to the voltage acquisition module, the current acquisition module, and the test line switching module, and is grounded through the third filter capacitor, the fourth filter capacitor, and the fifth filter capacitor.

[0044] The two ends of the first winding of the common-mode inductor are connected to the first magnetic ring inductor and the second magnetic ring inductor, respectively, and the two ends of the second winding of the common-mode inductor are grounded.

[0045] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0046] 1. The electromagnetic valve electrical performance testing system provided by this invention, by setting up a test circuit switching module, a coil resistance testing unit, an electrical parameter testing unit, and multiple voltage and current detection units, and then connecting multiple electromagnetic valves to multiple voltage and current detection units and the test circuit switching module, can realize the detection of electromagnetic valve coil resistance, insulation resistance, pull-in voltage, and release current in a single connection; moreover, the corresponding test results can be uploaded to the main control computer and directly displayed on the monitor; compared with existing testing equipment, there is no need to change different testing equipment according to different test items, which helps to improve testing efficiency and reduce the labor intensity of workers.

[0047] 2. The electromagnetic valve electrical performance testing system provided by the present invention, by setting up a test circuit switching module, the test switching relay matrix and product switching relay matrix in the test circuit switching module cooperate with the resistance test instrument and the safety test instrument, and then with the help of the main control module to control the test switching relay matrix and product switching relay matrix to switch the corresponding test channels, can realize the testing of the insulation resistance and coil resistance of electromagnetic valves in different channels. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention;

[0049] Figure 2 This is a schematic diagram of the structure of the relay matrix for test switching applied to the resistance test instrument in an embodiment of the present invention;

[0050] Figure 3 This is a schematic diagram of the structure of a relay matrix for product switching applied to a resistance testing instrument in an embodiment of the present invention;

[0051] Figure 4 This is a schematic diagram of the power supply voltage detection circuit in an embodiment of the present invention;

[0052] Figure 5 This is a schematic diagram of the power supply current detection circuit in an embodiment of the present invention;

[0053] Figure 6 This is a schematic diagram of the pull-in voltage detection circuit in an embodiment of the present invention;

[0054] Figure 7 This is a schematic diagram of the release current detection circuit in an embodiment of the present invention;

[0055] Figure 8 This is a schematic diagram of the power supply unit of the device in an embodiment of the present invention;

[0056] Figure 9 This is a schematic diagram of the power supply module in an embodiment of the present invention;

[0057] Figure 10 This is a schematic diagram of the structure of the first DC filter in an embodiment of the present invention. Detailed Implementation

[0058] The technical solutions of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0059] like Figure 1As shown, a solenoid valve electrical performance testing system includes a connected main control unit and a testing unit, as well as a power supply unit for supplying power to the main control unit and the testing unit. The main control unit includes a main control computer, and a display and a communication bus module connected to it. The communication bus module includes an RS232 interface module and a network communication interface module. The testing unit includes a coil resistance testing unit, an electrical parameter testing unit, and multiple voltage and current detection units connected to the network communication interface module, as well as a test circuit switching module connected to the RS232 interface module and the main control unit. The coil resistance testing unit and the electrical parameter testing unit are both connected to the test circuit switching module. The voltage and current detection units and the test circuit switching module are both connected to multiple solenoid valves. The main control computer controls the coil resistance testing unit, the electrical parameter testing unit, and the multiple voltage and current detection units to test the multiple solenoid valves respectively, and displays the test information on the display.

[0060] like Figure 1 As shown, the coil resistance testing unit includes a resistance testing instrument connected to the network communication interface module; the electrical parameter testing unit includes a safety testing instrument connected to the network communication interface module; as shown... Figure 2 and Figure 3 As shown, the test line switching module includes a control module connected to the main control computer via an RS232 interface module, and a test switching relay matrix and a product switching relay matrix connected to the control module; the test switching relay matrix and the product switching relay matrix are connected.

[0061] The relay matrix for test switching is connected to the resistance test instrument and the safety test instrument; the relay matrix for product switching is connected to the solenoid valve.

[0062] In this embodiment, a resistance tester and a safety tester are used to test five solenoid valves. The resistance tester is used to measure the resistance of the solenoid valve coils. Since the test cable is 4m long, a four-wire measurement method is used to measure the resistance of the solenoid valve coils, taking into account line losses. The safety tester is used to check the insulation resistance between the pins and the unpainted surface of the coil, and between the pins and the housing; or the dielectric strength between the pins and the unpainted surface of the coil, and between the pins and the housing.

[0063] In this embodiment, a high-precision six-and-a-half-digit digital resistance meter is selected as the resistance testing instrument. The resistance meter has a network communication interface, which facilitates the main control computer to read the measurement results in real time.

[0064] The test switching relay matrix is ​​used in combination with the product switching relay matrix. During testing, the test pins of the product under test are switched first through the product switching relay matrix, and then the test switching relay matrix is ​​used to complete the test.

[0065] The solenoid valve coil resistance test needs to be able to test 5 products, so a relay matrix is ​​required to switch the circuit.

[0066] To detect the resistance between pin 1 and pin 2, pin 3 and pin 4, pin 1 and pin 3, or pin 2 and pin 4; or to detect the resistance between pin 1 and pin 3, pin 1 and pin 4, pin 2 and pin 3, or pin 2 and pin 4 from the socket respectively.

[0067] When used to test the resistance of a solenoid valve coil, the relays in the product switching relay matrix are signal-level double-pole double-throw relays; when used to test the insulation resistance of a solenoid valve, the relays in the product switching relay matrix are high-voltage single-pole double-throw relays.

[0068] The control module, based on instructions from the main control computer, controls the test switching relay matrix and the product switching relay matrix to perform corresponding coil resistance or insulation resistance tests. The control module uses a 32-bit ARM series microcontroller as its core component. The control module receives control commands from the main control computer and controls the test switching relay matrix and the product switching relay matrix to perform the relevant actions.

[0069] like Figure 1 As shown, the voltage and current detection unit includes a voltage acquisition module and a current acquisition module connected to the network communication interface module; as Figure 4 As shown, the voltage acquisition module includes an ADC voltage sampling module connected to the network communication interface module. The ADC voltage sampling module is connected to the power supply terminal of the solenoid valve through a pull-in voltage detection circuit and a power supply voltage detection circuit; as shown... Figure 5 As shown, the current acquisition module includes an ADC current sampling module connected to the network communication interface module. The ADC current sampling module is connected to the power supply terminal of the solenoid valve through a power supply current detection circuit and a release current detection circuit.

[0070] like Figure 4 As shown, the power supply voltage detection circuit includes an operational amplifier U1. The output terminal of operational amplifier U1 is connected to the negative input terminal of operational amplifier U1 and one end of resistor R11. The other end of resistor R11 is connected to the ADC voltage sampling module and grounded through capacitor C11. The positive input terminal of operational amplifier U1 is connected to one end of resistor Ry11 and capacitor Cy11. The other end of capacitor Cy11 is grounded. The other end of resistor Ry11 is connected to the power supply terminal of the solenoid valve through resistor Rs1 and grounded through resistor Rs2. The positive power supply terminal of operational amplifier U1 is connected to the device power supply unit. The negative power supply terminal of operational amplifier U1 is grounded.

[0071] like Figure 6As shown, the pull-in voltage detection circuit includes an operational amplifier U7B. The output terminal of the operational amplifier U7B is connected to the negative input terminal and one end of the resistor R39. The other end of the resistor R39 is connected to the ADC voltage sampling module and grounded through the capacitor C42. The positive input terminal of the operational amplifier U7B is grounded through the capacitor C41 and the resistor R42. The positive input terminal of the operational amplifier U7B is connected to one end of the resistor R36. The other end of the resistor R36 is connected to the power supply terminal of the solenoid valve through the resistor R33.

[0072] like Figure 5 As shown, the power supply current detection circuit includes operational amplifier U2. The output terminal of operational amplifier U2 is connected to one end of resistors Ry24 and R21; the other end of resistor Ry24 is connected to the negative input terminal of operational amplifier U2; the other end of resistor R21 is connected to the ADC current sampling module and grounded through capacitor C21; resistors Ry21, Rs3, and Ry23 are connected in series between the positive and negative input terminals of operational amplifier U2, and the connection terminal of resistors Rs3 and Ry23 is connected to the power supply terminal of the solenoid valve; the positive input terminal of operational amplifier U2 is grounded through resistor Ry22; the positive power supply terminal of operational amplifier U2 is connected to the device power supply unit; and the negative power supply terminal of operational amplifier U2 is grounded.

[0073] like Figure 7 As shown, the release current detection circuit includes a current acquisition chip U11; the first pin of the current acquisition chip U11 is connected to one end of resistor R51, the other end of resistor R51 is connected to the ADC current sampling module, and grounded through capacitor C46; the second pin of the current acquisition chip U11 is grounded; the third pin of the current acquisition chip U11 is connected to capacitors C45 and C47 and one end of resistor R50, the other end of capacitor C45 is grounded, the other end of capacitor C47 is connected to the fourth pin of the current acquisition chip U11, the other end of resistor R50 is connected to the power supply terminal of the solenoid valve and one end of resistor R55; the other end of resistor R55 is connected to one end of resistor R56 and the coil of the solenoid valve; the other end of resistor R56 is connected to the fourth pin of the current acquisition chip U11 and one end of capacitor C48, the other end of capacitor C48 is grounded; the fifth pin of the current acquisition chip U11 is connected to one end of inductor FB4 and one end of capacitors C49 and C50, the other end of inductor FB4 is connected to the device power supply unit and one end of capacitor C61; the other ends of capacitors C49, C50 and C61 are grounded.

[0074] like Figure 8 As shown, the equipment power supply unit includes a power plug, a common-mode filter, and a power supply module connected in sequence; the common-mode filter is connected to the safety tester and the resistance tester.

[0075] like Figure 9As shown, the power supply module includes a switching power supply and a linear regulated power supply connected to a common-mode filter; the switching power supply is connected to a voltage acquisition module, a current acquisition module, and a test circuit switching module through a first DC filter; the linear regulated power supply is connected to multiple solenoid valves through a second DC filter.

[0076] like Figure 10 As shown, considering the stability of the DC power components inside the equipment and the anti-interference stability of the power supply of the product under test, the first DC filter includes a first-stage LC filter circuit, a second-stage filter circuit, and a common-mode inductor connecting the two.

[0077] The first-stage LC filter circuit includes a first magnetic ring inductor. One end of the first magnetic ring inductor is connected to the output terminal of the switching power supply, and the other end is connected to one end of the first filter capacitor and the second filter capacitor. The other ends of the first filter capacitor and the second filter capacitor are grounded.

[0078] The two-stage LC filter circuit includes a second magnetic ring inductor. One end of the second magnetic ring inductor is connected to the voltage acquisition module, the current acquisition module, and the test line switching module, and is grounded through the third, fourth, and fifth filter capacitors.

[0079] The two ends of the first winding of the common-mode inductor are connected to the first magnetic ring inductor and the second magnetic ring inductor, respectively, and the two ends of the second winding of the common-mode inductor are grounded.

[0080] The first DC filter is a DC power supply harmonic compensation device composed of inductors and capacitors. It can filter out harmonics in the power supply once or multiple times, thus purifying the DC power supply. At the same time, the first DC filter is equipped with a common-mode inductor for common-mode filtering, which solves the problem of fast transient group pulse interference with a repetition frequency of several kilohertz in the field.

[0081] In this embodiment, the solenoid valve electrical performance testing system is mainly used to detect the coil resistance, insulation resistance, pull-in voltage, and release current of the solenoid valve. The solenoid valve electrical performance testing system of this invention uses a resistance tester to detect the coil resistance, a safety tester to detect the insulation resistance, an ADC voltage sampling module in conjunction with a pull-in voltage detection circuit to detect the pull-in voltage, and an ADC current sampling module in conjunction with a release current detection circuit to detect the release current.

[0082] The electromagnetic valve electrical performance testing system of the present invention can detect the total voltage and total current of the product power supply, monitor the coil resistance and insulation resistance of the electromagnetic valve, and detect the pull-in voltage and release current under load or no-load conditions.

[0083] In other embodiments of the present invention, the pressure curve of the solenoid valve in practical application can be detected; the solenoid valve is used in a gas cylinder to conduct a filling and discharging experiment; the pressure of the gas cylinder during the filling and discharging process is monitored by a pressure sensor and the pressure curve is plotted by the main control computer, so as to realize the detection of the pressure curve of the solenoid valve in practical application.

[0084] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present invention should be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A solenoid valve electrical performance testing system, characterized in that: It includes a connected main control unit and a test unit, as well as a power supply unit for supplying power to the main control unit and the test unit; The main control unit of the device includes a main control computer, and a display and a communication bus module connected thereto; The communication bus module includes an RS232 interface module and a network communication interface module; The test unit includes a coil resistance test unit, an electrical parameter test unit, and multiple voltage and current detection units connected to the network communication interface module, as well as a test line switching module connected to the RS232 interface module and the equipment main control unit. Both the coil resistance testing unit and the electrical parameter testing unit are connected to the test circuit switching module; The voltage and current detection unit and the test circuit switching module are both connected to multiple solenoid valves. The main control computer controls the coil resistance test unit, electrical parameter test unit, and multiple voltage and current detection units to test multiple solenoid valves, and displays the test information on the display.

2. The electromagnetic valve electrical performance testing system according to claim 1, characterized in that: The coil resistance testing unit includes a resistance testing instrument connected to a network communication interface module; The electrical parameter testing unit includes a safety testing instrument connected to a network communication interface module; The test line switching module includes a control module connected to the main control computer via an RS232 interface module, as well as a test switching relay matrix and a product switching relay matrix connected to the control module. The test switching relay matrix is ​​connected to the product switching relay matrix; The relay matrix for test switching is connected to the resistance test instrument and the safety test instrument; the relay matrix for product switching is connected to the solenoid valve.

3. The electromagnetic valve electrical performance testing system according to claim 1, characterized in that: The voltage and current detection unit includes a voltage acquisition module and a current acquisition module connected to the network communication interface module; The voltage acquisition module includes an ADC voltage sampling module connected to a network communication interface module. The ADC voltage sampling module is connected to the power supply terminal of the solenoid valve through a pull-in voltage detection circuit and a power supply voltage detection circuit. The current acquisition module includes an ADC current sampling module connected to the network communication interface module. The ADC current sampling module is connected to the power supply terminal of the solenoid valve through a power supply current detection circuit and a release current detection circuit.

4. The electromagnetic valve electrical performance testing system according to claim 3, characterized in that: The power supply voltage detection circuit includes an operational amplifier U1. The output terminal of the operational amplifier U1 is connected to the negative input terminal of the operational amplifier U1 and one end of the resistor R11. The other end of the resistor R11 is connected to the ADC voltage sampling module and grounded through the capacitor C11. The positive input terminal of operational amplifier U1 is connected to one end of resistor Ry11 and capacitor Cy11. The other end of capacitor Cy11 is grounded. The other end of resistor Ry11 is connected to the power supply terminal of solenoid valve through resistor Rs1 and grounded through resistor Rs2. The positive power supply terminal of operational amplifier U1 is connected to the device power supply unit; the negative power supply terminal of operational amplifier U1 is grounded.

5. The electromagnetic valve electrical performance testing system according to claim 3, characterized in that: The pull-in voltage detection circuit includes an operational amplifier U7B. The output terminal of the operational amplifier U7B is connected to the negative input terminal and one end of the resistor R39. The other end of the resistor R39 is connected to the ADC voltage sampling module and grounded through the capacitor C42. The positive input terminal of operational amplifier U7B is grounded through capacitor C41 and resistor R42; The positive input terminal of operational amplifier U7B is connected to one end of resistor R36, and the other end of resistor R36 is connected to the power supply terminal of the solenoid valve through resistor R33.

6. The electromagnetic valve electrical performance testing system according to claim 3, characterized in that: The power supply current detection circuit includes an operational amplifier U2. The output terminal of the operational amplifier U2 is connected to one end of resistor Ry24 and resistor R21. The other end of resistor Ry24 is connected to the negative input terminal of the operational amplifier U2. The other end of resistor R21 is connected to the ADC current sampling module and grounded through capacitor C21. The positive and negative input terminals of operational amplifier U2 are connected in series with resistors Ry21, Rs3, and Ry23, and the connection terminals of resistors Rs3 and Ry23 are connected to the power supply terminals of the solenoid valve. The positive input terminal of operational amplifier U2 is grounded through resistor Ry22; The positive power supply terminal of operational amplifier U2 is connected to the device power supply unit; the negative power supply terminal of operational amplifier U2 is grounded.

7. The electromagnetic valve electrical performance testing system according to claim 3, characterized in that: The release current detection circuit includes a current acquisition chip U11; The first pin of the current acquisition chip U11 is connected to one end of resistor R51, and the other end of resistor R51 is connected to the ADC current sampling module and grounded through capacitor C46. The second pin of the current acquisition chip U11 is grounded; The third pin of the current acquisition chip U11 is connected to one end of capacitors C45 and C47 and resistor R50. The other end of capacitor C45 is grounded, the other end of capacitor C47 is connected to the fourth pin of the current acquisition chip U11, and the other end of resistor R50 is connected to the power supply terminal of the solenoid valve and one end of resistor R55. The other end of resistor R55 is connected to one end of resistor R56 and the coil of the solenoid valve; the other end of resistor R56 is connected to the fourth pin of current acquisition chip U11 and one end of capacitor C48, and the other end of capacitor C48 is grounded. The fifth pin of the current acquisition chip U11 is connected to one end of inductor FB4 and one end of capacitors C49 and C50. The other end of inductor FB4 is connected to the device power supply unit and one end of capacitor C61. The other ends of capacitors C49, C50 and C61 are grounded.

8. The electromagnetic valve electrical performance testing system according to claim 1, characterized in that: The device power supply unit includes a power plug, a common-mode filter, and a power supply module connected in sequence. The common-mode filter is connected to the safety tester and the resistance tester; The power supply module includes a switching power supply and a linear regulated power supply connected to a common-mode filter; The switching power supply is connected to the voltage acquisition module, current acquisition module, and test circuit switching module through the first DC filter; The linear regulated power supply is connected to multiple solenoid valves through a second DC filter.

9. The electromagnetic valve electrical performance testing system according to claim 8, characterized in that: The first DC filter includes a first-stage LC filter circuit, a second-stage filter circuit, and a common-mode inductor connecting the two. The first-stage LC filter circuit includes a first magnetic ring inductor, one end of which is connected to the output terminal of the switching power supply, and the other end is connected to one end of a first filter capacitor and a second filter capacitor. The other ends of the first filter capacitor and the second filter capacitor are grounded. The secondary LC filter circuit includes a second magnetic ring inductor. One end of the second magnetic ring inductor is connected to the voltage acquisition module, the current acquisition module, and the test line switching module, and is grounded through the third filter capacitor, the fourth filter capacitor, and the fifth filter capacitor. The two ends of the first winding of the common-mode inductor are connected to the first magnetic ring inductor and the second magnetic ring inductor, respectively, and the two ends of the second winding of the common-mode inductor are grounded.

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