Capacitor withstand voltage tester

Abstract

The utility model provides a capacitor withstand voltage tester which comprises a control system, a power supply, a high-voltage programmable power supply and a display module, the power supply, the high-voltage programmable power supply and the display module are connected to the control system, a main control module, a capacitor withstand voltage test module, a power conversion module and a communication module are arranged in the control system, and the capacitor withstand voltage test module, the power conversion module and the communication module are connected with the main control module; the capacitor withstand voltage test module is connected with the capacitor test clamp, the capacitor test clamp is connected with the high-voltage programmable power supply, the capacitor test clamp is used for placing a to-be-tested capacitor, the capacitor withstand voltage test module is used for carrying out withstand voltage test on the to-be-tested capacitor, and the high-voltage programmable power supply is used for providing a high-voltage voltage source and carrying out power supply voltage configuration through the communication module; the power supply conversion module is connected with a power supply and converts external power supply voltage into working voltage of each module, and the display module provides interface display. According to the invention, multiple channels of capacitors can be tested at the same time, the channels do not influence each other, the convenience of capacitor detection in the design and production process of automobile electronic control products is high, and the cost is low.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of capacitor testing, and particularly relates to a capacitor withstand voltage tester. BACKGROUND

[0002] In an electronic control system or component, the quality of the capacitor directly determines the reliability and service life of the product system, especially for automotive electrical control products.

[0003] The existing capacitor withstand voltage tester has few optional models that meet the requirements, and has the disadvantage that it cannot be connected in parallel with multiple modules. If multiple capacitors need to be tested simultaneously, multiple devices are required, which results in a large size that occupies the test site, and the need for a test personnel to look after it, which cannot achieve automatic and intelligent testing. Even worse, the safety is insufficient, and an explosion may occur during capacitor breakdown during the capacitor testing process, which may cause a fire, and if it splashes onto nearby flammable materials or the test personnel is close to the operation, it may cause incalculable losses and harm. CONTENT OF THE INVENTION

[0004] Therefore, the application aims to provide a capacitor withstand voltage tester to solve at least one of the above problems.

[0005] To achieve the above-mentioned purposes, the technical solution of the application is as follows:

[0006] The application provides a capacitor withstand voltage tester, comprising:

[0007] a control system, and a power supply, a high-voltage program-controlled power supply and a display module connected to the control system, wherein the control system is configured with a main control module, and a capacitor withstand voltage testing module, a power conversion module and a communication module connected to the main control module;

[0008] The capacitor withstand voltage testing module is connected to a capacitor testing clamp, the capacitor testing clamp is connected to the high-voltage program-controlled power supply, the capacitor testing clamp is used to place a capacitor to be tested, the capacitor withstand voltage testing module is used to test the withstand voltage of the capacitor to be tested, and the high-voltage program-controlled power supply is used to provide a high-voltage power supply and configure the power voltage through the communication module;

[0009] The power conversion module is connected to the power supply to convert an external power voltage into working voltages of each module, and the display module provides interface display.

[0010] Further, the capacitor testing clamp is a flip type box body structure, which is internally provided with multiple placement positions for placing the capacitors to be tested, and each placement position is fixed in position by a metal sheet.

[0011] The metal sheet is connected with the high-voltage programmed power supply and the capacitor voltage withstanding test module respectively.

[0012] Further, the capacitor voltage withstanding test module comprises a voltage withstanding test circuit with multiple channels, and each channel of the voltage withstanding test circuit is arranged corresponding to the metal sheet of each placement position.

[0013] The voltage withstanding test circuit comprises a current limiting circuit, a current collecting circuit and a test switch circuit connected in sequence.

[0014] Further, the current limiting circuit comprises a first switch tube, a first comparator and a second comparator.

[0015] The first comparator, the RC filter circuit, the fourth resistor and the twelfth resistor constitute a comparator circuit, the second comparator, the sixteenth resistor, the twenty-second resistor and the twenty-fourth resistor constitute a non-inverting amplifier circuit, the output end of the first comparator is connected with the first end of the first switch tube through the ninth resistor, the third end of the first switch tube is connected with the sixteenth resistor, the second end of the first switch tube is connected with one of the metal sheets, and the output end of the second comparator is connected with the inverting input end of the first comparator.

[0016] The other end of the RC filter circuit is connected with the main control module.

[0017] Further, the current collecting circuit comprises a follower circuit composed of a third comparator, a twenty-seventh resistor and an eighth capacitor, the other end of the twenty-seventh resistor is connected with the main control module, and the non-inverting input end of the third comparator is connected with the inverting input end of the first comparator and the output end of the second comparator respectively.

[0018] Further, the test switch circuit is composed of a first relay, a first diode and a third switch tube, the fourth end of the first relay is connected with the third end of the first switch tube through the nineteenth resistor, the seventh end of the first relay is grounded through the third thirty-third resistor and the third light emitting diode connected in sequence, the first end of the first relay is connected with the second end of the first relay through the first diode, the cathode of the first diode is connected with the BATT_12V power supply end, the anode of the first diode is connected with the third end of the third switch tube, and the first end of the third switch tube is connected with the main control module through the third thirty-fifth resistor.

[0019] Further, a high-voltage collecting circuit is further included, the high-voltage collecting circuit is connected with the main control module, and is composed of multiple series resistors.

[0020] Further, the communication module comprises an RS485 communication circuit, which is connected with the main control module and the high-voltage programmed power supply through a communication serial port.

[0021] Further, the main control module is further connected with a function button for setting the capacitor voltage resistance test.

[0022] Further, the display module adopts an LED display screen, which is connected with the main control module through a connection port to provide a man-machine interactive interface for display.

[0023] Compared with the prior art, the capacitor voltage resistance tester has the following beneficial effects:

[0024] Compared with the traditional capacitor tester, the capacitor voltage resistance tester has the characteristics of small size, flexible setting of applied voltage and breakdown current, convenient and safe use, and no explosion and burning of test contacts, and can test multiple capacitors simultaneously without mutual influence between channels and damage to other channel circuits, which is convenient for capacitor detection in the design and production process of automobile electric control products and has low cost. BRIEF DESCRIPTION OF DRAWINGS

[0025] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application and are incorporated herein in their entirety. The embodiments illustrated in the drawings are provided to explain the present application and are not intended to limit the present application. In the drawings:

[0026] Figure 1 A capacitor voltage resistance tester system block diagram according to an embodiment of the present application;

[0027] Figure 2 A high-voltage programmed power supply, a high-voltage acquisition circuit and a capacitor test circuit diagram according to an embodiment of the present application;

[0028] Figure 3 A main control module circuit diagram according to an embodiment of the present application;

[0029] Figure 4 A capacitor voltage resistance test circuit diagram according to an embodiment of the present application;

[0030] Figure 5 A power conversion module circuit diagram according to an embodiment of the present application;

[0031] Figure 6 An RS485 communication circuit diagram according to an embodiment of the present application;

[0032] Figure 7 A linear voltage regulator circuit diagram according to an embodiment of the present application;

[0033] Figure 8 The functional button circuit diagram for the embodiments of the present application is shown in the following figure:

[0034] Figure 9 The LED display screen connection port circuit diagram for the embodiments of the present application is shown in the following figure. DETAILED DESCRIPTION

[0035] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the embodiments and the accompanying drawings.

[0036] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be understood as the common meanings understood by those with ordinary skills in the art to which the present application belongs. The terms "first", "second", and similar terms used in the embodiments of the present application do not represent any order, number, or importance, but are only used to distinguish different components. The terms "comprise", "include", and similar terms mean that the elements or objects before the terms encompass the elements or objects listed after the terms and their equivalents, and do not exclude other elements or objects. The terms "connect" or "connected" and similar terms do not mean physical or mechanical connections, but can be logical or electrical connections, which include electrical connections, whether direct or indirect.

[0037] The terms "up", "down", "left", "right", and the like only represent relative positional relationships, which may change accordingly when the absolute positions of the described objects change.

[0038] Referring to Figure 1 The embodiments provide a capacitor voltage withstand tester, which comprises:

[0039] a control system, and a power supply, a high-voltage program-controlled power supply, and a display module connected to the control system, wherein the control system is configured with a main control module, and a capacitor voltage withstand test module, a power supply conversion module, and a communication module connected to the main control module;

[0040] The capacitor voltage withstand test module is connected to a capacitor test clamp, the capacitor test clamp is connected to the high-voltage program-controlled power supply, the capacitor test clamp is used to place a capacitor to be tested, the capacitor voltage withstand test module is used to test the voltage withstand of the capacitor to be tested, and the high-voltage program-controlled power supply is used to provide a high-voltage power supply and configure the power supply voltage through the communication module;

[0041] The power supply conversion module is connected to the power supply to convert an external power supply voltage into working voltages of each module, and the display module provides interface display.

[0042] Specifically, in the embodiment, the tester is composed of a control system (composed of a master control module, a capacitor voltage withstand test module, a power conversion module, a communication module), a power supply, a high-voltage programmed power supply, a display module and a capacitor test clamp, and each module unit cooperates with each other to support multiple modules and multiple capacitors (only four capacitors are shown in the figure Figure 2 In the embodiment, the number of capacitors to be tested is not specifically limited, and only one capacitor can be tested, or multiple capacitors can be tested at the same time. The detection parameters can be adjusted according to requirements, which can meet the daily capacitor incoming inspection and also be suitable for troubleshooting of abnormal damaged capacitors and reproducing failure conditions to locate problem points.

[0043] In the embodiment, the power supply part is divided into a high-voltage source and a system power supply, and specifically as follows:

[0044] The high-voltage source part: the high-voltage source uses a power supply capable of establishing RS485 communication with the tester as a high-voltage generator to supply the capacitor test circuit, and generally uses a nominal 0-300V and a current of 0-5A.

[0045] The system power supply part: J3 is an external input DC 12V to supply power to the relay (K1 / K2 / K3 / K4), the operational amplifier (U1 / U2 / U5 / U6) and the DC-DC power supply chip (U8), wherein U8 is used as a BUCK step-down chip to provide a 5V reference power supply for the ADC of the single-chip microcomputer and also as an input for the linear voltage stabilizer U10 (as shown in Figure 7

[0046] The capacitor voltage withstand test clamp described in the embodiment has the characteristics of small size, flexible setting of applied voltage and breakdown current, convenient and safe use, and no explosion and burning of test contacts, and can test multiple capacitors at the same time, and the channels will not affect each other and will not affect and damage other channel circuits. It is convenient for capacitor detection in the design and production process of automotive electronic control products, and has low cost.

[0047] In some embodiments, as shown in Figure 2 The capacitor test clamp is a flip cover box structure, which has multiple placement positions for placing multiple capacitors to be tested, and each placement position is fixed by a metal sheet;

[0048] The metal sheet is connected with the high-voltage programmed power supply and the capacitor voltage withstand test module.

[0049] ​Specifically, in the embodiment, the capacitor test clamp adopts a flip cover type box body structure design, a cavity body is arranged in the box body, a plurality of placement positions for placing the to-be-tested capacitors are reserved in the cavity body, and a group of metal sheets is arranged on each placement position, each group of metal sheets is arranged in an upper and lower manner by two metal sheet units, and a gap is reserved between the two metal sheets, and the to-be-tested capacitors are fixed and positioned by the two metal sheets.

[0050] It should be noted that the structure of the capacitor test clamp is not within the protection scope of the application, that is, the embodiment only provides a limiting position mode for fixing the to-be-tested capacitors, and other structures capable of realizing the limiting position mode are within the protection scope of the application, and will not be described in detail here.

[0051] In some embodiments, as shown in Figure 3 and Figure 4 The capacitor voltage withstand test module includes a voltage withstand test circuit with multiple channels, and the voltage withstand test circuit of each channel is arranged corresponding to the metal sheet of each placement position.

[0052] The voltage withstand test circuit includes a current limiting circuit, a current collection circuit and a test switch circuit.

[0053] The current limiting circuit includes a first switch tube Q1, a first comparator U1A and a second comparator U1B.

[0054] The first comparator U1A, an RC filter circuit (the RC filter circuit is composed of R1, C3, R2, C4, R3 and R14), a fourth resistor R4 and a twelfth resistor R12 constitute a comparator circuit, the second comparator U1B and a sixteenth resistor R16, a twenty-second resistor R22 and a twenty-fourth resistor R24 constitute a non-inverting amplifier circuit, the output end of the first comparator U1A is connected with the first end of the first switch tube Q1 through a ninth resistor R9, the third end of the first switch tube Q1 is connected with the sixteenth resistor R16, the second end of the first switch tube Q1 is connected with one of the metal sheets, and the output end of the second comparator U1B is connected with the inverting input end of the first comparator U1A.

[0055] The other end of the RC filter circuit is connected with a master control module.

[0056] The current collection circuit includes a follower circuit composed of a third comparator U3A, a twenty-seventh resistor R27 and an eighth capacitor C8, the other end of the twenty-seventh resistor R27 is connected with the master control module U4A, and the non-inverting input end of the third comparator U3A is connected with the inverting input end of the first comparator U1A and the output end of the second comparator U1B respectively.

[0057] Wherein, the test switch circuit is composed of the first relay K1, the first diode D1 and the third switch tube Q3, the fourth end of the first relay K1 is connected with the third end of the first switch tube Q1 through the nineteenth resistor R19, the seventh end of the first relay K1 is grounded through the third thirty-three resistor R33 and the third light emitting diode D3 connected in parallel, the first end of the first relay K1 is connected with the second end thereof, and the cathode of the first diode D1 is connected with the BATT_12V power supply end, the anode of the first diode D1 is connected with the third end of the third switch tube Q3, and the first end of the third switch tube Q3 is connected with the main control module U4A through the third thirty-five resistor R35.

[0058] Specifically, in the embodiment, the number of the withstand voltage test circuits is not specifically limited, and only the withstand voltage test circuit providing one channel is explained and described as follows:

[0059] The current limiting circuit: Q1 is used as a switch tube, R19 is used as a sampling resistor, U1B / R16 / R22 / R24 is used to form a non-inverting amplifier, and the amplification coefficient is A=VOUT / VIN=1+(R22 / R24)=1+(22000 / 680)=33.35; the current collected by the R19 resistor is amplified by 33 times. The 7th pin of U1B is output to the 2nd pin of U1A, which is the inverting input terminal, and the comparator circuit composed of U1A / R1 / C3 / R2 / C4 / R3 / R14 / R4 / R12, the output of U1B is compared with the 3rd pin of U1A, which is the non-inverting terminal, wherein R1 / C3 / R2 / C4 / R3 / R14 is an RC filter, and the 10KHz PWM wave given by the single-chip microcomputer is filtered into a stable DC voltage. When the voltage at the non-inverting terminal is greater than the voltage at the inverting terminal, the 1st pin of U1A outputs a high level to open the Q1 switch tube. When the voltage at the non-inverting terminal is less than the voltage at the inverting terminal, the 1st pin of U1A outputs a low level to close the Q1 switch tube.

[0060] When the capacitor applies a direct current voltage (passing alternating current), no current will pass through, so U1B always maintains 0V, and U1A maintains a high level output to drive the Q1 switch tube to ensure conduction to the ground. Only when the capacitor is short-circuited to the ground after breakdown, the current limiting circuit will work. Since the current limiting is done, there will be no explosion and burst problem, and the test clamp contact point will not be burned out due to overcurrent. The whole test process is relatively quiet and safe.

[0061] Current acquisition circuit: the current acquisition circuit is composed of U3A / R27 / C8 to form a follower circuit, and the voltage output by U1B is sent to the ADC port of the single-chip microcomputer. When the capacitor is broken down and has a weak current flowing through, there will be a voltage division on the R19 resistor, and the single-chip microcomputer will compare the current value with the set value. When the current value is greater than the set value, the puncture high voltage and the breakdown capacitor channel at this time will be recorded.

[0062] Test switch circuit: after breakdown occurs, ensure that the switch tube keeps the passage in a constant current state, at which time the heat generated by the switch tube is large, and the relay K1 is driven by Q3 through the GPIO port to record the completion of the breakdown high voltage and the breakdown capacitor channel, and the relay K1 is cut off to the ground. After switching, the switching indication is completed by the LED lamp.

[0063] In some embodiments, as shown in Figure 2 The high-voltage acquisition circuit is connected with the main control module and is composed of a plurality of series resistors.

[0064] Specifically, in the present embodiment, the series resistor method is used to make a high-voltage power supply acquisition circuit, and R11 / R18 / R21 / R26 / R29 / R30 / R32 form a high-voltage voltage division network. The division ratio is 1:60. When the high-voltage power supply outputs 300V, the single-chip microcomputer acquisition port voltage is VIN=(10K÷(100K+100K+100K+100K+100K+100K+10K))×300V=4.918V; power calculation: W=U2 / R=90000 / 610000=0.147W<0.5W (1210 package).

[0065] In some embodiments, as shown in Figure 6 The communication module includes an RS485 communication circuit, which is connected with the main control module and connected with the high-voltage programmable power supply through a communication serial port.

[0066] As shown in Figure 8 The main control module is also connected with function keys for setting the capacitor voltage withstand test.

[0067] As shown in Figure 9 The display module uses an LED display screen, and the display screen is connected with the main control module through a connection port to provide a man-machine interactive interface for display.

[0068] Specifically, in the present embodiment, as shown in Figure 5 The main control module is a single-chip microcomputer minimum system (U4), which mainly processes external key input (KEY1 start / stop, KEY2 setting, KEY3 increase +, KEY4 decrease -) to set the size of the initial experimental voltage and the size of the limiting current, LED display (as a man-machine interactive interface to set and record experimental parameters, and display power, communication, test state and results, etc.).

[0069] The RS485 circuit (U9) serves as a communication bridge with the external high-voltage source (J1) to realize the application of the voltage and the step voltage value of the capacitor experiment high-voltage source according to the setting.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application.

[0071] The present application embodiments are intended to cover all such alternatives, modifications and variations that fall within the broad scope of the appended claims. Accordingly, any omission, modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application embodiments should be included in the protection scope of the present application.

Claims

1. A capacitor withstand voltage tester characterized by comprising: The application relates to a capacitor voltage withstand testing instrument. The application comprises a control system, a power supply connected to the control system, a high-voltage program-controlled power supply and a display module, wherein a main control module is arranged in the control system, and a capacitor voltage withstand testing module, a power supply conversion module and a communication module are connected to the main control module. The capacitor voltage withstand testing module is connected with a capacitor testing clamp, the capacitor testing clamp is connected with the high-voltage program-controlled power supply, the capacitor testing clamp is used for placing a capacitor to be tested, the capacitor voltage withstand testing module is used for performing voltage withstand testing on the capacitor to be tested, the high-voltage program-controlled power supply is used for providing a high-voltage power supply, and the power supply voltage is configured through the communication module. The power supply conversion module is connected with the power supply, and external power supply voltage is converted into working voltage of each module, and the display module provides interface display.

2. The capacitor voltage withstand testing instrument according to claim 1, wherein the capacitor testing clamp is a flip cover box structure, a plurality of capacitor placing positions for placing the capacitor to be tested are arranged in the capacitor testing clamp, and each capacitor placing position is fixed through a metal sheet. The metal sheet is connected with the high-voltage program-controlled power supply and the capacitor voltage withstand testing module.

3. The capacitor voltage withstand testing instrument according to claim 2, wherein the capacitor voltage withstand testing module comprises a voltage withstand testing circuit with multiple channels, and the voltage withstand testing circuit of each channel is arranged in correspondence with the metal sheet of each capacitor placing position. The voltage withstand testing circuit comprises a current limiting circuit, a current acquisition circuit and a testing switch circuit.

4. The capacitor voltage withstand testing instrument according to claim 3, wherein the current limiting circuit comprises a first switch tube, a first comparator and a second comparator. The first comparator, an RC filter circuit, a fourth resistor and a twelfth resistor constitute a comparator circuit, the second comparator, a sixteenth resistor, a twenty-second resistor and a twenty-fourth resistor constitute a non-inverting amplifier circuit, the output end of the first comparator is connected with the first end of the first switch tube through a ninth resistor, the third end of the first switch tube is connected with the sixteenth resistor, the second end of the first switch tube is connected with one of the metal sheets, and the output end of the second comparator is connected with the inverting input end of the first comparator. The other end of the RC filter circuit is connected with the main control module.

5. The capacitor voltage withstand testing instrument according to claim 4, wherein the current acquisition circuit comprises a follower circuit composed of a third comparator, a twenty-seventh resistor and an eighth capacitor, the other end of the twenty-seventh resistor is connected with the main control module, and the non-inverting input end of the third comparator is connected with the inverting input end of the first comparator and the output end of the second comparator.

6. The capacitor voltage withstand testing instrument according to claim 4, wherein ​ ​ ​ ​ The test switch circuit is composed of a first relay, a first diode and a third switch tube, a fourth end of the first relay is connected with a third end of the first switch tube through a nineteenth resistance, a seventh end of the first relay is grounded through a third thirty-three resistance and a third light emitting diode connected in parallel, a first diode is connected between a first end and a second end of the first relay, a cathode of the first diode is connected with a BATT_12V power supply end, an anode of the first diode is connected with the third end of the third switch tube, and a first end of the third switch tube is connected with the main control module through a third thirty-five resistance.

7. The capacitor voltage withstanding tester according to claim 3, characterized in that: Further comprising a high voltage acquisition circuit, the high voltage acquisition circuit is connected with the main control module, and is composed of a plurality of series resistors.

8. The capacitor voltage withstanding tester according to claim 1, characterized in that: The communication module comprises an RS485 communication circuit, the RS485 communication circuit is connected with the main control module and connected with the high voltage programmable power supply through a communication serial port respectively.

9. The capacitor voltage withstanding tester according to claim 1, characterized in that: The main control module is further connected with a function button, which is used for setting the capacitor voltage withstanding test.

10. The capacitor voltage withstanding tester according to claim 1, characterized in that: The display module adopts an LED display screen, the display screen is connected with the main control module through a connection port to provide a man-machine interactive interface for display.

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