Portable electrolytic capacitor leakage current tester

Abstract

The utility model, which relates to the testing field, discloses a portable electrolytic capacitor leakage current tester comprising a storage battery used for providing a DC input voltage for a DC-AC-DC circuit; the DC-AC-DC circuit is used for converting the direct current into alternating current, boosting the alternating current, then converting the alternating current into direct current and outputting the direct current to serve as a test power supply of the electrolytic capacitor; the electrolytic capacitor test circuit is used for receiving control of the single chip microcomputer, completing electrolytic capacitor test and transmitting test data to the single chip microcomputer; the beneficial effects of the utility model are that an AC 220V power supply is cancelled, a lithium battery and other high-energy density storage batteries are used for supplying power inside, and a Bluetooth emission circuit is added, so that the device is especially suitable for occasions requiring mobile testing in an electrolytic capacitor manufacturing production line or capacitor fault failure analysis in a client application field; and the Bluetooth transmitting circuit can directly send and store the test result to a PC (Personal Computer), so that the complexity of manual recording is avoided.

Description

Technical Field

[0001] The utility model relates to the field of testing, in particular to a portable electrolytic capacitor leakage current tester. Background Art

[0002] Existing electrolytic capacitor leakage current testers are usually desktop devices, placed on a test bench or embedded in electrolytic capacitor manufacturing equipment, and are used to detect the leakage current performance of aluminum electrolytic capacitors or screen defective products.

[0003] This kind of desktop equipment is not flexible enough to use and requires an external 220V AC power supply, so the use site is usually fixed: ① It is not convenient for any on-site quality monitoring during the electrolytic capacitor manufacturing process; ② It is not convenient to carry it to the electrolytic capacitor application client for device failure analysis, which needs to be improved. Utility Model Content

[0004] The purpose of the utility model is to provide a portable electrolytic capacitor leakage current tester to solve the problems raised in the above background technology.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A portable electrolytic capacitor leakage current tester, comprising:

[0007] A battery for providing a DC input voltage to a DC-AC-DC circuit;

[0008] DC-AC-DC circuit, used to convert DC power into AC power and then convert it into DC power output as the test power supply for electrolytic capacitors;

[0009] The electrolytic capacitor test circuit is used to receive the control of the single chip microcomputer, complete the electrolytic capacitor test, and transmit the test data to the single chip microcomputer;

[0010] Single chip microcomputer for comprehensive processing of electrolytic capacitor testing;

[0011] The keyboard input circuit is used to set the parameters of the charging current Iset, the test voltage Vset, and the holding time t corresponding to the leakage current, and control the operation of the electrolytic capacitor test circuit through the single-chip microcomputer;

[0012] The Bluetooth transmitting circuit is used to send the leakage current data obtained by the microcontroller to the PC;

[0013] The display screen is used to receive the transmission data of the single chip microcomputer and display the parameters of the electrolytic capacitor voltage value VCT, the leakage current value ILC, and the charging holding time tdelay in real time;

[0014] The storage battery is connected to the DC-AC-DC circuit, the DC-AC-DC circuit is connected to the electrolytic capacitor test circuit, the electrolytic capacitor test circuit is connected to the single-chip computer, the single-chip computer is connected to the Bluetooth transmitting circuit and the display circuit, and the keyboard input circuit is connected to the single-chip computer circuit.

[0015] As a further solution of the utility model: the DC-AC-DC circuit includes a high-frequency push-pull inverter circuit, a high-frequency transformer boost circuit, and a rectifier voltage-stabilizing circuit. The input end of the high-frequency push-pull inverter circuit is connected to the battery, the output end of the high-frequency push-pull inverter circuit is connected to the input end of the high-frequency transformer boost circuit, and the output end of the high-frequency transformer boost circuit is connected to the input end of the rectifier voltage-stabilizing circuit.

[0016] As a further solution of the utility model: the electrolytic capacitor test circuit includes a transistor Q1, a transistor Q2, an electrolytic capacitor CT, a sampling resistor RIT, a resistor R1, a resistor R2, an amplifier COMP1, and an amplifier COMP2. The collector of the transistor Q1 is connected to the positive output terminal of the DC-AC-DC circuit, the emitter of the transistor Q1 is connected to one end of the electrolytic capacitor CT and one end of the resistor R1, the base of the transistor Q1 is connected to the output end of the amplifier COMP1 after level isolation, the in-phase end of the amplifier COMP1 is connected to the single-chip microcomputer through a D / A conversion-1 circuit (D / A converter or related conversion circuit can be used), and the electrolytic The other end of the capacitor CT is connected to one end of the sampling resistor RIT and the input end of the amplifier A1, the other end of the sampling resistor RIT is connected to one end of the resistor R2 and the collector of the transistor Q2, the emitter of the transistor Q2 is connected to the negative electrode of the battery, the other end of the resistor R2 is connected to the other end of the resistor R1, the base of the transistor Q2 is connected to the output end of the amplifier COMP2 after level isolation, the in-phase end of the amplifier COMP2 is connected to the single-chip microcomputer through the D / A conversion-2 circuit (D / A converter or related conversion circuit can be), and the output end of the amplifier A1 is connected to the single-chip microcomputer through the A / D conversion circuit (A / D converter or related conversion circuit can be).

[0017] As a further solution of the utility model: the electrolytic capacitor testing circuit also includes a resistor R3 and a capacitor C3, one end of the resistor R3 is connected to the output end of the amplifier COMP1, the other end of the resistor R3 is connected to one end of the capacitor C3, and the other end of the capacitor C3 is connected to the other end of the resistor R1 and the inverting end of the amplifier COMP1.

[0018] As a further solution of the utility model: the electrolytic capacitor testing circuit also includes a resistor R4 and a capacitor C4, one end of the resistor R4 is connected to the output end of the amplifier COMP2, the other end of the resistor R4 is connected to one end of the capacitor C4, and the other end of the capacitor C4 is connected to the output end of the amplifier A1 and the inverting end of the amplifier COMP2.

[0019] Compared with the prior art, the beneficial effects of the utility model are as follows: the utility model cancels the AC 220V power supply, uses a high-energy-density battery such as a lithium battery for internal power supply, and adds a Bluetooth transmitting circuit (a relevant Bluetooth communication module can be used), which is particularly suitable for occasions where mobile testing is required in electrolytic capacitor manufacturing production lines, or for capacitor failure analysis at customer application sites; the Bluetooth transmitting circuit can enable the test results to be directly sent and saved to a PC, eliminating the tedious manual recording. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The utility model is a circuit diagram of a portable electrolytic capacitor leakage current tester. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0022] See also Figure 1 , a portable electrolytic capacitor leakage current tester, comprising:

[0023] A battery for providing a DC input voltage to a DC-AC-DC circuit;

[0024] DC-AC-DC circuit, used to convert DC power into AC power and then convert it into DC power output as the test power supply for electrolytic capacitors;

[0025] The electrolytic capacitor test circuit is used to receive the control of the single chip microcomputer, complete the electrolytic capacitor test, and transmit the test data to the single chip microcomputer;

[0026] Single chip microcomputer for comprehensive processing of electrolytic capacitor testing;

[0027] The keyboard input circuit is used to set the parameters of the charging current Iset, the test voltage Vset, and the holding time t corresponding to the leakage current, and control the operation of the electrolytic capacitor test circuit through the single-chip microcomputer;

[0028] The Bluetooth transmitting circuit is used to send the leakage current data obtained by the single-chip microcomputer to the PC. The wireless serial port communication sends the measured leakage current data to the PC, which has a paired Bluetooth receiving module.

[0029] The display screen is used to receive the transmission data of the single chip microcomputer and display the parameters of the electrolytic capacitor voltage value VCT, the leakage current value ILC, and the charging holding time tdelay in real time;

[0030] The storage battery is connected to the DC-AC-DC circuit, the DC-AC-DC circuit is connected to the electrolytic capacitor test circuit, the electrolytic capacitor test circuit is connected to the single-chip computer, the single-chip computer is connected to the Bluetooth transmitting circuit and the display circuit, and the keyboard input circuit is connected to the single-chip computer circuit.

[0031] In this example: See Figure 1 The DC-AC-DC circuit includes a high-frequency push-pull inverter circuit, a high-frequency transformer boost circuit, and a rectifier voltage stabilizing circuit. The input end of the high-frequency push-pull inverter circuit is connected to the battery, the output end of the high-frequency push-pull inverter circuit is connected to the input end of the high-frequency transformer boost circuit, and the output end of the high-frequency transformer boost circuit is connected to the input end of the rectifier voltage stabilizing circuit.

[0032] High-frequency push-pull inverter circuit DC-AC, high-frequency transformer boost circuit AC-AC and rectifier voltage stabilizing circuit AC-DC, the entire DC-AC-DC circuit converts low-voltage direct current into stable high-voltage direct current.

[0033] In this example: See Figure 1 The electrolytic capacitor test circuit includes transistor Q1, transistor Q2, electrolytic capacitor CT, sampling resistor RIT, resistor R1, resistor R2, amplifier COMP1, amplifier COMP2, the collector of transistor Q1 is connected to the positive output terminal of the DC-AC-DC circuit, the emitter of transistor Q1 is connected to one end of the electrolytic capacitor CT and one end of the resistor R1, the base of transistor Q1 is connected to the output end of amplifier COMP1 after level isolation, the in-phase end of amplifier COMP1 is connected to the microcontroller through a D / A conversion-1 circuit (D / A converter or related conversion circuit can be used), and the other end of the electrolytic capacitor CT is connected to the microcontroller. The first end is connected to one end of the sampling resistor RIT and the input end of the amplifier A1, the other end of the sampling resistor RIT is connected to one end of the resistor R2 and the collector of the transistor Q2, the emitter of the transistor Q2 is connected to the negative electrode of the battery, the other end of the resistor R2 is connected to the other end of the resistor R1, the base of the transistor Q2 is connected to the output end of the amplifier COMP2 after level isolation, the in-phase end of the amplifier COMP2 is connected to the single-chip microcomputer through the D / A conversion-2 circuit (D / A converter or related conversion circuit can be), and the output end of the amplifier A1 is connected to the single-chip microcomputer through the A / D conversion circuit (A / D converter or related conversion circuit can be).

[0034] The electrolytic capacitor CT is the capacitor to be tested, and the transistor Q1 is used as a voltage regulator to ensure that the voltage meets the set value Vset and is maintained during the leakage current test after the electrolytic capacitor CT is charged. The transistor Q2 is used as a constant current regulator to ensure that the charging current of the electrolytic capacitor CT meets the set value Iset during the charging and voltage boosting. The sampling resistor RIT converts the current flowing through the electrolytic capacitor CT to be tested, including the charging current Ich in the charging stage and the leakage current ILC in the constant voltage test stage, into a voltage. In order to reduce the influence of the voltage on the sampling resistor RIT on the capacitor voltage, the resistance value of the sampling resistor RIT is very small.

[0035] Resistors R1 and R2 are voltage sampling resistors. Resistors R1 and R2 divide the voltage in proportion. By testing the voltage on resistor R2, the voltage VCT of the electrolytic capacitor can be obtained. Amplifier A1 is used to amplify the weak voltage signal on the sampling resistor RIT by K times. The A / D conversion circuit uses an analog / digital converter to convert the voltage analog signal amplified by amplifier A1 into a digital signal for processing by the single-chip microcomputer. The D / A conversion-1 circuit performs digital-to-analog conversion, and is used to convert the voltage setting digital value input by the keyboard into an analog voltage value, which is input to the in-phase input terminal of amplifier COMP1; the D / A conversion-2 circuit performs digital-to-analog conversion, and is used to convert the charging current setting digital value input by the keyboard into an analog voltage value, which is input to the in-phase input terminal of amplifier COMP2.

[0036] In this example: See Figure 1 The electrolytic capacitor test circuit also includes a resistor R3 and a capacitor C3, one end of the resistor R3 is connected to the output end of the amplifier COMP1, the other end of the resistor R3 is connected to one end of the capacitor C3, and the other end of the capacitor C3 is connected to the other end of the resistor R1 and the inverting end of the amplifier COMP1.

[0037] In this example: See Figure 1 The electrolytic capacitor test circuit also includes a resistor R4 and a capacitor C4, one end of the resistor R4 is connected to the output end of the amplifier COMP2, the other end of the resistor R4 is connected to one end of the capacitor C4, and the other end of the capacitor C4 is connected to the output end of the amplifier A1 and the inverting end of the amplifier COMP2.

[0038] The resistor R3, the capacitor C3, the resistor R4, the capacitor C4 respectively form feedback compensation of the voltage comparators COMP1 and COMP2.

[0039] The working principle of the utility model is: the battery is used to provide a DC input voltage for the DC-AC-DC circuit;

[0040] The DC-AC-DC circuit is used to convert direct current into alternating current and then convert it into direct current output after voltage boosting, which is used as the test power supply for the electrolytic capacitor; the electrolytic capacitor test circuit is used to receive the control of the single-chip microcomputer, complete the electrolytic capacitor test, and transmit the test data to the single-chip microcomputer; the single-chip microcomputer is used to comprehensively process the electrolytic capacitor test; the keyboard input circuit is used to set the parameters of the charging current Iset, the test voltage Vset, and the holding time t corresponding to the leakage current, and the operation of the electrolytic capacitor test circuit is controlled by the single-chip microcomputer; the Bluetooth transmitting circuit is used to send the leakage current data obtained by the single-chip microcomputer to the PC computer side; wireless serial port communication sends the measured leakage current data to the PC computer side, and the PC computer side has a paired Bluetooth receiving module; the display screen is used to receive the transmission data of the single-chip microcomputer, and display the parameters of the electrolytic capacitor voltage value VCT, the leakage current value ILC, and the charging holding time tdelay in real time.

[0041] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0042] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A portable electrolytic capacitor leakage current tester, It is characterized in that This portable electrolytic capacitor leakage current tester includes: A battery for providing a DC input voltage to a DC-AC-DC circuit; DC-AC-DC circuit, used to convert DC power into AC power and then convert it into DC power output as the test power supply for electrolytic capacitors; The electrolytic capacitor test circuit is used to receive the control of the single chip microcomputer, complete the electrolytic capacitor test, and transmit the test data to the single chip microcomputer; Single chip microcomputer for comprehensive processing of electrolytic capacitor testing; The keyboard input circuit is used to set the parameters of the charging current Iset, the test voltage Vset, and the holding time t corresponding to the leakage current, and control the operation of the electrolytic capacitor test circuit through the single-chip microcomputer; The Bluetooth transmitting circuit is used to send the leakage current data obtained by the microcontroller to the PC; The display screen is used to receive the transmission data of the single chip microcomputer and display the parameters of the electrolytic capacitor voltage value VCT, the leakage current value ILC, and the charging holding time tdelay in real time; The storage battery is connected to the DC-AC-DC circuit, the DC-AC-DC circuit is connected to the electrolytic capacitor test circuit, the electrolytic capacitor test circuit is connected to the single-chip computer, the single-chip computer is connected to the Bluetooth transmitting circuit and the display circuit, and the keyboard input circuit is connected to the single-chip computer circuit.

2. The portable electrolytic capacitor leakage current tester according to claim 1, It is characterized in that The DC-AC-DC circuit includes a high-frequency push-pull inverter circuit, a high-frequency transformer boost circuit, and a rectifier voltage-stabilizing circuit. The input end of the high-frequency push-pull inverter circuit is connected to a battery, the output end of the high-frequency push-pull inverter circuit is connected to the input end of the high-frequency transformer boost circuit, and the output end of the high-frequency transformer boost circuit is connected to the input end of the rectifier voltage-stabilizing circuit.

3. The portable electrolytic capacitor leakage current tester according to claim 1, It is characterized in that The electrolytic capacitor test circuit includes transistor Q1, transistor Q2, electrolytic capacitor CT, sampling resistor RIT, resistor R1, resistor R2, amplifier COMP1, and amplifier COMP2. The collector of transistor Q1 is connected to the positive output terminal of the DC-AC-DC circuit, the emitter of transistor Q1 is connected to one end of the electrolytic capacitor CT and one end of the resistor R1, the base of transistor Q1 is connected to the output terminal of amplifier COMP1 after level isolation, the in-phase terminal of amplifier COMP1 is connected to the single-chip microcomputer through the D / A conversion-1 circuit, and the The other end of the solution capacitor CT is connected to one end of the sampling resistor RIT and the input end of the amplifier A1, the other end of the sampling resistor RIT is connected to one end of the resistor R2 and the collector of the transistor Q2, the emitter of the transistor Q2 is connected to the negative electrode of the battery, the other end of the resistor R2 is connected to the other end of the resistor R1, the base of the transistor Q2 is connected to the output end of the amplifier COMP2 after level isolation, the in-phase end of the amplifier COMP2 is connected to the single-chip microcomputer through the D / A conversion-2 circuit, and the output end of the amplifier A1 is connected to the single-chip microcomputer through the A / D conversion circuit.

4. The portable electrolytic capacitor leakage current tester according to claim 3, It is characterized in that The electrolytic capacitor test circuit also includes a resistor R3 and a capacitor C3, one end of the resistor R3 is connected to the output end of the amplifier COMP1, the other end of the resistor R3 is connected to one end of the capacitor C3, and the other end of the capacitor C3 is connected to the other end of the resistor R1 and the inverting end of the amplifier COMP1.

5. The portable electrolytic capacitor leakage current tester according to claim 3, It is characterized in that The electrolytic capacitor test circuit also includes a resistor R4 and a capacitor C4, one end of the resistor R4 is connected to the output end of the amplifier COMP2, the other end of the resistor R4 is connected to one end of the capacitor C4, and the other end of the capacitor C4 is connected to the output end of the amplifier A1 and the inverting end of the amplifier COMP2.

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