Film capacitor aging accelerated continuous measurement and defect monitoring device and method

Abstract

The invention discloses a thin film capacitor aging accelerated continuous measurement and defect monitoring device and method, and belongs to the field of automatic measurement. The device comprises a power supply console, a control module, a current monitoring meter, a single-chip microcomputer controller, a multiplexer, an electrical parameter measuring instrument, an upper computer and a constant temperature and humidity chamber. A thin film capacitor test sample is placed in the constant temperature and humidity test box, the thin film capacitor test sample is connected with the power supply console and the control module, and a to-be-tested section of the thin film capacitor test sample is connected with the multiplexer; the control module periodically cuts off the connection between the thin film capacitor test sample and the power supply console / multiplexer; and the multiplexer is connected with the electrical parameter measuring instrument and is used for performing parameter measurement on the sample and sending parameter measurement data to the upper computer for storage. The current monitoring meter is connected with the test sample for current monitoring, and the single-chip microcomputer controller identifies the defective test sample through current data. And meanwhile, measurement of accelerated aging test data and defect monitoring are realized.

Description

Technical Field

[0001] The present invention belongs to the field of parameter measurement, and more specifically, relates to a device and method for accelerating continuous measurement and defect monitoring of film capacitor aging. Background Art

[0002] Film capacitors will gradually age during long-term operation. Aging will cause the electrical performance parameters of the capacitor components to change, thus threatening the normal operation of the entire system.

[0003] Generally, the natural aging time of capacitor components is long, and the accelerated aging test plays an important basic role in component performance evaluation, life prediction, reliability analysis and structural optimization design, and has been widely used. During the accelerated aging process, the capacitor must withstand harsh environments such as high temperature, high humidity, overvoltage, etc., in order to accelerate the aging process without completely damaging the component.

[0004] However, the traditional accelerated aging test method is discontinuous. During the test, it is necessary to pause the accelerated aging process before performing aging characterization, which takes a long time, and the long interruption may cause some electrical parameter values ​​to change within an unexpected range. At the same time, there are defective components in the aging process, which causes the capacitors that fail too early to instantly generate hundreds of degrees of high temperature, which will also be quickly transmitted to the adjacent capacitors through the common pole of the leads, causing the temperature of the adjacent capacitors to rise, the current to increase, and the breakdown or even combustion to occur. The smoke released by the combustion will contaminate the adjacent capacitors, resulting in more appearance waste. The production of defective products can only be interrupted and reloaded to eliminate them, which reduces the test efficiency. Therefore, there is an urgent need for a method that can continuously and automatically measure and monitor defects of the electrical parameters of thin film capacitors that can accelerate aging, which is of great significance to the accelerated aging test of thin film capacitors. Summary of the invention

[0005] In view of the defects of the related art, the purpose of the present invention is to provide a device and method for accelerated continuous measurement and defect monitoring of thin film capacitor aging, aiming to solve the problems of large numerical errors caused by discontinuity in traditional accelerated aging test methods and inability to effectively monitor defects.

[0006] To achieve the above-mentioned object, in a first aspect, the present invention provides a film capacitor aging accelerated continuous measurement and defect monitoring device, comprising: a power supply control console, a control module, a current monitoring meter, a single-chip controller, a multiplexer, an electrical parameter measuring instrument, a host computer and a constant temperature and humidity chamber;

[0007] When the device is working, a film capacitor test sample is placed in the constant temperature and humidity chamber, the film capacitor test sample is connected to the power control console and the control module, and the section to be tested of the film capacitor test sample is connected to the multiplexer; the constant temperature and humidity chamber is used to maintain the temperature and humidity of the environment where the film capacitor test sample is located; the power control console is used to apply voltage to the film capacitor test sample to perform an accelerated aging test;

[0008] The control module is used to receive instructions from the host computer and periodically disconnect the connection between the film capacitor test sample and the power console and the connection between the film capacitor test sample and the multiplexer;

[0009] The multiplexer is connected to an electrical parameter measuring instrument, which measures parameters of the film capacitor test sample and sends the parameter measurement data to the host computer for storage;

[0010] The current monitoring meter is connected to the section to be tested of the film capacitor test sample to monitor the current, and transmits the current data to the single-chip microcomputer controller for judgment to identify defective test samples.

[0011] Optionally, an LED light is provided on the single chip controller;

[0012] The single chip controller is used to control the LED light to sound an alarm when it determines that the current data is greater than a preset value.

[0013] Optionally, the device further comprises a circuit breaker;

[0014] The circuit breaker is connected to the single-chip controller and is used to disconnect the film capacitor test sample from the power supply console according to a control signal of the single-chip controller when the current data is greater than a preset value.

[0015] Optionally, the control module includes a PLC controller, a timer and a selection switch;

[0016] The PLC controller is connected to the host computer and the timer, and the timer is also connected to the selection switch, one end of the selection switch is connected to the film capacitor test sample and the power supply console, and the other end is connected to the film capacitor test sample and the multiplexer;

[0017] The PLC controller is used to receive instructions from the host computer and generate control signals;

[0018] The timer is used to start timing from the time the control signal is received, and within the set cycle T1 time, control the selection switch to connect the voltage source and the film capacitor test sample, and disconnect the multiplexer and the film capacitor test sample; after reaching the set cycle T1 time, control the selection switch to disconnect the voltage source and the film capacitor test sample, connect the multiplexer and the film capacitor test sample, and at the same time, reset the timer.

[0019] Optionally, the host computer is also used to determine whether the film capacitor test sample has reached the end of life condition, or whether the test time has reached T2 hours after receiving the parameter measurement data; if so, the host computer controls the end of the accelerated aging test.

[0020] Optionally, the host computer is further used to obtain a performance parameter curve of the film capacitor test sample according to the parameter measurement data after the accelerated aging test is completed.

[0021] Optionally, the constant temperature and humidity test box is provided with a wire outlet hole for leading out the sections to be tested of multiple film capacitor test samples through wires.

[0022] In a second aspect, the present invention further provides a method for continuous measurement and defect monitoring of film capacitor aging acceleration, which is applied to the device as described in any one of the first aspects, comprising:

[0023] Put the film capacitor test sample into a constant temperature and humidity test box, and adjust the temperature and humidity of the constant temperature and humidity test box to the set values; connect the film capacitor test sample to the power console and the control module, and connect the section to be tested of the film capacitor test sample to the multiplexer;

[0024] Sending instructions to the control module through the host computer to periodically disconnect the connection between the film capacitor test sample and the power console and the connection between the film capacitor test sample and the multiplexer;

[0025] The parameter measurement data of the film capacitor test sample is obtained from the host computer, and the defect monitoring result of the test sample is obtained from the single-chip microcomputer controller.

[0026] Compared with the prior art, the above technical solution conceived by the present invention can achieve the following beneficial effects:

[0027] 1. The present invention provides a film capacitor aging accelerated continuous measurement and defect monitoring device, which periodically controls the circuit connection at both ends of the film capacitor test sample through a control module, so that the film capacitor test sample is periodically and alternately connected to the power supply control console to apply voltage for accelerated aging test and connected to the multiplexer for parameter measurement, and the parameters of the film capacitor test element under test are continuously and automatically monitored during the accelerated aging test, eliminating the error caused by the interruption of the aging process, and greatly reducing the invalid time in the test. Further, the current of the test sample during the accelerated aging test is monitored by a current monitoring meter, and judgment is made based on this to identify defective test samples. It overcomes the problem that traditional aging methods cannot find defective products, and improves the reliability and yield of products. Placing the film capacitor test sample in a constant temperature and humidity test box can ensure the stability of the test conditions and is not affected by factors such as the external environment. The device provided by the present invention is safe and simple, the measurement method is convenient, the operability is strong, and the parameter test and defect monitoring results are highly accurate.

[0028] 2. The present invention provides a film capacitor aging accelerated continuous measurement and defect monitoring device, which realizes customized measurement time and interval thresholds by customizing the cycle of the timer in the control module to meet various test conditions.

[0029] 3. The present invention provides a device for accelerating continuous measurement and defect monitoring of film capacitor aging. An LED light is set on the single-chip microcomputer controller, and the LED light is used to light up an overcurrent warning lamp to realize timely alarm of defect monitoring. A circuit breaker connected to the single-chip microcomputer controller and the film capacitor test sample is set. When the film capacitor test sample is detected to be a defective sample, the circuit breaker is used to cut off the connection between the film capacitor test sample and the power supply console. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of a film capacitor aging accelerated continuous measurement and defect monitoring device provided by the present invention;

[0031] Figure 2 The present invention provides a flow chart of a method for continuous measurement and defect monitoring of film capacitor aging acceleration. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0033] The contents involved in the above embodiment are described below in conjunction with a preferred embodiment.

[0034] Embodiment 1

[0035] like Figure 1 As shown, the present invention provides a film capacitor aging accelerated continuous measurement and defect monitoring device, including: a power supply control console, a control module, a current monitoring meter, a single-chip controller, a multiplexer, an electrical parameter measuring instrument, a host computer and a constant temperature and humidity chamber;

[0036] When the device is working, a film capacitor test sample is placed in the constant temperature and humidity chamber, the film capacitor test sample is connected to the power control console and the control module, and the section to be tested of the film capacitor test sample is connected to the multiplexer; the constant temperature and humidity chamber is used to maintain the temperature and humidity of the environment where the film capacitor test sample is located; the power control console is used to apply voltage to the film capacitor test sample to perform an accelerated aging test;

[0037] The control module is used to receive instructions from the host computer and periodically disconnect the connection between the film capacitor test sample and the power console and the connection between the film capacitor test sample and the multiplexer;

[0038] The multiplexer is connected to an electrical parameter measuring instrument, which measures parameters of the film capacitor test sample and sends the parameter measurement data to the host computer for storage;

[0039] The current monitoring meter is connected to the section to be tested of the film capacitor test sample to monitor the current, and transmits the current data to the single-chip microcomputer controller for judgment to identify defective test samples.

[0040] In view of the problems existing in the existing thin film capacitor electrical parameter detection method and defect monitoring method, the embodiment of the present invention adopts a thin film capacitor aging accelerated continuous measurement and defect monitoring device to continuously and automatically monitor the thin film capacitor test samples, eliminate the errors caused by interruptions, and greatly reduce the invalid time in the test; at the same time, it overcomes the problem that the traditional aging method cannot find defective products, and improves the reliability and yield of the product.

[0041] A film capacitor aging accelerated continuous measurement and defect monitoring device provided in an embodiment of the present invention is constructed, and several film capacitor test samples of the same model are prepared. In this embodiment, the film capacitor test samples are film capacitor components; the initial performance parameters of the film capacitor components are measured, and the film capacitor test samples of the film capacitor components are placed in a constant temperature and humidity test box, and the temperature and humidity of the constant temperature and humidity test box are adjusted to the set values. The box body of the constant temperature and humidity test box is provided with a wire outlet hole, which is used to lead out the sections to be tested of multiple film capacitor test samples through wires. Connect the overall test circuit, start the host computer to send a test signal, and the power control console applies voltage to the film capacitor test sample to perform an accelerated aging test. The host computer sends a test signal to the control module, and periodically disconnects the connection between the film capacitor test sample and the power control console and the connection between the film capacitor test sample and the multiplexer; specifically, within the set period, the control module connects the power control console and the film capacitor test sample, and disconnects the film capacitor test sample and the multiplexer. At this time, the power control console continues to apply voltage to the film capacitor test sample for accelerated aging test; when the set period is reached, the control module disconnects the power control console and the film capacitor test sample, and connects the film capacitor test sample and the multiplexer. At this time, the multiplexer connects the sections to be tested of the film capacitor test sample one by one, and the electrical parameter measuring instrument connected thereto measures the parameters of the test sample, and sends the parameter measurement data to the host computer for storage; the continuous measurement of the parameters in the accelerated aging test of the film capacitor test sample is completed.

[0042] Among them, when measuring parameters, the multiplexer selects the sections to be tested of different film capacitor test samples one by one for connection, and multiple groups of data can be measured at one time to ensure the accuracy of the data.

[0043] Defect monitoring is carried out simultaneously during the accelerated aging test. The current monitoring meter is connected to the film capacitor test sample to monitor the current flowing through it in real time, and transmit the current data to the single-chip microcomputer controller for judgment. When the current flowing through a film capacitor test sample exceeds the set value A, the single-chip microcomputer controller determines that the sample has a defect.

[0044] Optionally, the control module includes a PLC controller, a timer and a selection switch;

[0045] The PLC controller is connected to the host computer and the timer, and the timer is also connected to the selection switch, one end of the selection switch is connected to the film capacitor test sample and the power supply console, and the other end is connected to the film capacitor test sample and the multiplexer;

[0046] The PLC controller is used to receive instructions from the host computer and generate control signals;

[0047] The timer is used to start timing from the time the control signal is received, and within the T1 time of the set cycle, control the selection switch to connect the voltage source and the film capacitor test sample, and disconnect the multiplexer and the film capacitor test sample; after reaching the T1 time of the set cycle, control the selection switch to disconnect the voltage source and the film capacitor test sample, and connect the multiplexer and the film capacitor test sample. At the same time, the timer is reset, and the next cycle measurement is performed without completing the test.

[0048] Optionally, an LED light is provided on the single chip controller;

[0049] The single chip controller is used to control the LED light to sound an alarm when it determines that the current data is greater than a preset value.

[0050] Optionally, the device further comprises a circuit breaker;

[0051] The circuit breaker is connected to the single-chip controller and is used to disconnect the film capacitor test sample from the power supply console according to a control signal of the single-chip controller when the current data is greater than a preset value.

[0052] During the defect monitoring process, the microcontroller controller with LED lights issues an overcurrent warning and lights up to indicate that the circuit breaker is disconnecting the circuit. After the circuit breaker cuts off the connection between the film capacitor test sample and the power console, the defective sample is taken out, the device is started again, and other samples are subjected to accelerated aging tests and defect monitoring.

[0053] Optionally, the host computer is also used to determine whether the film capacitor test sample has reached the end of life condition, or whether the test time has reached T2 hours after receiving the parameter measurement data; if so, the host computer controls the end of the accelerated aging test.

[0054] Optionally, the host computer is further used to obtain a performance parameter curve of the film capacitor test sample according to the parameter measurement data after the accelerated aging test is completed, and to perform a status evaluation and analysis on the film capacitor test sample.

[0055] In this embodiment, T1 is set to 30 minutes, and T2 is set to 500 hours.

[0056] In a specific embodiment, the capacitor elements used in the embodiments of the present invention have an initial capacitance of 500 μF, and there are 15 of them in total. The temperature of the constant temperature and humidity test chamber is set at 85°C, and the relative humidity is set at 85%. The cycle T1 is set to 30 minutes, and the end-of-life condition is when the capacitance decreases by more than 5% of the initial value. The cutoff time of the current monitoring table value is set to 0.6A, and this current value range is selected and set according to the capacitor specification requirements. Among them, a defective component is detected, an LED alarm is issued, and the circuit is cut off by the circuit breaker to remove the defective capacitor element. Finally, the upper computer obtains the curve of the percentage change of the capacitance decrease of the electronic components over time. Compared with the traditional accelerated aging method, the measurement cycle is improved from the previous day-level accuracy to the hour-level, and the defective film capacitor elements are accurately screened out.

[0057] The embodiment of the present invention periodically controls the circuit connection at both ends of the film capacitor test sample through a control module, so that the film capacitor test sample is periodically and alternately connected to the power supply control console to apply voltage for accelerated aging test and connected to the multiplexer for parameter measurement, and the parameters of the film capacitor test element under test are continuously and automatically monitored during the accelerated aging test, eliminating the error caused by the interruption of the aging process, and greatly reducing the invalid time in the test. Further, the current of the test sample during the accelerated aging test is monitored by a current monitoring table, and judgment is made based on this to identify defective test samples. It overcomes the problem that the traditional aging method cannot find defective products, and improves the reliability and yield of the product. Placing the film capacitor test sample in a constant temperature and humidity test box can ensure the stability of the test conditions and is not affected by factors such as the external environment. It solves the technical problems of large numerical errors caused by discontinuity in the traditional accelerated aging test method and the inability to effectively monitor defects, and achieves the beneficial effects of safety and simplicity, convenient measurement method, strong operability, and high accuracy of parameter testing and defect monitoring results.

[0058] Embodiment 2

[0059] The present invention further provides a method for continuous measurement and defect monitoring of film capacitor aging acceleration, which is applied to the device as described in any one of the first embodiments, comprising:

[0060] Put the film capacitor test sample into a constant temperature and humidity test box, and adjust the temperature and humidity of the constant temperature and humidity test box to the set values; connect the film capacitor test sample to the power console and the control module, and connect the section to be tested of the film capacitor test sample to the multiplexer;

[0061] Sending instructions to the control module through the host computer to periodically disconnect the connection between the film capacitor test sample and the power console and the connection between the film capacitor test sample and the multiplexer;

[0062] The parameter measurement data of the film capacitor test sample is obtained from the host computer, and the defect monitoring result of the test sample is obtained from the single-chip microcomputer controller.

[0063] A method for accelerating continuous measurement and defect monitoring of thin film capacitor aging provided by an embodiment of the present invention is implemented based on a device for accelerating continuous measurement and defect monitoring of thin film capacitor aging provided by any embodiment of the present invention, and has corresponding beneficial effects.

[0064] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A film capacitor aging accelerated continuous measurement and defect monitoring device, characterized in that: include: Power supply console, control module, current monitoring meter, single chip controller, multiplexer, electrical parameter measuring instrument, host computer and constant temperature and humidity chamber; When the device is working, a film capacitor test sample is placed in the constant temperature and humidity chamber, the film capacitor test sample is connected to the power control console and the control module, and the section to be tested of the film capacitor test sample is connected to the multiplexer; the constant temperature and humidity chamber is used to maintain the temperature and humidity of the environment where the film capacitor test sample is located; the power control console is used to apply voltage to the film capacitor test sample to perform an accelerated aging test; The control module is used to receive instructions from the host computer and periodically disconnect the connection between the film capacitor test sample and the power console and the connection between the film capacitor test sample and the multiplexer; The multiplexer is connected to an electrical parameter measuring instrument, which measures parameters of the film capacitor test sample and sends the parameter measurement data to the host computer for storage; The current monitoring meter is connected to the section to be tested of the film capacitor test sample to monitor the current, and transmits the current data to the single-chip microcomputer controller for judgment to identify defective test samples.

2. The device according to claim 1, characterized in that The single chip controller is provided with an LED lamp; The single chip controller is used to control the LED light to sound an alarm when it determines that the current data is greater than a preset value.

3. The device according to claim 2, characterized in that The device also includes a circuit breaker; The circuit breaker is connected to the single-chip microcomputer controller and is used to disconnect the film capacitor test sample from the power supply control console according to a control signal of the single-chip microcomputer controller when the current data is greater than a preset value.

4. The device according to claim 1, characterized in that The control module includes a PLC controller, a timer and a selection switch; The PLC controller is connected to the host computer and the timer, and the timer is also connected to the selection switch, one end of the selection switch is connected to the film capacitor test sample and the power supply console, and the other end is connected to the film capacitor test sample and the multiplexer; The PLC controller is used to receive instructions from the host computer and generate control signals; The timer is used to start timing from the receipt of the control signal, and control the selection switch to connect the voltage source and the film capacitor test sample, and disconnect the multiplexer and the film capacitor test sample within the set period T1 time; After reaching the set cycle T1 time, the selection switch is controlled to disconnect the voltage source and the film capacitor test sample, connect the multiplexer and the film capacitor test sample, and at the same time, the timer is reset.

5. The device according to claim 1, characterized in that The host computer is also used to determine whether the film capacitor test sample has reached the end of life condition or whether the test time has reached T2 hours after receiving the parameter measurement data; if so, the host computer controls the end of the accelerated aging test.

6. The device according to claim 5, characterized in that The host computer is also used to obtain the performance parameter curve of the film capacitor test sample according to the parameter measurement data after the accelerated aging test is completed.

7. The device according to claim 1, characterized in that The constant temperature and humidity test box is provided with a wire outlet hole on its box body, which is used to lead out the sections to be tested of multiple film capacitor test samples through wires.

8. A method for accelerating continuous measurement and defect monitoring of film capacitor aging, applied to the device as claimed in any one of claims 1 to 7, characterized in that: include: Put the film capacitor test sample into a constant temperature and humidity test box, and adjust the temperature and humidity of the constant temperature and humidity test box to the set values; connect the film capacitor test sample to the power console and the control module, and connect the section to be tested of the film capacitor test sample to the multiplexer; Sending instructions to the control module through the host computer to periodically disconnect the connection between the film capacitor test sample and the power console and the connection between the film capacitor test sample and the multiplexer; The parameter measurement data of the film capacitor test sample is obtained from the host computer, and the defect monitoring result of the test sample is obtained from the single-chip microcomputer controller.

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