Capacitance testing method and apparatus, computer readable recording medium

Abstract

A capacitor testing method and device, and a computer readable recording medium, the method is implemented by a capacitor testing device having a transformer, an AC signal generator, a variable error controller and a measuring instrument. The AC signal generator provides an AC signal to the transformer, the transformer outputs a test signal related to the AC signal to a capacitor to be tested, and the measuring instrument measures a measurement value related to the capacitor to be tested and provides the measurement value to the variable error controller. When the measurement value is less than a lower limit value, the variable error controller causes the AC signal generator to increase the power of the AC signal and accumulates the number of increases, and when the number of increases reaches a default value, the lower limit value is decreased. When the measurement value is greater than an upper limit value, the variable error controller causes the AC signal generator to decrease the power of the AC signal and accumulates the number of decreases, and when the number of decreases reaches the default value, the upper limit value is increased.

Description

Technical Field

[0001] This invention relates to a testing method for electronic components, and more particularly to a capacitance testing method. Background Technology

[0002] High-capacity capacitors, especially high-frequency capacitors, are always operated under high-frequency and high-voltage conditions during their development, manufacturing, and application. Therefore, in order to output high-voltage signals to the capacitors, transformers are often used for voltage and current boosting control.

[0003] Therefore, as Figure 1 As shown, a capacitance testing device 1 includes a transformer 11, an AC signal generator 12, a controller 13, and a voltmeter 14. The primary side 111 of the transformer 11 is electrically connected to the AC signal generator 12 to receive an AC signal generated by the AC signal generator 12, and outputs a test signal to a capacitor 2 under test that is electrically connected (in parallel) to the secondary side 112 of the transformer 11 according to the AC signal generator 12. The controller 13 is electrically connected to the AC signal generator 12, and the voltmeter 14 is electrically connected to the controller 13 and the capacitor 2 under test. The voltmeter 14 measures the voltage value across the capacitor 2 under test and provides the voltage value to the controller 13. The controller 13 determines whether the voltage value falls within an allowable range defined by a lower limit and an upper limit. If so, the controller 13 instructs the AC signal generator 12 to maintain (not adjust) the AC signal. If not, and the controller 13 determines that the voltage value is less than the lower limit, the controller 13 controls the AC signal generator 12 to increase (fine-tune) the input power (voltage and / or current) of the AC signal so that the voltage value of the capacitor under test 2 falls within the allowable range. Conversely, if the controller 13 determines that the voltage value is greater than the upper limit, the controller 13 controls the AC signal generator 12 to decrease the input power of the AC signal so that the voltage value of the capacitor under test 2 falls within the allowable range. This ensures that the voltage value of the capacitor under test 2 is maintained within a stable range during the test.

[0004] However, during the test, if the voltage value across the capacitor 2 under test is unstable and exceeds the allowable range due to environmental factors (for example, the frequency of the AC signal is such that the output inductive reactance of the transformer 11 (the inductive reactance of the secondary side 112) is equal to the capacitive reactance of the capacitor 2 under test, resulting in LC resonance), because the upper and lower limits defining the allowable range are fixed, even if the controller 13 continuously controls the AC signal generator 12 to increase or decrease the input power of the AC signal, the voltage value of the capacitor 2 under test will still fluctuate greatly due to the resonance phenomenon and cannot fall within the allowable range. As a result, during the entire test, the controller 13 must continuously control the AC signal generator 12 to increase or decrease the input power of the AC signal, but the voltage value of the capacitor 2 under test still cannot fall within the allowable range, and when this phenomenon (large fluctuations in the voltage value of the capacitor 2 under test) is displayed by the capacitor testing device 1, the tester will be doubtful about the displayed results and will not understand what is happening or will mistakenly think that the testing device is malfunctioning. SUMMARY

[0005] The present application aims to provide a capacitor testing method, a capacitor testing device implementing the method, and a computer-readable recording medium, which at least solve the problems of the prior art and enable the measured value of the capacitor under test to be maintained in a relatively stable state during the test.

[0006] The present application is a capacitor testing method implemented by a capacitor testing device. The capacitor testing device has a transformer, an AC signal generator, a variable error controller, and a measuring instrument. The AC signal generator is electrically connected to the primary side of the transformer to provide an AC signal to the transformer. The secondary side of the transformer is electrically connected to a capacitor under test to output a test signal related to the AC signal to the capacitor under test. The variable error controller is electrically connected to the AC signal generator and the measuring instrument. The measuring instrument is electrically connected to the capacitor under test to measure a measured value related to the capacitor under test. The method includes the following steps.

[0007] Step (A): When the variable error controller obtains the measured value measured by the measuring instrument and determines that a test time has not ended and that the measured value is less than a lower limit value, step (B) is performed, or when the measured value is greater than an upper limit value, step (C) is performed; wherein the lower limit value and the upper limit value define an allowable range, and the upper limit value is a target value plus an error value, and the lower limit value is the target value minus the error value.

[0008] Step (B): the variable error controller instructs the AC signal generator to increase the input power of the AC signal and accumulates a number of increases, and when the variable error controller determines that the number of increases reaches a default value, the variable error controller increases the error value and resets the number of increases, and then repeats step (A).

[0009] Step (C): the variable error controller instructs the AC signal generator to decrease the input power of the AC signal and accumulates a number of decreases, and when the variable error controller determines that the number of decreases reaches the default value, the variable error controller increases the error value and resets the number of decreases, and then repeats step (A).

[0010] In some embodiments of the present application, in step (A), when the variable error controller determines that the measured value falls within the allowable range, the variable error controller instructs the AC signal generator to maintain the input power of the AC signal, and then repeats step (A); in step (B), when the variable error controller determines that the number of increases does not reach the default value, the variable error controller repeats step (A); in step (C), when the variable error controller determines that the number of decreases does not reach the default value, the variable error controller repeats step (A).

[0011] In some embodiments of the present application, in step (A), when the variable error controller determines that the test time is over, the capacitance testing device displays the error value.

[0012] In some embodiments of the present application, the input power of the AC signal is voltage and / or current, the measuring instrument is a voltmeter and / or an ammeter, and the measured value is the voltage across the capacitor under test and / or the current flowing through the capacitor under test.

[0013] In some embodiments of the present application, the error value is N% of the target value, and each time the variable error controller increases the error value, the variable error controller increases the error value to (N+M*C) % of the target value, where N and M are real numbers greater than 0, and C is the number of times the error value is increased.

[0014] In addition, the present application provides a computer-readable recording medium storing a software program, wherein the software program is loaded and executed by a capacitance testing device, and the capacitance testing device is capable of performing the capacitance testing method as described above.

[0015] The beneficial effect of the present application is that during the testing of the capacitor, when the variable error controller determines that the number of times the input power of the AC signal is increased or decreased reaches the default value, the error value is increased to timely expand the allowable range determined by the error value, so that the measured value of the capacitor under test can fall within the allowable range, and the variable error controller does not need to repeatedly increase or decrease the input power of the AC signal, so that the measured value of the capacitor under test can be maintained within a stable range during testing, so that when the capacitor testing device displays the measured value of the capacitor under test, the tester will not doubt the display result or mistakenly think that the testing device is malfunctioning. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a block diagram of the components of a conventional capacitor testing device.

[0017] Figure 2 is the main flow steps of an embodiment of the capacitor testing method of the present application.

[0018] Figure 3 is a block diagram of the components of an embodiment of the capacitor testing device of the present application.

[0019] Figure 4 shows the additional steps of the present embodiment between steps S25 and S26 of Figure 2 .

[0020] Figure 5 shows the additional steps of the present embodiment between steps S28 and S29 of Figure 2 . DETAILED DESCRIPTION

[0021] The present application will be described in detail below with reference to the accompanying drawings and embodiments.

[0022] Before the present application is described in detail, it should be noted that like components are denoted by like numbers in the following description.

[0023] Referring to Figure 2 , shown is the main flow of an embodiment of the capacitor testing method of the present application, which is applied to Figure 3 , shown is a capacitor testing device 3 of the present application. As Figure 3As shown, the capacitor testing device 3 has a transformer 31, an AC signal generator 32, a variable error controller 33 and a measuring instrument 34. The AC signal generator 32 is electrically connected to a primary side 311 of the transformer 31 to provide an AC signal to the transformer 31, and a secondary side 312 of the transformer 31 is electrically connected to a capacitor under test 4 to output a testing signal related to the AC signal to the capacitor under test 4, i.e. the testing signal is the AC signal after being stepped up in voltage and / or current by the transformer 31, so that the testing signal can provide high voltage and / or high current to the capacitor under test 4.

[0024] The variable error controller 33 is electrically connected to the AC signal generator 32 and the measuring instrument 34 to receive a measurement value outputted by the measuring instrument 34 and to control the AC signal generated by the AC signal generator 32. The measuring instrument 34 is electrically connected to the capacitor under test 4 to measure a measurement value related to the capacitor under test 4; specifically, the measuring instrument 34 can be a voltmeter to measure the voltage across the capacitor under test 4 and / or an ammeter to measure the current flowing through the capacitor under test 4, so that the measurement value outputted by the measuring instrument 34 can be the voltage value across the capacitor under test 4 and / or the current value flowing through the capacitor under test 4. In the present embodiment, the measuring instrument 34 is taken as an example of a voltmeter.

[0025] Moreover, a computer-readable recording medium (e.g. a memory unit) of the capacitor testing device 3 stores a software program, which is loaded and executed by the variable error controller 33 (e.g. a central processing unit, a microprocessor or a microcontroller) to cause the variable error controller 33 to perform the following flow: Figure 2

[0026] As shown in the flow of the method for testing the capacitor under test 4, the present embodiment performs the following steps S21-S23: Figure 2 Figure 2 When the variable error controller 33 acquires the measurement value (voltage value) measured by the measuring instrument (voltmeter) 34 at a default sampling frequency, e.g. 1 Hz, the variable error controller 33 first determines whether a testing time, e.g. 8 hours, is over, and if not, proceeds to step S23 to determine whether the measurement value is within a tolerance range defined by a lower limit value and an upper limit value, wherein the upper limit value is a target value plus an error value, and the lower limit value is the target value minus the error value, the target value is the expected voltage value of the capacitor under test 4, and the error value is N% of the target value, N being a real number greater than 0, e.g. 0.5, 1, 2, 3, 3.5, etc. Figure 2

[0027] ​​​Therefore, in step S23, if the variable error controller 33 determines that the measured value is within the allowable range, it means that the voltage value (measured value) of the capacitor under test 4 is in a stable state and there is no need to adjust the AC signal input to the transformer 31. Then the variable error controller 33 returns to step S21 and repeats steps S21 to S23.

[0028] In step S23, if the variable error controller 33 determines that the measured value is less than the lower limit, it means that the input power of the AC signal is insufficient to make the voltage value across the capacitor 4 under test fall within the allowable range. Therefore, as shown in step S24, the variable error controller 33 causes the AC signal generator to increase (fine-tune) the input power of the AC signal input to the transformer 31 (for example, fine-tune the voltage and / or current of the AC signal), and accumulates the number of increases.

[0029] Then, as shown in step S25, the variable error controller 33 first determines whether the cumulative number of adjustments has reached a default value X (X is, for example, but not limited to, 5 times). If not (for example, only 1 adjustment), it returns to step S21 and repeats steps S21 to S23. If steps S21 to S23 are repeated several times and step S24 is repeated several times, when the variable error controller 33 determines in step S25 that the number of adjustments has reached the default value X, it means that even if the input power of the AC signal is increased multiple times, the voltage value generated by the capacitor under test 4 cannot fall within the allowable range. Therefore, it is necessary to expand the allowable range so that the voltage value generated by the capacitor under test 4 falls within the allowable range. The variable error controller 33 does not need to repeat step S24 (increase the input power of the AC signal) repeatedly and keeps the voltage value generated by the capacitor under test 4 in a stable state as much as possible during the test.

[0030] Therefore, as Figure 2 In step S26, the variable error controller 33 increases the error value, for example, by increasing the error value to (N+M*C)% of the target value, where M is a real number greater than 0 and C is the number of times the error value is increased. For example, if M=1 and C=1 is the first time the error value is increased, then the error value is increased to (N+1*1)% of the target value. The lower limit will then become the target value minus the increased error value (i.e., the target value multiplied by (N+1)%), and the upper limit will become the target value plus the increased error value (i.e., the target value multiplied by (N+1)%), thus expanding the allowable range. Furthermore, the variable error controller 33 resets the accumulated number of increases to zero and then returns to step S21, repeating steps S21 to S23.

[0031] Afterwards, when the variable error controller 33 executes step S25 during the test, if it is determined again that the accumulated number of increases reaches the default value X, step S26 is executed again to increase the error value again (at this time, C=2, the error value is increased to (N+1*2)% of the target value); that is, as long as the accumulated number of increases reaches the default value X again, the variable error controller 33 will increase the error value again. In addition, in another embodiment, when the variable error controller 33 determines that the error value has reached a preset limit value and cannot be increased any more, even if the accumulated number of increases reaches the default value X again, the variable error controller 33 will maintain the error value at the limit value. Therefore, in another embodiment, as shown in FIG. 8, a step S251 can be added between step S25 and step S26 to determine first whether the error value has reached the preset limit value. If not, step S26 is executed again. If yes, step S252 is executed to maintain the error value at the limit value, and then return to step S21. Figure 4

[0032] Returning to step S23, if the variable error controller 33 determines that the measured value is greater than the upper limit value, it indicates that the input power of the AC signal is too large so that the voltage value generated by the capacitor under test 4 exceeds the allowable range. Therefore, as shown in step S27, the variable error controller 33 causes the AC signal generator to decrease (fine tune) the input power of the AC signal to the transformer 31 (for example, fine tune the voltage and / or current of the AC signal), and accumulates the number of decreases.

[0033] Then, as shown in step S28, the variable error controller 33 determines first whether the accumulated number of decreases has reached the default value X (X is for example but not limited to 5 times). If not (for example, only 1 time), return to step S21 to repeat steps S21-S23. If steps S21-S23 are repeated several times and step S27 is repeated several times, the variable error controller 33 determines in step S28 that the number of decreases has reached the default value X, which indicates that even if the input power of the AC signal is decreased several times, the voltage value generated by the capacitor under test 4 still cannot fall within the allowable range. Therefore, it is necessary to expand the allowable range so that the voltage value generated by the capacitor under test 4 falls within the allowable range. The variable error controller 33 does not need to repeat step S27 (decrease the input power of the AC signal) again, and the voltage value generated by the capacitor under test 4 is maintained as stable as possible during the test.

[0034] Therefore, as shown in FIG. 9, a step S271 can be added between step S27 and step S28 to determine first whether the measured value has reached the limit value. If not, step S28 is executed again. If yes, step S272 is executed to maintain the measured value at the limit value, and then return to step S21. Figure 2 ​the error value is adjusted to (N+M*C) % of the target value, for example, if M = 1 and the error value is adjusted for the third time, C = 3, the error value is adjusted to (N+1*3) % of the target value, then the lower limit value becomes the target value minus the adjusted error value (i.e., the target value multiplied by (N+3) %), and the upper limit value becomes the target value plus the adjusted error value (i.e., the target value multiplied by (N+3) %), thus expanding the allowable range. Also, the variable error controller 33 resets the accumulated number of adjustments and returns to step S21 to repeat steps S21-S23.

[0035] Similarly, later in the test, when the variable error controller 33 executes step S28, if it is determined again that the accumulated number of adjustments reaches the default value X, step S29 is executed again to adjust the error value again (at this time, C = 4, the error value is adjusted to (N+1*4) % of the target value); that is, as long as the accumulated number of adjustments reaches the default value X again, the variable error controller 33 adjusts the error value again. Similarly, in another embodiment, when the variable error controller 33 determines that the error value has reached the preset limit value and cannot be adjusted upward any more, even if the accumulated number of adjustments reaches the default value X again, the variable error controller 33 maintains the error value at the limit value. Therefore, in another embodiment, as shown in FIG. 3, a step S281 can be added between step S28 and step S29 to first determine whether the error value has reached the preset limit value, if not, step S29 is executed again, if yes, step S282 is executed to maintain the error value at the limit value, and then returns to step S21. Figure 5

[0036] As can be seen from the above description, in the test, whether the input power of the AC signal is adjusted upward or downward, as long as the accumulated number of upward adjustments or the accumulated number of downward adjustments reaches the default value X, the error value is adjusted once, so if the initial error value is 1 % of the target value (i.e., N = 1), and it is assumed that M = 1, i.e., each time the error value is adjusted by adding 1 % of the target value to the error value, and it is assumed that in the entire test, the accumulated number of upward adjustments reaches the default value X for 2 times, and the accumulated number of downward adjustments reaches the default value X for 3 times, C = 5, then the error value is adjusted to 6 % of the target value, thus the lower limit value becomes the target value minus 6 % of the target value (the adjusted error value), and the upper limit value becomes the target value plus 6 % of the target value (the adjusted error value).

[0037] ​Furthermore, when the variable error controller 33 judges that the test time is over in step S22, step S30 is performed to make the capacitor testing device 3 display the final error value, for example, 4% (known target value) or 4% of the target value in the above example.

[0038] In summary, in the process of testing the capacitor, the above embodiment judges that the number of times of increasing or decreasing the input power of the AC signal reaches the default value X by the variable error controller 33, i.e. increasing the error value, to timely expand the allowable range determined by the error value, so that the voltage value generated by the capacitor under test 4 can fall within the allowable range, and the variable error controller 33 does not need to repeatedly increase or decrease the input power of the AC signal, so that the voltage value generated by the capacitor under test 4 can be maintained in a stable range as much as possible during the test process. When the capacitor testing device 3 displays the voltage value of the capacitor under test 4, the tester will not doubt the display result or mistakenly think that the testing device is malfunctioning. After the test is completed, the capacitor testing device 3 displays the final error value for the tester to refer to, which truly achieves the effect and purpose of the present application.

Claims

1. A method for testing a capacitor, applied to a capacitor testing device having a transformer, an AC signal generator, a variable error controller and a measuring instrument, the AC signal generator being electrically connected to a primary side of the transformer to provide an AC signal to the transformer, a secondary side of the transformer being electrically connected to a capacitor under test to output a test signal related to the AC signal to the capacitor under test, the variable error controller being electrically connected to the AC signal generator and the measuring instrument, the measuring instrument being electrically connected to the capacitor under test to measure a measured value related to the capacitor under test; the method comprising: (A) the variable error controller obtaining the measured value measured by the measuring instrument, and determining that a test time has not ended, and determining that the measured value is less than a lower limit value, then performing step (B), or determining that the measured value is greater than an upper limit value, then performing step (C); wherein the lower limit value and the upper limit value define a permitted range, and the upper limit value is a target value plus an error value, and the lower limit value is the target value minus the error value; (B) the variable error controller causing the AC signal generator to increase the input power of the AC signal and accumulate an increase count, and the variable error controller determining that the increase count reaches a default value, then the variable error controller increases the error value and resets the increase count to zero, and then repeating step (A); and (C) the variable error controller causing the AC signal generator to decrease the input power of the AC signal and accumulate a decrease count, and the variable error controller determining that the decrease count reaches the default value, then the variable error controller increases the error value and resets the decrease count to zero, and then repeating step (A). In step (A), the variable error controller determines that the measured value falls within the permitted range, causing the AC signal generator to maintain the input power of the AC signal, and repeating step (A); in step (B), the variable error controller determines that the increase count does not reach the default value, and repeating step (A); in step (C), the variable error controller determines that the decrease count does not reach the default value, and repeating step (A).

2. The method of claim 1, wherein: In step (A), the variable error controller determines that the test time ends, causing the capacitor testing device to display the error value.

3. The method of claim 1, wherein: The input power of the AC signal is voltage and / or current, the measuring instrument is a voltmeter and / or an ammeter, and the measured value is the voltage value across the capacitor under test and / or the current value flowing through the capacitor under test.

4. The method of claim 1, wherein: The error value is N% of the target value, and each time the variable error controller increases the error value, the error value is increased to (N+M*C)% of the target value, wherein N and M are real numbers greater than 0, and C is the number of times the error value is increased.

5. The method of claim 1, wherein:

6. A capacitor testing device for testing a capacitor under test, the capacitor testing device comprising: a transformer, a secondary side of the transformer being electrically connected to the capacitor under test; an AC signal generator, electrically connected to a primary side of the transformer to provide an AC signal to the transformer, so that the transformer outputs a test signal related to the AC signal to the capacitor under test; ​ ​ a variable error controller electrically connected to the AC signal generator; and a measuring instrument electrically connected to the variable error controller and electrically connected to the capacitor under test, to measure a measured value related to the capacitor under test; and the variable error controller performs the following steps: Step (A): the variable error controller acquires the measured value measured by the measuring instrument, and judges that a test time has not ended, and judges that the measured value is less than a lower limit value, then proceeds to Step (B), or judges that the measured value is greater than an upper limit value, then proceeds to Step (C); wherein the lower limit value and the upper limit value define an allowable range, and the upper limit value is a target value plus an error value, and the lower limit value is the target value minus the error value; Step (B): the variable error controller causes the AC signal generator to increase the input power of the AC signal, and accumulates an increase count, and the variable error controller judges that the increase count reaches a default value, then the variable error controller increases the error value and resets the increase count, and repeats Step (A); and Step (C): the variable error controller causes the AC signal generator to decrease the input power of the AC signal and accumulates a decrease count, and the variable error controller judges that the decrease count reaches the default value, then the variable error controller increases the error value and resets the decrease count, and repeats Step (A).

7. The capacitance testing device of claim 6, wherein: In Step (A), the variable error controller judges that the measured value falls within the allowable range, causes the AC signal generator to maintain the input power of the AC signal, and repeats Step (A); in Step (B), the variable error controller judges that the increase count does not reach the default value, and repeats Step (A); in Step (C), the variable error controller judges that the decrease count does not reach the default value, and repeats Step (A).

8. The capacitance testing device of claim 6, wherein: In Step (A), the variable error controller judges that the test time ends, causes the capacitor testing device to display the error value.

9. The capacitance testing device of claim 6, wherein: The input power of the AC signal is voltage and / or current, the measuring instrument is a voltmeter and / or an ammeter, and the measured value is the voltage value across the capacitor under test and / or the current value flowing through the capacitor under test.

10. The capacitance testing device of claim 6, wherein: The error value is N% of the target value, and each time the variable error controller increases the error value, the error value is increased to (N+M*C)% of the target value, wherein N and M are real numbers greater than 0, and C is the number of times of increasing the error value.

11. A computer-readable recording medium, wherein a software program is stored, and after the software program is loaded and executed by a capacitor testing device, the capacitor testing device can perform the capacitor testing method according to any one of claims 1 to 5.

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