Capacitance test method and device, and computer readable recording medium

Abstract

A capacitance testing method and apparatus, and a computer readable recording medium, the method being implemented by a capacitance testing apparatus having a transformer, an AC signal generator, a variable error controller, and a measuring instrument, the AC signal generator providing an AC signal to the transformer, the transformer outputting a test signal related to the AC signal to a capacitor to be tested, and the variable error controller outputting a test signal related to the test signal to the capacitor to be tested. The measuring instrument measures a measured value related to the capacitor to be measured and provides the measured value to the variable error controller; when the variable error controller judges that the measured value is smaller than a lower limit value, the alternating current signal generator raises the alternating current signal power and accumulates the ramping frequency, and when the ramping frequency reaches a default value, the lower limit value is lowered; when the variable error controller judges that the measured value is larger than an upper limit value, the alternating current signal generator reduces the power of the alternating current signal and accumulates the number of times of reduction, and when the number of times of reduction reaches a default value, the variable error controller increases the upper limit value.

Description

Technical Field

[0001] The present invention relates to a method for testing electronic components, and particularly to a method for testing capacitors. Background Art

[0002] For high-capacity capacitors, especially high-frequency capacitors, during development, manufacturing, and application, they must operate under high-frequency and high-voltage conditions. Therefore, in order to output a high-voltage signal to the capacitor, a transformer is often used to control step-up voltage and step-up current.

[0003] Therefore, as Figure 1 shown, there is a conventional capacitor testing device 1 including 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 under test 2 electrically connected (in parallel) to the secondary side 112 of the transformer 11. 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 under test 2. It measures the voltage value across the capacitor under test 2 and provides the voltage value to the controller 13. The controller 13 determines whether the voltage value is within a tolerance range defined by a lower limit value and an upper limit value. If so, the controller 13 instructs the AC signal generator 12 to maintain (without adjustment) the AC signal. If not, and the controller 13 determines that the voltage value is less than the lower limit value, 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 can fall within the tolerance range. And if the controller 13 determines that the voltage value is greater than the upper limit value, 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 can fall within the tolerance range. Thereby, the voltage value of the capacitor under test 2 can be maintained within a stable range during the testing process.

[0004] However, during the testing process, if the voltage value across the capacitor 2 to be tested is in an unstable state and exceeds the allowable range due to environmental factors (for example, when the frequency of the AC signal makes the output inductive reactance (the inductive reactance of the secondary side 112 inductor) of the transformer 11 equal to the capacitive reactance of the capacitor 2 to be tested and LC resonance occurs), since the upper limit value and the lower limit value 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 to be tested will still experience large fluctuations up and down due to the above resonance phenomenon and still cannot fall within the allowable range. As a result, during the entire testing process, 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 to be tested still cannot fall within the allowable range. When this phenomenon (the large fluctuations in the voltage value of the capacitor 2 to be tested) is displayed by the capacitor testing device 1, it will cause the tester to have doubts about the display result and not understand what is happening or mistakenly think that the testing device is malfunctioning. Summary of the Invention

[0005] The object of the present invention is to provide a capacitance testing method, a capacitance testing device for implementing the method, and a computer-readable recording medium, which can at least solve the problems of the prior art and enable the measured value of the capacitor to be detected to maintain a relatively stable state during the testing process.

[0006] A capacitance testing method of the present invention is implemented by a capacitance testing device of the present invention. The capacitance 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 to be tested to output a test signal related to the AC signal to the capacitor to be tested. 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 to be tested to measure a measured value related to the capacitor to be tested. The method includes the following steps.

[0007] Step (A): When the variable error controller obtains the measured value measured by the measuring instrument, determines that a test time has not ended, and determines that the measured value is less than a lower limit value, it proceeds to step (B), or when it determines that the measured value is greater than an upper limit value, it 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.

[0008] Step (B): The variable error controller commands the AC signal generator to increase the input power of the AC signal and accumulates an increasing times. When the variable error controller determines that the increasing times reaches a default value, the variable error controller increases the error value, resets the increasing times to zero, and then repeats step (A).

[0009] Step (C): The variable error controller commands the AC signal generator to decrease the input power of the AC signal and accumulates a decreasing times. When the variable error controller determines that the decreasing times reaches the default value, the variable error controller increases the error value, resets the decreasing times to zero, and then repeats step (A).

[0010] In some embodiments of the present invention, in step (A), when the variable error controller determines that the measured value falls within the allowable range, it commands the AC signal generator to maintain the input power of the AC signal and repeats step (A); in step (B), when the variable error controller determines that the increasing times has not reached the default value, it repeats step (A); in step (C), when the variable error controller determines that the decreasing times has not reached the default value, it repeats step (A).

[0011] In some embodiments of the present invention, in step (A), when the variable error controller determines that the test time ends, it commands the capacitance test device to display the error value.

[0012] In some embodiments of the present invention, 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 capacitance to be measured and / or the current value flowing through the capacitance to be measured.

[0013] In some embodiments of the present invention, the error value is N% of the target value, and each time the variable error controller increases the error value, it 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 of increasing the error value.

[0014] In addition, a computer-readable recording medium of the present invention stores a software program. After the software program is loaded and executed by a capacitance test device, the capacitance test device can complete the capacitance test method as described above.

[0015] The beneficial effects of the present invention are as follows: During the process of testing a 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 to be tested 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. The measured value of the capacitor to be tested can be maintained within a stable range as much as possible during the testing process, so that when the capacitor testing device displays the measured value of the capacitor to be tested, it will not cause doubts for the tester or mistakenly think that the testing device is faulty. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

[0019] Figure 4 Show the additional steps between Figure 2 step S25 and step S26 of this embodiment.

[0020] Figure 5 Show the additional steps between Figure 2 step S28 and step S29 of this embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

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

[0022] Before the present invention is described in detail, it should be noted that in the following description, similar components are denoted by the same reference numerals.

[0023] Refer to Figure 2 shown, which is the main flow of an embodiment of a capacitor testing method of the present invention, and it is applied to Figure 3 a capacitor testing device 3 of the present invention shown in Figure 3As shown, the capacitance testing device 3 includes 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 the primary side 311 of the transformer 31 to provide an AC signal to the transformer 31. The secondary side 312 of the transformer 31 is electrically connected to a capacitor under test 4 to output a test signal related to the AC signal to the capacitor under test 4. That is, the test signal is the AC signal after the AC signal is stepped up in voltage and / or increased in current by the transformer 31, so that the test 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 output by the measuring instrument 34 and 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 for measuring the voltage across the capacitor under test 4 and / or an ammeter for measuring the current flowing through the capacitor under test 4. Therefore, the measurement value output 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 this embodiment, the measuring instrument 34 is taken as an example of a voltmeter.

[0025] And a computer-readable recording medium (such as a memory unit) in the capacitance testing device 3 stores a software program. After the software program is loaded and executed by the variable error controller 33 (such as a central processing unit, a microprocessor, or a microcontroller, etc.), the variable error controller 33 will execute Figure 2 the process as described below.

[0026] As Figure 2 shown in the process, the method for testing the capacitor under test 4 in this embodiment is as follows. In step S21 as shown in Figure 2 , when the variable error controller 33 obtains the measurement value (voltage value) measured by the measuring instrument (voltmeter) 34 for the capacitor under test 4 at a default sampling frequency, such as 1 Hz, in step S22 as shown in Figure 2 , the variable error controller 33 first determines whether a test time, such as 8 hours, has ended. If not, it proceeds to step S23. The variable error controller 33 determines whether the measurement value is within a tolerance range defined by a lower limit value and an upper limit value. Among them, the upper limit value is a target value plus an error value, the lower limit value is the target value minus the error value, the target value is the voltage value expected (desired) for the capacitor under test 4, and the error value is N% of the target value, where N is a real number greater than 0, such as 0.5, 1, 2, 3, 3.5, etc.

[0027] Therefore, in step S23, if the variable error controller 33 determines that the measured value is within the allowable range, it indicates that the voltage value (the measured value) of the capacitor 4 to be measured changes 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 - S23.

[0028] If in step S23 the variable error controller 33 determines that the measured value is less than the lower limit value, it indicates that the input power of an AC signal is not sufficient to make the voltage value across the capacitor 4 to be measured fall within the allowable range. Therefore, as shown in step S24, the variable error controller 33 instructs 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 accumulated number of increases has reached a default value X (X is, for example but not limited to, 5 times). If not (for example, only increased once), it returns to step S21 and repeats steps S21 - S23. After repeating steps S21 - S23 several times and repeating step S24 several times, when the variable error controller 33 determines in step S25 that the number of increases has reached the default value X, it indicates that even after increasing the input power of the AC signal multiple times, the voltage value generated by the capacitor 4 to be measured 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 4 to be measured falls within the allowable range. The variable error controller 33 does not need to repeatedly repeat step S24 (increase the input power of the AC signal), and tries to keep the voltage value of the capacitor 4 in a stable state during the test process.

[0030] Therefore, as Figure 2 in step S26, the variable error controller 33 increases the error value. For example, it increases 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 the error value is increased for the first time (C = 1), then the error value is increased to (N + 1 * 1)% of the target value. Then the lower limit value will become the target value minus the increased error value (i.e., the target value multiplied by (N + 1)%), and the upper limit value will become the target value plus the increased error value (i.e., the target value multiplied by (N + 1)%), thus expanding the allowable range. And the variable error controller 33 resets the accumulated number of increases to zero, then returns to step S21 and repeats steps S21 - S23.

[0031] After that, during the testing process, when the variable error controller 33 executes step S25, if it is determined again that the accumulated number of upward adjustments reaches the default value X, then step S26 is executed again to increase the error value again (at this time C = 2, and the error value is increased to (N + 1 * 2)% of the target value); that is, as long as the accumulated number of upward adjustments 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 further, even if the accumulated number of upward adjustments 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 Figure 4 shown, a step S251 can be added between step S25 and step S26. First, it is determined whether the error value has reached the preset limit value. If not, then step S26 is executed. If so, then step S252 is executed to maintain the error value at the limit value, and then return to step S21.

[0032] Returning to step S23 again, if the variable error controller 33 determines that the measured value is greater than the upper limit value, it means 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 commands the AC signal generator to decrease (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 downward adjustments.

[0033] Then, as shown in step S28, the variable error controller 33 first determines whether the accumulated number of downward adjustments has reached the default value X (X is, for example, but not limited to, 5 times). If not (for example, only adjusted upward once), then return to step S21 and repeat steps S21 - S23; and if steps S21 - S23 are repeated several times and step S27 is repeated several times, when the variable error controller 33 determines in step S28 that the number of downward adjustments has reached the default value X, it means that even if the input power of the AC signal is adjusted downward multiple 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 repeatedly execute step S27 (decrease the input power of the AC signal) and tries to keep the voltage value of the capacitor under test 4 as stable as possible during the testing process.

[0034] Therefore, as Figure 2In step S29, the variable error controller 33 increases the error value. For example, as described above, the error value is increased to (N + M * C)% of the target value. For instance, if M = 1 and the error value is increased for the third time with C = 3, the error value is increased to (N + 1 * 3)% of the target value. Then, the lower limit value will become the target value minus the increased error value (i.e., the target value multiplied by (N + 3)%), and the upper limit value will become the target value plus the increased error value (i.e., the target value multiplied by (N + 3)%), thus expanding the allowable range. Moreover, the variable error controller 33 resets the accumulated number of downward adjustments to zero and then returns to step S21 to repeat steps S21 - S23.

[0035] Similarly, afterwards, during the testing process, when the variable error controller 33 reaches step S28, if it determines again that the accumulated number of downward adjustments reaches the default value X, it will execute step S29 again to increase the error value again (at this time C = 4, and the error value is increased to (N + 1 * 4)% of the target value); that is, as long as the accumulated number of downward adjustments reaches the default value X again, the variable error controller 33 will increase 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 increased further, even if the accumulated number of downward adjustments 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 Figure 5 shown, a step S281 can be added between step S28 and step S29. First, it is determined whether the error value has reached the preset limit value. If not, step S29 is executed. If so, step S282 is executed to maintain the error value at the limit value and then return to step S21.

[0036] From the above description, it can be seen that during the testing process, whether increasing or decreasing the input power of the AC signal, as long as the accumulated number of upward adjustments or the accumulated number of downward adjustments reaches the default value X, the error value will be increased once. Therefore, if the initial error value is 1% of the target value (i.e., N = 1), and assuming M = 1, that is, each time the error value is increased by adding 1% of the target value, and assuming that during the entire testing process, the accumulated number of upward adjustments reaches the default value X 2 times and the accumulated number of downward adjustments reaches the default value X 3 times, with C = 5, then the error value is increased to 6% of the target value. Thus, the lower limit value becomes the target value minus 6% of the target value (the increased error value), and the upper limit value becomes the target value plus 6% of the target value (the increased error value).

[0037] Furthermore, in step S22, when the variable error controller 33 determines that the test time has ended, step S30 is executed to cause the capacitance testing device 3 to display the final error value. Taking the above example, it is 4% (given the target value) or 4% of the target value.

[0038] In summary, during the process of testing the capacitance in the above embodiments, when the variable error controller 33 determines that the number of times the input power of the AC signal is increased or decreased reaches the default value X, the error value is increased in a timely manner to appropriately expand the allowable range determined by the error value, so that the voltage value generated by the capacitance 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, and the voltage value generated by the capacitance under test 4 can be maintained within a stable range as much as possible during the test process. When the capacitance testing device 3 displays the voltage value of the capacitance under test 4, it does not cause doubts or misunderstandings about the test result by the tester, and after the test is completed, the capacitance testing device 3 is caused to display the final error value for the tester's reference, thus truly achieving the effects and purposes of the present invention.

Claims

1. A capacitance testing method is applied to a capacitance testing device. The capacitance 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 capacitance under test to output a test signal related to the AC signal to the capacitance 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 capacitance under test to measure a measured value related to the capacitance under test; Characterized in that: The method includes: 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 determines that the measured value is less than a lower limit value, step (B) is performed, or when it determines that 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; Step (B): The variable error controller causes the AC signal generator to increase the input power of the AC signal and accumulates an increasing number of times. When the variable error controller determines that the increasing number of times reaches a default value, the variable error controller increases the error value and resets the increasing number of times to zero, and then 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 decreasing number of times. When the variable error controller determines that the decreasing number of times reaches the default value, the variable error controller increases the error value and resets the decreasing number of times to zero, and then repeats step (A).

2. The capacitance testing method according to claim 1, Characterized in that: In step (A), when the variable error controller determines that the measured value falls within the allowable range, it causes the AC signal generator to maintain the input power of the AC signal and repeats step (A); in step (B), when the variable error controller determines that the increasing number of times does not reach the default value, it repeats step (A); in step (C), when the variable error controller determines that the decreasing number of times does not reach the default value, it repeats step (A).

3. The capacitance testing method according to claim 1, Characterized in that: In step (A), when the variable error controller determines that the test time ends, it causes the capacitance testing device to display the error value.

4. The capacitance testing method according to claim 1, Characterized in that: 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 capacitance under test and / or the current value flowing through the capacitance under test.

5. The capacitance testing method according to claim 1, Characterized in that: The error value is N% of the target value, and each time the variable error controller increases the error value, it 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.

6. A capacitance testing device for testing a capacitance under test, It is characterized in that: The capacitance testing device includes: A transformer, whose secondary side is electrically connected to the capacitance to be tested; An AC signal generator, which is electrically connected to the 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 capacitance to be tested; A variable error controller, which is electrically connected to the AC signal generator; and A measuring instrument, which is electrically connected to the variable error controller and electrically connected to the capacitance to be tested to measure a measured value related to the capacitance to be tested; and the variable error controller performs the following steps: 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 determines that the measured value is less than a lower limit value, it proceeds to step (B), or when it determines that the measured value is greater than an upper limit value, it 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 commands the AC signal generator to increase the input power of the AC signal and accumulates an increase times, and when the variable error controller determines that the increase times reaches a default value, the variable error controller increases the error value and resets the increase times to zero, and then repeats step (A); and Step (C): The variable error controller commands the AC signal generator to decrease the input power of the AC signal and accumulates a decrease times, and when the variable error controller determines that the decrease times reaches the default value, the variable error controller increases the error value and resets the decrease times to zero, and then repeats step (A).

7. The capacitance testing device according to claim 6, It is characterized in that: In step (A), when the variable error controller determines that the measured value falls within the allowable range, it commands the AC signal generator to maintain the input power of the AC signal and repeats step (A); in step (B), when the variable error controller determines that the increase times does not reach the default value, it repeats step (A); in step (C), when the variable error controller determines that the decrease times does not reach the default value, it repeats step (A).

8. The capacitance testing device according to claim 6, It is characterized in that: In step (A), when the variable error controller determines that the test time ends, it commands the capacitance testing device to display the error value.

9. The capacitance testing device according to claim 6, It is characterized in that: 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 capacitance to be tested and / or the current value flowing through the capacitance to be tested.

10. The capacitance testing device according to claim 6, It is characterized in that: The error value is N% of the target value, and each time the variable error controller increases the error value, it makes the error value increase 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 of increasing the error value.

11. A computer-readable recording medium storing a software program which, when loaded and executed by a capacitance testing device, enables the capacitance testing device to perform the capacitance testing method according to any one of claims 1 to 5.

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