Withstand voltage testing device

Abstract

The invention discloses a withstand voltage testing device. The withstand voltage testing device comprises a current source, a switch module, a voltage measuring module and a control module, the current source is configured to output a test current. The switch module is configured to be connected between the current source and the coil element. The switch module switches on a first period in response to the control signal so as to supply a test current to the coil element in the first period. After the first period is finished, the switch module is closed to stop the supply of the test current to the coil element, so that the coil element generates back electromotive force. The voltage measuring module is configured to be connected with the coil element and measure the back electromotive force to obtain a measured voltage value. The control module is configured to be connected with the switch module and the voltage measurement module, generate a control signal, receive the measured voltage value and generate a withstand voltage test result according to the measured voltage value.

Description

Technical Field

[0001] The present invention relates to a withstand voltage test device, in particular to a device capable of setting a withstand voltage test environment and measuring the back electromotive force of a coil element to determine the withstand voltage test result. Background Art

[0002] Generally speaking, if coil components (such as inductors) in electronic products with coil components degrade, they can affect the stability and lifespan of the electronic product. Therefore, coil components must undergo a withstand voltage test to detect degradation. Current withstand voltage test circuits cannot control the current input to the coil components during withstand voltage testing. This results in the circuit measuring a voltage that is too high or too low when the test circuit's switch module is closed, making it impossible to accurately determine whether the coil components have degraded. Summary of the Invention

[0003] In view of this, in some embodiments, a withstand voltage test device is provided. The withstand voltage test device includes a current source, a switch module, a voltage measurement module and a control module. The current source is configured to output a test current. The switch module is configured to be connected between the current source and the coil element. The switch module is turned on for a first period in response to a control signal to supply a test current to the coil element during the first period. After the first period ends, the switch module is turned off to stop the supply of the test current to the coil element, so that the coil element generates a back electromotive force. The voltage measurement module is configured to connect the coil element and measure the back electromotive force to obtain a measured voltage value. The control module is configured to connect the switch module and the voltage measurement module, generate a control signal and receive a measured voltage value, and generate a withstand voltage test result based on the measured voltage value.

[0004] In some embodiments, the control module intermittently generates a plurality of control signals during the second period to obtain a plurality of measured voltage values ​​accordingly, and generates a withstand voltage test result according to the measured voltage values.

[0005] In some embodiments, the measured voltage value is a voltage peak value in a voltage bounce waveform caused by the back electromotive force.

[0006] In some embodiments, the control module obtains a voltage difference according to a voltage peak value, and compares the voltage difference with a judgment condition to generate a withstand voltage test result.

[0007] In some embodiments, the current value of the test current output by the current source during each first period within the second period is substantially the same.

[0008] In some embodiments, the control module performs the test during a third period, where the third period includes a plurality of second periods.

[0009] In some embodiments, the current source gradually increases the current value of the test current with each second period as a stage.

[0010] In some embodiments, the current value of the test current output by the current source during each first period within the second period is substantially the same.

[0011] In some embodiments, the control module obtains a voltage difference according to a voltage peak value, and compares the voltage difference with a judgment condition to generate a withstand voltage test result.

[0012] In some embodiments, the control module intermittently generates a plurality of control signals at the same time intervals during the second period.

[0013] In summary, in some embodiments, a withstand voltage test device is provided. The withstand voltage test device includes a current source, a switch module, a voltage measurement module and a control module. The control module can set the test environment for the withstand voltage test, for example, controlling the current source to output a test current of a specified current value during the second period, or gradually increasing the test current of each second period during the third period. This allows the control module to measure the back electromotive force fed back by the coil element under a variety of test environments according to product testing requirements, and to determine whether the coil element has degraded based on the back electromotive force. In this way, the withstand voltage test device can ensure that the back electromotive force measured under the test environment is stable, and thus accurately determine whether the coil element has degraded.

[0014] Various embodiments are described below in detail. However, these embodiments are intended for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, some components are omitted from the drawings in the embodiments to clearly illustrate the technical features of the present invention. The same reference numerals will be used throughout the drawings to indicate identical or similar components. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A block diagram of a withstand voltage testing device in some embodiments of the present invention;

[0016] Figure 2 A circuit diagram of a withstand voltage test device in some embodiments of the present invention;

[0017] Figure 3 In some embodiments of the present invention, a voltage waveform diagram caused by detecting the back electromotive force of the coil element is provided;

[0018] Figure 4 In some embodiments of the present invention, a voltage bounce waveform caused by back electromotive force is detected during the third period;

[0019] Wherein, the reference numerals:

[0020] 10: Withstand voltage test device;

[0021] 102: current source;

[0022] 104: switch module;

[0023] 1041: first end;

[0024] 1042: second end;

[0025] 1043: control terminal;

[0026] 106: voltage measurement module;

[0027] 108: control module;

[0028] 110: coil element;

[0029] 112: peak detection circuit;

[0030] I: test current;

[0031] P1: output path;

[0032] S1: current source switching signal;

[0033] S2: current source adjustment signal;

[0034] S3: control signal;

[0035] T1: first period;

[0036] T2, T21, T22, T23: second period;

[0037] T3: the third period;

[0038] Vp, Vp1, Vp2, Vp3, Vp4: voltage peak;

[0039] W, W1, W2, W3, W4: Voltage bounce waveform. DETAILED DESCRIPTION

[0040] See also Figure 1 、 Figure 2 and Figure 3 . Figure 1 FIG. 1 is a block diagram of a withstand voltage testing device 10 in some embodiments of the present invention. Figure 2 FIG. 1 is a circuit diagram of a withstand voltage testing device 10 in some embodiments of the present invention. Figure 3 In some embodiments of the present invention, the voltage waveform caused by the back electromotive force of the coil element 110 is detected. Figure 1 、 Figure 2 and Figure 3As shown, the withstand voltage test device 10 includes a current source 102, a switch module 104, a voltage measurement module 106 and a control module 108. The withstand voltage test device 10 is used to provide a test environment for performing a withstand voltage test on a coil element 110. In some embodiments, the test environment is determined by parameters such as a test current I output by the current source 102 and / or the time point of the action of the switch module 104 (to be explained later). The coil element 110 is, for example, a motor, an inductor, a transformer, a generator or other components with a coil. The withstand voltage test performed on the coil element 110 by the withstand voltage test device 10 refers to confirming the degree of degradation of the coil element 110 after being subjected to voltage based on the electrical information fed back by the coil element 110 after the withstand voltage test device 10 sets the test environment (degradation may refer to a decrease in the inductance value of the coil element 110).

[0041] The current source 102 is configured to output a test current I. The current source 102 can adjust the current value of the test current I outputted by it according to demand. In some embodiments, after receiving a setting signal, the current source 102 outputs a test current I of a specified current value corresponding to the setting signal, so that the current source 102 can output a test current I of a specified current value required in response to the needs of different test environments. The setting signal can be generated and sent through the control module 108, so that the control module 108 generates a corresponding setting signal according to the default working current of the coil element 110 or the test environment requirements to control the current source 102 to output a test current I of a specified current value. The current value of the test current I outputted by the current source 102 can be obtained according to a test voltage of the coil element 110. For example, before the withstand voltage test device 10 performs a withstand voltage test, the withstand voltage test device 10 can obtain the current value of the test current I through sampling after the withstand voltage test device 10 sets the test voltage of the coil element 110 according to the user. As Figure 2 As shown in FIG, the setting signal includes a current source switching signal S1 and a current source adjustment signal S2. Current source 102 outputs a test current I in response to current source switching signal S1. Current source 102 adjusts the current value of test current I in response to current source adjustment signal S2. In some embodiments, current source switching signal S1 includes a current start signal and a current end signal. Current source 102 outputs test current I in response to the current start signal. Current source 102 stops outputting test current I in response to the current end signal.

[0042] The switch module 104 is configured to be connected between the current source 102 and the coil element 110. In response to a control signal S3, the switch module 104 turns on for a first period T1, supplying a test current I to the coil element 110 during the first period T1. After the first period T1 ends, the switch module 104 turns off, ceasing the supply of the test current I to the coil element 110, causing the coil element 110 to generate a back electromotive force. In some embodiments, the switch module 104 may be a semiconductor switch element, such as a metal-oxide semiconductor field-effect transistor (MOSFET), a bipolar transistor, or an insulated-gate bipolar transistor (IGBT). In some embodiments, a starting point of the first period T1 is the time when the switch module 104 turns on, and an ending point of the first period T1 is the time when the current source 102 charges the coil element 110 to a specified current value (which may be the time when the coil element 110 is charged to the current value of the test current I). In some embodiments, the switch module 104 has a first terminal 1041, a second terminal 1042, and a control terminal 1043. The first terminal 1041 is coupled to the current source 102, the second terminal 1042 is coupled to the coil element 110, and the control terminal 1043 is configured to receive a control signal S3 to conduct the first terminal 1041 and the second terminal 1042, thereby forming an output path P1, allowing the test current I to be input to the coil element 110 via the output path P1. In some embodiments, when the switch module 104 is turned off in response to the control signal S3, the current source 102 stops outputting the test current I in response to the current signal.

[0043] In some embodiments, the first period T1 is the time during which the switch module 104 turns on the output path P1 after receiving the control signal S3 . Accordingly, the test current I can pass through the switch module 104 and be input to the input coil element 110 during the first period T1 .

[0044] The voltage measurement module 106 is configured to connect to the coil element 110 and measure the terminal voltage of the coil element 110 to measure the back electromotive force generated by the coil element 110 in response to the disappearance of the test current I, thereby obtaining a measured voltage value. The control module 108 obtains the measured voltage value from the voltage measurement module 106. In some embodiments, the measured voltage value is a voltage peak value Vp in a voltage bounce waveform W caused by the back electromotive force. Figure 3As shown, since the voltage bounce waveform W is caused by back electromotive force, the voltage peak Vp is the maximum negative amplitude in the voltage bounce waveform W. It should be noted that each time the switch module 104 completes a test cycle (including maintaining the on-state during the first period T1 and the subsequent off-state), the voltage measurement module 106 can measure the voltage bounce waveform W. Furthermore, the voltage bounce waveform W is a high-frequency signal. Capturing the complete waveform generally requires a voltage measurement device with high-speed voltage measurement capabilities, which is expensive. Therefore, the voltage measurement module 106 may not have high-speed voltage measurement capabilities to save costs. The voltage measurement capability of the voltage measurement module 106 only needs to be sufficient to capture the voltage peak Vp in the voltage bounce waveform W, allowing the control module 108 to determine the degree of deterioration of the coil element 110 based on the voltage peak Vp. It should be noted that the voltage measurement module 106 is not limited to having high-speed voltage measurement capabilities. In other words, even if it has high-speed voltage measurement capabilities, it can still capture the voltage peak value Vp and provide it to the control module 108 for determining the degree of degradation of the coil element 110. In some embodiments, the voltage measurement module 106 includes a peak detection circuit 112. The peak detection circuit 112 is used to capture and record a voltage peak value Vp in the voltage bounce waveform W, allowing the control module 108 to determine the degree of degradation of the coil element 110 based on the voltage peak value Vp.

[0045] The control module 108 is configured to connect to the switch module 104 and the voltage measurement module 106. The control module 108 generates a control signal S3 and receives a measured voltage value. The control module 108 generates a withstand voltage test result based on the measured voltage value. In some embodiments, the withstand voltage test result is a pass result or a fail result (described later). If the withstand voltage test result is a pass result, it indicates that the coil element 110 is a good product (the degree of degradation is within the tolerance range). If the withstand voltage test result is a fail result, it indicates that the coil element 110 is a defective product (the degree of degradation exceeds the tolerance range).

[0046] For example Figure 3 As shown, in some embodiments, the control module 108 intermittently generates multiple control signals S3 during a second period T2 to obtain multiple measured voltage values, and generates a withstand voltage test result based on these measured voltage values. Specifically, during the second period T2, the switch module 104 responds to the received multiple control signals S3 and turns on the output path P1 multiple times during the first period T1. For example Figure 3 As shown in FIG, four voltage bounce waveforms (W1 to W4) corresponding to four test cycles occurred in the second period T2. Figure 3For the sake of convenience, only four waveforms are shown, and some embodiments of the present invention are not limited to this number. In some embodiments, there are 512 test cycles in the second period T2.

[0047] For example Figure 3 As shown, in some embodiments, the current source 102 outputs substantially the same current value of the test current I during each first period T1 within the second period T2. That is, each test cycle provides the same first period T1 and test current I (i.e., the test environment is the same). Consequently, the control module 108 receives multiple measured voltage values ​​corresponding to each of these test cycles with the same test environment and uses these measured voltage values ​​to determine the withstand voltage test results.

[0048] For example Figure 3 As shown, in some embodiments, the control module 108 obtains a first voltage difference based on the voltage peak value Vp and a voltage setting value, and compares the first voltage difference with a judgment condition to generate a withstand voltage test result. The judgment condition can be to determine whether the voltage difference falls within a threshold value to determine the withstand voltage test result. It should be noted that the first voltage difference is the difference between each voltage peak value (Vp1, Vp2, Vp3, Vp4) during the second period T2 and the voltage setting value. In some embodiments, the control module 108 obtains a second voltage difference by subtracting the maximum voltage peak value Vp detected during the second period T2 from at least one voltage peak value Vp detected thereafter (such as any one or more voltage peak values ​​or each subsequent voltage peak value), and compares the second voltage difference with the threshold value to generate the withstand voltage test result. The aforementioned "determining whether the voltage difference falls within the threshold value to determine the withstand voltage test result" can mean that the voltage difference is substantially equal to the threshold value, or it can mean that the voltage difference falls within the threshold range (the range between an upper limit and a lower limit of one of the threshold values).

[0049] The following description uses the withstand voltage test apparatus 10 to set the test environment to output substantially the same current value during the same second period T2, and the control module 108 to determine whether the coil element 110 is degraded based on the measured back electromotive force.

[0050] exist Figure 3In one embodiment, the upper limit of the threshold is 0.5V and the lower limit is -0.5V. For example, when the difference between each voltage peak value (Vp1, Vp2, Vp3, Vp4) and the voltage setting value during the second period T2 is 0V (i.e., the first voltage difference is 0), the control module 108 compares the first voltage difference to fall within the threshold range and accordingly determines that the withstand voltage test result is a pass. For another example, when the difference between any voltage peak value (Vp1, Vp2, Vp3, Vp4) and the voltage setting value during the second period T2 is 1V (i.e., the first voltage difference is 1), the control module 108 compares the first voltage difference to fall outside the threshold range and accordingly determines that the withstand voltage test result is a fail.

[0051] exist Figure 3 In another embodiment, the upper limit of the threshold is 0.5V and the lower limit is -0.5V. When the difference between the maximum voltage peak value Vp1 detected during the second period T2 and any subsequent voltage peak value Vp2 is 0V (i.e., the second voltage difference is 0), the control module 108 compares the second voltage difference to find that it falls within the threshold range and, accordingly, determines that the withstand voltage test result is a pass. For another example, when the difference between the maximum voltage peak value Vp1 detected during the second period T2 and any subsequent voltage peak value (Vp2, Vp3, Vp4) is 1V (i.e., the second voltage difference is 1), the control module 108 compares the second voltage difference to find that it exceeds the threshold range and, accordingly, determines that the withstand voltage test result is a fail.

[0052] Please also refer to Figure 2 and Figure 4 . Figure 4 In some embodiments of the present invention, the voltage bounce waveform caused by the back electromotive force is detected during the third period T3. Figure 2 and Figure 4 As shown, in some embodiments, the control module 108 performs a withstand voltage test (eg, breakdown voltage analysis) during a third period T3. Figure 4 As shown in FIG, the third period T3 includes multiple second periods ( T21 , T22 , T23 ), and the control module 108 can complete multiple withstand voltage tests within the third period T3 (each second period T2 ends, indicating that one withstand voltage test is completed).

[0053] In some embodiments, the current source 102 can use each second period (T21, T22, T23) as a stage and gradually increase the current value of the test current I. For example, the current source 102 outputs a test current I of a first current value during the second period T21 and increases the current value of the next output at the end of the first period T1. Therefore, the current source 102 can output a test current I of a second current value (the second current value is greater than the first current value) during the second period T22. In this way, the withstand voltage test device 10 can set the test environment to gradually increase the current value during the third period T3, allowing the control module 108 to measure a maximum withstand voltage value of the coil element 110 (the measured voltage value immediately before the measured voltage value is increased or decreased is used as the maximum withstand voltage value). In some embodiments, the current source 102 gradually increases the current value according to the same ratio (5% to 20%).

[0054] For example Figure 4 As shown, in some embodiments, the current value of the test current I output by the current source 102 during each first period T1 within the second period T2 is substantially the same. For example, the test current I output by the current source 102 during a first period T1 and another first period T1 during the second period T21 is substantially the same (within an allowable range error in measurement). Thus, the withstand voltage test apparatus 10 can configure the test environment to output the test current I of substantially the same current value within the same second period T2 (i.e., between withstand voltage tests), allowing the control module 108 to detect whether the measured voltage value of the coil element 110 has increased or decreased.

[0055] The following description uses the withstand voltage test apparatus 10 to set the test environment to gradually increase the current value of the second period T2 during the third period T3, and the control module 108 to determine whether the coil element 110 is degraded based on the measured back electromotive force.

[0056] exist Figure 4In one embodiment, the control module 108 subtracts the maximum voltage peak Vp1 measured during the second period T2 from at least one subsequent voltage peak (Vp2, Vp3, Vp4) (e.g., any one or more voltage peaks or each subsequent voltage peak) to obtain one or more third voltage differences (the third voltage difference being voltage peak Vp2 minus voltage peak Vp1, voltage peak Vp3 minus voltage peak Vp1, or voltage peak Vp4 minus voltage peak Vp1). The control module 108 determines a test pass result based on whether each third voltage difference falls within a threshold. For example, during the second period T21, voltage peak Vp1 is measured to have a maximum voltage of 5.5V. Subsequently, voltage peak Vp2 is measured to be 5.2V, voltage peak Vp3 is measured to be 5.4V, voltage peak Vp3 is measured to be 5.5V, and voltage peak Vp4 is measured to be 5.4V. The control module 108 subtracts the voltage peak Vp1 from any subsequently detected voltage peak (Vp2, Vp3, Vp4) to obtain third voltage differences of -0.3V, -0.1V, 0V, and -0.1V, respectively. When the threshold is -0.5V, the control module 108 compares each of the third voltage differences to see if they fall within the threshold range and, accordingly, determines that the withstand voltage test result has passed. For another example, if the measured voltage peak Vp1 has a maximum voltage of 5.5V, and then the voltage peaks Vp2, Vp3, and Vp4 are detected as 4.5V, 4.5V, and 4.7V, respectively, the control module 108 subtracts the voltage peaks Vp1 from the voltage peaks Vp2 to obtain a third voltage difference of -1V (4.5V-5.5V). The control module 108 compares each of the third voltage differences to see if they fall within the threshold range and, accordingly, determines that the withstand voltage test result has failed.

[0057] exist Figure 4In another embodiment, the control module 108 subtracts the voltage peak values ​​Vp of two consecutive second periods (such as T21 and T22, or T22 and T23, etc.) to obtain a fourth voltage difference. The control module 108 determines whether the test is passed based on whether the fourth voltage difference falls within a threshold. For example, the upper limit of the threshold is 0.5V and the lower limit is -0.5V. The voltage measurement module 106 measures a voltage peak value Vp1 of 5V during the second period T21 and a voltage peak value Vp2 of 5.2V during the second period T22. The control module 108 subtracts the two voltage peak values ​​(Vp1, Vp2) to obtain a fourth voltage difference of 0.2V, and compares the fourth voltage difference (0.2V) to see if it falls within the threshold (0.5V to -0.5V), thereby determining that the withstand voltage test result is a passed result. For another example, the voltage measurement module 106 measures a voltage peak value Vp1 of 5V during the second period T21 and a voltage peak value Vp2 of 5.6V during the second period T22. The control module 108 subtracts the two voltage peak values ​​(Vp1, Vp2) to obtain a fourth voltage difference of 0.6V. The control module 108 determines that the fourth voltage difference (0.6V) exceeds the threshold value (0.5V to -0.5V) and determines that the withstand voltage test result is a failure. It should be noted that in this embodiment, the control module 108 obtains the fourth voltage difference by subtracting any voltage peak value (Vp1, Vp2, Vp3, Vp4) during the second period T21 from any voltage peak value (Vp1, Vp2, Vp3, Vp4) during the second period T22 (this can also be done by subtracting the second period T22 from the second period T23). In other embodiments, the control module 108 obtains the fourth voltage difference by subtracting the average value of all voltage peak values ​​(Vp1, Vp2, Vp3, Vp4) in the second period T21 from the average value of all voltage peak values ​​(Vp1, Vp2, Vp3, Vp4) in the second period T22 (it may also be the subtraction of the subsequent second period T22 from the second period T23).

[0058] exist Figure 4In another embodiment, the control module 108 subtracts two consecutive voltage peaks Vp measured during two adjacent test cycles during the same second period T2 to obtain a fifth voltage difference. The control module 108 determines a test pass result based on whether the fifth voltage difference falls within a threshold. For example, the threshold has an upper limit of 0.5V and a lower limit of -0V. The voltage measurement module 106 measures a first voltage peak Vp1 of 5V and a second voltage peak Vp2 of 5V during the second period T21. The control module 108 subtracts the measured voltage values ​​of the two consecutive voltage peaks (Vp1, Vp2) to obtain a fifth voltage difference of 0V. The control module 108 then checks whether the fifth voltage difference (0V) falls within the threshold range (0.5V to 0V). (If the voltage peaks do not show a significant downward trend or do not show any downward trend during the second period T21, it indicates that the coil element 110 has not degraded.) The control module 108 then determines the withstand voltage test result as a pass. For example, the voltage measurement module 106 measures a first voltage peak Vp1 of 5V and a second voltage peak Vp2 of 4.4V during the second period T21. The control module 108 subtracts the measured voltage values ​​of the two consecutive voltage peaks (Vp1, Vp2) to obtain a fifth voltage difference of 0.6V. The control module 108 compares the fifth voltage difference (0.6V) to determine whether it exceeds a threshold value (0.5V to 0V). Based on this, the control module 108 determines that the withstand voltage test result is a failure (the voltage peaks show a significant downward trend during the second period T21, indicating functional degradation of the coil element 110).

[0059] exist Figure 4 In another embodiment, the control module 108 determines the test pass result based on whether an inductance change falls within a threshold value. The control module 108 can apply the measured voltage value to the formula (1) described later to obtain the corresponding inductance change. The control module 108 obtains an inductance change based on the voltage peak value Vp of two adjacent second periods T2. For example, the upper limit value of the threshold is 5% and the lower limit value is -5%. The voltage measurement module 106 measures the measured voltage value of the voltage peak value Vp1 as 5V in the first second period T21 and the measured voltage value of the voltage peak value Vp1 as 5V in the second second period T22. The control module 108 obtains an inductance change of 0% based on the two voltage peak values ​​Vp1. The control module 108 can obtain the inductance change according to the following formula (1):

[0060]

[0061] Vs 2 The voltage peak value Vp1 measured during the first second period T21; Vx 2It is the voltage peak value Vp2 measured in the second period T22 after the second period T21 (it can also be the voltage peak value in the second period T23 or its subsequent period).

[0062] The control module 108 compares the inductance change of 0% to fall within the threshold value (0% to 5%) (indicating that the inductance characteristics of the coil element 110 are normal), and accordingly determines that the withstand voltage test result is a passed result. For another example, the voltage measurement module 106 measures the voltage value of the voltage peak Vp1 as 5V in the first second period T21 of the third period T3, and the voltage value of the voltage peak Vp2 as 5.2V in the second second period T22. The control module 108 obtains the inductance change of 8.16% (Vs 2 5.2V, Vx 2 =5V, the inductance change calculated according to formula (1) is 8.16%. The control module 108 compares the inductance change (8.16%) to see if it exceeds the threshold value (5% to -5%) (the measured voltage value rises, indicating that the inductance of the coil element 110 has decreased), and accordingly determines that the withstand voltage test result is a failure. It should be noted that in this embodiment, the control module 108 uses any voltage peak (Vp1, Vp2, Vp3, Vp4) in the first second period T21 and any voltage peak (Vp1, Vp2, Vp3, Vp4) in any subsequent second period (T22, T23) as parameters of the aforementioned formula (1) to obtain the inductance change. In other embodiments, the control module 108 uses the average value of all voltage peak values ​​(Vp1, Vp2, Vp3, Vp4) in the first second period T21 and the average value of all voltage peak values ​​(Vp1, Vp2, Vp3, Vp4) in any subsequent second period (T22, T23) as parameters of the aforementioned formula (1) to obtain the inductance change.

[0063] exist Figure 4In another embodiment, the control module 108 subtracts the calculated inductance changes during the two consecutive second periods T2 to obtain an inductance change difference. The control module 108 determines whether the test passes based on whether the inductance change difference falls within a threshold. For example, the control module 108 determines an inductance change of 0% based on two consecutive voltage peaks Vp1 during the first set (second periods T21 and T22), and another determines an inductance change of 0% based on two consecutive voltage peaks Vp1 during the second set (second periods T22 and T23). The two sets of inductance changes are subtracted to obtain an inductance change difference of 0%. The control module 108 determines that the inductance change difference (0%) does not exceed a threshold (5% to -5%) (the increase in the measured voltage value is within an acceptable range, indicating that the inductance of the coil component 110 is normal), and thus determines that the withstand voltage test result passes. For another example, the control module 108 obtains an inductance change of 0% based on the two voltage peaks Vp1 during the first set (second period T21 and second period T22), and obtains an inductance change of 6% based on the two voltage peaks Vp1 during the second set (second period T22 and second period T23). The two sets of inductance changes are subtracted to obtain a difference in inductance change of -6%. The control module 108 compares the inductance change difference (-6%) and determines whether it falls within a threshold range (5% to -5%) (the increase in the measured voltage exceeds the acceptable range, indicating that the inductance of the coil element 110 has decreased), and accordingly determines that the withstand voltage test result has failed.

[0064] In some embodiments, the control module 108 selectively uses any one or more of the aforementioned determination methods to determine the degree of degradation of the coil element 110. For example, the control module 108 determines an inductance change of 10% based on the two voltage peaks Vp1 of the first group (second period T21 and second period T22), and also determines an inductance change of 10% based on the two voltage peaks Vp1 of the second group (second period T22 and second period T23). The two sets of inductance changes are subtracted to obtain an inductance change difference of 0%. Although the inductance change difference is 0%, the control module 108 compares the inductance changes of the first and second groups (10%) and finds that they are within a threshold range (5% to -5%) (the increase in the measured voltage value exceeds the acceptable range, indicating that the inductance value of the coil element 110 has decreased). Therefore, the control module 108 determines that the withstand voltage test result still fails.

[0065] For example Figure 3 and Figure 4As shown, in some embodiments, the control module 108 intermittently generates multiple control signals S3 at the same time interval during the second period T2. For example, the voltage bounce waveform W1 and the voltage bounce waveform W2 form a first time interval, while the voltage bounce waveform W2 and the voltage bounce waveform W3 form a second time interval, with the first time interval being substantially equal to the second time interval. This ensures that the interval between the switch being turned on again and the next time the switch is turned on remains consistent, ensuring that each voltage bounce waveform W2 detected during the second period T2 is generated under the same test environment.

[0066] In summary, in some embodiments, a withstand voltage test device 10 is provided. The withstand voltage test device 10 includes a current source 102, a switch module 104, a voltage measurement module 106, and a control module 108. The control module 108 can set the test environment for the withstand voltage test, for example, controlling the current source 102 to output a test current I of a specified current value during the second period T2, or gradually increasing the test current I of each second period T2 during the third period T3. This allows the control module 108 to measure the back electromotive force fed back by the coil element 110 under a variety of test environments according to product testing requirements, and to determine whether the coil element 110 has degraded based on the back electromotive force. In this way, the withstand voltage test device 10 can ensure that the back electromotive force measured under the test environment is stable, and thus accurately determine whether the coil element 110 has degraded.

[0067] The embodiments described above are merely illustrative of the technical concepts and features of this application. Their purpose is to enable those familiar with the art to understand the content of this application and implement it accordingly. They should not be used to limit the scope of the patent application of this application. In other words, any equivalent changes or modifications made based on the spirit disclosed in this application should still be included in the scope of the patent application of this application.

Claims

1. A withstand voltage test device, suitable for testing a coil component, characterized in that: The withstand voltage test device includes: a current source configured to output a test current; a switch module configured to be connected between the current source and the coil element, the switch module being turned on for a first period in response to a control signal to supply the test current to the coil element during the first period, and being turned off after the first period to stop supplying the test current to the coil element, so that the coil element generates a back electromotive force; a voltage measurement module configured to be connected to the coil element and measure the back electromotive force to obtain a measured voltage value; and A control module is configured to connect the switch module and the voltage measurement module, generate the control signal and receive the measured voltage value, and generate a withstand voltage test result according to the measured voltage value.

2. The withstand voltage test device according to claim 1, characterized in that: The control module intermittently generates a plurality of the control signals in a second period to obtain a plurality of the measured voltage values ​​accordingly, and generates the withstand voltage test result according to the measured voltage values.

3. The withstand voltage test device according to claim 2, characterized in that: The measured voltage value is a voltage peak value in a voltage bounce waveform caused by the back electromotive force.

4. The withstand voltage test device according to claim 3, characterized in that: The control module obtains a voltage difference according to the voltage peak value, and compares the voltage difference with a judgment condition to generate the withstand voltage test result.

5. The withstand voltage test device according to claim 2, characterized in that: The current source outputs the same current value of the test current during each of the first periods within the second period.

6. The withstand voltage test device according to claim 2, characterized in that: The control module performs a test in a third period, and the third period includes a plurality of the second periods.

7. The withstand voltage test device according to claim 6, characterized in that: The current source gradually increases a current value of the test current with each second period as a stage.

8. The withstand voltage test device according to claim 7, characterized in that: The current value of the test current output by the current source during each of the first periods within the second period is the same.

9. The withstand voltage test device according to claim 8, characterized in that: The control module obtains a voltage difference according to a voltage peak value, and compares the voltage difference with a judgment condition to generate the withstand voltage test result.

10. The withstand voltage test device according to claim 2 or 9, characterized in that: The control module intermittently generates a plurality of the control signals at the same time interval during the second period.

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