Surge testing device for power devices
By automatically controlling the conduction and cutoff of the target switch and the power device under test through a half-wave rectifier circuit and controller, the problem of low efficiency in traditional surge current testing is solved, and efficient automated testing of multiple surge current tests is realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA ELECTRONICS RELIABILITY AND ENVIRONMENTAL TESTING INSTITUTE ((THE FIFTH INSTITUTE OF ELECTRONICS MINISTRY OF INDUSTRY AND INFORMATION TECHNOLOGY) (CHINA SAIBAO LABORATORY)
- Filing Date
- 2022-07-13
- Publication Date
- 2026-08-04
AI Technical Summary
Traditional surge current testing of power devices requires manual control of double-throw switches, resulting in low testing efficiency and difficulty in conducting multiple surge current tests.
A half-wave rectifier circuit and controller are used to automatically control the conduction and cutoff of the target switch and the power device under test, and multiple surge tests are achieved through the half-wave rectified signal.
It improves the efficiency of surge testing, enabling multiple surge current tests to be performed automatically, reducing manual operation and saving time and manpower.
Smart Images
Figure CN115144720B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of semiconductor device reliability testing technology, and in particular to a surge testing device for power devices. Background Technology
[0002] With the continuous upgrading of power device performance, they are widely used in power, transportation, and home appliances. However, in industrial applications, unexpected voltage transients and inrush currents often degrade the performance of electronic equipment, leading to failures or even damage. Therefore, protection against voltage transients and inrush currents has become a crucial component in improving the reliability of electronic equipment. In practical applications, power devices may experience brief periods of high current density due to instantaneous high current pulses exceeding their rated current values, such as lightning strikes, poor grounding, and the switching on and off of large power loads. This necessitates that power devices possess a certain high current withstand capability, enabling them to continue operating normally after experiencing inrush currents.
[0003] In traditional technologies, the surge current withstand capability of power devices is studied by conducting surge current tests to simulate the actual operating environment of the power devices. Existing surge current tests require manual control of a double-throw switch to perform the test.
[0004] However, since only a single surge current test can be performed by manually controlling the double-throw switch to close once, multiple surge current tests require manually controlling the double-throw switch to close multiple times, which is time-consuming, labor-intensive, and inefficient. Summary of the Invention
[0005] Therefore, it is necessary to provide a surge testing device for power devices that can improve surge testing efficiency in response to the above-mentioned technical problems.
[0006] This application provides a surge testing device for power devices. The device includes a half-wave rectifier circuit, a controller, a power device under test, a target switch, and a computer device;
[0007] The controller is configured to receive test commands sent by the computer device and send control commands to the half-wave rectifier circuit according to the test commands.
[0008] The half-wave rectifier circuit is used to acquire a half-wave rectified signal according to the control command, wherein the half-wave rectified signal includes a preset number of sinusoidal half-waves.
[0009] The controller is also configured to close the target switch and turn on the power device under test when it detects that the half-wave rectified signal starts to rise from the first preset voltage, so as to obtain surge test results when current passes between the drain and source electrodes of the power device under test.
[0010] In one embodiment, the first terminal of the target switch is connected to the first terminal of the half-wave rectifier circuit, the second terminal of the target switch is connected to the drain of the power device under test, and the third terminal of the target switch is connected to the controller.
[0011] In one embodiment, the gate of the power device under test is connected to the controller, and the source of the power device under test is grounded.
[0012] In one embodiment, the device further includes a current probe, a first end of which is grounded, a second end of which is connected to the source of the power device under test, and a third end of which is connected to the computer equipment.
[0013] In one embodiment, the device further includes a voltage probe, a first end of which is connected to the drain of the power device under test, a second end of which is connected to the source of the power device under test, and a third end of which is connected to the computer equipment.
[0014] In one embodiment, the device further includes an oscilloscope, with the third end of the current probe connected to the computer device via the oscilloscope, and the third end of the voltage probe connected to the computer device via the oscilloscope.
[0015] In one embodiment, the controller includes a detection circuit and a processing circuit, the detection circuit being connected to the processing circuit;
[0016] The detection circuit is used to detect the half-wave rectified signal, obtain a detection result, and send the detection result to the processing circuit.
[0017] The processing circuit is used to control the target switch to close and control the power device under test to conduct when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage.
[0018] In one embodiment, the controller further includes a switch control circuit and a gate voltage generation circuit, both of which are connected to the processing circuit;
[0019] The switch control circuit is used to receive the detection result sent by the processing circuit, and control the target switch to close when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage;
[0020] The gate voltage generating circuit is used to receive the detection result sent by the processing circuit, and control the power device under test to turn on when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage.
[0021] In one embodiment, the controller further includes an interface circuit connected to the computer device and also connected to the processing circuit.
[0022] The interface circuit is used to receive test commands sent by the computer device and send the test commands to the processing circuit, so that the processing circuit can send control commands to the half-wave rectifier circuit according to the test commands.
[0023] In one embodiment, the half-wave rectifier circuit includes an AC power supply, a first transformer, a second transformer, and a half-wave rectifier module. The two ends of the first transformer are respectively connected to the AC power supply. The second transformer is connected in series with the first transformer and is connected to the half-wave rectifier module. The first end of the half-wave rectifier module is connected to the target switch, and the second end of the half-wave rectifier module is connected to the controller.
[0024] The surge testing device for the aforementioned power device includes a half-wave rectifier circuit, a controller, a power device under test (DUT), a target switch, and a computer. The controller receives test commands from the computer and sends control commands to the half-wave rectifier circuit according to the test commands. The half-wave rectifier circuit acquires a half-wave rectified signal according to the control commands, wherein the half-wave rectified signal includes a preset number of sinusoidal half-waves. The controller also controls the target switch to close and the DUT to conduct when it detects that the half-wave rectified signal is rising from a first preset voltage, so as to obtain surge test results when current passes between the drain and source electrodes of the DUT. In other words, in this embodiment, the controller receives test instructions sent by the computer device and sends control instructions to the half-wave rectifier circuit according to the test instructions. Then, the half-wave rectifier circuit obtains a half-wave rectified signal containing a preset number of sinusoidal half-waves according to the control instructions. When the controller detects that the half-wave rectified signal starts to rise from the first preset voltage, it controls the target switch to close and controls the power device under test to conduct, so as to obtain the surge test result when the current passes between the drain and source electrodes of the power device under test. Since the power device under test experiences a half-wave rectified signal containing a preset number of sinusoidal half-waves, the surge test can be automatically repeated on the power device under test to obtain a surge test result containing a preset number of half-waves. For example, the controller receives a test command sent by the computer device and sends a control command containing a preset number of sine half-waves to the half-wave rectifier circuit according to the test command. When the preset number is 5, the half-wave rectifier circuit obtains a half-wave rectified signal containing 5 sine half-waves according to the control command containing 5 sine half-waves. Then, when the controller detects that the half-wave rectified signal starts to rise from the first preset voltage, it controls the target switch to close and controls the power device under test to turn on. Since the half-wave rectified signal includes 5 sine half-waves, a total of 5 surge currents are formed, thereby obtaining a surge test result containing 5 surge tests, so as to improve the surge test efficiency. Attached Figure Description
[0025] Figure 1 This is a schematic diagram of a circuit used in the prior art for surge testing of power devices;
[0026] Figure 2 A schematic diagram of a surge testing device for a power device provided in an embodiment of this application;
[0027] Figure 3 A circuit diagram of a surge testing device for a power device provided in an embodiment of this application;
[0028] Figure 4 This application provides a schematic diagram of the internal structure of a controller according to an embodiment of the present application;
[0029] Figure 5A circuit diagram of a surge testing device for a power device provided in another embodiment of this application. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0031] Power devices are widely used in various sectors of the national economy, including power, transportation, communications, machinery, and household appliances. In industrial applications, unexpected voltage transients and inrush currents frequently degrade the performance of electronic equipment, leading to malfunctions or even damage. Therefore, protection against voltage transients and surges is a crucial component in improving the reliability of electronic equipment. In circuit systems, the surge current withstand capability of power devices is a fundamental requirement for their reliable operation in industrial applications. For example, in practical applications, during the startup of motor drives powered by power factor correction (PFC) or inverters, power devices must withstand currents several times their rated current. When power devices experience lightning strikes, large power load connections and disconnections, short circuits, or poor grounding, they may experience transient high current density states due to instantaneous high current pulses exceeding their rated current values. This necessitates that power devices possess a certain high current withstand capability, enabling them to continue operating normally after experiencing surge currents.
[0032] Surge current withstand capability studies of power devices involve conducting surge current tests to evaluate their stability under instantaneous high-current pulses, simulating their actual operating environment. Testing the surge current withstand capability of power devices provides important references for application and circuit design personnel, ensuring that power devices operate within safe operating ranges in practical applications, or suppressing transient currents exceeding the device's surge current withstand capability through circuit design. Furthermore, since surge currents can cause power device failure and damage, they expose the causes of failure under high current density operating conditions, providing feedback to device designers and manufacturers to improve component structure and enhance the reliability of power devices under high current density operating conditions.
[0033] Surge current testing involves exposing the power device to a dry, constant-temperature environment and applying a sinusoidal half-wave positive high-current pulse, causing instantaneous degradation or damage. This allows the evaluation of the power device's transient high-current withstand capability and is one of the most commonly used tests for evaluating power device reliability. Surge current testing includes single-surge pulse testing and repetitive surge pulse testing. The ability to withstand a single surge current impact characterizes the power device's limit of withstanding a single large current pulse, while the ability to withstand repetitive surge current pulses characterizes the degree of characteristic degradation after withstanding multiple large current pulses.
[0034] In traditional technology, surge current testing of power devices requires manual control of a double-throw switch. Each connection of the double-throw switch initiates one surge current test. Figure 1 , Figure 1 The circuit diagram for surge current testing of power devices in the prior art is shown below. The specific testing process is as follows:
[0035] At the start of each test, connect the double-throw switch in the circuit to point 1, which is the adjustable voltage source V. DD The DC source charges capacitor C, and then the double-throw switch is connected to point 2, so that capacitor C and inductor L form an LC resonant circuit, which can generate a sinusoidal test current pulse starting from zero point and act on the power device under test, causing the power device under test to experience a surge process; when the sinusoidal test current pulse starting from zero point crosses zero point again, the double-throw switch connected to point 2 is opened, the sinusoidal test current pulse starting from zero point disappears, which also means that the surge test is over. At the same time, the instrument records the voltage waveform and current waveform during the surge test.
[0036] However, in practical applications, power devices often experience repeated surge current impacts. Traditional surge current testing, which involves manually controlling a double-throw switch to close once, can only perform a single surge current test. To conduct multiple surge current tests, the double-throw switch needs to be manually closed multiple times, resulting in time-consuming and labor-intensive testing with low efficiency.
[0037] To address the aforementioned technical problems, embodiments of this application provide a surge testing device for power devices. (Refer to...) Figure 2 , Figure 2This is a schematic diagram of a surge testing device for a power device provided in an embodiment of this application. The device includes: a half-wave rectifier circuit 23, a controller 21, a power device under test 22, a target switch 24, and a computer device 20. The controller 21 is used to receive test commands sent by the computer device 20 and send control commands to the half-wave rectifier circuit 23 according to the test commands. The half-wave rectifier circuit 23 is used to acquire a half-wave rectified signal according to the control commands, wherein the half-wave rectified signal includes a preset number of sinusoidal half-waves. The controller 21 is also used to control the target switch 24 to close and control the power device under test 22 to conduct when the half-wave rectified signal is detected to rise from a first preset voltage, so as to obtain surge test results when current passes between the drain and source electrodes of the power device under test 22.
[0038] It should be noted that, in order to avoid overheating of the power device under test, when the preset number of surge tests exceeds 20, the power device under test 22 needs to undergo multiple rounds of surge current tests. For example, if the preset number of sine half-waves is n and the preset number of surge tests is b, then m (m = b / n) rounds of surge current tests are required to avoid overheating of the power device under test 22. The computer device 20 automatically limits the interval time of each round of surge current test according to n / m, that is, the surge current pulse interval time, to ensure that the working percentage of the power device under test 22 d ≦ 0.05.
[0039] To illustrate with the above example, taking a test instruction that includes one round of testing, which can perform 10 surge current tests as an example, the controller 21 receives a test instruction from the computer device 20 that includes 10 surge tests, and sends a control instruction containing 10 sine half-waves to the half-wave rectifier circuit 23 according to the test instruction, and obtains 10 sine half-wave rectified signals. When the controller 21 detects that the half-wave rectified signal starts to rise from the first preset voltage 0V, it controls the target switch 24 to close and controls the power device under test 22 to conduct, so that when the current passes between the drain and source electrodes of the power device under test 22, the surge test result containing 10 surge tests is obtained.
[0040] The above example illustrates a test command consisting of a single test round. Here, we take a test command consisting of multiple test rounds, where each round can perform 20 surge current tests. The controller 21 receives a test command from the computer device 20 containing 60 surge tests and, based on this command, sends a control command to the half-wave rectifier circuit 23 containing 20 sinusoidal half-waves to obtain the 20 sinusoidal half-wave rectified signals. When the controller 21 detects that the half-wave rectified signal is rising from the first preset voltage of 0V, it controls the target switch 24 to close and controls the power device under test 22 to conduct. This allows for the acquisition of surge test results containing 20 surge tests when current flows between the drain and source electrodes of the power device under test 22. Afterward, the controller 21 controls the target switch 24 to open and controls the gate-source voltage V of the power device under test 22. gs A voltage less than or equal to the threshold voltage causes the power device under test (DUT) 22 to turn off, signifying that DUT 22 has completed one round of surge current testing. After the interval between each round of surge current testing, when the controller 21 detects that the half-wave rectified signal is rising from the first preset voltage of 0V, it controls the target switch 24 to close and controls DUT 22 to turn on, so that the surge test result is obtained when current passes between the drain and source electrodes of DUT 22. After three rounds of surge current testing in the above manner, the controller 21 controls the target switch 24 to open and controls the gate-source voltage V of DUT 22. gs If the voltage is less than or equal to the threshold voltage, the power device under test 22 will be turned off.
[0041] It should be noted that: if the gate-source voltage V of the power device under test is 22... gs If the voltage is less than or equal to the threshold voltage, the power device under test 22 is turned off; if the gate-source voltage V of the power device under test 22 is less than or equal to the threshold voltage, the device is turned off. gs If the voltage exceeds the threshold voltage, the power device under test 22 will conduct.
[0042] The surge testing device for the aforementioned power device includes a half-wave rectifier circuit 23, a controller 21, a power device under test 22, a target switch 24, and a computer device 20. The controller 21 is used to receive test commands sent by the computer device 20 and send control commands to the half-wave rectifier circuit 23 according to the test commands. The half-wave rectifier circuit 23 is used to acquire a half-wave rectified signal according to the control commands, wherein the half-wave rectified signal includes a preset number of sinusoidal half-waves. The controller 21 is also used to control the target switch 24 to close and control the power device under test 22 to conduct when the half-wave rectified signal is detected to rise from a first preset voltage, so as to obtain surge test results when current passes between the drain and source electrodes of the power device under test 22. In other words, in this embodiment, the controller 21 receives the test command sent by the computer device 20 and sends a control command to the half-wave rectifier circuit 23 according to the test command. Then, the half-wave rectifier circuit 23 obtains a half-wave rectified signal containing a preset number of sinusoidal half-waves according to the control command. When the controller 21 detects that the half-wave rectified signal starts to rise from the first preset voltage, it controls the target switch 24 to close and controls the power device under test 22 to conduct, so as to obtain the surge test result when the current passes between the drain and source electrodes of the power device under test 22. Since the power device under test 22 experiences a half-wave rectified signal containing a preset number of sinusoidal half-waves, the surge test can be automatically repeated on the power device under test 22 to obtain a surge test result containing a preset number of half-waves. For example, the controller 21 receives a test command sent by the computer device 20 and sends a control command containing a preset number of sine half-waves to the half-wave rectifier circuit 23 according to the test command. When the preset number is 5, the half-wave rectifier circuit 23 obtains a half-wave rectified signal containing 5 sine half-waves according to the control command containing 5 sine half-waves. Then, when the controller 21 detects that the half-wave rectified signal starts to rise from the first preset voltage, it controls the target switch 24 to close and controls the power device under test 22 to turn on. Since the half-wave rectified signal includes 5 sine half-waves, a total of 5 surge currents are formed, thereby obtaining a surge test result containing 5 surge tests to improve surge test efficiency.
[0043] In one embodiment, such as Figure 3 As shown, Figure 3 The circuit diagram of a surge testing device for a power device provided in this application embodiment is shown. The device further includes a first terminal of a target switch 24 connected to the first terminal of a half-wave rectifier circuit 23, a second terminal of the target switch 24 connected to the drain of the power device under test 22, and a third terminal of the target switch 24 connected to a controller 21.
[0044] The target switch 24 can be a high-speed switch or an N-type metal-oxide-semiconductor (NMOS) electronic switch. This embodiment does not make specific limitations on this, as long as it can control the conduction and cutoff of the half-wave rectifier circuit 23 and the power device under test 22.
[0045] In this embodiment, the device further includes a first terminal of the target switch 24 connected to the first terminal of the half-wave rectifier circuit 23, a second terminal of the target switch 24 connected to the drain of the power device under test 22, and a third terminal of the target switch 24 connected to the controller 21. That is, in this embodiment, the controller 21 controls the conduction of the half-wave rectifier circuit 23 and the power device under test 22 through the target switch 24, thereby enabling surge current testing of the power device under test 22.
[0046] In one embodiment, the apparatus further includes a gate of the power device under test 22 connected to the controller 21, and a source of the power device under test 22 grounded.
[0047] In one embodiment, the device further includes a current probe 35, with a first end of the current probe 35 grounded, a second end of the current probe 35 connected to the source of the power device under test 22, and a third end of the current probe 35 connected to the computer device 20.
[0048] In this implementation, combined with Figure 3 To explain, when the controller 21 detects the half-wave rectified signal rising from the first preset voltage of 0V, it controls the target switch 24 to close and controls the power device under test 22 to conduct, so that a surge current is formed when current passes between the drain and source electrodes of the power device under test 22, thereby obtaining the surge test result. The current probe 35 connected in series with the power device under test 22 measures the waveform of the surge current and stores it in the computer device 20. The surge test result includes the surge current test result. Optionally, the current probe 35 is a 200A AC / DC current probe.
[0049] In this embodiment, the device further includes a current probe 35. The first end of the current probe 35 is grounded, the second end of the current probe 35 is connected to the source electrode of the power device under test 22, and the third end of the current probe 35 is connected to the computer device 20. That is, in this embodiment, the surge test result of the surge current is obtained by detecting the current passing between the drain and source electrodes of the power device under test 22 through the current probe 35, thereby realizing the leakage current I of the experimental data source. ds Automatic data collection and preliminary processing.
[0050] In one embodiment, the device further includes a voltage probe 37, a first end of which is connected to the drain of the power device under test 22, a second end of which is connected to the source of the power device under test 22, and a third end of which is connected to the computer device 20.
[0051] In this implementation, combined with Figure 3 To explain, when the controller 21 detects the half-wave rectified signal rising from a first preset voltage of 0V, it controls the target switch 24 to close and controls the power device under test 22 to conduct, so that a surge current is formed when current passes through the drain-source electrodes of the power device under test 22, thereby obtaining the surge test result. The voltage probe 37 connected in parallel with the power device under test 22 measures the waveform of the surge voltage and stores it in the computer device 20. The surge test result includes the surge voltage test result. Optionally, the voltage probe 37 is a high-voltage differential probe.
[0052] In this embodiment, the device further includes a voltage probe 37. The first end of the voltage probe 37 is connected to the drain of the power device under test 22, the second end of the voltage probe 37 is connected to the source of the power device under test 22, and the third end of the voltage probe 37 is connected to the computer device 20. In other words, in this embodiment, the surge voltage test result is obtained by detecting the current passing between the drain and source electrodes of the power device under test 22 through the voltage probe 37, thereby realizing the leakage voltage V of the experimental data source. ds Automatic data collection and preliminary processing.
[0053] In one embodiment, the device further includes an oscilloscope 36, with the third end of the current probe 35 connected to the computer device 20 via the oscilloscope 36, and the third end of the voltage probe 37 connected to the computer device 20 via the oscilloscope 36.
[0054] Optionally, the oscilloscope 36 can be a 200MHz USB oscilloscope.
[0055] In this embodiment, the device further includes an oscilloscope 36. The third end of the current probe 35 is connected to the computer device 20 via the oscilloscope 36, and the third end of the voltage probe 37 is also connected to the computer device 20 via the oscilloscope 36. In other words, this embodiment uses the oscilloscope 36 to measure and record the value and waveform of the surge current and surge voltage, thereby transforming the invisible current and voltage signals into visible current and voltage curves, facilitating researchers' study of the changes in surge current and surge voltage.
[0056] Reference Figure 4 , Figure 4This is a schematic diagram of the internal structure of a controller provided in an embodiment of this application. The controller includes a detection circuit 43 and a processing circuit 41, with the detection circuit 43 connected to the processing circuit 41. The detection circuit 43 is used to detect the half-wave rectified signal to obtain a detection result and send the detection result to the processing circuit 41. The processing circuit 41 is used to control the target switch 24 to close and control the power device under test 22 to conduct when the detection result indicates that the half-wave rectified signal starts to rise from a first preset voltage.
[0057] In this embodiment, the detection circuit 43 sends the detection result obtained from detecting the half-wave rectified signal to the processing circuit 41. When the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage 0V, the processing circuit 41 controls the target switch 24 to close and controls the gate-source voltage V of the power device under test 22. gs The voltage is greater than the threshold voltage, causing the power device under test 22 to conduct.
[0058] In this embodiment, the controller 21 includes a detection circuit 43 and a processing circuit 41, with the detection circuit 43 connected to the processing circuit 41. The detection circuit 43 is used to detect the half-wave rectified signal, obtain a detection result, and send the detection result to the processing circuit 41. The processing circuit 41 is used to control the target switch 24 to close and control the power device under test 22 to conduct when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage. That is, because the detection circuit 43 and the processing circuit 41 are connected, the controller 21 can control the target switch 24 to close and control the power device under test 22 to conduct when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage.
[0059] In one embodiment, the controller 21 further includes a switch control circuit 39 and a grid voltage generation circuit 40, both of which are connected to the processing circuit 41. The switch control circuit 39 is used to receive the detection result sent by the processing circuit 41, and to control the target switch 24 to close when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage. The grid voltage generation circuit 40 is used to receive the detection result sent by the processing circuit 41, and to control the power device under test 22 to turn on when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage.
[0060] In this circuit, the switch control circuit 39 receives the detection result sent by the processing circuit 41, and when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage 0V, it controls the target switch 24 to close. At the same time, the gate voltage generation circuit 40 receives the detection result sent by the processing circuit 41, and when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage 0V, it controls the gate-source voltage V of the power device under test 22. gs The voltage is greater than the threshold voltage, causing the power device under test 22 to conduct.
[0061] In this embodiment, the controller 21 further includes a switch control circuit 39 and a grid voltage generation circuit 40, both of which are connected to the processing circuit. The switch control circuit 39 receives the detection result sent by the processing circuit 41 and controls the target switch 24 to close when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage. The grid voltage generation circuit 40 receives the detection result sent by the processing circuit 41 and controls the power device under test 22 to turn on when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage. In other words, since both the switch control circuit 39 and the grid voltage generation circuit 40 are connected to the processing circuit 41, the controller 21 can control the target switch 24 to close and the power device under test 22 to turn on.
[0062] In one embodiment, the controller 21 further includes an interface circuit 42 connected to the computer device 20 and also connected to the processing circuit 41. The interface circuit 42 is used to receive test commands sent by the computer device 20 and send test commands to the processing circuit 41, so that the processing circuit 41 can send control commands to the half-wave rectifier circuit 23 according to the test commands.
[0063] The interface circuit 42 receives a test command from the computer device 20 containing a preset number of surge tests, and sends the test command to the processing circuit 41. The processing circuit 41 then sends a control command containing a preset number of sinusoidal half-waves to the half-wave rectifier circuit 23 according to the test command, thereby obtaining a half-wave rectified signal.
[0064] In this embodiment, the controller 21 further includes an interface circuit 42, which is connected to the computer device 20 and also to the processing circuit 41. The interface circuit 42 is used to receive test commands sent by the computer device 20 and send test commands to the processing circuit 41, so that the processing circuit 41 can send control commands to the half-wave rectifier circuit 23 according to the test commands. That is, since the interface circuit 42 is connected to the computer device 20 and the processing circuit 41, the controller 21 can perform surge testing on the power device under test 22 according to the test commands sent by the computer device 20 to obtain the degree of performance degradation of the power device under test 22 after being subjected to a large current pulse.
[0065] In one embodiment, the half-wave rectifier circuit 23 includes an AC power supply 31, a first transformer 32, a second transformer 33, and a half-wave rectifier module 34. The two ends of the first transformer 32 are connected to the AC power supply 31, the second transformer 33 is connected in series with the first transformer 32, and the second transformer 33 is connected to the half-wave rectifier module 34. The first end of the half-wave rectifier module 34 is connected to the target switch 24, and the second end of the half-wave rectifier module 34 is connected to the controller.
[0066] In this embodiment, the AC power generated by the AC power supply 31 is converted into the surge voltage required for surge testing of the power device 22 under test by the first transformer 32, and then rectified by the half-wave rectifier module 34 after being transformed by the second transformer 33 into a half-wave rectified signal containing a preset number of sinusoidal half-waves. Optionally, the first transformer 32 is an electrically adjustable autotransformer T1, the second transformer 33 is an isolation transformer T2, and the half-wave rectifier module 34 is a 200A bridge rectifier. The electrically adjustable autotransformer T1 has a specification of 0-250V, and the isolation transformer T2 has a specification of 250V to 250V.
[0067] It should be noted that surge voltage and surge current are positively correlated.
[0068] In this embodiment, the half-wave rectifier circuit 23 includes an AC power supply 31, a first transformer 32, a second transformer 33, and a half-wave rectifier module 34. The two ends of the first transformer 32 are connected to the AC power supply 31. The second transformer 33 is connected in series with the first transformer 32 and is also connected to the half-wave rectifier module 34. The first end of the half-wave rectifier module 34 is connected to the target switch 24, and the second end is connected to the controller. In other words, in this example, the first transformer 32 converts the AC power into the surge voltage required for surge testing of the power device 22 under test. After being transformed by the second transformer 33, the half-wave rectifier module 34 rectifies the transformed surge voltage into a half-wave rectified signal.
[0069] Optionally, the device also includes a liquid crystal display (LCD) 38, which is connected to the computer device 20. The computer device 20 and the LCD 38 are used to set test parameters and display the test parameters and curves during the surge test. The specific test parameters are shown in Table 1. Before the test, the preset number n of each test sine wave half-wave and the number of test rounds m can be preset. Multiple rounds of repeated surge tests are performed based on the preset number n and the number of test rounds m of each test sine wave half-wave.
[0070] Table 1 Test Parameter Description
[0071]
[0072] To facilitate a clearer understanding of the surge testing device provided in this application by those skilled in the art, this application is combined with... Figure 5 A surge testing apparatus for power devices provided in another embodiment of this application will be described in detail. Figure 5 A circuit diagram of a surge testing device for a power device provided in another embodiment of this application. Figure 5The 220V AC power supply is AC power supply 31, the electrically adjustable autotransformer T1 is the first transformer 32, the isolation transformer T2 is the second transformer 33, the bridge rectifier is a half-wave rectifier module 34, the high-speed switch S1 is the target switch 24, the sinusoidal half-wave is the half-wave rectified signal, the central controller is controller 21, the computer PC is computer equipment 20, the current probe P1 is current probe 35, the high-voltage differential probe P2 is voltage probe 37, and the USB oscilloscope OP1 is oscilloscope 36. The host computer communication interface circuit is interface circuit 42, the MCU+FPGA processing unit is processing circuit 41, the grid voltage generation circuit of the device under test is grid voltage generation circuit 40, the zero-crossing detection circuit is detection circuit 43, and the high-speed switch control circuit is switch control circuit 39. Specifically, it includes the following steps:
[0073] The S501 220V AC mains power is converted into the surge voltage required for surge testing of the power device under test by the electrically adjustable autotransformer T1, and then rectified into a sinusoidal half-wave voltage by the bridge rectifier after being transformed by the isolation transformer T2.
[0074] The S502 central controller's host computer communication interface circuit receives test commands sent by the PC and sends test commands to the MCU+FPGA processing unit. The MCU+FPGA processing unit then sends control commands to the half-wave rectifier circuit based on these test commands. Here, FPGA stands for Field Programmable Gate Array, and MCU stands for Microcontroller Unit.
[0075] S503, the half-wave rectifier circuit obtains a sinusoidal half-wave according to the control command. When the high-speed switch control circuit receives the detection result of the zero-crossing detection circuit detecting that the sinusoidal half-wave of the voltage starts to rise from 0V, it controls the high-speed switch S1 to close.
[0076] S504. When the gate voltage generation circuit of the device under test receives the detection result of the zero-crossing detection circuit detecting that the sinusoidal half-wave of the voltage starts to rise from 0V, the gate-source voltage V of the power device under test is controlled. gs When the voltage exceeds the threshold voltage, the power device under test is turned on. When the current passes between the source and drain electrodes of the power device under test, the surge test result is obtained. The current probe P1 connected in series in the circuit and the high voltage differential probe P2 connected in parallel on both sides of the power device under test detect the surge current and surge voltage during the surge test and record the V / I curve, which is then stored in the computer PC.
[0077] S505. After the power device under test has experienced a preset number of sinusoidal half-waves, it means that a round of repeated surge current test has ended. The controller controls the high-speed switch S1 to open and controls the power device under test to turn off.
[0078] The surge testing device for the aforementioned power device includes a half-wave rectifier circuit, a controller, a power device under test (DUT), a target switch, and a computer. The controller receives test commands from the computer and sends control commands to the half-wave rectifier circuit according to the test commands. The half-wave rectifier circuit acquires a half-wave rectified signal according to the control commands, wherein the half-wave rectified signal includes a preset number of sinusoidal half-waves. The controller also controls the target switch to close and the DUT to conduct when it detects that the half-wave rectified signal is rising from a first preset voltage, so as to obtain surge test results when current passes between the drain and source electrodes of the DUT. In other words, in this embodiment, the controller receives test instructions sent by the computer device and sends control instructions to the half-wave rectifier circuit according to the test instructions. Then, the half-wave rectifier circuit obtains a half-wave rectified signal containing a preset number of sinusoidal half-waves according to the control instructions. When the controller detects that the half-wave rectified signal starts to rise from the first preset voltage, it controls the target switch to close and controls the power device under test to conduct, so as to obtain the surge test result when the current passes between the drain and source electrodes of the power device under test. Since the power device under test experiences a half-wave rectified signal containing a preset number of sinusoidal half-waves, the surge test can be automatically repeated on the power device under test to obtain a surge test result containing a preset number of half-waves. For example, the controller receives a test command sent by the computer device and sends a control command containing a preset number of sine half-waves to the half-wave rectifier circuit according to the test command. When the preset number is 5, the half-wave rectifier circuit obtains a half-wave rectified signal containing 5 sine half-waves according to the control command containing 5 sine half-waves. Then, when the controller detects that the half-wave rectified signal starts to rise from the first preset voltage, it controls the target switch to close and controls the power device under test to turn on. Since the half-wave rectified signal includes 5 sine half-waves, a total of 5 surge currents are formed, thereby obtaining a surge test result containing 5 surge tests, so as to improve the surge test efficiency.
[0079] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.
[0080] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.
[0081] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0082] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.
Claims
1. A surge testing device for power devices, characterized in that, The device includes a half-wave rectifier circuit, a controller, a power device under test, a target switch, and a computer device; the first terminal of the target switch is connected to the first terminal of the half-wave rectifier circuit, the second terminal of the target switch is connected to the drain of the power device under test, and the third terminal of the target switch is connected to the controller. The controller is configured to receive test commands sent by the computer device and send control commands to the half-wave rectifier circuit according to the test commands. The half-wave rectifier circuit is used to acquire a half-wave rectified signal according to the control command, wherein the half-wave rectified signal includes a preset number of sinusoidal half-waves. The controller is also configured to control the target switch to close and control the power device under test to turn on when the half-wave rectified signal is detected to rise from the first preset voltage, so as to obtain a preset number of surge test results when the current passes between the drain and source electrodes of the power device under test, so as to complete a surge test. The controller is also configured to, after completing one round of surge testing, control the target switch to open and control the power device under test to turn off.
2. The apparatus according to claim 1, characterized in that, The gate of the power device under test is connected to the controller, and the source of the power device under test is grounded.
3. The apparatus according to claim 1, characterized in that, The device also includes a current probe, the first end of which is grounded, the second end of which is connected to the source of the power device under test, and the third end of which is connected to the computer equipment.
4. The apparatus according to claim 3, characterized in that, The device further includes a voltage probe, the first end of which is connected to the drain of the power device under test, the second end of which is connected to the source of the power device under test, and the third end of which is connected to the computer equipment.
5. The apparatus according to claim 4, characterized in that, The device also includes an oscilloscope, with the third end of the current probe connected to the computer device via the oscilloscope, and the third end of the voltage probe connected to the computer device via the oscilloscope.
6. The apparatus according to claim 1, characterized in that, The controller includes a detection circuit and a processing circuit, and the detection circuit is connected to the processing circuit. The detection circuit is used to detect the half-wave rectified signal, obtain a detection result, and send the detection result to the processing circuit. The processing circuit is used to control the target switch to close and control the power device under test to conduct when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage.
7. The apparatus according to claim 6, characterized in that, The controller further includes a switch control circuit and a gate voltage generation circuit, both of which are connected to the processing circuit. The switch control circuit is used to receive the detection result sent by the processing circuit, and control the target switch to close when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage; The gate voltage generating circuit is used to receive the detection result sent by the processing circuit, and control the power device under test to turn on when the detection result indicates that the half-wave rectified signal starts to rise from the first preset voltage.
8. The apparatus according to claim 6, characterized in that, The controller further includes an interface circuit, which is connected to the computer device and also to the processing circuit. The interface circuit is used to receive test commands sent by the computer device and send the test commands to the processing circuit, so that the processing circuit can send control commands to the half-wave rectifier circuit according to the test commands.
9. The apparatus according to any one of claims 1-8, characterized in that, The half-wave rectifier circuit includes an AC power supply, a first transformer, a second transformer, and a half-wave rectifier module. The two ends of the first transformer are connected to the AC power supply. The second transformer is connected in series with the first transformer and is connected to the half-wave rectifier module. The first end of the half-wave rectifier module is connected to the target switch, and the second end of the half-wave rectifier module is connected to the controller.
10. The apparatus according to any one of claims 1-8, characterized in that, The computer device limits the interval time of each surge test to n / m, where n is the preset number and m is the number of surge tests.