Control method and device of double-pulse testing device, testing system and storage medium

Abstract

The invention provides a control method and device of a double-pulse testing device, a testing system and a storage medium, and relates to the technical field of electronic device testing. The method comprises the following steps: sending a first pulse to a to-be-tested IGBT device; the first pulse is used for controlling the to-be-tested IGBT device to be turned off after saturation conduction; continuously sending a plurality of second pulses to the to-be-measured IGBT device until the device temperature of the to-be-measured IGBT device rises to the target temperature, and measuring the switching characteristic of the to-be-measured IGBT device at the target temperature; wherein the pulse width of the second pulse is smaller than that of the first pulse, and the to-be-tested IGBT device works in a linear region within the duration of the pulse width of the second pulse. According to the invention, the performance test of the IGBT device in the high-temperature state can be realized by using the double-pulse test device.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic device testing, and in particular to a control method, device, test system and storage medium of a double pulse test device. Background Art

[0002] As inverter power continues to increase, performance requirements for the insulated-gate bipolar transistor (IGBT), the main power device within the inverter, are increasing. Correspondingly, performance testing requirements for IGBT devices are becoming increasingly stringent.

[0003] In related technologies, dual-pulse testing devices are often used to perform performance tests on IGBT devices, thereby assessing whether the IGBT device's performance meets standards. The dual-pulse testing device uses the first pulse to set the operating current of the IGBT device, placing the IGBT device in a high-voltage, high-current, and thermally stable state to be tested, providing a test basis for the second pulse. Based on the first pulse, a second pulse is sent to switch the IGBT device between the off and on states, thereby measuring the switching characteristics of the IGBT device. Using two pulse signals, the dual-pulse testing device can perform performance tests on IGBT devices at room temperature.

[0004] However, the IGBT devices inside high-power inverters usually operate at high temperatures during actual operation, and existing double-pulse test devices are unable to test the performance of IGBT devices under high temperature conditions. Summary of the Invention

[0005] The embodiments of the present invention provide a control method, device, test system and storage medium of a double pulse test device to solve the problem that the double pulse test device cannot test the performance of an IGBT device under a high temperature state.

[0006] In a first aspect, an embodiment of the present invention provides a control method for a dual-pulse test device, which is applied to the dual-pulse test device, wherein the dual-pulse test device is connected to an IGBT device to be tested, and the method includes:

[0007] Sending a first pulse to the IGBT device under test; the first pulse is used to control the IGBT device under test to be turned off after being saturated;

[0008] Multiple second pulses are continuously sent to the IGBT device under test until the device temperature of the IGBT device under test rises to a target temperature, and the switching characteristics of the IGBT device under test at the target temperature are measured; wherein the pulse width of the second pulse is smaller than the pulse width of the first pulse, and during the duration of the pulse width of the second pulse, the IGBT device under test operates in a linear region.

[0009] In a possible implementation, continuously sending a plurality of second pulses to the IGBT device under test until the device temperature of the IGBT device under test rises to a target temperature, and measuring the switching characteristics of the IGBT device under test at the target temperature includes:

[0010] Sending a set number of second pulses at a set pulse interval to collect the device temperature of the IGBT device to be tested in real time and detecting whether the device temperature reaches the target temperature;

[0011] If the device temperature does not reach the target temperature, updating the set number according to the difference between the device temperature and the target temperature, and skipping to execute the step of sending the set number of second pulses according to the set pulse interval;

[0012] If the device temperature reaches the target temperature, the switching characteristics of the IGBT device to be tested at the target temperature are measured.

[0013] In a possible implementation, updating the set quantity according to the difference between the device temperature and the target temperature includes:

[0014] Obtaining a temperature rise value of the IGBT device under test, and determining a pulse temperature rise rate based on a ratio of the temperature rise value to the set number; the temperature rise value is a temperature difference between the device temperature of the IGBT device under test before and after sending a set number of second pulses at a set pulse interval;

[0015] The set quantity is re-determined according to the difference between the device temperature and the target temperature, and the pulse temperature rise rate.

[0016] In a possible implementation, continuously sending a plurality of second pulses to the IGBT device under test until the device temperature of the IGBT device under test rises to a target temperature, and measuring the switching characteristics of the IGBT device under test at the target temperature includes:

[0017] Continuously sending a plurality of second pulses to the IGBT device under test according to a set pulse interval and a set pulse voltage value until the device temperature of the IGBT device under test rises to a set temperature, and then reducing the set pulse voltage value to a DC bus voltage of the IGBT device under test in an actual working state; the set pulse voltage value is greater than the DC bus voltage of the IGBT device under test in an actual working state;

[0018] A second pulse after voltage reduction is sent to the IGBT device under test according to the set pulse interval until the device temperature reaches the target temperature, and the switching characteristics of the IGBT device under test at the target temperature are measured; the set temperature is lower than the target temperature, and the difference between the target temperature and the set temperature is lower than a set threshold.

[0019] In a possible implementation, after the temperature of the device rises to the target temperature, the method further includes:

[0020] detecting whether the temperature of the device decreases;

[0021] If the device temperature drops, the cooling time of the IGBT device to be tested is detected; the cooling time is the time interval for the device temperature to drop from the target temperature to the current temperature;

[0022] If the cooling time is less than or equal to the set time interval, sending multiple second pulses to maintain the device temperature at the target temperature; the set time interval is greater than the set pulse interval;

[0023] If the cooling time is longer than the set time interval, sending a first pulse and a plurality of second pulses to maintain the device temperature at the target temperature;

[0024] The operating time of the IGBT device to be tested at the target temperature is measured.

[0025] In a possible implementation, when the device temperature is maintained at the target temperature, the method further includes:

[0026] Increasing the pulse width of the first pulse to increase the operating current of the IGBT device to be tested;

[0027] Resending the first pulse and the second pulse to measure the operating performance of the IGBT device to be tested under the current operating current;

[0028] Detecting whether the working performance of the IGBT device to be tested fails under the current working current;

[0029] If the working performance of the IGBT device to be tested has not failed, jump to the step of increasing the pulse width of the first pulse;

[0030] If the operating performance of the IGBT device under test fails at the current operating current, the limiting operating current of the IGBT device under test at the target temperature is determined according to the current operating current of the IGBT device under test.

[0031] In a possible implementation, the double-pulse test device has more than one output terminal, each of which is used to be connected to each IGBT device under test in the same device under test. The method further includes:

[0032] Determining the test requirements of each IGBT device under test based on the circuit topology of the device under test;

[0033] Based on the test requirements of each IGBT device to be tested, each test interface of the double-pulse test device is controlled to output a different first pulse and second pulse.

[0034] In a second aspect, an embodiment of the present invention provides a control device for a double-pulse test device, which is applied to the double-pulse test device. The double-pulse test device is used to connect to an IGBT device to be tested, and the device includes:

[0035] The first module is configured to send a first pulse to the IGBT device under test; the first pulse is configured to control the IGBT device under test to be turned off after being saturated and turned on;

[0036] The second module is configured to continuously send multiple second pulses to the IGBT device under test until the device temperature of the IGBT device under test rises to a target temperature, and then measure the switching characteristics of the IGBT device under test at the target temperature; wherein the pulse width of the second pulse is less than the pulse width of the first pulse, and during the duration of the pulse width of the second pulse, the IGBT device under test operates in a linear region. In a third aspect, an embodiment of the present invention provides a test system comprising a dual-pulse test apparatus and a conversion board;

[0037] The dual-pulse test device is connected to the IGBT device to be tested via the conversion board; the conversion board is provided with a plurality of test interfaces respectively connected to the output terminals of the dual-pulse test device, and drive interfaces respectively connected to the IGBT devices to be tested, and each test interface is correspondingly connected to each drive interface;

[0038] The double-pulse testing device is used to implement the method in the first aspect or any possible implementation of the first aspect.

[0039] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the method in the first aspect or any possible implementation of the first aspect.

[0040] In an embodiment of the present invention, the IGBT device under test is saturated and then turned off by a first pulse. While the IGBT device under test is in the off state, multiple second pulses are continuously sent to maintain the IGBT device under test in a constant state of switching between the off and on states, thereby causing the IGBT device under test to generate switching losses in an incompletely on state (i.e., the Miller plateau). Switching losses are a major factor affecting the temperature rise of IGBT devices within the inverter. By continuously sending multiple second pulses, the embodiment of the present invention can rapidly heat the IGBT device under test to the target temperature, thereby enabling IGBT device performance testing under high-temperature conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a test architecture diagram for testing IGBT devices using a double-pulse test device.

[0042] Figure 2 1. It is a pulse schematic diagram of a double pulse test device sending a first pulse and a second pulse in the related art;

[0043] Figure 3 This is a flow chart of an implementation method of a double pulse test device provided by an embodiment of the present invention;

[0044] Figure 4 1 is a pulse diagram of a double pulse test device according to an embodiment of the present invention sending a first pulse and a second pulse;

[0045] Figure 5 is a schematic structural diagram of a test system provided by an embodiment of the present invention;

[0046] Figure 6 It is a structural schematic diagram of a control device of a double-pulse test device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0048] See also Figure 1 and Figure 2Based on the dual-pulse test device connected to the IGBT device, two pulse signals (first pulse and second pulse) can be used to test the performance of the IGBT device. The first pulse can set the operating current of the IGBT device, so that the IGBT device is in a high-voltage, high-current, thermally stable saturated conduction state and then turns off, thereby measuring the saturated conduction characteristics and turn-off characteristics of the IGBT device. At the same time, the first pulse also provides a test basis for the second pulse. Based on the first pulse, the second pulse is sent to switch the IGBT device between the off state and the on state, thereby measuring the switching characteristics of the IGBT device.

[0049] Most related technologies use dual-pulse testing devices to test the performance of IGBT devices at room temperature. However, the IGBT devices inside high-power inverters typically operate at higher temperatures during operation. Existing dual-pulse testing devices are unable to test the performance of IGBT devices at high temperatures.

[0050] Based on the idea of ​​using a dual-pulse test device to realize the performance test of IGBT devices under high temperature conditions, the embodiment of the present invention uses the dual-pulse test device to continuously send multiple second pulses, which can make the IGBT device to be tested always in the switching process between the off state and the on state, so that the IGBT device to be tested generates switching loss in the incomplete conduction state (i.e., Miller platform), promotes the IGBT device to quickly heat up to the target temperature, thereby realizing the performance test of the IGBT device under high temperature conditions.

[0051] The control method of the double pulse test device provided in the embodiment of the present invention is applied to the double pulse test device, which is used to connect to the IGBT device to be tested. Figure 3 , which shows a flow chart of the control method for the double pulse test device, which is described in detail as follows:

[0052] Step 301: Send a first pulse to the IGBT device to be tested.

[0053] After the dual-pulse test device is connected to the IGBT device under test, it sends a first pulse to the IGBT device under test. During the duration of the first pulse, the operating current of the IGBT device under test increases linearly until the operating current of the IGBT device under test reaches the set operating current. At this point, the first pulse is turned off, shutting down the IGBT device under test.

[0054] Here, the operating current setting can be determined based on actual conditions and is not specifically limited in the present embodiment. It is understood that the operating current of the IGBT device under test after saturation conduction can be determined by the pulse width of the first pulse. The greater the pulse width of the first pulse, the greater the operating current of the IGBT device under test after saturation conduction.

[0055] The dual-pulse tester uses the first pulse to saturate the IGBT device under test and reach the set operating current, thereby measuring the IGBT's conduction performance at the set operating current. For example, the on-state saturation voltage drop and the thermal resistance in the saturated on-state (which can be used to calculate the junction temperature) are measured. When the IGBT reaches the set operating current, the first pulse is removed, shutting down the IGBT. At this point, the IGBT's turn-off characteristics, such as its turn-off delay time and the forward voltage drop of its internal freewheeling diode, can be measured.

[0056] Here, the first pulse can control the IGBT device under test to be saturated and then turned off, thereby providing a test basis for the second pulse, so that the second pulse can test the switching characteristics of the IGBT device under test.

[0057] Step 302 : Continuously send multiple second pulses to the IGBT device under test until the device temperature of the IGBT device under test rises to a target temperature, and then measure the switching characteristics of the IGBT device under test at the target temperature. The pulse width of the second pulse is shorter than the pulse width of the first pulse, and the IGBT device under test operates in a linear region during the duration of the second pulse.

[0058] After the first pulse is turned off, the IGBT device under test turns off, generating a freewheeling current within the freewheeling diode within the IGBT device under test. At this point, the dual-pulse tester sends a second pulse to the IGBT device under test, which switches the device from the off state to the on state. Turning on the IGBT device under test forces the freewheeling diode to reverse-turn off, triggering reverse recovery. The freewheeling current within the diode generates a reverse recovery current, resulting in reverse recovery losses.

[0059] Here, when the IGBT device under test switches from the off state to the on state, turn-on loss is generated, of which reverse recovery loss is a part of the turn-on loss.

[0060] After the second pulse is turned off, the IGBT device under test switches from the on state to the off state, generating turn-off loss. Here, the sum of the turn-on loss and the turn-off loss is the switching loss of the IGBT device under test.

[0061] The double-pulse test device can synchronously measure the switching characteristics of the IGBT device under test, such as turn-on loss, turn-off loss and diode reverse recovery current, by sending the second pulse.

[0062] See also Figure 4In an embodiment of the present invention, multiple second pulses are continuously sent to heat the IGBT device under test, based on the first pulse. Switching loss is a major factor affecting the temperature rise of IGBT devices within the inverter. By continuously sending multiple second pulses to the IGBT device under test based on the first pulse, the embodiment of the present invention can keep the IGBT device under test in a state of constant switching between the off state and the on state, repeatedly generating switching losses, thereby heating the IGBT device under test.

[0063] It is important to note that the pulse width of the second pulse is smaller than that of the first pulse, and that the IGBT device under test operates in its linear region during the duration of the second pulse. The second pulse width is typically relatively small, typically in the microsecond range. In embodiments of the present invention, the second pulse width can be set to the shortest possible pulse width while capturing the complete switching process. This allows the IGBT device under test to operate in its linear region, preventing it from entering a saturated conduction state and introducing conduction losses, which could affect the accuracy of switching loss measurements.

[0064] In an embodiment of the present invention, a dual-pulse test apparatus continuously transmits multiple second pulses to raise the temperature of the IGBT device under test to a target temperature. After the IGBT device under test reaches the target temperature, the dual-pulse test apparatus transmits another second pulse to measure the switching characteristics of the IGBT device under test at the target temperature. Alternatively, within the allowable temperature error range, the switching characteristics measured with the last second pulse of the multiple consecutive second pulses can be used as the switching characteristics of the IGBT device under test at the target temperature.

[0065] In an embodiment of the present invention, the IGBT device under test is saturated and then turned off by a first pulse. While the IGBT device under test is in the off state, multiple second pulses are continuously sent to maintain the IGBT device under test in a constant state of switching between the off and on states, thereby causing the IGBT device under test to generate switching losses in an incompletely on state (i.e., the Miller plateau). Switching losses are a major factor affecting the temperature rise of IGBT devices within the inverter. By continuously sending multiple second pulses, the embodiment of the present invention can rapidly heat the IGBT device under test to the target temperature, thereby enabling IGBT device performance testing under high-temperature conditions.

[0066] The specific implementation of continuously sending multiple second pulses is introduced below.

[0067] In some embodiments, a set number of second pulses can be sent according to a set pulse interval first, the device temperature of the IGBT device to be tested can be collected in real time, and whether the device temperature reaches the target temperature can be detected; if the device temperature does not reach the target temperature, the set number is updated according to the difference between the device temperature and the target temperature, and the step of sending a set number of second pulses according to the set pulse interval is jumped to be executed; if the device temperature reaches the target temperature, the switching characteristics of the IGBT device to be tested at the target temperature are measured.

[0068] The embodiment of the present invention can continuously send second pulses to the IGBT device under test according to the set pulse interval and the initial set number, and monitor the device temperature in real time during the sending process. If the device temperature does not reach the target temperature after the set number of second pulses are sent, the set number can be updated according to the difference between the current device temperature and the target temperature, and the set number of second pulses can be sent again according to the set pulse interval. This cycle is iterated, and the set number of second pulses are repeatedly sent until the device temperature reaches the target temperature, and the switching characteristics of the IGBT device under test at the target temperature are measured.

[0069] If the device temperature reaches the target temperature during the process of sending a set number of second pulses according to the set pulse interval, the sending of the second pulses is suspended when the device temperature reaches the target temperature, and the switching characteristics measured by the previous second pulse are used as the switching characteristics of the IGBT device to be tested at the target temperature.

[0070] Alternatively, after sending the set number of second pulses, the IGBT device under test is allowed to cool naturally to the target temperature, and then the switching characteristics of the IGBT device under test at the target temperature are measured. If the natural cooling time of the IGBT device under test is long (e.g., longer than the set time interval), the first pulse and the second pulse are resent to measure the switching characteristics of the IGBT device under test at the target temperature. If the natural cooling time of the IGBT device under test is short (e.g., less than or equal to the set time interval), the second pulse is sent to measure the switching characteristics of the IGBT device under test at the target temperature.

[0071] Here, the set time interval is greater than the set pulse interval. The specific length of the set time interval can be determined according to actual conditions, and the embodiment of the present invention does not make any specific limitation on this.

[0072] If the natural cooling time is long, there is no freewheeling current in the freewheeling diode of the IGBT device under test. In this case, the first and second pulses must be resent so that the switching characteristics can be measured with the second pulse. If the natural cooling time is short, there is still freewheeling current in the freewheeling diode of the IGBT device under test. In this case, only the second pulse is required to measure the switching characteristics.

[0073] Here, the pulse interval can be set according to the characteristics of the IGBT device to be tested. For example, the pulse interval can be set in a range of 1 to 10 microseconds.

[0074] The initial set number can be set according to the target temperature. It is understood that the higher the target temperature, the larger the initial set number.

[0075] In some embodiments, when updating the set number, the temperature rise value of the IGBT device to be tested can be obtained first, and the pulse temperature rise rate can be determined based on the ratio of the temperature rise value to the set number; then the set number can be re-determined based on the difference between the device temperature and the target temperature, as well as the pulse temperature rise rate.

[0076] Here, the temperature rise value is the temperature difference between the device temperature of the IGBT device to be tested before and after the second pulse of the set number is sent according to the set pulse interval;

[0077] In this embodiment of the present invention, the device temperature of the IGBT device under test is collected before and after sending a set number of second pulses at a set pulse interval. The temperature rise value is calculated by calculating the difference in device temperature. The ratio of the temperature rise value to the set number is then determined as the pulse temperature rise rate. Finally, the difference between the current device temperature and the target temperature is calculated, and the ratio of this difference to the pulse temperature rise rate is calculated to obtain a new set number. The second pulse is then resent according to the new set number until the device temperature reaches the target temperature.

[0078] In the embodiment of the present invention, during the process of sending the second pulse, the set number is updated according to the difference between the device temperature and the target temperature, and the number of second pulses sent can be dynamically adjusted in real time, thereby avoiding waste of pulse resources while controlling the IGBT device to be tested to reach the target temperature.

[0079] On the basis of the above embodiment, the embodiment of the present invention further provides another implementation method of continuously sending multiple second pulses to increase the temperature rise rate of the IGBT device to be tested.

[0080] In some embodiments, multiple second pulses can be continuously sent to the IGBT device under test according to a set pulse interval and a set pulse voltage value until the device temperature of the IGBT device under test rises to the set temperature, and then the set pulse voltage value is reduced to the DC bus voltage of the IGBT device under test in the actual working state; then, a second pulse with reduced voltage is sent to the IGBT device under test according to the set pulse interval until the device temperature reaches the target temperature, and then the switching characteristics of the IGBT device under test at the target temperature are measured.

[0081] Here, the pulse voltage is set to a value greater than the DC bus voltage of the IGBT device under test in its actual operating state. The set temperature is lower than the target temperature, and the difference between the target temperature and the set temperature is lower than a set threshold. The set threshold can be determined based on actual conditions and is not specifically limited in this embodiment of the present invention. For example, the set threshold can range from 5°C to 10°C.

[0082] It should be noted that the greater the pulse voltage value of the second pulse, the greater the switching loss of the IGBT device under test. In the early stage of temperature rise, in order to increase the temperature rise rate of the IGBT device under test, the embodiment of the present invention can use a larger pulse voltage value (i.e., set the pulse voltage value) to send the second pulse to increase the switching loss, thereby increasing the temperature rise rate of the IGBT device under test. In the later stage of temperature rise, in order to avoid the measurement accuracy of the switching characteristics of the IGBT device under test at the target temperature, the pulse voltage of the second pulse is restored to the DC bus voltage of the IGBT device under test in the actual working state.

[0083] In related technologies, when a dual-pulse test device uses the second pulse to measure the switching characteristics of the IGBT device under test, the pulse voltage of the second pulse is the DC bus voltage of the IGBT device under test in the actual working state to ensure the measurement accuracy of the switching characteristics.

[0084] In addition, the double-pulse test device can also be used to measure the operating time of the IGBT device under test at the target temperature, and to evaluate the operating reliability of the IGBT device under test at the target temperature.

[0085] In some embodiments, after the device temperature rises to the target temperature, the following steps may be performed to measure the operating time of the IGBT device under test at the target temperature:

[0086] Detect whether the device temperature has dropped. If so, detect the cooling time of the IGBT device under test. If the cooling time is less than or equal to the set time interval, send multiple second pulses to maintain the device temperature at the target temperature. If the cooling time is greater than the set time interval, send the first pulse and multiple second pulses to maintain the device temperature at the target temperature. Measure the operating time of the IGBT device under test at the target temperature. The cooling time is the time interval for the device temperature to drop from the target temperature to the current temperature.

[0087] Here, the set time interval is greater than the set pulse interval. The specific length of the set time interval can be determined according to actual conditions, and the embodiment of the present invention does not make any specific limitation on this.

[0088] If the cooling time is less than or equal to the set time interval, it indicates that freewheeling current is still flowing in the freewheeling diode of the IGBT device under test. In this case, the second pulse can be used to directly control the IGBT device under test to switch between the off state and the on state, generating switching losses to increase the temperature of the IGBT device under test.

[0089] When the cooling time is longer than the set time interval, it indicates that the freewheeling current in the freewheeling diode of the IGBT device under test no longer exists. In this case, it is necessary to first use the first pulse to control the IGBT device under test to be in the test state (in the test state, the freewheeling current in the freewheeling diode of the IGBT device under test exists). Then, multiple second pulses are continuously sent to control the IGBT device under test to switch between the off state and the on state, generating switching losses, thereby heating the IGBT device under test.

[0090] The embodiment of the present invention maintains the IGBT device under test at a target temperature by sending multiple second pulses or sending a first pulse and multiple second pulses, so as to measure the operating time of the IGBT device under test at the target temperature and evaluate the reliability of the IGBT device under test at the target temperature.

[0091] In some embodiments, the double pulse test apparatus may also be used to measure the limiting operating current of the IGBT device under test at a target temperature.

[0092] Specifically, when the device temperature is maintained at the target temperature, the pulse width of the first pulse can also be increased to increase the operating current of the IGBT device to be tested; the first pulse and the second pulse are resent to measure the operating performance of the IGBT device to be tested under the current operating current; and it is detected whether the operating performance of the IGBT device to be tested under the current operating current fails; if the operating performance of the IGBT device to be tested does not fail, then the step of increasing the pulse width of the first pulse is jumped to execute; if the operating performance of the IGBT device to be tested fails under the current operating current, then the limit operating current of the IGBT device to be tested at the target temperature is determined based on the current operating current of the IGBT device to be tested.

[0093] Under the premise that the device temperature is maintained at the target temperature, embodiments of the present invention increase the operating current of the IGBT device under test by increasing the pulse width of the first pulse. By sending the first pulse and the second pulse, the operating performance of the IGBT device under test, such as the saturated conduction characteristics, the turn-off characteristics, and the switching characteristics, can be measured at the current operating current. If the aforementioned operating performance has not failed, the pulse width of the first pulse is further increased, and the first pulse and the second pulse are resent. This cycle is repeated until the operating performance of the IGBT device under test fails. The maximum operating current of the IGBT device under test before failure is determined as the limiting operating current of the IGBT device under test at the target temperature.

[0094] Most IGBT devices are installed inside the inverter. In order to achieve performance testing of the IGBT devices inside the inverter, in some embodiments, the number of output terminals of the double-pulse test device is greater than 1, which is used to respectively connect each IGBT device to be tested inside the same device to be tested (such as an inverter).

[0095] It is understandable that when a performance test is performed on one IGBT device within the same device under test, the remaining IGBT devices must cooperate with each other. Furthermore, when the circuit topology of the device under test is different, the cooperation mode (for example, working state) of each IGBT device is different.

[0096] When performing performance testing on each IGBT device under test in the same device under test, the test requirements of each IGBT under test can be determined based on the circuit topology of the device under test, and based on the test requirements of each IGBT device under test, the test interfaces of the dual-pulse test device can be controlled to output different first pulses and second pulses to control the working state of each IGBT device under test.

[0097] Here, the test requirements for each IGBT device under test can be simply understood as: when testing one of the IGBT devices under test, it is necessary to control the operating state of each IGBT device under test. The dual-pulse test device can control the operating state (i.e., on / off state) of the IGBT device by sending a first pulse and / or a second pulse.

[0098] See also Figure 5 , based on the control method of the above-mentioned double pulse test device, an embodiment of the present invention further provides a test system, comprising: a double pulse test device 51 and a conversion board 52;

[0099] The double pulse test device 51 is connected to an IGBT device 53 to be tested via a conversion board 52 .

[0100] The conversion board 52 is provided with a plurality of test interfaces 521 connected to the output terminals of the double pulse test device 51, and drive interfaces 522 connected to the IGBT devices 53 to be tested. The test interfaces 521 and the drive interfaces 522 are connected to each other.

[0101] The double-pulse test device 51 is used to implement the control method of the double-pulse test device described above.

[0102] The embodiment of the present invention takes into account that the interface types of the IGBT devices to be tested on the devices to be tested of different models are different, and even the interfaces of the IGBT devices to be tested at different positions within the same device to be tested are different. In order to solve the interface adaptation problem of the dual-pulse test device, the embodiment of the present invention provides a conversion board, the test interface on the conversion board is used to adapt and connect to the output end of the dual-pulse test device, and the drive interface on the conversion board is used to adapt and connect to each IGBT device to be tested, and the test interface and the drive interface are connected correspondingly, thereby realizing interface conversion, so that the dual-pulse test device can adapt to devices to be tested of different models.

[0103] In some embodiments, the air-core inductor inside the double-pulse test device may also be placed on a conversion board so that the user can adjust the inductance value of the air-core inductor in real time.

[0104] The inductance of the air-core inductor also affects the operating current of the IGBT device under test. The user can control the operating current of the IGBT device under test by adjusting the pulse width of the first pulse or adjusting the inductance of the air-core inductor.

[0105] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0106] The following are device embodiments of the present invention. For details not fully described therein, reference may be made to the corresponding method embodiments described above.

[0107] Figure 6 A schematic diagram of the structure of a control device for a double pulse test device provided by an embodiment of the present invention is shown. For ease of explanation, only the portion related to the embodiment of the present invention is shown, which is described in detail as follows:

[0108] like Figure 6 As shown, the control device 6 of the double-pulse test device includes a first module 61 and a second module 62 .

[0109] The first module 61 is used to send a first pulse to the IGBT device under test; the first pulse is used to control the IGBT device under test to be turned off after saturation conduction;

[0110] The second module 62 is used to continuously send multiple second pulses to the IGBT device under test until the device temperature of the IGBT device under test rises to the target temperature, and measure the switching characteristics of the IGBT device under test at the target temperature; wherein the pulse width of the second pulse is smaller than the pulse width of the first pulse, and during the duration of the pulse width of the second pulse, the IGBT device under test operates in the linear region.

[0111] In a possible implementation, the second module 62 is specifically configured to:

[0112] Sending a set number of second pulses at a set pulse interval to collect the device temperature of the IGBT device to be tested in real time and detect whether the device temperature reaches the target temperature;

[0113] If the device temperature does not reach the target temperature, the set number is updated according to the difference between the device temperature and the target temperature, and the execution jumps to the step of sending the set number of second pulses according to the set pulse interval;

[0114] If the device temperature reaches the target temperature, the switching characteristics of the IGBT device under test at the target temperature are measured.

[0115] In a possible implementation, the second module 62 is specifically configured to:

[0116] Obtaining a temperature rise value of the IGBT device under test, and determining a pulse temperature rise rate based on a ratio of the temperature rise value to a set number; the temperature rise value is a temperature difference between the device temperature of the IGBT device under test before and after sending a set number of second pulses according to a set pulse interval;

[0117] The set quantity is re-determined based on the difference between the device temperature and the target temperature, as well as the pulse temperature rise rate.

[0118] In a possible implementation, the second module 62 is specifically configured to:

[0119] Continuously sending a plurality of second pulses to the IGBT device under test according to a set pulse interval and a set pulse voltage value until the device temperature of the IGBT device under test rises to a set temperature, and then reducing the set pulse voltage value to a DC bus voltage of the IGBT device under test in an actual working state; the set pulse voltage value is greater than the DC bus voltage of the IGBT device under test in an actual working state;

[0120] A second pulse after voltage reduction is sent to the IGBT device under test according to a set pulse interval until the device temperature reaches a target temperature, and the switching characteristics of the IGBT device under test at the target temperature are measured; the set temperature is lower than the target temperature, and the difference between the target temperature and the set temperature is lower than a set threshold.

[0121] In a possible implementation, the second module 62 is further configured to:

[0122] Detect whether the device temperature drops;

[0123] If the device temperature drops, the cooling time of the IGBT device to be tested is detected; the cooling time is the time interval for the device temperature to drop from the target temperature to the current temperature;

[0124] If the cooling time is less than or equal to the set time interval, multiple second pulses are sent to maintain the device temperature at the target temperature; the set time interval is greater than the set pulse interval;

[0125] If the cooling time is longer than the set time interval, the first pulse and multiple second pulses are sent to maintain the device temperature at the target temperature;

[0126] Measure the operating time of the IGBT device under test at the target temperature.

[0127] In a possible implementation, the second module 62 is further configured to:

[0128] Increasing the pulse width of the first pulse to increase the operating current of the IGBT device to be tested;

[0129] Resending the first pulse and the second pulse to measure the operating performance of the IGBT device under the current operating current;

[0130] Detect whether the working performance of the IGBT device under test fails under the current working current;

[0131] If the working performance of the IGBT device to be tested has not failed, the process jumps to the step of increasing the pulse width of the first pulse;

[0132] If the working performance of the IGBT device under test fails at the current working current, the limit working current of the IGBT device under test at the target temperature is determined according to the current working current of the IGBT device under test.

[0133] In a possible implementation, the double-pulse test device has more than one output terminal, which is used to connect to each IGBT device under test in the same device under test.

[0134] The second module 62 is further configured to:

[0135] Determine the test requirements for each IGBT device under test based on the circuit topology of the device under test;

[0136] Based on the test requirements of each IGBT device to be tested, each test interface of the double-pulse test device is controlled to output a different first pulse and second pulse.

[0137] This device embodiment can be used to implement the above method embodiment. Its technical principles and implementation effects are the same as those of the above method embodiment, and will not be repeated here.

[0138] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the scope of protection of the present invention.

Claims

1. A control method for a double pulse test device, characterized in that: Applied to the double pulse test device, the double pulse test device is used to be connected to the IGBT device to be tested, and the method includes: Sending a first pulse to the IGBT device under test; the first pulse is used to control the IGBT device under test to be turned off after being saturated; Multiple second pulses are continuously sent to the IGBT device under test until the device temperature of the IGBT device under test rises to a target temperature, and the switching characteristics of the IGBT device under test at the target temperature are measured; wherein the pulse width of the second pulse is smaller than the pulse width of the first pulse, and during the duration of the pulse width of the second pulse, the IGBT device under test operates in a linear region.

2. The control method of the double pulse test device according to claim 1, characterized in that: The step of continuously sending a plurality of second pulses to the IGBT device under test until the device temperature of the IGBT device under test rises to a target temperature, and measuring the switching characteristics of the IGBT device under test at the target temperature, comprises: Sending a set number of second pulses at a set pulse interval to collect the device temperature of the IGBT device to be tested in real time and detecting whether the device temperature reaches the target temperature; If the device temperature does not reach the target temperature, updating the set number according to the difference between the device temperature and the target temperature, and skipping to execute the step of sending the set number of second pulses according to the set pulse interval; If the device temperature reaches the target temperature, the switching characteristics of the IGBT device to be tested at the target temperature are measured.

3. The control method of the double pulse test device according to claim 2, characterized in that: The updating of the set quantity according to the difference between the device temperature and the target temperature includes: Obtaining a temperature rise value of the IGBT device under test, and determining a pulse temperature rise rate based on a ratio of the temperature rise value to the set number; the temperature rise value is a temperature difference between the device temperature of the IGBT device under test before and after sending a set number of second pulses at a set pulse interval; The set quantity is re-determined according to the difference between the device temperature and the target temperature, and the pulse temperature rise rate.

4. The control method of the double pulse test device according to claim 1, characterized in that: The step of continuously sending a plurality of second pulses to the IGBT device under test until the device temperature of the IGBT device under test rises to a target temperature, and measuring the switching characteristics of the IGBT device under test at the target temperature, comprises: Continuously sending a plurality of second pulses to the IGBT device under test according to a set pulse interval and a set pulse voltage value until the device temperature of the IGBT device under test rises to a set temperature, and then reducing the set pulse voltage value to a DC bus voltage of the IGBT device under test in an actual working state; the set pulse voltage value is greater than the DC bus voltage of the IGBT device under test in an actual working state; A second pulse after voltage reduction is sent to the IGBT device under test according to the set pulse interval until the device temperature reaches the target temperature, and the switching characteristics of the IGBT device under test at the target temperature are measured; the set temperature is lower than the target temperature, and the difference between the target temperature and the set temperature is lower than a set threshold.

5. The control method of the double pulse test device according to any one of claims 1 to 4, characterized in that: After the device temperature rises to the target temperature, the method further comprises: detecting whether the temperature of the device decreases; If the device temperature drops, the cooling time of the IGBT device to be tested is detected; the cooling time is the time interval for the device temperature to drop from the target temperature to the current temperature; If the cooling time is less than or equal to the set time interval, sending multiple second pulses to maintain the device temperature at the target temperature; the set time interval is greater than the set pulse interval; If the cooling time is longer than the set time interval, sending a first pulse and a plurality of second pulses to maintain the device temperature at the target temperature; The operating time of the IGBT device to be tested at the target temperature is measured.

6. The control method of the double pulse test device according to claim 5, characterized in that: When the device temperature is maintained at the target temperature, the method further comprises: Increasing the pulse width of the first pulse to increase the operating current of the IGBT device to be tested; Resending the first pulse and the second pulse to measure the operating performance of the IGBT device to be tested under the current operating current; Detecting whether the working performance of the IGBT device to be tested fails under the current working current; If the working performance of the IGBT device to be tested has not failed, jump to the step of increasing the pulse width of the first pulse; If the operating performance of the IGBT device under test fails at the current operating current, the limiting operating current of the IGBT device under test at the target temperature is determined according to the current operating current of the IGBT device under test.

7. The control method of the double pulse test device according to any one of claims 1 to 4, characterized in that: The double pulse test device has more than one output terminal, which is used to connect to each IGBT device under test in the same device under test. The method further includes: Determining the test requirements of each IGBT device under test based on the circuit topology of the device under test; Based on the test requirements of each IGBT device to be tested, each test interface of the double-pulse test device is controlled to output a different first pulse and second pulse.

8. A control device for a double pulse test device, characterized in that: Applicable to the double pulse test device, the double pulse test device is used to connect to the IGBT device to be tested, and the device includes: The first module is configured to send a first pulse to the IGBT device under test; the first pulse is configured to control the IGBT device under test to be turned off after being saturated and turned on; The second module is used to continuously send multiple second pulses to the IGBT device under test until the device temperature of the IGBT device under test rises to the target temperature, and measure the switching characteristics of the IGBT device under test at the target temperature; wherein the pulse width of the second pulse is smaller than the pulse width of the first pulse, and during the duration of the pulse width of the second pulse, the IGBT device under test operates in the linear region.

9. A testing system, characterized in that: include: Double pulse test set and conversion board; The dual-pulse test device is connected to the IGBT device to be tested via the conversion board; the conversion board is provided with a plurality of test interfaces respectively connected to the output terminals of the dual-pulse test device, and drive interfaces respectively connected to the IGBT devices to be tested, and each test interface is correspondingly connected to each drive interface; The double-pulse testing device is used to implement the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

Images