CN114609501A - IGBT device short circuit experimental method and device - Google Patents
IGBT device short circuit experimental method and device Download PDFInfo
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- CN114609501A CN114609501A CN202210314219.3A CN202210314219A CN114609501A CN 114609501 A CN114609501 A CN 114609501A CN 202210314219 A CN202210314219 A CN 202210314219A CN 114609501 A CN114609501 A CN 114609501A
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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- G01R31/2608—Circuits therefor for testing bipolar transistors
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/26—Testing of individual semiconductor devices
- G01R31/2607—Circuits therefor
- G01R31/2608—Circuits therefor for testing bipolar transistors
- G01R31/261—Circuits therefor for testing bipolar transistors for measuring break-down voltage or punch through voltage therefor
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Abstract
The invention provides a short circuit experiment method and a short circuit experiment device for an IGBT device, wherein the device comprises the following components: the system comprises a bus capacitance energy supplementing circuit, a short circuit test main circuit, a bridge arm current generating circuit, a driving circuit and a data acquisition circuit, wherein two ends of the bus capacitance energy supplementing circuit are correspondingly connected with the positive electrode and the negative electrode of an external direct-current power supply, and the bus capacitance energy supplementing circuit is also connected with the short circuit test main circuit in parallel; the two ends of the bridge arm current generating circuit are correspondingly connected with the positive and negative poles of an external direct-current power supply, and the bridge arm current generating circuit is also connected with the short-circuit test main loop; the driving circuit is connected with the short circuit test main loop; the data acquisition circuit is respectively connected with the short circuit test main loop and the bridge arm current generation circuit. By implementing the method, the important guiding function is provided for the domestic research and development and the engineering application of the converter valve.
Description
Technical Field
The invention relates to the field of flexible direct current transmission and the field of semiconductor device testing, in particular to a short circuit experiment method and device for an IGBT device.
Background
The MMC Converter valve is core equipment of a flexible Direct-Current transmission technology, flexible Direct-Current transmission (VSC-HVDC) is a novel Direct-Current transmission system based on a Voltage Source Converter, compared with traditional Direct-Current transmission, a large amount of reactive compensation is not needed, due to the fact that a fully-controlled device is adopted, the problem of phase change failure does not exist, power can be supplied to a passive system, and active power and reactive power can be independently adjusted. The method has wide application prospect in the fields of asynchronous power grid interconnection, new energy grid connection, weak power grid power supply and the like.
The core device of the MMC flexible converter valve is an IGBT device. The reliability of the IGBT is very important for the stable operation of the MMC flexible converter valve. Transient state overcurrent condition of the flexible converter valve of MMC can make the IGBT device suffer from severe voltage and current stress, and the IGBT device is extremely easy to cause irreversible damage under the condition of short circuit, so that the stability of the flexible converter valve of MMC is influenced. The short circuit process of the direct-connection short circuit of the sub-module IGBT is severe, and the short circuit current of the sub-module IGBT can be about 10 times of that of the sub-module IGBT under the normal working condition. Therefore, the research on the stress and the failure of the transient working condition of the IGBT device of the converter valve with the sub-module IGBT direct-connection short circuit plays an important guiding role in the domestic research and development and engineering application of the converter valve.
Disclosure of Invention
Therefore, the technical problem to be solved by the invention is to overcome the defect that the stress and the failure of the transient working condition of the IGBT device of the converter valve with the direct short circuit of the sub-module IGBT are difficult to test in the prior art, so that the short circuit experiment method and the device of the IGBT device are provided.
In order to achieve the purpose, the invention provides the following technical scheme:
in a first aspect, an embodiment of the present invention provides an IGBT device short circuit experimental apparatus, including: the bridge arm current generating circuit comprises a bus capacitance energy compensating circuit, a short circuit testing main loop, a bridge arm current generating circuit, a driving circuit and a data acquisition circuit, wherein two ends of the bus capacitance energy compensating circuit are correspondingly connected with the positive and negative electrodes of an external direct current power supply, and the bus capacitance energy compensating circuit is also connected with the short circuit testing main loop in parallel; the two ends of the bridge arm current generating circuit are correspondingly connected with the positive and negative poles of an external direct-current power supply, and the bridge arm current generating circuit is also connected with the short-circuit test main loop; the driving circuit is connected with the short circuit test main loop; and the data acquisition circuit is respectively connected with the short circuit test main loop and the bridge arm current generation circuit.
Preferably, the short circuit test main loop includes: the device comprises a first device to be tested, a second device to be tested, a first diode, a second diode, an auxiliary device and a first protection device, wherein the first device to be tested is reversely connected with the first diode in parallel, and the second device to be tested is reversely connected with the second diode in parallel; the first end of the first device to be tested is connected with one end of the bus capacitor energy supplementing circuit through the first protection device, the second end of the first device to be tested is respectively connected with the first end of the second device to be tested, the first end of the auxiliary device and the bridge arm current generating circuit, and the control end of the first device to be tested is connected with the driving circuit; the control end of the second device to be tested is connected with the driving circuit, and the second end of the second device to be tested and the second end of the auxiliary device are both grounded.
Preferably, the bus capacitance energy supplementing circuit includes: the protection circuit comprises a first capacitor, a first resistor, a second resistor, a first controllable device and a second controllable device, wherein the anode of the first capacitor is respectively connected with one end of the second resistor, the first end of the first controllable device and the first end of the first protection device, and the cathode of the first capacitor is connected with the cathode of an external direct-current power supply and then grounded; the other end of the second resistor is connected with the cathode of the first capacitor through the second controllable device; and the second end of the first controllable device is connected with the anode of an external direct current power supply through the first resistor.
Preferably, the bridge arm current generating circuit includes: the bridge arm energy compensating circuit comprises a bridge arm current inductor, a load capacitor energy compensating circuit and a follow current loop, wherein one end of the bridge arm current inductor is respectively connected with the second end of the first device to be tested, the first end of the second device to be tested and the first end of the auxiliary device, and the other end of the bridge arm current inductor is connected with the load capacitor energy compensating circuit; two ends of the load capacitor energy supplementing circuit are correspondingly connected with the positive electrode and the negative electrode of an external direct current power supply; the follow current loop is connected with the bridge arm current inductor in parallel.
Preferably, the load capacitance energy compensating circuit includes: the protection circuit comprises a second capacitor, a third resistor, a fourth resistor, a third controllable device, a fourth controllable device and a second protection device, wherein the anode of the second capacitor is respectively connected with one end of the third resistor, one end of the fourth resistor and the first end of the second protection device, and the cathode of the second capacitor is connected with the cathode of an external direct-current power supply and then grounded; the second end of the second protection device is connected with the other end of the bridge arm current inductor; the other end of the fourth resistor is connected with the cathode of the second capacitor through the fourth controllable device; the other end of the third resistor is connected with the anode of an external direct current power supply through the third controllable device.
Preferably, the data acquisition circuit comprises: a first high-voltage measuring probe, a second high-voltage measuring probe, a low-voltage differential active voltage measuring probe, a low-voltage passive voltage measuring probe, a first drive current measuring device, a second drive current measuring device, a short-circuit current measuring device and a bridge arm current measuring device,
the first high-voltage measuring probe is connected to the first end of the second device to be measured; the second high-voltage measuring probe is connected to the first end of the first device to be tested; the low-voltage differential active voltage measuring probe is connected to the control end of the first device to be measured; the low-voltage passive voltage measuring probe is connected to the control end of the second device to be measured; the first driving current measuring device is arranged on a driving lug plate which is connected with the first device to be tested in the driving circuit; the second driving current measuring device is arranged on a driving lug plate which is connected with the second device to be tested in the driving circuit; the short-circuit current measuring device is arranged at the second end of the second device to be tested; the bridge arm current measuring device is arranged on a circuit of the bridge arm current generating circuit.
In a second aspect, an embodiment of the present invention provides an IGBT device short circuit experimental method, which is based on the IGBT device short circuit experimental apparatus in the first aspect of the embodiment of the present invention, and includes: establishing bus voltage of a submodule of a device to be tested; establishing bridge arm current of a submodule of a device to be tested according to preset experiment requirements, wherein the preset experiments comprise a first short circuit experiment, a second short circuit experiment and a third short circuit experiment; controlling a driving circuit to generate a pulse signal according to a preset experiment requirement, and controlling a corresponding device to be tested to be connected to a short-circuit test main loop to perform a short-circuit experiment according to the pulse signal; and acquiring experimental data acquired by the data acquisition circuit, and evaluating the reliability of the device to be tested according to the experimental data.
Preferably, when a first-type short-circuit experiment is performed, the controlling, according to the pulse signal, the corresponding device to be tested to access the short-circuit test main loop to perform the short-circuit experiment includes: bypassing the first device to be tested, and disconnecting the bridge arm current inductor; the first controllable device is conducted, and the first capacitor is charged to a first preset voltage; and triggering the second device to be tested to be conducted, wherein the second device to be tested generates a first type short circuit.
Preferably, when performing the second type of short circuit experiment, the controlling the corresponding device to be tested to access the short circuit test main loop according to the pulse signal to perform the short circuit experiment includes: disconnecting the second device to be tested; the first controllable device is conducted, and the first capacitor is charged to a second preset voltage; the third controllable device is conducted, and the second capacitor is charged to a third preset voltage; establishing bridge arm current flowing out of the submodule direction by utilizing the first capacitor and the second capacitor; and conducting a first device to be tested and an auxiliary device, wherein a second type of short circuit is generated under the first device to be tested.
Preferably, when a third type of short circuit experiment is performed, the step of controlling the corresponding device to be tested to be connected to the short circuit test main loop according to the pulse signal to perform the short circuit experiment includes: disconnecting the second device to be tested; the first controllable device is conducted, and the first capacitor is charged to a fourth preset voltage; the third controllable device is conducted, and the second capacitor is charged to a fifth preset voltage; bridge arm current flowing into the sub-module direction is established by utilizing a second capacitor; and conducting a first device to be tested and the auxiliary device, wherein the first device to be tested generates a third type short circuit.
The technical scheme of the invention has the following advantages:
the invention provides an IGBT device short circuit experimental device, which comprises: the system comprises a bus capacitance energy supplementing circuit, a short circuit test main circuit, a bridge arm current generating circuit, a driving circuit and a data acquisition circuit, wherein two ends of the bus capacitance energy supplementing circuit are correspondingly connected with the positive electrode and the negative electrode of an external direct-current power supply, and the bus capacitance energy supplementing circuit is also connected with the short circuit test main circuit in parallel; the two ends of the bridge arm current generating circuit are correspondingly connected with the positive and negative poles of an external direct-current power supply, and the bridge arm current generating circuit is also connected with the short-circuit test main loop; the driving circuit is connected with the short circuit test main loop; the data acquisition circuit is respectively connected with the short circuit test main loop and the bridge arm current generation circuit. The short-circuit experiment device of the IGBT device is used for being equivalent to a sub-module direct-connection short-circuit working condition with bridge arm current influence, a short-circuit experiment platform is provided for the IGBT device, stress and failure of the transient working condition of the IGBT device of the converter valve with the sub-module IGBT direct-connection short circuit can be researched, and an important guiding function is provided for domestic research and development and engineering application of the converter valve.
The short circuit experiment method of the IGBT device provided by the invention comprises the following steps: establishing bus voltage of a submodule of a device to be tested; establishing bridge arm current of a submodule of a device to be tested according to preset experiment requirements, wherein the preset experiments comprise a first short circuit experiment, a second short circuit experiment and a third short circuit experiment; controlling a driving circuit to generate a pulse signal according to a preset experiment requirement, and controlling a corresponding device to be tested to be connected to a short-circuit test main loop to perform a short-circuit experiment according to the pulse signal; and acquiring experimental data acquired by the data acquisition circuit, and evaluating the reliability of the device to be tested according to the experimental data. The short-circuit establishing experimental environment is provided for the IGBT device through the equivalent sub-module direct short-circuit working condition with bridge arm current influence, three types of IGBT standard short-circuit experiments can be carried out on the IGBT device of the converter valve with the sub-module IGBT direct short-circuit, and the short-circuit establishing experimental device has an important guiding function for the domestic research and development and engineering application of the converter valve.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a schematic block diagram of a specific example of an IGBT device short circuit experimental apparatus according to an embodiment of the present invention;
fig. 2 is a circuit diagram of a specific example of an IGBT device short-circuit experimental apparatus according to an embodiment of the present invention;
fig. 3 is a flowchart of a specific example of an IGBT device short-circuit experimental method in an embodiment of the present invention.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; the two elements may be directly connected or indirectly connected through an intermediate medium, or may be communicated with each other inside the two elements, or may be wirelessly connected or wired connected. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
As shown in fig. 1, an embodiment of the present invention provides an IGBT device short circuit experimental apparatus, including: the system comprises a bus capacitance energy supplementing circuit 1, a short circuit test main loop 2, a bridge arm current generating circuit 3, a driving circuit 4 and a data acquisition circuit 5, wherein two ends of the bus capacitance energy supplementing circuit 1 are correspondingly connected with the positive and negative poles of an external direct current power supply, and the bus capacitance energy supplementing circuit 1 is also connected with the short circuit test main loop 2 in parallel; the two ends of the bridge arm current generating circuit 3 are correspondingly connected with the positive and negative poles of an external direct-current power supply, and the bridge arm current generating circuit 3 is also connected with the short-circuit test main loop 2; the driving circuit 4 is connected with the short circuit test main loop 2; the data acquisition circuit 5 is respectively connected with the short circuit test main loop 2 and the bridge arm current generation circuit 3.
In a specific embodiment, the circuit structure of the IGBT device short-circuit experimental device adopts the same circuit structure as the submodule so as to be equivalent to the direct short-circuit working condition of the submodule of the MMC converter valve, so that the actual working environment of the device to be tested can be simulated under the experimental environment. Specifically, the bus voltage of the submodule is generated by matching the bus capacitance energy compensating circuit 1 with an external direct-current power supply. And generating the bridge arm current by matching the bus capacitor energy supplementing circuit 1, the bridge arm current generating circuit 3 and an external direct current power supply. Therefore, the bus voltage and the bridge arm current of the sub-module are used as the key stress in the direct short-circuit working condition of the device to be tested.
Further, based on the stress, the driving circuit 4 is used for controlling the device to be tested to be sequentially conducted, so that the short circuit of the device to be tested can be triggered, and a short circuit experiment is carried out. And then, acquiring experimental data in the short circuit experimental process by using the data acquisition circuit 5, and evaluating the stability of the device to be tested based on the experimental data.
The invention provides an IGBT device short circuit experimental device, which comprises: the system comprises a bus capacitance energy supplementing circuit, a short circuit test main circuit, a bridge arm current generating circuit, a driving circuit and a data acquisition circuit, wherein two ends of the bus capacitance energy supplementing circuit are correspondingly connected with the positive electrode and the negative electrode of an external direct-current power supply, and the bus capacitance energy supplementing circuit is also connected with the short circuit test main circuit in parallel; the two ends of the bridge arm current generating circuit are correspondingly connected with the positive and negative poles of an external direct-current power supply, and the bridge arm current generating circuit is also connected with the short-circuit test main loop; the driving circuit is connected with the short circuit test main loop; the data acquisition circuit is respectively connected with the short circuit test main loop and the bridge arm current generation circuit. The short-circuit experiment device of the IGBT device is used for being equivalent to a sub-module direct-connection short-circuit working condition with bridge arm current influence, a short-circuit experiment platform is provided for the IGBT device, stress and failure of the transient working condition of the IGBT device of the converter valve with the sub-module IGBT direct-connection short circuit can be researched, and an important guiding function is provided for domestic research and development and engineering application of the converter valve.
In one embodiment, as shown in fig. 2, the short circuit test main loop 2 includes: the device comprises a first device to be tested T1, a second device to be tested T2, a first diode D1, a second diode D2, an auxiliary device T3 and a first protection device T4, wherein the first device to be tested T1 and the first diode D1 are connected in parallel in an opposite direction, and the second device to be tested T2 and the second diode D2 are connected in parallel in an opposite direction; the first end of a first device to be tested T1 is connected with one end of a bus capacitor energy supplementing circuit 1 through a first protection device T4, the second end of the first device to be tested T1 is respectively connected with the first end of a second device to be tested T2, the first end of the auxiliary device T3 and the bridge arm current generating circuit 3, and the control end of the first device to be tested T1 is connected with the driving circuit 4; the control end of the second dut T2 is connected to the driving circuit 4, and the second end of the second dut T2 and the second end of the auxiliary device T3 are both grounded.
In a specific embodiment, the first dut T1 is an upper-tube IGBT device T1. The second device under test T2 is a lower tube IGBT device under test T2. The upper tube IGBT device T1 to be tested, the lower tube IGBT device T2 to be tested and the anti-parallel diodes D1 and D2 are connected to a short circuit test main loop through a special test seat, and the test seat is used for connecting the device to be tested and a circuit board, so that the device to be tested can be conveniently replaced.
Further, the auxiliary device T3 is an IGBT device, which has a large current turn-off capability. The auxiliary device T3 can be used for carrying out standard experiments of the first short circuit, the second short circuit and the third short circuit on the IGBT to be tested. When a short-circuit experiment is carried out, the driving circuit 4 is used for controlling the upper tube IGBT device T1 to be tested and the lower tube IGBT device T2 to be sequentially conducted, and then the upper tube IGBT device T1 to be tested and the lower tube IGBT device T2 to be short-circuited can be triggered.
In the embodiment of the present invention, the first protection device T4 is an IGBT. The upper tube is connected between the IGBT (T1) to be tested and the positive electrode of the bus capacitor (C1) to form a bus protection IGBT (T4), and when the upper tube is damaged by the IGBT to be tested and cannot be normally turned off, the bus protection IGBT can turn off short-circuit current, so that an experiment platform is protected.
In one embodiment, as shown in fig. 2, the bus capacitor energy charging circuit 1 includes: the protection circuit comprises a first capacitor C1, a first resistor R1, a second resistor R2, a first controllable device T7 and a second controllable device T8, wherein the anode of the first capacitor C1 is connected with one end of the second resistor R2, the first end of the first controllable device T7 and the first end of the first protection device T4 respectively, and the cathode of the first capacitor C1 is connected with the cathode of an external direct-current power supply and then grounded; the other end of the second resistor R2 is connected to the cathode of the first capacitor C1 through a second controllable device T8; a second terminal of the first controllable device T7 is connected to the positive terminal of the external dc power supply through a first resistor R1.
In one embodiment, the first resistor R1 and the second resistor R2 are power resistors to limit the rate at which the capacitors charge and discharge. The first controllable device T7 is a charging IGBT and the second controllable device T8 is a discharging IGBT. The control ends of the first controllable device T7 and the second controllable device T8 are connected with an external remote control device. The external remote control device controls the charging and discharging of the first capacitor C1 by controlling the on and off of the charging IGBT and the discharging IGBT.
Specifically, when the first capacitor C1 is charged, the external dc power supply is first adjusted to a desired voltage value. The external remote control then sends a pulse signal to control the first controllable device T7 to conduct. The external dc power supply charges the first capacitor C1 to the voltage required by the experiment through the diode D4, the power resistor R1, and the first controllable device T7. When discharging the first capacitor C1, the external remote control sends a pulse signal to control the second controllable device T8 to conduct. The first capacitor C1 discharges through the power resistor R2 and the second controllable device T8. In the experimental process, the charging and discharging of each capacitor are remotely controlled, so that the safety of personnel is ensured.
In one embodiment, as shown in fig. 2, the bridge arm current generating circuit 3 includes: the bridge arm current inductor L1, the load capacitor energy supplementing circuit 31 and the freewheeling circuit 32, wherein one end of the bridge arm current inductor L1 is connected with the second end of the first device to be tested T1, the first end of the second device to be tested T2 and the first end of the auxiliary device T3 respectively, and the other end of the bridge arm current inductor L1 is connected with the load capacitor energy supplementing circuit 31; two ends of the load capacitor energy compensating circuit 31 are correspondingly connected with the positive pole and the negative pole of an external direct current power supply; freewheeling circuit 32 is connected in parallel with bridge arm current inductor L1.
In one embodiment, bridge arm current inductor L1 is housed in an electromagnetic shield that generates an electromagnetic field that interferes with the control and measurement circuitry. The free-wheeling circuit 32 is connected with a free-wheeling diode D3 and a blocking IGBT T6.
In one embodiment, as shown in fig. 2, the load capacitance charging circuit 31 includes: the protection circuit comprises a second capacitor C2, a third resistor R3, a fourth resistor R4, a third controllable device T9, a fourth controllable device T10 and a second protection device T5, wherein the anode of the second capacitor C2 is connected with one end of the third resistor R3, one end of the fourth resistor R4 and the first end of the second protection device T5 respectively, and the cathode of the second capacitor C2 is connected with the cathode of an external direct-current power supply and then grounded; the second end of the second protection device T5 is connected with the other end of the bridge arm current inductor L1; the other end of the fourth resistor R4 is connected to the cathode of the second capacitor C2 through a fourth controllable device T10; the other end of the third resistor R3 is connected to the anode of the external dc power supply through a third controllable device T9.
In one embodiment, the third resistor R3 and the fourth resistor R4 are power resistors to limit the rate at which the capacitors charge and discharge. The third controllable device T9 is a charging IGBT, the fourth controllable device T10. The control ends of the third controllable device T9 and the fourth controllable device T10 are connected with an external remote control device. And the external remote control device controls the charging and discharging of the second capacitor C2 by controlling the on and off of the charging IGBT and the discharging IGBT.
Specifically, when the second capacitor C1 is charged, the external dc power supply is first adjusted to a desired voltage value. The external remote control then sends a pulse signal to control the third controllable device T9 to conduct. The external direct current power supply charges the second capacitor C2 to the voltage required by the experiment through the diode D5, the power resistor R3 and the third controllable device T9. When discharging the second capacitor C2, the external remote control sends a pulse signal to control the fourth controllable device T10 to conduct. The second capacitor C2 discharges through the power resistor R4 and the fourth controllable device T10. In the experimental process, the charging and discharging of each capacitor are remotely controlled, so that the safety of personnel is ensured.
In the embodiment of the present invention, the second protection device T5 is an IGBT. And a bridge arm current loop protection IGBT (T5) is connected between the positive electrode of the load capacitor (C2) and the bridge arm current inductor (L1), and can turn off the load current when the upper IGBT or the lower IGBT is damaged and cannot be normally turned off.
In one embodiment, the driving circuit 4 includes a driving tab, a gate resistor, and an IGBT driving board. The IGBT driving board is connected to the G pole of the upper IGBT device T1 to be tested and the G pole of the lower IGBT device T2 to be tested through driving lugs, and the driving grid resistor is connected to the circuit board through a testing seat. The driving lug plate is specially designed, mutual inductance between the driving lug plate and a short circuit loop is low, and the influence of short circuit current on driving voltage is small. The driving lug is wrapped in a metal shielding box.
In an embodiment, when the first-type short circuit experiment is performed, the IGBT to be tested is the second device under test T2, the first device under test T1 is replaced by a conducting wire, and the first device under test T1 is short-circuited. The bridge arm current inductor L1 is pulled out, thereby disconnecting the bridge arm inductor L1. The first controllable device T7 is turned on, and the first capacitor C1 is charged to a voltage required by a short-circuit test. And triggering the second device to be tested T2 to be conducted, and generating a first type short circuit at the voltage by the second device to be tested T2.
In one embodiment, when performing the second type of short circuit experiment, the IGBT under test is the first device under test T1. And pulling out the second device under test T2 and the second diode D2 which is reversely connected with the second device under test T2 in parallel, thereby disconnecting the second device under test T2. The first controllable device T7 is turned on, and the first capacitor C1 is charged to the voltage U required by the second type short circuit experimentSM. Then the third controllable device T9 is triggered to conduct by remote control, the second capacitor C2 is charged to a certain voltage value UC2. Controlling the conduction time T of the upper tube IGBT (T1) to be testedonThe bridge arm inductance L1 generates the bridge arm current to the target value Iarm＝((USM-UC2)*Ton) and/L1, establishing bridge arm current flowing out of the sub-module direction as load current, keeping the IGBT (T1) to be tested on and triggering the auxiliary device T3 to be switched on by the load current, and enabling the first device T1 to generate second type short circuit.
In one embodiment, when performing the third type of short circuit experiment, the IGBT under test is the first device under test T1 and its anti-parallel diode D1. And pulling out the second device under test T2 and the second diode D2 which is reversely connected with the second device under test T2 in parallel, thereby disconnecting the second device under test T2. The voltage of an adjustable direct current power source1 is set, a first controllable device T7 is triggered to be conducted in a remote control mode, a first capacitor C1 is charged, and a sub-module bus voltage U is establishedSM. Remotely triggering the third controllable device T9 to conduct and charging the second capacitor C2 to a certain voltage value UC2. Then controlling the conduction time T of the auxiliary device T3onThe bridge arm inductance L1 generates the bridge arm current to the target value Iarm＝(UC2*Ton) and/L1, establishing bridge arm current flowing into the direction of the sub-modules as load current, and keeping the IGBT (T1) to be tested to be conducted. However, the load current flows through the first diode D1 instead of the first device under test T1, triggering the auxiliary device T3 to conduct, and causing the third type short circuit to occur in the first device under test T1.
In an embodiment, the data acquisition circuit 5 comprises: the bridge arm current measuring device comprises a first high-voltage measuring probe V2, a second high-voltage measuring probe V1, a low-voltage differential active voltage measuring probe V3, a low-voltage passive voltage measuring probe V4, a first driving current measuring device I3, a second driving current measuring device I4, a short-circuit current measuring device I1 and a bridge arm current measuring device I2.
In one embodiment, as shown in FIG. 2, a first high voltage measurement probe V2 is connected to a first end of a second DUT T2; the second high-voltage measuring probe V1 is connected to the first end of the first device to be tested T1; the low-voltage differential active voltage measurement probe V3 is connected to the control end of the first device to be tested T1; the low-voltage passive voltage measuring probe V4 is connected to the control end of the second device to be tested T2; the first driving current measuring device I3 is arranged on a driving lug connected with the first device to be tested T1 in the driving circuit 4; the second driving current measuring device I4 is arranged on a driving lug which is connected with a second device to be tested T2 in the driving circuit 4; the short-circuit current measuring device I1 is arranged at the second end of the second device to be tested T2; the bridge arm current measuring device I2 is installed in a line installed in the bridge arm current generating circuit 3.
In the embodiment of the invention, the V of the upper tube IGBT to be tested is measured by the first high-voltage measuring probe V2CEAnd the short-circuit current waveform I measured by the short-circuit current measuring device I1CWhether the tested IGBT of the upper tube is failed or not and the failure reason can be judged. Likewise, the V of the lower tube IGBT to be tested is measured by the second high-voltage measuring probe V1CEAnd the short-circuit current waveform I measured by the short-circuit current measuring device I1CWhether the IGBT to be tested of the lower tube is failed or not and the failure reason can be judged.
Further, by repeating the experiment under different stress parameters, the short circuit tolerance limits (maximum voltage, maximum current, tolerance duration, safe working area, etc.) of the device can be summarized. Through the measurement (V3, V4, I3, I4) to the upper tube IGBT and the lower tube IGBT gate drive that is surveyed, can analyze the regulation and control effect of grid signal to the short circuit to formulate more reasonable drive regulation and control strategy, strengthen driven short-circuit protection ability.
In the embodiment of the invention, the first drive current measuring device I3 and the second drive current measuring device I4 are wrapped in a metal shielding box, and the shielding box is used for shielding the interference of an external magnetic field on the first drive current measuring device I3 and the second drive current measuring device I4.
Compared with the prior art, the invention has the following beneficial effects:
1. the invention provides a short-circuit experimental device for an IGBT device, which can be equivalent to a direct short-circuit working condition of a submodule with bridge arm current influence.
2. The invention provides a short-circuit experimental device for an IGBT device, which can be used for carrying out three types of standard short-circuit experiments on the IGBT device.
3. The invention provides a short circuit experiment device for an IGBT device, wherein the bus voltage of a sub-module of a platform and the current and the direction of a bridge arm can be adjusted according to experiment requirements.
4. The invention provides a short-circuit experimental device for an IGBT device, which has a continuous short-circuit protection mechanism, and can protect the IGBT to turn off short-circuit current when the IGBT to be tested fails and has continuous short circuit in the experiment.
The embodiment of the invention also provides an IGBT device short circuit experimental method, which is based on the IGBT device short circuit experimental device shown in FIG. 2, and as shown in FIG. 3, the IGBT device short circuit experimental method comprises the following steps:
step S1: and establishing the bus voltage of the submodule of the device to be tested.
In one embodiment, the sub-module bus voltage is set by an external adjustable dc power supply. The voltage of an adjustable direct current power source1 is set, a first controllable device T7 is triggered to be conducted in a remote control mode, a first capacitor C1 is charged, and a sub-module bus voltage U is establishedSM。
Step S2: and establishing bridge arm current of the sub-module of the device to be tested according to the preset experiment requirements, wherein the preset experiment comprises a first short circuit experiment, a second short circuit experiment and a third short circuit experiment.
In a specific embodiment, the bridge arm current flowing into the submodule and the bridge arm current flowing out of the submodule are respectively established according to different experimental types.
In the embodiment of the invention, the bridge arm current flowing into the sub-module is established, the voltage of the adjustable direct current power source1 needs to be set, the third controllable device T9 is triggered to be conducted in a remote control mode, and the second capacitor C2 is charged to a certain voltage value UC2. Then controlling the conduction time T of the lower tube IGBT (T2) to be testedonThe bridge arm inductance L1 generates the bridge arm current to the target value Iarm＝(UC2*Ton)/L1。
When bridge arm current flowing out of the submodule is established, adjustable direct current power source1 voltage needs to be set, the first controllable device T7 is triggered to be conducted in a remote control mode, the first capacitor C1 is charged to establish submodule bus voltage USM. Then the third controllable device T9 is triggered to conduct by remote control, the second capacitor C2 is charged to a certain voltage value UC2. Controlling the conduction time T of the upper tube IGBT (T1) to be testedonThe bridge arm inductance L1 generates the bridge arm current to the target value Iarm＝((USM-UC2)*Ton)/L1。
In the embodiment of the present invention, the magnitude of the bridge arm current can adjust the voltage U of the second capacitor C2 according to the above formulaC2Or the conduction time Ton of the upper tube IGBT (T1) to be tested is adjusted.
Step S3: and controlling the driving circuit to generate a pulse signal according to the preset experiment requirement, and controlling the corresponding device to be tested to be connected to the short-circuit test main loop according to the pulse signal to perform a short-circuit experiment.
In a specific embodiment, when performing the first-type short-circuit experiment, controlling the corresponding device to be tested to access the short-circuit test main loop according to the pulse signal to perform the short-circuit experiment, includes the following steps:
step S310: bypassing the first device to be tested T1 and turning off the leg current inductor L1.
Step S311: the first controllable device T7 is turned on to charge the first capacitor C1 to the first preset voltage.
Step S312: and triggering the second device to be tested T2 to be conducted, and generating a first type short circuit on the second device to be tested T2.
In the embodiment of the invention, during the first-type short-circuit experiment, the tested IGBT is the second device to be tested T2, the position of the first device to be tested T1 is replaced by a conducting wire, and the position of the first device to be tested T1 is in short circuit. The bridge arm current inductor L1 is pulled out, thereby disconnecting the bridge arm inductor L1. The first controllable device T7 is turned on, and the first capacitor C1 is charged to a voltage required by a short-circuit test. And triggering the second device to be tested T2 to be conducted, and generating a first type short circuit at the voltage by the second device to be tested T2. In the embodiment of the invention, the first preset voltage is set according to the requirement of the first-class short circuit experiment.
Further, when a second type of short circuit experiment is performed, the corresponding device to be tested is controlled to be connected to the short circuit test main loop according to the pulse signal to perform the short circuit experiment, and the method comprises the following steps:
step S320: the second device under test T2 is turned off.
Step S321: the first controllable device T7 is turned on to charge the first capacitor C1 to the second predetermined voltage.
Step S322: the third controllable device T9 is turned on to charge the second capacitor C2 to the third predetermined voltage.
Step S323: the bridge arm current flowing out of the direction of the submodule is established by using a first capacitor C1 and a second capacitor C2.
Step S324: the first device under test T1 and the auxiliary device T3 are turned on, and the first device under test T1 is short-circuited of the second type.
Specifically, when the second type short circuit experiment is performed, the IGBT under test is the first device under test T1. And pulling out the second device under test T2 and the second diode D2 which is reversely connected with the second device under test T2 in parallel, thereby disconnecting the second device under test T2. The first controllable device T7 is turned on, and the first capacitor C1 is charged to the voltage U required by the second type short circuit experimentSM. Then the third controllable device T9 is triggered to conduct by remote control, the second capacitor C2 is charged to a certain voltage value UC2. Controlling the conduction time T of the upper tube IGBT (T1) to be testedonThe bridge arm inductance L1 generates the bridge arm current to the target value Iarm＝((USM-UC2)*Ton) and/L1, establishing bridge arm current flowing out of the sub-module direction as load current, keeping the IGBT (T1) to be tested on and triggering the auxiliary device T3 to be switched on by the load current, and enabling the first device T1 to generate second type short circuit. In the embodiment of the invention, the second preset voltage and the third preset voltage are set according to the requirements of the second type of short circuit experiment.
Further, when a third type of short circuit experiment is performed, the corresponding device to be tested is controlled to be connected to the short circuit test main loop according to the pulse signal to perform the short circuit experiment, and the method comprises the following steps:
step S330: the second device under test T2 is turned off.
Step S331: the first controllable device T7 is turned on to charge the first capacitor C1 to the fourth preset voltage.
Step S332: the third controllable device T9 is turned on to charge the second capacitor C2 to the fifth predetermined voltage.
Step S333: the bridge leg current in the direction of the submodule is established by means of a second capacitor C2.
Step S334: the first device under test T1 and the auxiliary device T3 are turned on, and the first device under test T1 is short-circuited in the third class.
Specifically, when the third type of short circuit experiment is performed, the IGBT under test is the first device under test T1 and its anti-parallel diode D1. And pulling out the second device under test T2 and the second diode D2 reversely connected in parallel with the second device under test T2, thereby disconnecting the second device under test T2. The voltage of an adjustable direct current power source1 is set, a first controllable device T7 is triggered to be conducted in a remote control mode, a first capacitor C1 is charged, and a sub-module bus voltage U is establishedSM. Remotely triggering the third controllable device T9 to conduct and charging the second capacitor C2 to a certain voltage value UC2. Then controlling the conduction time T of the auxiliary device T3onThe bridge arm inductance L1 generates the bridge arm current to the target value Iarm＝(UC2*Ton) and/L1, establishing bridge arm current flowing into the direction of the sub-modules as load current, and keeping the IGBT (T1) to be tested to be conducted. However, the load current flows through the first diode D1 instead of the first device under test T1, triggering the auxiliary device T3 to conduct, and causing the third type short circuit to occur in the first device under test T1. In the embodiment of the invention, the fourth preset voltage isAnd five preset voltages are set according to the requirements of the third type of short circuit experiment.
Step S4: and acquiring experimental data acquired by the data acquisition circuit, and evaluating the reliability of the device to be tested according to the experimental data.
In one embodiment, the V of the upper tube measured IGBT is measured by a first high voltage measurement probe V2CEAnd the short-circuit current waveform I measured by the short-circuit current measuring device I1CWhether the upper tube detected IGBT fails or not and the failure reason can be judged. Similarly, the V of the lower IGBT to be tested is measured by the second high-voltage measuring probe V1CEAnd the short-circuit current waveform I measured by the short-circuit current measuring device I1CWhether the IGBT to be tested of the lower tube is failed or not and the failure reason can be judged.
Further, by repeating the experiment under different stress parameters, the short circuit tolerance limits (maximum voltage, maximum current, tolerance duration, safe working area, etc.) of the device can be summarized. Through the measurement (V3, V4, I3, I4) to the upper tube IGBT and the lower tube IGBT gate drive that is surveyed, can analyze the regulation and control effect of grid signal to the short circuit to formulate more reasonable drive regulation and control strategy, strengthen driven short-circuit protection ability.
The short circuit experiment method of the IGBT device provided by the invention comprises the following steps: establishing bus voltage of a submodule of a device to be tested; establishing bridge arm current of a submodule of a device to be tested according to preset experiment requirements, wherein the preset experiments comprise a first short circuit experiment, a second short circuit experiment and a third short circuit experiment; controlling a driving circuit to generate a pulse signal according to a preset experiment requirement, and controlling a corresponding device to be tested to be connected to a short circuit test main loop to perform a short circuit experiment according to the pulse signal; and acquiring experimental data acquired by the data acquisition circuit, and evaluating the reliability of the device to be tested according to the experimental data. The short-circuit establishing experimental environment is provided for the IGBT device through the equivalent sub-module direct short-circuit working condition with bridge arm current influence, three types of IGBT standard short-circuit experiments can be carried out on the IGBT device of the converter valve with the sub-module IGBT direct short-circuit, and the short-circuit establishing experimental device has an important guiding function for the domestic research and development and engineering application of the converter valve.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the spirit or scope of the invention.
Claims (10)
1. The utility model provides a short circuit experimental apparatus of IGBT device which characterized in that includes: a bus capacitor energy compensating circuit, a short circuit test main circuit, a bridge arm current generating circuit, a driving circuit and a data acquisition circuit, wherein,
two ends of the bus capacitor energy supplementing circuit are correspondingly connected with the positive electrode and the negative electrode of an external direct-current power supply, and the bus capacitor energy supplementing circuit is also connected with the short circuit test main loop in parallel;
the two ends of the bridge arm current generating circuit are correspondingly connected with the positive and negative poles of an external direct-current power supply, and the bridge arm current generating circuit is also connected with the short-circuit test main loop;
the driving circuit is connected with the short circuit test main loop;
and the data acquisition circuit is respectively connected with the short circuit test main loop and the bridge arm current generation circuit.
2. The short-circuit experimental device for the IGBT device according to claim 1, wherein the short-circuit test main loop comprises: a first device under test, a second device under test, a first diode, a second diode, an auxiliary device and a first protection device,
the first device to be tested is connected with the first diode in an inverse parallel mode, and the second device to be tested is connected with the second diode in an inverse parallel mode;
the first end of the first device to be tested is connected with one end of the bus capacitor energy supplementing circuit through the first protection device, the second end of the first device to be tested is respectively connected with the first end of the second device to be tested, the first end of the auxiliary device and the bridge arm current generating circuit, and the control end of the first device to be tested is connected with the driving circuit;
the control end of the second device to be tested is connected with the driving circuit, and the second end of the second device to be tested and the second end of the auxiliary device are both grounded.
3. The IGBT device short circuit experimental apparatus of claim 2, characterized in that, the bus capacitance can make-up circuit includes: a first capacitor, a first resistor, a second resistor, a first controllable device, and a second controllable device,
the anode of the first capacitor is connected with one end of the second resistor, the first end of the first controllable device and the first end of the first protection device respectively, and the cathode of the first capacitor is grounded after being connected with the cathode of an external direct-current power supply;
the other end of the second resistor is connected with the cathode of the first capacitor through the second controllable device;
and the second end of the first controllable device is connected with the anode of an external direct current power supply through the first resistor.
4. The IGBT device short circuit experimental apparatus of claim 2, wherein the bridge arm current generating circuit comprises: bridge arm current inductor, load capacitance energy compensating circuit and follow current loop, wherein,
one end of the bridge arm current inductor is respectively connected with the second end of the first device to be tested, the first end of the second device to be tested and the first end of the auxiliary device, and the other end of the bridge arm current inductor is connected with the load capacitor energy supplementing circuit;
two ends of the load capacitor energy supplementing circuit are correspondingly connected with the positive electrode and the negative electrode of an external direct current power supply;
the follow current loop is connected with the bridge arm current inductor in parallel.
5. The IGBT device short circuit experimental apparatus of claim 4, characterized in that, the load capacitance can make-up circuit includes: a second capacitor, a third resistor, a fourth resistor, a third controllable device, a fourth controllable device, and a second protection device,
the anode of the second capacitor is connected with one end of the third resistor, one end of the fourth resistor and the first end of the second protection device respectively, and the cathode of the second capacitor is grounded after being connected with the cathode of an external direct-current power supply;
the second end of the second protection device is connected with the other end of the bridge arm current inductor;
the other end of the fourth resistor is connected with the cathode of the second capacitor through the fourth controllable device;
the other end of the third resistor is connected with the anode of an external direct current power supply through the third controllable device.
6. The IGBT device short circuit experimental apparatus of claim 2, characterized in that, the data acquisition circuit includes: a first high-voltage measuring probe, a second high-voltage measuring probe, a low-voltage differential active voltage measuring probe, a low-voltage passive voltage measuring probe, a first drive current measuring device, a second drive current measuring device, a short-circuit current measuring device and a bridge arm current measuring device,
the first high-voltage measuring probe is connected to the first end of the second device to be measured; the second high-voltage measuring probe is connected to the first end of the first device to be tested; the low-voltage differential active voltage measuring probe is connected to the control end of the first device to be measured; the low-voltage passive voltage measuring probe is connected to the control end of the second device to be measured; the first driving current measuring device is arranged on a driving lug plate which is connected with the first device to be tested in the driving circuit; the second driving current measuring device is arranged on a driving lug plate which is connected with the second device to be tested in the driving circuit; the short-circuit current measuring device is arranged at the second end of the second device to be tested; the bridge arm current measuring device is arranged on a circuit of the bridge arm current generating circuit.
7. An IGBT device short circuit experimental method, based on the IGBT device short circuit experimental device of any one of claims 1-6, the IGBT device short circuit experimental method comprises:
establishing bus voltage of a submodule of a device to be tested;
establishing bridge arm current of a submodule of a device to be tested according to preset experiment requirements, wherein the preset experiments comprise a first short circuit experiment, a second short circuit experiment and a third short circuit experiment;
controlling a driving circuit to generate a pulse signal according to a preset experiment requirement, and controlling a corresponding device to be tested to be connected to a short-circuit test main loop to perform a short-circuit experiment according to the pulse signal;
and acquiring experimental data acquired by the data acquisition circuit, and evaluating the reliability of the device to be tested according to the experimental data.
8. The short-circuit experimental method for the IGBT device according to claim 7, wherein when a first type of short-circuit experiment is performed, the step of controlling the corresponding device to be tested to be connected to the short-circuit test main loop according to the pulse signal to perform the short-circuit experiment comprises the steps of:
bypassing the first device to be tested, and disconnecting the bridge arm current inductor;
the first controllable device is conducted, and the first capacitor is charged to a first preset voltage;
and triggering the second device to be tested to be conducted, wherein the second device to be tested generates a first type short circuit.
9. The short-circuit experimental method of the IGBT device according to claim 7, wherein when a second type of short-circuit experiment is performed, the step of controlling the corresponding device to be tested to access the short-circuit test main loop according to the pulse signal to perform the short-circuit experiment comprises the steps of:
disconnecting the second device to be tested;
the first controllable device is conducted, and the first capacitor is charged to a second preset voltage;
the third controllable device is conducted, and the second capacitor is charged to a third preset voltage;
establishing bridge arm current flowing out of the submodule direction by using the first capacitor and the second capacitor;
and conducting a first device to be tested and an auxiliary device, wherein a second type of short circuit is generated under the first device to be tested.
10. The short-circuit experimental method of the IGBT device according to claim 7, wherein when a third type of short-circuit experiment is performed, the step of controlling the corresponding device to be tested to access the short-circuit test main loop according to the pulse signal to perform the short-circuit experiment comprises the steps of:
disconnecting the second device to be tested;
the first controllable device is conducted, and the first capacitor is charged to a fourth preset voltage;
the third controllable device is conducted, and the second capacitor is charged to a fifth preset voltage;
bridge arm current flowing into the sub-module direction is established by utilizing a second capacitor;
and conducting a first device to be tested and the auxiliary device, wherein the first device to be tested generates a third type short circuit.
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| CN116953464A (en) * | 2023-07-31 | 2023-10-27 | 荣信汇科电气股份有限公司 | All-condition short circuit test method and device for IGBT power module |
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| CN116953464A (en) * | 2023-07-31 | 2023-10-27 | 荣信汇科电气股份有限公司 | All-condition short circuit test method and device for IGBT power module |
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