IGBT device current distribution sensing method and device based on short coil array

Abstract

The invention provides an IGBT device current distribution sensing method and device based on a short coil array, and relates to the technical field of electrical engineering. The method comprises the following steps that short coil arrays in the X-axis direction and the Y-axis direction are arranged on the surface of a to-be-tested crimping type IGBT device, and the short coil arrays comprise short coils arranged at preset intervals; connecting the two ends of each short coil with an integrator circuit; measuring induced electromotive force generated at two ends of each short coil; the measured induced electromotive force is converted into current distribution change near the short coils through integrator circuits connected with the two ends of each short coil, and the current distribution state of a chip in the to-be-measured crimping type IGBT device is analyzed. According to the method, the sensitivity of measuring the internal current distribution of the IGBT device is improved, the more accurate and detailed internal current distribution condition of the device is obtained, monitoring errors are reduced, safety early warning can be carried out in time, effective intervention measures can be taken, and the aging state of the device can be evaluated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrical engineering, and in particular to an IGBT device current distribution sensing method and device based on a short coil array. BACKGROUND

[0002] As a key technology for building a new power system, the core equipment of high-voltage and high-power crimping type IGBT (Insulated Gate Bipolar Transistor) devices is the most critical weak link in the HVDC converter valve. By monitoring the state parameter drift in the aging process of the crimping type IGBT device in real time, the health of the crimping type IGBT device can be effectively evaluated through state monitoring technology, providing an important basis for fault early warning and preventive maintenance. With the upgrading of modern equipment management system and the accelerated promotion of digital power grid construction, real-time sensing and intelligent operation and maintenance of equipment operating state have become the core content of the digital transformation of power equipment, and are also an important technical support for realizing intelligent operation and maintenance of power grids.

[0003] At present, the state monitoring of crimping type IGBT devices mainly focuses on device voltage, current and saturation voltage drop parameters. However, for crimping type IGBT devices, the internal parallel chip current uniformity often deteriorates significantly during the failure and aging process. This uneven current phenomenon can cause local chip thermal stress concentration, and then trigger a vicious cycle of thermal-electric coupling, accelerating the chip aging process. Understanding the internal current distribution of crimping type IGBT devices is very important for determining whether the internal heating of crimping type IGBT devices is uniform and whether there is a potential short-circuit failure risk. Therefore, the current distribution characteristics of parallel chips can not only intuitively reflect the health status of crimping type IGBT devices, but also serve as a key feature parameter for evaluating the aging degree of crimping type IGBT devices, which is of great significance for realizing precise state monitoring of crimping type IGBT devices.

[0004] In related technologies, the internal current distribution sensing method of crimping type IGBT devices has the defect that the specific chip current distribution cannot be obtained. This method can only obtain the current eccentricity trend. In addition, the sensing sensitivity of the current distribution at the center of the crimping type IGBT device is not high, which will cause a large error in the state sensing and safety warning of the crimping type IGBT device during operation, which is not conducive to timely taking effective intervention measures, and cannot obtain more accurate and detailed current distribution, which is difficult to meet the spatial constraint requirements of high-density power electronic equipment. SUMMARY

[0005] The present application aims at the problems existing in the prior art, and provides an IGBT device current distribution sensing method and device based on a short coil array, which can place a strip-shaped short coil array on an X-axis direction and a Y-axis direction of a surface of a compression type IGBT device, improve the sensitivity of internal current distribution measurement of the compression type IGBT device, improve the accuracy of state sensing of the compression type IGBT device in an operation process, obtain more accurate and detailed internal current distribution of the compression type IGBT device, realize accurate state monitoring of the compression type IGBT device, reduce monitoring errors, can timely perform safety early warning, and timely take effective intervention measures, the current of each chip in the compression type IGBT device can be calculated through measurement and inversion calculation of the short coil array, so that the aging state of each chip in the compression type IGBT device can be evaluated according to the real-time distribution of the internal current of the compression type IGBT device.

[0006] To achieve the above object, the technical scheme adopted by the present application is as follows:

[0007] In a first aspect, the present application provides an IGBT device current distribution sensing method based on a short coil array, which comprises:

[0008] An X-axis direction and a Y-axis direction short coil array is arranged on the surface of a to-be-measured compression type IGBT device, wherein the short coil array comprises a plurality of short coils arranged at a preset interval in the X-axis direction and the Y-axis direction;

[0009] Both ends of each short coil are connected to an integrator circuit;

[0010] The induced electromotive force generated at both ends of each short coil is measured;

[0011] The induced electromotive force generated at both ends of each short coil is converted into the current distribution change near the short coil through the integrator circuit connected to both ends of each short coil;

[0012] Based on the current distribution change near the short coil, the current distribution state of the chip inside the to-be-measured compression type IGBT device is analyzed to obtain an analysis result.

[0013] In some embodiments, the induced electromotive force generated at both ends of each short coil is converted into the current distribution change near the short coil through the integrator circuit connected to both ends of each short coil, which comprises:

[0014] The induced electromotive force generated at both ends of each short coil in the X-axis direction is converted into the current distribution change of the short coil at different positions in the X-axis direction through the integrator circuit connected to both ends of each short coil;

[0015] The integrator circuit connected to both ends of each short coil converts the measured induced electromotive force generated at both ends of each short coil in the Y-axis direction into a current distribution change of the short coil at different positions in the Y-axis direction.

[0016] In some embodiments, based on the current distribution change near the short coil, the current distribution state of the internal chip of the crimp type IGBT device under test is analyzed to obtain an analysis result, including:

[0017] When the output current of the short coil at different positions in the X-axis direction is symmetrical along the X-axis, or when the output current of the short coil at different positions in the Y-axis direction is symmetrical along the Y-axis, it is determined that the current of the internal chip of the crimp type IGBT device under test is in a uniform current distribution state.

[0018] In some embodiments, based on the current distribution change near the short coil, the current distribution state of the internal chip of the crimp type IGBT device under test is analyzed to obtain an analysis result, including:

[0019] When the output current of the short coil at different positions in the X-axis direction is asymmetrical along the X-axis, or when the output current of the short coil at different positions in the Y-axis direction is asymmetrical along the Y-axis, it is determined that the current distribution of the internal chip of the crimp type IGBT device under test is not uniform.

[0020] In some embodiments, the method further comprises:

[0021] When the output current of the short coil at a certain position in the X-axis direction or the Y-axis direction is greater than or equal to a pre-set output current threshold, it is determined that the current of the chip corresponding to the position of the short coil inside the crimp type IGBT device under test is large, and it is determined that the output current at the position of the symmetrical coil symmetrical to the short coil at the certain position in the X-axis direction or the Y-axis direction is small.

[0022] When the output current of the short coil at a certain position in the X-axis direction or the Y-axis direction is less than a pre-set output current threshold, it is determined that the current of the chip corresponding to the position of the short coil inside the crimp type IGBT device under test is small, and it is determined that the output current at the position of the symmetrical coil symmetrical to the short coil at the certain position in the X-axis direction or the Y-axis direction is large.

[0023] In a second aspect, the present application also provides an IGBT device current distribution sensing device based on a short coil array, the device comprising:

[0024] a short coil array arranged on the surface of a crimp type IGBT device under test in the X-axis direction and the Y-axis direction, wherein the short coil array comprises a plurality of short coils arranged at a pre-set interval in the X-axis direction and the Y-axis direction;

[0025] an integrator circuit connected to both ends of each of the short coils;

[0026] a measurement unit configured to measure an induced electromotive force generated at both ends of each of the short coils;

[0027] a conversion unit configured to convert the measured induced electromotive force generated at both ends of each of the short coils into a current distribution change of the short coil in the vicinity of the short coil through the integrator circuit connected to both ends of each of the short coils;

[0028] a current distribution measurement unit configured to analyze a current distribution state of the internal chip of the press-pack IGBT device under test based on the current distribution change of the short coil in the vicinity of the short coil, and obtain an analysis result.

[0029] In some embodiments, the conversion unit includes:

[0030] an X-axis conversion module configured to convert the measured induced electromotive force generated at both ends of each of the short coils in the X-axis direction into a current distribution change of the short coil at different positions in the X-axis direction through the integrator circuit connected to both ends of each of the short coils;

[0031] a Y-axis conversion module configured to convert the measured induced electromotive force generated at both ends of each of the short coils in the Y-axis direction into a current distribution change of the short coil at different positions in the Y-axis direction through the integrator circuit connected to both ends of each of the short coils.

[0032] In some embodiments, the current distribution measurement unit includes:

[0033] a uniform current distribution determination module configured to determine that the current of the internal chip of the press-pack IGBT device under test is in a uniform current distribution state when the output currents of the short coils at different positions in the X-axis direction are symmetrical along the X-axis, and when the output currents of the short coils at different positions in the Y-axis direction are symmetrical along the Y-axis.

[0034] In some embodiments, the current distribution measurement unit includes:

[0035] a non-uniform current distribution determination module configured to determine that the current distribution of the internal chip of the press-pack IGBT device under test is not uniform when the output currents of the short coils at different positions in the X-axis direction are asymmetrical along the X-axis, or when the output currents of the short coils at different positions in the Y-axis direction are asymmetrical along the Y-axis.

[0036] In some embodiments, the apparatus further includes:

[0037] The first analysis unit is configured to determine that the current of the chip corresponding to the position of the short coil in the to-be-tested press-type IGBT device is large when the output current of the short coil at a certain position in the X-axis direction or the Y-axis direction is greater than or equal to a preset output current threshold, and determine that the output current at the position of the symmetrical coil symmetrical to the short coil at a certain position in the X-axis direction or the Y-axis direction is small.

[0038] The second analysis unit is configured to determine that the current of the chip corresponding to the position of the short coil in the to-be-tested press-type IGBT device is small when the output current of the short coil at a certain position in the X-axis direction or the Y-axis direction is less than a preset output current threshold, and determine that the output current at the position of the symmetrical coil symmetrical to the short coil at a certain position in the X-axis direction or the Y-axis direction is large.

[0039] Compared with the related art, the present application has the following beneficial effects:

[0040] The present application provides an IGBT device current distribution sensing method and device based on a short coil array. The method can place a strip-shaped short coil array on the surface of a to-be-tested press-type IGBT device in the X-axis direction and the Y-axis direction, and connect an integrator circuit at both ends of each short coil in the short coil array, convert the induced electromotive force generated at both ends of each short coil into a change in the current distribution near the short coil, and analyze the current distribution state of the internal chip of the to-be-tested press-type IGBT device. The sensitivity of the internal current distribution measurement of the to-be-tested press-type IGBT device is improved, the accuracy of the state sensing of the to-be-tested press-type IGBT device during operation is improved, a more accurate and detailed internal current distribution of the to-be-tested press-type IGBT device is obtained, accurate state monitoring of the to-be-tested press-type IGBT device is realized, monitoring errors are reduced, safety warnings can be given in time, and effective intervention measures can be taken in time. The current of each chip in the to-be-tested press-type IGBT device can be calculated by measurement and inversion of the short coil array, so that the aging state of each chip in the to-be-tested press-type IGBT device can be evaluated according to the real-time distribution of the internal current of the to-be-tested press-type IGBT device. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 A flowchart of an IGBT device current distribution sensing method based on a short coil array is provided for the embodiments of the present disclosure.

[0042] Figure 2 A global structure schematic diagram of the short coil array arranged on the surface of the to-be-tested press-type IGBT device 1 in the X-axis direction and the Y-axis direction is provided for the embodiments of the present disclosure.

[0043] Figure 3A top view of a short coil array on an X-Y plane provided by an embodiment of the present disclosure;

[0044] Figure 4 A side view of a short coil array on an X-Z plane provided by an embodiment of the present disclosure;

[0045] Figure 5 A structure schematic diagram of connecting an integrator circuit at both ends of a short coil provided by an embodiment of the present disclosure;

[0046] Figure 6 A structure schematic diagram of an IGBT device current distribution sensing device based on a short coil array provided by an embodiment of the present disclosure;

[0047] Figure 7 A structure schematic diagram of another IGBT device current distribution sensing device based on a short coil array provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0048] It is worth noting that the methods used in the present application are conventional methods unless otherwise specified; the raw materials and devices used are conventional commercially available products unless otherwise specified, and their sources are not specifically limited.

[0049] Reference Figure 1 , Figure 1 A flowchart of an IGBT device current distribution sensing method based on a short coil array provided by an embodiment of the present disclosure, the present disclosure provides an IGBT device current distribution sensing method based on a short coil array, comprising the following steps:

[0050] S101, arranging a short coil array in the X-axis direction and the Y-axis direction on the surface of a to-be-measured crimp-type IGBT device 1, wherein the short coil array comprises a plurality of short coils 2 arranged at a preset interval in the X-axis direction and the Y-axis direction.

[0051] S102, connecting an integrator circuit at both ends of each short coil 2.

[0052] S103, measuring the induced electromotive force generated at both ends of each short coil 2.

[0053] S104, converting the measured induced electromotive force generated at both ends of each short coil 2 into a current distribution change near the short coil 2 through the integrator circuit connected at both ends of each short coil 2.

[0054] S105, analyzing the current distribution state of the internal chip of the to-be-measured crimp-type IGBT device 1 based on the current distribution change near the short coil 2, to obtain an analysis result.

[0055] The embodiment of the present disclosure provides an IGBT device current distribution sensing method based on a short coil array. The method can place a strip-shaped short coil array in the X-axis direction and the Y-axis direction on the surface of a to-be-measured press-type IGBT device 1, and connect an integrator circuit at both ends of each short coil 2 in the short coil array, so as to convert the induced electromotive force generated at both ends of each short coil 2 into a change in the current distribution near the short coil 2, and analyze the current distribution state of the chip inside the to-be-measured press-type IGBT device 1. The sensitivity of the internal current distribution measurement of the to-be-measured press-type IGBT device 1 is improved, and the precision of the state sensing of the to-be-measured press-type IGBT device 1 during operation is improved. More accurate and detailed internal current distribution of the to-be-measured press-type IGBT device 1 is obtained, accurate state monitoring of the to-be-measured press-type IGBT device 1 is realized, monitoring errors are reduced, safety warnings can be given in time, and effective intervention measures can be taken in time. The current of each chip inside the to-be-measured press-type IGBT device 1 can be calculated through the measurement and inversion of the short coil array, so that the aging state of each chip inside the to-be-measured press-type IGBT device 1 can be evaluated according to the real-time distribution of the internal current of the to-be-measured press-type IGBT device 1.

[0056] Referring to Figure 2 , Figure 2 A global structure schematic diagram of the short coil array in the X-axis direction and the Y-axis direction on the surface of the to-be-measured press-type IGBT device 1 is provided for the embodiment of the present disclosure. The short coil array provided by the embodiment of the present disclosure can be placed randomly relative to the placement position of the to-be-measured press-type IGBT device 1. The number of short coils 2 in the short coil array can be set according to the actual business needs of the user, and has nothing to do with the distribution of the chips inside the to-be-measured press-type IGBT device 1. The following embodiment of the present disclosure takes the placement angle in the X-axis direction as an example for illustration.

[0057] Referring to Figure 3 and Figure 4 , Figure 3 A top view of the short coil array on the X-Y plane is provided for the embodiment of the present disclosure, Figure 4The side view of the short coil array in the X-Z plane provided by the embodiment of the present disclosure is provided, and the embodiment of the present disclosure is arranged in a row (for example, 6) of short coils 2 in the X-axis direction according to a preset interval, and 6 rows of short coils 2 are uniformly arranged in the vertical direction of the X-axis (that is, the Y-axis direction), a total of 36 short coils 2 are arranged, and a short coil array in the X-axis direction is formed. The arrangement of each short coil 2 can measure the induced electromotive force generated at both ends of the short coil 2 when the current component in the X-axis direction changes, so as to obtain the current component change in the X-axis direction. Since the X-axis vertical direction (Y-axis direction) also includes six rows of short coils 2, the current distribution change at different positions in the Y-axis direction can still be located. In this way, accurate positioning of the chip current distribution inside the to-be-measured press-pack IGBT device 1 can be realized, and when a single chip current of the to-be-measured press-pack IGBT device 1 is too large, the chip position can be located according to the inversion calculation of the short coil 2 measurement result, and safety warning measures are taken in time to avoid large-scale fault transmission.

[0058] It should be noted that the user can set the number, distribution position and distribution interval of the short coil 2 according to the actual business demand, and the embodiment of the present disclosure does not limit this.

[0059] Referring to Figure 5 , Figure 5 The structure schematic diagram of the integrator circuit connected at both ends of the short coil provided by the embodiment of the present disclosure is provided, and in some embodiments, the measured induced electromotive force generated at both ends of each short coil 2 is converted into the current distribution change near the short coil 2 through the integrator circuit connected at both ends of each short coil 2, including:

[0060] The measured induced electromotive force generated at both ends of each short coil 2 in the X-axis direction is converted into the current distribution change of the short coil 2 at different positions in the X-axis direction through the integrator circuit connected at both ends of each short coil 2.

[0061] The measured induced electromotive force generated at both ends of each short coil 2 in the Y-axis direction is converted into the current distribution change of the short coil 2 at different positions in the Y-axis direction through the integrator circuit connected at both ends of each short coil 2.

[0062] The short coil 2 of the embodiment of the present disclosure is a strip-shaped short coil, the center of the short coil 2 is without a core, the two ends of the short coil 2 are connected with the integrator circuit, and the measured induced electromotive force at both ends of the short coil 2 can be converted into the current distribution near the short coil 2 through the integrator circuit.

[0063] The embodiment of the present disclosure connects each short coil 2 with an external circuit integrator circuit, and the current change near each short coil 2 can be obtained through the induced voltage at both ends of each short coil 2. The operation of the to-be-tested press-pack IGBT device 1 is not affected during the measurement process, and real-time monitoring of the current can be achieved. The aging process of the to-be-tested press-pack IGBT device 1 can be effectively detected, and the aging law of the to-be-tested press-pack IGBT device 1 can be obtained, which is helpful for the state perception of the to-be-tested press-pack IGBT device 1.

[0064] In some embodiments, based on the current distribution change near the short coil 2, the current distribution state of the chip inside the to-be-tested press-pack IGBT device 1 is analyzed, and an analysis result is obtained, including:

[0065] When the output current of the short coil 2 at different positions in the X-axis direction is symmetrical along the X-axis, and when the output current of the short coil 2 at different positions in the Y-axis direction is symmetrical along the Y-axis, it is determined that the current of the chip inside the to-be-tested press-pack IGBT device 1 is in a uniform current distribution state.

[0066] In some embodiments, based on the current distribution change near the short coil 2, the current distribution state of the chip inside the to-be-tested press-pack IGBT device 1 is analyzed, and an analysis result is obtained, including:

[0067] When the output current of the short coil 2 at different positions in the X-axis direction is asymmetrical along the X-axis, or when the output current of the short coil 2 at different positions in the Y-axis direction is asymmetrical along the Y-axis, it is determined that the current distribution of the chip inside the to-be-tested press-pack IGBT device 1 is not uniform.

[0068] In the embodiment of the present disclosure, if the current of the chip inside the to-be-tested press-pack IGBT device 1 is uniform, the current distribution output by the integrator circuit from the induced electromotive force measured at both ends of the 36 short coils 2 arranged on the surface of the to-be-tested press-pack IGBT device 1 is symmetrical about the X-axis and the Y-axis. If the current distribution of the chip inside the to-be-tested press-pack IGBT device 1 is not uniform, the current near the position of the short coil 2 with a large induced electromotive force will be correspondingly large, and the current near the position of the symmetrical coil symmetrical with the short coil 2 will be correspondingly small. By arranging all the short coil arrays on the upper surface of the to-be-tested press-pack IGBT device 1 for measurement, the current change of the specific chip of the to-be-tested press-pack IGBT device 1 can be accurately positioned.

[0069] In some embodiments, the method further comprises:

[0070] When the output current of the short coil 2 at a certain position in the X-axis direction or the Y-axis direction is greater than or equal to a preset output current threshold, it is determined that the current of the chip corresponding to the position of the short coil 2 in the to-be-tested press-pack IGBT device 1 is too large, and it is determined that the output current at the position of the symmetrical coil symmetrical to the short coil 2 at the certain position in the X-axis direction or the Y-axis direction is too small;

[0071] When the output current of the short coil 2 at a certain position in the X-axis direction or the Y-axis direction is less than a preset output current threshold, it is determined that the current of the chip corresponding to the position of the short coil 2 in the to-be-tested press-pack IGBT device 1 is too small, and it is determined that the output current at the position of the symmetrical coil symmetrical to the short coil 2 at the certain position in the X-axis direction or the Y-axis direction is too large.

[0072] The embodiment of the present disclosure can deduce the current distribution of the chip near the short coil through the induced voltage (induced electromotive force) of each short coil, accurately locate the change of the current of each chip, and perceive the current state of the chip in the to-be-tested press-pack IGBT device, so as to reduce the device aging caused by the failure of the to-be-tested press-pack IGBT device due to external force. By arranging the short coil array on the upper surface of the to-be-tested press-pack IGBT device, the measurement sensitivity when the current distribution in the central region of the to-be-tested press-pack IGBT device changes can be effectively improved.

[0073] In the embodiment of the present disclosure, the short coil array is arranged on the upper surface of the to-be-tested press-pack IGBT device in a very close position, the arrangement direction of the short coils in the short coil array can be adjusted arbitrarily, the height of the short coil array is very small, and the thickness of the entire short coil array is very thin, so that the structure is compact in the actual measurement process.

[0074] The present patent can accurately obtain the internal current distribution state of the press-pack IGBT device in the flexible direct current converter valve according to the structural characteristics and spatial position relationship of the press-pack IGBT device, analyze and summarize the aging law of the press-pack IGBT device, and thus provide an effective basis for state evaluation of the press-pack IGBT device in the running process, and provide an effective measurement means for preventing device failure and improving device operating life in the next step.

[0075] Referring to Figure 6 , Figure 6 A structure schematic diagram of an IGBT device current distribution perception device based on a short coil array is provided in the embodiment of the present disclosure, and the embodiment of the present disclosure further provides an IGBT device current distribution perception device based on a short coil array, which comprises:

[0076] a short coil array 61 arranged on the surface of the to-be-measured press-pack IGBT device in the X-axis direction and the Y-axis direction, wherein the short coil array includes a plurality of short coils arranged at preset intervals in the X-axis direction and the Y-axis direction;

[0077] an integrator circuit 62 arranged at both ends of each short coil;

[0078] a measurement unit 63 configured to measure an induced electromotive force generated at both ends of each short coil;

[0079] a conversion unit 64 configured to convert the measured induced electromotive force generated at both ends of each short coil into a current distribution change near the short coil through the integrator circuit connected at both ends of each short coil;

[0080] a current distribution measurement unit 65 configured to analyze a current distribution state of a chip inside the to-be-measured press-pack IGBT device based on the current distribution change near the short coil, and obtain an analysis result.

[0081] Referring to Figure 7 , Figure 7 Another structure schematic diagram of an IGBT device current distribution sensing device based on a short coil array provided by the embodiment of the present disclosure is provided, and in some embodiments, the conversion unit 64 includes:

[0082] an X-axis direction conversion module 641 configured to convert the measured induced electromotive force generated at both ends of each short coil in the X-axis direction into a current distribution change of the short coil at different positions in the X-axis direction through the integrator circuit connected at both ends of each short coil;

[0083] a Y-axis direction conversion module 642 configured to convert the measured induced electromotive force generated at both ends of each short coil in the Y-axis direction into a current distribution change of the short coil at different positions in the Y-axis direction through the integrator circuit connected at both ends of each short coil.

[0084] In some embodiments, the current distribution measurement unit 65 includes:

[0085] a uniform current distribution determination module configured to determine that the current of the chip inside the to-be-measured press-pack IGBT device is in a uniform current distribution state when the output currents of the short coils at different positions in the X-axis direction are symmetrical along the X-axis, and when the output currents of the short coils at different positions in the Y-axis direction are symmetrical along the Y-axis.

[0086] In some embodiments, the current distribution measurement unit 65 includes:

[0087] The uneven current distribution determination module is configured to determine that the current distribution of the internal chip of the to-be-tested crimping type IGBT device is uneven when the output current of the short coil at different positions in the X-axis direction is asymmetric along the X-axis, or when the output current of the short coil at different positions in the Y-axis direction is asymmetric along the Y-axis.

[0088] In some embodiments, the device further comprises:

[0089] The first analysis unit is configured to determine that the current of the chip corresponding to the position of the short coil in the to-be-tested crimping type IGBT device is large when the output current of the short coil at a certain position in the X-axis direction or the Y-axis direction is greater than or equal to a preset output current threshold, and determine that the output current at the position of the symmetric coil symmetric to the short coil at the certain position in the X-axis direction or the Y-axis direction is small.

[0090] The second analysis unit is configured to determine that the current of the chip corresponding to the position of the short coil in the to-be-tested crimping type IGBT device is small when the output current of the short coil at a certain position in the X-axis direction or the Y-axis direction is less than a preset output current threshold, and determine that the output current at the position of the symmetric coil symmetric to the short coil at the certain position in the X-axis direction or the Y-axis direction is large.

[0091] Finally, it should be noted that the above content is only used to illustrate the technical solutions of the present application, and is not a limitation on the protection scope of the present application. Simple modifications or equivalent replacements of the technical solutions of the present application made by those skilled in the art do not deviate from the essence and scope of the technical solutions of the present application.

Claims

1. An IGBT device current distribution sensing method based on a short coil array is characterized by: The method comprises: Arrange a short coil array in the X-axis and Y-axis directions on the surface of the press-fit IGBT device to be tested, wherein the short coil array includes a plurality of short coils arranged in the X-axis and Y-axis directions at preset intervals; connecting both ends of each short coil to an integrator circuit; measuring the induced electromotive force generated at both ends of each short coil; The integrator circuit connected to both ends of each short coil converts the measured induced electromotive force generated at both ends of each short coil into a change in current distribution near the short coil; Based on the current distribution change near the short coil, the current distribution state of the internal chip of the press-fit IGBT device to be tested is analyzed to obtain an analysis result.

2. The IGBT device current distribution sensing method based on a short coil array according to claim 1, characterized in that: The integrator circuit connected to both ends of each short coil converts the measured induced electromotive force generated at both ends of each short coil into a current distribution change near the short coil, including: The integrator circuit connected to both ends of each short coil converts the measured induced electromotive force generated at both ends of each short coil in the X-axis direction into current distribution changes of the short coil at different positions in the X-axis direction; The integrator circuit connected to both ends of each short coil converts the measured induced electromotive force generated at both ends of each short coil in the Y-axis direction into the current distribution change of the short coil at different positions in the Y-axis direction.

3. The IGBT device current distribution sensing method based on a short coil array according to claim 2, characterized in that: Based on the current distribution change near the short coil, the current distribution state of the chip inside the press-fit IGBT device to be tested is analyzed to obtain analysis results, including: When the output current of the short coil at different positions on the X-axis is symmetrical along the X-axis, and when the output current of the short coil at different positions on the Y-axis is symmetrical along the Y-axis, it is determined that the current of the internal chip of the press-fit IGBT device to be tested is in a current-equalizing distribution state.

4. The IGBT device current distribution sensing method based on a short coil array according to claim 2, characterized in that: Based on the current distribution change near the short coil, the current distribution state of the chip inside the press-fit IGBT device to be tested is analyzed to obtain analysis results, including: When the output current of the short coils at different positions on the X-axis is asymmetric along the X-axis, or when the output current of the short coils at different positions on the Y-axis is asymmetric along the Y-axis, it is determined that the current distribution of the internal chip of the press-fit IGBT device to be tested is uneven.

5. The IGBT device current distribution sensing method based on a short coil array according to claim 4, characterized in that: The method further comprises: When the output current of the short coil at a certain position in the X-axis or Y-axis direction is greater than or equal to a preset output current threshold, it is determined that the current of the chip corresponding to the position of the short coil inside the press-fit IGBT device to be tested is too large, and it is determined that the output current of the position of the symmetrical coil symmetrical to the short coil at a certain position in the X-axis or Y-axis direction is too small; When the output current of the short coil at a certain position in the X-axis or Y-axis direction is less than a preset output current threshold, it is determined that the current of the chip corresponding to the position of the short coil inside the press-fit IGBT device to be tested is too small, and it is determined that the output current of the symmetrical coil symmetrical to the short coil at a certain position in the X-axis or Y-axis direction is too large.

6. An IGBT device current distribution sensing device based on a short coil array, characterized in that: The device comprises: A short coil array is arranged on the surface of the press-fit IGBT device to be tested in the X-axis and Y-axis directions, wherein the short coil array includes a plurality of short coils arranged at preset intervals in the X-axis and Y-axis directions; an integrator circuit, provided at both ends of each of the short coils; a measuring unit configured to measure the induced electromotive force generated at both ends of each of the short coils; a conversion unit configured to convert the measured induced electromotive force generated at both ends of each short coil into a change in current distribution near the short coil via the integrator circuit connected to both ends of each short coil; The current distribution measurement unit is configured to analyze the current distribution state of the internal chip of the press-fit IGBT device to be tested based on the current distribution change near the short coil to obtain an analysis result.

7. The IGBT device current distribution sensing device based on a short coil array according to claim 6, characterized in that: The conversion unit includes: An X-axis conversion module is configured to convert the measured induced electromotive force generated at both ends of each short coil in the X-axis direction into current distribution changes of the short coil at different positions in the X-axis direction through the integrator circuit connected to both ends of each short coil; The Y-axis conversion module is configured to convert the measured induced electromotive force generated at both ends of each short coil in the Y-axis into current distribution changes of the short coils at different positions in the Y-axis through the integrator circuit connected to both ends of each short coil.

8. The IGBT device current distribution sensing device based on a short coil array according to claim 7, characterized in that: The current distribution measurement unit includes: The current distribution determination module is configured to determine that the current of the internal chip of the press-fit IGBT device to be tested is in a current distribution state when the output current of the short coil at different positions on the X-axis is symmetrical along the X-axis, and when the output current of the short coil at different positions on the Y-axis is symmetrical along the Y-axis.

9. The IGBT device current distribution sensing device based on a short coil array according to claim 7, characterized in that: The current distribution measurement unit includes: The uneven current distribution determination module is configured to determine that the current distribution of the internal chip of the press-fit IGBT device to be tested is uneven when the output current of the short coil at different positions on the X-axis is asymmetric along the X-axis, or when the output current of the short coil at different positions on the Y-axis is asymmetric along the Y-axis.

10. The IGBT device current distribution sensing device based on a short coil array according to claim 9, characterized in that: The device further comprises: The first analysis unit is configured to, when the output current of the short coil at a certain position in the X-axis or Y-axis direction is greater than or equal to a preset output current threshold, determine that the current of a chip corresponding to the position of the short coil in the tested press-fit IGBT device is too high, and determine that the output current of a symmetrical coil symmetrical to the short coil at a certain position in the X-axis or Y-axis direction is too low; The second analysis unit is configured to determine that the current of the chip corresponding to the position of the short coil inside the press-fit IGBT device to be tested is too small when the output current of the short coil at a certain position in the X-axis or Y-axis is less than a preset output current threshold, and to determine that the output current of the position of the symmetrical coil symmetrical to the short coil at a certain position in the X-axis or Y-axis is too large.

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