Press-pack IGBT Research Articles

An Alternative Junction-to-Case Thermal Resistance Test Method for High Power Press-Pack IGBTs

An Alternative Junction-to-Case Thermal Resistance Test Method for High Power Press-Pack IGBTs

Improving Short-Circuit Withstand Capability by Targeted Optimization Package for Press-Pack IGBT Module

Improving Short-Circuit Withstand Capability by Targeted Optimization Package for Press-Pack IGBT Module

Impacts of the Pressure Distribution on Dynamic Avalanche in Single Press-Pack IGBT Chip

Impacts of the Pressure Distribution on Dynamic Avalanche in Single Press-Pack IGBT Chip

Partial discharge characteristics of peek utilized in press-pack IGBT under DC voltage

Modular multilevel converters (MMCs) have been utilized in solid-state transformers (SSTs). With the increasing demand in high-voltage power module in MMC-SST, press-pack IGBTs are very promising. The poly-ether-ether-ketone (PEEK) frame is utilized in the submodules of press-pack IGBT to withstand the high voltage. The electric field simulation in this paper reveals that electric field concentrates on the surface of the PEEK frame. Thus, the surface partial discharge characteristics under direct current (DC) voltage is investigated by the developed test bench. The results show that surface partial discharge model of PEEK sample has polarity effect. Under positive and negative polarity voltage, the average discharge quantity, maximum discharge quantity and discharge repetition rate of the PEEK sample all increase with the voltage amplitude. Moreover, the front time of the surface partial discharge waveform reaches 20 ns, and its frequency spectrum is concentrated in range of 10–20 MHz.

The influence of external conditions on the physical characteristics of Press-Pack IGBTs

In order to solve the problem of unclear factors affecting the physical characteristics of Press-Pack IGBT devices, this paper explores the influence characteristics of the two main external conditions of fixture pressure and heat dissipation capacity on the physical parameters of Press-Pack IGBTs by building IGBT models with different chip structure layout considering various physical characteristics of materials. The results show that the effect of fixture pressure on the stress characteristics of the device is more obvious than the heat dissipation ability of the device, and the water-cooling heat flux has more influence on the electrical-thermal characteristics of the device. The research results provide a reference for the external conditions and structure selection of Press-Pack IGBTs.

High Interference-Resistant Magnetic Field Probe for Non-Invasive Current Distribution Monitoring in Press Pack IGBTs of HVDC Valves

High Interference-Resistant Magnetic Field Probe for Non-Invasive Current Distribution Monitoring in Press Pack IGBTs of HVDC Valves

An Improved Evaluation Method for the Short-Circuit Withstand Capability of Press-Pack IGBT Modules

An Improved Evaluation Method for the Short-Circuit Withstand Capability of Press-Pack IGBT Modules

Investigation on Saturation Voltage Increment of Multichip Press-Pack IGBTs Under Power Cycling Tests

Investigation on Saturation Voltage Increment of Multichip Press-Pack IGBTs Under Power Cycling Tests

An Improved Thermal Network Model of Press-Pack IGBT Modules Considering Contact Surface Damage

An Improved Thermal Network Model of Press-Pack IGBT Modules Considering Contact Surface Damage

A Segmented Rogowski Coils Based Noninvasive Monitoring Method of Current Imbalance in Press Pack IGBTs

A Segmented Rogowski Coils Based Noninvasive Monitoring Method of Current Imbalance in Press Pack IGBTs

Short-Circuit Capability Optimization of Press-Pack IGBT by Improving Active Edge Heat Dissipation

Press-pack insulated gate bipolar transistor (PP-IGBT) device has been widely used in VSC-HVDC converters. Research on the optimization method of short-circuit capability is crucial to improve the short-circuit robustness and reliability of PP-IGBT. Aiming at the problem of device failure due to transient overstress induced by press-pack packaging, this paper proposes a short-circuit capability optimization method of PP-IGBT that improving the active edge heat dissipation by using silver conductive adhesive (SCA). Firstly, the short-circuit capability is evaluated by experimental test, and the failure conditions and positions are obtained. Secondly, based on the finite element method simulation, the electrical-thermal-mechanical stress of PP-IGBT under short-circuit transients is analyzed and the optimization method by using SCA is proposed. Thirdly, the short-circuit capability of PP-IGBT with SCA coating is tested and verified. Lastly, the potential of SCA coating under different short-circuit voltage levels is discussed. The results indicate that the transient thermal shock at the active corner of the chip that is not in direct contact with the emitter molybdenum plate causes device failure and improving the active edge heat dissipation by SCA could be an effective approach to improve the short-circuit capability of PP-IGBT.

On the application of liquid metal cooling for electronic switching devices

Increasingly smaller and lighter power electronics converters are needed for the advancement of electrified transport. The development of high heat flux heat sinks is imperative to maintain modern converters at an operable temperature. So far, liquid metal based heat sinks have not received as much attention as other solutions, yet they provide a multitude of benefits beyond their superior thermal conductivity. Their use with compact magnetohydrodynamic pumping systems, straight-forward incorporations of active cooling techniques, elimination of water corrosion issues in power converter systems using press-pack IGBT’s and a significant increase in thermal performance in conventional pin–fin structures are demonstrated in this paper. Some additional functionalities of liquid metal systems which could be explored in the future are also highlighted.

Lifetime prediction for press pack IGBT device by considering fretting wear failure

The reliability of the Press-Pack Insulated Gate Bipolar Transistor (PP-IGBT) device is important to guarantee the safety of modular multilevel converter (MMC). The fretting wear failure is the typical failure mode of long-time operation in the PP-IGBT device. However, the traditional fretting wear lifetime model of the PP-IGBT device only considers the fretting wear failure of the IGBT chip, which is difficult to accurately predict the reliability of the PP-IGBT device. The influence of fretting wear failure of all layers on the device's lifetime is ignored. This paper proposes a lifetime model of the PP-IGBT device by considering the fretting wear failure of all layers using the fault tree method. First, a finite element (FE) model of the PP-IGBT device is established by considering the multi-physics coupling, and the contact surface roughness change of each layer is obtained by power cycling simulation. Then, based on fretting wear failure and Basquin law, the lifetime of each layer is obtained, and a fault tree method is established to build the fretting wear lifetime model of the PP-IGBT device by considering the fretting wear failure of all layers. Finally, the power cycling experiment of the PP-IGBT device is established, and the experiment results are used to verify the effectiveness of the proposed lifetime model. The results show that the relative error between the proposed lifetime model and the experimental results is nearly 5 %.

Measuring Double-Sided Thermal Resistance of Press-Pack IGBT Modules Based on Ratio of Double-Sided Heat Dissipation

Precise measurements of the double-sided thermal resistance of press-pack insulated gate bipolar transistors (PP IGBTs) are challenging because of their special packaging and operating conditions. This article presents a method for calculating the double-sided heat dissipation ratio of PP IGBT modules. An indirect measurement technique for the power consumption on both sides of the module is also proposed, in which the water temperature is measured at the inlet and outlet of the water-cooled radiators corresponding to the collector and the emitter in the working state of the module. A PP IGBT device test fixture is constructed that can apply a measurable and adjustable pressure to the device and provide electrical connections. According to the proposed test theory, a matching double-sided thermal resistance test platform is developed to test a PP IGBT module made by the State Grid Smart Grid Research Institute. The influence of pressure on the thermal conduction characteristics of the PP IGBT module is then analyzed.

Testing and Assessment on the Short-Circuit Withstand Capability of Press-Pack IGBT Considering the Unbalanced Clamping Forces

Press-pack insulated gate bipolar transistors (PP-IGBTs) modules have become the mainstream choice in high-power-density applications such as breakers. Sufficient short-circuit (SC) withstand capacity is the key to the safe operation of power electronic equipment. However, the effect of the unbalanced clamping force, which is experienced frequently in the multichip PP-IGBT, on the SC withstand capacity needs to be studied. First, an SC withstand test platform is established to calibrate the critical energy for different voltage levels. Second, the SC process and the withstand capacity for different clamping forces are investigated experimentally. Combined with the finite-element simulation results, the effect of the clamping force on the SC withstand capability is analyzed, and the weak parts are pointed out. An evaluation method of SC withstand capacity considering the effects of the voltage levels and the clamping force is proposed. Finally, the effect of the unbalanced clamping force is experimentally studied using parallel single-chip modules (PPI), and the SC withstand test of a 3300-V/200-A multichip module with unbalanced clamping force is carried out. The results show that the clamping force has little effect on the critical energy, but the module with greater clamping force has worse SC withstand capacity.

Time-Variant Reliability Optimization for Stress Balance in Press-Pack Insulated Gate Bipolar Transistors

Time-Variant Reliability Optimization for Stress Balance in Press-Pack Insulated Gate Bipolar Transistors

Time-domain and Frequency-domain Analyses of PETT Oscillation in Press Pack IGBTs

Time-domain and Frequency-domain Analyses of PETT Oscillation in Press Pack IGBTs

Current Measurement Method of Multiple Chips Using Rectangular PCB Rogowski Coils Integrated in Press Pack IGBT Device

Unbalance of transient currents of multiple chips inside press-pack insulated-gate bipolar transistor (PP IGBT) results in degrading operation and even device damage. Chip currents measurement plays an essential role to understand and solve this problem. Printed-circuit board Rogowski coil (PCB RC), as a small, noninvasive, and high bandwidth current sensor, is very suitable for this application. However, PCB RC integrated with multiple Rogowski coils (RCs) is still difficult to be applied to measure the current of multiple chips in press pack IGBT device because of the low measurement accuracy due to the large interference. In this letter, a high accuracy PCB RC with ten rectangular RCs inside PP IGBT is proposed to measure ten chip currents at the same time. Different from single RC measuring single chip current, the interference of adjacent chip currents has to be considered, and is reduced to 0.6% by optimizing the turns arrangement and lead wires of RCs. The noise of cross talk of adjacent RCs is 1.7% by decreasing the capacitance coupling between RCs. Shielding layers and grounding patter of lead wires for ten RCs are proposed to eliminate the interference of collector voltage. The experiment of transient process of ten chips verifies the effectiveness of proposed PCB RC, and measurement error is only 1.8%.

A Thermal Twin Modeling Method of Press Pack IGBT Based on Power Loss

The thermal modeling of a press pack insulated gate bipolar transistor (PP-IGBT) is crucial for device reliability estimation and operation management. However, the traditional finite element model (FEM) cannot simulate the temperature of a PP-IGBT device in real time, resulting in lifetime evaluation delays and errors. Therefore, this article proposes a thermal twin (TT) modeling method of a PP-IGBT based on power loss. First, common PP-IGBT TT modeling based on the reduced-order model (ROM) technology is introduced, and an optimized PP-IGBT TT modeling method based on power loss is proposed and compared with the common TT modeling method. Second, the electro-thermal coupling PP-IGBT FEM is determined, and the optimized PP-IGBT TT and a digital interface based on FEM simulation results are established and analyzed. Finally, the digital twin (DT) interaction system of the PP-IGBT is established, and the accuracy of the proposed TT model is verified via infrared experiments. The results reveal that the proposed PP-IGBT TT realizes the real-time and comprehensive mapping of the device temperature, and has great applicability potential in temperature monitoring and reliability evaluation.

Overview of monitoring methods of press‐pack insulated gate bipolar transistor modules under different package failure modes

Press-pack insulated gate bipolar transistor modules (PP-IGBTs) have been widely used in high-voltage and high-power-density applications, such as high-voltage direct-current (HVDC) converters, because of their advantages of low thermal resistance, double side cooling, and short-circuit failure mode. Package failure is one of the main reasons for IGBT module failure. Package condition monitoring is the key to realizing modules fault diagnosis, condition prediction, and intelligent operation and maintenance. At present, a variety of characteristic parameters, such as on voltage and junction temperature, are used in package condition monitoring. However, the characteristic parameters show different variation laws under different package degradation modes. Therefore, the relationship between package degradation modes and characteristic parameters is the key to realizing the condition monitoring, so as to improve the reliability of the power electronic system. In this paper, first, the package structure of a PP-IGBT is analyzed. Second, the mechanisms of fretting wear degradation, gate-oxide degradation, spring degradation, lid warping degradation, micro arcing degradation, short-circuit failure, and open-circuit failure are reviewed. The variation laws of characteristic parameters under each degradation and failure mode are then investigated. Finally, three difficult problems including characteristic parameter measurement, especially pressure monitoring, high-sensitivity detection, and characterization and evaluation, are discussed and analyzed.