Insulated Gate Bipolar Transistor Modules Research Articles

Degradation state analysis of the IGBT module based on apparent junction temperature

The multi-chip parallel insulated gate bipolar transistor (IGBT) is the core device in large-capacity power electronic equipment, but its operational reliability is of considerable concern to industry. The application of IGBT online degradation state analysis technology can be beneficial to the improvement of system reliability. The failure mechanism of IGBT devices is discussed in this paper, and a technique for analyzing the degradation state of IGBT based on apparent junction temperature is proposed. First, the distortion consistency of the voltage rise time in various failures is discussed, and the junction temperature dependence of the voltage rise time is then demonstrated. Subsequently, an apparent junction temperature model based on the voltage rise time is established (the fitting accuracy is as high as 94.3%). From the high-frequency model in the switching process of the device, an online extraction technology of key parameters (e.g., voltage rise time) is developed. Finally, an experimental platform for IGBT degradation state estimation is established, and the feasibility of IGBT degradation state estimation based on apparent junction temperature is proved, especially the degradation of bonding-wire and the gate-oxide-layer. The experimental results show that the proposed IGBT degradation state estimation technique based on apparent junction temperature is a reliable online estimation method with non-contact, high accuracy, and comprehensiveness.

Enhanced marine predators algorithm optimized support vector machine for IGBT switching power loss estimation

As the use of renewable energy generation continues to grow, improving power conversion efficiency has become an urgent task. This study aims to propose a high-precision power module loss estimation method, with a focus on predicting the switching losses of insulated gate bipolar transistor (IGBT) modules, which is crucial for the reliability assessment of IGBT modules. The main objective of this study is to establish a high-precision predictive model for IGBT module switching losses to enhance the reliability and efficiency of these devices. Firstly, a dynamic characteristic test platform was established to acquire relevant data for in-depth analysis of IGBT behavior. Secondly, given the excellent performance of support vector machine (SVM) in handling both strong and small-sized datasets, SVM was chosen as the foundational model for high-precision switching loss estimation. Subsequently, an enhanced marine predatory algorithm (EMPA), known for its superior convergence precision and speed, was introduced to optimize the random parameters of SVM. Finally, a method based on the optimized EMPA-SVM was constructed for predicting IGBT switching power losses. The proposed approach was validated using dynamic characteristic test data. And it indicated that the predictive model achieved the value of R 2 exceeding 99.8% for switching losses. Additionally, the mean absolute error and root mean square error metrics of EMPA-SVM model outperformed other models. Therefore, the research results unambiguously demonstrate the significant benefits of accurately predicting IGBT switching losses in enhancing device performance.

Bond wire lift-off detection by gate voltage waveform in IGBT turn-off process enhanced by digital gate control

This paper presents a new detection method of bond wire lift-off in Insulated Gate Bipolar Transistor (IGBT) power module. The bond wire lift-off is a major failure mode in power cycle degradation of the IGBT module, and many monitoring methods have been proposed and demonstrated for safety operation of power electronics systems in the previous works. In this study, we focus on the gate voltage waveform as an indicator to detect wire-lift for a simple and straightforward detection method. Due to the increase in parasitic inductance caused by bond wire lift-off, the turn-off switching waveform becomes modulated. The digital gate control (DGC) was employed to control the switching behavior to obtain precision for low-noise and high-performance. Furthermore, the DGC 2-step vector control (2-sVC) can enhance the sensitivity of bond wire lift-off failure detection by gate voltage waveform change. As feature quantities, the gate voltage spike peak, its amplitude and the timing shift were measured at various operating conditions. The DGC obtained larger feature quantities compared with conventional gate control. In particular, high-current conditions were found to be more favorable for achieving high sensitivity due to the high die/dt. From these results, the DGC is effective to achieve both the high sensitivity to detect bond wire lift-off by gate voltage waveform and maintaining the best switching performance.

Multi-physics coupling analysis of high-power IGBT module bonding wires fault considering stray inductance of main circuit

The insulated gate bipolar transistor (IGBT) module is subjected to unbalanced electric-thermal stress for a long time due to its own turn-on and turn-off, the fluctuation of processing power and the change of external operating environment, resulting in fatigue failure. And there is a strong coupling effect between its electrical, temperature and mechanical properties. At the same time, the fatigue failure of IGBT module is also the result of multi-physical field coupling. This paper reveals the influence mechanism of main circuit stray inductance on the electric-thermal-stress coupling characteristics of high power IGBT module bonding wires fault in the context of mine-used inverter application. First, the inverter main circuit topology model considering stray inductance is constructed, and the loss value of the power chip is obtained based on extracting the busbar stray inductance and establishing the IGBT module behavior model, and the validity of the results is verified. Secondly, the package structure model of IGBT module is established and the failure analysis boundary conditions are determined, and then the joint circuit-finite element method is used to reveal the operation behavior characteristics of IGBT module under the combined action of multi-physical fields. Finally, the influence of main circuit stray inductance on the multi-physical field coupling characteristics of IGBT module and its change law are compared and analyzed under the bonding wires fault condition to study the causes of fatigue failure of IGBT module.

A Junction Temperature Monitoring Method for IGBT Modules Based on Turn-Off Voltage With Convolutional Neural Networks

Junction temperature monitoring (JTM) is essential for reliability evaluation and health management for insulated-gate bipolar transistor (IGBT) modules, and thus is extensively focused on in power electronics converters. However, many JTM methods for IGBT modules are criticized for providing inaccurate junction temperature information with strong load current dependence. To address this, a JTM method based on the turn-off voltage (TOV) and convolutional neural networks (CNN) is proposed in this paper. In this method, the TOV is used as the junction temperature indicator, and the characterization behavior of the TOV during turn-off transient process is thoroughly analyzed. Then, the parameter dependence of the TOV is investigated. Considering the proposed JTM method may be subject to the issue of load current dependence and show an undesirable performance, the CNN is adopted to maintain the accuracy of junction temperature prediction due to its excellent global and local feature recognition capability. With this regards, the proposed JTM method enables to provide accurate junction temperature information under different conditions. Finally, the double-pulse tests and experimental tests are carried out to validate the effectiveness of the proposed JTM method.

A Novel Temperature Sensitive Electrical Parameter of IGBT Modules Without Involvement of Operating Parameters

The junction temperature estimation of the insulated gate bipolar transistor (IGBT) module is crucial for reliability assessment and health management of converters. However, most of the existing methods need to measure the collector-emitter voltage and collector current for the IGBT junction temperature estimation, which increases the cost and complexity of the monitoring and calibration process. In this article, a novel junction temperature monitoring method for IGBT modules without involving operating condition calibration based on the pre-overshoot of gate voltage is proposed. The gate pre-overshoot is influenced by the internal gate resistor, which has a linear relationship with the IGBT junction temperature. Besides, the gate pre-overshoot is only temperature dependent, while not affected by the collector-emitter voltage and collector current. Therefore, the gate pre-overshoot is a promising temperature-sensitive electrical parameter (TSEP). Because the collector-emitter voltage and collector current are not involved, the gate pre-overshoot-based method for junction temperature has the advantages of a simple signal monitoring structure, a simple calculation process, and a simple calibration process.

Research Progress in Failure Mechanism and Health State Evaluation Index System of Welded IGBT Power Modules

As the performance requirements of insulated gate bipolar transistors (IGBTs) in various fields of power electronic systems are increasing, the IGBT power module package structure, aging mechanism analysis, and selection of health state characteristic parameters are of great significance to ensure the normal operation of power systems. At present, research on the aging failure of welded IGBT modules is relatively comprehensive and can be divided into chip aging failure and package aging failure according to their failure parts. However, there is some research on the relationship between aging failure and the characteristic quantity of power modules, but no definite system has been formed. Therefore, in this paper, the packaging structure of the solder-type IGBT modules and the aging mechanism caused by different aging reasons were summarized. Moreover, the health status monitoring of solder-type IGBT modules from the junction temperature, bonding line, solder layer, and package insulation aging health status monitoring and its quantitative assessment research progress was analyzed in detail. Also, the health state evaluation index system of the solder-type IGBT modules was completed on the basis of voltage, current, thermal, insulation parameters, and other characteristic quantities. Finally, based on the analysis of domestic and international research problems, the development trend and direction of the condition monitoring technology of solder-type IGBT modules is foreseen. The research on condition monitoring for welded IGBT module technology has a certain significance.

Thermal Performance Optimization of Integrated Microchannel Cooling Plate for IGBT Power Module.

In high-integration electronic components, the insulated-gate bipolar transistor (IGBT) power module has a high working temperature, which requires reasonable thermal analysis and a cooling process to improve the reliability of the IGBT module. This paper presents an investigation into the heat dissipation of the integrated microchannel cooling plate in the silicon carbide IGBT power module and reports the impact of the BL series micropump on the efficiency of the cooling plate. The IGBT power module was first simplified as an equivalent-mass block with a mass of 62.64 g, a volume of 15.27 cm3, a density of 4.10 g/cm3, and a specific heat capacity of 512.53 J/(kg·K), through an equivalent method. Then, the thermal performance of the microchannel cooling plate with a main channel and a secondary channel was analyzed and the design of experiment (DOE) method was used to provide three factors and three levels of orthogonal simulation experiments. The three factors included microchannel width, number of secondary inlets, and inlet diameter. The results show that the microchannel cooling plate significantly reduces the temperature of IGBT chips and, as the microchannel width, number of secondary inlets, and inlet diameter increase, the junction temperature of chips gradually decreases. The optimal structure of the cooling plate is a microchannel width of 0.58 mm, 13 secondary inlets, and an inlet diameter of 3.8 mm, and the chip-junction temperature of this structure is decreased from 677 °C to 77.7 °C. In addition, the BL series micropump was connected to the inlet of the cooling plate and the thermal performance of the microchannel cooling plate with a micropump was analyzed. The micropump increases the frictional resistance of fluid flow, resulting in an increase in chip-junction temperature to 110 °C. This work demonstrates the impact of micropumps on the heat dissipation of cooling plates and provides a foundation for the design of cooling plates for IGBT power modules.

Performance Evaluation and Optimization of Series Flow Channel Water-Cooled Plate for IGBT Modules

The stability in the operation of insulated gate bipolar transistor (IGBT) modules plays a crucial role in wind power generation. It is essential to improve the thermal performance of the heat sink of IGBT modules in wind power converters and reduce the power consumption of liquid cooling systems, in order to optimize the heat dissipation of IGBT modules in wind power converters. In this paper, a simulation model of the liquid-cooled heat sink of the IGBT module is established and the performance of three different series flow channel structures is compared by computational fluid dynamics (CFD). Moreover, based on the orthogonal test design, the three factors (channel width, channel height, and cold plate wall thickness) affecting the performance of the water-cooled plate were ranked and optimized. The results show that the water-cooled plate with double-helical-type flow channel structure has the best comprehensive performance. In addition, for the double-helical-type structure, the optimal combination of channel structure parameters about channel width, channel height, and cold plate wall thickness is obtained. After optimization, the maximum IGBT temperature, thermal resistance, and pressure drop of the cold plate are reduced by 3.13%, 5.78%, and 18.87%, respectively, compared with the double-S structure in parameter case one. The proposed methods and results are expected to provide theoretical guidance for the thermal management of IGBT modules in wind power converters.

Analysis and Measurement of the Surge and Gate-Noise Voltages in a 1.7-kV IGBT Module With the Effect of Reverse-Recovery Current

This paper reveals the effect of the reverse-recovery current of a PIN diode on the surge and gate-noise voltage of an insulated-gate bipolar transistor (IGBT) in an inverter. Theoretical analysis reveals that the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$di/dt$</tex-math></inline-formula> of the reverse-recovery current, the switching speed of the IGBT and parasitic inductances affect the gate-noise voltage unlike a Schottky barrier diode (SBD) because resonance does not occur due to junction capacitances. The analysis also indicates that the surge voltage may not occur when the dc voltage is increased even though a large amount of surge voltage occurs in a low dc voltage region. A 1-kV testing setup was designed and constructed using a 1.7-kV 260-A IGBT module, which confirms the validity of the theoretical analysis.

Effect of Solder Layer Void Damage on the Temperature of IGBT Modules.

Solder layer void is one of the main failure causes of power semiconductor devices, which will seriously affect the reliability of the devices. In this study, a 3D model of IGBT (Insulated Gate Bipolar Transistor) packaging was built by DesignModeler. Based on ANSYS Workbench, the influence of void size, location, solder layer type, and thickness on the temperature distribution of the IGBT module was simulated. The results show that the larger the void radius, the higher the temperature of the IGBT module. The closer the void is to the center of the solder layer, the higher the temperature of the module. The void on the top corner of the solder layer had the greatest impact on the junction temperature of the IGBT module, and the shape of the void is also one of the factors that affect the temperature of the module. The denser the void distribution, the higher the temperature of the module. The temperature of the IGBT module was reduced from 62.656 °C to 59.697 °C by using nanosilver solder paste, and the overall heat dissipation performance of the module was improved by 5%. The temperature of the module increased linearly with the increase in solder layer thickness, and the temperature increased by 0.8 °C for every 0.025 mm increase in solder layer thickness. The simulation results have a guiding significance for improving the thermal stability of IGBT modules.

Enhancement of turn-off gate voltage waveform change by digital gate control for bond wire lift-off detection in IGBT module

The bond wire lift-off is the one of main failures for insulated gate bipolar transistors (IGBT) power modules. The wire lift-off increases parasitic inductance LeE in the module and the gate voltage Vge waveform is modulated by LeE·dIe/dt. Therefore, the Vge waveform has the potential for an indicator of condition monitoring. The Digital gate control (DGC) can control switching behavior precisely for low-loss and low-noise switching. It is also effective for sensitivity enhancement of Vge waveform changed by the wire lift-off. This paper reports how the DGC 2-step vector control (2-sVC) can improve the wire lift-off failure detection sensitivity by Vge waveform. The experiment results showed that the Vge spike was generated by LeE·dIe/dt at the turn-off switching and the spike generation timing depended on the wire number. The DGC obtained the larger timing-shift Δtwire and the amplitude ΔVge-surge than those at the conventional gate control. In addition, the best vector condition improved the trade-off between turn-off loss and collector voltage overshoot compared with the conventional gate control. From these results, the DGC is effective to enhance the sensitivity of bond wire lift-off detection by Vge waveform maintaining the best switching performance.

Effect of Si segregation at grain boundaries on the mechanical behaviours of ageing Al metallization layer in insulated gate bipolar transistor module

ABSTRACT In this study, the evolution of the Si atom distribution within an Al metallization layer in an insulated gate bipolar transistor (IGBT) module during power cycling is studied experimentally through electron backscatter diffraction (EBSD) observations, X-ray diffraction (XRD) measurements, and scanning electron microscopy (SEM) characterization. Molecular dynamics (MD) simulations are applied to study the effects of Si segregation on the mechanical properties of the Al metallization layer. The results show that Si segregation toward the Al grain boundaries occurs as the number of power cycles increases, and this behaviour strongly influences the recrystallization, texture, grain size and mechanical performance of the Al metallization layer.

A direct bonding copper degradation monitoring method for insulated gate bipolar transistor modules: Boundary‐dependent thermal network combined with feedback control

AbstractThe direct bonding copper (DBC) substrates of insulated gate bipolar transistor (IGBT) modules degrade inevitably under cycling thermo‐mechanical stress, causing potential threat to the reliability of IGBT modules. However, little attention has been paid to monitoring their degradation. This paper proposes a DBC degradation monitoring method for IGBT modules, which combines boundary‐dependent thermal network and feedback control. A thermal network is employed to describe the internal material degradation of IGBT modules and can be extracted from a finite‐element method model. The boundary conditions including power losses and DBC degradation are considered, enabling the thermal network suitable for various working conditions and different DBC degradation conditions of IGBT modules. The DBC degradation is characterised by its equivalent thermal conductivities measured in the thermal cycling ageing experiments. On the basis of the boundary‐dependent thermal network, feedback control is applied to monitor DBC degradation by regulating boundary‐dependent thermal impedances. Finally, the proposed model is verified from the effectiveness and accuracy of DBC degradation monitoring and junction temperature calculation. This method casts new light on thermal network modelling and could provide a feasible method for the monitoring of DBC degradation.

A thermal network model considering thermal coupling effect and TIM degradation in IGBT modules

Thermal interface materials (TIMs), as important materials for heat dissipation of insulated gate bipolar transistor (IGBT) modules, degrade under long-term thermal cycling, resulting in elevated junction temperatures and threatening the safe operation of IGBT modules. In consideration of the thermal coupling effect in IGBT modules, this paper proposes a three-dimensional thermal network model characterizing the TIM degradation. An IGBT module with the TIM is adopted to establish the finite element method (FEM) model, in which the TIM layer is divided into regular areas. The thermal network is established by simulating the heat transfer paths. The thermal impedance in each path is extracted according to the heat flow through its area considering the TIM degradation. Thereby, the impact of thermal coupling and TIM degradation on junction temperature of IGBT modules could be characterized. Furthermore, the proposed thermal network is verified by simulation from calculation accuracy of junction temperature and TIM temperature.

Dynamic IGBT Three-Dimensional Thermal Network Model Considering Base Solder Degradation and Thermal Coupling Between IGBT Chips

With the development of power electronic technology, the thermal characteristics of high-power insulated gate bipolar transistor (IGBT) module are vital information for thermal management of power electronic equipment, reliability analysis, and thermal design of power electronic system. However, the present commonly used lumped thermal network model based on thermal resistance and heat capacity still has some limitations in accurately predicting the junction temperature of IGBT modules, significantly once considering the degradation of base solder in high-power IGBT modules. In this paper, the thermal behavior of high-power IGBT chips under different base solder degradation is studied by the finite element method (FEM). The results show that the degradation of the base solder has effects on the thermal impedance between the junction and the case, which should be fastidiously thought about within the thermal network model modeling. As a result, a dynamic three-dimensional thermal network model that takes into account the thermal interaction between IGBT chips, as well as the degradation of the base solder, is proposed in this paper. The proposed thermal network model can estimate the junction temperature of a high-power IGBT module correctly and fast based on the real degradation of the base solder. Finally, finite element simulation and experimental findings are used to validate the proposed dynamic three-dimensional thermal network model. The results show that the dynamic three-dimensional thermal network model has comparable accuracy to finite element simulation and test results. At the same time, the dynamic three-dimensional thermal network model responds faster than the finite element simulation.

IGBT Thermal Model-Based Predictive Energy Management Strategy for Plug-In Hybrid Electric Vehicles Using Game Theory

Energy management strategy (EMS) of plug-in hybrid electric vehicle (PHEV) can coordinate the efficient coupling operation between multiple power sources, which is of great significance to the improvement of fuel economy and transmission efficiency. During the actual operation, EMS needs the electric drive system operate frequently to achieve excellent vehicle performance. In this case, the temperature of insulated gate bipolar transistor (IGBT) module inevitably increases and the thermal-mechanical stress caused by temperature fluctuation will lead to failure. To solve the above problems, a model predictive control (MPC)-based EMS considering IGBT temperature is proposed. Firstly, Markov chain-based driver model is built for the prediction of future vehicle speed. Secondly, according to the thermoelectric coupling model description of the IGBT module, a predictive energy management framework is constructed with fuel economy and IGBT temperature indexes as objective functions. Then, under the MPC framework, a non-cooperative game model with engine and IGBT as participants is established, and Nash equilibrium is taken as the solution. Finally, the simulation results indicate that the proposed strategy not only improves the fuel economy by 13.88% and 13.48% compared with the rule-based strategy under two driving conditions, but also effectively reduces the temperature of IGBT.

In Situ Diagnosis for IGBT Chip Failure in Multichip IGBT Modules Based on a Newly Defined Characteristic Parameter Low-Sensitive to Operation Conditions

To achieve the desired current capability, insulated gate bipolar transistor (IGBT) modules are normally composed of parallel chips. The bond wires fatigue on a certain chip will gradually cause the performance of the power module to degrade, and eventually lead to an unexpected catastrophic failure of the entire system. Therefore, this paper proposes an in-situ diagnosis method for bond wires fatigue in multichip IGBT modules based on a newly defined characteristic parameter. By sensitivity analysis, horizontal comparison and experimental test, the parameter was proven to have the advantages of being safe, low-sensitive to operation conditions and easy to extract. Correspondingly, the online monitoring circuit was designed on the basis of the voltage clamping technology, and further applied on an inverter prototype with 100 A peak current and 10 kHz switching frequency. The results showed that although with large change of junction temperature and load current, the proposed method can accurately diagnose IGBT chip failure by the sudden increase in the amplitude of the parameter. Moreover, the monitoring circuit can be both plug-and-play in the existing inverters and integrated in the gate drive circuit owing to the compact design, which is expected to avoid catastrophic failures of the inverter in field application.

Study on the temperature distribution of motor and inverter in an electric scroll compressor for vehicle air conditioning under refrigeration conditions

In the electric scroll compressor for vehicle air conditioning, the heat generated by motor and inverter is mainly taken away by suction gas. It is necessary to maintain the working temperature of motor and inverter within a safe range to void overheat or burnout. The temperature distribution of motor and inverter under refrigeration conditions are studied using computational fluid dynamics (CFD) simulation in this paper. At first, a CFD fluid-solid coupling simulation model is developed and verified by temperature measurement experiment. The maximum deviation between the simulated temperature at three points on the compressor housing and the measured results does not exceed ±3°C. Then the velocity and pressure distribution of fluid domain, and the temperature distribution of solid domains including the compressor housing, the stator coils and insulated gate bipolar transistor (IGBT) modules are analyzed. Next, the effects of operation conditions on the maximum working temperature and temperature distribution unevenness of stator coils and IGBT modules are discussed in detail. In addition, the working reliability of IGBT modules under refrigeration conditions is checked and the heat dissipation of IGBT modules is analyzed.

Study of the Solder Characteristics of IGBT Modules Based on Thermal-Mechanical Coupling Simulation.

The insulated-gate bipolar transistor (IGBT) represents a crucial component within the domain of power semiconductor devices, which finds ubiquitous employment across a range of critical domains, including new energy vehicles, smart grid systems, rail transit, aerospace, etc. The main characteristics of its operating environment are high voltage, large current, and high power density, which can easily cause issues, such as thermal stress, thermal fatigue, and mechanical stress. Therefore, the reliability of IGBT module packaging has become a critical research topic. This study focuses on the damage of power device solder layers and applies heat transfer theory. Three typical solders for welding IGBTs (92.5Pb5Sn2.5Ag, Sn3.0Ag0.5Cu (SAC305), and nano-silver solder paste) are analyzed using JMatPro software to simulate their characteristics. First, a finite element analysis method is used to simulate the entire IGBT module with ANSYS Workbench platform. The study compares the impact of three types of solders on the overall heat transfer of the IGBT module under normal operation and welding layer damage conditions. The characteristics are analyzed based on changes in the junction temperature, heat flow path, and the law of thermal stress and deformation. The findings indicated that under steady-state working conditions, adjacent chips in a multi-chip IGBT module had significant thermal coupling, with a maximum temperature difference between chip junctions reaching up to 13 °C, and a phenomenon of heat concentration emerged. The three types of solders could change the thermal conductivity and heat transfer direction of the IGBT module to varying degrees, resulting in a temperature change of 3-6 °C. Under conditions of solder layer damage, the junction temperature increased linearly with the severity of the damage. In the 92.5Pb5Sn2.5Ag and Sn3.0Ag0.5Cu (SAC305) solders, the presence of intermetallic compounds (IMCs) led to more stress concentration points in the solder layer, with the maximum stress reaching 7.14661 × 107 MPa and concentrated at the edge of the solder layer. The nano-silver solder layer had the best thermal conductivity, and the maximum thermal deformation under the same conditions was only 1.9092 × 10-5 m.