Insulated Gate Bipolar Transistor Gate Research Articles

Prediction of IGBT Gate Oxide Layer's Performance Degradation Based on MultiScaleFormer Network.

Insulated gate bipolar transistors (IGBTs) are widely used in power electronic devices, and their health prediction problems have attracted much attention in the field of power electronic equipment health management. The performance degradation of IGBT gate oxide is one of the most important failure modes. In order to analyze this failure mechanism and the ease of implementation of a monitoring circuit, the gate leakage current of IGBTs was selected as the fault precursor parameter for the degradation of their gate oxide performance, and feature selection and fusion were carried out by using time domain characteristic analysis, grayscale correlation, Mahalanobis distance, Kalman filter, and other methods. Thus, a health indicator was obtained to characterize the degradation of IGBT performance, which was used to indicate the degree of aging of the IGBT gate oxide layer. In this paper, we propose an improved degradation prediction model called MultiScaleFormer, inspired by advanced design ideas of the iTransformer network architecture, combined with the health parameters of IGBTs to construct a degradation prediction model for the IGBT gate oxide layer. MultiScaleFormer showed the highest fitting accuracy compared with the Long Short-Term Memory (LSTM), Convolutional Neural Network (CNN), Support Vector Regression (SVR), Gaussian Process Regression (GPR), CNN-LSTM, and Transformer models in our experiment. The mean absolute error (MAE) of the MultiScaleFormer prediction was as low as 0.0087. Extraction of the health indicator and the construction and verification of the degradation prediction model were carried out on the dataset released by the NASA-Ames Laboratory. These results demonstrate the feasibility of the gate leakage current as a fault precursor parameter for IGBT gate oxide failure, and the feasibility and accuracy of the MultiScaleFormer prediction model for IGBT performance degradation.

An Online Condition Monitoring Method for IGBT Gate Oxide Degradation Based on the Gate Current in Miller Plateau

The reliability of power converters is one of the important issues due to the widespread applications of power electronics in many industrial fields. Accordingly, condition monitoring (CM) methods for the assessment of the converter components health are considered as a practical topic for researchers and experts of the field. This paper aims to propose a CM method for insulated gate bipolar transistors (IGBTs) gate-oxide degradation. The proposed CM is based on the gate-emitter current during the turning-on process. It is shown that in the degradation process, the gate current peak value majorly increases. The proposed CM method captures this peak value and uses it as a degradation indicator. The proposed method is simple and analogous that can be served easily for online health assessment of the IGBTs under operation. It can be integrated into the driver module to assess the gate oxide degradation of the device. The functionality of the proposed method is evaluated using experimental prototyping. The target devices are a 1200 V, and 40 A trench-gate field-stop and a 600 V and 60 A planner gate punch-through (PT) discrete IGBTs. The achieved results show the validity and acceptable performance of the proposed CM for detecting the gate-oxide degradation of the device.

A Solid-State Circuit Breaker Without Current Limiting Inductor

This paper presents a high-density, high-efficiency megawatt (MW) medium-voltage (MV) solid-state circuit breaker (SSCB) for aviation hybrid electric propulsion applications. The proposed SSCB is based on the mature silicon (Si) insulated gate bipolar transistor (IGBT) devices. With reduced IGBT gate voltage, the proposed SSCB can limit the peak fault current without the fault current limiting inductor. Thus, the specific power density of the SSCB is substantially improved compared with the traditional design. This method has negligible impact on SSCB efficiency, reliability and energy absorbed by the metal-oxide varistor (MOV), while providing additional mechanical layout freedom for power density and insulation enhancement. The potential design challenges due to the extremely high ramp rate of the system fault current and the corresponding solutions are also discussed. The performance of the proposed SSCB is validated with experimental results.

Performance Degradation Modeling and Its Prediction Algorithm of an IGBT Gate Oxide Layer Based on a CNN-LSTM Network.

The problem of health status prediction of insulated-gate bipolar transistors (IGBTs) has gained significant attention in the field of health management of power electronic equipment. The performance degradation of the IGBT gate oxide layer is one of the most important failure modes. In view of failure mechanism analysis and the easy implementation of monitoring circuits, this paper selects the gate leakage current of an IGBT as the precursor parameter of gate oxide degradation, and uses time domain characteristic analysis, gray correlation degree, Mahalanobis distance, Kalman filter, and other methods to carry out feature selection and fusion. Finally, it obtains a health indicator, characterizing the degradation of IGBT gate oxide. The degradation prediction model of the IGBT gate oxide layer is constructed by the Convolutional Neural Network and Long Short-Term Memory (CNN-LSTM) Network, which show the highest fitting accuracy compared with Long Short-Term Memory (LSTM), Convolutional Neural Network (CNN), Support Vector Regression (SVR), Gaussian Process Regression (GPR), and CNN-LSTM models in our experiment. The extraction of the health indicator and the construction and verification of the degradation prediction model are carried out on the dataset released by the NASA-Ames Laboratory, and the average absolute error of performance degradation prediction is as low as 0.0216. These results show the feasibility of the gate leakage current as a precursor parameter of IGBT gate oxide layer failure, as well as the accuracy and reliability of the CNN-LSTM prediction model.

IGBT Gate Waveform Acquisition Based on Compressed Sensing Technology

As the core device of power electronic equipment, IGBT (Insulated Gate Bipolar Transistor) is related to the reliability of the system, so its online health monitoring is particularly important. Due to the large amount of data and high sampling rate for IGBT online health monitoring, data transmission has become a major problem, the method of effectively reconstructing the original signal has become one of the current research hotspots. Based on the theory of compressed sensing, the acquisition of IGBT gate waveforms is studied in this paper. First, the theoretical principle of compressed sensing is expounded and analyzed, and the evaluation criteria for signal reconstruction performance are given. Then, from the theory and simulation, the sparseness of IGBT gate drive signals under different sparse bases and different measurement matrices are discussed and analyzed. Next, aiming at the shortcomings of the stagewise weak orthogonal matching pursuit algorithm, a SWOMP algorithm based on the backtracking strategy of different Sigmoid functions is proposed. Simulation and experimental results show that the improved SWOMP4 algorithm has the best reconstruction effect. Finally, the SWOMP4 algorithm is applied to the process of IGBT gate drive signal reconstruction.This paper mainly collects and reconstructs the IGBT gate drive signal through the improved SWOMP4 algorithm. The designed algorithm has high reconstruction accuracy and can be used in the IGBT module online health status system.

Repeater coil‐based wireless power transfer system powering multiple gate drivers of series‐connected IGBTs

It is challenging to power a large number of gate drivers of the series-connected insulated gate bipolar transistors (IGBTs) in a high-voltage application because multiple isolated power supplies are needed. In this study, a novel wireless power transfer (WPT) system using repeater coils is designed to solve this problem. Every two repeater coils form a repeater unit, which transfers power to one load. With multiple repeater units in the system, multiple loads can obtain power simultaneously. To eliminate undesirable magnetic couplings between these coils, bipolar coils are used and the two bipolar coils in the same repeater unit are placed perpendicularly. It is derived that constant voltage can be obtained for all the loads, which is especially suitable for powering the IGBT's gate driver. Moreover, the variation of one load power will not affect others. The receiving circuit is designed to transform the received power to the DC voltage compatible with the driving circuits. An experimental setup with six loads has been constructed to validate the proposed WPT system.

The Influence of the Gate Driver and Common-Source Inductance on the Short-Circuit Behavior of IGBT Modules and Protection

In this article, the influence of the gate drive unit on the short-circuit (SC) type II and III behavior of insulated gate bipolar transistor (IGBT) modules was investigated in detail. It is found that the real gate voltage of the IGBT chip contacts cannot be measured across the auxiliary pins of a power module. The difference between applied gate voltage at the sense contacts and the real gate voltage at the IGBT gate contact is shown to be highly dependent on the common-source inductance and hence, the packaging concept. The value of the gate resistance has a significant effect on SC behavior. A gate voltage self-clamping effect during SC was found and verified with the help of circuit simulation. Finally, a gate voltage clamping circuit for improved SC ruggedness of the IGBT modules is introduced. Based on the clamping circuit, a new fast SC type II and III detection method is developed and tested, which can detect and turn- off the SC event within 400 ns.

Plug-in gate-loop compensators for series-connected IGBT drivers in solid-state fault current limiter

Solid-state fault current limiter (SSFCL) is the key protective equipment in direct current distribution network. To meet the high voltage requirement meanwhile reduce the cost, implementing a SSFCL based on series-connected insulated gate bipolar transistors (IGBTs) is a promising way. However, voltage unbalancing of IGBTs would be introduced if the gate-loops of the IGBTs are non-identical. In this paper, a plug-in gate-loop compensator with discrete gate voltage feedback and pulsewidth current compensation is proposed. The main merits are 1) with the plug-in structure, the extra current sources only provide small power to fine-tune the gate-loop without affecting the functions provided by the commercial IGBT gate driver; 2) the gate-emitter voltages of IGBTs are compared with the preset thresholds to obtain control criterions, and the pulsewidths of the current sources are controlled for gate-loop compensation, thus both analog-digital and digital-analog converters are avoided; 3) the control law is easy to be implemented in FPGA, and is robust to voltage variation of power-loop. With the proposed compensator, the voltage unbalancing is alleviated immediately at the present switching cycle, and further eliminated cycle-by-cycle during current limitation process. Experimental results verify the feasibility of proposed compensator.

Embedded Hardware Artificial Neural Network Control for Global and Real-Time Imbalance Current Suppression of Parallel Connected IGBTs

A global and real-time control with embedded hardware artificial neural network (ANN) for imbalance current suppression of parallel connected insulated gate bipolar transistors (IGBTs) is first proposed in this paper. This method focuses on control strategy and control execution. The former one is realized by porting the ANN-based PID (ANN-PID) strategy in the control loop to yield the real-time and adaptive characteristics without IGBT quantity limitation. The latter one is realized by designing the IGBT gate quantity of charge regulator (GQR) to execute the command from ANN-PID controller. The evaluation of ANN-PID algorithm results 0.023% mean error in IGBT current control that reveals the feasibility of the proposed method. A full prototype with FPGA-based hardware accelerator for ANN-PID computing, including the designed GQR circuit, has been built for realization and qualification in a buck converter with parallel connected IGBTs. The experimental results show that the performance of the proposed method in imbalance current suppression is improved about 3.5–5.5 times as the load increase from low to high with the advantage of immunity to load change and the current imbalance can be suppressed within 4%.

Crosstalk Analysis and Suppression for a Closed-Loop Active IGBT Gate Driver

This paper analyzes the crosstalk issues for a closed-loop active insulated gate bipolar transistor (IGBT) gate driver (AGD) based on di/dt and dv/dt detection and presents a crosstalk suppression (CTS) circuit. Closed-loop active gate drivers for IGBTs are beneficial in switching transient control by generating extra gate control signals to regulate the gate drive voltage or current with di/dt and dv/dt feedback. AGDs achieve the compensation of the IGBT nonlinearities and are independent of operating points. In a phase-leg configuration, however, AGDs produce additional crosstalk interference besides that due to reverse transfer capacitance. These two kinds of crosstalk interferences together lead to an oscillation in the IGBT gate voltage, and then a shoot-through fault may occur. An equivalent circuit model of the feedback circuit is presented to analyze and evaluate the crosstalk issues. The design and realization of a CTS circuit are presented to eliminate the crosstalk and extra gate drive losses caused by crosstalk. The experimental results substantiate the validity of the theoretical crosstalk analysis and the effectiveness of the proposed CTS circuit.

Balancing Algorithm for a Self-Powered High-Voltage Switch Using Series-Connected IGBTs for HVDC Applications

This paper presents a balancing algorithm for the so-called Director Switch, a controlled, reverse conducting, self-powered, high-voltage switch, using series-connected insulated gate bipolar transistors (IGBTs). This is a key component on two new voltage-source, high-voltage direct current (HVDC) converter topologies. These, which promise efficiency, cost, and size reductions, are an alternate arm converter and a series bridge converter. One of the main design challenges of the director switch is how to supply the IGBT gate drivers, and other auxiliary electronics while overcoming the high-voltage insulation barrier to ground level. In this paper, this is achieved by using the energy stored in a capacitive clamp snubber circuit, which also helps with the overvoltage mitigation during rare hard-switching events. However, the clamp capacitor and by proxy the IGBT voltages become highly unbalanced during operation, compromising the integrity of the switch. This paper presents a balancing strategy that consists in applying a controlled delay in the switching of the IGBT levels, in a way that forces a voltage balance on all the switch levels. The paper explains the unbalance. Then, the balancing strategy is explained and validated on simulation and on a high-voltage experimental rig, on switches comprising two and three series-connected IGBTs, respectively.

A Smart IGBT Gate Driver IC With Temperature Compensated Collector Current Sensing

Conventional insulated gate bipolar transistor (IGBT) current sensing and protection techniques usually employ discrete sensors, such as lossy shunt resistors, and may involve accessing the high-voltage collector load of the IGBT. This would normally present difficulties for integration. This paper presents an IGBT gate driver IC with a collector current sensing circuit and an on-chip CPU for local data processing. This IC is prototyped using a TSMC 0.18 μm 40 V BCD Gen-2 process. The collector current sensing technique is based on the unique Miller plateau relationship between the gate current and collector current ( $I_{C}$ and $I_{G}$ ) for a particular gate resistance ( $R_{G}$ ). It allows a cycle-by-cycle measurement of IC during both turn- on and turn- off transients without any extra discrete components. The temperature variation is compensated internally by the on-chip CPU using polynomial curve fitting. This technique only monitors the low-voltage signal at the gate terminal, without the need to handle any high-voltage signal on the collector/load side. Measurements using a double pulse test setup show an accuracy of ±0.5 A over the current ranges of 1–30 A for turn- on and 1–50 A for turn- off from 25 to 75 °C.

Indirect IGBT Over-Current Detection Technique Via Gate Voltage Monitoring and Analysis

This paper presents a new insulated gate bipolar transistor (IGBT) over-current detection method based on the analysis of the gate voltage waveform. The IGBT's gate voltage turn-on transient pattern is analyzed for the detection of IGBT hard switching fault (HSF). The on-state gate voltage is monitored to detect IGBT fault under load (FUL). The IGBT's turn-off Miller plateau voltage is extracted and measured to sense the IGBT collector current in case of an over-load condition. Compared to the commonly used IGBT short-circuit detection methods or collector current sensing methods, this method can provide indirect fast detection of IGBT short circuit and accurate measurement of over-load within one switching period. The feasibility and effectiveness of the proposed approach are validated both by simulation and experimental results. Measurement results show that HSF and FUL can be detected within 0.6 and 0.5 μs, respectively. By comparing the extracted plateau voltage (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PL</sub> ) with a preset reference voltage (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">OCx</sub> ), the IGBT over-load can be detected with a maximum deviation of ±1.2 A when IC ranges from 3 to 110 A.

철도차량용 IGBT Gate Driver Unit 기술 동향 분석 연구

철도차량용 전원창치는 추진제어용 전원장치와 보조전원장치로 구분된다. 추진제어용 전원장치는 철도차량의 추진 및 회생제동 등의 동작을 위한 것이며, 보조전원장치는 추진제어용 전원을 제외한 공기압축기, 조명기기, 차량제어전원 등의 보조전원에 사용되는 것이다. 각 전원장치는 고전압, 고전류 사양 특성에 따라 일반적으로 insulated-gate bipolar transistor (IGBT)를 스위칭 소자로 사용하고 있다. 스위칭 소자를 사용하기 위해서는 적절한 스위칭 동작을 구현하기 위한 구동회로(Gate Driver Unit, GDU)가 필수적이다. 본 논문에서는 철도차량에 적용되고 있는 IGBT용 GDU에 적용되고 있는 기술 동향을 분석하고 철도차량용 IGBT GDU 설계 시 고려사항에 대해 알아보고자 한다. Power supply for railway cars can be divided into propulsion system power supply and auxiliary power units (APU). The propulsion system power supply is for propulsion of railway cars, and regenerative braking; the APU provides power for the air compressor, lighting, car control and other auxiliary parts. According to high voltage and high current specifications, generally, an insulated-gate bipolar transistor (IGBT) is adopted for the switching component. For appropriate switching operation, a gate driver unit (GDU) is essentially required. In this paper, the technical trends of GDU for railway cars are analyzed and a design consideration for IGBT GDU is described.

전기자동차용 이중 게이트 구조를 갖는 전력 IGBT소자의 전기적인 특성 분석

본 논문에서는 플래너 게이트 및 트렌치 게이트의 구조를 동시에 가지고 있는 1200V급 이중 게이트 IGBT 소자를 제안함과 동시에 전기적인 특성을 분석하였으며, 분석된 결과를 가지고 플래너 게이트 및 트렌치 게이트 IGBT 소자의 전기적인 특성과 비교 분석하였다. 이중 게이트 IGBT 소자를 설계하는데 있어 문턱전압 및 온 상태 전압 강하에 영향을 주는 P-베이스 영역에 있어 P-베이스에 깊이는 트렌치 게이트 소자 영역에 영향을 주며, P-베이스에 너비는 플래너 게이트 소자 영역에 영향을 주는 것을 확인할 수 있었다. 본 연구에서 제시한 이중 게이트 IGBT 소자의 전기적인 특성인 항복전압은 1467.04V, 온 전압 강하는 3.08V, 문턱전압은 4.14V의 특성을 나타내고 있다. IGBT (Insulated Gate Bipolar Transistor) device is a device with excellent current conducting capability, it is widely used as a switching device power supplies, converters, solar inverter, household appliances or the like, designed to handle the large power. This research was proposed 1200 class dual gate IGBT for electrical vehicle. To compare the electrical characteristics, The planar gate IGBT and trench gate IGBT was designd with same design and process parameters. And we carried to compare electrical characteristics about three devices. As a result of analyzing electrical characteristics, The on state voltage drop charateristics of dual gate IGBT was superior to those of planar IGBT and trench IGBT. Therefore, Aspect to Energy Loss, dual gate IGBT was efficiency. The breakdown volgate and threshold voltage of planar, trench and dual gate IGBT were 1460V and 4V.

Modern IGBT gate driving methods for enhancing reliability of high-power converters — An overview

This paper presents a survey of existing gate driving approaches for improving reliability of Insulated Gate Bipolar Transistors (IGBTs). An extensive and various lists of techniques are introduced and discussed, including fast detection, identification and protection against IGBT failures, also considering cost-effective solutions. Gate-driver circuit solutions to improve short-circuit robustness, overload, voltage and current overshoots withstanding capability are first introduced to cope with abnormal conditions severely affecting lifetime expectation. Later, some advanced, state-of-the-art control techniques are discussed to minimize the real-mission-profile stresses in terms of voltage and current stresses to the device, together with, not least, temperature variations. Future challenges and perspectives are finally discussed at the end of the paper.

&lt;italic&gt;In Situ&lt;/italic&gt; Diagnostics and Prognostics of Solder Fatigue in IGBT Modules for Electric Vehicle Drives

This paper proposes an in situ diagnostic and prognostic (D&P) technology to monitor the health condition of insulated gate bipolar transistors (IGBTs) used in EVs with a focus on the IGBTs' solder layer fatigue. IGBTs' thermal impedance and the junction temperature can be used as health indicators for through-life condition monitoring (CM) where the terminal characteristics are measured and the devices' internal temperature-sensitive parameters are employed as temperature sensors to estimate the junction temperature. An auxiliary power supply unit, which can be converted from the battery's 12-V dc supply, provides power to the in situ test circuits and CM data can be stored in the on-board data-logger for further offline analysis. The proposed method is experimentally validated on the developed test circuitry and also compared with finite-element thermoelectrical simulation. The test results from thermal cycling are also compared with acoustic microscope and thermal images. The developed circuitry is proved to be effective to detect solder fatigue while each IGBT in the converter can be examined sequentially during red-light stopping or services. The D&P circuitry can utilize existing on-board hardware and be embedded in the IGBT's gate drive unit.

Fault Detection for IGBT Using Adaptive Thresholds During the Turn-on Transient

This paper presents the analysis and design of an electronic failure detection system applied to the insulated gate bipolar transistor (IGBT), this proposal is based on the direct measurement of behavior of the gate signal during the turn-on transient. The failures by short-circuit and open-circuit devices only are considered in this paper. To achieve early detection, the IGBT gate signal behavior during turn-on transient is used and to increase the effectiveness of the detection and to tolerate the variations of input to system, adaptable thresholds have been added to the analog electronics circuit implemented. The experimental tests are presented in order to validate the proposed fault-detection technique.

Dynamic Characterization of Parallel-Connected High-Power IGBT Modules

In high-power converter design, insulated gate bipolar transistor (IGBT) modules are often operated in parallel to reach high output currents. Evaluating the electrical and thermal behavior of the parallel IGBTs is crucial for the design and reliable operation of converter systems. This paper investigates the static and dynamic characterization of parallel IGBTs and the influence of the electrical parameters on the IGBT behavior. Si-based IGBT power modules with voltage rating of 4.5 kV and current rating of 1 kA are used for the experimental evaluation of module parallel connections. Parallel-connected modules have been driven by several commercial IGBT gate units at various dc-link voltages and current levels and with different temperatures. The tested IGBT gate units show good current sharing performance between the two parallel modules. Other important influencing factors such as busbar design layout, stray inductance variation, and gate driving are also investigated for parallel connections of IGBT modules. Finally, the switching energy of the parallel modules is extracted for IGBTs and diodes under different conditions.

A rugged 650 V SOI-based high-voltage half-bridge IGBT gate driver IC for motor drive applications

This paper proposes a rugged high-voltage N-channel insulated gate bipolar transistor (IGBT) gate driver integrated circuit. The device integrates a high-side and a low-side output stages on a single chip, which is designed specifically for motor drive applications. High-voltage level shift technology enables the high-side stage of this device to operate up to 650 V. The logic inputs are complementary metal oxide semiconductor (CMOS)/transistor transistor logic compatible down to 3.3 V. Undervoltage protection functionality with hysteresis characteristic has also been integrated to enhance the device reliability. The device is fabricated in a 1.0 μm, 650 V high-voltage bipolar CMOS double-diffused metal oxide semiconductor (BCD) on silicon-on-insulator (SOI) process. Deep trench dielectric isolation technology is employed to provide complete electrical isolation with advantages such as reduced parasitic effects, excellent noise immunity and low leakage current. Experimental results show that the isolation voltage of this device can be up to approximately 779 V at 25°C, and the leakage current is only 5 nA at 650 V, which is 15% higher and 67% lower than the conventional ones. In addition, it delivers an excellent thermal stability and needs very low quiescent current and offers a high gate driver capability which is needed to adequately drive IGBTs that have large input capacitances.