Insulated Gate Bipolar Transistor Switching Research Articles

Electrothermal Modeling of the Insulated Gate Bipolar Transistor (IGBT) Using PSpice: Application to DC–DC Converter

In this paper, an improved electrothermal model of power IGBT was developed. The main local physical effects were taken into consideration. The suggested model is able to address the electrical and thermal effects. The model was confirmed through a comparison with other models having close characteristics for different circuits (DC–DC converter, turn-on and turn-off) and different temperatures. The IGBT model was implemented in the PSpice circuit simulation platform using PSpice standard components and analog behavior modeling (ABM) blocks. The IGBT switching performance was investigated under influence of different circuit elements (such as stray inductance, gate resistance and temperature) in order to study and estimate the on-state and switching losses pre-requisite for the design of various converter and inverter topologies. The comparison shows that these models are simple, tunable with the electric circuit software simulator. They are more capable of predicting the main circuit parameters needed for power electronic design. The transient thermal responses were demonstrated for the single pulse and repeat modes. The achieved results show that our model is suitable for full electrothermal simulations of power electronic circuits.

Improve the reliability of the ion source beam extraction by adopting a solid-state suppress electron power supply.

A solid-state suppress grid power supply (SGPS) is developed to be applied to the 5 MW level neutral beam injection (NBI) on HL-2M Tokamak. The power supply consists of ten modules in series, with an index of 560 V/40 A. Each of the modules is composed of an isolated transformer, rectifier, filter tank, insulated gate bipolar transistor switch, gate-drive circuit, free-wheeling diode, and so forth. An embedded system STM32F103 is used for controlling and protecting the SGPS. Meanwhile, the transient output capacity of the SGPS is tested. The effect of the output voltage of the SGPS on the extracted beam current is studied. The experimental results show that there is a turning point in the relationship between the suppress voltage and the extracted beam current. When the rate of the absolute value of the suppress voltage and the gradient voltage is more than 2.5%, the efficiency of the extracted beam of the ion source can be improved. Compared with the previous types of equipment of the NBI system, the extracted beam success rate of the new SGPS increased by more than 20%. The SGPS meets the requirements of the NBI system.

Design and implementation of secured power grid system with information and communication technology

This study presents a novel power grid system, for monitoring and controlling a power grid that is made up of various power sources, by using Information and Communication Technologies ICT. This can be hugely contributed to improving the reliability, efficiency as well as towards making smart and automated power systems. The current model was developed in the MATLAB Simulink environment. The proposed system consists of a PV panel, battery, power grid, ICT system/controller, and loads. There are four insulated-gate bipolar transistor switches; namely, IGBT to control battery charging/discharging status and to connect or disconnect either PV panel power source or grid power source depending on the load. The main aim of this model is to develop and implement a grid-connected system that is integrated with PV panel and battery in MATLAB to analyze various operations modes, which include the performance of the PV panel and battery during both the online and offline modes of operation. The proposed system is said to be capable to monitor and control different power sources, which in turn will lead not only to reducing dependence on non-renewable energies but also to increasing dependence on renewable energies. The simulation results were illustrated and demonstrated that the proposed system can monitor and control the power generated and transmission in real-time in a better and secure manner. On the other hand, exploiting this model leads to reduce the power production costs, creating a clean environment, and also to preserve long term battery life.

Calculation of Semiconductor Power Losses of a Three-Phase Quasi-Z-Source Inverter

This paper presents two novel algorithms for the calculation of semiconductor losses of a three-phase quasi-Z-source inverter (qZSI). The conduction and switching losses are calculated based on the output current-voltage characteristics and switching characteristics, respectively, which are provided by the semiconductor device manufacturer. The considered inverter has been operated in a stand-alone operation mode, whereby the sinusoidal pulse width modulation (SPWM) with injected 3rd harmonic has been implemented. The proposed algorithms calculate the losses of the insulated gate bipolar transistors (IGBTs) and the free-wheeling diodes in the inverter bridge, as well as the losses of the impedance network diode. The first considered algorithm requires the mean value of the inverter input voltage, the mean value of the impedance network inductor current, the peak value of the phase current, the modulation index, the duty cycle, and the phase angle between the fundamental output phase current and voltage. Its implementation is feasible only for the Z-source-related topologies with the SPWM. The second considered algorithm requires the instantaneous values of the inverter input voltage, the impedance network diode current, the impedance network inductor current, the phase current, and the duty cycle. However, it does not impose any limitations regarding the inverter topology or switching modulation strategy. The semiconductor losses calculated by the proposed algorithms were compared with the experimentally determined losses. Based on the comparison, the correction factor for the IGBT switching energies was determined so the errors of both the algorithms were reduced to less than 12%.

Switch Open-Fault Detection for a Three-Phase Hybrid Active Neutral-Point-Clamped Rectifier

This paper proposes a fault-detection method for open-switch failures in hybrid active neutral-point-clamped (HANPC) rectifiers. The basic HANPC topology comprises two SiC-based metal-oxide-semiconductor field-effect transistors (MOSFETs) and four Si insulated-gate bipolar transistors (IGBTs). A three-phase rectifier system using the HANPC topology can produce higher efficiency and lower current harmonics. An open-switch fault in a HANPC rectifier can be a MOSFET or IGBT fault. In this work, faulty cases of six different switches are analyzed based on the current distortion in the stationary reference frame. Open faults in MOSFET switches cause immediate and remarkable current distortions, whereas, open faults in IGBT switches are difficult to detect using conventional methods. To detect an IGBT fault, the proposed detection method utilizes some of the reactive power in a certain period to make an important difference, using the direct-quadrant (dq)-axis current information derived from the three-phase current. Thus, the proposed detection method is based on three-phase current measurements and does not use additional hardware. By analyzing the individual characteristics of each switch failure, the failed switch can be located exactly. The effectiveness and feasibility of the proposed fault-detection method are verified through PSIM simulations and experimental results.

Development of a five-stage solid-state linear transformer driver.

In this paper, the development of a five-stage solid-state linear transformer driver (LTD) is described. Each stage consists of eight compact pulse generating modules and a magnetic core. The pulse generating modules contain a multilayer-ceramic-capacitor-based pulse-forming network (PFN) and an insulated-gate bipolar transistor (IGBT) switch array, as well as magnetic switches, which are used to speed up the pulse front. To prevent damage from the reverse voltage to the IGBT switch, a reverse voltage absorption circuit was added to the PFN. For this study, a larger cross-sectional core with improved output characteristics was adopted. The developed five-stage LTD has the advantages of long life, low jitter, fast rising edge, and so on. The device can provide a 35 kV, 119 ns, 4.3 kA square pulse train with a maximum frequency of 50 Hz. On this basis, a 50-stage LTD of output 500 kV, which would serve as a high-power microwave driver source, is under development.

The Influence of Driving Parameters on Conducted EMI for an IGBT Module

Insulated gate bipolar transistor (IGBT) has been widely used in the voltage-source-converter-based high-voltage direct current (VSC-HVDC). However, the electromagnetic interference (EMI) generated by its fast switching process affects the normal operation of the surrounding power equipment. The switching voltage and current of IGBT are the main sources of EMI. Different driving circuit parameters result in different IGBT switching characteristics. In this article, the switching model of IGBT is introduced first and the influence of driving parameters on EMI sources is analyzed. Based on the conducted EMI experiment platform of an IGBT module, the time-domain waveforms of switching voltage and current under different driving parameters are obtained and compared with the model. Then the interference voltage spectrums are measured by an EMI receiver under different driving parameters. The influence of driving parameters on conducted EMI in 0.15–30 MHz is then analyzed and explained by combining the result of time domain and frequency domain. This article comprehensively analyzes the relationship between driving parameters and EMI sources and summarizes the influence characteristics of driving parameters on common-mode (CM) and differential-mode (DM) noise. The conclusions can help the parameters design of driving board, which can effectively reduce the conducted EMI of the converter.

Characteristics and Influence Factors of Radiated Disturbance Induced by IGBT Switching

The setup for testing radiated disturbance induced by insulated gate bipolar transistor (IGBT) and auxiliary circuits was established. The radiated disturbance characteristics of auxiliary circuits and methods to suppress the radiated electromagnetic interference (EMI) were experimentally studied. The radiated EMI bandwidth of the auxiliary circuit was concentrated in the range 30–300 MHz. The mathematical model for an IGBT was proposed based on the setup, which includes all the structures of the IGBT in detail. The electric fields were calculated from the IGBT model using the method of moments. Moreover, the characteristics of the radiated disturbances due to the IGBT operation and the effects of metal on the radiated electric fields were experimentally and calculatingly studied in the frequency range 1–30 MHz. The metal shielded box of drive can increase the radiated electric fields by approximately 10–30 dB in the range 1–30 MHz. The electric fields for all the frequencies decreased rapidly with the increase of distance. Additionally, methods to shield the IGBT in order to suppress the radiated EMI were proposed. The effective radiated EMI reduction from a shielded net was approximately 20 dB, and that of a shielded box was around 30 dB.

IGBT Series Connection With Soft Switching and Power Recovery in Driver Power Supply

The emergence of applications which require high-voltage switches has created a tendency to use semiconductor device series stacks. These series stacks permit operation at blocking voltages above semiconductor elements’ nominal voltage. Insulated-gate bipolar transistors (IGBT) are currently utilized for controllability and switching speed, when these topologies are employed. The main challenge therewith is guaranteeing voltage balance between IGBTs, both when blocked and when switching transistors. Most of the methods which have been proposed to mitigate static and dynamic voltage unbalances increase transistor losses. The series stack loss-less high voltage switch (LHVS) which mitigates voltage unbalances, thus reducing switching losses, is presented in this paper. LHVS consists of a circuit, which ensures soft IGBT switching, an energy recovery circuit, and a gate delay compensation circuit. Additionally, the insulation voltage level is guaranteed to be equal between control circuit and high-voltage side of each IGBT. The operating principle of the LHVS is detailed in this paper, as is experimental validation which has been performed for three series stack modules. Static unbalances are reduced to 1%, while the differences between collector–emitter voltage curves in switching “ on ” do not surpass 8 ns, and switching losses are reduced by 41%, as compared to the hard-switching topology.

Self-Adaptive Active Gate Driver for IGBT Switching Performance Optimization Based on Status Monitoring

Compared to the conventional gate driver for the insulated gate bipolar transistor (IGBT), the active gate driver (AGD) not only reduces the switching delay but also suppresses voltage or current overshoot, however, at the expense of increasing the switching losses unavoidably. In this article, a self-adaptive active gate driver (SAGD) is proposed to further optimize IGBT switching performance, which is particularly suitable for applications where the load current varies over time or the dc bus voltage is changed. Since in such applications, AGD with fixed overshoot suppression ability will cause unnecessary switching loss, especially when the load current or the dc bus voltage is low. In contrast, with neither A/D nor D/A converters applied, the proposed SAGD indirectly detects the load current and dc bus voltage as time quantities, based on status monitoring, then self-adaptively chooses the optimal gate resistance increment online during the specific voltage or current rising phase. In this way, the current or voltage with overshoot is suppressed to be inside the safe operation area of IGBT while the switching loss is minimized, thus a better tradeoff between overshoots and switching losses is achieved. Finally, the feasibility of the proposed SAGD is verified by experiments.

Nanoseconds Switching Time Monitoring of Insulated Gate Bipolar Transistor Module by Under-Sampling Reconstruction of High-Speed Switching Transitions Signal

An insulated gate bipolar transistor (IGBT) is one of the most reliable critical components in power electronics systems (PESs). The switching time during IGBT turn-on/off transitions is a good health status indicator for IGBT. However, online monitoring of IGBT switching time is still difficult in practice due to the requirement of extremely high sampling rate for nanoseconds time resolution. The compressed sensing (CS) method shows a potential to overcome the technical difficult by reducing the sampling rate. To further improve the efficiency and reduce the computational time for IGBT online condition monitoring (CM), an under-sampling reconstruction method of an IGBT high-speed switching signal is presented in this paper. First, the physical mechanism and signal characteristics of IGBT switching transitions are analyzed. Then, by utilizing the sparse characteristics of IGBT switching signal in the wavelet domain, the wavelet basis is used for sparse representation. The stagewise orthogonal matching pursuit (StOMP) algorithm is proposed to enhance the convergence speed for switching signal reconstruction. Experiments are performed on not only a double-pulse test rig but also a real Pulse-Width Modulation (PWM) converter. Results show that the IGBT high-speed switching transitions signal can be accurately recovered with a reduced sampling rate and the nanoseconds switching time change can be monitored for IGBT CM.

A Series Stacked IGBT Switch Based on a Concentrated Clamp Mode Snubber for Pulsed Power Applications

Clamp mode snubbers are very well suited for the series structure of the insulated-gate bipolar transistors (IGBTs) in pulsed power applications. They properly meet the necessities expected from them such as the fast operating of the series IGBTs since they have no effect on the gate side. In addition, they can provide safe voltage condition for the IGBTs in short circuit faults, which are very probable in pulsed applications. The clamp mode snubber can perform its voltage balancing task whenever the power capacity of the snubber can support the injected powers due to the voltage unbalancing factors. This paper initially introduces the main factors injecting power to the snubbers. Then, it will be illustrated that the exact injected power to each predetermined snubber cannot be determined due to the uncertainties about the effect of the voltage unbalancing factors. Although it is impossible to determine the exact value of the power injected to each snubber, the total injected powers to the snubbers can be calculated. Therefore, as an effective remedy, this paper proposes a concentrated snubber. Using the proposal, all the injected powers are conducted to a centralized circuit and can be easily managed. In addition, analytical expressions are provided for proper dimensioning of the proposed concentrated snubber elements. Furthermore, the performance of the proposed concentrated snubber is evaluated using simulations and experimental prototyping.

An FPGA-Based IGBT Behavioral Model With High Transient Resolution for Real-Time Simulation of Power Electronic Circuits

This paper presents a novel insulated gate bipolar transistor (IGBT) behavioral model on the field programmable gate array (FPGA), which is suitable for the real-time simulation of fast transients in power electronics circuits. In this model, the static and dynamic behaviors of the IGBT switch are described and modeled separately. The static IGBT model is represented by the saturation region of output characteristic and is a part of the circuit network model. The dynamic IGBT model is combined with the static one to describe the fast switching transient behaviors by using the IGBT equivalent circuit model. The presented dynamic model in this paper does not involve any iterative solving algorithm and can be designed with highly pipelined structures on FPGA. Therefore, the IGBT switching transient waveforms can be generated precisely with a 5 ns resolution. The proposed model is tested with two cases—a four-phase floating interleaved boost converter and a three-phase five-level modular multilevel converter. The effectiveness and accuracy of the model are validated by comparing the real-time simulation results with offline simulation software.

A High-Voltage Series-Stacked IGBT Switch With Active Energy Recovery Feature for Pulsed Power Applications

Applying series configuration of the insulated gate bipolar transistors (IGBTs) to the pulsed power supplies offers unique features such as compactness and long life time. In the high-voltage pulsed power supplies, a large number of the IGBTs are required to be serially connected. Hence, the safe operating condition provision for the series IGBTs is an important and crucial issue. The effect of the voltage unbalancing factors becomes remarkable when the number of switches in the series structure increases. There are passive and active methods to balance the voltage of the series IGBTs. In both of these methods, an amount of power must be dissipated to remove the effect of the voltage unbalancing factors. Consequently, the power loss is considerable when a large number of series devices are necessary. This paper proposes an effective power recovery system that recovers the power associated with the series stacking of the IGBTs. Using this proposal, the efficiency of the resulted series switch enhances considerably. The power recovery system can be implemented easily for any number of series IGBTs. It consists of a simple dc–dc converter and several interconnection diodes for power recovery procedure. Proper performance of the proposed structure is evaluated by the aid of simulations and experiments.

Compressed Sensing Method for IGBT High-Speed Switching Time On-Line Monitoring

Condition monitoring (CM) has been considered as a promising technique to improve the reliability of insulated gate bipolar transistors (IGBTs). Among various condition parameters, switching time is a good health status indicator to detect IGBT failures. However, on-line monitoring of the IGBT high-speed switching time is still difficult in practice due to the requirement of the extremely high sampling rate for signal acquisition. To overcome the technical difficulty, this paper provides an innovative compressed sensing (CS) method to achieve equivalent sampling performance for high-speed IGBT switching time monitoring with a lower sampling rate. By utilizing the sparse characteristics of an IGBT switching signal, the sampling rate in the CS method could be far less than the traditional Nyquist sampling rate. To clarify the method, the CM mechanism using IGBT switching time is first analyzed. Then, three key points in the CS method are studied, i.e., the selection of sparsifying basis, the design of a measurement matrix, and the implementation of a reconstruction algorithm. Finally, experiments are carried out to investigate the performance of the CS method for on-line CM. Experimental results show that the IGBT turn- off time at different temperatures can be accurately monitored with a highly compressed sampling rate, which validates the feasibility and effectiveness of the proposed method.

A New Hybrid Multilevel DC–AC Converter With Reduced Energy Storage Requirement and Power Losses for HVDC Applications

A dc-ac converter for voltage-source converter (VSC)-HVdc technology has a significant influence on the performance of the entire power transmission system. This paper introduces a new dc-ac converter composed of submodules and series insulated-gate bipolar transistor (IGBT) switches. The basic idea of this hybrid solution is to shape the ac voltage by submodules but, per half cycle, reconnect them to different electrical points by IGBT switches. This concept can help to reduce the quantities of submodules, thereby reducing the energy storage requirement significantly. Another advantage is that the IGBT switches can be soft switched by utilizing the high controllability of the submodules. This brings extra benefit of power losses reduction. In this paper, the operating principle of this hybrid converter is explained. Its performances are also presented in detail and compared with those popular VSC dc-ac converters. The feasibility of the new concept is also verified by simulation and experimental results.

Sensorless Speed Control of Five-Phase PMSM Drives in Case of a Single-Phase Open-Circuit Fault

This paper introduces a new method to track saliency in a five-phase permanent magnet synchronous motor in case of a single-phase open-circuit fault. The proposed method depends on measuring the dynamic current response of the motor line currents due to the insulated-gate bipolar transistor switching actions. In case of a single-phase open-circuit fault, a fault-tolerant control strategy to control the remaining healthy currents results in minor system performance degradation. The new strategy that is proposed in this paper to track the saliency includes software modifications only to the saliency tracking algorithm used in healthy mode in order to make it applicable in the cases of a single-phase open-circuit fault. It uses the fundamental pulse width modulation waveform obtained using a symmetric multi-phase space vector pulse width modulation only. Simulation results are provided to verify the effectiveness of the proposed design over a wide speed range under different load conditions.

Hybrid Nonlinear Transmission Lines Used for RF Soliton Generation

Nonlinear transmission lines (NLTLs) have been studied for high-power RF generation with good prospects of applications in pulse radars for remote sensing (SARs) and disruption of communications in the battlefield, for instance. In this paper, two 30-section hybrid NLTLs built using nonlinear inductors and capacitors (2.2- and 10-nF barium titanate ceramic capacitors with 10- $\mu \text{H}$ ferrite bead inductors) will be described. For the test, the line is fed by a negative input pump pulse generated by a 1 kV discharge of a 0.75- $\mu \text{F}$ storage capacitor via a fast 50-ns switching system composed by an insulated gate bipolar transistor switch and its gate circuit driver. In the hybrid line tests, using 2.2-nF ceramic capacitors the maximum soliton generation packet obtained on the middle section had a frequency of the order of 33 MHz with voltage modulation depth (VMD) of around 700 V. For every single shot, approximately 10 RF cycles with small damping were noted. With the hybrid line using 10-nF ceramic capacitors the soliton generation obtained on the middle section reached a frequency of the order 10 MHz, and VMD of around 200 V. The main conclusion from this experiment is that hybrid lumped NLTLs may be used to achieve RF in megahertz range with higher VMD compared their counterparts (i.e., capacitive or inductive lines) because of their stronger nonlinearity with the use of both nonlinear elements.

Research on a novel variable-frequency and phase-shift control method based on a high-voltage and high-power full-bridge converter

This paper presents a new variable-frequency phase-shift control method to improve the conversion efficiency for a high-power wide-range converter based on a phase-shifted full-bridge (PSFB) converter. The proposed converter can adjust the switching-frequency according to the load power to make the input impedance be inductive. The main switches of the converter can achieve zero voltage switching (ZVS) over a wide load range (500 W–50 kW) without any auxiliary circuit. The maximum switching-frequency of high-power insulated gate bipolar transistor (IGBT) is determined by analyzing the influence of collector current on IGBT switching time. The necessary condition for the proposed converter to realize ZVS is given according to the steady-state model of the full-bridge converter. This paper analyzed the influence of voltage, current and temperature on the switching time of high-power IGBT in detail, and obtained the relationship between the load current and the dead time of high-power IGBT. The optimal switching-frequency under different loads was determined by establishing a switching-frequency loss model of the proposed converter. A 50 kW prototype of the proposed converter was developed and the experimental and simulation results verify the effectiveness and efficiency of the proposed method.

Experimental study on the influence of junction temperature on the relationship between IGBT switching energy loss and device current

Accurate determination of power losses in semiconductor devices is important for optimal design and reliable operation of a power converter. The switching loss is an important component of the total device loss in an insulated-gate bipolar transistor (IGBT) in a voltage source inverter. The objective here is to study experimentally the influence of junction temperature on the turn-on switching energy loss Eon and turn-off switching energy loss Eoff. More specifically Eon and Eoff are both related to device current Ic; the influence of junction temperature on the relationship between Eon and Ic and that between Eoff and Ic is studied. As the operating environmental conditions and load conditions of power converter vary widely, a wide range of junction temperatures between −35°C and +125°C is considered here. The experimental data enable precise determination of the switching loss in each device in a high-power converter at any practical operating condition. This leads to precise estimation of total device loss and optimal thermal design of the converter. This further helps off-line and/or on-line estimation of device junction temperatures required for study of thermal cycles and reliability.