Three-phase Insulated Gate Bipolar Transistor Research Articles

Modeling and simulation of three-phase IGBT full-bridge inverter circuit based on FPGA

The field of motor drive makes extensive use of electronic power modeling and simulation of three-phase IGBT full-bridge inverter circuits. The accuracy and computational efficiency of these models have a direct impact on the dependability of the motor control system. The majority of earlier research focused solely on static processes of turning on and off in IGBTs, disregarding the transient proesses that occur when three-phase IGBT full-bridge inverter circuits are switched at high frequencies. This has an impact on the circuits' accuracy in real-time simulation. Therefore, this paper proposes and builds a field-programmable logic gate array (FPGA)-based steady-state and transient dual-phase three-phase IGBT full-bridge inverter circuit model for the static and transient characteristics of the insulated gate bipolar transistor (IGBT) element in the circuit. Depending on whether or not the switching states of the six IGBTs in the three-phase IGBT full-bridge inverter circuit are altered, the simulation process is split into steady state and transient phases. In the steady state phase with large step size, the circuit is discretized using the binary L/C approach. In the transient phase, the transient process is divided into several small-step-long time domains. Real-time simulation waveforms are generated by interleaving and combining the multistage fitting method's solution of the circuit's transient waveforms at tiny step lengths with the steady state phase. Finally, in order to demonstrate the accuracy of the circuit model in this work, the simulation results of the two-stage three-phase IGBT full-bridge inverter circuit model based on FPGA are compared with those of the conventional ideal model for waveform comparison and data analysis.

Single PCB sensor-based output current reproduction for three-phase inverter systems

This study proposes a practical output current measurement system in a three-phase inverter with a single printed circuit board (PCB) Rogowski coil sensor inserted in the bus between the DC-link capacitor and the power semiconductor module. This system demonstrates its advantage over conventional output current sensors, such as the Hall effect current sensors, in terms of the size, weight, operation temperature and cost. The system can be applied to 6-in-1 power modules as it does not require sensors in the inverter phase legs.In our previous works, we have developed a method called “envelope tracking”, which is used in this system as well. This method traces the switching current instead of the output current to reproduce the output current signal in real-time. Envelope tracking successfully reproduced the output current waveform for single phase inverters under certain conditions. However, a large error is observed in the three-phase inverter demonstration under a high switching frequency (narrow pulse) or when the switching of different phases overlap each other. These errors must be completely suppressed to implement the system for feedback control in three-phase inverters.In this study, a new analog basis output current waveform reproduction system is introduced to suppress the above mentioned errors. This system is implemented in a three-phase insulated-gate bipolar transistor (IGBT) inverter and successfully reproduces the output current with a single PCB sensor inserted between a 6-in-1 IGBT power module and DC-link capacitor, operating under a switching frequency of 3.5–7.0 kHz and output current of 6 A with DC-link voltage of 150 V.

Novel schemes used for estimation of power system harmonics and their elimination in a three-phase distribution system

Estimation of power system harmonics and their elimination is an interdisciplinary area of interest for many researchers. This paper presents Variable Step Size Least Mean Square (VSS-LMS) approach for harmonics estimation and Shunt Active Power Filter (SAPF) with two-level Hysteresis Current Control (HCC) technique for their elimination in a three-phase distribution system. In the estimation process, the weight is updated using VSS-LMS algorithm. Harmonics components are estimated from the updated weights. In order to mitigate harmonics produced by the nonlinear load connected in a three-phase distribution system, SAPF with two-level HCC is proposed. A three-phase insulated gate bipolar transistor (IGBT) based current controlled voltage source inverter (CC VSI) with a dc bus capacitor is used as an active power filter. The first step is to calculate SAPF reference currents from the sensed nonlinear load currents by applying the synchronous detection method and then the reference currents are fed to the proposed controller for generation of switching signals. The nonlinear load consists of one three-phase and one single-phase diode rectifier feeding R–L load, so that the effectiveness of the two-level HCC scheme to compensate for unbalanced nonlinear load can be tested. Various simulation results are presented to verify the good behavior of the SAPF with proposed two levels HCC.

Decoupled Electronic Load Controller for Offgrid Induction Generators in Small Hydro Power Generation

The control of voltage and frequency is one of the prime concerns in small off-grid hydroelectric power plants located in remote and inaccessible places. Induction generators are prime contenders for such applications which are robust, require less maintenance and have low cost. This paper deals with an implementation of a decoupled electronic load controller (DELC) for a three-phase induction generator (IG) system in standalone applications. The DELC is a combination of a static synchronous compensator (STATCOM) and conventional electronic load controller (ELC). The STATCOM consists of three-phase insulated gate bipolar transistor (IGBT) based current controlled voltage source converter (CC-VSC) with a dc bus capacitor and an ELC consists of an IGBT based chopper and an auxiliary load on the dc bus of the diode bridge rectifier. An Icos? based control algorithm is used in DELC to regulate terminal voltage and frequency, suppress harmonics and to provide load balancing. Test results are presented under balanced/unbalanced nonlinear loads to demonstrate the effectiveness of the DELC for an induction generator system.

High-speed electro-thermal modelling of a three-phase insulated gate bipolar transistor inverter power module

In this article, a high-speed electro-thermal (ET) modelling strategy to predict the junction temperature of insulated gate bipolar transistor (IGBT) devices of a three-phase inverter power module is presented. The temperature-dependent power loss characteristics of IGBT and diode devices are measured and stored in lookup tables, which replace the conventional complicated physics-based compact models. An inverter is modelled as a voltage controlled voltage source, which allows the inverter-based power train simulation to be carried out in the continuous time domain with a large simulation time-step (1 ms). Using the simulated sinusoidal voltage and current components of the inverter output, the given pulse width modulation mode, the conduction time (duty ratio) and the current of the devices are extracted. Based on the lookup tables, on-times and conduction currents of devices, the average power loss over each simulation time-step is calculated, which is then fed into the inverter thermal model to predict the devices' temperatures. The advantage of the proposed model is that an accurate ET simulation of inverter for long real-time (many minutes) operation can be carried out within an acceptable computational time using a standard modern personal computer. Both simulation and experimental validation have been carried out, and an excellent agreement has been achieved between the simulation and experimental data.

Voltage and current unbalance compensation using a static var compensator

A three-phase insulated gate bipolar transistor (IGBT)-based static var compensator (STATCOM) is used for voltage and/or current unbalance compensation. An instantaneous power theory is adopted for real-time calculation and control. Three control schemes – current control, voltage control and integrated control – are proposed to compensate the unbalance of current, voltage or both. The compensation results of the different control schemes in unbalance cases (load current unbalance or voltage unbalance) are compared and analysed. The simulation and experimental results show that the control schemes can compensate the unbalance in load current or in the voltage source. Different compensation objectives can be achieved, that is, balanced and unity power factor source current, balanced and regulated voltage or both, by choosing appropriate control schemes.

A Voltage and Frequency Controller for Self-Excited Induction Generators

This article describes a controller for voltage and frequency control of self-excited induction generator (SEIG) supplying static/dynamic, balanced/unbalanced loads. The controller is a combination of a three-phase insulated gate bipolar transistor (IGBT) based current controlled voltage source inverter (CC-VSI) and a high frequency DC chopper, which keeps the generated voltage and frequency constant in spite of change in consumer loads. A mathematical model of the SEIG with this controller supplying different types of loads is developed for predicting the behavior of the system under transient and dynamic conditions. The simulated results show that generated frequency and voltage remain constant with change in load. The proposed controller acts as reactive power compensator, harmonic eliminator, load balancer, and frequency and voltage regulator.

DSTATCOM for power quality improvement in a four-wire electric distribution system

This paper deals with the simulation of a Distribution Static Compensator (DSTATCOM) for power quality improvement in a four-wire electric distribution system. A three-phase Insulated Gate Bipolar Transistor (IGBT)-based Current-Controlled Voltage Source Inverter (CC-VSI) with a DC bus capacitor is used as a DSTATCOM. The DSTATCOM improves the supply power factor, eliminates harmonics, provides load balancing and improves the load terminal voltage at the Point of Common Coupling (PCC). The DC bus voltage of the DSTATCOM and three-phase voltages at PCC are used as feedback signals for PI controllers. The control algorithm of the DSTATCOM provides three-phase reference supply currents. A carrierless hysteresis current controller is employed over the reference and sensed supply currents to generate gating pulses for the IGBTs of DSTATCOM. Simulation is carried out in the MATLAB environment using Simulink and Power System (PSB) toolboxes. Results are presented and discussed, which demonstrate power quality improvement capability of DSTATCOM system.

Modelling of DSTATCOM for distribution system

This paper deals with the simulation of distribution static synchronous compensator (DSTATCOM) for improving power quality of a distribution system feeding linear as well as non-linear loads. Nowadays, there are an increasing number of non-linear loads which inject harmonics into the system. A three-phase insulated gate bipolar transistor- (IGBT-) based current controlled voltage source inverter with a DC bus capacitor known as a DSTATCOM is used for power factor correction, harmonic compensation and for providing required reactive power to the load. A model of DSTATCOM connected to a power distribution system feeding linear and non-linear loads (diode bridge rectifier with R and R-C) is developed for predicting the behaviour of system under transient conditions. Simulation is carried out in standard MATLAB environment using Simulink and power system blockset toolboxes. Control algorithm is made flexible so that it can correct supply power factor, eliminate harmonics and provide load balancing. The control algorithm utilises one closed loop PI controller for regulating the DC link voltage of DSTATCOM and second PI controller for regulating the AC voltage at point of common coupling. Results are presented for a variety of linear and non-linear balanced as well as unbalanced loads, which demonstrate power factor correction, voltage regulation, harmonic elimination and load balancing capabilities of DSTATCOM.

An improved control algorithm of shunt active filter for voltage regulation, harmonic elimination, power-factor correction, and balancing of nonlinear loads

This paper deals with an implementation of a new control algorithm for a three-phase shunt active filter to regulate load terminal voltage, eliminate harmonics, correct supply power-factor, and balance the nonlinear unbalanced loads. A three-phase insulated gate bipolar transistor (IGBT) based current controlled voltage source inverter (CC-VSI) with a DC bus capacitor is used as an active filter (AF). The control algorithm of the AF uses two closed loop PI controllers. The DC bus voltage of the AF and three-phase supply voltages are used as feedback signals in the PI controllers. The control algorithm of the AF provides three-phase reference supply currents. A carrier wave pulse width modulation (PWM) current controller is employed over the reference and sensed supply currents to generate gating pulses of IGBTs of the AF. Test results are presented and discussed to demonstrate the voltage regulation, harmonic elimination, power-factor correction and load balancing capabilities of the AF system.

Integrated active rectifier and power quality compensator with reduced current measurement

This paper describes a three-phase integrated active rectifier and shunt power quality compensator (IPQC). The measurement of only three currents is required, and the control algorithm can be implemented using a low-cost controller. The IPQC improves the harmonic content of the supply current, displacement power factor, supply current balance, and can serve as a four-quadrant active rectifier for motor drives and other DC-link loads. The operation of the IPQC is experimentally verified using a conventional three-phase insulated gate bipolar transistor voltage-source inverter. A low-cost fixed-point DSP-based controller with fixed-band hysteresis current regulation is used for the implementation of the control algorithms.

UPFC using multiconverter operated by phase-shifted triangle carrier SPWM strategy

The acronym UPFC covers Ggugyi's unified power flow controller and Akagi and Fujita's unified power flow conditioner. This paper describes one method of meeting high MVA specifications by using multiple modules of two-level three-phase power converter modules controlled by the phase-shifted triangle carrier technique of the sinusoidal pulsewidth modulation (SPWM) strategy. Two conceptual designs are presented. The first is the gate-turn-off (GTO)-SPWM-UPFC at the lowest switching rate, f/sub c//f/sub m/=3, to minimize GTO switching loss. The design is based on applying the fundamentals of SPWM theory to overcome unbalances arising from sideband harmonic interferences. The second is the insulated gate bipolar transistor (IGBT)-SPWM-UPFC, at f/sub c//f/sub m/=12 or higher, in which SPWM theory assures that direct paralleling of the modules is free of current unbalance. A laboratory UPFC based on six modules of three-phase 5-kVA size IGBT power converters operating at the baseline condition of dual unity displacement factor at the sending end and the receiving end has been implemented.