Field-oriented Induction Motor Research Articles

Inherently Robust Loss Model Controller for Energy Efficient Operation of Indirect Rotor Field Oriented Induction Motor Drives

Inherently Robust Loss Model Controller for Energy Efficient Operation of Indirect Rotor Field Oriented Induction Motor Drives

Dynamic Addition of Common Mode Voltage in Post Fault Operation of Cascaded H-Bridge Converter Fed Induction Motor Drive

In this article, a postfault control technique is proposed for a rotor field-oriented induction motor (RFO-IM) drive fed from a cascaded H-bridge multilevel (CHB-ML) converter. The control strategy is to vary the magnitude and phase shift of the injected fundamental common mode voltage (FCMV) according to the motor’s operating condition. The addition of the proposed FCMV with the reference phase voltages, not only ensures maximum line voltage in the postfault operating condition but also shares equal power among the remaining healthy cells of the converter. Moreover, in the postfault operation, a detailed analysis is performed on both motor and converter, and an integrated control is presented to maintain the command speed and load torque of the RFO-IM. This includes the mathematical equation explaining the new operating point of the motor for different fault configurations, traversal of operating point, and the variation in power factor of each leg of the converter in postfault conditions. From the above analysis, the dynamic FCMV is calculated from the new operating point of the stator current components in the current <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dq</i> -plane and the fault configuration of the CHB-ML converter. The proposed control technique is validated using simulation and experimental results conducted on a 3-hp IM.

Multiple Fault Tolerant Control Strategy for Rotor Field Oriented Induction Motor Drive Fed From CHB Converter With Redundant Cells

The article proposes a postfault control strategy for a rotor field oriented induction motor (RFO-IM) drive fed by a cascaded H-bridge multilevel converter (CHB-MLC) with redundant cells in each phase. The objective of the control strategy is to maintain the torque and speed of the RFO-IM in postfault operation and to maximize the converter's power capability by adding a maximum number of power cells during postfault operation. Furthermore, maximum line voltage is utilized from the redundant cells without increasing the dc-link voltage of power cells, and the motor's operating point in the voltage plane is analyzed and determined for various loading conditions during prefault and postfault operation. In the postfault operation, a common mode voltage of fundamental frequency is also added depending on the motor's loading condition and postfault configuration to distribute power evenly among the remaining healthy cells. Theoretical and graphical analyses include the equation of the operating point in the voltage plane, traversal of the operating point from prefault to postfault operation, and selection of common mode voltage of fundamental frequency based on the fault configuration and the motor's loading. The simulation and experimental data are used to validate the proposed fault-tolerant control approach.

Comparative analysis of different FOPI approximations and number of terms used on simulations of a battery-powered, field-oriented induction motor based electric vehicle traction system

Because of their enhanced performance, the fractional order proportional-integral (FOPI) controllers are becoming an appealing choice for controlling induction motor speed. To implement FOPI controllers, several fractional order integral approximations are available in the literature. The approximation used, and the order of approximation affects the speed tracking, transient response, and induction motor power consumption. This further affects the energy consumption analysis if simulations are conducted based on such approximations. In this paper an electric vehicle (EV) traction system is simulated to investigate the effect of such approximations on the simulations of a battery powered, induction motor driven EV system. The system consists of an indirect field-oriented induction motor, a lithium-ion battery bank, and a three-phase inverter. This work presents a quantitative analysis of the performance of FOPI controllers using different approximations, and order of approximations is presented. The controllers are evaluated based on speed tracking, transient response, computational time, and power consumption. Both step functions and standard drive cycles are used as the speed reference signal to evaluate the effects of using different approximations and different orders of approximation, when different references are used. This work establishes a reference set of simulations that can be used to infer the amount of error in battery state of charge, and state of health analysis conducted on such an EV system, when dealing with FOPI controllers under different approximations and related settings.

Battery Energy Management Techniques for an Electric Vehicle Traction System

This paper presents two battery energy management (BEM) techniques for an electric vehicle (EV) traction system which incorporates an indirect field-oriented (IFO) induction motor (IM) drive system. The main objective of the proposed BEM techniques is to regulate the IM&#x2019;s speed while minimizing the lithium-ion (Li-ion) battery bank state of charge (SOC) reduction and state of health (SOH) degradation. In contrast to most of the existing work, the proposed BEM techniques operate without any prior knowledge of driving profiles or road information. The first BEM technique incorporates two cascaded fuzzy logic controllers (CSFLC). In CSFLC, the first fuzzy logic controller (FLC) generates the reference current signal for regulating the motor speed, while the second FLC generates a variable gain that limits the current signal variation based on the battery SOC. The second BEM technique is based on model predictive control (MPC) which generates the current signal for the speed regulation. However, this work introduces a new way of tuning the MPC input weight using battery information. It features a fuzzy tuned model predictive controller (FMPC), where an FLC adjusts the input weight in the MPC objective function such that the battery SOC is considered while generating the command current signal. Furthermore, this work utilizes a model-in-loop strategy comprising a Chen and Mora (CM) battery model and the experimentally obtained battery bank power consumption to estimate the increase in battery bank runtime and lifetime. A real-time implementation is carried out on a prototype EV traction system using the New European Drive Cycle (NEDC) and the Supplemental Federal Test Procedure (US06) drive cycles. The experimental results validate that the proposed CSFLC and FMPC BEM techniques exhibit a lower reduction in the battery SOC and SOH degradation, thus prolonging the battery bank runtime and lifetime as compared to the conventional FLC and MPC speed regulators. Further experimentation demonstrates the superiority of the FMPC technique over the CSFLC technique due to the lesser computational burden and higher average energy saving.

Reconfigurable Control of PWM AC-DC-DC Converter without Redundancy Leg Supplying an AC Motor Drive

The purpose of this paper is the study by simulation of a fault tolerant control with Pulse Width Modulation (PWM) AC-DC-AC converter supplying a three-phase rotor field oriented induction motor. The back to back converter, is supplied with three-phase network and composed of a PWM rectifier and a voltage source inverter. Fault tolerant topology of AC-DC-AC converter that without redundancy have been studied and associated with affective and fast method of fault detection and compensation to guarantee the continuity of service, in the presence of a possible open circuit failure on the level of one of their legs. Although of the presence of open circuit on the level of one of the converter legs the control based on the Zero Sequence Signal (ZSS) assure the service continuity, the simulation results obtained prove that it is possible to maintain the good performance of the drive without redundancy leg (6/5 topology).

A Wind Turbine Emulator Using Field-Oriented Induction Motor

This paper proposes a Wind Turbine Emulator (WTE) using an Indirect Field Oriented (IFO) Induction Motor (IM). The IM drive can be controlled as a conventional prime mover in speed mode, or a wind turbine in torque-speed mode via robust observed torque control. This paper presents key issues for establishing a high-performance IFO IM drive. Further, this study develops a wind turbine load Interior Permanent-Magnet Synchronous Generator (IPMSG) followed by a three-phase Vienna Switch-Mode Rectifier (SMR). It receives mechanical driven power from the WTE and establishes a 400V DC-link for the DC micro-grid. The good generating characteristics are achieved through proper controls of both the IPMSG and SMR. Various wind turbine torque-speed and power-speed characteristic curves under different wind speeds can be emulated by the developed WTE. The designed results are verified by simulations. The measured results indicate that the errors are within 1.5% and 1.0%, respectively, for the torque and the power compared to the designed ones. The maximum power point tracking (MPPT) function with good performance for the PMSG with Vienna SMR is achieved using the perturb and observation (P&amp;O) approach. The dynamic and steady-state operating characteristics of the developed whole turbine emulator driven PMSG system are assessed experimentally.

Artificial neural network-based current control of field oriented controlled induction motor drive

A hysteresis current controller (HCC) is commonly used in high-performance AC motor drives to control the current directly. Recently, the predictive current controller (PCC) is also used as an alternative to the classical current controller for speed and torque regulation of induction motor (IM) drives. However, PCC has drawbacks of large flux and torque ripples, large total harmonic distortions (THDs) in current and voltage and dependency on parameters. This paper proposes current control with artificial neural network (ANN) for a field-oriented controlled induction motor (FOCIM) drive. The ANN has input current error between the reference and the measured stator currents. The output function of neuron is a hyperbolic tan (or tan-sigmoid) function to apply error Levenberg–Marquardt (L–M) back propagation as learning rule because of its fast convergence. The proposed method is based on a new approach in which hysteresis band is replaced by ANN comparator to improve the performance of the FOCIM drive. It minimizes torque ripples, flux ripples, voltage and current THDs over the existing HCC and PCC methods. The superiority of the proposed method compared to existing methods is established by simulation and experimental results.

Evaluation of the High Performance Indirect Field Oriented Controlled Dual Induction Motor Drive Fed by a Single Inverter using Type-2 Fuzzy Logic Control

In this paper, a high-performance indirect field-oriented controlled dual Induction Motor (IM) drive fed by a single inverter using type-2 fuzzy logic control will be presented. At first, the mathematical model of the IM is implemented in the d-q reference frame. Then, the speed control of the Dual Induction Motor (DIM) operating in parallel configuration with Indirect Field Oriented Control (IFOC) using PI and type-2 Fuzzy Logic Controller (T2-FLC) will be presented. For the control of this system, a DC supply and a Space Vector Pulse Width Modulation (SVPWM) voltage source inverter are introduced with constant switching frequency. Also, the performance of T2-FLC, which is based on the IFOC, is tested and compared to those achieved using the PI controller. The simulation results demonstrate that the T2-FLC is more robust, efficient, and has superior dynamic performance for traction system applications.

Current Prediction-Based Three-Vector Voltage Optimization System for the Induction Motor with Current Static Error Correction

In the present study, the current control method of the model predictive control is applied to the field-oriented control induction motor. The augmentation model of the motor is initially established based on the stator current equation, which performs the current predictive control and formulates the new cost function by means of tracking error. Then, the influence of parameter error on the current control stability in the prediction model is analysed, and the current static error is corrected according to the correlation between the input and feedback. Finally, a simple and effective three-vector control strategy is proposed. Moreover, three adjacent basic voltage vectors are utilized, and then six candidate voltage vectors are synthesized in each sector to replace eight basic voltage vectors in the conventional model predictive control (MPC). The obtained results show that synthesized vectors, which have arbitrary amplitude and direction, significantly expand the coverage of the system’s control set, reduce the torque and flux pulsation in the conventional MPC, and improve the steady-state performance of the system. Finally, the dSPACE platform is employed to validate the performed experiment. It is concluded that the proposed method can reduce the torque and flux pulse, perform the induction motor current control, and improve the steady-state performance of the system.

Experiment based comparative analysis of stator current controllers using predictive current control and proportional integral control for induction motors

The stator current control loop plays an important role in ensuring the quality of electric drives interm of producing fast and adequate required torque. When the current controller provides ideal responses, speed control design subsequently is in charge of improving the system performances. Classical PID control is commonly used in current loop design, this paper presents the comparative analysis of current stator controller using proportional integral control and predictive current control (PCC) in field-oriented control-based induction motor drives, with rigidly coupled loads. The experimental results show system responses with PID and PCC. Informative experiment-based analysis provides primary guidance in selection between the two controls.

Control of Rotor Field-Oriented Induction Motor Drive During Input Supply Voltage Sag

This article proposes a speed control strategy for rotor field-oriented induction motor (RFO-IM) drive during input supply voltage sag (VS). The purpose of this control technique is to maintain the torque and speed constant during VS condition. In the control technique, reference d-axis and q-axis current commands are obtained by solving the voltage, current, and torque constraints in the current plane. In the event of VS beyond a limit, the control is made such that the motor delivers the load torque with reduced speed. Traversal of operating points of the motor during input supply VS for constant load torque and rated reference speed are analyzed, and the limit of reduction in d-axis current reference is also obtained. Mathematical equations explaining the current trajectory to be followed during VS, VS limit, and the settling speed are derived. The proposed control is simulated in MATLAB/Simulink and experimental validation is conducted on a 3-hp IM.

Nonlinear flux observer-based feedback linearisation control of IM drives with ANN speed and flux controller

ABSTRACT In this paper, ANN speed and flux controller for feedback linearisation control (FLC) IM drive with nonlinear flux observers are proposed to achieve an accurate and fast dynamic response over a wide operating range. Because of the nonlinearity in IM, a linear PI controller with direct field oriented control (DFOC) IM drive, gives the poor performance, longer convergence time and limited disturbance capability. Therefore, a nonlinear flux observer is developed for intelligent FLC using a modified LPF to reduce the dc offset, which minimises torque ripple, flux ripple and also reduces current THDs. Dynamic performances are simulated in MATLAB/Simulink environment and simulation results are validated experimentally. A relative comparative analysis is also carried out between classical field-oriented controlled induction motor drive and the proposed method. From the results obtained, it is observed that the proposed method is superior to FOC IM drive in terms of fast dynamic response, better speed tracking dynamics and reduction of, current THDs, torque and flux ripples.

Performance enhancement of electric vehicle traction system using FO‐PI controller

This work improves the performance of an electric vehicle (EV) traction system by using non-linear fractional-order proportional–integral (FO-PI) controller. The functionality of FO-PI controller is benchmarked against integer-order proportional–integral (IO-PI) controller. A 400 V, 6.6 Ah Li-ion battery bank is designed to power an indirect field-oriented induction motor driven prototype EV traction system. The appeal of this study is to reveal the simplicity, robustness, and effectiveness of FO-PI speed regulator for EV traction system. The efficacy of FO-PI speed regulator for EV applications is validated through rigorous experimentation. The FO-PI controller due to its non-linear nature proves to be more robust and effective under variation of a system's parameters and external disturbances as compared to IO-PI controller. Furthermore, the experimental results show that FO-PI control strategy provides higher torque per amp output while maintaining better voltage and state-of-charge profiles of the Li-ion battery bank.

MRAS-Based Speed Estimation of Induction Motor Drive Utilizing Machines' d- and q-Circuit Impedances

This paper proposes a new model reference adaptive system (MRAS) for the sensorless speed estimation of field-oriented induction motor (IM) drive utilizing d - and q -circuits effective impedances. The functional quantity of the MRAS, in this context, is the difference between the stator d - and q -circuits' effective working impedances. This unique structure does not require any flux computation while estimating speed. Moreover, the formulation is free from any resistance terms. The proposed estimator performs satisfactorily at all the operating points and exhibits stability in all the four quadrants of the drive's operation. The relevant stability and sensitivity studies, in this regard, are done in MATLAB/Simulink. Furthermore, the controller performance is validated experimentally by dSPACE-1103-based IM drive setup.

Fast detection control for fault-tolerant converter back-to-back with redundancy leg supplying an induction motor drives

The purpose of this paper is the study of fault tolerant control with pulse large modulation (PWM) AC-DC-AC converter for supplying a three-phase rotor field oriented induction motor. The back to back converter is supplied with three-phase network and composed of a PWM rectifier and a voltage source inverter. Fault tolerant topology of AC-DC-AC converter with redundancy have been studied and associated with affective and fast method of fault detection and compensation to guarantee the continuity of service, in the presence of an open circuit failure possibility on the level of one of their legs. Although of the presence of open circuit on the level of the converter legs, the obtained simulation results show that the proposed method has the ability to maintain the good performance of the drive.

A Novel Online Parameter Estimation Method for Indirect Field Oriented Induction Motor Drives

This paper presents a novel online parameter estimation method to overcome the negative influence of parameter mismatch on the field orientation and then on the performance of the indirect field oriented induction motor drives. This method allows for parallel estimation of the rotor resistance and the mutual inductance, which tend to deviate from their nominal values resulting from changes in temperature and flux level. In the case of electrical vehicles or wind power generators, the parameter deviation degrades the drive performance in two ways: calculation of the current reference from the torque command issued by the power control unit and calculation of the slip frequency for the indirect field orientation. Moreover, the mutual inductance estimation is more critical in these wide speed range applications than in general industry field. This proposed estimation method is implemented through a model reference adaptive system about the rotor flux. The reference model comes from two sliding-mode observers (SMOs): a terminal SMO and a linear SMO, implemented in series. The adjustable model is undertaken by the current model of rotor flux. The analysis and design presented in this paper are confirmed both through numerical simulation and experiments.

Modeling, simulation and re-adhesion control of an induction motor–based railway electric traction system

Increasing the traction force is a complex problem in the design of railway vehicles; therefore, effective traction systems and algorithms have to be developed. During the traction process, the verification of traction algorithms and control strategies are based on simulations covering all locomotive dynamics. In this article, traction model of a railway vehicle and re-adhesion control method based on simulation approach are investigated to obtain more effective results. The longitudinal dynamic of a railway vehicle having traction system, which comprises two parallel motor groups, each of which has two field-oriented induction motor connected in series, is simulated to examine time-dependent changes in motor stator currents, traction torque, adhesion and resistance forces according to a given speed reference. The interaction between the adhesion force and the slip ratio is established according to the Burckhardt adhesion model, and a modified super-twisting sliding mode slip control is implemented in a computer simulation under various contact conditions so that simulation results approve the presented control method works under the maximum adhesion force. The comparison between the classical and modified version of the proposed control strategy was made to better evaluate the performance of the control system and to better optimize the traction system.

A Self-Healing Induction Motor Drive With Model Free Sensor Tampering and Sensor Fault Detection, Isolation, and Compensation

This paper introduces new schemes for detection, isolation, and compensation of speed and current sensor (CS) faults in field oriented induction motor (IM) drives. These schemes do not use any kind of machine model and motor parameters. This is a prominent feature of the proposed approaches, which only rely on main concepts of field-oriented control (FOC)-based IM drives. Moreover, the proposed fault detection and isolation (FDI) schemes can take partial sensor failures into account. These kinds of faults that might be caused by mechanical or electrical failures, or intentional sensor tampering, are difficult to be dealt with since embedded speed and current control loops react swiftly, and inherently try to camouflage partial sensor failures. CS faults result in imbalance current flow in the motor stator phases, and speed sensor fault repudiates the orthogonally alignment of field and torque current components in field oriented IM drives. These features are cornerstones of introduced FDI methodology. Furthermore, model and parameter free compensators are proposed to recover normal operation of the machine before fault incident. After in-depth analysis, extensive simulation and experimental tests validate the proposed schemes.

RISE-backstepping-based robust control design for induction motor drives

PurposeThis paper aims to address the speed and flux tracking problem of an induction motor (IM) drive that propels an electric vehicle (EV). A new continuous control law is developed for an IM drive by using the backstepping design associated with the Robust Integral Sign of the Error (RISE) technique.Design/methodology/approachFirst, the rotor field-oriented IM dynamic model is derived. Then, a RISE-backstepping approach is proposed to compensate for the load torque disturbance under the assumptions that the disturbances are C2 class functions with bounded time derivatives.FindingsThe numerical validation results have presented good control performances in terms of speed and flux reference tracking. It is also robust against load disturbances rejection and IM parameters variation compared to the conventional Field-Oriented Control design. Besides, the asymptotic stability and the boundedness of the closed-loop signals is guaranteed in the context of Lyapunov.Originality/valueA very relevant strategy based on a conjunction of the backstepping design with the RISE technique is proposed for an IM drive. The approach remains simple and can be scaled to different applications.