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The primary objective of this work is to optimize the induction motor rotor flux so that maximum efficiency is attained in the facets of parameter and load variations. The conventional approaches based on loss model are sensitive to modelling accuracy and parameter variations. The problem is further aggravated due to nonlinear motor parameters in different speed regions. Therefore, this work introduces an adaptive neuro-fuzzy inference system-based rotor flux estimator for electric vehicle. The proposed estimator is an amalgamation of fuzzy inference system and artificial neural network, in which fuzzy inference system is designed using artificial neural network. The training data for neuro-fuzzy estimator is generated offline by acquiring rotor flux for different values of torque. The conventional fuzzy logic and differential calculation methods are also developed for comparative analysis. The efficacy of developed system is established by analyzing it under varying load conditions. It is revealed from the results that suggested methodology provides an improved efficiency i.e. 94.51% in comparison to 82.68% for constant flux operation.

This paper presents the comparative studies of two permanent magnet (PM) motors, which are modular-stator outer-rotor flux-switching permanent-magnet (MSOR-FSPM) motor and conventional outer-rotor flux-switching permanent-magnet (COR-FSPM) motor. The differences in structure and design principles between the two types are compared. Then, a 2D finite element method (FEM) is used to analyze the basic electromagnetic performances. The magnetic field distribution, no-load back-EMF, cogging torque, and electromagnetic torque are presented and compared. Furthermore, a comprehensive comparison of the motor performances which are important for electric vehicles is investigated. The theoretical analysis and FEM results predict that the MSOR-FSPM motor has superior capability compared to that of the COR-FSPM motor, including fault tolerance capability, and field weakening capability.

A robust predictive current control algorithm for permanent magnet synchronous motor (PMSM) drives is proposed. The robust controller adopts an incremental system model, thus can operate without knowing the rotor flux, which is a pivotal parameter in conventional dead-beat control. The incremental model is easy to implement compared with relevant flux identification algorithms or observers. The robust controller adopts an extended state observer (ESO) to enhance inductance robustness to cater for the divergence caused by stator inductance mismatch. The inductance mismatch uncertainties can be estimated and compensated by ESO. Conventional dead-beat control is modified for multistep prediction to achieve high disturbance rejection. Detailed stability and disturbance rejection analysis are conducted theoretically, and rules on parameter selection are given. Comparative simulations and experimentations verify the effectiveness and superiority of proposed robust control over conventional dead-beat control.

Because of many advantages of a direct-driven permanent magnet synchronous generator (PMSG), it becomes one of the most attractive variable speed wind energy generation type. Different control strategies have been studied for controlling the machine side converter of the PMSG. This paper presents a comparative study of three current control schemes for machine side converter (MSC) based on rotor flux oriented control. Firstly, an integral sliding mode controller (ISMC) is designed to regulate the stator current in the synchronous reference frame. The proposed ISMC has two integral switching functions for stator direct and quadrature currents control. Secondly, a finite control set model predictive control (FCS-MPC) is designed to regulate the stator current and replace ISMC. The proposed MPC takes the discrete states of the voltage source inverter into account and the future converter behavior is predicted for each sampling period. Then the switching action that minimizes a predefined cost function is selected to be applied in the next sampling instant. Neither axes transformation nor modulation technique of the stator voltage is required. Finally, to evaluate the performance of the proposed controllers, their performance is compared to the conventional PI-controller under the same operating conditions. The feasibility and effectiveness of the proposed schemes have been demonstrated through computer simulations. The results show the advantages and drawbacks of each controller.

This paper proposes how to use the addition of rotor position offsets as perturbation signals for the parameter estimation of permanent-magnet synchronous machines (PMSMs), which can be used for the condition monitoring of rotor permanent magnet and stator winding. During the proposed estimation, two small position offsets are intentionally added into the drive system, and the resulting voltage variation will be recorded for the estimation of rotor flux linkage. With the aid from estimated rotor flux linkage, the stator winding resistance can be subsequently estimated at steady state. This method is experimentally verified on two prototype PMSMs (150 W and 3 kW, respectively) and shows good performance in monitoring the variation of rotor flux linkage and winding resistance.

This paper presents the design and implementation of a current controlled Rotor Flux Oriented PMSM for automotive steer-by-wire applications. The development of a realistic torque feedback reference is carried out by actual monitoring of a commercial vehicle. The paper shall discuss the torque dynamics of the PMSM drive with respect to position demands replicating a driver at the handwheel. A PowerPoint presentation by same authors about this subject is included in this section., peer-reviewed

This paper analyzes the dynamic performance of FOC induction machines operating under current and voltage constraints. FOC rely on the proper performance of the inner current control loops. The capability of the machine to increase its torque can be seriously compromised due to the inverter voltage and current limits, which affect to the current regulator transient response. This can be especially critical in machines controlled to operate with reduced rotor flux to increase their efficiency.

This paper presents a robust predictive current (RPC) control method for permanent magnet synchronous motor (PMSM). The RPC controller adopts an incremental model, thus the influence of rotor flux can be omitted. This is the main contribution of RPC controller. Moreover, an inductance observer based on Lyapunov stability theorem is adopted to enhance inductance robustness against stator inductance mismatch. Detailed design process and limitations of currents and voltages are presented. The effectiveness and superiority of RPC over dead-beat predictive method are verified through comparative simulative results.

This paper presents a novel algorithm for speed and position estimation of Permanent Magnet Synchronous Machine (PMSM). The developed sensorless control scheme is based on a simple implementation of sliding mode observer (SMO) employing the modified PMSM mathematical model. All PMSM variables are expressed in an arbitrary rotating frame. Initially the modified rotor flux is calculated through measuring the stator voltages and currents. Then the required rotor speed and angle are estimated via a connected in series SMO using the modified rotor flux as input. Simulation results demonstrate and the effectiveness of the proposed sensorless method and the convergence performance of rotor speed/angle observer.

To improve the dynamic control performance of bearingless induction motor (BLIM), the active disturbance rejection control strategy is presented. Based on the rotor flux orientation inverse decoupling strategy, an active disturbances rejection control (ADRC) system is designed to replace the PID control system. The cross coupling items, motor parameter change and load are all regarded as disturbance. The total disturbance is estimated by an extended state observer (ESO), and compensated by a nonlinear state error feedback (NLSEF) controller. Simulation results show that the system has better dynamic decoupling performance and strong robustness.

The induction machine has proved to be an appropriate solution for most industrial applications; Moreover, it presents the future of sustainable automotive industry due to the strategies of control and command of which it can be equipped. This paper presents a study of advanced methods applied to the control of induction machine in order to obtain a system satisfying the criterion of robustness. This work has been done as a comparison between the conventional controller and the advanced techniques of control such as fuzzy logic and artificial neural network. The results of various simulation tests highlight the robustness properties of the different control strategies based on orientation of the rotor flux.

This paper presents a method for evaluating, both qualitatively and quantitatively, the effects of specific rotor design parameters on the performance of a Synchronous Reluctance Machine (SynRM). The method uses multi-factor experimental design, with Analysis of Variance (ANOVA), and Finite Element Analysis (FEA) to determine the optimal rotor design parameter according to a specific objective. Using this method, two factors — rotor flux barrier pitch angle and barrier width — are selected at simultaneously varied levels for assessment with the aim of analyzing the response variables, which are, the average torque and torque ripple. Results from the investigation show that the influence of the rotor flux barrier pitch angle on the torque ripple is more statistically significant than the influence of the barrier width. However, the effect of the barrier width on the average torque is more significant.

The induction motor system is dynamically formulated by both the mechanical and electrical equations. In system identification of an induction motor, main objective is to compare parameters between identified by using rotating speed and that by both rotating speed and robust observer. The real-coded genetic algorithm (RGA) is adopted to identify all parameters, and the reduced-order robust observer is used to reconstruct the non-measurable state variables, for examples, the stator current and rotor flux. From numerical simulations and experimental results, it is found that the robust observer association with RGA can be used to identify the non-measurable state variables for an induction motor.

Flux-switching permanent magnet (FSPM) motors have gained increasing attention in the electric vehicles (EVs) applications due to the advantages of high power density, high efficiency. However, the heat sources of both permanent magnet (PM) and armature winding are located on the limited stator space in the FSPM motors, which may result in the PM overheated and irreversible demagnetization caused by temperature rise and it is often ignored in the conventional thermal analysis. In this paper, a new electrical-thermal two-way coupling design method is proposed to analyze the electromagnetic performances, where the change of PM material characteristics under different temperatures is taken into consideration. Firstly, the motor topology and design equations are introduced. Secondly, the demagnetization curves of PM materials under different temperatures are modeled due to PM materials are sensitive to the temperature. And based on the electrical-thermal two-way coupling method, the motor performances are evaluated in details, such as the load PM flux linkage and output torque. Then, the motor is optimized, and the electromagnetic performances between initial and improved motors are compared. Finally, a prototype motor is manufactured, and the results are validated by experimental measurements.

This paper focuses on speed and current sensor fault detection and isolation (FDI) for induction motor (IM) drives. A new, accurate and high-efficiency FDI approach is proposed so that a system can continue operating with good performance even in the presence of speed sensor faults, current sensor faults or both. The proposed three paralleled adaptive observers are capable of current sensor fault detection and localization. By using observers, the rotor flux and rotor speed can be estimated which allows the system to run under the speed sensorless vector control mode when a speed sensor fault occurs. In order to detect speed sensor faults, a threshold-based scheme is proposed. To verify the feasibility and effectiveness of the proposed FDI strategy, experiments are carried out under different conditions based on a dSPACE DS1104 induction motor drive platform.

In this paper, the real time implementation of the speed sensorless vector control of induction motor (IM) drive based on full-order observer is presented. To decrease the associated maintenance costs, adaptive full-order observer is used to estimate the rotor speed. The adaptive full-order observer based on IM equations is used to estimate stator currents and rotor flux. The speed is estimated depends on the error between the actual and estimated stator currents. However, the performance of this scheme deteriorates when approaching the zero speed zones because the effect of the variation of the stator resistance and the problem of the stability. The stator resistance has been estimated in parallel with the rotor speed to compensate the error in estimated rotor speed in the low speed region. Lyapunov’s stability criterion is employed to estimate rotor speed and stator resistance. This paper presents an experimental evaluation of the performance of speed observer when working at very low. Synthesis of the controller has been presented. The simulations and experiments results prove excellent steady-state and dynamic performances of the drive system in a wide speed range, especially at very low speeds, which confirms validity of the proposed scheme.

Accurate acquisition of asynchronous motor rotor flux plays a significant part in the high-performance motor speed regulation system. For that reason, this paper gives the advantages and disadvantages of various methods for motor rotor flux observation based on the studying of them, also application guides are given. Finally, a combination model based on the voltage model of rotor flux observer and the current model of rotor flux observer is given, and simulation analysis based on the combination model is carried out by Matlab/Simulink to verify the effectiveness of it.

This paper deals with the design of an output feedback predictive controller for induction motors. The fundamental interest of the proposed controller is the capability of decoupling the mechanical speed and the rotor fluxes, without degradation against the variation of rotor resistance and load torque. Hence, the contribution is to apply two estimation procedures in order to achieve this goal. Namely, an unknown input observer (UIO) is used for the constant time estimation whereas a heuristic solution is exploited for the load torque update. Moreover, rotor flux components are recovered as an unavailable state of the system. Effectiveness of the proposed observers and the performance of the controller are confirmed by simulation results.

This paper reviews the model of the induction motor in stationary reference frame, with stator current and rotor flux components as state variables. The state feedback linearizing and decoupling control as applied to the induction motor drive is presented. With this control, the drive system is decoupled into two linear subsystems: electrical and mechanical. Comprehensive and systematic procedures are developed to determine the gains of the Proportional-Integral (P-I) controllers for electrical and mechanical subsystems. The controlled drive system is simulated in MATLAB SIMULINK and experimented in RTDS environment, and results are presented. 

Purpose – The aim of this paper is to present a new sensorless control strategy using a flux observer, which is particularly designed for taking into account the rotor saliency and winding inductance variation in an interior permanent magnet synchronous motor (IPMSM).Design/methodology/approach – In a PMSM, the magnets‐excited flux‐linkage, i.e. the rotor flux‐linkage, can be expressed as a vector. Its phase angle stands for the rotor position. Therefore, if this vector is estimated with an observer, the rotor position can be obtained without a position sensor, consequently, sensorless control can be realized. The main object of this paper is to establish and implement a model of rotor flux observer, specifically for IPMSM.Findings – The flux observer model is built on the d‐q‐0 frame, using unequal values of the d‐axis inductance Ld and q‐axis inductance Lq to represent the IPMSM rotor saliency. Its digital implementation is proposed, whilst the sensorless control strategy is experimentally verified.Rese...

In this article, we present the construction of observers of rotor flux and mechanical speed needed for robust control of the asynchronous machine. Two observers will be developed for comparison. The first is based on the technics MRAS and the second is observer of KUBOTA, with the enhanced DTC, “sensorless DTC”.

This paper presents an online adaline neural network (ANN) based identification method for estimating the dq-axis inductances of interior permanent magnet synchronous machine (IPMSM). This method only needs to sample the phase currents, bus voltage, rotor position angle and speed without any design parameters. In the proposed estimation, the rotor flux linkage and the stator winding resistance are firstly estimated offline, and then they are regarded as constants to estimate the dq-axis inductances online. The proposed method shows good stability when the load changes suddenly. The white noise is added to the load torque to validate the good robustness of the method. The results of online identification are acceptable even small error exists in the value of offline identification. Simulations using an IPMSM model illustrate the validity of the proposed online identification strategy.

The sliding mode observer is a very promising approach for position sensorless control of Permanent Magnet Synchronous Motors due to its robustness and parameter insensitivity. However it was observed that estimation of rotor flux position was affected due to measurement noise and phase shift introduced due to low pass filtering. In this paper, the authors discuss key issues related to implementation of sliding mode observer based sensorless field oriented control of Permanent Magnet Synchronous Motor and propose different approaches to improve rotor flux estimation. An experimental lab setup is designed and implemented on a 400W PMSM motor. Texas Instrument's TMS320F2812 DSP is used in the drive as the central controller to fulfill the demands of exhaustive real time computations by vector control and sliding mode observer.

Many existing sensorless control methods are based on flux observers, where phase-locked loops (PLLs) were used to extract the position information from the estimated rotor flux. This paper proposes an improved quadrature-component-based phase locked loop (Q-PLL) scheme for sensorless control of permanent magnet synchronous motor (PMSM) drives. To show the superiority of the proposed method in solving the problem of speed reversal, other three kinds of PLLs are also presented for the aim of comparison. This improved PLL is integrated with SMO-based sensorless control of PMSM drives. Compared to conventional Q-PLL, the main advantage of the proposed PLL is that it can work well without a gain scheduling remedial strategy or a judgment of the sign of speed in terms of speed reversal. Furthermore, it has a better performance in the transient and steady state response. Both Simulation and experimental results are presented to demonstrate the good performances of the proposed Q-PLL.

This paper presents the hypersynchronous converter cascade with intermediate DC-link scheme and one of the easiest and most reliable ways to control valves dependent on the rotary transducer rotor flux current. The equations explaining the regulation principle and the basic expression for calculating the hypersynchronous converter cascade static characteristics are presented. The design and control characteristics of static mechanical and experimental characteristics are provided.

In this paper, an analysis of the induction motor control scheme based on the Direct Rotor Flux Oriented Control (DRFOC) for a whole speed range, including field-weakening (FW) regions is presented. Two field-weakening algorithms have been compared and verified through simulation with a 3.0 [kW] induction motor drive.

Spatial orientation and magnitude of the rotor flux is essential for vector control of induction motor. Traditionally, current model serves for rotor flux estimation and rotor must be measured by speed sensor. Due to advantages of low cost and high reliability, control the induction motor without sensor draws great attention of scholars around the world. Closed-loop observers or open-loop estimators are used for such purpose. In this paper a new method of sensorless vector control of induction motor is proposed and simulation is implemented to verify the scheme.

The traction converter and control system of EMU is constructed based on Matlab/Simulink. The system consists of a transformer, a rectifier, an inverter and an induction motor. The rectifier is controlled by the transient current control theory with SPWM technology. In the inverter the indirect rotor flux oriented control theory with current hysteretic band PWM strategy is adopted. Based on the system the traction control and constant speed control are tested. The simulation results present that the system is with good dynamic and steady state performance and fulfill the running demand of EMU.

This paper deals with the feasibility on FPGA implementation of a continuous-discrete time observer applied to an induction machine (IM). With only stator currents measurement which are weakly sampled, we can achieve not only a quit reconstruction of these last signals but also, an acceptable estimation of the mechanical speed, the rotor flux components and the load torque. By comparison with its continuous version, the proposed observer presents an improvement results which are proved by numerical simulation.

Based on anglicizing characteristics of the proportional resonance controller (resonant, PR), against the defects of the PR controller, combined with permanent magnet synchronous motor mathematical model, a rotor flux oriented vector control strategy based on a novel improve the PR controller is introduced. Finally, MATLAB /simulink was used to simulate the model above. The system got good dynamic and static responses, verifying the correctness and feasibility of the proposed method.

The speed-adjustable system of asynchronous motor has been widely used in industrial production. in motor control, magnetic control is a key problem, but in order to realize the control of motor, magnetic field must be tested. The testing methods about rotor flux according to the rotor field-oriented control of motor are discussed in this paper. The paper describes the present two rotor flux calculation models: Voltage model and Current model. It concretely analyzes mathematical expressions of these two models in different coordinates, and realizes the matlab simulation of two kinds of model, the simulation results are compared by observations of the magnetic chain calculation results.

PurposeThe purpose of this paper is to obtain an accurate and robust estimation method of the rotor flux and speed for the sensorless induction motor (IM) drive with magnetizing reactance variations.Design/methodology/approachThe sensorless IM drive with sliding mode flux and speed observer (SMO) is presented. Proposed estimation algorithm is extended with the additional magnetizing reactance estimator based on the magnetizing characteristic of the IM. The dynamical and steady‐state properties of the drive system in the low‐speed and in the field‐weakening regions are tested. The simulation results are verified by experimental tests, over the wide range of motor speed and drive parameter changes.FindingsIt is shown that the sensorless induction motor drive can work stable in wide speed range using the Sliding‐Mode Observer with additional magnetizing reactance estimator.Research limitations/implicationsThe investigation looked mainly at the speed estimation methodology with additional motor parameter estimator.Practical implicationsThe proposed SMO can be easily implemented on digital signal processors. The implementation was tested in an experimental setup with DS1103 card. The fixed‐point realisation needs to be developed to obtain the practical application in the industrial drive systems.Originality/valueThe SMO with an additional magnetizing reactance estimator based on magnetizing characteristic of the IM is tested. This method of the speed and flux reconstruction can be applied in different electrical drives working in wide speed range, including very low‐speed region and field‐weakening region, too. The proposed solution is not sensitive to magnetizing reactance variations and is simple in practical implementation in the real‐time system.

This paper proposes a convex optimization approach for the design of robust observers applied to the control of five phase induction machines subject to rotor resistance variation and load disturbance. Based on the first and third harmonic dynamic models of the multi-phase machine, two robust observers are proposed to estimate the rotor flux components. The two observers are applied to the direct field oriented control of a five phase induction machine, where simulation results have demonstrated a high dynamic performance and robustness to parametric variations of the proposed setup.

The inverter non-linear effects limit the performance of Sensorless Field Oriented Control (SFOC) of Induction Motor (IM) drives. When no direct voltage measurement is available and the reference voltages are used instead, the problem relies in the non-linear error that affects the motor back-emf estimation. The back-emf signals are fundamental for estimating the motor flux in most of SFOC schemes, either oriented on the stator flux or on the rotor flux. Many methods have been proposed for compensating such non-linearities (IGBT dead-time and on-state voltage drops) by means of the digital control algorithm. In many references the compensation relies on an inverter model based on the signum function of the motor phase currents. In the considered cases, the identification of the compensation parameters is performed off-line, often with additional processing tasks. Very few schemes are integrated into the control code of the IM drive. The goal of the paper is to present a model of the inverter non-linear effects that is more accurate than the signum-based one, and the related self-identification method. The proposed inverter model can be identified directly by the digital controller at the drive start-up with no extra measures other than the motor phase currents and dc-link voltage. After the commissioning session, the compensation does not require to be tuned furthermore and is robust against temperature detuning. The identification is based on the feedback signal of the closed-loop flux observer in dc current conditions. The experimental results, presented here for a rotor flux oriented SFOC IM drive for home appliances, demonstrate the feasibility of the proposed solution.

A linearization method is proposed for controlling the start-up operation of a rotating induction motor. The dynamics of this motor are deteriorated when the starting operation is carried out at high frequencies. In this method, the characteristics of the method are analyzed to reveal that the aforementioned problem is caused by the low equivalent gain of the induced voltage during the rotor flux establishment. A method to compensate for the angle of the rotor-flux-induced voltage vector is proposed to overcome this problem. The proposed method is experimentally verified by a test set, and the influence of changes in the rotor resistance is analyzed.

Sensor less induction motor drives are widely used in industry for their reliability and flexibility. However, rotor flux and speed sensors are required for vector control of induction motor. These sensors are sources of trouble, mainly in hostile environments, and their application reduces the drive robustness. The cost of the sensors is not also negligible. All the reasons lead to development of different sensor less methods for rotor flux and mechanical speed estimation in electrical drives. The paper deals with the speed estimators for applications in sensor less induction motor drive with vector control, which are based on application of model adaptive, based sliding mode observer methods. This paper presents the development and DSP implementation of the speed estimators for applications in sensor less drives with induction motor.

This paper proposes a new model-based diagnostic technique, which is the so-called virtual current technique (VCT), for the diagnosis of rotor faults in direct rotor field oriented controlled (DRFOC) induction motor drives. By measuring the oscillations at twice the slip frequency found in the rotor flux of the machine, and by conjugating this information with the knowledge of some motor parameters, as well as the parameters of the flux and current controllers, it is possible to generate a virtual magnetizing current which, after normalization, allows the detection and quantification of the extension of the fault. The proposed method allows one to overcome the major difficulties usually found in the diagnosis of rotor faults in closed-loop drives by providing information about the condition of the machine in a way that is independent of the working conditions of the drive such as the load level, reference speed, and bandwidth of the control loops. Although the VCT was primarily developed for traction drives used in railway applications, it can be incorporated in any DRFOC drive at almost no additional cost. Several simulation results, obtained with different types of DRFOC drives, as well as experimental results obtained in the laboratory, demonstrate the effectiveness of this new diagnostic approach.

If an adaptive induction machine flux model is to be used for rotor flux space vector estimation in a vector controlled drive, the magnetizing curve of the machine has to be known. A desirable feature of the magnetizing curve identification algorithm is that the procedure should constitute a separate routine which can be executed during commissioning of the drive. An experimental procedure, which utilizes current regulated PWM inverter aimed for continuous operation of a vector controlled induction machine, is developed for this purpose. It relies on indirect vector control technique and makes use of a PC implemented indirect vector controller. Appropriate processing of data, obtained during measurements, enables identification of the magnetizing curve. To illustrate the accuracy of the algorithm, results of identification are verified by an existing method aimed for rotor time constant tuning in indirect vector controller.

Parameter variation effects infield-oriented induction machines can cause significant performance deterioration. Magnetic saturation of the main flux path is one of the sources of parameter variations, caused by non-linear nature of the magnetizing curve. The paper at first discusses operating regimes of a rotor-flux-oriented machine which lead to operation with variable main flux in the machine. These are shown to be operation with variable stator d-axis current command during forced excitation and in field-weakening region, and operation with variable q-axis current command during rapid speed changes when cross-saturation effect causes variable main flux operation. Actual effects of variable saturation level on performance of the drive are assessed by simulation. Modified rotor flux estimation schemes are then derived, which enable instantaneous open-loop adaptation to actual saturation degree in the machine. The proposed adaptive rotor-flux estimators are verified by simulation and some experimental results are included as well. As the saturated induction machine representation is based on the current state-space model, while the modified rotor-flux estimator relies on the flux state-space model, the performed simulation study shows that current state-space model and flux state-space model, although considerably different in their appearance, account for the main flux saturation in basically the same way.

PurposeThis paper seeks to discuss the implementation of the rotor flux oriented control (RFOC) in a four‐switch three‐phase inverter (FSTPI)‐fed induction motor drive.Design/methodology/approachThe implementation is achieved considering a current regulation of the FSTPI. Such a regulation is done thanks to bang‐bang regulators. As far as the FSTPI is fed by a battery pack, the paper considers an electrical equivalent circuit of such a power supply.FindingsSimulation works, carried out considering the case of an ideal model of the battery pack and the case where the electrical equivalent circuit of the battery pack is taken into account, have shown that the drive dynamic performance are practically the same. Furthermore, and in order to highlight the performance of the induction motor fed by a FSTPI, these are compared with those obtained with the induction motor fed by a conventional six‐switch three‐phase inverter (SSTPI), considering both models of the battery pack. It has been found that the drive offers almost the same dynamic and steady‐state performance.Research limitations/implicationsThe work should be extended by an experimental validation of the simulation results.Practical implicationsThe established results open up crucial benefits from the point of view of cost‐effectiveness and volume‐compactness improvements of induction motor drives especially in large‐scale industries such as the automotive one where electric and hybrid propulsion systems are currently regarded as an interesting alternative to substitute or to assist the thermal propulsion systems.Originality/valueThe implementation of the RFOC in FSTPI‐fed induction motor drives is feasible and exhibits almost the same performance as those obtained by conventional SSTPI‐fed induction motor drives under the same control strategies.

The double-fed induction generator wind turbine has recently received a great attention. The steady state performance and response of double fed induction generator (DFIG) based wind turbine are now well understood. This paper presents the analysis of stator and rotor flux linkage dq models operation of DFIG under different faults and at different locations.

This paper proposes a parameter identification method of induction motors (IMs) at a standstill using integral calculations. The rotor time constant and magnetizing inductance are identified. During identification process, the induction motor to be tested is consistently excited according to a pre-determined current reference. Using the pre-determined current, the tested motor emulates the rated rotor flux and the rated slip condition even at a standstill. Therefore, the identification result is quite accurate. And, this method is based on integral calculation so that the results are robust to measurement noise. The repeatability of the identification result is remarkable. Due to the simplicity of the proposed technique, this method can be easily applied to the commercial inverter products. Experimental results confirm the effectiveness of the proposed method.

Since the rotor resistance is associated with a slip calculation, the precise identification of rotor resistance has a crucial impact on the dynamic behavior of the whole Indirect Field Orientation Control. This paper presents a new technique based on Model Reference Adaptive System scheme for on-line estimation of an induction motor rotor resistance. The proposed rotor parameter identification is based on the rotor flux of along the d-axis, where the voltage model of induction motor is adapted for a reference model that does not include the rotor resistance parameter, while the current type model in the synchronous reference frame is used to an adjustable model. The validity of rotor resistance estimation is verified by simulation results.

The performance of adaptive full order observer for speed sensorless induction motor drives can be improved further though it has been researched for many years. A novel speed estimation algorithm with estimated rotor flux error and the corresponding feedback gain design method are proposed in this paper. Through Lyapunov's theorem, the stability of proposed speed estimation algorithm is proved. The sensitivity of speed estimation to motor parameter deviation is reduced. Finally the feasibility of proposed two methods is verified by experiments.

A series of laboratory modules will be discussed in this chapter, which have been designed to lead the reader through the development phases needed to understand and work with a sensorless field-oriented IM drive. Sensorless control implementation is based on the use of the InstaSPIN algorithm, which will be configured for different modes of operation. This implies application of the algorithm as a ‘software encoder’ as well as full motor parameter identification. In addition, a special inductance machine algorithm referred to as ‘PowerWarp’ will be discussed, which allows energy efficient operation under partial load conditions.

A series of laboratory modules will be discussed in this chapter, which have been designed to lead the reader through the development phases needed to understand and work with a sensorless field-oriented PM drive. Sensorless control implementation is based on the use of the InstaSPIN algorithm, which will be used in different modes of operation. This implies use of the algorithm as a ‘software encoder’ as well as full motor identification, online resistance estimation and field-weakening. Implementation phases B, C and C+ are discussed in this chapter. For phase B development a so called ‘processor in the loop’ (PIL) approach is introduced in which case the processor is part of the simulation process. This approach is required because the sensorless algorithm resides in hardware only.

A new control strategy is investigated for Doubly Fed Induction Generators (DFIGs). It exercises control over the generator terminal voltage and output power by adjusting the magnitude and angle of the rotor flux vector. It is shown that this control strategy leads to low interaction between the power and voltage control loop, better system damping and voltage recovery following faults, and it also provides enhanced frequency regulation capability compared with that achieved with existing DFIG controllers described in the open literature. The dynamic performance of the proposed DFIG control is tested for small and large disturbances using a generic network that combines wind and conventional synchronous generation. Simulation results are presented and discussed that demonstrate the capabilities of the new strategy to enhance DFIG performance and its contribution to network operation.

This article presents an adaptive rotor flux position observer. Compared with the traditional machine equation based observer, the salient advantage of this method is that it does not need the information of any machine parameter. Thus, potential performance deterioration due to parameter deviation or detuning is avoided. The stability and convergence can be guaranteed when the error transfer function is strictly positive real. The estimated rotor flux position is used to implement the field orientation control. Intensive simulation results are given in this article to validate the proposed method. Good dynamic performances of the driver based on the adaptive observer are also reported.

This paper is an attempt to synthesize the direct torque and rotor flux control (DTRFC) algorithms of induction motor using sliding-mode theory. The choice of the sliding-mode theory has been motivated by the presence of switches in the voltage-source inverter (VSI). Changes in the state of the switches cause the variation in the topology of the controlled system. In addition, this theory offers a mathematical process that allows rigorous procedures of analysis and synthesis. The developed voltage vector is generated by two methods: direct control of the VSI (hysteresis VSI control), and indirect control of the VSI using space-vector modulation. In addition, taking into account the complementarity of the advantages of each VSI control algorithm, the high dynamic performance of the direct control and the smoothness of the indirect control, the idea of the dynamic reconfiguration of DTRFC algorithms is proposed.

This paper deals with a robust H2/H∞ synthesis and an analysis technique applied to an induction motor. In order to robustify a linearizing decoupled feedback against parametric variations, H2/H∞ controllers with a reference model are added. The main interests are performances and real decoupling between the rotor flux and the speed in spite of parameter variations. A stability analysis method using parameter-dependent Lyapunov function is also proposed to verify the global stability. Real time implementations are carried out.