Field Oriented Control Of Induction Motor Research Articles

Robustness Enhancement of Fractionalized Order Proportional Integral Controller for Speed Control of Indirect Field-Oriented Control Induction Motor

Robustness Enhancement of Fractionalized Order Proportional Integral Controller for Speed Control of Indirect Field-Oriented Control Induction Motor

Direct Field-Oriented Control of Induction Motor with Discrete Full-Order Flux Observer

Direct Field-Oriented Control of Induction Motor with Discrete Full-Order Flux Observer

Model Predictive Current Control of an Induction Motor Considering Iron Core Losses and Saturation

The paper considers the model predictive current control (MPCC) of an induction motor (IM) drive and evaluates five IM models of different complexities—from conventional to magnetic saturation, iron losses, and stray-load losses—for the MPCC design. The validity of each considered IM model and the corresponding MPCC algorithm is evaluated by comparison of the following performance metrics: the total harmonic distortion of the stator current, the average switching frequency, the rotor flux magnitude error, the rotor flux angle error, and the product of the first two metrics. The metrics’ values are determined in wide ranges of the rotor speed (0.1–1 p.u.) and load torque (0–1 p.u.) through simulations performed in the MATLAB Simulink environment. The obtained results allow us to identify the IM model that offers the best tradeoff between the practicability and accuracy. Furthermore, a control effort penalization (CEP) is suggested to reduce the average switching frequency and, hence, the power converter losses. This involves constraining the simultaneous switching to a maximum of two branches of the three-phase power converter, as well as inclusion of the weighted switching penalization term in the cost function. Finally, the performance—both steady-state and dynamic—of the proposed MPCC system with CEP is compared with that of the analogous field-oriented controlled (FOC) IM drive. The inverter switching frequency is reduced more than twice by including the frequency-dependent iron-loss resistance in the MPCC. It is additionally reduced by implementing the proposed CEP strategy without sacrificing many other performance metrics, thus achieving a performance comparable to the FOC IM drive.

Chattering Reduction on Low-Speed Indirect Field Oriented Control Induction Motor Using Second Order Sliding Mode Control

Chattering Reduction on Low-Speed Indirect Field Oriented Control Induction Motor Using Second Order Sliding Mode Control

Digital Twin Model of Electric Drives Empowered by EKF.

Digital twins, a product of new-generation information technology development, allows the physical world to be transformed into a virtual digital space and provide technical support for creating a Metaverse. A key factor in the success of Industry 4.0, the fourth industrial revolution, is the integration of cyber-physical systems into machinery to enable connectivity. The digital twin is a promising solution for addressing the challenges of digitally implementing models and smart manufacturing, as it has been successfully applied for many different infrastructures. Using a digital twin for future electric drive applications can help analyze the interaction and effects between the fast-switching inverter and the electric machine, as well as the system's overall behavior. In this respect, this paper proposes using an Extended Kalman Filter (EKF) digital twin model to accurately estimate the states of a speed sensorless rotor field-oriented controlled induction motor (IM) drive. The accuracy of the state estimation using the EKF depends heavily on the input voltages, which are typically supplied by the inverter. In contrast to previous research that used a low-precision ideal inverter model, this study employs a high-performance EKF observer based on a practical model of the inverter that takes into account the dead-time effects and voltage drops of switching devices. To demonstrate the effectiveness of the EKF digital twinning on the IM drive system, simulations were run using the MATLAB/Simulink software (R2022a), and results are compared with a set of actual data coming from a 4 kW three-phase IM as a physical entity.

A new simplified sensorless direct stator field-oriented control of induction motor drives

A field-orientation scheme is a typical control technique of induction motors to obtain sophisticated performance. The stator field-oriented control is less sensitive to parameter variations than the rotor field-oriented control. In addition, the estimation of the stator flux is more accurate than that of the rotor flux. Therefore, the stator flux system is considered a good choice for variable speed drives. However, the traditional configuration of the system includes four PI controllers which need effort in tuning. In this article, simple calculations are proposed such that the configuration and performance of the stator field-oriented control systems are improved by including only two PI controllers. In addition, with the aid of the machine phase axes, a simple procedure for the speed estimation target is suggested to effectively estimate the rotor speed of the machine with a direct estimation without any need for a PI controller or additional observers in the speed observer procedure. The obtained results confirm the effectiveness of the proposed control scheme.

Correction of Field Orientation Inaccuracy Caused by Resolver Periodic Error and Rotor Time Constant Variation for Indirect Field-Oriented Control Induction Motor Drives

This article proposes an algorithm correcting the field orientation inaccuracy caused by resolver periodic error and rotor time constant variation. It is found that the periodic error brings harmonic current vectors and torque ripples while the rotor time constant variation makes <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dq</i> currents deviate from the reference values. The cross-product of fundamental and harmonic current vectors contains the information of resolver periodic error. The gradient descent method with a variable step is introduced to compensate the periodic error. During the process, the cross-product is minimized. A new form of cross-product calculation is derived to reduce the computation time. The rotor time constant is identified by the reactive-power based model reference adaptive system (MRAS). Voltages and currents in the stationary reference frame are used in the reference model to avoid the influence of resolver periodic error. Appropriate parameters of the MRAS are selected to guarantee the stability. The algorithm is integrated with an induction motor drive which is based on indirect field-oriented control. The feasibility of the proposed algorithm is verified by simulation results and experiments.

An 18-Pulse Converter and 4-Level Cascaded Inverter Based Induction Motor Drive

This article presents a topology of an 18-pulse ac–dc and 4-level cascaded converters for a medium-voltage drive application. An isolated transformer-based 18-pulse ac–dc converter is used for enhancing the power quality at the supply end in a medium-voltage induction motor drive. Apart from this, an inverter topology, which is designed by the cascading of a two-level voltage source inverter, is designed for medium-voltage drive applications. This topology requires a smaller number of components in comparison to the hybrid four-level inverter topology, which is presented in the literature. The design of the system is carried out for an 18-pulse ac–dc converter and 4-level inverter feeding an indirect field-oriented control induction motor drive. The effect of switching and conduction losses performance of the presented inverter is analyzed and compared with the profile of the four-level inverter topology presented in the literature. A laboratory prototype of the presented 18-pulse converter and 4-level inverter is also developed to capture the performance in different operating states with a 7.5-kW (10 hp) (reduced scale) induction motor drive. The obtained results justify the practicality of this design and validate the simulated results, which are analyzed on a 298.4-kW induction motor drive. The performances of the drive system are studied based on the industry applications requirements point of view, such as power quality, losses, and dynamic stability.

Postfault Direct Field-Oriented Control of Induction Motor Drive Using Adaptive Virtual Current Sensor

Electric drives immune to failures of selected elements of the power system or measuring sensors have been the subject of research in recent years, due to the growing interest in systems with an increased level of safety. This article concerns the analysis of the direct field-oriented control induction motor drive after the failure of all stator current sensors. An adaptive virtual current sensor (AVCS) was used to estimate the stator current, based on the measurement of the motor angular velocity and the voltage in the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\text{DC}\ (u_{\text{DC}})$</tex-math></inline-formula> of the voltage-source inverter. This article presents the possibility of improving the accuracy of stator current estimation using the original approximation of changes in rotor resistance depending on the drive operating point when the measurement information about the stator current has been lost. This approximation was determined experimentally during the normal operation of the drive using a rotor resistance estimator. The determined approximate lookup functions were used to adapt the rotor resistance in the AVCS during the drive system operation in a postfault mode. This approach has made it possible to significantly improve the accuracy of the stator current reconstruction, especially under low speeds and load torques, which was demonstrated in experimental studies <bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">.</b>

Space vector PWM ‐based current error boundary investigations for three‐level VSI fed induction motor drive

Field oriented control (FOC) of induction motor (IM) powered by a three-level voltage source inverter (3L -VSI) with space vector (SV) based continuous and dis -continuous pulse width modulation (PWM) is presented in this paper. The current error variations in each sector with above-mentioned PWM techniques are monitored and analyzed mathematically. These boundary investigations play a great role in the implementation of Current Error Space Phasor (CESP) based hysteresis current controller (HCC) which incorporates the advantages of a constant switching frequency PWM fed three-level inverter (3LI) into highly dynamic current controlled – voltage source inverter. As a preliminary step, FOC of IM with the conventional space vector PWM and bus clamping PWM (BC30 and BC60) fed 3LI have been simulated using SIMULINK toolbox of MATLAB. Transient analysis of the drive with acceleration, deceleration, and load change studies with different switching schemes are analyzed with d SPACE RTI1103 experimentation on a 2.2 kW three-phase IM drive in detail.

Energy-efficient field-oriented control for induction motors taking core losses into account

Energy-efficient field-oriented control for induction motors taking core losses into account

Self-Tuning Observer for Sensor Fault-Tolerant Control of Induction Motor Drive

This paper introduces a new solution for the speed and current sensor fault-tolerant direct field-oriented control of induction motor drives. Two self-adjusting observers derived from a modified current-based model reference adaptive system (CB-MRAS) are presented. Finally, the recursive least squares method was used to estimate the parameters of the used observers. The method, in the proposed solution, provides a very fast and accurate finding of the observer parameters while maintaining relative simplicity and ease of implementation. The presented algorithm eliminates the CB-MRAS observer dependence on the induction motor parameters and also compensates for the inaccuracies in the evaluation of the stator voltage vector. The proposed fault-tolerant control offers the drive operation while either a speed sensor or one/two current sensors fault occurs. The drive still works with the direct field-oriented control even when no current sensors are healthy. The proposed scheme was simulated in the MATLAB/Simulink software environment. Then the algorithm was implemented in a floating-point digital signal controller (DSC) TMS320F28335 and tested on an induction motor drive prototype of rated power of 2.2 kW to validate the proposed schemes.

Bifurcation and Chaos in indirect field-oriented controlled induction motor drive system

In this paper, the higher-order three-phase indirect field-oriented controlled (IFOC) induction motor is modeled in synchronous reference frame. The IFOC induction motor is analyzed numerically to investigate the system behavior due to control parameters change. The slip speed compensator, integral, and proportional gains variations of the speed loop controller are used to confirm the system dynamics. The simulation results show that the chaos behavior is noted in small region of the slip speed compensator gain which is difficult to be observed through the dominant limit cycles and fixed-point solutions. The effects of the integral and proportional gains change on the system dynamic are verified. Also, the system exhibits period-doubling bifurcation (period-2, period-4, period-8, and period-16) route to chaos. The bifurcation diagram and Lyapunov exponent spectrum assign these situations. The phase portrait and time response results are also presented. The system has multistability and coexistence of different attractors for the same system parameters as represented in the basins of attractions plots.

Maximum Torque Per Watt (MTPW) field-oriented control of induction motor

A new field-oriented control strategy for induction motor is proposed in the paper. It is called Maximum Torque Per Watt (MTPW) and allows obtaining the minimum value of the sum of the stator and rotor losses due to joule effect, and of the iron losses, for a given value of the reference torque and of the motor speed. Iron losses have been modeled according to Steinmetz equation, separating hysteresis and eddy currents and taking into account the dependence both on the frequency and on the peak value of the flux density. Numerical and experimental results are presented to confirm the validity of the proposed approach, which allows achieving significant improvements in the efficiency of induction motor drive.

Simple and Flexible Power Loss Minimizer With Low-Cost MCU Implementation for High-Efficiency Three-Phase Induction Motor Drives

This article presents a simple, practical, and low-cost implementation of a power losses minimization algorithm for three-phase induction motors taking also into account both iron core losses and magnetic saturation. The algorithm evaluates, in real time, the optimal direct axis magnetizing flux component for efficiency enhancement of the drive. A further advantage of the proposed technique is represented by a flexible and low-cost implementation by means of an ATMEL ATSAM3X8E microcontroller. The power loss minimization algorithm is tested preliminarily by means of several simulations, then, experimentally validated by applying the proposed control strategy on a 5.5-kW field-oriented control induction motor drive. Significant results in terms of efficiency enhancement are presented and discussed, demonstrating that the proposed online control can significantly decrease the power losses of the drive.

Current and Speed Sensor Fault Diagnosis Method Applied to Induction Motor Drive

The paper proposes a novel approach based on a current space vector derived from measured stator currents to diagnose speed and current sensor failures in the field-oriented control of induction motor drives. A comparison algorithm between the reference and measured rotor speed is used to detect the speed sensor faults. A counter is added to eliminate the influence of the encoder noise in the diagnosis method. In this approach, estimated quantities are not used in the proposed speed sensor fault diagnosis strategy, which increases the independence between the diagnosis stages in the fault-tolerant control (FTC) method. Moreover, in order to discriminate between the speed sensor faults and the current sensor faults, a new approach combining the current space vector and a delay function is proposed to reliably determine the current sensor failures. The MATLAB-Simulink software was used to verify the idea of the proposed method. Practical experiments with an induction motor drive controlled by DSP TMS320F28335 were performed to demonstrate the feasibility of this method in practice. The simulation and experimental results prove the effectiveness of the proposed diagnosis method for induction motor drives.

Power quality monitoring for a solar PV grid controlled system at non-linear induction drives load

This paper unveils the impact of non-linear induction motor drives on operation of transformer-less single-stage solar photovoltaic (SPV) grid tied inverter system. The system is controlled by an indirect type data-based maximum power point tracking (MPPT) technique. A fuzzy-logic controlled (FLC) dynamic voltage restorer (DVR) is operated coordinating two non-linear induction motor drives load: direct torque flux control (DTFC) and field-oriented control (FOC). Importantly, power quality (PQ) analysis for FOC induction motor drive is validated with DTFC induction motor drive. Results reveal mitigation of unbalanced voltage sag and voltage swell among the SPV converter, load and grid during transient conditions produced by fault. The effectiveness of FLC-DVR at FOC drive load is demonstrated over DTFC drive load and linear load for validation. It is worth mentioning that controlling action of FLC-DVR is implemented effectively at non-linear loads. As illustrated by IEEE-519/1547 standard, a reduction in total harmonic distortion (THD) and DC offset current is reported in grid voltage and current for accuracy. The proposed framework illustrates a comparative PQ study to justify satisfactory performance under varying environmental conditions.

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.

A Novel Speed and Current Sensor Fault-Tolerant Control Based on Estimated Stator Currents in Induction Motor Drives

The paper introduces a novel Fault Tolerant Control (FTC) algorithm based on estimated stator currents to diagnose some faulty states of stator current and speed sensors of Induction Motor (IM) drives. The FTC unit is integrated in the field-oriented control of induction motors to ensure that the IM drive can operate stably when current and speed sensor failures occur. The presented scheme combines two stator current estimators and a rotor speed estimator where a correction coefficient determined from the healthy current sensor is used to enhance the accuracy of the stator current estimation. To verify the capability of the proposed approach, the simulation in MATLAB-Simulink has been accomplished for various conditions of the IM drive, i.e. normal speed, low speed, and very low speed operating ranges. The results have confirmed very good features of the proposed FTC against the current and speed sensor fault in the different speed ranges.

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.