Vector Controlled Induction Motor Research Articles

Concurrent PI Controller Design for Indirect Vector Controlled Induction Motor

AbstractIn this work, a concurrent proportional integral (PI) controller design technique is addressed for indirect vector controlled induction motor (IVCIM). For this, a full‐order induction motor (IM) model is employed that includes the stator current dynamics. The current‐loop proportional integral (PI) controllers are tuned to use the attributes of such dynamics. The robustness against load torque and rotor resistance variations are incorporated in the design problem. This method is implemented using a static output feedback scheme in which iterative linear matrix inequality (ILMI) based H∞ control technique is applied. The simulation and experimental comparison with existing designs show the superiority of proposed method and practical interest for industry use.

An Active Damping Stabilization Scheme for the Suppression of the DC-Link Oscillation in Metro Traction Drive System

The dc-link oscillation is a typical phenomenon happening in the metro traction drive system (MTDS) due to the negative input impedance associated with the constant power load, which is considered as a thorny problem that needs to be resolved well. This paper proposes an active damping stabilization scheme based on inverter power regulation that can effectively eliminate the dc-link oscillation of the MTDS. The proposed stabilization scheme is mainly composed of two parts: 1) the generation of damping power; and 2) the inverter power control loop. The damping power, linked to the deviation of the dc-link voltage through the gain units, is fed back to the vector-controlled induction motor drive system to establish the inverter power control loop. From this control loop, the added q -axis current is obtained, which is regarded as the stabilization term. The additional stabilization term is combined with the q-axis current command of the induction motor for achieving the improvements of the drive performance and the system stability. The effectiveness of the proposed active damping stabilization scheme is verified by simulation and hardware-in-the-loop tests.

Disturbance Rejection Analysis and FPGA-Based Implementation of a Second-Order Sliding Mode Controller Fed Induction Motor Drive

This paper presents a unified approach to deal with sliding mode controllers used for induction motor drives. The study digs deep to identify matched and unmatched disturbances and derive conditions to satisfactorily reject the same. The investigation reveals fundamental limitations of hysteresis (first-order sliding mode) controllers those can be overcome by higher order controllers. Second-order sliding mode controllers are investigated to achieve disturbance rejection and chattering free performance. It is shown that the drive with second-order sliding mode controllers maintains constant switching frequency and decoupling between torque and flux simultaneously on the face of sudden speed, load, or parameter variations. Also, it is shown that the dynamic performance can be improved further at higher sampling frequencies keeping the switching frequency constant. Extensive simulations are carried out in MATLAB/SIMULINK. Implementation of such a drive becomes feasible with low cost field programmable gate arrays (FPGAs) due to their inherent parallel processing capability. A vector-controlled induction motor drive is developed and the controller is implemented using FPGA to corroborate the simulation results through experimentations.

Sliding‐mode observer‐based speed‐sensorless vector control of linear induction motor with a parallel secondary resistance online identification

This study proposes a speed estimation scheme for the sensorless-vector-controlled linear induction motor (LIM) drives for medium-low-speed maglev applications, which is composed of two parts: (i) a sliding mode model reference adaptive system observer for speed estimation; and (ii) a parallel secondary resistance online identification for achieving the improvements of the proposed speed estimation scheme performance. The sliding mode observer (SMO) is established on the basis of the state space-vector model of the LIM considering the dynamic end effect. Based on SMO, both speed and secondary resistance estimation algorithms are obtained by utilising Popov's hyperstability theory. Moreover, the Lyapunov stability theory is adopted for the stability analysis of the proposed speed estimation scheme. The effectiveness of the proposed speed estimation algorithm has been verified and compared with the performance of the conventional speed estimation scheme based on single-manifold SMO by the simulation and hardware-in-the-loop tests.

Single-Stage PV Array Fed Speed Sensorless Vector Control of Induction Motor Drive for Water Pumping

This paper deals with a single-stage solar powered speed sensorless vector controlled induction motor drive for water pumping system, which is superior to conventional motor drive. The speed is estimated through the estimated stator flux. The proposed system includes solar photovoltaic (PV) array, a three-phase voltage source inverter, and a motor-pump assembly. An incremental-conductance-based maximum power point tracking algorithm is used to harness maximum power from a PV array. The smooth starting of the motor is attained by vector control of an induction motor. The desired configuration is designed and simulated in MATLAB/Simulink platform and the design, modeling, and control of the system are validated on an experimental prototype developed in the laboratory.

A Prediction-Based Current Sampling Scheme Using Three Resistors for Induction Motor Drives

In the traditional three-resistor-based current sampling scheme, the sampled currents will become inaccurate when the duration of zero-voltage vectors of an inverter is too short, which leads to a limited modulation index (MI). To overcome this problem, an improved three-resistor sampling method is proposed by establishing a predictive current model of an inverter load, which is that of an induction motor on the synchronous rotating frame for the demonstration purpose in this paper. The principle of this method is detailed in the paper. Then a simulation model of a vector-controlled induction motor drive that utilizes the proposed current sampling scheme is built in the Simulink environment. Finally, the experiment on the new sampling scheme is performed in both steady-state and dynamic conditions. The results verify that the existing current sampling problems can be solved effectively and the motor can perform well with higher MI under the new scheme. As a result, the loading capacity of the system can be enhanced notably.

Speed estimation vector-controlled induction motor drive based on fuzzy logic control flux estimator

A current-and-voltage serial-model stator flux estimator, based on fuzzy logic control for a speed estimation stator flux vector-controlled induction motor drive, is proposed in this study. Stator ...

A combined speed estimation scheme for indirect vector-controlled induction motors

In this paper a novel speed estimation scheme, combining sliding mode observer (SMO), model reference adaptive system (MRAS), and feedforward control, is proposed for indirect vector-controlled induction motors. Firstly, an intermediate current variable is defined to simplify the $$\Gamma $$ -type representation of induction motor. With the definition, a SMO is designed secondly, where the unknown terms in the current equations are replaced with the sliding mode controls. In sliding mode, the dynamics about the equivalent control components are feasible to be derived by solving the sliding mode equations. Following that another set of state equations about the equivalent control components themselves are derived, aiming to form a MRAS with the rotor speed as the adapting parameter. The references of the state variables in the MRAS are provided by filtering out the high-frequency components in the sliding mode functions in the SMO. Meanwhile, a crude value of the rotor speed, calculated directly from the equivalent control components, are fed forward into the speed adaptation mechanism in the MRAS to improve the dynamic performance of the speed estimation. As shown through simulation and experiments, this proposed combined speed observation scheme exhibits better stable and dynamic performance and satisfactory parameter robustness.

Novel Speed and Current Sensor FDI Schemes with an Improved AFTC for Induction Motor Drives

This paper focuses on speed and current sensor Faults Detection and Isolation (FDI) in an Induction Motor (IM) drive. The effect of sensors faults on the IM vector control is presented, then, new detection and isolation approaches are suggested. Speed sensor faults are detected when an error between only two points from speed data exceeds a certain threshold. An algorithm based on RMS currents is developed to detect and isolate any faulty current sensor. This requires three current sensors, each per phase. Besides, open circuit faults of inverter power switches are taken into account too. To ensure continuous functionality of the drive, we conceived an Active Fault Tolerant Controller (AFTC) with smoother reconfiguration feature. Simulations in Matlab/Simulink are carried out to show the efficiency of the suggested schemes.

Research in Sensorless Vector Control of Induction Motor based on MRAS Technique

Research in Sensorless Vector Control of Induction Motor based on MRAS Technique

Application of Sensorless Sliding Mode Observer in Control of Induction Motor Drive

Induction motors are widely used in an industry and it is necessary to improve control methods for induction motors to increase the efficiency of them. In this paper, sliding mode controllers are proposed instead of traditional PI controllers in vector control of induction motor drives. Moreover, rotor speed is estimated by a sliding mode observer. In addition, the robustness of control and observer algorithms are also proved by Lyapunov’s criterion. The experiments are obtained in different speed changes of an induction motor drive. These experimental results confirm the dynamic properties of a sensorless sliding mode control of an induction motor drive.

Robust fuzzy fault tolerant control for induction motor subject to sensor fault

This study presents a strategy of fault tolerant control (FTC) to keep the vector controlled induction motor (IM). The aim is to minimise the effect of the sensor fault and the parametric uncertainties. Firstly, a fuzzy proportional multiple integral observer (PMIO) is used to estimate simultaneously the system state and the sensor fault. Secondly, a feedback robust state tracking control is synthesised to guarantee the control performances. The proposed controller is based on a T-S reference model to specify the desired trajectory. The performances of the trajectory tracking are analysed using the Lyapunov theory and the L2 optimisation. The gains of the observer and controller are obtained by solving a set of LMIs constraint. Finally, simulation results are given to show the effectiveness of the proposed control scheme.

Robust fuzzy fault tolerant control for induction motor subject to sensor fault

This study presents a strategy of fault tolerant control (FTC) to keep the vector controlled induction motor (IM). The aim is to minimise the effect of the sensor fault and the parametric uncertainties. Firstly, a fuzzy proportional multiple integral observer (PMIO) is used to estimate simultaneously the system state and the sensor fault. Secondly, a feedback robust state tracking control is synthesised to guarantee the control performances. The proposed controller is based on a T-S reference model to specify the desired trajectory. The performances of the trajectory tracking are analysed using the Lyapunov theory and the L2 optimisation. The gains of the observer and controller are obtained by solving a set of LMIs constraint. Finally, simulation results are given to show the effectiveness of the proposed control scheme.

Research on Induction Motor Vector Control System Based on Internal Model Decoupling

As a high-performance variable frequency control technology, vector control has been widely used in the field of AC speed regulation. However, the cross-coupling potential of the induction motor after the vector transformation still affects the system performance. Therefore, the method is studied in which stator current is decoupled to excitation component and torque component using internal model control, and the internal model decoupling stator current controller is designed based on rotor field orientation. The simulation model of induction motor vector control system based on internal model decoupling is constructed with Matlab/Simulink. The simulation result shows that the internal model controller is superior to the traditional PI controller in disturbance-rejection performance and robustness.

A Numerical Bifurcation Analysis of Indirect Vector-Controlled Induction Motor

Indirect vector-controlled induction motor (IVCIM) dynamics is well known for having different bifurcation behavior, viz., saddle-node bifurcation, Hopf bifurcation (HB), Bogdanov–Takens bifurcation, and zero-HB. A numerical analysis of these bifurcations for proportional–integral-controlled IVCIM is made in this brief using full-order IM model. Some new observations on the bifurcation behavior are made. Simulation and experimental results are presented validating the bifurcation behaviors.

Neural Adaptive Kalman Filter for Sensorless Vector Control of Induction Motor

This paper presents a novel neural adaptive Kalman filter for speed sensorless field oriented vector control of induction motor. The adaptive observer proposed here is based on MRAS (model reference adaptive system) technique, where the linear Kalman filter calculate the stationary components of stator current and the rotor flux and the rotor speed is calculated with an adaptive mechanism. Moreover, to improve the performance of the PI classical controller under different conditions, a novel adaptation scheme based on ADALINE (ADAptive LInear NEuron) neural network is used. It offers a solution to the PI parameters to stabilize automatically about their optimum values and speed estimation to converge quicker to the real. The proposed adaptive Kalman filter represents a good comprise between estimation accuracy and computationally intensive. The simulation results showed the robustness, efficiency, and superiority of the proposed scheme compared to the classical method even in low speed region.

Performance-Based Linearization Approach for Modeling Induction Motor Drive Loads in Dynamic Simulation

This paper describes a technique to model a vector-controlled induction motor drive in large-scale phasor-level dynamic simulation programs. The performance-based load model is implemented by obtaining the linearized power-voltage and power-frequency transfer functions from test data or from detailed electro-magnetic transient simulation used as a surrogate for test data. Voltage and frequency modulations are performed to obtain the amplitude and phase responses of the detailed vector-controlled drive model for a range of discrete frequencies. The prediction error minimization technique is utilized to generate best-fit analytical transfer function expressions. The electrical interface of the performance-based drive load model is developed to interact with the external system in positive-sequence dynamic simulation programs. The drive model is used to investigate the relative damping effects of drive-connected and direct-connected motors on system voltage and frequency oscillations.

A novel fuzzy logic controller for vector controlled induction motor drive

In this paper, a novel fuzzy logic controller is proposed for vector controlled three phase induction motor. Modelling of the three phase induction motor is done with the help of governing modelling equations. Initially PID controller is interfaced with the induction motor model. Performance of the induction motor with PID controller is analysed under disturbance environment. Speed controller action of this PID controller is found to be poor under disturbance environment. Besides, fuzzy logic based speed controller is interfaced with the three phase induction motor. Performance of the induction motor with fuzzy logic controller under disturbance environment is examined. This fuzzy logic controller overcomes the drawbacks of the conventional PID controller. Tracking performance of this fuzzy logic controller is scrutinized in the disturbance environment. Superior speed controller action is achieved by the proposed fuzzy logic based speed controller for the three phase induction motor.

A novel neural network intelligent controller for vector controlled induction motor drive

In this paper, a novel neural network intelligent controller is proposed for the vector controlled induction motor. Fuzzy logic controller is interfaced with the three phase induction motor initially. Effectiveness of this fuzzy logic controller with the three phase induction motor is analysed under disturbance environment. It is identified that fuzzy logic controller is not up to the mark in terms of speed tracking. Therefore, neural network based intelligent controller is interfaced with the three phase induction motor. Performance of this proposed neural network controller is analysed in the disturbance environment. At the end, comparison chart is made to know the effectiveness of the proposed neural network controller with the fuzzy logic controller. This comparison chart is delineated for the various control system parameter aspects. It is recognised that the proposed neural network controller works well in the presence of the disturbances. Moreover, this neural network controller operates adroitly for all the necessary working conditions.

A novel neuro-fuzzy controller for vector controlled induction motor drive

In this paper, a novel neuro-fuzzy controller is proposed for the vector controlled induction motor. Neural network controller is interfaced with the three phase induction motor initially. Performance of this neural network controller with the three phase induction motor is analysed under disturbance environment. It is identified that neural network controller is not working well in terms of speed tracking. Hence neuro- fuzzy controller is interfaced with the three phase induction motor. Performance of this proposed neuro -fuzzy controller is analysed in the disturbance environment. At the end, Comparison chart is made to know the effectiveness of the proposed neuro-fuzzy controller with the neural network controller. This comparison chart is described for the various control system parameter aspects. It is recognised that the proposed neuro-fuzzy controller works well in the presence of the disturbances. Moreover, this neuro-fuzzy controller operates skilfully for all the necessary working conditions.