Vector Controlled Induction Machine Research Articles

An Implementation of Fuzzy to Minimize Electrical Losses in Induction Machine Vector Control

An induction motor is a motor that is difficult to control so it requires synchronous speed due to dynamic load changes which are controlled by the torque current while the field current is kept constant. Thus, in this paper, we implement an adaptive PID controller method with an induction motor using MATLAB which coordinates the speed of two decoupled loads with a three-phase induction motor, where an adaptive Self Tuning Regulator (STR) PID controller is designed and realized to regulate the speed of a three-phase induction motor. using MATLAB software and AVR Atmega16 microcontroller as input and output from the plant with communication using serial RS232. The results show that after coordinating the system with each motor which is given a neural controller and FOC, the motor speed results are obtained which gradually provide synchronous speed so it can be concluded that this system can work well to slow down the plant response. Keywords: Induction Motor, Motor Speed, neural method, PID controller

Parameter sensitivity on the performance of sensor-based rotor flux oriented vector controlled induction machine drive

Parameter sensitivity on the performance of sensor-based rotor flux oriented vector controlled induction machine drive

Control and operation of the MMC‐based drive with reduced capacitor voltage fluctuations

The modular multilevel converter (MMC) has emerged as a suitable topology for high power drive applications. However, the voltage fluctuations of its floating capacitors increase the control complexity of the converter. In this study, the MMC dc-port voltage is manipulated to regulate the amplitude of these fluctuations to a constant value during the whole frequency range. The proposed approach has several advantages when compared with the conventional ones since it minimises the voltage fluctuation in the capacitor cells. Additionally, it decreases the common-mode voltage at low frequencies and the capacitor rms current, increasing their expected lifespan and reducing the winding insulation damages and the leakage currents in the bearing of the machine. The effectiveness of the proposed control strategy is validated with a laboratory-based prototype composed of 18 power cells, feeding a vector-controlled induction machine.

An Integrated Converter and Machine Control System for MMC-Based High-Power Drives

The modular multilevel converter (MMC) is a promising topology for high-power drive applications. However, large voltage fluctuations can be produced in the floating capacitors when the machine operates with high stator currents at low rotational speed. To compensate these oscillations, relatively large mitigation currents are required to keep the capacitor voltages within an acceptable range. In this paper, a new integrated control scheme is discussed to regulate the voltage fluctuations. The strategy is based on closed-loop vector-control of the voltage fluctuations, maintaining them inside a predefined threshold. The proposed control system is also augmented using flux-weakening operation of the machine at low rotational speeds. An experimental prototype composed of 18 power cells, feeding a vector-controlled induction machine in the whole speed range, is used to validate the effectiveness and feasibility of the proposed control strategies.

Application of model-based design tool X2C in induction machine vector control

Open source software tools for model-based design of embedded control systems represent a new method for rapid development and testing of advanced control structures in modern electric drives. The new concept of one of those tools, X2C, is presented in this paper, and in order to evaluate its performance in the development of complex control systems, it is applied to implement induction machine vector control. Based on the simulation model of the drive developed in PLECS, the parameters of the controllers were determined. The algorithm for the vector control of the induction machine was developed in X2C, implemented on the digital signal processor and applied to the real system. The system was tested during the no-load acceleration, deceleration, and reversing of the motor, while measuring the electrical and mechanical variables. Finally, the quantitative comparison of the experimental results and the results obtained by the equivalent simulations, based on the Integral Squared Error criterion, revealed that these results were well matched. This finding suggested that the control system was successfully implemented, thereby confirming the effectiveness of X2C tool in this particular type of application. With this work it has been shown that a transition from simulation to actual environment is rapidly achieved, with a simple verification of implemented methods accompanying the process. Realization of this work is a step forward in the utilization of open source software packages for implementation of induction machine vector control with the purpose of rapid verification of simulation models.

A Novelty Design Of Minimization Of Electrical Losses In A Vector Controlled Induction Machine Drive

The induction motor has in the industry . More attention has been a focus to develop and design of induction motor drive. With the method of vector control novelty prove the efficiency of induction motor over their entire speed range. In this paper desirable to design a loss minimization controller which can improve the efficiency. Also, this research described Modeling of an induction motor with core loss included. Realization of methods vector control for an induction motor drive with loss element included. The case of the loss minimization condition. The procedure was successful to calculate the gains of a PI controller. Though the problem of obtaining a robust and sensorless induction motor drive is by no means completely solved, the results obtained as part of this work point in a promising direction.

Single-current-sensor-based active front-end-converter-fed four quadrants induction motor drive

Induction motor (IM) is a workhorse of the industry, whose dynamics can be modified close to that of a separately excited DC machine by field-oriented control technique, which is commonly known as vector control of induction machine. This paper presents a complete performance of the field-oriented control of IM drive in all four quadrants with a single-current-sensor-based active front end converter whose work is to regulate DC link voltage, draw pure sinusoidal currents at unity power factor and to facilitate bi-directional power flow between the grid and the drive. The entire system is completely modelled in MATLAB/SIMULINK and the results are discussed in detail. The vector control analogy of the back to back converters is highlighted along with the experimental results of field-oriented control of induction machine using a dsPIC30F6010A digital signal controller.

Vector Control of Induction Machine with Estimates and Adaptation of Rotor Time Constant

The variation of the rotor time constant exerts a dominant effect in the performance degradation of the orientation of the rotor flux method of induction machine and the online estimation of the time constant (Tr) is necessary in order to use it in the flux orientation and keeping the performance of the vector control. We presented our work vector control of induction machine by estimating and online adaptation of the rotor time constant of our machine only by measurement of voltage, current and speed, in line on the machine, to provide information to the orientation block on the variation of the parameter studied Tr.

TS Fuzzy Logic-Based Rotor Resistance Tuning in case of Induction Machine Vector Control

In this paper, we focus on the estimation of the rotor resistance to online tune the controllers in case of the Indirect Rotor Field Orientation Control (IRFOC) of Induction Machine (IM). The proposed method is based on the development of an adaptive Takagi-Sugeno (TS) fuzzy flux observer, described in a d-q synchronous rotating frame, to concurrently estimate the IM states and the rotor resistance variation. An investigation of the local pole placement is carried out in order to guarantee both the stability and specified observer dynamic performances. The observer's gains design is based on the resolution of sufficient conditions driven into LMIs terms (Linear Matrix Inequalities). Simulation and experimentation are carried out to show the effectiveness of the proposed results.

A Lyapunov Function for Vector Control Drives in Induction Machines

In this paper a useful Lyapunov function for vector control of induction machines is introduced. To do this, some beneficial theorems are reviewed and by applying these theorems and state equations to a vector control drive, its candidate Lyapunov function is achieved. Range of set points such as reference speed, reference flux linkage values and speed controller gain is obtained for such a drive and therefore these values can be set offline to avoid unstable behavior. The simulated and experimental results are given in the last section of the paper to show the efficacy of the given Lyapunov function.

Fuzzy speed estimation in the case of sensorless induction machine vector control

This paper deals with the problem of sensorless indirect field oriented control of an induction machine. Based on the fourth-order nonlinear model, we propose a novel structure of a full-order Takagi-Sugeno (TS) adaptive observer, through which we ensure the estimation of IM states and the rotor speed, which is considered as an immeasurable premise variable. This approach satisfies global stability for all operating conditions and operates under unknown applied load torque. In this work, a TS fuzzy model is presented to approximate a nonlinear IM model in the stationary rotating reference frame. A TS adaptive observer is then described. We then design observer gains to guarantee specified observer dynamic performances through a D-stability analysis. Meanwhile, a TS-based scheme is proposed for speed estimation. The synthesis is based on sufficient conditions that are developed and formulated into linear matrix inequalities terms. Simulation and experimental results are given to show the effectiveness of the proposed method.

Thermal Protection of Vector-Controlled IM Drive Based on DC Current Injection

A technique for stator-resistance-based thermal protection suitable for a low-cost vector-controlled induction machine (IM) drive is suggested in this paper. In order to provide accurate stator resistance monitoring at medium and high speeds, the dc signal injection-based method is selected. The main property of the scheme is that small regulated dc current is periodically injected in the stator windings without interrupting the flux and torque control loops. In the proposed scheme, inverter nonlinearities are properly compensated and accurate resistance estimation is achieved with minimal level of injected dc current. This results in consistent and controllable torque ripple, which is minimal and constant for any actual stator resistance value. Estimated stator resistance can be also used for control algorithm tuning. The method is implemented in a fixed-point microprocessor and tested on a low-cost shaft-sensorless IM drive under various operation modes.

TS Fuzzy Logic-Based Rotor Resistance Tuning in case of Induction Machine Vector Control

In this paper, we focus on the estimation of the rotor resistance to online tune the controllers in case of the Indirect Rotor Field Orientation Control (IRFOC) of Induction Machine (IM). The proposed method is based on the development of an adaptive Takagi-Sugeno (TS) fuzzy flux observer, described in a d-q synchronous rotating frame, to concurrently estimate the IM states and the rotor resistance variation. An investigation of the local pole placement is carried out in order to guarantee both the stability and specified observer dynamic performances. The observer's gains design is based on the resolution of sufficient conditions driven into LMIs terms (Linear Matrix Inequalities). Simulation and experimentation are carried out to show the effectiveness of the proposed results.

Fuzzy Sliding Mode Speed Controller for a Vector Controlled Induction Motor

This paper presents a speed fuzzy sliding mode controller for a vector controlled induction machine (IM) fed by a voltage source inverter (PWM). The sliding mode based fuzzy control method is developed to achieve fast response, a best disturbance rejection and to maintain a good decoupling. The problem with sliding mode control is that there is high frequency switching around the sliding mode surface. The FSMC is the combination of the robustness of Sliding Mode Control (SMC) and the smoothness of Fuzzy Logic (FL). To reduce the torque fluctuations (chattering), the sign function used in the conventional SMC is substituted with a fuzzy logic algorithm. The proposed algorithm was simulated by Matlab/Simulink software and simulation results show that the performance of the control scheme is robust and the chattering problem is solved.

Extension of the Operating Speed for Vector-Controlled Induction Machine Drives in the Overmodulation Range

This paper proposes a novel current control scheme for vector-controlled induction machine (IM) drives in the overmodulation (OVM) range, with which the voltage utilization of the voltage-source inverter (VSI) can be maximized. In the OVM region, the original voltage reference is modified by changing its magnitude and angle, which causes the motor current to be distorted, resulting in a deterioration of the current control performance. To meet with this situation, the harmonic components in the feedback currents should be eliminated before being input to the PI current controllers. For this, a composite observer is applied to extract the fundamental and harmonic components from the distorted currents, which gives a good performance without a delay and the effect of a fundamental frequency variation. In addition, through a detailed analysis of the response of the PI current controllers in the OVM range, the effectiveness of using the composite observer is demonstrated. Simulation and experimental results for a 3-kW induction motor drive are shown to verify the validity of the proposed method.

A Study of Vector Control of Induction Machine Considering Iron Loss

Because of the imperfects of traditional induction control system neglecting iron loss, this paper introduced the parallel equivalent resistance of iron loss, and use new mathematical model of induction machine to establish a more accurate vector control system. However, the increased coupling of parameters in induction machine caused by iron loss is undeserved. We simplified the decoupled system and utilize fuzzy adaptive mechanism to make the speed tuning process more intelligent and robust. The load and non-load experiments show that fuzzy PID controller overcomes the shortcomings of the traditional, reduces the detrimental impacts of iron loss, take advantages of the active impacts from it as well. In the new control system, it adapts to both inner and environmental parameters well, the torque and exciting current are smoother and lower. So, it is extremely meaningful and conducive to the realization of the economical speed tuning.

Modified Euler integration based control of a five-phase induction motor drive

In principle, control methods for multi-phase machines are the same as for three-phase machines. Variable speed induction motor drives without mechanical speed sensors at the motor shaft have the attractions of low cost and high reliability. To replace the speed sensor, information of the rotor speed is extracted from measured stator currents and voltages at motor terminals. Vector-controlled drives require estimating the magnitude and spatial orientation of the fundamental magnetic flux in the stator or in the rotor. Open-loop estimators or closed-loop observers are used for this purpose. They differ with respect to accuracy, robustness, and sensitivity against model parameter variations. This paper analyses operation of a modified Euler integrationbased sensorless control of vector controlled five-phase induction machine with current control in the stationary reference frame. A linear neural network has been then designed and trained online by means of back propagation network (BPN) algorithm, differently from that in the literature which employs a nonlinear back propagation network (BPN) algorithm. The Artificial Neural Network (ANN)-Model Reference Adaptive System (MRAS) based sensorless operation of a three-phase induction machine is well established and the same principle is extended in this paper for a five-phase induction machine. Performance, obtainable with hysteresis current control, is illustrated for a number of operating conditions on the basis of simulation results. Full decoupling of rotor flux control and torque control is realised. Dynamics, achievable with a five-phase vector controlled induction machine, are shown to be essentially identical to those obtainable with a three-phase induction machine. International Journal of Engineering, Science and Technology, Vol. 2, No. 6, 2010, pp. 218-230

Simulation of Induction Machine Drive by Composite Model Flux Observer

 Abstract—This paper presents a robust simulation of direct vector control of induction machine (IM) drive on the rotor flux direction with composite model flux observer. In the indirect vector control of IM, current reference values are used for estimation angle of the rotor flux space vector (ARFSV), however using current reference values instead of current real values can decrease accuracy of ARFSV. In the direct vector control, current real values (current feedback) estimate the ARFSV. ARFSV estimation can be performed by current model flux observer and voltage model flux observer. These observers have their own limitations. The composite model reduces disadvantages of every individual ones. Simulation of composite model is applied to induction machines and obtained results compare to the classical current and voltage models. The composite model approach shows great advantages over those classic ones, a.e. speed control over wide range of motor operation and enough short settling time. All these remarkable advantages support application of composite model in ARFSV.

Learning improvement by using Matlab simulator in advanced electrical machinery laboratory

This paper deals with using simulators such as MATLAB/SIMULINK to work on complicated problems in electrical machines. Simulation of direct vector control of induction machine (IM) drive on the rotor flux direction with composite model flux observer can improve electrical machine learning's of graduate and under graduated students, hi the indirect vector control of IM, current reference values are used for the estimation angle of the rotor flux space vector (ARFSV), however using current reference values instead of current real values can decrease accuracy of ARFSV. hi the direct vector control, current real values (current feedback) estimate ARFSV. The ARFSV estimation can be performed by the current model flux observer and voltage model flux observer. These observers have some restrictions. But The composite model reduces disadvantages of every individual ones. In fact, Simulation of the composite model is applied to induction machines to get results compare to the classical current and voltage models. The interesting point is that the composite model approach shows great advantages over those classic ones, i.e. speed control over the wide range of motor operation with enough short settling time. All these remarkable benefits support the application of composite model in ARFSV. © 2010 Published by Elsevier Ltd.

Flux level selection in vector-controlled dual stator winding induction machines

The dual stator winding induction machine has two three-phase stator windings with dissimilar number of poles. This machine can be regarded from the point of view of control as two different induction machines coupled by a rotor. To improve the machine's performance, the total flux generation must be correctly distributed between the two windings. This study focuses on the flux distribution necessary to achieve a nearly maximum torque per stator ampere operation, which is indicated in applications requiring high dynamics. In addition, efficiency and voltage utilisation will be also considered.