M. A. Fnaiech

Fuzzy Logic and Sliding-Mode Controls Applied to Six-Phase Induction Machine With Open Phases

The faulted mode of a six-phase induction machine (6PIM) denotes that the motor is working with one or more missing phases. This situation leads to torque oscillations and poor tracking behavior. Therefore, the design of a suitable robust control is a challenging task. In this way, this paper presents the application of fuzzy logic and sliding mode controls in order to obtain a high-accuracy positioning of a 6PIM rotor in both healthy and faulted modes. The two control strategies are completely different from a theoretical point of view, but the final objectives are to remove the drawbacks of the specific fault on interest. The experimental results are obtained on a dedicated setup based on a 6PIM coupled with a variable mechanical load and for which up to three phases can be removed.

Sliding Mode Control for Dual Three-phase Induction Motor Drives

This paper deals with the application of the sliding mode control to the dual three-phase induction motor. The sliding mode control (SMC) is a robust non linear control algorithm which uses discontinuous control to force the system state trajectories to join some specified sliding surface. It has been widely used for its robustness to model parameter uncertainties and external disturbances. The simulation results using MATLB/ Simulink are given showing the suitable robustness regarding high level input and output perturbation

A Measurement-Based Approach for Speed Control of Induction Machines

This paper presents an approach to design a measurement-based controller for induction machines. The proposed control approach is motivated by the fact that developing an appropriate mechanical model of such induction machines is a challenging task. Since our proposed control methodology is only on the basis of measured data, the controller design does not require any information about the model of the mechanical part. The control of motor drive is often based on sensorless field-oriented control techniques because of their advantages such as noise and cost reductions and high reliability. Hence, we assume here that measurements used for the controller design are collected using an estimator based on the electrical equations of the induction machine. A practical application to control the speed of an induction machine is presented to validate and demonstrate the efficiency of the proposed method.

Sliding mode control applied to the inner loop regulation of a faulted six phase induction machine (6PIM)

In this paper, sliding mode control (SMC) is applied to regulate the dq axis currents of a 6 phase induction machine (6PIM). This strategy presents a good alternative in power electronics for electrical drives because of its dynamic properties and its high robustness. The design of the sliding mode control law, defined from the healthy mode model, is based on the linear feedback with switched gains approach. With this strategy, the control voltages are smooth and guarantee the stability of the control loop regarding the faulted condition of the 6PIM. Experimental results assess the robustness of the proposed sliding mode control compared to traditional Proportional-Integral algorithm.

A DSP-Based Implementation of a Nonlinear Optimal Predictive Control for Induction Machine

In this paper an optimal nonlinear multiple-input multiple-output (MIMO) predictive control approach is applied to control the flux and the rotor position of a three-phase induction machine. For this, a nonlinear induction machine model is elaborated in the synchronous d-q frame rotating with electromagnetic field. Then, the outputs are predicted over a predefined prediction horizon. The design of the proposed predictive control law is based on the minimization of a quadratic criteria. The control voltages are being smooth and guarantee the stability of the control loop regarding parameter variations. Simulations and experimental results highlight the robustness of the proposed nonlinear optimal predictive control

Comparison between fuzzy logic and sliding mode control applied to six phase induction machine positioning

This paper presents the design and application of the fuzzy logic and the sliding mode controls associated with field oriented control in order to obtain a high precision positioning of a six phases induction machine (6PIM). The two techniques are first presented. Then, to validate experimentally the efficiency of the two methods, an advanced test bed is used.

Synchronous and Induction Wind Power Generators as Renewable Power Energy Sources

Nowadays, renewable power energy sources are a demanding research area. Due to the high prices of fossil combustible and to the increase of energy consumption, a considerable attention is drawn in alternative energy sources such as wind-based generators. This paper presents the state of the art of recent research in the field of synchronous and induction wind powered generators. In this way, different configurations of modern generators with their control are described. The architecture of the different schemes used to produce the electrical energy using wind turbine are presented from both electrical machine topology and control strategy points of view. Then, synchronous and induction generator drives are treated in detail with their related power electronic control-based systems.

Model-Free Controller Tuning Based on DFT Processing: Application to Induction Motor Drives

In this paper, we present a new approach based on discrete Fourier transform (DFT) analysis for controller tuning of the closed-loop system with unknown plant. The DFT analysis is used to process the closed-loop measurements collected online to derive the frequency response of an initial closed-loop system that does not provide a good performance. Based on the closed-loop frequency response data, we propose two methods for tuning PID controller parameters according to some desired closed-loop performance specifications. The proposed approach can be applied online because the closed-loop system does not need to be stopped for data collection. The tuning problem of rotor speed controllers of electric drives, is chosen as an example to experimentally validate our proposed method. Specifically, we are interested here in the control of an induction motor. The availability of high-performance computational and storage facilities greatly simplifies the collection of measured data used for controller tuning. The experimental results presented in this paper demonstrate the efficacy and usefulness of the proposed control design method in many industrial applications.

Measurement-based control approach for tuning PID controllers: application to induction machines

This paper presents an approach to design proportional - integral – derivative controllers for induction machines using measurements. Most control methods developed for induction machines are generally based on mathematical models. Due to complex dynamics of induction machines, identified models are often unable to perfectly describe their behaviour. Thus, the system performance will be limited by the quality of the identified model. Hence, developing control methods that do not require the availability of system model is advantageous. Here, we propose an approach that uses the frequency response data to directly design controllers. The main idea here is to find controller parameters so that the closed-loop frequency response fits a desired frequency response. Its main advantage is that errors associated with the modelling process are avoided. Moreover, the control design process does not depend on the order and complexity of the plant. A practical application to induction machines illustrates the efficac...

Control position of a faulted Six Phase Induction Machine (6PIM) using sliding mode control

The main goal of increasing the number of phases in an induction machine is to ensure its performance in all the operating modes such as normal, disturbed and faulted settings. When the induction machine is working under a faulted mode such as one or more phases are missing, this leads to a high torque oscillations and bad tracking behaviour. Designing a suitable control design such as sliding mode control is a challenge task. This controller, with a suitable transformation of the original model matrix, has the task of reducing the torque oscillations and overcome all fluctuations of the dynamic behaviour of the machine in faulted mode by removing the tracking steady-error. This paper presents the design and the application of the sliding mode controller associated with vector control method for controlling the rotor position shaft of the six phase induction machine (6PIM).