Arnaud Sivert

Determination of Scaling Factors for Fuzzy Logic Control Using the Sliding-Mode Approach: Application to Control of a DC Machine Drive

In this paper, a new approach to define the optimum values of the scaling factors for a fuzzy logic controller, based on the sliding mode theory, has been proposed. Indeed, these factors are chosen in such a way that the trajectory in the phase plane is always attracted by the main diagonal of the fuzzy matrix and slides on this line. This approach was first tested in simulation to control the position of a permanent-magnet direct-current machine drive and then implemented on a low-cost 16-bit microcontroller. Furthermore, the scaling factors are tuned in function of the distance between the reference and the output in such a way as to cope with the discretization of the lookup table stored in the memory of the microcontroller. This algorithm has been successfully applied on an advanced test bed, which allows mechanical configuration changes

Robust control of an induction machine drive using a time-varying sliding surface

In this paper, a variable structure position control law for an induction motor with a field-oriented control strategy is proposed. The algorithm, based on a time-varying switching line, guarantees the existence of the sliding mode since the beginning of the shaft motion. Indeed, the switching line is initially designed to pass through the initial representative point and subsequently moved towards a predetermined desired surface via shifting. By this mean, the reaching phase is eliminated and the motor behavior is insensitive to unknown mechanical configuration changes. The algorithm has been tested in simulation for evaluated the robustness capacities.

Sensorless position control of six-phase induction machine using fuzzy-PI system

This paper presents a new approach to the sensorless position control of six-phase induction machine (6PIM). A fuzzy-PI (FPI) system has been employed to estimate the rotor position and avoid using mechanical sensor. Also, high-accuracy positioning of a 6PIM rotor can be obtained using such FPI system in model control loops. The input-output scale factors of all FPI systems are tuned using genetic algorithms to achieve better results. The proposed scheme is validated through experimental results, and it is demonstrated that an FPI configuration is attainable to implement rotor position estimation and control in 6PIM drives.

Efficient Field Oriented Control with power losses optimisation of a six-phase induction generator for wind turbines

The aim of this work is to propose an efficient vector control for power losses optimisation of a squirrel cage six-phase induction generator (SC6PIG). This method, suitable for variable speed wind energy conversion system (WECS), allows the increase of the generator efficiency whatever the power operating points. This efficient control method is based on Field Oriented Control (FOC) associated to an electrical power losses minimisation strategy. Experimental tests are realized on a laboratory test bed based on low speed 24 kW SC6PIG. Theoretical results are presented and experimental results for different operating points are compared with a conventional vector control method to prove the effectiveness of the proposed method. Indeed, experimental results shows that the proposed method for light power loads can improve significantly the efficiency of the SC6PIG.

Fault tolerant control of six-phase induction generator for wind turbines

In this paper, simulation and experimental results of a fault tolerant of a squirrel cage six-phase induction generator (SC6PIG) are presented. The proposed generator, suitable for grid connected multiphase wind energy generating system, is composed of a 24kW SC6PIG prototype connected to a full scale back-to-back converter structure. The aim of this paper is to validate experimentally the model of the whole fault tolerant control system based on the Field Oriented Control (FOC) scheme. Simulation and experimental responses are compared for the same generation profiles.

Efficiency optimization on vector controlled six-phase induction motor in healthy and faulted mode

This paper introduces a new technique for efficiency optimization of 6-phase induction motor (6PIM) drive, based on fuzzy online search control (SC) method. The modified SC algorithm does not require extra hardware and is insensitive to motor parameters. The results are compared to classic loss model control (LMC) efficiency optimization algorithm in healthy and faulted operational mode due to up to three stator open phases. The experimental results obtained on a dedicated test-bed validate the efficiency of the proposed method.