Fuzzy logic controller of PMSM for sensorless drives

This paper proposes Fuzzy Logic Controller scheme in sensorless (PMSM) drives based on fundamental excitation. Fuzzy Logic Control (FLC) is suitable for a controller design when the system is difficult to model mathematically due its complexity, nonlinearity and imprecision. Especially for sensorless drives of PMSM which uses the complex estimator's equations and adaptation mechanism. Fuzzy Logic Controller is widely used in high performance drives to obtain precise speed control irrespective of load disturbances and parameter variations. Most of the sensorless techniques are based on the voltage equations of the PMSM and the information of the terminal quantities, such as line voltages and phase currents. By using this information, the rotor angle and speed are estimated directly or indirectly. This paper presents the sensorless drives based on differential of d-q voltage and current equations, which are manipulated from the fundamental excitation. The elimination of speed sensor in PMSM drives specifically using Fuzzy Logic Controller, will reduce the overall cost, size and complexity without degrading the system performance. The proposed method is simulated by using MATLAB/Simulink. The simulation results of the sensorless PMSM drives are successfully achieved. The applied technique shows good speed regulation and proves that PMSM can be controlled for forward or reverse operating conditions as well as for load disturbance.