Simulation of sensor less speed control of PMSM based on FOC method with MRAS adaptive speed estimator

The PMSM motors are increasingly playing an important role in modern motor drives. A shaft encoder or sensor connected to the shaft of the motor provides feedback required for controlling torque and speed to the PMSM. So many motor drives are not abiding by the application of this feedback device because of their reliability concerns, price, and space and weight limitations. This paper analysis the adjustable current model in which PMSM itself acts as reference model, with the parameter of speed revolution adjustable for the sensor less speed control of PMSM, a model reference adaptive system mechanism is used. The control scheme is simulated in the Matlab/Simulink software environment. The simulation result shows that the speed of rotor is estimated with high precision and response is considerable fast. It also shows that the whole control system is effective, feasible and simple.