Controlling Speed of a Permanent Magnet Synchronous Machine using Closed Loop Control Scheme

Abstract

In this article, speed control of PMSM is analyzed with closed-loop control scheme. The controller used here plays an important role by minimizing the speed deviation and hence the steady state error becomes zero. To control the speed of such drive system, voltage and frequency are changed without disturbing the ratio of voltage and frequency i.e., the ratio is maintained constant. The proposed technique works on the reduction of peak overshoot, rise time and settling time. It can be seen from the results obtained that the closed loop model has better accuracy than open loop control system model. A transformation block is used to convert the d-q axis into abc axis. All the MATLAB/Simulation results are discussed thoroughly with respect to their corresponding characteristics. The changes in the stator current and respective torque are observed with respect to the change in speed and it is analyzed in this paper.