State space torque observer based control of permanent magnet synchronous machines

This paper presents a state space based torque observer control for permanent magnet synchronous machine (PMSM) speed drive. A simple control algorithm is obtained by performing field orientation through state feedback. The latter, needs the measurement of the entire state vector, which is in practice impossible due to the presence of the unknown load torque. To overcome this problem, a linear observer is proposed to estimate this torque allowing the implementation of the state feedback control. To show the effectiveness of our control approach, simulation and DSP based experimental results are presented.