Control of flexible drive with PMSM employing forced dynamics

Forced dynamics control principles are exploited to develop control algorithms for electric drive with PMSM and flexible couplings. The controller is of the cascade structure, comprising an inner speed control loop, which respects the principles of vector control and requires a load torque estimate and an outer position control loop, which is designed to control the PMSM rotor or load angle in the presence of the vibrations due to flexible coupling including an external load torques. Computation of PMSM stator voltage is based on novel algorithm exploiting forced dynamics control. Derived control laws require the estimates of the load torque and its derivatives estimated in the set of observers. Control algorithm is verified by simulations and preliminary experiments indicating good agreements with theoretical predictions, therefore further experimental verification of the designed control algorithm is recommended.