Wideband Backforward-Drivability Motor Drive Based on Fast Current Control of Geared SPMSM

This paper achieves the wideband backforward-drivability motor drive of Geared surface permanent magnet synchronous motor (SPMSM) modelled as a two inertia resonant system. The control bandwidth of a resonance-ratio-control-based torsion torque controller cannot be broadened due to weak robust stability against gear stiffness variation. To solve the problem with regard to the robust stability, the control bandwidth of the current control system is broadened by using the low-latency space vector pulse width modulation, integrator-less regulators, and accurate parameter identifications. This paper achieves 4 kHz bandwidth of current control and realizes the wideband torsion torque control based on “final integrator cascade scheme.” Even though the gear stiffness variation occurs, the control bandwidth of the outer torsion torque control is set to high frequency. As a result, this paper enhances the backforward-drivability of the geared SPMSM. The experimental results of the current control system and the simulation results of backforward-drivability control confirm that the torsion torque control with fast current control is effective.