Energy-Efficient and Fault-Tolerant Control of Multiphase Nonsinusoidal PM Synchronous Machines

This paper presents development of energy-efficient and fault-tolerant control of multiphase nonsinusoidal PM synchronous machines by making use of the Hamiltonian of optimal control theory. An analytical solution for the optimal linearization control is derived in a closed form that eliminates machine torque ripples, maximizes machine efficiency, and defers output voltage saturation for nonconstant operational torque and speed. The controller can achieve voltage-to-torque linearization even for faulty motors with open-circuited phase(s) making it suitable for high-risk applications. This study is complemented by presenting an optimal indirect-torque control scheme based on internal current feedback loop with finite bandwidth. Simulation and experimental results are appended to underpin the performance of the energy-efficient and fault-tolerant controller.