Control strategy of post-fault operation in dual inverter-fed, PMSM considering zero sequence and back-emf harmonic

The motivation for this paper is to present the capability of the dual inverter open-end winding of handling failures and continue to operate when failure occurs. The analysis of before failures, after failures and their effects on the system, is crucial. If nothing has been planned, the after effect of the failures may result in costly damage and may lead to another fault. The situation is undesirable and should be avoided or at least there should be a fault tolerant function to deal with such failures. Therefore, this paper will focus on the control scheme under an open-circuit phase fault for dual inverter-fed, permanent magnet synchronous motors with non-sinusoidal back-EMFs. The inverters are connected to both ends of the machine winding but use only one power source, thus a path for zero sequence currents to circulate in the motor winding is present. The feasibility of the drive during healthy and faulty conditions will be verified using experimental test. The phase currents, the zero sequence current, and the SVPWM strategy of the post-fault configuration are are presented.