Fault-Tolerant Control of Half-Centralized Open-End Winding Motor Drive System Considering Open-Circuit Faults

In this article, a fault-tolerant control method is designed for half-centralized open-end winding (HCOW) motor drive system with open-circuit fault. In the HCOW drive system, each mover can output fluctuated thrust and the system thrust should keep constant. This will provide additional degree of thrust freedom, which may lead to less system copper loss or higher torque (thrust) output capacity. The proposed fault-tolerant control method includes two fault current distributors and one voltage distributor. The fault current distributor I is designed for the common-leg fault based on the Lagrange loss minimization principle. The fault current distributor II is designed for the independent-leg fault based on the fundamental frequency phase loss minimization principle. The voltage distributor is designed to distribute the voltage demand into remaining inverter legs. The system copper losses and the thrust output capacity of the different methods are analyzed. Compared with the conventional method, the proposed tolerant method can reduce the system copper loss and increase the thrust output capacity. Finally, the proposed fault-tolerant control method has been verified by experimental results.