Dual Battery Powered Drive System Using an Open-End Winding Brushless DC Motor

Dual inverter-fed open-end winding (OEW) motor drive is one of the new promising solutions, which has several advantages over standard three-phase drives such as multilevel voltage output, lower DC link voltage, higher efficiency and better fault tolerant capability. In this paper, such an approach has been used for brushless DC motor (BLDCM) drive system, which has significant advantages for low-power electric vehicles. At the first, a possibility of forming of basic vectors in the structure of OEW BLDCM drive is shown for two cases of discrete switching of armature windings with 120-degree and 180-degree switches conductivity. Then, for a simpler 120-degree commutation mode, a control system was developed, which is being characterized by a change in the switching of the two inverters in different modes of the electric drive system operation. In order to increase energy efficiency, a PWM is applied only to one of the inverters. In addition, a simple strategy of charge equalization for two batteries has been developed. The effectiveness of the proposed solutions is confirmed by computer simulation in the Matlab/Simulink.