Design Enhancement of a Power Supply System for a BLDC Motor-Driven Circuit with State-of-Charge Equalization and Capacity Expansion

This paper presents a design enhancement of a power supply system for brushless dc (BLDC) motor-driven circuits with state-of-charge (SOC) equalization and capacity expansion. The proposed design incorporates different types of battery as the input power, in which SOC equalization and battery modularization are both concerned. Through the proposed control strategy, it achieves the SOC balance among batteries, avoiding damages caused by overdischarging. Meanwhile, considering that BLDC motors require multiple input sources, this study develops an integrated dual-output converter that exhibits the features of both forward converter and flyback converter. To validate the feasibility of this proposed method, different test scenarios have been evaluated via the prototype completed in the laboratory. Experimental results reveal that this approach is capable of providing consistent outputs under different load conditions along with the achievement of SOC equalization among batteries, thereby serving as beneficial references for BLDC circuit applications.