Soft Switching Based Design of a Single-Stage Wireless DC Motor Drive System for Typical Mechanical Loads

This paper introduces a wireless DC motor drive system designed to overcome wire cut issues during rotation. The system employs a dual-bridge structure that integrates power supply and motor control functions, eliminating the need for a separate motor drive inverter. A control strategy is proposed, which involves a fixed primary-side frequency and duty cycle, along with a fixed secondary-side off-time. This strategy effectively eliminates the requirement for communication between the primary and secondary sides, while ensuring soft switching for active rectifiers across various load conditions. In addition, the paper investigates the impact of frequency deviation on the inverter's soft switching behavior, establishing a parameter boundary for achieving soft switching. By considering the speed-torque relationship for different mechanical loads, the paper offers valuable guidelines for designing single-stage wireless DC motor drive systems. To validate the analysis, a 200W prototype is constructed, and its performance is evaluated. The prototype achieves a maximum DC/DC efficiency of 96.56%, providing practical evidence in support of the presented findings.