A Mixed Flux Coupler and Dual-Path Parallel Compensation Based Rotating Wireless Power Transfer System Integrated With Rotational Speed Monitoring Function

A rotating wireless power transfer system based on a mixed flux coupler and dual-path parallel compensation is proposed in this paper. It can achieve stable and efficient wireless power transmission as well as accurate speed monitoring without adding an additional excitation, solving the problems of voltage instability and low efficiency in existing solutions. First, the system topology and working principle are presented. Then, the working characteristics of the mixed flux coupler are analyzed and optimized. The power, efficiency, and voltage gain formulas are derived for the system based on a dual-coupled inductor– capacitor–capacitor-series (LCC-S) compensation. Based on these theories and the functions that need to be achieved, a number of key design criteria are discussed. Practical experiments on rotating wireless power transmission, speed measurement, and dual-load interference have been carried out. The experimental results show that the proposed system can achieve accurate speed monitoring and stable wireless power transmission. The maximum power of the system can reach 163.59 W, and a maximum efficiency of more than 80% can be achieved. The proposed technique has the potential to significantly contribute to the further development of wireless power transfer technology for rotating machines, such as wind turbines, machining equipment, and robot joints.