A comparative study on transmission performance of multi‐stage wireless power transfer systems using SPS compensation and LCC compensation

Summary The new multi‐stage wireless power transfer (WPT) systems based on series–parallel–series (SPS) and inductor–capacitor–capacitor (LCC) compensations (SPS‐WPT and LCC‐WPT) are characterized by constant output current and high transmission efficiency. To obtain applicable conditions and performance differences of these two systems, their output characteristics have been studied by theoretical derivation and experimental verification. First, the equivalent models of double‐stage SPS‐WPT and LCC‐WPT systems have been built. Second, comparative analysis of two key compensation components that affect the output performance of the two systems has been completed. Third, the influence of each stage load and coupling conditions on the output performance of the two systems has been further analyzed and compared. Finally, output performance of the two systems has been tested and compared on a newly built experimental platform. Experimental results show that the output power and transmission efficiency of the SPS‐WPT system reach 180 W and 80.39% with offset of 20 mm, which is more suitable for high power applications with low and fixed coupling condition. In addition, the output power and transmission efficiency of the LCC‐WPT system reach 127 W and 85.92% with offset of 10 mm, which is more suitable for high efficiency applications at medium and variable coupling conditions. A comparative study of multi‐stage constant current wireless power transfer systems using SPS compensation and LCC compensation have been presented in this paper. The effects of compensation circuit parameters, load, and mutual inductance fluctuation on output characteristics are analyzed by theoretical derivation, calculation, and experimental verification.