Analysis, design, and optimisation of an LCC/S compensated WPT system featured with wide operation range

Abstract

Wireless power transfer (WPT) offers the advantages of convenience, safety, low-maintenance, high reliability, andstrong adaptability to the environment. This study proposes a design method to help LCC/S compensation topology achievezero voltage switching (ZVS), which helps improve the efficiency of the system. The optimisation design of the magneticcoupling structure is conducted first via the finite element simulation software, ANSYS Maxwell. Planar circular coil offerssuperior comprehensive performance over other structures and is thus utilised in this study, which theoretically analyses theprimary characteristics of LCC/S (primary inductor-capacitor-capacitor, secondary series) compensation topology. The studymakes an in-depth comparison of two methods for achieving ZVS, adjusting secondary series compensation capacitance, andmaking a primary T-type network asymmetric. The conclusions of the theoretical analysis indicate that making a primary T-typenetwork asymmetric is the most suitable method for the proposed WPT system. A 400 W prototype was built, and it consistentlyachieved ZVS operation within the entire load range (5 50 O). The highest power transfer efficiency (PTE) achieved by theprototype was 92.9%, and the PTE was consistently above 88% within the entire power range (50 400 W).