Investigation of resonant tank topologies performance in wireless power transfer applications

Wireless power transfer (WPT) has been developed as a suitable candidate for energy transfer in various applications, recently. Resonant tank is the main passive part of such systems and various topologies are introduced to improve WPT systems performance. Characteristics of these topologies definitely affect system overall performance. Therefore, each topology's specification and performance indexes should be evaluated and compared to choose a suitable one for a required application. In this paper, the characteristics and behaviour of voltage gain, input admittance and efficiency of well-known compensation topologies are thoroughly investigated for the first time. By calculating the voltage gain sensitivity, some analysis are performed on typical compensation including SS, SP, LCL-S, LCL-P, LCC-S, LCC-P and double-sided LCC under key parameter variations such as load resistance, switching frequency and coupling coefficient. In addition, by introducing a new formula for efficiency, the effect of resonant tank elements on efficiency is studied analytically which has not been performed before. In order to evaluate the theoretical analysis, the performance of all compensation topologies is investigated in MATLAB environment. By employing prototype SS and SP compensated inductive power transfer (IPT) test-bed system, some experimental verification are performed and the results confirm the analytical and numerical simulation findings.