Novel Compensation Parameter Design Methodology and Maximum Efficiency Tracking Control Strategy for Inductive Power Transfer System

This paper presents a novel compensation parameter design methodology and maximum efficiency tracking (MET) control strategy for inductive power transfer (IPT) system with an inductance and double capacitance-series (LCC-S) compensation topology. The compensation parameters of a conventional IPT converter are designed for the required output voltage by considering the fluctuation ranges of the battery voltage and coupling coefficient, but without considering the efficiency characteristics of the IPT converter. Additionally, the IPT system efficiency fluctuates with the load, because the battery equivalent resistance continuously changes according to the state-of-charge. To address these problems, this paper presents a compensation parameter design methodology based on a loss analysis of the IPT converter. The losses of the transmitter and receiver in the IPT converter with the optimal compensation parameters are compared and analyzed according to the load. Based on these analyses, a control strategy is proposed for tracking the maximum efficiency according to the load without real-time communication. To validate the proposed compensation parameter design methodology and maximum-efficiency tracking control strategy, a 1.85 kW experimental prototype is configured.