Mitigation of Frequency Splitting Phenomena Using a Matching Capacitor in Wireless Power Transfer System for Automated Guided Vehicle

An Automated guided vehicle (AGV) that transmit high power requires power to be transmitted with high efficiency to lower power loss. However, if the coupling coefficient is increased to increase power transfer efficiency, frequency splitting occurs, which adversely affects output power and system stability. In this paper, a method to mitigate frequency splitting in a magnetic resonant wireless power transfer (WPT) system for 1.5 kW AGV is proposed. Frequency splitting phenomena are alleviated by using the matching capacitance of the transmitter selected based on the analysis of the phase and reactance of the input impedance when the frequency is split. The use of the selected capacitance results in a stable phase of input impedance, and also improves output power capacity. The proposed method is verified by circuit simulation.