In this study, we investigated the capability of harvesting the electrical energy from mechanical vibrations in a dynamic environment through a ''cymbal'' piezoelectric transducer. Targeted mechanical vibrations lie in the range of 50-150 Hz with force amplitude in the order of 1 kN (automobile engine vibration level). It was found that under such severe stress conditions the metal-ceramic composite transducer ''cymbal'' is a promising structure. The metal cap enhances the endurance of the ceramic to sustain high loads along with stress amplification. In this preliminary study, the experiments were performed at the frequency of 100 Hz on a cymbal with 29 mm diameter and 1 mm thickness under a force of 7.8 N. At this frequency and force level, 39 mW power was generated from a cymbal measured across a 400 k resistor. A DC-DC converter was designed which allowed the transfer of 30 mW power to a low impedance load of 5 k with a 2% duty cycle and at a switching frequency of 1 kHz.
A double-sided LCLC-compensated capacitive power transfer (CPT) system is proposed for the electric vehicle charging application. Two pairs of metal plates are utilized to form two coupling capacitors to transfer power wirelessly. The LCLCcompensated structure can dramatically reduce the voltage stress on the coupling capacitors and maintain unity power factor at both the input and output. A 2.4-kW CPT system is designed with four 610-mm × 610-mm copper plates and an air gap distance of 150 mm. The experimental prototype reaches a dc-dc efficiency of 90.8% at 2.4-kW output power. At 300-mm misalignment case, the output power drops to 2.1 kW with 90.7% efficiency. With a 300-mm air gap distance, the output power drops to 1.6 kW with 89.1% efficiency.Index Terms-Capacitive power transfer, electric vehicle charging, LCLC compensation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.