Digital control of a high-voltage (2.5 kV) bidirectional DC-DC converter for driving a dielectric electro active polymer (DEAP) based capacitive actuator

This paper presents a digital control technique to achieve valley switching in a bidirectional flyback converter used to drive a dielectric electro active polymer based incremental actuator. The incremental actuator consists of three electrically isolated, mechanically connected capacitive actuators. The incremental actuator requires three high voltage (~2.5 kV) bidirectional DC-DC converters, to accomplish the incremental motion by charging and discharging the capacitive actuators. The bidirectional flyback converter employs a digital controller to improve efficiency and charge/discharge speed using the valley switching technique during both charge and discharge processes, without the need to sense signals on the output high-voltage side. Experimental results verifying the bidirectional operation of a single high voltage flyback converter are presented, using a film capacitor as the load. Energy efficiency measurements are provided.