Operation region of class E resonant inverter for ultrasonic transducer

Piezoelectric ceramic transducers (PCTs) are used as the vibration sources for the ultrasonic cleaner. However, PCTs have a narrow operational region and sensitive to load variation. This paper presents the operational region of a class E resonant inverter for extending the PCT operational range. The class E resonant inverter is operated at the suboptimum mode to minimize switching losses of the power switch. The power switch operates the zero voltage switching (ZVS) operation by using the presented condition. Simulation result shows that the frequency response of the class E resonant inverter with the PCT and operational region, compare a current and voltage output at the operational frequency (fm) and resonant frequency (fr) of the class E resonant inverter. Finally, the presented system is verified by experimental result. The PCT can generate the ultrasonic wave for the ultrasonic cleaner at the operational region. The class E resonant inverter works on ZVS operation while the operated duty cycle is regulated.