LCCL series resonant inverter for ultrasonic dispersion system with resonant frequency tracking and asymmetrical voltage cancellation control

This paper presents a high efficiency LCCL series resonant inverter for ultrasonic dispersion system with resonant frequency tracking and asymmetrical voltage cancellation control. With the proposed control, the operating frequency of the inverter is automatically adjusted to track the resonant frequency under load parameter variation due to surrounding condition. The zero-voltage switching (ZVS) is maintained throughout the operation. The output power is controlled using the asymmetrical voltage cancellation (AVC) technique. A full-bridge hardware prototype is constructed and the control algorithm is implemented using an STM32F4 microcontroller. Computer simulation and hardware experiment are provided at an operating frequency range of 37-42 kHz and the output power of 30-125 W.