A low-power, self-tuning resonant driver for generating sinusoidal pulse trains with piezoelectric element loads

A topology, control algorithm and self-tuning calibration procedure are presented for a two stage resonant driver that generates precise sinusoidal pulse trains for piezoelectric loads. The power stage consists of a PWM Boost followed by a variable frequency half bridge resonant inverter. The resonant tank consists of three inductors engaged on demand and a single capacitor. An automated calibration procedure is run to characterize the piezoelectric load and compensate for its nonlinear behavior. Experimental results of the laboratory prototype running at frequencies of 100 to 400 kHz with maximum amplitude of 200 Vpp validate the control algorithm and presented calibration procedure.