Adaptive grey control for hybrid resonant driving linear piezoelectric ceramic motor

This paper presents an adaptive grey control (AGC) system for a linear piezoelectric ceramic motor (LPCM) driven by a newly designed hybrid resonant inverter. First, the motor configuration and the driving circuit of an LPCM are introduced, and its hypothetical dynamic model is described briefly. The hybrid resonant drive system has the merits of high voltage gain from a parallel resonant current source and the invariant output characteristic from a two-inductance two-capacitance (LLCC) resonant driving circuit. Since the dynamic characteristics and motor parameters of the LPCM are highly nonlinear and time varying, an AGC system is therefore investigated based on the principle of computed torque control and grey method to achieve high-precision position control under wide operation range. In this control system, a grey uncertainty predictor is utilized to estimate the lumped uncertainty on line to relax the requirement of the unknown uncertainty in the design of a computed torque position controller. In addition, the effectiveness of the proposed drive and control system is verified by numerical simulations and experimental results in the presence of uncertainties.