Comparison of voltage-source resonant driving schemes for a linear piezoelectric ceramic motor

Linear piezoelectric actuators are innovative manipulators that have shown a high potential in applications requiring operation within the submicrometer or even the nanometer range. The driving principle of a linear piezoelectric ceramic motor (LPCM) is based on the ultrasonic vibration force of piezoelectric ceramic elements and mechanical frictional force. Therefore, its dynamic model is complex, and the motor parameters are time varying due to increasing temperature and changing motor drive operating conditions, so that it is difficult to design a suitable driving strategy for the LPCM. This paper presents a comparative study of three voltage-source resonant driving schemes, including an inductance-capacitance (LC) resonant inverter, an LLCC-resonant inverter, and an LC-resonant inverter with energy feedback for the LPCM. The effectiveness of the reported driving strategies is verified by numerical analyses and experimental results under the variation of loads. By way of experimental validation, the newly designed LC-resonant inverter with energy feedback for driving the LPCM possesses good performances of high voltage gain and invariant output characteristic under different operating conditions.