Abstract: A self-sensing actuator without independent sensor is used to measure displacement of a piezoceramic micromotion worktable, and a displacement self-sensing control system is made. For a piezoceramic actuator, the free charges on the wafer surfaces contain the displacement information of the actuator, thus based on the integrator circuit, the displacement self-sensing for the piezoceramic actuator is proposed and also the integrator circuit is designed. This self-sensing method greatly facilitates circuit adjustment, easy to acquire sensitive signal and avoids the shortcoming of impedance mismatching met in bridge circuit. The self-sensing displacement is the feedback signal of control system of piezoceramic micro-motion worktable. In order to improve the static and dynamical performance of the piezoceramic micro-motion worktable, the compounding control method by combining feedforward control and feedback control is designed. The comparison experiments are performed in order to contrast the self-sensing compounding control with other control methods, such as the forwardfeed control, the PID control with independent sensor and the compounding control with independent sensor. The experimental results show that self-sensing compounding control has the same good performance of compounding control with independent sensor.

Key words: Compounding control, Integrator, Micro-motion worktable, Piezoceramic actuator, Self-sensing