Circuit and Method for Controlling a Piezoelectric or Electrostrictive Actuator

摘要

A circuit and/or a corresponding method for controlling a piezoelectric or electrostrictive actuator (P) have a series-connected driver stage (G) which provides a control signal which is used to drive the piezoelectric actuator (P). A reference capacitor (M), which is used to measure a charge (qP) of the actuator (P), is serially connected to the actuator (P). The reference capacitor (M) is used as a series capacitor in order to measure the actuator charge (q_A(T)=q_P(t)) of the piezoelectric actuator. The output variable is a voltage which is proportional to the actuator charge. The voltage is guided to an A/D-converter and is processed further in a digital manner or guided directly to a analogue controller.