Piezoelectric actuator type control device for capacitive loads

A device for controlling at least one piezoelectric actuator driven electronically using a control computer, comprising a first stage for generating a DC voltage including a first voltage converter circuit for delivering said DC voltage over a DC supply bus provided with a first supply line and with a second supply line, to each of which an electrical potential is applied with a view to obtaining a voltage on the DC supply bus, and a second, switched-mode power supply stage, connected to said DC supply bus, including a second voltage converter circuit supplied with said DC voltage so as to generate at least one variable excitation voltage for said at least one piezoelectric actuator under the control of said control computer, said device being characterized in that said second voltage converter circuit includes two half-bridges of switches connected in parallel to the terminals of a bus capacitor which is connected to the first supply line and to the second supply line of said DC supply bus, said control computer being suitable for controlling each of the half-bridges of switches both independently, in a first control configuration in which the two half-bridges of switches are controlled individually so as to deliver a respective excitation voltage varying between zero and a positive maximum value to at least one piezoelectric actuator that is capable of being connected at the output of each half-bridge of switches, respectively, and jointly, in a second control configuration in which the two half-bridges of switches are controlled together as a full bridge so as to deliver an excitation voltage varying between a negative minimum value and said positive maximum value to a piezoelectric actuator that is capable of being connected between the respective midpoints of the two half-bridges of switches.