Patent ID: 8459607

Claim:
A control device for a control valve, having an opening detecting means configured to detect an opening of a control valve driven by an electric actuator, a target opening setting means configured to set a target opening of the control valve, and an actuator control means configured to control the electric actuator to eliminate a deviation between the opening detected by the opening detecting means and the target opening set by the target opening setting means with a feedback control in accordance with the deviation, the control device comprising a power supply interrupting means configured to interrupt power supply to the electric actuator in the case where a predetermined necessary condition containing at least a condition for the absolute value of the deviation to be smaller than a first predetermined value is satisfied; wherein the control valve is biased to obtain a predetermined opening in a state where the electric actuator does not generate a driving force; and wherein the predetermined necessary condition further contains a condition for the absolute value of a deviation between the detected opening or the target opening and the predetermined opening to be smaller than a third predetermined value.