Electronic valve actuator with predictive self-calibrating torque controller

Abstract

An electronic controller of a valve actuator predictively calculates motor inputs that will cause the actuator to apply desired forces or torques to a valve. A force/torque sensor of the actuator measures applied force or torque at the motor output and/or valve to verify the applied force or torque and enable updating of calibration settings as needed. Upon failure of the force/torque sensor, embodiments continue predictive operation without sensor verification or calibration updates. Upon failure of the predictive control, embodiments continue valve actuation under reactive control via the force/torque sensor. Connection to a calibration valve simulator enables embodiments to perform an initial self-calibration using the force/torque sensor of the actuator. The motor can be a variable frequency driven AC motor or a DC motor. The calibration can incorporate mechanical properties of an actuator gear train.