Patent ID: 8523511

Claim:
A variable geometry turbine controller for operation with a variable geometry turbine including a variable geometry member located in an inlet of the turbine, an actuator operative through a range of actuation positions to move the variable geometry member through a first range of variable geometry member positions that extends between a hard-stop closed position and a hard-stop open position, and that includes a smaller, second range of variable geometry member positions intermediate the hard-stop closed position and the hard-stop open position corresponding to desired flow conditions, and a sensor configured for sensing actuation information indicating the actuation position of the actuator, comprising: a memory device operative for reading and writing information; and a processing device operative with the memory device to write and read positional information, including a transfer function relating sensed actuation information to actual variable geometry member positions throughout the second range of variable geometry member positions; wherein the processing device is operative to intermittently direct the actuator to actuate the variable geometry member to the hard-stop closed position, to read the actuation information sensed by the sensor device with the variable geometry member at the hard-stop closed position, and to re-establish the transfer function based on sensor information read with the variable geometry member at the hard-stop closed position.