Patent ID: 9263979
Filing Date: 2016-02-16
CPC Classification: H02P

Claim Text:
1. A method of conducting smooth motor startup, the method comprising: operating a motor in an open loop control scheme at startup by applying error commands to current regulators from a feedback loop, which takes current information derived from a control signal output from the current regulators to an Inverse Park transformation and a speed reference-derived ramping angle command to generate the error commands at serially arranged Clark and Park transformations, the speed-derived ramping angle command being received at the Inverse Park and Park transformations; operating the motor in a closed loop sensorless control scheme at a time after startup by applying the error commands to the current regulators from the feedback loop, which takes current information derived from the control signal output from the current regulators to the Inverse Park transformation and actual rotor speed and angle estimates to generate the error commands at the serially arranged Clark and Park transformations, the actual rotor angle estimate being received at the Inverse Park and Park transformations and the actual rotor speed estimate being received at one of the current regulators; and transitioning between the open loop control scheme and the closed loop control scheme by reducing a difference between an estimated rotor angle of the motor and a commanded ramping angle of the motor.