Patent ID: 7211984
Filing Date: 2007-05-01
Classification: F02N,H02P

Abstract:
1. A method of starting a permanent magnet machine controlled using one or more position detection modules that detect a position of a rotor of the machine, said method comprising: sensing a machine stator voltage in a stationary reference frame; estimating an initial speed of a rotor of the machine based on said sensed voltage; and initializing at least one of the one or more position detection modules based on said estimated initial speed; said sensing, estimating and initializing performed while at least one synchronous current regulator of the machine is disabled; wherein said initializing comprises: wherein a low-speed position detection module is initialized, said method further comprising determining a polarity of an initial position of the rotor in accordance with: where ω represents rotor speed, V d s represents the sensed voltage in a d-axis, V q s represents the sensed voltage in a q-axis, and λ PM represents magnetic flux linkage.