Patent ID: 9559623
Date: 2017-01-31
CPC Classifications: H02P

Claim:
1. A method of controlling an electrical machine including a stator having a core and a plurality of windings, and a rotor disposed adjacent to the stator to interact with the stator, the method comprising: configuring an amplitude value and frequency values of a three-phase alternating current (AC) voltage startup signal having an amplitude and a frequency, the three-phase (AC) voltage startup signal being distorted from a sinusoidal voltage; providing the three-phase AC voltage startup signal to the plurality of windings resulting in a substantially sinusoidal current; altering the frequency of the three-phase AC voltage startup signal according to a frequency ramp function defined by the frequency values, wherein the three-phase AC voltage startup signal provides an open loop ramp up of the electrical machine; discontinuing the three-phase AC voltage startup signal when the frequency ramp function has completed; switching to a back electromotive force (BEMF) control mode, when discontinuing the three-phase AC voltage startup signal, by using a known estimated position of the rotor based on the frequency ramp function.