Patent ID: 9281768
Filing Date: 2016-03-08
CPC Classification: H02P

Claim Text:
1. A method for synchronizing a rotation speed of a permanently excited rotor of an electric motor with a frequency of a rotation field of a sensorless commutated stator of the electric motor during a run-up or start-up procedure of the electric motor, comprising: determining a phase position of the rotation field and a phase position of a countervoltage that is induced by the rotor in the stator in order to obtain a phase offset between the rotation field and the countervoltage; and adjusting a prevailing amplitude at least of one component of the rotation field using the phase offset in order to synchronize the rotation speed with the frequency, wherein the amplitude of the component is increased if the rotor is lagging behind the rotation field or the amplitude of the component is reduced if the rotor is running ahead of the rotation field.