Method And Device For Determining Pole Wheel Position Of Electronically Commutated Electrical Machine

A method is disclosed for determining a pole wheel position of an electrically excited electrical machine. The method comprises the steps of injecting voltage test signals at a plurality of space vector angles with a fundamental frequency which lies in a frequency range in which there is a difference in admittance in especially 90-degree space vector angles; calculating resulting values of an excitation current indicator variable as Fourier coefficients of the excitation current resulting from the voltage test signal with reference to the fundamental frequency of the voltage test signal at the corresponding space vector angles; determining the pole wheel position on the basis of the profile of the excitation current indicator variable; calculating resulting values of a stator current indicator variable as Fourier coefficients of a stator current resulting from the voltage test signal with reference to the fundamental frequency of the voltage test signal at the corresponding space vector angles; and determining the pole wheel position on the basis of the profile of the stator current indicator variable.