Abstract: A method for identifying magnetic anisotropy of an electric three-phase machine having a rotor and a stator is provided. The method includes actuating the machine with a periodic injection voltage via clocked clamping voltages according to a pulse width modulation (PWM) scheme having a switching frequency. An electric current of the machine responsive to the machine being actuated by the periodic injection voltage is cyclically measured at a sampling frequency. The periodic injection voltage has a period that is less than twice a period of the sampling frequency. An inductance and/or an admittance of the machine is determined based on the periodic injection voltage and the measured electric current. A position of the rotor is determined based on the inductance and/or the admittance of the machine. The machine is controlled according to the rotor position.

Abstract: A method is for use with a synchronous machine having a stator and a rotor with or without permanent magnets. In operation, electric current of the synchronous machine responsive to the synchronous machine being actuated via clocked terminal voltages is measured. A magnetic flux linkage is determined based on the clocked terminal voltages and the measured electric current. A profile of the magnetic flux linkage as a function of rotation of the rotor, under a boundary condition of an at least two-dimensional electric current vector that is unchanged in coordinates of the stator, is used to detect a position of the rotor. The synchronous machine is controlled according to the rotor position.

Abstract: A method and a device provide load-free determination of load-dependent position assignment parameters of a synchronous machine without using a position sensor. The synchronous machine is controlled via clocked (pulsed) terminal voltages from which, in conjunction with the measured electric current response, the inductance or admittance is calculated or wherein the load-free lowest and the load-free highest differential inductance are known. Based on the load-free lowest and the load-free highest differential inductance and the short-circuit electric current, the magnetic saturation behavior of the absolute inductance and/or of the magnetic anisotropy of the synchronous machine under load is predicted and used in the position sensor-free control operation (i.e., closed-loop control mode without a position sensor) for position assignment.

Abstract: A method and a device for assigning the inductance or admittance to the rotor position of a synchronous machine having a stator and a rotor with or without permanent magnets. In operation, the synchronous machine is activated by way of timed terminal voltages and the inductance or admittance is calculated from the terminal voltages and the measured current response. In this case, the variation of the inductance or admittance over the rotor rotation under the boundary condition of an at least two-dimensional current vector that is unchanged in stator coordinates, is used as key information for the positional assignment.

Abstract: A method is for use with a synchronous machine having a stator and a rotor with or without permanent magnets. In operation, electric current of the synchronous machine responsive to the synchronous machine being actuated via clocked terminal voltages is measured. A magnetic flux linkage is determined based on the clocked terminal voltages and the measured electric current. A profile of the magnetic flux linkage as a function of rotation of the rotor, under a boundary condition of an at least two-dimensional electric current vector that is unchanged in coordinates of the stator, is used to detect a position of the rotor. The synchronous machine is controlled according to the rotor position.

Abstract: A method and a device provide load-free determination of load-dependent position assignment parameters of a synchronous machine without using a position sensor. The synchronous machine is controlled via clocked (pulsed) terminal voltages from which, in conjunction with the measured electric current response, the inductance or admittance is calculated or wherein the load-free lowest and the load-free highest differential inductance are known. Based on the load-free lowest and the load-free highest differential inductance and the short-circuit electric current, the magnetic saturation behavior of the absolute inductance and/or of the magnetic anisotropy of the synchronous machine under load is predicted and used in the position sensor-free control operation (i.e., closed-loop control mode without a position sensor) for position assignment.

Abstract: A method and a device for assigning the inductance or admittance to the rotor position of a synchronous machine having a stator and a rotor with or without permanent magnets. In operation, the synchronous machine is activated by way of timed terminal voltages and the inductance or admittance is calculated from the terminal voltages and the measured current response. In this case, the variation of the inductance or admittance over the rotor rotation under the boundary condition of an at least two-dimensional current vector that is unchanged in stator coordinates, is used as key information for the positional assignment.