Patent ID: 9212894
Filing Date: 2015-12-15
Classification: G01B,H02P

Abstract:
1. An apparatus for determining a position of a rotor of an electrical machine in relation to a stator, comprising: at least three phase strands arranged in the electrical machine which each include at least one pole winding with a magnetizable core; a current supply circuit that includes switching devices by which a positive or a negative pole of an operating voltage source is selectively applicable to the phase strands via connecting conductors, and further switching devices by which at least one of the phase strands is selectively isolatable from the operating voltage source; and devices for determining a measurement signal which is determined by current degrees of magnetization of the pole winding cores which depend on the position of the rotor, wherein the measurement signal is a DC voltage of the operating source, which DC voltage is divided in accordance with momentary inductivities of at least two of the phase strands, wherein the devices for determining the measurement signals are provided to pick up the measurement signals exclusively outside of the electrical machine at the connecting conductors serving for supplying current to the electrical machine, wherein the further switching devices are provided for temporarily separating at least one of the connecting conductors from the operating voltage source, and the measurement signal can be picked up at the connecting conductor separated from the operating voltage source.