Apparatus for reducing dangerous bearing voltages

Abstract

An apparatus (1) for reducing bearing voltages in an electric machine (M) with a rotor (2) and a stator (3). A rotor-side and stator-side bearing outer ring (4r, 4s) and a respective bearing inner ring (4i) are provided between the rotor (2) and stator (3). A connection electronics system connect with the motor (M). A compensation arrangement (20) adjusts the potential (ULA-stator) of the bearing voltage at the bearing outer rings (4r, 4s) and the respectively corresponding bearing inner ring (4i) to an identical value. The compensation arrangement (20) comprises an impedance (ZKOMP), of at least one first impedance (ZKOMP, R) between the stator (3) and the rotor-side bearing outer ring (4r). The impedance (ZKOMP) has at least one impedance (ZKOMP. S) between the stator (3) and the stator-side bearing outer ring (4s).

Dependencies are inferred from the claim text.