METHOD FOR REDUCING COMMON-MODE INTERFERENCE CURRENTS IN AN ELECTRIC DRIVE SYSTEM, AND CORRESPONDING ELECTRIC DRIVE SYSTEM

摘要

The aim of the invention is to reduce common-mode interference currents in an electric drive system comprising at least two pulse converters (1, 2) that are powered by a common DC power supply device (4) and power an electric polyphase machine (3) comprising at least two winding phases (31, 32) or at least two winding systems (33, 34). Said aim is achieved by the fact that at least two pulse converters (1, 2) are respectively triggered by a control device (5) in such a way that the potentials (U1a, U1b, U1c or U2a, U2b, U2c) that are decisive for common mode currents (Icm1, Icm2) to be generated are applied in an at least approximately simultaneous manner to the winding phases (31, 32) affected by parasitic capacitances (Cp31, Cp32) or the winding systems (33, 34) of the polyphase machine, which are affected by parasitic capacitances (Cp33, Cp34), at the outputs (1a, 1b, 1c or 2a, 2b, 2c) of both pulse converters (1, 2) such that the voltage potentials (Uc31, Uc32 or Uc33, Uc34) are inverted relative to each other above the parasitic capacitances (Cp31, Cp32) of the winding phases (31, 32) or the parasitic capacitances (Cp33, Cp34) of the winding systems (33, 34) in relation to the potential to ground.