A METHOD AND AN APPARATUS FOR FILTERING AN ELECTRIC CURRENT SUPPLIED TO A MOTOR

摘要

The present invention relates to a method and an apparatus for filtering an electric current supplied to a motor (M). A current supplied from a frequency transformer means (4) provided with a voltage source circui t to the motor (M) is conducted through a coil means (L) between the frequency transformer means (4) and the motor (M) for preventing any essential rapid increases of the current. The reactive current portion of the motor (M) is compensated by a condenser means (C) arranged between the frequency transformer means (4) provided with the voltage source circuit and the motor (M). By means of the inventive filter the reactive current of the motor (M) is essentially compensated and the power ratio thereof is increased.