Frequency converter for operating an electric motor, mechatronic system and electric device

摘要

The changer (4) has a rectifier (6), and an inverter (12) with steered half bridges (14u-14w) for switching of current supply on and off for windings (16u-16w) of a single-phase or polyphase electric motor (3). A control device (11) controls the half bridges, and a device for determining the current in a supply line (5) to the frequency changer. A determining device determines sum current based on single detected phase currents (Iu, Iv, Iw) by the control device. A damping element (17) comprises a reactor or a coil switched in the supply line. An independent claim is also included for an electric device.