Patent ID: 7944158
Filing Date: 2011-05-17
Classification: H02P,Y10T

Abstract:
1. Field-oriented control method for an electric drive comprising a plurality of electric motors, for implementing a tension mechanism, for load cable and/or gearing means ( 1 , 3 ), using measurements of a polyphase motor actual current (U, V, W), the measured values of which are transformed into a direct current component and a quadrature current component, based upon a magnetic rotor field or flux angle, in a rotor flux-based d,q coordinate system, and the quadrature and direct current components from the actual current are subjected to a comparison with predetermined quadrature and direct current components (isq_ref, isd_ref) of a current command value, with the following steps: a) two synchronous motors (M b) the magnet wheels or rotors of the two synchronous motors (M c) the two synchronous motors are each supplied with or traversed by the same phase currents, from a shared power converter d) for a pretension torque, a command or reference value is predetermined, and is superposed on a motor torque control value (m_ref) output by a controller ( e) a direct current component (isd_ref) for the current command value is derived from the predetermined tension torque control value (m_ref) with sign reversal.