Output sinus filter for medium voltage drive with direct torque control

For improving the motor voltage quality and for eliminating the high dv/dt associated problems like electromagnetic interference (EMI), additional motor losses, need of high-insulation class motors and overvoltages at motor terminals when long cables are used, this paper presents the design of an output sinus filter for medium voltage drive and the implementation of resonance compensator for active damping of the resonance frequency of the system filter-motor without losses. The paper also includes the analysis of the dynamic model of filter-motor required in the DTC control routine, the implementation of neutral point control and switching frequency control.