Virtual Dodecagonal Voltage Space Vector Structure based Control Scheme for Suppression of Low Order Harmonics in Induction Motor Drives

This paper presents a virtual dodecagonal voltage space vector-based control scheme for induction motor drives. The scheme helps in significant suppression of low order harmonics like fifth and seventh order harmonics. The suppression of these harmonics helps in producing a much better voltage profile compared to the six-step operation of a conventional hexagonal voltage space vector structure (VSVS) based switching scheme. The reduction in the magnitude of low order harmonics significantly reduces torque pulsations. The vectors in the proposed dodecagonal voltage space vector structure are virtual voltage space vectors which are generated in an average sense by switching the actual voltage vectors of a hexagonal voltage space vector based structure. This virtual dodecagonal voltage space vector based structure can be realized using a single 2-level voltage source inverter. The proposed scheme is validated by extensive simulation using MATLAB/Simulink software and experimentally verified on a laboratory prototype using TMS320F28069M digital signal controller.