Feasibility of Four-Switch Three-phase Brushless DC Motor Control Scheme Based on Quasi Z-Source Network

This paper proposes a novel four-switch three-phase brushless dc motor control scheme based on quasi Z-source network (QZFSTP), which improves the utility ratio of DC voltage, extends the range of speed and increases the output torque. The additionally partial circuits of quasi Z-source network and the bridge arm of four-switch inverter constitute the quasi Z-source converter. During the operation of motor, shoot-through states are inserted. Then the input voltage of inverter increases and the performance of motor can be markedly improved. The operating principle of four-switch three-phase (FSTP) brushless dc motor are analyzed, and the new topology and its controlling method are illustrated in detail. The experimental result indicated that the novel circuit structure could solve above problems effectively.