Enhanced Efficiency of Direct-Drive Switched Reluctance Motor With Reconfigurable Winding Topology

Direct-drive motors (DDM) serve a vital role in reducing assemble complexity of mechatronics system and improve operation efficiency. However, design of DDM for washing machine is difficult, DDM needs to generate high torque at ultra-low-speed during rinse and reach high speed during dehydration, while keeping high efficiency. This paper puts forward a direct-drive switched reluctance motor (DDSRM) with reconfigurable drive topology for washing machine, the connections between pole windings in one phase of DDSRM can be reconfigured according to rotational speed. Three winding topologies are proposed in this paper, which leads to different speed range, efficiency and winding current. Topology switching mechanism are given, efficiency of DDSRM under different topologies are compared to find optimal speed to switch topology. A fast power loss calculation model is built to analyze the influence of turn-on and turn-off angles on DDSRM efficiency under different topologies, an online switching angles optimization method that matches topology switching strategy is proposed. A 24/16 3-phase out-rotor DDSRM was used in experiment to verify the effectiveness of topology switching strategy and switching angels optimization method, the results showed that the speed range of DDSRM is extended, efficiency of DDSRM over wild speed range can be significantly improved. The DDSRM with reconfigurable winding topology is of great value in promoting direct-drive technology for house-hold appliances, hydraulic system and aerospace actuators.