Study on Low-cost Soft-starting Method for Three-phase Asynchronous Motor Connected to Single-phase Supply

A new circuit topology based on thyristor control was proposed and discrete frequency control strategy was adopted,which realize soft starting of three-phase asynchronous motor connected to single-phase supply.Also,the soft-starters with single-phase supply and three-phase supply were compared.Both the simulation and experimental results indicate that this method can not only reduce starting current but also obtain enough starting torque.