A Novel High-Efficiency Parallel-Winding Connection for a Three-Phase Induction Motor Fed by a Single-Phase Power Supply

A novel high-efficiency parallel-winding connection for a three-phase induction motor fed by a single-phase power supply is presented in this paper. The proposed connection uses two sets of capacitors to achieve approximately symmetrical winding currents in the motor. A 2-D finite-element magnetodynamic model of the induction motor is presented. The Kriging surrogate model along with a global optimization method was used to find the optimal operating conditions of the proposed motor. Based on the conditions for the best efficiency at full load and the best starting torque of the motor, a straightforward calculation is proposed to select the capacitors. To demonstrate the validity of the proposed connection, experimental tests are performed in three induction motors. It is demonstrated that the rated load efficiency is the same and the starting torque is close when the motor is fed by a single-phase and three-phase power supply. Additionally, the rated power factor of the motor is near to unity. Our proposed motor connection has higher efficiency and higher power factor than a conventional single-phase motor.