Design of a self-starting hybrid permanent magnet hysteresis synchronous motor connected directly to the grid

Abstract

In this work, a permanent magnet hysteresis synchronous (PMHS) motor was designed to improve the efficiency of the system. The proposed motor is intended for pumping applications, such as submersible pump motors, fire pumps, oil-well pumps, and circulation pumps requiring high-speed operation. The efficiency of the pump system increases depending on the speed of the pump fans. The total efficiency of the pump system is reduced because the load increases exponentially in these types of application systems. The speed is important for the pumping applications in order to improve the efficiency of the pump system. Nowadays, traditional induction motors are widely used in these applications; however, they experience rotor slip when operating under synchronous speed with loaded conditions. The system efficiency is dramatically reduced when the rotor slip is increased by depending on the pump load. The proposed motor can achieve self-starting without any kind of driver for direct connection to the grid. In addition, the proposed motor can be operated at synchronous speed under full load conditions. The designed motor is analyzed by using simulation results, such as the performance of the starting motor at various loads, stator-rotor flux density, and synchronous speed at stand-still.