Single phase line-start high efficiency interior permanent magnet motors

Over the past 25 years, line-start fractional horsepower interior permanent magnet synchronous motors have expanded their presence in the domestic marketplace from few specialized niche markets in high efficiency machine tools, household appliances, small utility motors and servo drives to mass-produced applications. A closer examination reveals that several different knowledge-based technological advancements and market forces as well as consumer demand for high efficiency requirements have combined to accelerate the development of the improved new small energy efficient motors. The purpose of this paper is to provide a broad explanation of the various factors that lead to the current state-of-the-art of the single phase interior permanent motor drive technology. A unified analysis of single phase interior permanent magnet motor that permits the determination of the steady state, dynamic and transient performances under different operating conditions is presented. The mathematical model is based on both d-q axis theory and finite element analysis. It leads to more accurate numerical results and meets the engineering requirements more satisfactorily than any other methods. Finally, some concluding comments and remarks are provided for manufacturing and future research trends of line-start energy efficient permanent magnet synchronous motors.