High-field self-starting permanent-magnet synchronous motor

A number of configurations of self-starting permanent-magnet synchronous motor have been developed in recent years. This paper describes a form of motor having a high efficiency/power-factor product. Use can be made of ferrite, Alnico or rare-earth magnets. The machine is particularly suitable for variable-speed drives involving the combination of an inverter and one or more synchronous motors, where the speed of rotation needs to be accurately determed. The characteristics of the machine are discussed results indicating the performance are presented.