Abstract
Permanent magnet synchronous motor (PM motor) is widely used for several industrial applications. Some applications such as an electric vehicle and a compressor drive require a constant power operation. The operating limits and the constant power speed range deeply depend on the machine parameters. The relationships between the motor parameters and the operating performance have been theoretically examined. This paper examines the performances of the prototype synchronous motors, where a stator structure and a rotor structure of all motors are the same. The permanent magnets are inserted into the rotor slits and the volume of permanent magnet is adjusted to control the magnet-flux linkage. The effects of adding magnet into the rotor on the machine parameters and the operating performance are examined based on the various experimental results. The prototype motor has flexibility on the speed versus power performance by adjusting the volume of permanent magnet. The theoretical results with respect to the operating limits and the motor parameters are also confirmed experimentally.
