Principle and characteristics of a new type AC servo motor 'VARIFIELD'

The authors previously proposed a novel brushless synchronous motor, the half-wave rectified brushless synchronous motor (1989). Kyowa Kiden Co., Ltd. started production of a new type AC servomotor series named 'VARIFIELD', which is based upon this machine theory. This motor has simple and robust brushless structure and is maintenance free. It provides torque control operation over a wide speed range, from zero to the rated speed. In this paper, the authors describe the principle and present overall test results, such as steady-state characteristics and step response.<>