2019
Volume 19, Number 3/4, pp. 91-95
Iron loss evaluation for a small high-efficiency motor stator core made from an ultrathin electrical steel sheet under pulse width modulation inverter excitation using the stator winding excitation method
Mohachiro Oka,1 Masato Enokizono,2 Daisuke Wakabayashi3 and Hirofumi Kiyotake1
1 National Institute of Technology, Oita College, 1666 Maki Oita-city, Oita, 870-0152, Japan
2 Vector Magnetic Characteristic Technical Laboratory, 533 Joi Usa-city, Oita, 879-0442, Japan
3 Nippon Bunri University, 1727 Ichigi Oita-city, Oita, 870-0397, Japan
The motors for drones, robots and rovers rotate at high speed, and they are driven by a high-frequency power supply. To achieve high efficiency, they are often driven by a pulse width modulation (PWM) inverter. To reduce the eddy-current loss in such motors, we developed a new stator core made of 0.08 mm ultrathin electrical steel sheet. To evaluate the magnetic properties of a stator core with a complex shape, we developed a stator winding excitation method. We measured the magnetic properties of the new stator cores made of the ultrathin steel sheet and of 0.35 mm thick electrical steel sheet under PWM inverter excitation. The iron loss of the core made of the ultrathin sheet was much smaller than that of the core made from the 0.35 mm thick sheet.
Keywords: eddy-current loss, iron loss, PWM, stator core, ultrathin electrical steel sheet