전압 제한타원 중심점에 따른 계자 권선형 동기 전동기의 특성 분석

Abstract

Studies on eco-friendly vehicles such as Hybrid Electric Vehicle (HEV) and Electric Vehicle (EV) which are to be used as alternative means of transportation in the near future due to the depleting pool of natural resources and pollution issues which came hand in hand with the recent dramatic increase of fossil fuels use are conducted at national and corporate level. Of the traction motors for eco-friendly vehicles, Permanent Magnet Motors using rare earth metal have been mainly used until now. However, due to the soaring price of the rare earth elements, the development of nonrare earth motor has been highly demanded. Of these non-rare earth motors, studies on WFSM (Wound Field Synchronous Motor) are actively conducted recently in terms that high power density and controllable power factor and various control variables. In the meantime, WFSM (Wound Field Synchronous Machine) has been mainly used for large generators and rarely used for motors and thus, papers or technical references on their use for motors are relatively hard to find. This thesis analyzes the characteristics of the WFSM. WFSM is designed by changing the rotor shape of a 150kW class IPMSM designed for vehicles into a wound field type and the basic characteristics and power characteristics at rated speed are compared as well as analyzed. Moreover, the control characteristics variation of the WFSM corresponding to the varying rotor shape in IPMSM via current map are checked and power characteristics at maximum speed are compared and analyzed. To verify the control characteristics corresponding to these various models of WFSM, the relative position of the central point of current limit circle and voltage limit ellipse is defined as M value and 3 models according to M value are designed through inductance change. Through the model designed according to unique Mmax value of motor, the current control method of maximum power on complicated 3 variables control is presented.