풍력발전시스템용 회전자 계통연계형 이중여자 권선형 유도발전기의 설계

Abstract

Doubly-Fed Induction Generators (DFIGs) are widely used for modern wind turbines. The stator winding of the conventional DFIG is directly connected to the grid while a rotor winding is connected to back-to-back AC/DC/AC converters. This paper proposes a grid-connected to a rotor type DFIG that rotor winding is connected to the grid instead of stator winding. Although the conventional grid-connected to the stator type DFIG cannot utilize core around rotating shaft as flux path, the proposed type can use rotor core efficiently. In addition, the stator size of the proposed type can be reduced because the current of the stator winding is decreased. In order to verify the size reduction of the proposed type, a loading distribution method (LDM) is utilized. As a result, the stator outer diameter of the proposed type was decreased by about 3.9 %.