Analysis on the Characteristic of the Instantaneous Inrush Current of Brushless Doubly Fed Induction Generator

Abstract

Compared with traditional doubly-fed induction generator (DFIG), the brushless doubly-fed induction generator (BDFIG) eliminates the slip rings and brush gear, which benefits high reliability and low maintenance costs. Thus BDFIG promises broad application prospects in power generation. With the rapid growth capacity of the power generation system, the inrush transient current becomes an important factor that cannot be ignored. The paper analyzes the characteristic of the inrush current of BDFIG under synchronization error. First, the character of the inrush current is analyzed under the s-domain, which can be understood more clearly; Second, in order to analyze character of the inrush current under time-domain, the specific expression of inrush current is obtained with amplitude error and phase error. Third, the influence of amplitude error or phase error is also investigated based on the obtained expressions. Finally, the analysis is verified by both the simulation and experimental results. The work could facilitate future research on suppressed the inrush current of BDFIG, thereby increasing the security and stability of the system