Study and discussion on the problems of Shaft Voltage and Bearing Current in Wind Power Generation System

In the modern wind power generation system, because of the large number of the high frequency power electronic devices, it brings the bearing current problems to the entire system, affecting the safe operation of the system and the life of generator bearing and other mechanical parts seriously. Precise analysis of distributed capacitance parameter is very important to predict shaft voltage and bearing current accurately. The chapter analyses common mode model of whole wind power generation system firstly. With study of the inner structure of the Wind turbines, the analytic calculation formula of distributed capacitances in the Wind turbines is put forward. Finite element method is also recommended. Based on the above analysis, formation mechanism and influence on bearing current of wind power generation system is determined.