Propagation of Voltage Dips in a Mixed DFIG-PMSG Wind Power Plant

Abstract

This work assesses the propagation of voltage dips caused by electrical faults in a mixed DFIG-PMSG wind power plant by considering distinct collection transformer connections. Several transmission system operators have required the operation of the wind power plants even during voltage dips. The electronic converters might be affected during the voltage dips. Most of the works which assess this impact applied voltage dips directly to wind turbine terminals. However, the voltage dips which reach the wind turbine terminals are distinct in type of the ones from the transmission level. The reason for this distinction is related to the winding connections of the wind turbines and collection grid transformers. The winding connection of the collection grid varies country by country, i.e some countries apply Yg- Yg and other Yg - A. Faced with this, the consideration of the winding connections might possibly lead to distinct operation of the wind turbines during the voltage dip. Besides, the operation during dips also differs depending on the converter technology. This way, this works aims to analyze how the low-voltage ride-through requirements and the behavior of the wind turbines changes in terms of the collection grid transformer for two technologies of wind turbines: PMSG and DFIG.