A Critical Look at Control for Maximizing Wind Resources in PMSG Turbines

Abstract

It is common to find reports of disconnections of wind turbine units in wind farms when external short circuits occur, these faults are perceived by the wind turbine units as voltage dips and their disconnection is very fast. This work analyzes the operation of variable speed synchronous wind turbines connected to the grid, and the problems that these systems present in the face of disturbances, such as voltage dips. The use of a computational tool was used to evaluate the behavior of the control system in the face of disturbances caused by voltage dips. The events that generate the disconnection of the generation units, instead of mitigating the effects, were studied. It was determined that the control system confuses the voltage reduction with lack of wind and sends orders to maximize the wind resource, and then the momentary action of the braking units in the presence of a voltage dip is originated. It was concluded that the control system tolerates voltage dips depending on their depth and duration, the highest value being 50% of depth (voltage) and ranges less than 300 milliseconds of duration