Assessment of voltage SAG in distribution system regarding the uncertainty of wind-based distributed generation

This paper presents a new assessment of voltage sag due to faults in distribution system connected with wind-based distributed generation (WDG) in which some uncertain factors to this energy resource technology are considered. Voltage sag characteristics depend on the system´s short-circuit power (SSCP) that also includes the power injected from WDG when faults occur. The output power produced by WDG is a function of the wind speed that is stochastic in nature. By using the probabilistic modeling of wind speed at the WDG´s site, the uncertainty of wind regime is built into the problem of stochastic prediction of voltage sag in distribution system with wind energy resources connected. The paper assesses voltage sag performance in IEEE 34 Nodes Test Feeder. Voltage sag characteristics are determined in relation to wind speed for different scenarios of WDG sizing and placement, types of wind power generator and the impact of the system source capacity of the distribution system of interest.