Wind Forecast-Based Probabilistic Early Warning Method of Wind Swing Discharge for OHTLs

Abstract

Strong winds, ice storms, lightning, and other extreme weather events predominantly affect the security of overhead transmission lines (OHTLs). Thus, it is important to use the weather forecast information to predict the possible fault events and make an early warning to improve the operational reliability of the power system. Wind swing discharge is a common failure mode under strong winds or downbursts. Wind swing discharge early warning can be treated as a typical problem of comparison and prediction with uncertain inputs as a consequence of fluctuations. This paper proposes a probabilistic early warning method of wind swing discharge based on wind forecast. First, the influences of wind forecast accuracy on the prediction of the swing angle are analyzed. Then, the probability distributions of forecast wind direction angle and wind speed are established based on the prior distribution of wind forecast accuracy. The wind swing angle is calculated based on wind direction and wind speed samples through Monte Carlo simulation. The calculated swing angle is then compared with the designed maximum swing angle of the suspension insulator string to realize the probabilistic early warning of wind swing discharge for OHTLs under short-range wind forecasts. Finally, the proposed method is verified with a practical example.