Dynamic striking distance and electrical geometrical model of wind turbine blades based on lightning physics

One of the most key factors affecting the safe and reliable operation of a wind farm is the damage of wind turbine blades suffered lightning strikes. In this study, the electric geometrical model of wind turbine blade (EGMWB) was presented based on the combination of the electrical geometry method and the physical process of the lightning leader. The simulation of the development process of a lightning leader is based on the introduction of the concept and analysis method of dynamic striking distance. Moreover, the method of calculating the efficiency of blade lightning protection system (LPS) was deduced. The influence of blade angle, lightning current amplitude and the arrangement of the lightning arrester on the blade LPS efficiency is analysed based on the EGMWB. Analysis indicates that the efficiency of blade LPS reduces with the decrease of lightning current and the angle between the blade and horizontal, and the efficiency of blade LPS can be improved by increasing the side lightning receptors. The EGMWB provides a theoretical basis for lightning protection design and evaluation of wind turbine blades.