In order to improve the effectiveness and scientificalness of risk assessment of lightning trip-out for power grid and realize the differentiated lightning protection technology

a new method of risk assessment of transmission line lightning trip-out is proposed based on the theory of natural disaster. As hazard-pregnant environment factors of lightning trip-out

the elevation

slope

aspect

land use type and river network density are selected to establish a assessment model of hazard-pregnant environment factors of lightning trip-out. The assessment indices of disaster-causing factors included the ground-lightning density and ground-lightning intensity observed by the lightning detection and location system. And the lightning protection level is selected as the assessment indices of vulnerability of disaster-bearing body. Based on the theory of natural disaster

the disastercausing factors

lightning protection level and hazard-pregnant environment are selected as assessment indices to establish the risk assessment model of lightning trip-out in Zhejiang Power Grid by AHP method. And the risk distribution of lightning trip-out in Zhejiang Power Gird for different return periods are given which could provide technical support for lightning protection level upgrading and reconstruction. The results show that the high risk distribution of lightning trip-out is mainly located in the North of Zhejiang

such as Huzhou

Jiaxing

Ningbo and Shaoxing

and Taizhou. The low risk distribution is mainly located in coastal areas and islands.