Method and device for determining lightning conductor protection angle of insulating overhead line

The invention provides a method and device for determining the lightning conductor protection angle of an insulating overhead line. The method includes: using the empirical formula of the line to determine the expression of the lightning trip-out rate, in regard to the lightning conductor protection angle, of the line; acquiring the constraint conditions of lightning conductor parameters associated with the lightning conductor protection angle; using the expression to calculate the lightning trip-out rate, and under the condition that the constraint conditions are satisfied, selecting the protection angle corresponding to the minimum lightning trip-out rate as the final determined lightning conductor protection angle. The method has the advantages that the relational expression between the lightning trip-out rate and the lightning conductor protection angle is determined by using the empirical formula, the lightning conductor protection angle is selected under the conditions that the lightning trip-out rate i