Method and system for evaluating reliability of power transmission line under combination of wind and ice

The invention provides a power transmission line reliability evaluation method and system under wind-ice combination, and relates to the technical field of power transmission line disaster evaluation. Comprising the following steps: determining an icing dangerous month of each period based on a monthly average temperature; fitting a probability density distribution function of a monthly average wind speed corresponding to an icing danger month, and calculating a wind-ice combined wind speed in a given return period; according to the extreme icing thickness of the set return period and the obtained wind-ice combined wind speed, calculating a wind-ice load acting on the power transmission tower line system; acting the wind-ice load on a pre-established power transmission line finite element model, and fitting to obtain a failure probability curve; and combining the failure probability curve and the probability density distribution function of the monthly average wind speed to obtain the total failure probabilit