In order to ensure system security when a number of transmission lines were on DC de-icing meanwhile and avoid heavy ice-coating on lines,a decision-making method of power system DC de-icing plan based on equal-risk was proposed.In this method,the equal expected load-shedding was the objective function,under the constraints and on the basis of the existing dc de-icing plan,lines’ de-icing time slots were determined by sequence.After DC de-icing time slot of a line was determined,the constraints of the rest lines need be updated and then DC de-icing decision-making of the next line was started.During each decision-making,the strongly restricted lines were arranged with first priority,then the selected line was arrange into the time slot with lowest expected load-shedding which was calculated according to Monte Carlo method. In addition,the urgency of DC de-icing was the constraint for the safety of the line.Finally,the example of Guizhou power grid verified the feasibility and effectiveness of the method.
