Abstract：Taking pressure loss of 220kV for some city as example, based on event tree, the paper analyzed the power accident, and the results of analysis and protection measures was visually displayed by using the Bowtie visual function. The results showed that, inadequate quality of equipment, daily operation and, maintenance, and lack of power grid operation management were threats; value of lost load, important user power outage and equipment damage and loss were the consequences. Combining the existing research results and the reality of power grid management, based on the grid design planning, risk identification, safety inspection etc., the Bow-tie visualization analysis diagram with blackouts as the top event was established, which displays visually weak links of safety management and safety protection measures, and provides the basis for safety management of power grid.
2015, Vol. 16 
