A fuzzy comprehensive evaluation for metropolitan power grid risk assessment

The emerging global energy internet will connect major metropolitan cities together in the world. The power grid risk assessment of these big cities is very important and essential in securing the electrical energy system. In this paper, we propose a fuzzy comprehensive evaluation methodology to quantitatively assess the risks of a metropolitan city power grid system. A 2-level index and weight of importance have been established based on fuzzy comprehensive evaluation to assess the grid risks. An on-site working risk of exposure is quantitatively measured to evaluate the level of a single accident risk. The power grid of a western metropolitan city in China has been evaluated by the method above by using the accident records in past 5 years. The most significant secondary indices have been determined and the whole city power grid risk has been assessed. According to assessment result, some improvements have been taken to address these significant secondary indices, which will substantially improve the safety of the metropolitan power grid.