A Method to Evaluate Flexibility of Distribution Network Considering Grid-Connection of Electric Vehicles

Huge amount grid-connection of electric vehicles (abbr. EV) brings new challenges to the operation, dispatching, planning and development of distribution network. Under this background, a method to evaluated flexibility of distribution network, in which the grid-connection of EV was considered, was proposed. Firstly, based on the data of EV charging station in Hangzhou city and by use of kernel density estimation method an EV load model was established. Secondly, according to the element of power grid flexibility the definition of distribution network flexibility was given. Thirdly, overall considering multi scenarios and multi time-scale flexibility indices, a distribution network flexible evaluation method based on information entropy and DS evidence theory was proposed. Finally, the flexibilities of distribution network under multi scenarios were contrasted, thus the effectiveness of the proposed model is verified. The proposed model is available for reference to draw up one of the guiding standards for distribution network planning under the scenario of grid-connection of huge amount EV in the future.