A Flexible Planning Model of Transmission Network Under Interval Load

Considering load uncertainty in power network expansion planning,taking minimum cost investment as objective function and the security of transmission network under both normal and N–1 conditions as constraints,an flexible planning model for transmission network under interval load is built,a transmission network flexible planning under interval load,which can meet the requirement of system security under both normal and N–1 conditions,is achieved by solving the proposed model.During the solving process,the upper limit of interval numbers of minimum load shedding are calculated to judge both security and security degree of transmission network planning scheme under interval load,and utilizing improved greedy randomized adaptive search procedure algorithm(GRASP) the solution of the proposed model is speeded up.The correctness and effectiveness of the proposed model are verified by planning results of a 6-bus system and a practical 77-bus system.