A Four-terminal Soft Open Point Planning Method for Active Distribution Network Considering Reliability Benefits

In view of the lack of discussion on the connection mode of double-loop network and the measurement of reliability benefit in the current soft switch (SOP) planning method, this paper proposes a four-terminal SOP planning method for active distribution network considering the reliability benefits. Firstly, the application scenario of four-terminal SOP and its control mode under normal and fault operation of distribution network are discussed. Secondly, the four-terminal SOP two-layer planning process of active distribution network is proposed, which includes planning and operation. On this basis, a planning model aiming at minimizing the sum of annual investment and operation and maintenance cost of four-terminal SOP, normal operation cost and reliability cost of distribution network is constructed. Thirdly, the mixed integer nonlinear programming model is solved by combining particle swarm optimization, cone programming and monte carlo simulation.