With the extensive access to high penetration of renewable energy sources and large-scale flexible load

in a market environment

the electric power production or consumption of consumers to maximize their own interests may lead to excessive concentration of power flow in time and space

resulting in the congestion problem in active distribution networks(ADNs). A congestion management method of ADN is proposed based on the soft open point(SOP)and market mechanism. Faced with the response characteristics of flexible load with locational marginal price

a congestion management model based on SOP and electricity price mechanism is proposed to solve the congestion problem by integrating the direct control methods with market methods. Case studies on the PG&E 69-node system are made to verify the effectiveness of the proposed congestion management method. It is shown that the method can effectively solve the congestion problem and SOP has appreciable effects in alleviating system congestion and reducing the congestion cost.