Study On Locating And Sizing Of Soft Open Points In Distribution Network

At present,there are some problems in distribution network in China,such as lagging construction,unreasonable structure and limited control measures,restricting the flexibility of operation control of distribution network,resulting in low voltage of distribution network and long recovery time after fault.On the other hand,with the improvement of new energy penetration in distribution network,higher requirements are put forward for power quality and reliability.In summary,the distribution network is facing many challenges,such as low terminal voltage,abandoning wind and light,insufficient power supply support for important loads,and so on.These problems can not be effectively solved simultaneously by conventional control methods.Soft Open Points(SOP)adopts a new power electronic technology,which can continuously regulate power.It also has flexible control mode,avoiding power supply interruption and closing impulse caused by conventional switches.It can also improve the terminal voltage level of distribution network and promote the balance of feeder load distribution.It provides key technology and equipment support for the implementation of intelligent distribution network.The main contents of this paper are as follows:Firstly,this paper deduces the commutation principle of two-port SOP and multi-port SOP,then analyses the common control strategies of SOP,the working mode and corresponding uses of SOP.Secondly,aiming at the location problem of SOP in distribution network,this paper proposes a dynamic coding scheme for multi-port SOP in interconnected distribution network and a location strategy for minimizing the voltage deviation,which make the SOP location problem,a complex mixed integer non-linear programming problem,be solved quickly and accurately.The simulation result shows that the best SOP location scheme can be selected to optimize the network structure,enhance the voltage regulation ability and overload protection ability of distribution system.Finally,a benefit evaluation model of distribution network is established to solve the sizing problem of SOP considering both economy and power supply reliability.By simplifying SOP working mode and using and union-find algorithm,the solving speed of sizing problem is greatly improved.The simulation result proves the superiority of the proposed algorithm in solving speed.It is also proved that the proposed scheme can improve economic benefits,promote intermittent energy consumption,and ensure the reliability of distribution network power supply.