Ac/Dc Hybrid Power Distribution Network Power Flow Calculation

With the development of the distributed energy and user load,dc power distribution technology with its huge economic and technical advantages walk into people's horizons.Apply DC technology based on voltage source converter to the traditional urban AC distribution network,and construct a new type of AC-DC hybrid urban distribution network,which can effectively alleviate the problems faced by the urban distribution network and promote the development of the urban distribution network to efficient and environmentally friendly smart grid development.Power flow calculation is the basis for power system planning,design,and operation control.The AC-DC hybrid distribution network changes its operation mode due to the access of distributed energy and DC loads.In the power flow calculation of AC-DC hybrid distribution network,it is necessary to combine the power flow calculation method of AC-DC hybrid transmission system and the traditional AC distribution network power flow calculation method.In the power flow calculation,the particularity of AC-DC hybrid distribution network needs to be considered.this paper studies ac/dc hybrid power distribution network,improve on these two methods,and make it better for ac/dc hybrid trend analysis of the distribution network.Firstly,the article analyzes the application prospects of the city's AC/DC hybrid distribution network.By analyzing the topology of the DC distribution network,a future city AC/DC hybrid distribution network based on medium voltage DC distribution network is proposed.Second,the ac/dc hybrid power flow calculation model is set up in this chapter,including component of ac system model and component model of dc system,building steady state model of voltage source inverter and analyzing the control method.Finally,this paper analyzes the distribution network power flow calculation methods,the application of two commonly used in ac/dc power flow calculation algorithm was improved,the unity of the newton-raphsoniterative method based on expanding node calculation method,the alternate iteration method consider the asymmetry of three-phase distribution network,using the improved three-phase forward sweep method to calculate the trend of the communication network.Through the construction example,using MATLAB software to programming calculation,respectively,with three converter station and one ac/dc hybrid power with 30 three-terminal dc network node and including 2 converter station and 1 dc network ac/dc hybrid power distribution network with 33 nodes.the proposed algorithm is verified,and the simulation results verify the validity and effectiveness of the proposed algorithm.