Power Flow Calculation And Its Application For Distribution Grids With Distributed Generations

With the implement of smart grid, the application of distributed power in distribution network will be more and more widely. Distributed generation has the advantages of low cost, low lost, high reliability, and diversity of energy resources. But the interconnection of distributed generation to power grid can make large influence, such as reverse power flow, loop network and new node types that are difficult for the traditional power flow method to deal with. So the power flow methods used in traditional distribution system will not meet the requirement of distributed generation systems. In order to solve this problem, this paper carries out research on the power flow algorithm for the distributed generation system. This paper investigated the behavior and modeling of the typical DG. The power flow approach based on the Impedance Iteration and PV node Correction (IIPVC) was described, which was compared with the forward and backward power flow calculation and the Newton approach, showing the good performance of IIPVC.Put the suggestion flow calculation method into distribution network reconfiguration process, in order to make the distribution network more security, more reliable, more economic. The tradition network reconfiguration is static reconfiguration. But in the actual operation process of the distribution network, each node load were in constant change and under the limited times of switch operation, impossible to network reconstruction constantly, so the study of a period of time, the dynamic network reconfiguration problem more tally with the actual situation. This paper discusses a distributed power dynamic reconfiguration method. Using the Tabu search algorithm good global optimization ability. Applied the solution vector consists of the initial instants and the topologies of each period, the index was to minimize the loss energy in the whole day into dynamic network reconfiguration. The constraints may include the maximum switching times. The best operation modes and their corresponding switching instants can be determined by the proposed algorithm simultaneously. A 19-node distribution grid with DG was used as the example, the results of which show that the proposed method is effective and feasible.