Research On Protection Of Distributed Network Containing Distributed Generation

The problem of distributed network protection and feeder automation brought by Distributed Generation(DG) integrating into distributed network, grid characteristics of inverter-based distributed generation and output characteristics of inverter when the distributed network has fault is analyzed, then an equivalent model for fault analysis of distributed network with DG is proposed. Taking a widely used inverter for example, according to the known parameters, by calculation and get the equivalent output impedance of the inverter. Then considering the protection value and time limit of the inverter, eventually these parameters will be included in the established model.The short-circuit fault characteristic quantity of distributed network with DG is analyzed, sum up the different influences on protection of DG integrating different locations. And the location and capacity of protection of distributed network with DG, namely considering the protection as well as the active power loss of distributed network, using the improved particle swarm algorithm, planning distributed network with DG and the location and capacity of DG is determined.On the basis of existing research results, the fault calculation of distributed network with DG is carried out. According to the proposed algorithm for locating and sizing of DG, and get the distributed network with DG for fault calculations; equivalent impedance of the inverter and its control strategy are the important condition for the establishment of equivalent model, control strategies and fault output characteristics of the inverter will be the main constraint in the process of fault calculation. By programming calculation, each node and branch in the distributed network with DG, the amount of electrical slip case under different faults.This article does not want to change the original protection and automatic reclosing configuration greatly, by adjusting the protection value and time limit, and the protection of distributed network with DG to act reliably and sensitively. The results calculated by distributed network fault with DG is analyzed, compared with the distributed network without DG, sum up the protection scheme of distributed network with inverter-based DG. Finally, the protection configuration methods and procedures are proposed when the inverter-based DG is "T" connected to 10 kV distributed network.