Influence of Distributed Generations on Transient Voltage Characteristics of Distribution Network

The accessing of distributed generation resources to distribution network causes the distribution changing of voltage for distribution network, and such problems as the voltage transient fluctuation and voltage quality arise when the failure occur in distribution network will arise. To solve these problems, the transient voltage characteristics of distribution network integrated with distributed generations is analyzed and studied in this paper. Such source models as the wind turbine, photovoltaic generation, fuel cell and battery, and the simulation model of IEEE33 bus medium-voltage distribution network are also built in this paper. Under different fault conditions, the impacts of such factors as distributed generation and capacity, permeability and accessing location of micro sources on the transient voltage characteristics of the distribution network are analyzed, and two main indexes, transient response recovering rate and relative voltage boosting rate, are proposed to quantify the transient voltage level and the transient voltage recovery rate. It can be seen from simulation results that the accessing of the distributed generation can significantly improve the transient voltage level of the distribution network which is also affected by the accessing location, and the increasing of permeability will extend the transient voltage recovery time accompanying with a significant shock.