Impact of distributed generation on voltage stability

The research of practical operation of Distributed Generation (DG)and its impact to power network is increasing for a range of reasons. The voltage stability of a distribution network with DG is studied in the paper. According to different network interfaces and operating modes, DGs are classified into four different node types. Methods used to calculate and analyze their power flow are studied. The voltage stability condition has been derived based on analysis of solution existence of power flow distribution network. Combined with four types of DGs, simulations and analysis of the impact on the voltage stability indexes are studied. Results show that the voltage stability has been reduced by PV-type DGs, which should not be installed too much. But the voltage stability of distribution network can be improved by PQ-type DGs on different location and different capacity.