Enhanced Voltage and Frequency Stability for Power Systems with High Penetration of Distributed Photovoltaic Generation

摘要

Distributed solar photovoltaic (PV) has shown a large-scale development in Germany with a total capacity of 22.5 GW connected to the low voltage networks in 2015. This paper deals with the quantitative assessment of the impact of a high penetration of small PV units embedded in distribution networks on the voltage and frequency stability of the larger interconnected system. In particular, the effect of the various requirements regarding voltage control, frequency control and active power control during contingency situations is analyzed using a fully-integrated EMT-type model for the PV power plant. Simulations on a representative benchmark test network are used to assess and quantify the overall impact and to identify appropriate measures to improve the voltage and frequency stability of the power system. Finally, the proposed improvements are evaluated considering the present developments in Germany.