Impact of Distributed Photovoltaic Generation on Power System Dynamics

Solar photovoltaic (PV) is fast becoming one of the leading renewable energy sources in Germany with the overall installed capacity reaching 39 GW in 2015. This paper deals with the quantitative assessment of the impact of the PV units embedded in distribution networks on the dynamic behavior of the larger interconnected system. In particular, the effect of the various grid code and statutory requirements regarding voltage control, frequency dependent disconnection and active power control during contingency situations is analyzed using an EMT-type model for the PV power plant. Simulations on a representative test network and analysis of different operational scenarios were used to assess and quantify the overall impact and to identify possible improvements in the control system as well as in the applicable grid codes.