  The increasing quantity of PV generation connected to distribution networks
is creating challenges in maintaining and controlling voltages in those
distribution networks. Determining the maximum hosting capacity for new PV
installations based on the historical data is an essential task for
distribution networks. Analyzing all historical data in large distribution
networks is impractical. Therefore, this paper focuses on how to time
efficiently identify the critical cases for evaluating the voltage impacts of
the new large PV applications in medium voltage (MV) distribution networks. A
systematic approach is proposed to cluster medium voltage nodes based on
electrical adjacency and time blocks. MV nodes are clustered along with the
voltage magnitudes and time blocks. Critical cases of each cluster can be used
for further power flow study. This method is scalable and can time efficiently
identify cases for evaluating PV investment on medium voltage networks.
