Droop controlled operation of heat pumps on clustered distribution grids with high PV penetration

In this work the impact of a high penetration of air to water heat pumps and PV plants on the distribution grid in residential areas is investigated. Results show that increasing PV penetration increases the hours of critical states in the distribution grid. Air to water heat pumps reduce those effects slightly when they are added to the grid. With an increasing penetration of heat pumps new problems, such as load peaks in the mornings, arise. By integrating voltage dependent droop control into the heat pumps, the negative effects on the distribution grid can be reduced. This reduction comes with a loss of HP efficiency and shows strong seasonal variability. For this study a set of representative grid layouts is used. Electric and thermal load profiles for each house are generated using the synPRO stochastic bottom-up model. The thermal load is covered by variable speed electric heat pumps combined with thermal storage. Resulting electric loads are used as input for a probabilistic load flow model.