Wolfgang Friede

Investigations in low voltage distribution grids with a high penetration of distributed generation and heat pumps

This paper reviews regulations and issues in grids with high penetrations of distributed generation. The characteristics of the voltage profile with PV, HP and CHP systems are shown by simulations. Furthermore the influence on the voltage profile with combinations of those appliances is examined.

Comparison of current and future voltage regulation measures on German low voltage grids

The transition of the energy system in Germany leads to high numbers of CHP, HP and PV systems on low voltage grids. The voltage level is identified as the main issue regarding connection restrictions. This paper utilises a 2020 scenario of an exemplary low voltage grid to evaluate state of the art and possible future measures for voltage control in order to comply with EN 50160 boundaries. Undervoltage is identified as main issue. Demand side management of heat pumps leads to comfort reductions for end-users. The use of on-load tap-changers is identified as a low cost and highly effective solution that does not result in comfort issues.