Monte Carlo assessment of customer voltage constraints in the context of CVR schemes

(paper accepted) Conservation Voltage Reduction (CVR) schemes are seen as promising techniques to deliver ancillary services, defer investments and provide energy savings. However, the benefits that might be unlocked are limited by the voltage variations that can be introduced without negatively affecting LV customers. This paper statistically quantifies this limit adopting a Monte Carlo approach on 57 UK LV feeders during winter. For this purpose, the percentage of BS EN 50160 non-compliant customers for different voltage levels on the primary side of the LV transformer is quantified. Results show that to maintain this figure below 1% the voltage on the primary side of every LV transformer should be maintained between 0.94 and 1 pu. Finally, the limitations imposed by these constraints are shown on a real UK MV network where the maximum voltage reduction for a specific day is also quantified.