Evaluation of Aggregators for Integration of Large-scale Consumers in Smart Grid

Utilization of consumers to mitigate the impact of increasing renewable resources
on power systems is one of the visions of future smart grids. Flexible consumers are consumers who can change their consumption patterns in such a way as to help the grid to tackle the balancing problem. In previous work, we proposed a hierarchical structure to provide regulating power to the grid by just utilizing the consumption units. The main focus of that work was on designing a centralized controller, a so-called aggregator, which is responsible for aggregating the flexibility in an optimal way. To accomplish the optimization, the aggregator requires a model which describes the behavior of each consumption unit. These models should be sufficiently simple to be used in the optimization task. However, simple models might not capture all dynamics and features of the real system. In this paper, we will evaluate the proposed set-up to understand to what extent the utilization of simplified models can lead to reasonable results. To this end, we will connect the aggregator to a complex and verified model of an actual supermarket refrigeration system which enables us to investigate the closed-loop behavior of the whole set-up.