Optimal Bidding Strategy and Intramarket Mechanism of Microgrid Aggregator in Real-Time Balancing Market

Microgrid (MG) system with multienergy resources has a wide and dispatchable generation range and shows instant response, therefore, constituting a potentially suitable real-time power balancing resource. In this paper, we introduce the concept of MG aggregator to involve small-scale MGs in real-time balancing market bidding via a hierarchical market framework. At the upper real-time market level, the bidding strategy of aggregator is optimized by a risk-constrained mean-variance model to depress the effects of renewable energy sources (RES) uncertainty; at the lower intramarket level, an event-driven mechanism is presented to reach the cleared quantity of the upper market while realizing maximum economy. Furthermore, the above-centralized self-scheduling problem of MG aggregator is decomposed into individual MG optimization problems to achieve an optimal solution with fast convergence. Simulation results verify that the proposed market framework and the bidding strategy for MG aggregator are of high applicability in real market environment.