Risk-Averse Coordinated Operation of a Multi-Energy Microgrid Considering Voltage/Var Control and Thermal Flow: An Adaptive Stochastic Approach

Abstract

With an increasing penetration level of intermittent renewable energy sources and heterogeneous energy demands, the secure and economic operation of multi-energy microgrids (MEMGs) becomes more and more critical. Under this circumstance, this paper proposes an adaptive (two-layer) stochastic approach to obtain optimal MEMG operation decisions by taking advantage of distinct energy properties. First, rather than merely focusing on the active power economic dispatch, voltage/var control (VVC) scheme is involved to co-optimize the active and reactive power flow while guaranteeing voltage security; Second, a battery degradation model and a comprehensive thermal network model with thermal energy flow and transmission delay are presented to derive practical and efficient operations; Third, a conditional value-at-risk (CVaR)-based risk evaluation method is included to avoid over-optimistic solutions. The original nonlinear operation problem is reformulated as a mixed-integer linear programming (MILP) model to achieve high solution quality with acceptable computation performance. Finally, case studies are conducted to indicate that our proposed approach can effectively coordinate the dispatch of active/reactive power as well as thermal flow, thus ensuring system security with minimal operating costs and risks.