Two-stage risk dispatch for combined electricity and heat system under extreme weather events

Extreme weather events can pose a significant risk to the combined electricity and heat system (CEHS). To mitigate the uncertain risk introduced by hurricanes and stochastic renewable energy sources (RES) outputs, a two-stage risk dispatch model for CEHS is proposed. The first stage is an emergency risk dispatch stage, which aims to retain the secure operation of CEHS while minimizing the cost of load curtailment. Here, the risk index is quantified to deal with uncertain component outrage. The minimum cost of load curtailment is defined as the objective function. Additionally, to describe the risk from uncertain components outrage, a margined momentbased ambiguity set is constructed. Furthermore, the worst-case conditional value at risk (WC-CVaR) approximation approach is applied to handle the distributional robust (DR) risk chance constraints. In the second stage, known as the regular risk dispatch stage, the DRCC (distributional robust chance constraints) is reformulated as the second order cone (SOC) constraint to minimize overlimit risks that may occur due to stochastic RES output. Vp (average risk probability) is proposed to quantify the level of risk involved in violating chance constraints. The case studies show that the risk coefficient epsilon highly influences Vp during the emergency risk dispatch stage when CEHS faces hurricane damage. Meanwhile, a higher value of epsilon leads to minimal dispatch cost but greater Vp in the regular risk dispatching stage.