Flexibility Exchange Strategy to Facilitate Congestion and Voltage Profile Management in Power Networks

This paper proposes a novel flexibility exchange strategy to facilitate the management of congestion issues and voltage profiles (e.g., avoiding voltage violation and reducing voltage fluctuation) via minimum participation from customers or aggregators. In the proposed approach, the expectation of voltage profiles and power flow is determined by network constraints and customer's requirement, and it is used to guide the estimation of network state toward the expected state so that the predefined expectation (regarding voltage profile and power flow) is fulfilled. Availability of flexibility exchange from customers is integrated in estimation process. Flexibility factors are proposed to constrain the variation of network variables including voltage, power consumption/generation and power How. A genetic algorithm based-optimisation procedure is applied to obtain the minimum power variation from customers (i.e., minimum power variation from customers) while the defined expectation and constraints of flexibility availability are met. The approach is tested out on two representative distribution networks and the results have demonstrated the feasibility of the proposed approach in obtaining optimal flexibility exchange strategy that meets the predefined requirement/expectation whilst involving the least power variation from customers.