Dual-level consensus-based frequency regulation using vehicle-to-grid service.

Highlights • The dual-level control scheme can meet the frequency regulation requirement and the individual PEV charging requirements. • The consensus algorithm is applicable for distributed control areas and PEVs power coordination with limited communication: every control area/PEV only needs to exchange information among the neighboring control areas/PEVs instead of all the agents. • This method can be applied in real-time simulation. The optimal charging commands can be obtained and updated in every time step based on the current frequency deviation condition and electricity price. Abstract To coordinate plug-in electric vehicles (PEVs) to support the primary frequency control, this paper presents a dual-level consensus-based frequency control method. The upper-level control aims to minimize the frequency deviation of multi-area power system, and the lower-level control aims to minimize the frequency regulation cost and battery degradation cost for individual PEVs. The incremental cost functions are formulated based on the objectives of the dual control levels, in this case, no objective function needs to be solved, and instead, the optimal results can be achieved by reaching a consensus incremental cost among neighboring individuals. The graph theory is applied to build the communication network among neighboring control areas in upper-level control, and among neighboring PEVs in lower-level control. The consensus algorithm is applied to specify the information updating and exchange among neighboring individuals. In addition, the dynamic models of multi-area power system and PEVs are developed for controller implementation and investigation. The simulation with different case studies are conducted to validate the performance of the proposed dual-level frequency control. The simulation results show that, with limited communication, the connected PEVs can be efficiently coordinated via dual-level controller to provide primary frequency regulation service, and meanwhile meet the battery charging/discharging constraints. [ABSTRACT FROM AUTHOR]