Coordinating Multitype Frequency Response Resources of New Energy Power System in Unit Commitment

The undergoing transition to new energy-based power system has increased the risk of frequency instability. This paper proposes a novel Unit Commitment (UC) formulation that simultaneously coordinates energy production and the allocation of multiple types Frequency Response (FR) resources. The simplified FR model of generator units, wind power and controllable loads are unified, which allows the dynamics of multiple FR resources to be analytically integrated into the system frequency evolution. Furthermore, the system frequency safety constraints are derived and incorporated into a UC model. The optimization problem is solved iteratively through the Extended Cutting Plane (ECP) method. Several case studies are carried out on an improved IEEE-39 node system with the inclusion of FR requirements. The numerical results specify that the provision of multitype ancillary FR services in the scheduling process, can ensure system frequency dynamic safety, and drastically impact the overall system costs.