An operating reserve risk map for quantifiable reliability performances in renewable power systems

This paper focuses on quantification of operating reserve requirement in power systems with high penetration of renewable resources. Built upon the recently introduced concept of dedicated operating reserve for renewable resources (termed as renewables reserve), we decompose the operating reserve into day-ahead portion and intra-day portion. The latter portion is determined and procured with closer-to-real-time forecast of renewable output after the closing of day-ahead market. Recognizing the inherent correlation between system reserve level and its reliability performances, we introduce a Risk Map as an intuitive tool for updating reserve levels with quantifiable reliability performances during the intra-day operation. The proposed procurement method prevents overly conservative deployment of operating reserves and uses less expensive units. It also provides evolving visualization of system reliability performances with updated information of renewable forecast each hour. Numerical simulation based on a modified IEEE Reliability Test System suggests the efficacy of the proposed method in providing cost-effective reserve levels in power systems with high levels of renewable resources.