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Summary: Electric power systems try to maximize resilience by various enhancement strategies as preventive and corrective actions against extreme weather events. This paper presents an operational network reconfiguration strategy during a high wind event to strengthen the resiliency of distribution networks. In the proposed resilience enhancement strategy, a bi‐level optimization problem is formulated with two conflicting objectives (i) maximizing grid resilience and (ii) realize the primary objective by a minimum number of out‐of‐service lines (OSLs) switching operations. Furthermore, the algorithm considers the priority of loads, which is an important characteristic of modern distribution grids. The optimization problem is solved by the bi‐level genetic algorithm (BiGA). The IEEE 33‐bus network is utilized to demonstrate the application of the developed algorithm. The simulation results show a significant improvement in the resiliency of the tested network and reveal that switching operations can be used effectively to increase the resiliency of distribution networks against natural disasters. Furthermore, sensitivity analysis is performed to show the effectiveness of the proposed approach for finding the global optimal point. The proposed network reconfiguration strategy helps to prepare for severe weather conditions. [ABSTRACT FROM AUTHOR]

With the capacity increase of large‐scale DC renewable energy and DC loads, the reliability issues of hybrid AC/DC networks become increasingly prominent. On the other hand, a modern distribution network should also deliver power to individual customers based on their priority levels and the traditional reliability indices are not suitable for modern networks. Flexible reliability (FR) is a new concept that considers the loads' importance in the reliability evaluation of distribution grids. In this study, a novel comprehensive FR index is introduced for hybrid AC/DC networks. To determine the proposed index, power networks are modelled as a topological combination of edges and nodes. An axiomatic design concept which is a systematic binary matrix‐based approach is then employed for topology analysis. The proposed index is based on the systematic counting of feasible paths from generators to loads, considering loads' importance. The effectiveness of the proposed index is demonstrated through an illustrative example and IEEE 33‐bus distribution system. [ABSTRACT FROM AUTHOR]

Power plant successful operation is always a function of its constituent sub-systems and components. Due to the current financial constraints in power industry, power plant operators are continuously facing a wide range of challenges when dealing with maintenance scheduling and asset management practices of the plant sub-systems. Knowledge on the roles and criticality of the constituent components on the plant overall performance will help in establishing the plans for its smooth, safe, and economic operation. To ensure making the techno-economical decisions on the maintenance of power plant equipment, this paper focuses on the reliability modeling of the combined cycle power plants (CCPP). Reliability models are first developed for the gas turbine power plants (GTPP) and steam turbine power plants (STPP) which provides the input to evaluate the reliability of the overall CCPP from an engineering system perspective. Reliability-oriented sensitivity indices are proposed the aforementioned types of power plants to identify the plant critical components, i.e., those with the most considerable influences on the system reliability and availability targets. Having the system critical components recognized, one can then decide on the efficient maintenance strategies for the power plant components so that the available resources can be well planned and allocated techno-economically. [ABSTRACT FROM AUTHOR]