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Network reconfiguration is an effective way to avoid severe, large-scale power outages and to improve the resilience of active distribution networks (ADNs). Furthermore, the rapid development of distributed energy resources (DERs) provides new perspectives for network reconfiguration. In this paper, the effect of network reconfiguration and DER collaboration on ADN's resilient restoration are studied. The applications of DERs are fully explored. In order to achieve a better resilient performance, a detailed multiperiod model considering both reconfiguration and multiple DERs is established. Some linearization techniques are used to simplify the proposed model. Then, we build a rolling horizon optimization framework to solve the model. The framework eliminates the adverse effect of prediction errors and speeds up the calculation. By introducing predictions into strategy determination, the framework achieves a better restoration effect than the traditional greedy method. The proposed framework is tested on a 33-bus system. The simulations verify the efficiency of our work. [ABSTRACT FROM AUTHOR]

To better understand the thermal hydraulic characteristics of the parabolic trough solar field (PTSF), a comprehensive thermal hydraulic model (CTHM) based on a pilot plant is developed in this paper. All of the main components and thermal and hydraulic transients are considered in the CTHM, and the input parameters of the model are no longer dependent on the total flow rate. In this paper, we solve the CTHM by a novel numerical approach based on graph theory and the Newton-Raphson method, and then examine it by two tests conducted based on a pilot plant. Comparing the flow rate, temperature, and pressure drop results show good agreement and further validate the availability and accuracy of the CTHM under hydraulic and thermal disturbance. Besides, two applications of the CTHM are implemented for presenting its potential function. In the first application, two cases are simulated to reveal how the thermal effects influence the PTSF behavior, and in the second application, the CHTF is used for the study of control strategies under uniform and nonuniform solar irradiance. The results verify the feasibility of controlling the PTSF outlet temperature through the header and loop valves. [ABSTRACT FROM AUTHOR]

A thermal energy storage system is a critical component in concentrating solar power plants (CSPP), owing to which concentrating solar power (CSP) has superiorities over photovoltaic and wind power. Currently, the sole thermal energy storage (TES) system which is commercially applied to parabolic trough solar power (PTSP) plants worldwide is the two-tank indirect TES. In this study, the dynamic models of a solar field (SF), a two-tank indirect TES system, and a steam generation system (SGS) in a PTSP plant were developed and validated. Control and operation strategies on a clear day and a cloudy day were provided, and the dynamic simulations of the coupled operation using actual meteorological data were conducted. The influence of the two-tank indirect TES system on the dynamic characteristics of SGS on a system level was analyzed. Other key parameter variations were also presented. The results show that during the transition from the charge to the discharge process, the steam parameters slowly decrease. The variation of the molten salt height is further affected by the molten salt mass flow rate at the inlet and outlet of the molten salt tank. We adopted the PI control to adjust the thermal oil mass flow rate, thermal oil temperature, and water height. The developed dynamic models are useful in guiding system operation and control. [ABSTRACT FROM AUTHOR]