Coordinating the operation of neighboring microgrids is a promising solution for the problem of growing penetration of renewable-based microgrids into the power system. In this paper, a hierarchical stochastic energy management system is proposed for operation management of interconnected microgrids. At the upper-level, a central entity is responsible for coordinating the operation of microgrids. Based on the energy scheduling made at this level, the power reference values to be exchanged within the microgrids network and between the microgrids and the main grid are calculated and communicated with the local energy management systems. At the lower-level, a decision making approach based on chance-constrained model predictive control is adopted for local operation management of each microgrid taking into account different sources of uncertainties. The results show that the proposed strategy provides the microgrids with the opportunity of exploiting maximum available capacity in the network. Consequently, the microgrids dependency on the main grid will be reduced and some important performance indices such as multi-microgrid system cost and real-time power deviations will be improved.

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An accurate model to represent the photovoltaic modules is essential to facilitate the efficient deployment of these systems in terms of design, analysis, and monitoring considerations. In this respect, this study proposes a new approach to improve the accuracy of the widely-used five-parameter singlediode model. Two new physical equations are introduced to represent the series and shunt resistances while the other parameters are represented by well established physical expressions. In the proposed model, most of the parameters are in terms of the cell temperature, irradiance, and datasheet values, while a few parameters need to be tuned. The model is compared with four well-known methodologies to extract the parameters of the singlediode and double-diode models. The simulation studies make use of the different I-V characteristics provided in the PVs' datasheets, characteristics extracted from an outdoor module, as well as the ones simulated with the software PC1D. The results show an improved precision of the proposed model to estimate the power characteristics for a wide range of temperatures and irradiances, not only in the MPP, but also in the whole range of voltages. Furthermore, the proposed physical model can be easily applied to other kind of studies where a physical meaning of the PV parameters is of great importance.

A regional network of microgrids includes a cluster of microgrids located in a neighbourhood area connecting together through power lines. In this study, the problem of operation management of networked-microgrids is considered. The main goal is to develop an efficient strategy to control local operation of each microgrid including the amount of energy to be requested from the main grid and the optimal charging/discharging patterns of batteries along with the transferred power among microgrids considering system's technical constraints. Accounting for system uncertainty due to the presence of renewable energy sources and variability of loads, the problem is formulated in the framework of chance-constrained model predictive control. Moreover, the Monte Carlo algorithm is adopted to generate discrete random scenarios to evaluate the solutions. Simulation studies have been exemplarily carried out in order to show the effectiveness of the proposed approach.

Several space organizations have been planning to establish a permanent, manned base on the Moon in recent years. Such an installation demands a highly reliable electrical power system (EPS) to supply life support systems and scientific equipment and operate autonomously in a fully self-sufficient manner. This paper explores various technologies available for power generation, storage, and distribution for space microgrids on the Moon. Several factors affecting the cost and mass of the space missions are introduced and analysed to provide a comprehensive comparison among the available solutions. Besides, given the effect of base location on the design of a lunar electrical power system and the mission cost, various lunar sites are introduced and discussed. Finally, the control system requirements for the reliable and autonomous operation of space microgrids on the Moon are presented. The study is complemented by discussing promising future technological solutions that could be applied upon a lunar microgrid.

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