Smart Microgrids: Overview and Outlook

The idea of changing our energy system from a hierarchical design into a set of nearly independent microgrids becomes feasible with the availability of small renewable energy generators. The smart microgrid concept comes with several challenges in research and engineering targeting load balancing, pricing, consumer integration and home automation. In this paper we first provide an overview on these challenges and present approaches that target the problems identified. While there exist promising algorithms for the particular field, we see a missing integration which specifically targets smart microgrids. Therefore, we propose an architecture that integrates the presented approaches and defines interfaces between the identified components such as generators, storage, smart and \dq{dumb} devices.Comment: presented at the GI Informatik 2012, Braunschweig Germany, Smart Grid Worksho

Robust optimization for energy transactions in multi-microgrids under uncertainty

Independent operation of single microgrids (MGs) faces problems such as low self-consumption of local renewable energy, high operation cost and frequent power exchange with the grid. Interconnecting multiple MGs as a multi-microgrid (MMG) is an effective way to improve operational and economic performance. However, ensuring the optimal collaborative operation of a MMG is a challenging problem, especially under disturbances of intermittent renewable energy. In this paper, the economic and collaborative operation of MMGs is formulated as a unit commitment problem to describe the discrete characteristics of energy transaction combinations among MGs. A two-stage adaptive robust optimization based collaborative operation approach for a residential MMG is constructed to derive the scheduling scheme which minimizes the MMG operating cost under the worst realization of uncertain PV output. Transformed by its KKT optimality conditions, the reformulated model is efficiently solved by a column-and-constraint generation (C&CG) method. Case studies verify the effectiveness of the proposed model and evaluate the benefits of energy transactions in MMGs. The results show that the developed MMG operation approach is able to minimize the daily MMG operating cost while mitigating the disturbances of uncertainty in renewable energy sources. Compared to the non-interactive model, the proposed model can not only reduce the MMG operating cost but also mitigate the frequent energy interaction between the MMG and the grid

Canonical Coalitional Games vs. Coalition Formation Games for Power Exchange Management of Networked Microgrids

The concept of networked microgrids, which refers to a cluster of microgrids connected with each other, has emerged in the literature as a consequence of the increasing development of renewable energy. Energy management systems have been developed for planning, monitoring and controlling the power exchange into networked microgrids. Their main components are optimization algorithms for power exchange management. Several optimization algorithms based on coalition formation games were proposed to minimize distribution and transformation power loss of networked microgrids. Unlike these approaches, this paper proposes a non-lineal model based on canonical coalitional game for power exchange management of networked microgrids. To show the performance of the proposed model, results of the model and results of an algorithm based on coalition formation games recently reported in the literature are com-pared with. The main conclusion of this work is, when the objective is to minimize total power losses, the problem of power exchange management of networked microgrids should be modelled as a canonical coalition games and not as coalition formation games.Sociedad Argentina de Informática e Investigación Operativ

Canonical Coalitional Games vs. Coalition Formation Games for Power Exchange Management of Networked Microgrids

The concept of networked microgrids, which refers to a cluster of microgrids connected with each other, has emerged in the literature as a consequence of the increasing development of renewable energy. Energy management systems have been developed for planning, monitoring and controlling the power exchange into networked microgrids. Their main components are optimization algorithms for power exchange management. Several optimization algorithms based on coalition formation games were proposed to minimize distribution and transformation power loss of networked microgrids. Unlike these approaches, this paper proposes a non-lineal model based on canonical coalitional game for power exchange management of networked microgrids. To show the performance of the proposed model, results of the model and results of an algorithm based on coalition formation games recently reported in the literature are com-pared with. The main conclusion of this work is, when the objective is to minimize total power losses, the problem of power exchange management of networked microgrids should be modelled as a canonical coalition games and not as coalition formation games.Sociedad Argentina de Informática e Investigación Operativ

Networked microgrid energy management based on supervised and unsupervised learning clustering

Networked microgrid (NMG) is a novel conceptual paradigm that can bring multiple advantages to the distributed system. Increasing renewable energy utilization, reliability and efficiency of system operation and flexibility of energy sharing amongst several microgrids (MGs) are some specific privileges of NMG. In this paper, residential MGs, commercial MGs, and industrial MGs are considered as a community of NMG. The loads’ profiles are split into multiple sections to evaluate the maximum load demand (MLD). Based on the optimal operation of each MG, the operating reserve (OR) of the MGs is calculated for each section. Then, the self-organizing map as a supervised and a k-means algorithm as an unsupervised learning clustering method is utilized to cluster the MGs and effective energy-sharing. The clustering is based on the maximum load demand of MGs and the operating reserve of dispatchable energy sources, and the goal is to provide a more efficient system with high reliability. Eventually, the performance of this energy management and its benefits to the whole system is surveyed effectively. The proposed energy management system offers a more reliable system due to the possibility of reserved energy for MGs in case of power outage variation or shortage of power.Peer ReviewedPostprint (published version