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In this paper, supermarkets take the role of active consumers that fit into a Smart Grid context, as they have the potential flexibility to shift their energy consumption over time. The paper reviews a selection of promising cost and energy optimal control strategies potentially enabling supermarkets to become flexible consumers. The strategies are categorized either as indirect or direct depending the intended market commitment level. Further, a number of associated challenges are identified that need to be addressed in order to make a proposed strategy into a viable solution for large deployment. The intent is to promote a transition towards more intelligent use of energy in supermarkets and thus to help integrate more intermittent renawables in the electricity grid.

Smart grid applications belong to a diverse set of technologies, which combine behaviors and actions of all grid actors. Building such application is a challenging task requiring modeling, integrating, and validating different grid aspects efficiently. The design flow should adapt to the grid's requirements ranging from basic appliance functions to complex load scheduling algorithms and their integration's consequences. This paper tackles such challenges by proposing a framework to describe smart grid elements formally along with defining their interactions. The framework provides a smooth way for upgrading grid components independently and evaluate their performance. A case study utilizing an infrastructure of electric vehicles is demonstrated to validate the framework and prove its applicability in modeling smart grid applications. The case study enables a demand response service that provides a solution to the coordinated charging scheduling problem of electric vehicles.

In order to provide a comprehensive monitoring and controll infrastructure capable of fulfilling the requirements for security, control-ability and reliability of a modern Smart Grid, several factors for the adaptation of ICT technologies and architectures need to be considered. In this context Smart Grid systems operate on two time scales: first requiring delays in the order of μs for reporting events, e.g. short-circuits or component failures, and second data collection of the operational grid state from a huge number of sources, e.g. smart meters, sensors, etc., on the order of seconds to minutes. In this paper we focus on how network technologies can support this communication requirement of Smart Grid operation. Therefore, the focus is on reliability and control-ability of the network by providing the appropriate quality of service. For this purpose an overall heterogeneous communication architecture is presented, mapping the logical components and interfaces of multi-domain use cases to particular physical components and interfaces, which are implemented in testbeds and simulation models for assessment. Hereby, the major objective of the presented reference architecture is an unique definition of technical interfaces, components and information flows. It furthermore provides a framework for the specification of different technological options, information management and data aggregation. This work results in a novel approach for monitoring and controlling of energy distribution grids over heterogeneous communication networks is presented, which is based on two inter-related inner and outer control-loops for energy grid and communication network control. Furthermore, an application scenario is presented based on the integration of advanced meter reading and customer energy management systems into the overall architecture.

This paper focuses on reviewing grid connection of large offshore wind farms (OWFs) employing current state-of-the-art voltage source converter based high-voltage direct current (VSC-HVDC) technologies. A brief review of the VSC-HVDC evolvement is presented, followed by an overview of the advantages of employing VSC-HVDC for grid connection of large OWFs remotely located from the shore. A detailed description of the topologies is provided, and simulation results are presented in order to illustrate some of the main features of the most popular multi-level VSC-HVDC topology. Based on the review, it is found that there are currently three vendors of the VSC-HVDC. Furthermore, it is found that the VSC-HVDC is a promising technology for grid connection of remotely located OWFs and is going to be the preferred choice of remotely located OWF grid connection in e.g. the UK.

An analysis of structural model representation has been used to extract available inherent redundant information in the system. The paper presents a refined structured model representation based on bipartite directed graph definition and the necessary condition for sensor fusion based on the structural observability is proposed

The purpose of this paper is to develop a method to combine linear models with MLP networks, i.e. to find a method to make a nonlinear and multivariable model that performs at least as good as a linear model, when the training data lacks information. First, the MLP network for predicting the output from a dynamic system is described. Then two methods are proposed to combine linear and nonlinear modelling. The first method is the MLP network with linear path through, and the second method is a linear model with nonlinear error correction. Finally the two methods are tested. A thermal mixing process is used as a test system. This system is a multivariable and nonlinear process. The test is partly based on a simulation of the process and partly on data from a physical process. The results are given and discussed. >