Smart Grid Solutions Research Articles

Assessing the potential of MV automation for distribution network reliability improvement

Summary Distribution network automation is a key functionality in the evolution towards smarter electricity grids. The main driver to deploy this kind of smart grid solutions is the improvement of continuity of supply for network users; thanks to the fact that an enhanced network monitoring and telecontrol can improve the fault management process conducted by distribution system operators. However, the parameters that affect their successful implementation are not completely understood yet. Addressing this gap, this paper presents a detailed analysis to identify the main factors affecting the implementation of automation at medium voltage distribution networks and discusses the regulatory implications. Several realistic case studies are analyzed, corresponding to a number distribution networks that resemble the architectural characteristics representative of the European distribution grids in different contexts. Hence, the results allow deriving general conclusions that can be widely applicable to European distribution networks.

Scalability and replicability analysis of smart grids demo projects: An overview of selected European approaches

The modernization of the European electricity grids is a key priority of the European energy policy that must be achieved in order to safely integrate renewable and decentralized generation, improve energy efficiency, and integrate the active consumers in the energy system. Several European and National research programs are investigating new technologies and solutions aimed at addressing these challenges. In order to speed up the shift from the stage of industrial research to the market uptake of the most innovative solutions, new methods shall be defined to ensure that the solutions demonstrated can be scaled up and replicated. These methods need to address not only technical aspects, but also the non-technical issues such as public acceptance of grid infrastructures or new market designs and products by all stakeholders and to harmonize regulation and legal framework. This paper analyses and compares the different approaches developed by important EU projects such as GRID+, GRID4EU, and IGREENGRID, to investigate the scalability and replicability potential of the solutions tested in smart grids pilot projects. Barriers and enabling factors that might limit or support the large-scale deployment of innovative solutions are presented and discussed. One of the most important problems identified is the difficulty to build reliable models of the representative distribution networks needed in the analyses, which might hinder the replicability of a given solution. The existence of an EU-wide repository of distribution grid data would facilitate future work. Moreover, the development of common standards is advised to support the interoperability of the most promising solutions and to guarantee the industrial competitiveness. Further research efforts are still required to the smart grids stakeholders community to elaborate a comprehensive approach. However, the overview of methodologies reported in the present paper represents a useful support for the project leaders that have to perform the scalability and replicability analysis of new pilot projects or regulators and policy-makers pondering to enable or support smart grid solutions. To achieve this, this paper highlights best practices, drivers, simulation tools and barriers encountered by the different projects. These aspects are key elements that shall be considered and further analyzed to build a comprehensive approach to the problem.

Engineering Smart Grids: Applying Model-Driven Development from Use Case Design to Deployment

The rollout of smart grid solutions has already started and new methods are deployed to the power systems of today. However, complexity is still increasing as focus is moving from a single system, to a system of systems perspective. The results are increasing engineering efforts and escalating costs. For this reason, new and automated engineering methods are necessary. This paper addresses these needs with a rapid engineering methodology that covers the overall engineering process for smart grid applications—from use case design to deployment. Based on a model-driven development approach, the methodology consists of three main parts: use case modeling, code generation, and deployment. A domain-specific language is introduced supporting the use case design according to the Smart Grid Architecture Model. It is combined with the IEC 61499 distributed control model to improve the function layer design. After a completed use case design, executable code and communication configurations (e.g., IEC 61850) are generated and deployed onto compatible field devices. This paper covers the proposed rapid engineering methodology and a corresponding prototypical implementation which is validated in a laboratory experiment. Compared to other methods the proposed methodology decreases the number of engineering steps and reduces the use case design and implementation complexity.

Services enabler architecture for smart grid and smart living services providers under industry 4.0

For an industry 4.0 environment, the management and offering of services, falls over the construction of a stable and reliable sensor and actuator infrastructure. Industry 4.0 is undergoing increase advancement, infrastructure availability and public acceptance, mainly boosted by the Interconnected Things. The public acceptance drives an increase on investments, carrying an insurgence of companies competing with each other to gain market. Although lessening costs, this insurgence has brought heterogeneous infrastructures and solutions availability, challenging services providers. Among the challenges the security and different technology solutions support are of the most importance. The scattering of solutions and software code have to be conveniently gathered to avoid weak-points, eventually, a menace to be explored by hackers. This paper is a contribution in order to embraces those challenges in a new architecture framework able of supporting the creation of solutions for Smart Grid and Smart Living services providers under the industry 4.0 paradigm. The architecture framework design offers security, simplicity of implementation and maintenance, and is resilient to failures or attacks and technologically independent. Field tests are reported in order to evaluate key aspects of the proposed architecture.

Fiber-wireless for smart grid: A survey

Smart grid allows two-way communication between power utility companies and their customers while having the ability to sense along the transmission lines. However, the downside is such, when the smart devices are transmitting data simultaneously, it results in network congestion. Fiber wireless (FiWi) network is one of the best congestion solutions for smart grid up to date. In this paper, a survey of current literature on FiWi for smart grid will be reviewed and a testbed to test the protocols and algorithms for FiWi in smart grid will be proposed. The results of number of packets received and delay vs packet transmitted obtained via the testbed are compared with the results obtained via simulation and they show that they are in line with each other, validating the accuracy of the testbed.

Are the Current Smart Grid Concepts Likely to Offer a Complete Smart Grid Solution?

At present, the structure of power systems is greatly changing due to the penetration of decentralized generations. Although they encompass a high flexibility potential, their large-scale penetration interferes with the power system operation at all voltage levels. To get rid of this flaw and exploit their flexibility, different concepts like Virtual Power Plants, Microgrids and Cellular Approach have been introduced but still no solution is in sight. Under these conditions, it seems quite intriguing to find out whether these concepts are likely to offer a complete solution or not. This paper presents ten criteria to assess the complete Smart Grid solution and introduces a comprehensive evaluation system based on cloud-charts. The paper looks into the already existing solutions, which are respectively based on Virtual Power Plants, Microgrids and Cellular Approach concepts. The investigations have shown that none of these solutions meets all criteria necessary for a complete Smart Grid solution. Even a combination of different criteria fails to yield the desired results.

Consideration of the Impacts of a Smart Neighborhood Load on Transformer Aging

Smart grid solutions with enabling technologies such as energy management systems (EMSs) and smart meters promote the vision of smart households, which also allows for active demand side in the residential sector. These technologies enable the control of residential consumption, local small-scale generation, and energy storage systems to respond to time-varying prices. However, shifting loads simultaneously to lower price periods is likely to put extra stress on distribution system assets such as distribution transformers. Especially, additional new types of loads/appliances such as electric vehicles (EVs) can introduce even more burden on the operation of these assets, which is an issue that needs special attention. Such extra stress can cause accelerated aging of distribution system assets and significantly affect the reliability of the system. In this paper, the impact of a smart neighborhood load on distribution transformer aging is investigated. The EMS of each household is designed to respond to prices and other signals emitted by the responsive load serving entity within the relevant demand response strategy. An optimization framework based on mixed-integer linear programming is presented in order to define the EMS structure. Then, the equivalent aging of the distribution transformer is examined with a thermal model under different scenarios. The case studies that are presented indicate that the integration of EVs in residential premises may indeed cause accelerated aging of the distribution transformers, while the need to investigate the efficiency of dynamic pricing mechanisms is rendered evident.

The cellular approach: smart energy region Wunsiedel. Testbed for smart grid, smart metering and smart home solutions

The ongoing transition from a conventional energy supply towards an energy system based on renewable sources requires fundamental changes to the energy infrastructure. In particular, the move from centralized towards distributed power generation significantly increases the demand for ICT-based management and control. Today ICT-based energy management is mostly purely central, making the critical infrastructure of power supply sometimes inflexible and potentially vulnerable to (cyber-)attacks. Addressing these challenges, the future grid requires high automation and distributed intelligence on field level being able to work independently from a central system. Distribution grids are often sparsely monitored and a system wide upgrade of measuring technology is associated with high costs. However, information about load behavior at the nodes of a grid is essential for grid state identification and load forecasting. This paper shows the concept of load balancing and the related IT architecture for monitoring and control of distributed energy systems, where smart metering and smart home technologies play a key role in the smart grid of the future. Readers are invited to contribute to the research work and field laboratory of the University of Bayreuth, which is operated by an innovative utility company in Bavaria.

Power Network Reliability Evaluation Framework Considering OHL Electro-Thermal Design

Utilities continually investigate ways to optimize the utilization of their existing plant and improve their network's flexibility and resiliency to future uncertainties. With respect to overhead lines (OHL), smart grid solutions aim to increase adequacy through the implementation of probabilistic thermal rating (PTR), dynamic thermal rating (DTR) or novel high temperature low sag (HTLS) conductor technologies. At present, the risks related to these particular solutions, both for the OHL plant and the power network, are not quantified. This paper presents a novel methodology for power network reliability evaluation which integrates a network level sequential Monte Carlo algorithm with a detailed modeling of OHL. This integration facilitates a holistic evaluation of power network reliability as it considers the properties of OHL design technologies and their associated ageing risks. As a result, the network performance (adequacy) and plant risks (ageing) introduced by increased OHL capacities through PTR, DTR, and HTLS solutions can be objectively quantified. An application of the methodology is demonstrated using the IEEE-RTS 96 network which is assessed considering PTR-based OHL capacities.

Security Policy and Good Practice for Implementation of Smart Grid Solutions

Smart Grid is both a concept and a way to mitigate infrastructural deficiencies and counteract the effects of the growing demand for electrical energy. One of the ways ensuring an increase in power grid’s management efficiency is utilization of the latest communication solutions. Such solutions ensure reduced energy consumption and leveling cur ve of daily load, decreased losses and – thanks to automated energy balancing – increased transfer security. (Polityka bezpieczenstwa i dobre praktyki w implementacji rozwiązan inteligentnych sieci elektroenergetycznych). Slowa kluczowe: inteligentne sieci elektroenergetyczne, bezpieczenstwo cyfrowe, inteligentne opomiarowanie, polityka bezpieczenstwa.

Profitability of smart grid solutions applied in power grid

The idea of a Smart Grid solution has been developing for years, as complete solution for a power utility, consisting of different advanced technologies aimed at improving of the efficiency of operation. The trend of implementing various smart systems continues, e.g. Energy Management Systems, Grid Automation Systems, Advanced Metering Infrastructure, Smart power equipment, Distributed Energy Resources, Demand Response systems, etc. Futhermore, emerging technologies, such as energy storages, electrical vehicles or distributed generators, become integrated in distribution networks and systems. Nowadays, the idea of a Smart Grid solution becomes more realistic by full integration of all advanced operation technologies (OT) within IT environment, providing the complete digitalization of an Utility (IT/OT integration). The overview of smart grid solutions, estimation of investments, operation costs and possible benefits are presented in this article, with discusison about profitability of such systems.

Global Smart Grid Transferability: Insights from Europe, the U.S., and China

The paper tries to address the question of whether the smart grid solution can be transferred internationally, and explore the transferability of the smart grid across countries with three national comparisons: USA, Europe and China. A qualitative content analysis in which data (the academic papers) are coded in preparation for comparison and interpretation is chosen to find the similarities and differences of smart grid development in different national contexts. Trough a comparative analysis of the smart grid development in USA, Europe and China, this paper conducts a transferable framework of smart grid solution with global and local features.

Barriers and Solutions to Smart Water Grid Development.

This limited review of smart water grid (SWG) development, challenges, and solutions provides an initial assessment of early attempts at operating SWGs. Though the cost and adoption issues are critical, potential benefits of SWGs such as efficient water conservation and distribution sustain the development of SWGs around the world. The review finds that the keys to success are the new regulations concerning data access and ownership to solve problems of security and privacy; consumer literacy to accept and use SWGs; active private sector involvement to coordinate SWG development; government-funded pilot projects and trial centers; and integration with sustainable water management.

Ambivalence, designing users and user imaginaries in the European smart grid: Insights from an interdisciplinary demonstration project

The gradual implementation of smart grid solutions is accompanied by an increased concern amongst researchers and policymakers for the role of users in such systems. For smart grids to perform as expected, the role of users in electricity systems must change. One approach to technology-user relationships proposes that the chance of success increases through involving users in the design and development of technologies. This article reports on a research project that set out to involve what was perceived as active and competent users in the design of feedback technologies. We explore how users were imagined in the project, and how the idea of active user participation was shadowed by an ambivalent and paradoxical view of users as knowledge deficient and incompetent. The case illustrates how the boundaries between involving users and by-passing users becomes blurred. Through this, we contribute to the knowledge on how user imaginaries and future expectations influence research and innovation processes, illustrating how traditional models of knowledge deficiency can lead to minimal user engagement.

A Generic Holonic Control Architecture for Heterogeneous Multiscale and Multiobjective Smart Microgrids

Designing the control infrastructure of future “smart” power grids is a challenging task. Future grids will integrate a wide variety of heterogeneous producers and consumers that are unpredictable and operate at various scales. Information and Communication Technology (ICT) solutions will have to control these in order to attain global objectives at the macrolevel, while also considering private interests at the microlevel. This article proposes a generic holonic architecture to help the development of ICT control systems that meet these requirements. We show how this architecture can integrate heterogeneous control designs, including state-of-the-art smart grid solutions. To illustrate the applicability and utility of this generic architecture, we exemplify its use via a concrete proof-of-concept implementation for a holonic controller, which integrates two types of control solutions and manages a multiscale, multiobjective grid simulator in several scenarios. We believe that the proposed contribution is essential for helping to understand, to reason about, and to develop the “smart” side of future power grids .

Distributed Online Optimal Energy Management for Smart Grids

Traditionally, economic dispatch and demand response (DR) are considered separately, or implemented sequentially, which may degrade the energy efficiency of the power grids. One important goal of optimal energy management (OEM) is to maximize the social welfare through the coordination of the suppliers’ generations and customers’ demands. Thus, it is desirable to consider the interactive operation of economic dispatch and DR, and solve them in an integrated way. This paper proposes a fully distributed online OEM solution for smart grids. The proposed solution considers the economic dispatch of conventional generators, DR of users, and operating conditions of renewable generators all together. The proposed distributed solution is developed based on a market-based self-interests motivation model since this model can realize the global social welfare maximization among system participants. The proposed solution can be implemented with multiagent system with each system participant assigned with an energy management agent. Based on the designed distributed algorithms for price updating and supply–demand mismatch discovery, the OEM among agents can be achieved in a distributed way. Simulation results demonstrate the effectiveness of the proposed solution.

Smart Household Operation Considering Bi-Directional EV and ESS Utilization by Real-Time Pricing-Based DR

As the smart grid solutions enable active consumer participation, demand response (DR) strategies have drawn much interest in the literature recently, especially for residential areas. As a new type of consumer load in the electric power system, electric vehicles (EVs) also provide different opportunities, including the capability of utilizing EVs as a storage unit via vehicle-to-home (V2H) and vehicle-to-grid (V2G) options instead of peak power procurement from the grid. In this paper, as the main contribution to the literature, a collaborative evaluation of dynamic-pricing and peak power limiting-based DR strategies with a bi-directional utilization possibility for EV and energy storage system (ESS) is realized. A mixed-integer linear programming (MILP) framework-based modeling of a home energy management (HEM) structure is provided for this purpose. A distributed small-scale renewable energy generation system, the V2H and V2G capabilities of an EV together with two-way energy trading of ESS, and different DR strategies are all combined in a single HEM system for the first time in the literature. The impacts of different EV owner consumer preferences together with the availability of ESS and two-way energy trading capabilities on the reduction of total electricity prices are examined with case studies.

Optimizing Electric Vehicle Coordination Over a Heterogeneous Mesh Network in a Scaled-Down Smart Grid Testbed

High penetration of renewable energy sources and electric vehicles (EVs) create power imbalance and congestion in the existing power network, and hence causes significant problems in the control and operation. Despite investing huge efforts from the electric utilities, governments, and researchers, smart grid (SG) is still at the developmental stage to address those issues. In this regard, a smart grid testbed (SGT) is desirable to develop, analyze, and demonstrate various novel SG solutions, namely demand response, real-time pricing, and congestion management. In this paper, a novel SGT is developed in a laboratory by scaling a 250 kVA, 0.4 kV real low-voltage distribution feeder down to 1 kVA, 0.22 kV. Information and communication technology is integrated in the scaled-down network to establish real-time monitoring and control. The novelty of the developed testbed is demonstrated by optimizing EV charging coordination realized through the synchronized exchange of monitoring and control packets via an heterogeneous Ethernet-based mesh network.

Combined solar heat and power with microgrid storage and layered smartgrid control toward supplying off‐grid rural villages

AbstractA project has been initiated in South Africa to design, model, build, and evaluate an easy to install solar fueled combined heat and power (micro‐CHP) system to supply off‐grid rural villages and eco‐estate communities. This study describes the design of a model that offers a combined 3 kW peak electrical, 12 kW peak thermal, stand‐alone solar power technology solution with microgrid storage to deliver power, and heat when the sun is shining and after sunset (at night time). The CHP demand side management system manages power and heat distribution to individual households in a small rural village based on a proposed smart microgrid technology solution. The solution aims to balance the heat/power demand side requirements based on digital feedback on heat/power utilization patterns and user demand. Aspects of the micro‐CHP system microgrid control are discussed while a modular smartgrid solution is selected for smart microgrid applications.

Multi-objective attuned design of damping controllers using frequency-based functions in smart grids

Increasing expansion of power systems is accompanied by innovations in smart grid solutions to maintain system stability. This paper formulates the dual-dimensional supplementary damping controller (SDC) and accelerating power system stabilizer (PSS2B) design as a multi-objective optimization procedure including both performance and robustness criteria. In wide-area operation, PSS2B is used for damping low-frequency swings and maintaining the robustness of controller in a wide range of swing frequencies. A dual-dimensional controller model is employed for the SDC. The robustness requirement is procured by using the idea of pseudospectra to handle the changes of power system parameters and the time delay introduced by wide-area damping controller (WADC). The multi-objective optimization problem is solved using an improved non-dominated sorting genetic algorithm-II (INSGA-II) based on fuzzy decision making (FDM) method. Different simulations are carried out on a 4-machine 2-area test system in order to validate the effectiveness and robustness of the designed controllers.