Software Defined Networks based Smart Grid Communication: A Comprehensive Survey

The current power grid is no longer a feasible solution due to ever-increasing user demand of electricity, old infrastructure, and reliability issues and thus require transformation to a better grid a.k.a., smart grid (SG). The key features that distinguish SG from the conventional electrical power grid are its capability to perform two-way communication, demand side management, and real time pricing. Despite all these advantages that SG will bring, there are certain issues which are specific to SG communication system. For instance, network management of current SG systems is complex, time consuming, and done manually. Moreover, SG communication (SGC) system is built on different vendor specific devices and protocols. Therefore, the current SG systems are not protocol independent, thus leading to interoperability issue. Software defined network (SDN) has been proposed to monitor and manage the communication networks globally. This article serves as a comprehensive survey on SDN-based SGC. In this article, we first discuss taxonomy of advantages of SDNbased SGC.We then discuss SDN-based SGC architectures, along with case studies. Our article provides an in-depth discussion on routing schemes for SDN-based SGC. We also provide detailed survey of security and privacy schemes applied to SDN-based SGC. We furthermore present challenges, open issues, and future research directions related to SDN-based SGC.Comment: Accepte

System configuration, fault detection, location, isolation and restoration: a review on LVDC Microgrid protections

Low voltage direct current (LVDC) distribution has gained the significant interest of research due to the advancements in power conversion technologies. However, the use of converters has given rise to several technical issues regarding their protections and controls of such devices under faulty conditions. Post-fault behaviour of converter-fed LVDC system involves both active converter control and passive circuit transient of similar time scale, which makes the protection for LVDC distribution significantly different and more challenging than low voltage AC. These protection and operational issues have handicapped the practical applications of DC distribution. This paper presents state-of-the-art protection schemes developed for DC Microgrids. With a close look at practical limitations such as the dependency on modelling accuracy, requirement on communications and so forth, a comprehensive evaluation is carried out on those system approaches in terms of system configurations， fault detection, location, isolation and restoration

Power Quality Concerns in Implementing Smart Distribution-Grid Applications

This paper maps the expected and possible adverse consequences for power quality of introducing several smart distribution-grid technologies and applications. The material presented in this paper is the result of discussions in an international CIGRE-CIRED joint working group. The following technologies and applications are discussed: 1) microgrids; 2) advanced voltage control; 3) feeder reconfiguration; and 4) demand-side management. Recommendations are given based on the mapping

Restoration of an active MV distribution grid with a battery ESS: A real case study

In order to improve power system operation, Battery Energy Storage Systems (BESSs) have been installed in high voltage/medium voltage stations by Distribution System Operators (DSOs) around the world. Support for restoration of MV distribution networks after a blackout or HV interruption is among the possible new functionalities of BESSs. With the aim to improve quality of service, the present paper investigates whether a BESS, installed in the HV/MV substation, can improve the restoration process indicators of a distribution grid. As a case study, an actual active distribution network of e-distribuzione, the main Italian DSO, has been explored. The existing network is located in central Italy. It supplies two municipalities of approximately 10,000 inhabitants and includes renewable generation plants. Several configurations are considered, based on: the state of the grid at blackout time; the BESS state of charge; and the involvement of Dispersed Generation (DG) in the restoration process. Three restoration plans (RPs) have been defined, involving the BESS alone, or in coordination with DG. A MATLAB®/Simulink® program has been designed to simulate the restoration process in each configuration and restoration plan. The results show that the BESS improves restoration process quality indicators in different simulated configurations, allowing the operation in controlled island mode of parts of distribution grids, during interruptions or blackout conditions. The defined restoration plans set the priority and the sequence of controlled island operations of parts of the grid to ensure a safe and better restoration. In conclusion, the results demonstrate that a BESS can be a valuable element towards an improved restoration procedure

Island operation capability in the Colombian electrical market: a promising ancillary service of distributed energy resources

Hoy en día, la mayoría de los generadores distribuidos no están diseñados para operar bajo condiciones de isla. El servicio complementario de capacidad de operación por islas se presenta como un servicio de soporte técnico con la capacidad de aumentar la resiliencia, confiabilidad, seguridad y flexibilidad de un sistema eléctrico de distribución. Sin embargo, la operación por islas presenta unos desafíos técnicos, económicos y sociales que deben discutirse y analizarse durante la etapa de planificación.En este artículo, se presenta una comparación entre una operación intencional por islas y una isla planificada previamente, así como una descripción de los principales desafíos y beneficios de la operación por islas. Además, se realiza una evaluación económica de la confiabilidad del servicio de energía eléctrica al implementar la capacidad de operación por islas como un servicio complementario. Dicha evaluación muestra que la operación por islas tiene el potencial de minimizar la energía no suministrada hasta en un 50%. Además, se muestra un análisis técnico para la implementación del servicio complementario de capacidad de operación por islas. Luego, se estudia un sistema eléctrico de distribución existente con pequeñas centrales hidroeléctricas como un estudio de caso, con el fin de identificar los requisitos técnicos establecidos tanto para el sistema de distribución como para la fuente de generación. Finalmente, y teniendo en cuenta las normativas y regulaciones vigentes, se esboza una propuesta para la implementación del servicio complementario de capacidad de operación por islas en el sistema eléctrico colombiano.Nowadays most distributed generators are not designed to operate under islanded conditions. The ancillary service of islanded operation capability is proposed as a technical support service with the ability to increase the reliability, security and flexibility of an electrical distribution system. Nevertheless, island operation entails technical, economic and social issues that must be discussed and analyzed during the planning stage.This article compares an intentional island project to a preplanned island and describes the main issues and benefits of islanded operation. Additionally, the reliability of the service to implement the islanded operation capability as an ancillary service is economically assessed, which shows that island-based operation has the potential to minimize non-supplied energy up to 50%. Also, a technical analysis of implementing island operation capability ancillary service is presented. Subsequently, an existing electrical distribution system with small hydropower plants is considered as a study case in order to identify the technical requirements set out for both, the distribution system and the generation source. Finally, taking into account the current Law and regulations, a proposal is outlined for the implementation of the island operation capability ancillary service in the Colombian electrical system

A Survey of Smart Grid Systems on Electric Power Distribution Network and Its Impact on Reliability

This paper presents an excerpt of a more comprehensive survey of smart grid systems on electric power distribution networks and its impact on reliability. The survey was carried out as part of the feasibility study in Nigeria to determine its enhance-ability on the smartness of a conventional (traditional) distribution network. A smart grid is not a single technology but multiplex technologies in which the combination of different areas of engineering, communication and energy management systems are done. Consequently, a comprehensive review of various approaches and their impact on reliability of the network is presented. Furthermore, this paper introduces the smart grid technology and its features, reliability impacts and emerging issues and challenges that arise from the smart grid system applications. The benefit of this comprehensive survey is to provide a reference point for educational advancement on the recently published articles in the areas of smart grid systems on electric power distribution network as well as to stimulate further research interest

The cost of active network management schemes at distribution level

The growth of wind generation in distribution networks is leading to the development of Active Network Management (ANM) strategies. ANM systems aim to increase the capacity of renewable and distributed generation (DG) that can connect to the network. In addition to DG, ANM schemes can also include storage devices and Demand Side Management (DSM) strategies. Currently ANM schemes are mainly part of network research and development programmes, funded through network innovation schemes. In future, ANM schemes will need to cover the costs of establishing such a scheme through payments from the network owners and the users of the network. This paper discusses the current charging arrangements which account for network upgrades and the access arrangements for wind farms connecting to networks which are close to capacity. The Orkney ANM scheme is used as a case study, where the costs of the implemented ANM scheme are compared to conventional network upgrades. In order to run ANM as a ‘business as usual’ case, there must be a way in which to recover the costs incurred in implementing and operating an ANM scheme on the network. These costs could be recovered through Use of System (UoS) charging, and there is an opportunity for domestic customers participating in an ANM scheme (through Demand Side Management, for example) to further reduce electricity bills by providing ancillary services to the network. ANM may increase the cost of electricity for domestic customers, however this increase can be considered substantially less than the cost incurred for significant network upgrades

Power quality and electromagnetic compatibility: special report, session 2

The scope of Session 2 (S2) has been defined as follows by the Session Advisory Group and the Technical Committee: Power Quality (PQ), with the more general concept of electromagnetic compatibility (EMC) and with some related safety problems in electricity distribution systems. Special focus is put on voltage continuity (supply reliability, problem of outages) and voltage quality (voltage level, flicker, unbalance, harmonics). This session will also look at electromagnetic compatibility (mains frequency to 150 kHz), electromagnetic interferences and electric and magnetic fields issues. Also addressed in this session are electrical safety and immunity concerns (lightning issues, step, touch and transferred voltages). The aim of this special report is to present a synthesis of the present concerns in PQ&EMC, based on all selected papers of session 2 and related papers from other sessions, (152 papers in total). The report is divided in the following 4 blocks: Block 1: Electric and Magnetic Fields, EMC, Earthing systems Block 2: Harmonics Block 3: Voltage Variation Block 4: Power Quality Monitoring Two Round Tables will be organised: - Power quality and EMC in the Future Grid (CIGRE/CIRED WG C4.24, RT 13) - Reliability Benchmarking - why we should do it? What should be done in future? (RT 15