Cyber Physical Energy Systems Modules for Power Sharing Controllers in Inverter Based Microgrids

The Microgrids (MGs) are an effective way to deal with the smart grid challenges, including service continuity in the event of a grid interruption, and renewable energy integration. The MGs are compounded by multiple distributed generators (DGs), and the main control goals are load demand sharing and voltage and frequency stability. Important research has been reported to cope with the implementation challenges of the MGs including the power sharing control problem, where the use of cybernetic components such as virtual components, and communication systems is a common characteristic. The use of these cybernetic components to control complex physical systems generates new modeling challenges in order to achieve an adequate balance between complexity and accuracy in the MG model. The standardization problem of the cyber-physical MG models is addressed in this work, using a cyber-physical energy systems (CPES) modeling methodology to build integrated modules, and define the communication architectures that each power sharing control strategy requires in an AC-MG. Based on these modules, the control designer can identify the signals and components that eventually require a time delay analysis, communication requirements evaluation, and cyber-attacks’ prevention strategies. Similarly, the modules of each strategy allow for analyzing the potential advantages and drawbacks of each power sharing control technique from a cyber physical perspective

Advanced Controls Of Cyber Physical Energy Systems

Cyber system is a fairly important component of the energy systems. The network imperfections can significantly reduce the control performance if not be properly treated together with the physical system during the control designs. In the proposed research, the advanced controls of cyber-physical energy systems are explored in depth. The focus of our research is on two typical energy systems including the large-scale smart grid (e.g. wide-area power system) and the smart microgrid (e.g. shipboard power system and inverter-interfaced AC/DC microgrid). In order to proactively reduce the computation and communication burden of the wide-area power systems (WAPSs), an event/self-triggered control method is developed. Besides, a reinforcement learning method is designed to counteract the unavoidable network imperfections of WAPSs such as communication delay and packet dropout with unknown system dynamics. For smart microgrids, various advanced control techniques, e.g., output constrained control, consensus-based control, neuro network and game theory etc., have been successfully applied to improve their physical performance. The proposed control algorithms have been tested through extensive simulations including the real-time simulation, the power-hardware-in-the-loop simulation and on the hardware testbed. Based on the existing work, further research of microgrids will be conducted to develop the improved control algorithms with cyber uncertainties

Synchrophasor Data Analytics for Control and Protection Applications in Smart Grids

RÉSUMÉ Des réseaux intelligents sont des réseaux d’énergie fortement distribués où les technologies d’énergie et des services sont intégrés avec des informations, des communications et contrôlent des technologies. Puisque les sources d’énergie renouvelable deviennent plus efficaces et rentables, les réseaux intelligents peuvent livrer la puissance propre, durable, sécuritaire, et fiable aux consommateurs. Cependant, l’utilisation rapide de sources d’énergie renouvelable provoque des défis techniques en termes de surveillance, le contrôle et la protection des réseaux électriques. En fait, l’énergie renouvelable implique les phénomènes qui sont naturellement stochastiques comme la lumière du soleil et le vent. Donc, les réseaux intelligents devraient être capables de surveiller et répondre aux changements tant dans fournisseur d’énergie que dans la demande. L’évolution des réseaux électriques provoque aussi le déploiement de nombreuses unités de mesure sans précédent et d’intelligents appareils de mesure. En vertu des systèmes de communications, les signaux en temps réel et les données peuvent être échangés entre les composants des réseaux intelligents. Le flux de données en temps réel fournit une occasion unique pour des applications axées sur les données et des outils pour démultiplier la modernisation de réseaux et la résilience. Les unités de mesure de phaseur sont les dispositifs spécialisés qui acquièrent le phaseur synchronisé (synchrophasor) des données des réseaux électriques. L’analytique de données Synchrophasor peut potentiellement étre plus performant que des méthodes traditionnelles en termes de prise de décisions. Spécifiquement, l’analytique de données est des approches qualitatives/quantitatives et les algorithmes qui rassemblent et traitent des données pour en fin de compte améliorer la conscience situationnelle dans des réseaux électriques. Motivé par ce fait, cette thèse présente des solutions viables pour l’analytique de données synchrophasor dans le but d’améliorer la surveillance, le contrôle et la protection de réseaux de distribution. La thèse se concentre sur trois fonctionnalités qui sont portées de basé sur l’analytique de données synchrophasor: Détection de perturbation centralisée, surveillance de production décentralisée (PD) et la protection “backup” coordonnée. L’objectif de surveillance de perturbation est de réaliser la détection rapide et fiable de tension/des déviations de fréquence qui affectent la stabilité de réseau. La surveillance de PD est liée à la détection de la présence/absence de ressources énergétiques pour la gestion du flux de puissance.----------ABSTRACT Smart grids are highly distributed energy networks where energy technologies and services are integrated with information, communications and control technologies. As renewable energy sources are becoming more efficient and cost–effective, the smart grids can deliver safe, clean, sustainable and reliable power to consumers. However, the rapid utilization of renewable energy sources brings about technical challenges in terms of monitoring, control, and protection of power systems. In fact, renewable energy involves phenomena which are naturally stochastic such as sunlight and wind. Therefore, the smart grids should be capable of monitoring and responding to changes in both power supply and demand. The evolution of the power systems also gives rise to deployment of unprecedented number of measurement units and smart meters. By virtue of communications systems, real-time signals and data can be exchanged between components of the smart grids. The flow of real-time data provides a unique opportunity for data-driven applications and tools to leverage grid modernization and resiliency. Phasor measurement units are specialized devices that acquire synchronized phasor (synchrophasor) data from the power systems. Synchrophasor data analytics can potentially outperform traditional methods in terms of decision making. Specifically, data analytics are qualitative/quantitative approaches and algorithms that collect and process data to ultimately improve situational awareness in the power systems. Motivated by this fact, this thesis presents viable solutions for synchrophasor data analytics with the aim of improving monitoring, control and protection of power distribution grids. The thesis focuses on three functionalities that are carried out based on synchrophasor data analytics: Centralized disturbance detection, monitoring of distributed generation (DG) systems, and coordinated backup protection. The objective of disturbance monitoring is to achieve fast and reliable detection of voltage/frequency deviations that affect the network stability. The DG monitoring is concerned with detecting presence/absence of energy resources for management of the flow of power. Disturbance and DG monitoring tools pave the way for adaptive backup protection of active distribution networks. The adaptive backup protection scheme ensures the post-fault stability by detecting line faults within a permissible tolerance time. The coordination between control and backup protection systems leads to fast recovery of voltage/frequency and minimizes power outage. The efficacy and reliability of the developed methods and algorithms are validated by extensive computer simulations based on different benchmarks

Efficiency and Sustainability of the Distributed Renewable Hybrid Power Systems Based on the Energy Internet, Blockchain Technology and Smart Contracts

The climate changes that are visible today are a challenge for the global research community. In this context, renewable energy sources, fuel cell systems, and other energy generating sources must be optimally combined and connected to the grid system using advanced energy transaction methods. As this book presents the latest solutions in the implementation of fuel cell and renewable energy in mobile and stationary applications such as hybrid and microgrid power systems based on energy internet, blockchain technology, and smart contracts, we hope that they are of interest to readers working in the related fields mentioned above

A Comprehensive Review of the State-of-the-Art of Secondary Control Strategies for Microgrids

The proliferation of distributed energy resources in distribution systems has given rise to a new concept known as Microgrids (MGs). The effective control of MGs is a crucial aspect that needs to be prioritized before undertaking any implementation procedure. This article provides a comprehensive overview of hierarchical control methods that ensure efficient and robust control for MGs. Specifically, it focuses on the secondary controller approaches (centralized, distributed, and decentralized control) and examines their primary strengths and weaknesses. The techniques are thoroughly discussed, deliberated, and compared to facilitate a better understanding. According to functionality, the hierarchical-based control scheme is allocated into three levels: primary, secondary, and tertiary. For secondary control level, the MG communication structures permit the usage of various control methods that provided the significance of the secondary controller for consistent and reliable MG performance and the deficiency of an inclusive recommendation for scholars. Also, it gives a review of the literature on present important matters related to MG secondary control approaches in relation to the challenges of communication systems. The problem of the secondary level control is deliberated with an emphasis on challenges like delays. Further, at the secondary layer, the distributed control techniques for reducing communication system utilization and then reducing communication system delays are conferred. Furthermore, the benefits and limitations of various control structures, such as centralized, decentralized, and distributed are also discusses in this study. Later a comparative analysis of entire control approaches, the best methods of control according to the author's perspective are also discussed