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In electrical power systems, FACTS devices effectively control power flow and change bus voltages, leading to lower system losses and excellent system stability. The article discusses the research from the last decade that evaluated various methods for placing FACTS devices using the meta-heuristic approach to address the positioning of FACTS devices to maintain proper bus voltages and control line flow and improve the overall system efficiency. The need for more efficient electricity systems management has given rise to innovative technologies in power generation and transmission. The combined cycle power station is a good example of a new development in power generation and flexible AC transmission systems, generally known as FACTS, are controllers that improve transmission systems. Worldwide transmission systems are undergoing continuous changes and restructuring. They are becoming more heavily loaded and are being operated in ways not originally envisioned. Transmission systems must be flexible to react to more diverse generation and load patterns. In addition, the economical utilization of transmission system assets is of vital importance to enable utilities in industrialized countries to remain competitive and to survive. In developing countries, the optimized use of transmission systems investments is also important to support industry, create employment and utilize efficiently scarce economic resources. FACTS controller is a technology that responds to these needs. It significantly alters the way transmission systems are developed and controlled together with improvements in asset utilization, system flexibility and system performance. Several models and techniques suggest that devices can be placed in a particular location with different parameter settings. Finally, the optimization problem improved system performance by decreasing power loss, improving the voltage profile and power angle at each bus, raising the L-index, and minimizing generating costs. FACTS devices can increase the transmission line's capacity for transferring power by increasing the voltage at its terminals at both ends and reducing line reactance. The FACTS controller must be installed in the distribution and transmission lines to maximize the power flow. Various techniques are used for the best placement of FACTS controllers, including analytical methods, arithmetic programming approaches, meta-heuristic optimization approaches, and hybrid approaches—this paper analyses numerous analytical and meta-heuristic optimization techniques to place FACTS controllers in the most advantageous locations. The fundamental problems in intelligent power systems, such as improving stability, power quality, and managing congestion, are discussed in this study, along with several applications of FACTS devices. The cutting-edge power systems of today provide users with constant, high-quality power through smart grids and smart meters. [ABSTRACT FROM AUTHOR]

The intermittent nature of wind generation makes essential the development of new tools to support the security assessment of electrical power systems (EPS) with this type of alternative energy source. In this context, the static security region (SSR) is a powerful tool that allows the steady-state security assessment of a EPS through visual inspections. The nomograms enable to carry out a fast analysis of the possible generation scenarios that a system can assume without violating its security limits. Therefore, the mains objective of this paper is to include a new security limit in the SSR, to complement the security assessment. This new limit is associated with intermittent generation sources, such as wind farms. For that purpose, an algorithm for the automatic construction of SSR is presented, where this new security limit was incorporated. The proposed methodology is applied to the well-known New England test system. The results presented validate and indicate the effectiveness of the proposed technique. [ABSTRACT FROM AUTHOR]

False Data Injection Attacks (FDIAs) can bypass traditional state estimation detection, which threatens the security of power systems. Data-driven detection is an effective method for detecting FDIAs. However, for supervised detection methods, it is difficult to obtain a large number of anomaly labels in the power system. To address the issue of insufficient anomaly labels, this paper proposes an unsupervised FDIAs detection method based on graph autoencoder and graph attention neural network (GAE–GAT). In the method, the GAE aggregates the characteristics of topology and operation data in power system. To improve node representation, attention mechanism is adopted to aggregate adjacent node weights. This method is tested on the IEEE-14 and 118 bus systems for three scenarios: static topology, dynamic topology, and renewable energy integration. The results demonstrate that compared with previous unsupervised detection methods, the proposed method can greatly improve detection accuracy. [ABSTRACT FROM AUTHOR]

With the recent advancement in smart grid technology, real-time monitoring of grid is utmost essential. State estimation-based solutions provide a critical tool in monitoring and control of smart grids. Recently there has been an increased focus on false data injection attacks which can circumvent the traditional statistical bad data detection algorithm. Most of the research methodologies focus on the presence of FDIA in measurement set, whereas their exact locations remain unknown. To cater this issue, this paper proposes a deep learning architecture for detection of the exact locations of data intrusions in real-time. This deep learning model in association with traditional bad data detection algorithms is capable of detecting both structured as well as unstructured false data injection attacks. The deep learning architecture is not dependent on statistical assumptions of the measurements, it emphasizes on the inconsistency and co-occurrence dependency of potential attacks in measurement set, thus acting as a multilabel classifier. Such kind of architecture remains model free without any prior statistical assumptions. Extensive research work on IEEE test-bench shows that this scheme is capable of identifying the locations for intrusion under varying noise scenarios. Such kind of an approach shows potential results also in detection of presence of falsified data. [ABSTRACT FROM AUTHOR]

Due to the rapid increase of electricity demand and the deregulation of electricity markets, power systems tend to operate closer to stability boundaries. The scheme of preventive control should bring in a tradeoff between economics and security, which are often the two major inconsistent requirements for the daily operation of many power systems in the world. Optimal power flow (OPF) is a powerful tool to weaken the conflict between economy and security, but the main obstacle faced is that, the complexity involved for OPF with transient stability constraints is several orders of magnitude higher than that of conventional OPF with merely static constraints. Therefore, consideration of Transient Stability Constraints in Optimal Power Flow (OPF) problems is becoming more and more imperative. FACTS devices such as Thyristor Controlled Series Compensator (TCSC) can be very effective to power system security in case of a contingency. In this paper, we concentrate on the improving transient stability-constrained optimal power flow to against single contingencies via the use of TCSC. Study results on IEEE 30-bus system have proved the effectiveness of using TCSC to improve transient stability-constrained optimal power flow (TSCOPF). [ABSTRACT FROM AUTHOR]

Plug-in hybrid electric vehicles (PHEVs) are becoming more popular. The batteries of these electric vehicles may be charged from a standard outlet at home. These extra electrical loads have several impacts on distribution networks. This paper presents a methodology to quantify the impact that charging of different penetration levels of PHEVs may have on the security of distribution network. The network security is reflected through the well-known N-1 contingency analysis before and after charging PHEVs at home. The proposed methodology is applied to a realistic distribution network. The results show that network security may be remarkably degraded as the penetration of PHEVs increases. However, the extent of network security degradation largely depends on the charging period of PHEVs. As revealed by the results, daytime charging, from hour 06:00 to 14:00, may have the most adverse effect on the network security. [ABSTRACT FROM AUTHOR]

Generation and transmission unit outages cause MW line overloading and bus voltage magnitude violation problems in the remaining part of the system. This paper presents a new method for bus voltage magnitude screening for transmission line and transformer outages. Classification and ranking errors of sensitivity-based methods are overcome by imposing a non-linear constrained optimization module on the well-known linear feed-forward computational algorithms. Genetic algorithms are preferred as computation tool because of its implementation simplicity as well as for its parallel processing advantage in future computers. Accuracy of the method is tested on IEEE 57-bus test system and IEEE 118-bus test system. The results are compared with those of the full load flow to verify the strength of the method proposed in this paper. [ABSTRACT FROM AUTHOR]

The relevance of Discrete Event System theory (whether synthetic or analytic) to power system analysis and control is not clear. However, based on several characterizations of the domain of discrete systems set forth in the January 1989 Special Issue of the IEEE Proceedings, on “Dynamics of discrete event systems” (Ho, 1989), we attempt to delineate several power system control problems that may be amenable to analysis by DEDS methodologies. While the author is not qualified to judge whether the latter can speak to any of the examples, it may be relevant that in all cases the problems are non-trivial and in need of further contributions toward improved solutions, especially in view of the ongoing radical restructuring of the industry. The continuous process that is instantiated in the functioning of a power system is observed via three more or less diverse variables. Two of these, the scaler “system” frequency and the vector system voltage profile, are in principle mensurable physical phenomena; the third, system security, is a quality represented by a set membership conditioned on an inferred relationship between the two physical system variables and future realizations of one or more classes of autonomous stochastic phenomena. (These latter may be internal or external to the physical system, such as, e.g., respectively, equipment failure mechanisms and weather events.) [ABSTRACT FROM AUTHOR]

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