Power Systems

Setting and formulating system design problems into mathematical optimization problems is not always straightforward especially when constraints associated with the system components are not clearly defined or well known. In this paper, the authors propose a methodology based on the Pareto front analysis in order to help designers to solve this kind of problems. This approach is directly applied to the optimization of an aircraft electrical system.

In the development of the electricity grid, Demand Response is a current subject of research for reasons of robustness, efficiency and renewable energy integration. Among the aspects of Demand Response, dynamic pricing is critical, and real-time pricing is a favored way of implementing it. The efficiency of such methods would however rely crucially on the ability and willingness of the end-user to react to varying prices. For this reason, we look at the problem of automatically scheduling the appliances that a user needs to run when the energy price is sent by the provider. We propose a discretetime formulation for this problem, show how it can be solved by a minimum cut algorithm and compare it with previously proposed techniques. Compared to an exact method requiring a mixed integer programming solver, our approach produces solutions very close to optimal in shorter running times and does not require proprietary software.

Electric trains inject a large amount of harmonics to the power network and consume high reactive power which makes them one of the worst loads kinds to be used in the power systems. These loads have non-linear characteristics and cause harmonic distortion. Filtering is one of the common ways utilized to eliminate harmonics and compensate reactive power. Filters are categorized in three types: passive, active and hybrid. Both passive and active filters have their own deficiencies while hybrid filters benefit from advantages of both former filters while overcoming their deficiencies. In this paper, active, passive and hybrid filters are discussed and then a suitable hybrid structure is introduced. Thereupon a harmonic model of an intercity electric train is presented and application of the proposed hybrid filter structure to the train is simulated using MATLAB/SIMULINK. The obtained results demonstrate the effectiveness of utilization of such hybrid filter structure in elimination of...

Power flow and state estimation are fundamental processes in the operation and planning of power systems. This paper presents a brief review, implementation, and evaluation of these techniques on a benchmark IEEE three-generator, six-bus network. The Newton-Raphson method is employed to solve the nonlinear AC power flow equations, with results validated against industrial software (PSSE). Additionally, weighted least squares algorithms were implemented for both DC and AC models. While the DC estimator achieved an acceptable residual of 5.57 MW in active power estimation, it still exhibited measurable accuracy loss on high-R/X or voltage-deviation branches, with line-flow mean absolute percentage errors increasing by ∼1-3% and bus angle deviations reaching up to 19 • relative to AC estimator results. Ultimately, an overview of how classical estimation and analysis techniques can be practically applied and evaluated for both industrial and benchmarking purposes in power systems engineering are presented and discussed in detail.

This paper discusses and compares three types of undervoltage load shedding closed-loop controllers in terms of performances and design computational effort. We first describe the various controllers and iden tifythe parameters to be optimized. Next, w epresent an optimization methodology applicable to all three types of controllers. This approach allows to find the controller parameters which optimize an overall performance objectiw. Results are presented on the Hydro-Qukbec system, in which load shedding is presently planned.

This bachelor's thesis presents a comprehensive simulation and performance analysis of a synchronous generator excitation system, focusing on the IEEE Type ST1A model. The study aims to evaluate the dynamic response and stability of the system under various operating conditions. By using a simulation approach, this work explores how the IEEE Type ST1A model influences the overall performance of the synchronous generator, providing valuable insights for the field of electrical engineering.

Technological innovation is the overall focus of NASA's Small Business Innovation Research (SBIR) program. The program invests in the development of innovative concepts and technologies to help NASA's mission directorates address critical research and development needs for agency projects. NASA's Small Business Innovation Research (SBIR) program focuses on technological innovation by investing in development of innovative concepts and technologies to help NASA mission directorates address critical research needs for Agency programs. This report highlights 15 of the innovative SBIR 2014 Phase I and II projects that focus on one of NASA Glenn Research Center's six core competencies-Power, Energy Storage and Conversion. The technologies cover a wide spectrum of applications such as high-radiation-tolerant ceramic voltage isolators, development of hermetic sealing glasses for solid oxide fuel cells, rechargeable lithium metal cells, high-efficiency direct methane solid oxide fuel cell systems, Li metal protection for high-energy space batteries, isolated bidirectional direct current converters for distributed battery energy applications, and high-efficiency rad-hard ultrathin Si photovoltaic cell technology for space. Each article describes an innovation and technical objective and highlights NASA commercial and industrial applications. This report provides an opportunity for NASA engineers, researchers, and program managers to learn how NASA SBIR technologies could help their programs and projects, and lead to collaborations and partnerships between the small SBIR companies and NASA that would benefit both.

A Sliding Mode Controller (SMC) is adopted in this work with a Proportional Integral Derivative (PID) to employ instead of Power System Stabilizer (PSS). The major proposal is that the effective property of PID and high characteristics of SMC are combined to eliminate the chattering effect of SMC in order to generate best control signal to the excitation system. The robust design of SMC-PID has been employed to enhance the power system stability and further to damp out strongly the system oscillations that caused by the disturbances. The proposed proposition is evaluated on Single Machine Infinite Bus (SMIB) power system under different perturbations with prespecified operating condition. The simulation results have demonstrated the high performance of mentioned controller that attained best results compared to various controllers. Keywords— PID, Power system stability, PSS, SMC, SMIB power system.

U radu se daje osvrt na najbitnije razlike u nacionalnim regulativama koje definišu oblast energetske efikasnosti zgrada, u Srbiji, Makedoniji, Crnoj Gori i Albaniji, dakle na tržištima za koje je objavljen softver „KnaufTerm2“, u verzijama programa prilagodjenim lokalnim osobenostima, i to sa aspekta energetske sertifikacije, dozvoljenih vrednosti koeficijenata prolaza toplote i tretmanu linijskih transmisionih toplotnih gubitaka.The paper provides an overview of the most important differences in national regulations that define the area of energy efficiency in buildings, in Serbia, Macedonia, Montenegro and Albania, countries for which software "KnaufTerm2" is released, in versions adapted to local characteristics, in terms of energy certification, allowable values of the coefficient of heat transfer and the treatment of linear transmission heat losses

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

In this study, determination of the optimal proportional-integral-derivate (PID) parameters with Gravitational search algorithm (GSA) for automatic generation control (AGC) of the two area non-reheat thermal power system is proposed. GSA is applied to search for the optimal PID controller parameters to minimize various performance indexes. The designed PID controller with the proposed approach is simulated under variety of operating conditions. Simulation results are shown that dynamic performance of the two area non-reheat thermal power system is improved by the designed PID controller with the proposed approach.

This article is concemed with the optimal dispatch of generating units of Itaipu, the world's largest hydroelectric plant in op- eration. Itaipi is a 12.6 GW hydro plant, located on the Parana river in South America, composed of 18 identical 700 MW generating units. A dynamic programming model has been developed to optimize the num- ber of generating units in operation at each hour of the day in order to attain the total generation scheduling of the plant in the most economic way. The model highlights the trade-off between start-up/shut-down of generating units and hydro power efficiency, taking into account varia- tions in tailrace elevation, penstock head losses, and turbine-generator efficiencies. The methodology has been tested for a typical generation scheduling, and the results show that the number of the tur- bine-generator sets dispatched has a major influence on the overall hydroplant efficiency, and therefore it is a key aspect to be considered in the dispatch of hydro generating units. In the case of Itaipu, the eco- nomic benefits, in terms of greater power efficiency with respect to ac- tual operation, are in the range of millions of dollars per year.

Forecasting the future load growth of an area based on its load demand is often a proactive measure to ensure a steady electricity power supply to that area. The study focused on long-term load forecasting for power system planning, specifically examining the electric load demand from consumers on distribution transformers within Port Harcourt City, located in Rivers State, Nigeria. The study encompassed a comprehensive review of both statistical and artificial intelligence-based approaches. Historical load data for distribution transformer readings spanning 2008 to 2017 were acquired from the Port Harcourt Electricity Distribution Company (PHEDC) and subjected to analysis using the curve-fitting technique. For the period between 2015 and 2030, a yearly load forecast simulation was conducted using the Fourier Series model, implemented with MATLAB software. This simulation aimed to provide insights into future load demand, facilitating careful and informed decision-making in the investment, operation, and maintenance of power system equipment. The effectiveness of the forecasting investigation was assessed using the Root Mean Square Error (RMSE), confirming the efficiency, reliability, and validity of the employed model. The study's forecasted results are presented as a valuable guide and practical tool for policymakers and the utility company (PHEDC) to enhance proper planning and decision-making processes. Considering the observed trend in the results, it is suggested that installing additional transformer units in the region would be necessary to alleviate the loads on existing overloaded transformer units within the power system network.

This work presents the results of a study on the doubly-fed induction generator (DFIG)
operating in generator mode. The main objective is to highlight the relevance of using a
wound-rotor asynchronous generator for electricity production in isolated sites.
A first part covers the general aspects of asynchronous machines: their structure, operating
principle, and both motor and generator regimes. The second chapter focuses on modeling the
DFIG in the Park reference frame linked to the rotor, leading to a usable generator model
(GADA).
The third chapter addresses parameter identification and estimation of external characteristics.
Experimental measurements yielded a stator resistance of 36.4 Ω, a rotor resistance of 6.64 Ω,
and inductances of 0.00621 H and 0.00276 H respectively. These values were incorporated
into a Matlab/Simulink simulation model.
The obtained results show a strong correlation between the experimental and simulated active
and reactive power curves, validating the proposed model. This study demonstrates the
efficiency and stability of the GADA in standalone operation for small-scale electricity
generation.
Keywords: asynchronous generator, doubly-fed induction machine, modeling, electrical
parameters, Matlab simulation, islanded operation, active power, reactive power.

Difference between failures, outage, Interruptions -causes of Long Interruptions -Origin of Interruptions -Limits for the Interruption frequency -Limits for the interruption duration -costs of Interruption -Overview of Reliability evaluation to power quality, comparison of observations and reliability evaluation. Short interruptions: definition, origin of short interruptions, basic principle, fuse saving, voltage magnitude events due to re-closing, voltage during the interruption, monitoring of short interruptions, difference between medium and low voltage systems. Multiple events, single phase tripping -voltage and current during fault period, voltage and current at post fault period, stochastic prediction of short interruptions. Voltage sag -definition, causes of voltage sag, voltage sag magnitude, and monitoring, theoretical calculation of voltage sag magnitude, voltage sag calculation in non-radial systems, meshed systems, and voltage sag duration. Three phase faults, phase angle jumps, magnitude and phase angle jumps for three phase unbalanced sags, load influence on voltage sags. Voltage sag -equipment behaviour of Power electronic loads, induction motors, synchronous motors, computers, consumer electronics, adjustable speed AC drives and its operation. Mitigation of AC Drives, adjustable speed DC drives and its operation, mitigation methods of DC drives. Overview of mitigation methods -from fault to trip, reducing the number of faults, reducing the fault clearing time changing the power system, installing mitigation equipment, improving equipment immunity, different events and mitigation methods. System equipment interface -voltage source converter, series voltage controller, shunt controller, combined shunt and series controller.

RESUMEN: Los sistemas de diagnóstico de fallas en empresas asociadas al sector eléctrico requieren propiedades de precisión y flexibilidad cuando surgen eventos de falla. Actualmente existen sistemas que pretenden mejorar el proceso de diagnóstico mediante varios métodos y técnicas computacionales, reduciendo el tiempo de respuesta a perturbaciones. Sin embargo, son pocas las propuestas que unifican modelos gráficos de conocimiento con las señales de un proceso que pueden ofrecer dispositivos como controladores lógicos programables (PLCs). Este artículo propone un software novedoso guiado por modelos basados en redes de Petri e integrado con señales del proceso, para el diagnóstico de falla en centrales de generación eléctrica. Un caso de estudio demuestra la flexibilidad y adaptabilidad del software cuando nuevas nociones en los modelos de conocimiento cambian, sin realizar procedimientos de reingeniería al software. PALABRAS CLAVE: diagnóstico de fallas, redes de Petri, desarrollo de software, modelos de conocimiento, sistemas de energía, automatización.

Description/Abstract A mobile 480-V, 2-MVA UPS System utilizing battery energy storage was installed at S and C Electric Company's Polymer Products Fabrication Building in Chicago, Illinois in May 1999 to provide uninterrupted power to the building for up to 15 ...

Energy storage is inherently a flexible asset that can be used to reduce renewable energy curtailment and the congestion at its host network, enhance system resilience, and provide ancillary services at peak times. But the cost of technology still hampers the large-scale adoption of storage in power distribution networks. With EV parking lots included in its asset portfolio, a city can take advantage of the power stored in the parked EVs without major capital investments. In this article, we formulate the operation of an EV parking lot from the viewpoint of its owner (i.e., a city or a private entity). The lot works as a market aggregator with operational uncertainties stemming from: (i) random arrival and departure of vehicles, (ii) the SoC of EV batteries at the times of arrival and departure, and (iii) willingness of EV owners to participate. The risks from these uncertainties and market prices of ancillary services impact the bottom line of the lot owner's revenue. For EV owners the excessive up and down cycles of battery is offset by discount offered by the lot owner. We provide an illustrative example and a roadmap to extend this model to take the holistic view of a power distribution network.

• TABLE OF CONTENTS ABSTRACT RÉSUMÉ ACKNOWLEDGEMENTS TABLE OF CONTENTS LIST OF SYMBOLS LIST OF TABLES LIST OF FIGURES LIST OF ABBREVIATIONS ii iv vi vii xii xix xxii xxvii CHAPTER 1 INTRODUCTION 1 l.l General • 1.2 The Present Thesis 3 1.2.1 Outline of the Thesis 5 1.2.2 Claim of Originality CHAPTER 2 TABLE OF CONTENTS xi APPENDIX B MATRIX FORMULATION AND DERIVATIVES 232 RI Power Injections and Power Flows in Matrix Form B.2 Derivatives of the Complex Power Injections B.2.1 First Order Derivatives of S R2.2 Second Order Derivatives of S B.3 Derivatives of the Power Flows

The growth in the demand for electricity in Libya during the last decade witnessed a dramatic growth in the national's annual residential development has played a major role in boosting the demand for electric power. The domestic sector in Libya already accounts for approximately 39 percent of electricity demand. To meet the projected demand for electrical power to cope with, the development plans, increases in the population and the rising in the living standards, government will have to accomplish new power generating units. Comparing with the high budget of constructing new generating power units, load management system it would be attractive resource that should be seriously considered as an important part of national energy program, where demand growth rate exceeds the supply since it is playing an increasing role around the world as a valuable and cost effective energy resource. Hence, was light projecting on power load management program, for its benefit in reducing the e...

This paper presents a case study describing the impact of charging process of plug in hybrid vehicles (PHEV) and all electrical vehicles (EV) on the supply grid. The paper shows the distortion produced in the grid by the simultaneous charge of a large fleet of vehicles and the corrective actions taken to guarantee the Electromagnetic Compatibility with other loads in the same grid. The goal of the investigation was to establish a design guide for parking facilities

Computer simulation is a first logical step before taking a project to physical construction beside it is a powerful tool in energy network design. Combined systems are used to improve availability for energy supplied by renewable systems. The main inconvenient of some renewable energy sources is their highly seasonal nature, with great variations over time that can impede their use as the basis for consumption and limits them to peak demand times. The aim of this work is to simulate to verify the energetic sufficiency of a family house with renewable energies (wind, solar-photovoltaic) using a hybrid system of batteries and hydrogen. For that, Simulink®-Matlab® program was used considering meteorological data provided by CINAM (Galician Center for Environmental Research and Information). The model can be applied to determine the feasibility of implementing an energy network in specific places, and to predict energy flows and system behavior throughout the year.

In high voltage (HV) electrical power system, variety of solid, liquid and gaseous materials are used for insulation purpose to protect the incipient failure inside the HV power equipment. Among these the solid insulation is widely used for high voltage power equipment HV electrical power system. Most of insulating materials are not perfect in all respect and contains always some impurities. The presence of air bubble is one of such impurities in insulating materials and highly undesirable for such type of insulation which causes a local weak zone inside the insulator. Insulation of the HV power equipment gradually degrades inside the insulator due to cumulative effect of electrical, chemical and thermal stress. Due to the high voltage stress the weak zone inside the insulator causes the partial discharge (PD) which is known as local electrical breakdown. As a result the insulation properties of such materials are enormously degrades its quality due to the PD. In this work, the simulation of PD activity due to presence of a small cylindrical void inside the solid insulation material of high voltage power equipment is studied with the MATLAB Simulink platform.

This paper describes a new concept of automated fault analysis where fault transients and changes in power system equipment contacts are processed on-line. This allows faster confirmation of correct equipment operation and detection of unexpected equipment operations, as well as increased accuracy of fault location and analysis. In addition, the paper gives three independent utility examples that required automating some aspect of the fault analysis process. One approach is the substation level analysis, where local digital fault recorder (DFR) data is processed at the substation to obtain accurate fault location and analysis. Another approach is DFR data analysis at the master station location, where all DFR data files from remote locations are concentrated and processed. Finally, an example of a highly accurate fault location system for series compensated lines using global positioning system (GPS) synchronization is presented. This paper presents summary of the main accomplishments for each of the projects.

This paper proposes a new tool for analysis of power system disturbance. The information from proposed analysis method is useful to many control, operation and protection applications such as reliability analysis, asset management and outage management. Development of automated disturbance analysis and fault location software is introduced. Concerns in implementation, including source of data, communication requirements and standardization are also discussed.

The concept of Supervisory Control and Data Acquisition (SCADA) system was introduced in the late sixties and subsequently the Energy Management System (EMS) solution with set of functionalities that relied on SCADA data was introduced in the seventies. This EMS design was based on the notion that power system goes through distinct states such as normal, alert, emergency and restorative, and hence the EMS functionalities need to support operators’ ability to monitor the system behaviour as it goes through various operating states and make decisions to steer it back to the normal state. As the time went by, many things have changed in the area of power systems: introduction of the electricity markets to accommodate competitive trading, the growth of the power system infrastructure to meet demands for renewable resources, EMS technology to improve computations, communications and visualization. Hence, almost 50 years after the initial proposals for the EMS solution as we know it today...

This paper presents new software framework aimed at automating the analysis of power system transients. The transients of interest are those caused by faults and power quality disturbances. Various intelligent electronic devices can record these transients so that their impacts on the equipment and system operation can be studied. Today, such analysis is done manually and requires significant effort and expertise. Innovative approaches and tools are required to attain greater efficiency. The paper presents an approach where the expertise in analysis and simulation area is embedded in the software modules that can be executed automatically. The paper also shows that parallel use of analysis and simulation techniques lead to enhanced methods and improved results.

The paper presents an approach to locate a fault in a transmission network based on waveform matching. Matching during-fault recorded phasor with the during-fault simulated phasor is used to determine the fault location. The search process to find the best waveform match is actually an optimization problem. The genetic algorithm (GA) is introduced to find the optimal solution. The proposed approach is suitable for the situations where only the data recorded sparsely is available. Under such circumstances, it can offer more accurate results than other known techniques.

To help make the power system more reliable huge amount of data generated from different Intelligent Electronic Devices (IEDs) located in substation of power system should be collected, analysed and displayed. Easy way of accessing and viewing recorded data or information obtained through automated analysis is commonly lacking in the existing power systems. Nowadays data and related information presentation is one of the most important requirements in power engineering. Many users find that their work is more efficient when using versatile data/information presentation software. The emphasis in this paper is on implementing user-friendly, device independent data/information presentation with ability for remote access too.

The paper focuses on deployment challenges for automated substation data analysis solutions. Through examples from recent deployment projects, the paper discusses the fact that both the utilities and suppliers are dealing with a set of requirements defined as a compromise between the needs of variety of in-house stakeholders. These requirements are prone to changes and that itself is one of the biggest challenges. In addition, the deployment is almost always faced with unexpected challenges from the production environment itself. The paper illustrates a gradual step-by-step approach from a solution demonstration to the production deployment. The first part focuses on the solution that analyzes digital fault recorder and digital protective relay data. In-house testing with both simulated data and with the data obtained from the field is discussed. The second part of the paper discuses implementation and deployment of a new circuit breaker recorder aimed at on-line monitoring circuit breaker operations.

More and more intelligent electronic devices (IEDs) are being installed and utilized in power system substations. Majority of these new devices come with event recording feature and some even provide fault location calculation. In case of power system faults, protection and fault analysis engineers are often presented with event recording coming from various substations and also from multiple devices. There are several challenges in processing these files efficiently in order to perform analysis and make decision based on the event data. This paper focuses on the fault location calculation based on event recordings from IEDs such as digital fault recorders or protective relays. The paper addresses requirements and obstacles when the event data is to be processed automatically in order to enable automated fault location calculation. On the other side, the paper shows examples where combining automated and manual data analytics tools create additional benefits through the use of new fault location calculation tool.

Automation of fault analysis is a desirable future application due to "explosion" of on-line substation data collected during disturbances. Analyzing this data manually is just not feasible; automation of the analysis is necessary. This paper focuses on three options for implementation of automated fault analysis based on: a) uses of individual Intelligent Electronic Devices such as Digital Fault Recorders (DFRs), Digital Protective Relays (DPRs), Sequence of Events Recorders(SERs), etc, b) integrated substation automation systems with all Intelligent Electronic Devices (IEDs) interconnected, and c) integrated enterprise monitoring and control system including Supervisory Control and Data Acquisition (SCADA) Remote terminal units (RTUs) combined with other substation IEDs. For each of the approaches, implementation requirements are discussed and possible benefits are outlined.

The aim of this paper is to introduce two important issues when selecting new Intelligent Electronic Devices (IEDs) as a part of the substation automation system implementation, namely the evaluation means and new applications. For the evaluation purposes, several digital simulator applications are discussed together with the benefits obtained by utilizing the simulators. The evaluation of the IEDs prior to the purchase as well as in the field is described. Regarding implementation of new functions, the importance of the concept of data integration and information exchange is elaborated. It is pointed out that most of the new applications require unconventional use of data and information to yield specific benefits, which will justify the use of substation automation systems. The scope of the paper is restricted to discussion of various methodologies and generic tools and it is not aimed at discussing specific commercial products or services. In conclusion, the paper points out that the use of advanced IEDs and substation automation systems requires significantly different approach in evaluating and implementing the new solutions. Besides the need to better understand functionalities of new IEDs and their performance characteristics, the designers of the future substation automation systems need to understand what are the new benefits that may be obtained by introducing non-traditional functionalities that are made possible through data integration and related processing at the substation level. The new functions may require different approach to database and user interface solutions and are expected to provide more automated means of handling the data and making related control decisions. This paper addresses both issues: evaluation of IEDs and new functions. After a background section, which talks about the latest IED and substation automation standards and related business advantages, the paper concentrates on a discussion of digital simulators that may be used for evaluation of new IEDs. After that, a discussion of new applications aimed at automating the monitoring and control tasks is provided. The paper ends with conclusions and a list of references.

This paper introduces a new paradigm for data integration where the substation field data recorded by monitoring and protection Intelligent Electronic Devices (IEDs) is used to supplement Remote Terminal Unit (RTU) data for Supervisory Control and Data Acquisition (SCADA) system, which improves SCADA and other applications. This data integration paradigm allows very detailed monitoring of the power system and subsequently a more comprehensive decision making opportunities for the control applications. The data interfacing between the substation IEDs and EMS SCADA database to allow for such integration is elaborated on indicating various issues in using present IEC standards 61850 and 61970 to accomplish the required data interfacing. The paper ends with a discussion of the benefits of such an approach.

This paper describes a new solution for automated analysis of fault records captured by digital fault recorders (DFRs) and automated dissemination of event reports. The solution is based on the client/server architecture consisting of modules installed in substations, central office and user desktops. Substation-based modules perform DFR file conversion, signal processing, event analysis and fault location. Main part of the analysis is centered on the expert system whose knowledge base has been tested in a prototype system over the last five years. Server-based modules provide centralized DFR data archiving and event reports dissemination. Main software modules on the server are the database, report parser and Web site. The installation of the system in Reliant Energy HL&P's substations is underway. Initial field-testing shows that functional requirements are completely met.

Automated monitoring of power systems has become an imperative due to two major developments that characterize the 21 st century electricity grid: a) large scale deployment of intelligent electronic devices (IEDs) has created huge amount of data recorder either continuously or at the time when IED recording is triggered by an event such as disturbance or fault, and b) the power system loading has increased to the point where it operates close to the limits, which requires much better monitoring capability than what is available today to make sure such operation does not create undesirable consequences such as cascading failures. Fully aware of the challenges the North American Electric Reliability Corporation (NERC) has developed standards for event monitoring and reporting, which will assure the bulk electricity system is reliable, adequate and secure. To fulfil NERC and/or internal requirements for improved monitoring utilities have started deploying advance solutions that enable automated collection of field data, extraction of information and distribution of monitoring reports so that the utility staff can respond to the events expeditiously. The deployment exaples illustrated in this paper are aimed at demonstrating various deployment strategies that are possible with such solutions: substation, distributed and centralized-based processing. The substation processing requires installation of a PC that serves as the integration hub which collects recorded files from all substation IEDs, converts data to information and creates event reports that are sent to the groups that need them. The distributed solution retrieves IED records and passes them to a location such as protection office, operator control room or maintenance canter where further processing is done. The centralized solution collects all the data to a centralized database, extracts information and sends it to the users per request. To illustrate the above concepts several hardware and software solutions are developed and deployed in the field: circuit breaker recorder, automated analysis of circuit breaker recorder (CBR) data, automated analysis of digital protective relay (DPR) data, automated analysis of digital fault recorded (DFR) data, automated integration of substation IED data, automated handling of user interfaces. All the solutions are implemented using advanced hardware and software concepts that allow the recorded data to be synchronized and time stamped utilizing receivers for Global Position System (GPS) of satellites. Time stamped data are communicated through variety of modern communication media such as wireless, optical fibre and high speed coaxial cable links. Handling of software applications is through advanced JAVA programming, and user interfaces deploy latest advancements in the web browsers and graphical user interfaces. Practical issues such as cyber security, implementation steps and personnel acceptance are addressed as well.

The intent of this paper assimilates the issues of automatic generation control (AGC) of a two-area power system entailing five numbers of renewable as well as conventional sources such as thermal unit, hydro unit, wind unit, diesel unit, and photovoltaic (PV) unit. To make the proposed model more realistic, some non-linearities like boiler dynamics, governor dead band (GDB), and generation rate limit (GRC) are inducted into their concerned sources. The frequency stability of the system is enhanced by assuaging the transient indices like undershoot, overshoot, rise time, and settling time by employing two degrees of freedom (2-DOF) based fractional order (FO) cascaded controller incorporating with derivative filter (N) named 2-DOF-FOPIDN-FOPDN controller. The proposed controller along with 2-DOF-PIDN-PDN, and PID controllers are designed by endorsing selfish herd optimization technique (SHOT). The performance of the proposed controller is corroborated by comparing the performance exhibited by 2-DOF-PIDN-PDN, and PID controllers. Besides this, the know-how of the recommended controller is evaluated and investigated against solar power variation, load perturbation, and system's parameter deviation which confers the robustness of the controller is conceived.

Inter-area oscillations are inherent to power systems which can be caused due to oscillation of two coherent groups of generators against each other with low or negative damping. Poorly damped oscillations can pose various problems such as limiting transfer capabilities and in more severe cases can lead to uncontrolled islanding causing system blackout. In this paper, for damping inter-area oscillation a new method based on the wide area measurement system (WAMS) and using generation rescheduling (GR) is proposed. The proposed algorithm consists of three tasks; identification of inter-area mode, determination the most effective generators for rescheduling and enhancing damping of inter-area mode by GR. In this approach, first by means of Independent Component Analysis (ICA) and modified Random Decrement (RD) techniques and using on-line power and rotor angle oscillation data provided by WAMS, the frequency and damping of the inter-area mode is identified. In the case of low damping of oscillation, by using mode shape of the inter area mode, generation rescheduling is applied for improvement of damping. In this paper, a non-model based method is adopted for estimating mode shape from the measured data like generator rotor speeds. The proposed approach is applied on a two area small system and IEEE 39-bus test system and the results demonstrate effectiveness of the method for enhancing oscillation damping.

This paper presents a study of the impact of loads on power flow in power system. It deals with the impact of both the voltage nodes and the transmission of active and reactive power in lines, and therefore the loss of active and reactive power in the system. Flexible Alternating Current Transmission System (FACTS) devices are found to be encouraging in improving voltage stability limit in power systems. This paper investigates the application of FACTS devices (Static Var Compensator, SVC) on a 9-bus multimachine power system, it deal with the line losses and improving voltage stability limit. Amount of increased reactive power generation and line losses are taken as indicators of stressed conditions of a power system. The use of SVC is identified by PowerApps and ETAP software packages. Both software are used for IEEE 9 bus test system and the results obtained are presented and interpreted.

An optimal load shedding strategy for power systems with optimum location and quantity of load to be shed is presented in this paper. The problem of load shedding for avoiding the existence of voltage instability in power systems is taken as a remedial action during emergency state in transmission and distribution sector.Optimum location of loads to be shed is found together with their optimum required quantity. L-Indicator index is in used for this purpose with a modified new technique. Applications to be standard 6 bus Ward-Hale test system and IEEE -14 bus system are presented to validate the applicability of the proposed technique to any system of any size.

This work presents the experimental evaluation for a new scheme of Optimal Vector Selection (OVS) in Direct Power Control (DPC) for a three-phase rectifier without the use of switch selection tables. The OVS is physically implemented using a software configurable test rig (Platform III). Additional states were added to the standard seven space vectors obtained with a three-phase inverter bridge using Space Vector Modulation (SVM) in order to reduce the hysteresis band of the power controller. Normal operation, model parameter fit, regenerative behavior and comparisons between two different sets of vectors are analyzed.

The liberalization of the electricity market and the growing contribution of renewable resources RES induce a large variety of scenarios that may lead power systems close to their operation limits. On-line Dynamic Security Assessment (DSA) of the grids is thus required, in order to provide operators with a clear insight of the current network state. The on-line application of DSA to a realistic network needs adequate methods to screen the large amount of contingencies to be examined by DSA tools. This paper proposes some practical heuristic indices for Transient Stability contingency pre-filtering and ranking in an on-line DSA session. The application of the indices to an IEEE test system and to a large realistic power system gives promising results. grid components. However it is still useful to maintain a phase of contingency pre-filtering to avoid wasting a large amount of time for the security assessment of very stable contingencies. This time may be better used to test preventi...