Francisco R. A. C. Baracho

Bio: Francisco R. A. C. Baracho is an academic researcher from Universidade Federal de Ouro Preto. The author has contributed to research in topics: Control reconfiguration & Information technology. The author has an hindex of 4, co-authored 19 publications receiving 49 citations. Previous affiliations of Francisco R. A. C. Baracho include Universidade Federal de Minas Gerais.

A theoretical and practical approach for underexcitation protection and control studies of large hydrogenerators in a real-time environment

Abstract: Protection devices and excitation systems are essential components for the protection and control of synchronous generators. The installation and settings of these devices are performed during commissioning and require experience since a failure can cause damage to the generator and the corresponding grid. A test bed implemented in a real-time digital simulator is presented in this paper as an alternative for the training and learning process that involves the knowledge of an effective coordination between such protection and control systems. A complete generation system is implemented in a real-time digital simulator, including an excitation system model with its limiters. These limiters are coordinated with the protection functions implemented in a physical relay. The contributions of this work are: the demonstration of the importance of this type of study (i.e., real time simulations results through hardware-in-the-loop tests); the consolidation of the impedance (R-X) and admittance (G-B) planes as the more accurate ones to analyze the coordination between the ANSI 40 function and the underexcitation limiter; and the presentation of a study focused on large hydrogenerators (including novel settings for the 40 protection). This research also paves the way for improvements on similar studies focusing on turbogenerators.

A Theoretical and Practical Approach for Underexcitation Protection and Control Studies of Hydrogenerators in a Real-Time Environment

Abstract: The installation and settings of protection devices and excitation control systems require experience since a failure can cause damage to the synchronous generator and negative impact on the power grid. A test bed implemented in a real-time digital simulator (RTDS) is presented in this paper as an alternative for the training and learning process that involves the knowledge of an effective coordination between such protection and control systems of synchronous generators. A complete generation system is implemented in a RTDS, including an excitation system model with its limiters. These limiters are coordinated with the protection functions implemented in a physical relay. The contributions of this work are the demonstration of the importance of this type of study (i.e., real-time simulations results through hardware-in-the-loop tests), the consolidation of the impedance (R-X) and admittance (G-B) planes as the more appropriate ones to analyze the coordination between the ANSI 40 function and the underexcitation limiter, and the presentation of a study focused on hydrogenerators (including novel settings for the ANSI 40 protection).

Knowledge Management in Electricity Generation Strategic Decisions: The Dawn of the Renewable Age

Abstract: The world has the challenge of expanding electricity production meeting demand and ensuring energy security for the support and development of society. Given data and information on energy sources are available on a large scale, there is an opportunity to develop a tool that enhances and contributes to decision making in the energy sector. With this in mind, this article brings together the use of technology, finance, information and intangibles with the objective of enhancing the decision-making process for the implementation and optimization of the fuel input mix for the power industry. The results presented in the article are obtained by means of technical, economic and information management analysis that constitute the theoretical basis of intangibles, all of them supported by information technology. This article presents both a new methodology and a new software to obtain optimum investment decisions in the power industry, focusing on power production. The development and validation of the methodology and software are described. The best energy investment to be made is based on the extraction and evaluation of the knowledge of the energy sector specialist in a logical and mathematical way. The results of the research present a decision-making process based on more formal and less personal criteria, guaranteeing greater neutrality and convergence in the decision-making process.

A Test-Bed for Researching the Interactions of Underexcitation and Overexcitation Limiters of Synchronous Generators with Protection Functions

Abstract: A test-bed implemented in a real-time digital simulation environment is presented in this article to perform coordination studies between protection functions and excitation limiters of automatic voltage regulators of synchronous generators. A hardware-in-the-loop simulation is implemented in laboratory to test and evaluate several protection schemes during underexcited and overexcited events. The interactions among the underexcitation and overexcitation limiters (UEL and OEL) with these protection functions are investigated, and the best settings for their coordination are proposed. This article increases the scope of [1] and [2] by including the interactions among the protection functions ANSI 24 (V/Hz), ANSI 59 (overvoltage), and ANSI 81 (underfrequency and overfrequency) with the OEL, and the interactions among the protection functions ANSI 21 (distance) and ANSI 27 (undervoltage) with the UEL in addition to the coordination between the protection function ANSI 40 (loss of excitation) and the UEL. Thus, the appropriate settings for these protection and controls are proposed for the excitation system developed. The main results are presented and discussed.

Optimal Reconfiguration of Power Distribution Network for Stability Voltage and Power Quality Improvements

Abstract: This work presents a network reconfiguration method aimed at improving, simultaneously, stability voltage and harmonic distortion in a distribution system where non-linear loads are present. In such reconfiguration process, the meta-heuristic Particle Swarm Optimization, which uses a local search, is deployed to evaluate the stability voltage and harmonic distortion using the maximum loading supported by the network and the Total Harmonic Distortion (THD) in a multi-objective cost function. The methodology is applied to the IEEE 33-bus distribution network. The results prove the efficiency of the developed method to find the best topologies of the electrical network in relation to the maximum loading supported by the network and the level of harmonic distortion.

Distribution Feeder Reconfiguration for Service Restoration and Load Balancing

Abstract: This paper describes two feeder reconfiguration algorithms for the purpose of service restoration and load balancing in a real-time operation environment. The developed methodologies combine optimization techniques with heuristic rules and fuzzy logic for efficiency and robust performance. Many of practical operating concerns of feeder reconfiguration and the coordination with other distribution automation applications are also addressed. The developed algorithms have been implemented as 8 production grade software. Test results on PG&E distribution feeders show that the performance is efficient and robust.

An Analysis of the Renewable Energy Technology Selection in the Southern Region of Bangladesh Using a Hybrid Multi-Criteria Decision Making (MCDM) Method

Abstract: Bangladesh is a country of small char lands and islands. Most of these are out of national grid coverage. Therefore, renewable energy technology is the only solution to electrify. However, proper investigation and research is needed to select the most suitable renewable energy technology. In this study focus is given on the southern region of the country to select the best renewable technology. Based on the current available technology and potentiality of the renewable energy resources in the country five types of renewable energy technology are selected for the evaluation. These are solar, wind, biomass to electricity, biogas to electricity and solar-wind-battery hybrid energy system. To evaluate the best renewable energy technology Multiple-criteria decision analysis (MCDM) method is used where anintegrated Entropy-EDAS model is proposed to identify the best renewable energy technology in the study area. At first, the key criteria and sub-criteria were selected to analysis five (5) types of renewable energy technologies. These criteria were categorised as economic, technical, environmental, and socio-political.Additionally, 12 sub-criteria were selected under the umbrella of four main criteria. Then, the Shannon’s Entropy method was deployed to find the weights of the criteria and sub-criteria. Finally, a new MCDM method named Evaluation based on Distance from Average Solution (EDAS) was applied to select the best renewable energy technology in the study area. The results revealed that the Solar-Wind-Battery hybrid energy system is the best option. The outcome of this study and the decision model might be applicable to other isolated areas in the country, particularly in the southern region of Bangladesh.

Technical - Economic Study for the Implementation of Solar Energy in the Presence of Biomass and Micro Hydraulic Generation, for Sectors that do not Have Electricity Supply in the Province of Bolívar-Ecuador

Abstract: This article presents a study based on successful experiences in Ecuador and originating a systematic study of the use of renewable energy for the Province of Bolivar in Ecuador. The process that follows is the analysis of contribution by contribution of renewable energy to a system proposed as a hybrid, for this a general scheme is carried out, we accompany a flow chart, the fundamental equations that govern the system, it is modeled, we perform simulations and we establish graphs of system behavior under different conditions. The energy sources considered are the photovoltaic-biomass-hydraulic since they are the potentially exploitable in the locality. The above is compared with data from national locations where previous studies were carried out and which are of reference for this project.

A Theoretical and Practical Approach for Underexcitation Protection and Control Studies of Hydrogenerators in a Real-Time Environment

Abstract: The installation and settings of protection devices and excitation control systems require experience since a failure can cause damage to the synchronous generator and negative impact on the power grid. A test bed implemented in a real-time digital simulator (RTDS) is presented in this paper as an alternative for the training and learning process that involves the knowledge of an effective coordination between such protection and control systems of synchronous generators. A complete generation system is implemented in a RTDS, including an excitation system model with its limiters. These limiters are coordinated with the protection functions implemented in a physical relay. The contributions of this work are the demonstration of the importance of this type of study (i.e., real-time simulations results through hardware-in-the-loop tests), the consolidation of the impedance (R-X) and admittance (G-B) planes as the more appropriate ones to analyze the coordination between the ANSI 40 function and the underexcitation limiter, and the presentation of a study focused on hydrogenerators (including novel settings for the ANSI 40 protection).

Knowledge Management in Electricity Generation Strategic Decisions: The Dawn of the Renewable Age

Abstract: The world has the challenge of expanding electricity production meeting demand and ensuring energy security for the support and development of society. Given data and information on energy sources are available on a large scale, there is an opportunity to develop a tool that enhances and contributes to decision making in the energy sector. With this in mind, this article brings together the use of technology, finance, information and intangibles with the objective of enhancing the decision-making process for the implementation and optimization of the fuel input mix for the power industry. The results presented in the article are obtained by means of technical, economic and information management analysis that constitute the theoretical basis of intangibles, all of them supported by information technology. This article presents both a new methodology and a new software to obtain optimum investment decisions in the power industry, focusing on power production. The development and validation of the methodology and software are described. The best energy investment to be made is based on the extraction and evaluation of the knowledge of the energy sector specialist in a logical and mathematical way. The results of the research present a decision-making process based on more formal and less personal criteria, guaranteeing greater neutrality and convergence in the decision-making process.