Estimating Cell Capacity for Multi-Cell Electrical Energy System

A Multi-Cell Electrical Energy System is a set of batteries that are connected in series. The series batteries provide the required voltage necessary for the contraption. After using the energy that is provided by the batteries, some cells within the system tend to have a lower voltage than the other cells. Also, other factors, such as the number of times a battery has been charged or discharged, how long it has been within the system and many other factors, result in some cells having a lesser capacity compared to the other cells within the system. The outcome is that it lowers the required capacity that the electrical energy system is required to provide. By having an unknown cell capacity within the system, it is unknown how much of a charge can be provided to the system so that the cells are not overcharged or undercharged. Therefore, it is necessary to know the cells capacity within the system. Hence, if we were dealing with a single cell, the capacity could be obtained by a full charge and discharge of the cell. In a series system that contains multiple cells a full charging or discharging cannot happen as it might result in deteriorating the structure of some cells within the system. Hence, to find the capacity of a single cell within an electrical energy system it is required to obtain a method that can estimate the value of each cell within the electrical energy system. To approach this method an electrical energy system is required. The electrical energy system consists of rechargeable non-equal capacity batteries to provide the required energy to the system, a battery management system (BMS) board to monitor the cells voltages, an Arduino board that provides the required communication to BMS board, and the PC, and a software that is able to deliver the required data obtained from the Arduino board to the PC. The outcome, estimating the capacity of a cell within a multi-cell system, can be used in many battery related technologies to obtain unknown capacities of different cells; such as the EcoEagle that partially receives its power from the electrical energy system. This thesis was conducted as the theory behind the EcoEagles Electrical Energy System

Validity and significance of assessing the competence of employees in the electrical energy system

Currently, the energy sector is growing rapidly. But the electric power industry is one of the most responsible areas. Through this article, mandatory forms of work with employees in the field of electric power and the qualification and principle of work of employees in safe work at power plants are studied and applied

Applying a Revised Approach of Fuzzy Cognitive Maps on a Hybrid Electrical Energy System

Complex systems modeling is a rapidly developing research field which incorporates various scientific sectors from bio medicine and energy to economic and social sciences. However, as the systems’ complexity increases pure mathematical modeling techniques prove to be a rather laborious task which demands wasting many resources and in many occasions, could not lead to the desired system response. This realization led researchers turn their attention into the field of computational intelligence; Neural Networks and Fuzzy Logic etc. In this way scientists were able to provide a model of a system which is strongly characterized by fuzziness and uncertainties. Fuzzy Cognitive Maps (FCM) in another methodology which lies in the field of computational intelligence. FCM came as a combination of Neural Networks and Fuzzy Logic and were first introduced by B. Kosko in 1986. All these years they have been applied on a variety of systems such as social, psychological, medical, agricultural, marketing, business management, energy, advertising etc, both for systems modeling and decision-making support systems, with very promising results. Classical FCM approach uses the experts’ knowledge in order to create the initial knowledge base of each system. Based on the experts’ knowledge, the interrelations among the system variables are determined and the system response is defined. Through years, improvements have been made and learning algorithms were embodied in the initial approach. Learning algorithms used data information and history to update the weights (the interconnections) among concepts (variables), contributed to the optimization of FCMs and reached more efficient systems’ response. However, all these decades, researchers have mentioned some weak points as well. In the last years substantial research has been made in order to overcome some of the well-known limitations of the FCM methodology. This paper will apply a revised approach of the Fuzzy Cognitive Maps method on a techno-economic study of an autonomous hybrid system photovoltaic and geothermal energy Specifically, the FCM model of this system includes twenty-five concepts and three of them are considered as outputs, the total system efficiency, the total energy production and the total system cost. The aim of the study is to provide maximum performance with the minimum total cost. To this end results for both the classic and revised approach of the FCM method are provided and discussed. Computational Intelligence and especially Fuzzy Cognitive Maps are a very promising field in modeling complex systems. The latest approaches of the method show that FCM can open new paths towards higher efficiency, more accurate models and effective decision-making results

Applying a Revised Approach of Fuzzy Cognitive Maps on a Hybrid Electrical Energy System

Complex systems modeling is a rapidly developing research field which incorporates various scientific sectors from bio medicine and energy to economic and social sciences. However, as the systems’ complexity increases pure mathematical modeling techniques prove to be a rather laborious task which demands wasting many resources and in many occasions, could not lead to the desired system response. This realization led researchers turn their attention into the field of computational intelligence; Neural Networks and Fuzzy Logic etc. In this way scientists were able to provide a model of a system which is strongly characterized by fuzziness and uncertainties. Fuzzy Cognitive Maps (FCM) in another methodology which lies in the field of computational intelligence. FCM came as a combination of Neural Networks and Fuzzy Logic and were first introduced by B. Kosko in 1986. All these years they have been applied on a variety of systems such as social, psychological, medical, agricultural, marketing, business management, energy, advertising etc, both for systems modeling and decision-making support systems, with very promising results. Classical FCM approach uses the experts’ knowledge in order to create the initial knowledge base of each system. Based on the experts’ knowledge, the interrelations among the system variables are determined and the system response is defined. Through years, improvements have been made and learning algorithms were embodied in the initial approach. Learning algorithms used data information and history to update the weights (the interconnections) among concepts (variables), contributed to the optimization of FCMs and reached more efficient systems’ response. However, all these decades, researchers have mentioned some weak points as well. In the last years substantial research has been made in order to overcome some of the well-known limitations of the FCM methodology. This paper will apply a revised approach of the Fuzzy Cognitive Maps method on a techno-economic study of an autonomous hybrid system photovoltaic and geothermal energy Specifically, the FCM model of this system includes twenty-five concepts and three of them are considered as outputs, the total system efficiency, the total energy production and the total system cost. The aim of the study is to provide maximum performance with the minimum total cost. To this end results for both the classic and revised approach of the FCM method are provided and discussed. Computational Intelligence and especially Fuzzy Cognitive Maps are a very promising field in modeling complex systems. The latest approaches of the method show that FCM can open new paths towards higher efficiency, more accurate models and effective decision-making results

Commissioning of current transformers

Current transformers are the link between the primary and the secondary system and are therefore essential components of the electrical energy system. Their commissioning is an important phase of evaluating their proper functionality. Nowadays, is continuously decreasing. Moreover, it should be considered how the transformers and the protection system can be adequately tested within a reasonable timeframe. This paper discusses how a test plan for commissioning or refurbishing a substation might look

An efficient program for modeling, control and optimization of hybrid renewable-conventional energy systems

-In this paper, a generic and an efficient model for hybrid renewable-conventional electrical energy systems is presented. This simulation model is successfully validated by means of HOMER. Moreover, two control strategies for electrical power dispatch are described. Furthermore, an optimization problem is formulated and solved, using Genetic algorithm technique, for optimizing the size of system components where the overall cost of the system is minimized. Four case studies are investigated. The results show a dependence of the size of the system components on the meteorological characteristics of the area under consideration, which validate the proposed methodology

Flexible power converters for the fault tolerant operation of Micro-Grids

The progressive penetration level of Distributed Generation (DG) is destined to cause deep changes in the existing distribution networks no longer considered as passive terminations of the whole electrical system. A possible solution is the realization of small networks, namely the Micro-Grids, reproducing in themselves the structure of the main production and distribution of the electrical energy system. In order to gain an adequate reliability level of the microgrids the individuation and the management of the faults with the goal of maintaining the micro-grid operation (fault tolerant operation) is quite important. In the present paper flexible power converters and a companion control algorithm for the fault tolerant operation of microgrids are presented. The effectiveness of such an algorithm and of the fault tolerant power converters are verified through computer simulations

CLEAN COAL TECHNOLOGIES IN THE STRATEGIC DEVELOPMENT OF THE ELECTRICAL ENERGY SYSTEM

U članku je prikazan razvoj tehnologija proizvodnje električne energije iz ugljena. Opisane su tehnologije čistog ugljena kojima je moguće smanjiti ili sasvim izbjeći emisije CO2 i ostalih štetnih tvari u atmosferu. Zbog utjecaja na klimatske promjene posebna je pažnja posvećena mogućnostima odvajanja i skladištenja CO2. Procijenjena je ekonomska isplativost takvih postupaka temeljem razvojnih projekata koji se provode u svijetu. Dan je prikaz suvremenih termoelektrana na kameni i smeđi ugljen koje su u fazi razvoja/izgradnje, a koriste tehnologije čistog ugljena. Napravljen je osvrt na Strategiju energetskog razvoja Republike Hrvatske do 2030. godine i utvrđeno da se sigurnost opskrbe električnom energijom u Republici Hrvatskoj može ostvariti samo oslanjanjem na raznorodne izvore primarne energije: plin, ugljen, nuklearnu energiju i obnovljive izvore. Udjele pojedinih energenata u proizvodnji električne energije treba neprekidno preispitivati uzimajući u obzir svjetska kretanja i vlastite razvojne mogućnosti.The article presents the development of technologies for producing electrical energy from coal. Clean coal technologies are described, through which it is possible to reduce or completely eliminate emissions of CO2 and other pollutants into the atmosphere. Due to the impact on climate change, particular attention has been devoted to the possibility of the capture and sequestration of CO2. The profitability of such procedures has been evaluated, based upon development projects being conducted around the world. Modern stone coal-fired and brown coal-fired thermoelectric power plants using clean coal technology in the development/construction phase are presented. A review has been presented of the energy sector development strategy of the Republic of Croatia for the period until the year 2030 and it is has been determined that the security of the electrical energy supply in the Republic of Croatia can only be achieved by relying upon primary energy sources: gas, coal, nuclear energy and renewable sources. The percentage of individual energy sources in the production of electrical energy should be constantly reassessed, taking world trends and the country\u27s developmental potentials into account

CLEAN COAL TECHNOLOGIES IN THE STRATEGIC DEVELOPMENT OF THE ELECTRICAL ENERGY SYSTEM

U članku je prikazan razvoj tehnologija proizvodnje električne energije iz ugljena. Opisane su tehnologije čistog ugljena kojima je moguće smanjiti ili sasvim izbjeći emisije CO2 i ostalih štetnih tvari u atmosferu. Zbog utjecaja na klimatske promjene posebna je pažnja posvećena mogućnostima odvajanja i skladištenja CO2. Procijenjena je ekonomska isplativost takvih postupaka temeljem razvojnih projekata koji se provode u svijetu. Dan je prikaz suvremenih termoelektrana na kameni i smeđi ugljen koje su u fazi razvoja/izgradnje, a koriste tehnologije čistog ugljena. Napravljen je osvrt na Strategiju energetskog razvoja Republike Hrvatske do 2030. godine i utvrđeno da se sigurnost opskrbe električnom energijom u Republici Hrvatskoj može ostvariti samo oslanjanjem na raznorodne izvore primarne energije: plin, ugljen, nuklearnu energiju i obnovljive izvore. Udjele pojedinih energenata u proizvodnji električne energije treba neprekidno preispitivati uzimajući u obzir svjetska kretanja i vlastite razvojne mogućnosti.The article presents the development of technologies for producing electrical energy from coal. Clean coal technologies are described, through which it is possible to reduce or completely eliminate emissions of CO2 and other pollutants into the atmosphere. Due to the impact on climate change, particular attention has been devoted to the possibility of the capture and sequestration of CO2. The profitability of such procedures has been evaluated, based upon development projects being conducted around the world. Modern stone coal-fired and brown coal-fired thermoelectric power plants using clean coal technology in the development/construction phase are presented. A review has been presented of the energy sector development strategy of the Republic of Croatia for the period until the year 2030 and it is has been determined that the security of the electrical energy supply in the Republic of Croatia can only be achieved by relying upon primary energy sources: gas, coal, nuclear energy and renewable sources. The percentage of individual energy sources in the production of electrical energy should be constantly reassessed, taking world trends and the country\u27s developmental potentials into account