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In this work, it is proposed to calculate the sensitivity of parameters, based on analytical calculation, of repowered system between two electric generators, an induction generator and a synchronous generator, connected to a common bus in permanent regime, subject to a non-linear load. It is proposed a repowered system with simulated data where, based on percentage variations in the base values of...
This paper presents a method of the adequacy of voltage transgression in a real power distribution network. This method aims to adjust the voltage levels through the optimization of the insertion position of Photovoltaic (PV) Distributed Generation (DG) in the network. The real feeder was simulated using Open Distribution System Simulator (OpenDSS) software. The optimization used a deterministic method...
This paper presents the computer simulation of a switched reluctance machine (SRM) operating as a generator proposing an alternative for the representation of the inductances of the machine coils and their respective rates of variation. The simulation results show the reliability of the proposed model, especially in comparison with other models of machine inductance representation. The validation...
The presence of gaps in time series makes the data analysis process difficult. Although there are several methods for filling such gaps, they do not present satisfactory results as the gap widens. The proposal of this paper is to present a new methodology that uses techniques of extraction of characteristics and identification of systems to fill the missing data. The proposed methodology was applied...
This article presents a way to solve Resource-Constrained Project Scheduling Problem with genetic algorithm and demonstrates the high relevance of metaheuristics for solution this type problem. Also shows various benchmarks with others heuristics. The benchmark performed compares directly to a relatively new heuristic and to several other works performed. The genetic algorithm together with the approach...
This paper proposes a development's prediction model based on Artificial Neural Network. The methodology proposed consists in: i) countries selection; ii) selection and obtainment of indicators referring to the selected countries; iii) proposal prediction model; iv) Artificial Neural Network training and validation. The results indicated predicted values close to the real values of the Brazilian indicators...
This work proposes different methods to calculate the sensitivity of system parameters based on graphic analysis. From percentages variations in base values of the parameters, one-at-a-time measures are taken to the construction of a graph that expresses the impact on the output caused by variations in the inputs. Two case studies are proposed, with simulated and experimental data, in which the proposed...
In this paper the switched reluctance generator (SRG) is explored considering the improvement of its efficiency. This machine generates a DC power that is directly related to input driving parameters. Simulation results are presented bringing a case study of parametric regression to track the best efficiency for any input parameters: excitation voltage and turn off angle. A method known as parametric...
This paper presents a speed control for a DC motor. Despite the unknown parameters of the plant to be controlled, these parameters are found using a system identification method. The methodology implemented in this study is known as parametric regression and is based on an optimization technique. This optimization, through its fitness function, allows to find the system characteristics in order to...
The approach of this paper it is about voltage conformity delivered to the final customer, on electricity distribution networks. Have obtained physical and electrical characteristics information from the network coming from the database of the electricity company. The study presents the process of voltages estimation in primary and secondary circuits wich estimation of indicators of voltage violation...
The purpose of this work is to find the values of the electric parameters of synchronous and induction machines in order to validate the electrical interactions between an induction generator and a synchronous generator. The two generators will be connected in two ways: i) isolated to the common bus and ii) jointly connected to the common bus in permanent regime, subject to non-linear load. The results...
Considering the actual environmental appeal due to excessive consumption of fossil fuels, is relevant the research and development of green power sources in order to conserve the natural resources. Wind energy has become a target of researches and highlights a clean energy scenario. Electrical machines have its reversibility and, operating as generators, can be useful for wind energy aaplications...
This paper presents experimental and simulation results for an induction motor operating with PI (proportional and integral) and Fuzzy speed controllers. This results aim to stablish a comparative analysis between both controllers regarding steady state and transient speed behaviour, just like perfomance under disturbances. To collect the results tests were made in a workbench integrated by several...
This paper proposes speed to control a the direct current motor (DC motor) containing a PWM signal as input. Through tuning and motor data, a real system can be modeled. Tests are performed in real system to develop a simulation environment. Thus, it is possible to perform PID control by adjusting the gains by the classical Ziegler-Nichols method and then, to compare the results using deterministic...
This paper presents a study about the use of a proportional-integral (PI) controller in the cascade configuration. A sensitivity study about the controllers parameters was done and, after that, they were obtained through optimization methods employing deterministic and heuristic strategies. This methods were applied on a simulation model, in order to verify which one provides better control results.
This paper reports on a PID controller for speed control of a DC motor. The controller parameters were obtained through optimization methods employing heuristic and deterministic strategies. This methods were applied on a simulation model in order to verify which one provides better control results.
This paper reports on a Switched Reluctance Machine (SRM) operating as generator excited through external power source. This device provides DC voltage output through its power converter. Parameters such as rotor speed, excitation voltage and firing angles interferes directly on the output voltage. Thus, many strategies have been studied and developed by scientific community in order to control the...
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