No abstract

In this study, a hydrokinetic turbine is designed for the high-altitude regions where local electricity network lines are difficult to reach. If there was a stream flow around, electricity production could be possible and necessary because of environmental reasons. The performance of the hydrokinetic turbine was investigated experimentally and numerically. The numerical analyses of the turbine system were performed via MATLAB/Simulink version R2014a. Except power-based performance characteristics, efficiency of the system in terms of installation and necessary investment costs were also investigated. It is calculated that the system to be established on a river with a water flow rate of 30 m3/h will meet the investment cost in approximately 8 years.

With two different regions of a Load Frequency control of power systems using fuzzy logic-based controller are examined. With a load of any change in the frequency of the power system investigated how affected. Then Fuzzy Logic Controller (FLC) changes, such as what is observed in using the system. The system has two different control area power system small signal model in Matlab / Simulink computer simulation program was created. FLC in the control and Integral Controller has been using the system. This produces two different results are compared with the controller. Keywords-Fuzzy Logic Controller (FLC), multi-zone power system (MZPS).

In this study, a dynamic system has been modeled to efficiently use a photovoltaic generation and control system (PVGCS) for driving of a medium power off-grid electric machine. The measures have been taken to respond to three different disturbing factors in this system. First, the photovoltaic panels selected for energy generation have a variable solar radiation effect. Second, the DC motor load at the system output is assumed to have a variable torque. Third, a variable reference voltage, which is determined even in the case of time-varying energy generation and consumption of the system, is followed with minimum error. For this purpose, a push-pull converter has been chosen as a highly flexible structure since it is predicted that it can provide stable and effective variable DC voltage at increasing and decreasing level required for DC motor. The control of the DC voltage at different levels to be provided by the push-pull converter is performed by PI, fuzzy logic, fuzzy-tuned PI, 2-DOF PI, and fractional PID logic whose coefficients are selected by appropriate methods, respectively. The system efficiency and stability under the influence of these five different advanced controllers are compared. In the case of two disturbing factors affecting the system, the difference values (errors) of the voltage generated by each selected controller with the reference voltage are determined comparatively. The studies were carried out by using dynamic system modeling in MATLAB-SIMULINK software. In addition, the results of this study proved which type of controllers is more successful in controlling systems with the second order and more instability factors and which of them responds to sudden changes in errors more quickly.

DC-DC converters are widely used in electrical machinery driver circuits. Classic controllers and fuzzy logic controllers, DC converters operating range setting switches provide control of electrical machines drives. In this study, which is one of the Cúk converter DC converters MATLAB / Simulink model was prepared, at the output of a DC Motor Dynamic Model, Proportional Integral, Proportional Integral Derivative and Fuzzy Logic Controllers to be controlled by a speed and a reference was provided and compared with the performances of these controllers.