Axial flux machines are used frequently in wind energy applications due to their high power densities and efficiencies. However, the parametrical dependencies of those generators affect the generated power and efficiencies. For instance, turbine blade structures dimensions, change dramatically the speed and torque characteristics. Hence, this study includes a pursuit of optimization and the related design parameters for an axial generator in terms of its off grid operations. The analytical design relations and simulated data have shown that the geometric dimensions and morphology of the machine can be analyzed effectively under the finite element method and the optimization of the machine can be provided with a good accuracy by applying the response surface optimization. Cogging torque and power density formulated aim function gives a good optimization for the design. According to this approach, the general performance of the machine is maximized and the cogging torque and weight are kept to be decreased. Design variables are optimized by considering the generator size. Consequently, an optimal 4.8% increase in weight can yield to a 27.4% power enhancement in the machine.

Linear generators are electric machines which generate electrical energy from linear movement. Since these machines can lift gear wheel or power train, they have begun to be used widely nowadays. Since their working areas differ according to speed and power characteristic, this study contains design and optimization of tubular linear generator for free piston practices. The design performed response surface optimization through design variables was acquired as a result of sizing via interface. The association between the determined design variables and the sizes of generator output was examined. In addition, these sizes were used for objective functions of increasing efficiency, decreasing overall volume and increasing general performance and their optimum values were found by using Multi-Objective Genetic Algorithm. Initial and optimum design data were compared with Ansys Maxwell 2D. With overall performance increase, 22,78% decrease was seen in total mass, while 11,7% decrease was seen in cost. In addition, prototype linear generator was made in line with initial geometry data and it was applied with crank slider mechanism.

This study explores the use of electrostatic cleaning to remove dust from the surface of photovoltaic solar panels. First of all, existing systems used for dust removal from solar panels were evaluated. Then, the effects of dust on the panel were investigated for Şanlıurfa province in Turkey. In addition, the elemental content of the powder was analyzed. A new device for electrostatic cleaning has been designed and implemented. The cleaning performance of this device has been tested considering the electrode designs. The electric field value was determined by analytical and numerical methods in the conventional model (parallel electrode) model. Electric field distribution was investigated using Ansys Maxwell simulation software. The printed circuit boards of the proposed model and the conventional model were produced. The traditional model with positive and negative waveform is widely used in electrostatic cleaner studies. Dust removal efficiencies and electrical losses for different frequency and voltage values were compared for both cards. It has been shown that the proposed model can perform cleaning with high efficiency despite similar loss variation.

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Free piston generators are of interest due to their efficiency, compact construction, and multiple options for combustion. Much of the research into this type of generator has been facilitated by highly-developed internal combustion engine technology. This study was concerned with the design and application of tubular generator. The design model was developed using the matrix laboratory graphical user interface programming tool, and the designed interface was of the dynamic type. The sizing of the generator was determined in accordance with the main parameters specified via the interface. In addition, as a benefit of using sizing data, the automatic geometry was formed and analyzed using ANSYS Maxwell software. The magnets and the dynamic part of the tubular-structured generator were shaped polygonally. Numerical analyses were made by adopting the finite element method in the software and construction of the prototype model was based on the results from these findings. The generator was excited by use of the crank rod mechanism to imitate the conditions of a functioning free piston mechanism. Current and voltage values were obtained at mechanical frequencies of 10 Hz and 20 Hz, and this data was subsequently analyzed.Global code translation was given in attachment in order to allow communication between the ANSYS Maxwell and MATLAB GUI software.