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In this paper, a new solar tracking system designed and constructed at Afyon Kocatepe University to maximize the efficiencies of different photovoltaic (PV) panels is proposed. The system is composed of two main parts: first is the mechanical part, whereas the second is the control part. The mechanical part of the system has the ability to move both in vertical and in horizontal axes. Servo engines are selected and used at this part. On the other hand, control part is designed as to be achieved via remote access. The control strategy of the system should easily be altered when desired. This enabled us to test different control algorithms. Moreover, different PV panels produced by different technologies are tested on the system. Electricity generation outputs of PV panels obtained from the tracking system are compared with outputs of fixed ones. Finally comparison results of different control strategies are presented and discussed. V C 2014 AIP Publishing LLC. [http://dx.

The electricity generations of photo voltaic (PV) panels are strongly related with insolation and temperature. The insolation and temperature are not stable, since the electricity generations of the PV panels are not stable. In PV systems, insolation and temperature continuous vary. Therefore, the maximum power point tracking (MPPT) techniques are used to give the highest power to the loads/batteries. The MPPT process is performed with a power electronic circuit and it overcomes the problem of voltage mismatch between the PV panels and the batteries/loads. In this study, a microcontroller is employed to develop battery charge control system for PV panels. The system is composed of a microcontroller (Microchip PIC18F2550), a buck-boost type DC-DC converter, a resistive load, and lead acid battery. In the system, MPPT, charge control, and discharge algorithms are executed by a program embedded within the microcontroller. The program also has ability to perform some data acquisition process and acquired data are sent to the personal computer (PC) through the USB communication port. In addition the system has able to be followed and controlled by the graphical user interface (GUI).

Abstract-Energy consumption is the main cost item in the marble cutting process by using segmented circular sawblade. Therefore, there are many benefits to take measures for reducing the energy consumption. The aim of this study is to reduce electricity consumption in marble cutting process by using control methods. In the study, cutting experiments were performed with a fully computer controlled test rig for three natural rocks (Burdur beige and Usak green marbles and Afyon travertine). The experiments were carried out on two modes (manual and automatic). In the experiments, travel speed is kept fixed in manual mode as usual in industry. In the experiments performed on automatic mode, travel speed is controlled by a controller embedded closed control loop during the cutting process. In addition other machine parameters such as sawblade rotation speed, cutting depth, flowing speed of cooling water are kept fixed in all experiments. In designed control systems, floating and PID controllers are used to control travel speed. Obtained results are showed that, if the travel speed is controlled during cutting process, energy saving can be provided in both of two controllers for all of three rocks.

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