Metin Colak

Power Controller Design for Photovoltaic Generation System under Partially Shaded Insolation Conditions

Partially shaded photovoltaic (PV) modules typically exhibit additional difficulties in tracking maximum power point (MPP), since their power-voltage (P-V) characteristics are complex and may have multiple local maxima. For this reason, conventional techniques fail to track MPP effectively, if the PV array is partially shaded. This paper presents a novel power compensation and control system for PV arrays under complicated non-uniform insolation conditions. The proposed system is based on forward biasing bypass diode of shaded modules by monitoring dynamic resistance and voltage of PV modules. For this purpose, the proposed system is used DC/DC converter equipped with each PV string in PV array. The proposed system can identify which modules are shaded. The effectiveness of the proposed system is investigated and confirmed for complicated partially shaded PV array.

Simulation and Comparative Practical Performance Analysis Of A Stand-Alone PV Power System in Gökçeada

This study simulates and analyzes the practical performance of a 2 kW stand-alone PV power system located in Gokceada/Turkey. System performance was calculated both by simulation and real life measurements. Although the total system efficiency and the performance ratio is simulated 5 % and 41 %, these values are calculated averagely during the real-life monitoring period as 4 % and % 32.4 respectively. The results were reported using the international evaluation parameters. The main reasons of the difference between the simulated and practical calculated values are the partial shadow effects and the limited energy generation due to the low load demand.

Implementation of Maximum Power Point Tracking Control in Single Phase Utility Interconnected Photovoltaic Inverter

This paper presents an implementation of maximum power point tracking control in a single phase utility interconnected photovoltaic inverter. The control algorithm is based on the perturbation and observation method, and realized by a PIC microcontroller which controls the entire supervisory task in the system. To operate P&Q algorithm properly a PV voltage control loop is added. The characteristic performance of the MPP algorithm is obtained by simulation and verified by experiments. Daily operation results are also included.