A comparative analysis between the tracking solutions implemented on a photovoltaic string

The paper deals with a comparative analysis (in terms of energetic efficiency) between the mono-axis and dual-axis tracking solutions implemented on a photovoltaic (PV) string. The study reveals which solution is more efficient in the geographical area of Brasov, and under which conditions. The tracking efficiencies of the mono-axis and dual-axis systems are compared considering two orientation programs: seasonal and annual. Taking into account the technical and economical aspects, besides the energy gain of the dual-axis system, it was concluded that a mono-axis tracking system is preferred for the studied geographical area. The study is performed by using the virtual prototype of the PV tracking system, which is approached in mechatronic concept. An algorithm for the optimal design of the step-by-step tracking law is also developed, the maximization of the energetic efficiency of the PV string with solar tracker being the optimization goal. Finally, experimental data are used to validate the simulation results. (C) 2014 AIP Publishing LLC.