K. Edelmoser, F. Himmelstoß:
"Dual Filter Stage for EMI-Optimized Soalr Inverter Array";
Poster: International Conference on Power Electronics and Intelligent Motion (PCIM), Nürnberg, Germany; 05-17-2011 - 05-19-2011; in: "Proceedings PCIM Europe 2011", (2011), ISBN: 978-3-8007-3344-6; 1163 - 1168.

In the field of electrical solar power conversion efficiency is the most important topic. Also the elimina-tion of high frequency ripple on input- and output side is an increasingly important topic. In common single-phase inverter applications the current of the solar array shows a remarkable ripple due to power pulsation on the grid. This entails two significant disadvantages: Reduced over-all efficiency due to dynamic maximum power point mismatch and reduced lifetime of the panels due to additional com-ponent stress. Furthermore in environments with several solar strings operating in parallel to reach the goal of a very close MPP operation, a distributed current source arrangement has to be chosen. On the other hand, several measurements have also to be taken into consideration to keep the output-harmonics in an acceptable range. The proposed topology discussed in this paper uses separated ac-tive filters to fulfil the given requirements: Minimized input current ripple of the cells, string-optimized maximum power point tracking and optimal power quality of the supplying grid. The topology presented in this paper shows a remarkable improvement of the over-all efficiency as well as a significantly en-hanced EMC. Consequently, it is well suited for solar power inverter applications.

http://publik.tuwien.ac.at/files/PubDat_197214.pdf