Control strategies for power converters used on solar cells

The sun is considered as the major source of energy to the human kind from the beginning of life. This energy is radiated to earth by means of light and heat. We have been harnessing the solar energy for centuries and decades. The world is facing, especially in the recent years, a tremendous increase of energy demand from Asian to European and growing American countries as well as the traditional high energy demand from industrial countries. One solution to these problems is becoming so obvious, mass production and use of electricity generated from renewable energy especially solar energy, which is environmentally friendly. There are important applications of solar cells under development that directly relate to the field of power electronics, making ground for new opportunities in applications for low, medium and high power, for both DC and AC systems. High costs of conversion efficiency have been the major inconvenience in the potential of solar power becoming a primary source of energy. In our days, major researches done with the motive of improving the efficiency of these cells has brought this dream closer to reality. The technology proposed in this thesis is based on the idea that it is much more cost-effective to improve the solar cells by incorporating a smart control of power electronics than to improve the efficiency of the solar cells material by itself. The thesis came across a new idea of simulating the Cuk converter using estimation techniques with full and reduced-order observers adding to them the integral action to make the converter more and more competent. Great results were demonstrated with a very high performance. The thesis also presents two major and efficient control algorithms for the Maximum Power Point Technique (MPPT); fuzzy logic control and its high reliability with very dynamic and weather related systems and the jump parameter linear control technique with an efficient algorithm.M.S.Includes bibliographical referencesby Elias Selwa