DYNAMIC MATCHING OF A SOLAR-ELECTRICAL (PHOTOVOLTAIC) SYSTEM - AN ESTIMATION OF THE MINIMUM REQUIREMENTS ON THE MATCHING SYSTEM.

In order to achieve maximum energy transfer from the solar cell array to the load and the storage batteries (whose parameters are variable), a dynamic matching between the array and the other system elements should be achieved. In a related paper, it was shown that such matching can be done by means of a switching arrangement which acts as a ″DC transformer″ with a discrete transformation ratio, T//i. Although continuous change can be achieved by an invertor, for example, this element causes power reduction, is expensive and introduces reliability problems. A better approach is by introducing a ″DC transformer″ , (DCT), which interchanges the connections of cells and modules. The ″DCT″ is not always fully matched and therefore some small reductions are small. The goal of this paper is to establish the minimum number of discrete transformation values, T//i, needed to assure a sufficiently close approximation to maximum energy supply to the system.