Optimized energy transfer from a photovoltaic system to electrical distribution network

In the first section of the paper, the influence of operating conditions on photovoltaic converters´ properties and characteristic is analyzed together with an optimization of their load. Then the function and technical treatment of a three-stage system of an optimized leading of the power of a photovoltaic generator to the electrical low voltage distribution network are described. In the first stage, the working point of individual photovoltaic generators of the solar source is optimized which assures the full utilization of the attainable power even under varying operating conditions (insolation, working temperature, extent of pollution). For a short time, the obtained energy is stored in accumulators or batteries of supercondensers, which constitute the second stage of the system. The third stage is a power chopper transforming the direct voltage of the accumulation component to the alternating voltage of the distribution network. The power of choppers can be controlled in dependence on the stage of charge of the accumulator or - if the capacitance of the battery is sufficient - according to the given diagram of the supplied energy to the network. In the conclusions, the results of testing of individual components of the system under real working conditions are given