Power factor and harmonic distortion optimization in a photovoltaic generating power station

The paper deals with the problem of optimising the interface of a photovoltaic power station with the electrical power system. Firstly, a typical scheme based on the direct DC/AC conversion of the electrical power produced by the photovoltaic cells, obtained by means of line commutated converters, is critically analysed. Then, a solution based an a double conversion, DC/DC and DC/AC, is presented. The DC/DC conversion, based on a boost converter, is controlled to optimise both the power delivered from each sub-field of the photovoltaic field and the voltage level of a common DC link. The DC/AC conversion optimises the output quantities on the AC system busbar in terms of power factor, distortion levels and other characteristics of interest. The DC/DC conversion system, representing the core of the proposed solution, is simply modeled for some initial analyses also performing numerical experiments