A Simple PV Inverter Power Factor Control Method Based on Solar Irradiance Variation

There has been a significant rise in photovoltaic (PV) system installations throughout the last decade. This has posed some technical challenges to the distribution grid operators. Unfamiliar impacts of these relatively new energy sources now should be handled more comprehensively. The rigidity of these impacts mostly depends on PV penetration level, grid and weather characteristics as well as the interaction of load and generation. In this study, a reactive power control method is proposed benefitting from solar irradiance measurements in weather stations. Accordingly, power factors of PV inverters are regulated by a simple analytical conversion. The effectiveness of the method is demonstrated by reducing the tap change operations of substation transformer. In addition, loading ratios of overhead lines and secondary distribution transformers, and voltage profiles are analyzed considering all the three phases separately. Quasi-static simulations are carried out for two representative days in GridLAB-D by using a modified IEEE 13 node test feeder.