Impact of optimum power factor of PV-controlled inverter on the aging and cost-effectiveness of oil-filled transformer considering long-term characteristics

摘要： The photovoltaic (PV) system is one of the most widespread of the renewable energy generation systems that are being used to meet the continuously increasing energy demand. A proposed analytical method is used to find the optimum power factor of PV inverter (PVI) that leads to minimum aging, reduced energy losses cost of the transformer, lower payback period of PV system, and lower green houses gases (GHG) emissions due to the transformer energy losses. In this study, the thermal performance of a 630?kVA mineral oil-filled transformer is simulated in MATLAB programming language. For an association, it is mandatory to connect a PV system to the grid to minimise the transformer loading. The PV output power is used to study the long-term impact of the solar irradiance on the transformer thermal performance. Also, the long-term climatic characteristics are considered. The ambient temperature surrounding the transformer is considered all day long. The load current profile was measured all day long. The results show the aging and cost-effectiveness of the transformer and the payback period of PV system and GHG emissions are a function of PVI power factor.