Design for reliability of multifunctional PV inverters used in industrial power factor regulation

Industrial consumers are widely known for their high demand for active and reactive power. Thus, these consumers have a great interest in the local generation using PV plants to reduce the energy bill. However, the traditional PV systems reduce the active power absorbed from the grid and, consequently, the installation power factor. Under such conditions, fees are being charged due to the low facility power factor. This work carries out an overall study on the effects of the installation of a PV plant on the industrial power factor. Moreover, solutions based on traditional capacitor banks or multifunctional PV inverters are benchmarked. The case study of an industrial power plant located in Brazil is discussed. The results indicate that the traditional capacitor bank solution cannot correct the power factor all time due to its limited number of taps. Nevertheless, the multifunctional PV inverter can provide a precise reactive power compensation, which improves the power factor and eliminates the additional fees. However, a PV system reliability reduction of 24.1% is observed compared to the traditional operation, while inverter oversizing preserves the system reliability even by correcting power factor.