Design of capacitor bank in parallel to photovoltaic power plant

In order to ensure a large-scale application of PV generators in MV distribution system without unacceptable voltage changes due to drops of PV power output a simple, low-cost solution is developed. The solution includes operation of PV with predetermined leading power factor and addition of a capacitor bank in parallel to PV plant in order to compensate the reactive power absorbed by the PV inverters. Application of the developed negative-sequence current difference method for the unbalance protection of the capacitor banks enables to achieve a compact and cost-reduced design of the banks connected in parallel to PV power plants.