Harmonics mitigation and phase compensation technique for 3P4W SPV system

Abstract

A three phase four wire (3P4W) grid supportive solar photovoltaic (SPV) system using a frequency-adaptive resonant (FAR) control approach is presented in this work. The SPV system injects the extracted power from the SPV array to the distribution network. Moreover, it also mitigates the neutral and harmonics current of the nonlinear loads connected at PCC (Point of Common Coupling). A perturb and observe (P and O) based maximum power point tracking (MPPT) technique is utilized to fulfill the objective of peak power extraction. In addition, to control the voltage source converter (VSC), a FAR control approach is used which is not only mitigates the harmonics current also produces an in-phase fundamental component from the load current. However, a PV feed-forward term is utilized to reduce the burden on proportional-integral (PI) controller of VSC. To validate the control approach of 3P4W SPV system, a prototype of 6 kW is built and tested in the laboratory under different operating conditions.