A multifunctional grid tied solar energy conversion system with ANF based control approach

Abstract

This paper presents a two stage, three-phase grid interfaced SPV (Solar Photovoltaic) energy conversion system with an ANF (Adaptive Notch Filter) based control algorithm. The proposed SPV system is a multi-function grid-interfaced solar PV energy conversion system, which along with conversion of dc-power from SPV to AC mains, is capable of reactive power compensation, harmonics current elimination and load balancing in a three-phase AC distribution system. Compared to multiple devices with different functionalities, a multifunction grid-interfaced SPV energy conversion system is capable to save substantially capital investment, space and maintenance cost. The ANF successfully extracts a single sinusoid of a possibly non-stationary nature from harmonics corrupted load currents at PCC (Point of Common Coupling). The control algorithm is adaptive with respect to the fundamental frequency of the system compared to other methods; and provides instantaneous values of the fundamental signals. Simulation and experimental results verify the validity of the presented algorithm and confirms its desirable transient and steady state performances. The THD (Total Harmonics Distortion) of grid currents is found well under IEEE-519 standard even under nonlinear loads.