Self-Normalized-Estimator-Based Control for Power Management in Residential Grid Synchronized PV-BES Microgrid

Abstract

This paper presents a residential photovoltaic (PV) battery energy storage (BES) based three-phase grid synchronized microgrid. The objective of the proposed microgrid is to develop a fully autonomous power management scheme in utility-integrated and islanded modes. To control the PV-BES microgrid in grid-tied mode, the self-normalized estimator (SNE) control is used for power management. Besides, having seamless transfer capability, the proposed microgrid mitigates power quality disturbances caused by nonlinear loads tied at point of common coupling (PCC). Moreover, a PV feed-forward term is incorporated in SNE algorithm for the injection of active power to the utility as well as to improve the dynamic behavior of the PV-BES based microgrid. The controlled buck–boost converter enables the charging /discharging of the BES by importing or exporting the power into it. Here, the power fluctuations are suppressed by utilizing BES because of the characteristic of PV source at irradiance changes. The proposed control takes into account the extracted maximum PV power and BES conditions to supply the uninterruptible power to nonlinear loads. The efficacy of the SNE-based control for the microgrid is validated experimentally on a prototype developed in the laboratory at nonlinear load connected at the PCC.