Self-Adjustable Step-Based Control Algorithm for Grid-Interactive Multifunctional Single-Phase PV-Battery System Under Abnormal Grid Conditions
Shailendra Kumar, Laxmi Narayan Patel, Bhim Singh, A. L. Vyas
Abstract
This article deals with the single-phase grid interactive multifunctional solar PV (photovoltaic) system with seamless power transfer capability. This multifunctional PV-battery system is also helpful to enhance the quality of power in the utility grid. The system provides an uninterrupted power to nonlinear loads during the nonavailability of utility and renewable energy resource. This PV-battery system comprises two stages. First stage is a PV array-boost converter along with a battery energy storage-bidirectional converter that is integrated at dc-link and another is voltage source converter (VSC), which performs the task of harmonics elimination and injection of harvested energy to the utility along with nonactive power compensation. In standalone mode, the shape of load voltage is sustained sinusoidal by islanded technique. A proportional integral controller is used to sustain the dc-link voltage to a specific value. In order to improve the dynamic response of the PV-battery system, a feedforward control for solar PV participation is used. A self-adjustable step-based control is introduced for the VSC in this work. This estimates the real power reflecting portion of the load current in order to show the features of the PV-battery system. Simulation studies are carried out in MATLAB Simulink. The experimental performance of the developed PV-battery system is found satisfactory even under abnormal grid condition.