Analysis of Smart Photovoltaic Module for Effective Use of Solar Energy

Abstract

The main objective of this thesis is to present a comprehensive investigation of residential PV grid-connected inverters and propose novel, practical topologies to address the unbalanced power generation between PV modules. This thesis proposed a modular inverter (MI) derived from a power electronic converter topology. The suggested single-stage modular Cuk inverter (MCI) in this thesis is designed by connecting multiple low voltage (LV) MIs in series and linking the output terminals to the distribution network. The recommended topology does not require a large DC-link decoupling capacitor, which is common in conventional central inverters. The decentralized features of the proposed MCI enhance the controllability of the residential PV system. The suggested MCI topology is designed based on the Cuk converter. Therefore, it offers continuous input and output current features, which enable the use of small-sized filter components. MCI topology operates over a broad range of voltages, which makes it suitable for supplying local loads or charging battery storage. The control system of the proposed topology consists of two control systems. In PV-to-grid mode, the input control loop at the PV side is designed to mitigate ripples in the input current, which commonly reduces the efficiency of the MPPT algorithm. On the other hand, the outer control system at the grid side is responsible for maintaining a sinusoidal waveform matched with the grid current. The Simulink simulation results illustrate the effectiveness of the proposed MI in mitigating the unbalanced power production of residential PV systems. Also, a scaled-down prototype experiment has been developed to validate mathematical and simulation analysis.