Design of a Power-Conditioning System for Trans-Z-Source Inverter to Connect Photovoltaic Arrays to Single-Phase Household Electrical Grid

Abstract In this paper, a new type of single-level power-conditioning system for photovoltaic arrays connected to the single-phase grid is presented in which transformer-based impedance source inverter (Trans-ZSI) is employed to reduce cost and volume, and meanwhile to improve the efficiency. As a b...
Ausführliche Beschreibung

Abstract In this paper, a new type of single-level power-conditioning system for photovoltaic arrays connected to the single-phase grid is presented in which transformer-based impedance source inverter (Trans-ZSI) is employed to reduce cost and volume, and meanwhile to improve the efficiency. As a buck–boost inverter, the Trans-Z-source inverter includes just an inverter bridge and a passive network, which itself consists of a pulse transformer and a capacitor. This inverter can be an appropriate alternative for the common structures consisting of inverters and DC/DC converters. In this article, presenting an efficient controlling method, Trans-Z-source inverter is used to connect the photovoltaic system to a single-phase grid. In the controlling structure, the improved INC method is proposed to track the maximum power point, while the proportional–resonance and proportional–integral controllers are employed to inject power to the grid and stabilize the Trans-ZSI capacitor voltage, respectively. Simulations show the functionality of the proposed system. Ausführliche Beschreibung