A High Performance PV-BES Energy Conversion System with High-Gain DC-DC Converter for On grid and off-Grid Applications

摘要

This paper presents a solar PV (Photovoltaic)-BES (Battery Energy Storage) based Energy Conversion System (PVBCS), comprising high gain DC-DC boost converter (HGBC), BES with a bidirectional converter and nonlinear loads. The HGBC is utilized to achieve high step-up voltage gain with simple structure. Two inductors of HGBC having the same level of inductance are discharged in series during off period of switch and are charged in parallel during on period of switch. Moreover, a voltage source inverter (VSI) is utilized for DC to AC power conversion and supplies the solar PV power to loads and the utility. Under the off-grid condition, VSI operates in voltage control mode. An enhanced power quality performance of the PVBCS is achieved by mSOGI-L (Modified Second Order Generalized integrator Loop) based D-Q transformation control. It eliminates the load current harmonics and generates the fundamental active component of AC current and voltage and reduces the complexity of VSI's control. Here, HGBC is realized the maximum power point in the solar PV array by via the MPPT algorithm. The bidirectional converter (BDC) coupled BES supports critical loads under the low PV array output and off-grid condition. Simulated results have presented under different steady state and dynamic conditions. to validate the acceptability of the system with control algorithm.