Comprehensive Quantitative Evaluation of the Photovoltaic Grid-Connected Power Generation System Adopting nX DC/DC Converter

In this article, a new nX dc/dc converter-based photovoltaic (PV) power system is proposed. This kind of converter is the ideal transformer for PV power generation system, which has the advantages of small size, lightweight, high efficiency, large voltage ratio, high temperature resistance, and low cost, but its discrete voltage gain leads to the deviation in maximum power point tracking. So, this article compares nX dc/dc with boost converter in terms of series loss of PV modules, maximum power tracking (MPPT) effects, overall efficiency, and costs of power devices, in order to evaluate the performance of nX dc/dc converter-based PV system. Then, two types of converter-based PV power generation system are established using MATLAB, and the effects of MPPT in each system are texted under the condition of floating solar radiation intensity. Both theoretical analysis results and simulation results demonstrate that nX dc/dc is worse at MPPT than boost converter, but due to its lower self-loss, nX dc/dc has higher overall efficiency and improves the reliability of the PV systems.