光伏逆变器实时能效分析

Real-time Energy Loss Analysis of PV Inverters

讨论光伏逆变器系统的能量损耗,从机理角度研究了系统中各部分损耗来源,给出了计算方法及其在逆变器实时损耗分析中的应用。首先介绍了常用三相光伏逆变器的基本结构,从其结构可以看出,可能的损耗来源是IGBT、反向二极管、直流侧电容、LCL滤波器、升压变压器、控制电路及冷却系统等。其次,对各部分损耗来源进行了分析,并给出了一套简单精确的计算方案,用于实时计算逆交器损耗。最后,通过实验和仿真评估了计算方案的精确性和实时性,并根据光伏系统的光照度、温度曲线计算了逆变器各部分日损耗曲线。本文提出的计算方法为逆变器的设计提供了一定的依据。

The paper discusses the energy loss in PV inverter system, analyzes the cause of the loss in the system from the mechanism, and introduces the calculation method for the loss and its application in real time analysis of inverter. Firstly, the paper introduces the basic structure of three-phase photovultaic inverter. As can be seen from its structure, the loss may be caused by IGBT, reverse diode, DC side capacitor, LCL filter, boost transformer, control circuit and cooling system. Then the paper analyzes the possible causes for the loss in each part, and proposes a simple and accurate calculation method for the real time calculation of inverter loss. The accuracy and real-time performance of this method is evaluated by experiments and simulations. Finally, the daily loss cure of each part of the inverter is calculated according to the light intensity and temperature curve of the photovohaic system. The calculation method proposed in this paper provides a basis fur the design of inverter.