基于STC12C5408AD光伏并网发电系统设计.pdfVIP

学兔兔 总第47卷 第531期 电测与仪表 V0l 7 NO．5粤l 2010年 第03期 Electrical Measurement＆Instrumentation ^db帆l2OlO 基于STC 12C5408AD光伏并网发电系统设计母 朱士虎，王立巍 (徐州师范大学物理与电子工程学院，江苏徐州221116) 摘要：在光伏系统中，由于光伏电池的光电转换效率太低，使其不能以最大效率转化为电能输出，最大功率点跟 踪是光伏并网发电系统中的核心问题。系统设计采用电流型控制芯片UC3845实现最大功率点跟踪(MPPT)，由 单片机STC12C5408AD产生SPWM信号，实现频率相位跟踪功能、输入欠压保护功能、输出过流保护功能。结果 表明，该设计不但电路设计简单，软硬件结合，控制方法灵活，而且能够有效地完成最大功率跟踪的目的，明显 提高光伏发电系统的整机效率。 关键词：STC12C5408AD；DC—AC转换电路；MPPT 中图分类号：TM464 文献标识码：B 文章编号：1001—1390(2010)03—0020—04 Desi~ of Grid-connected Photovoltaic System Based on STC12C5408AD ZHU Shi—hu，WANG Li—wei (School ofPhysicsElectronic Engineering，Xuzhou Normal University，Xuzhou 221 1 16，Jiangsu，China) Abstract：The low photoelectric conversion efficiency is a major drawback of photovohaic cells in photovohaie systems， SO that it call not be turned into the most efficient power output．Maximum Power Point Tracking is one of the most important problems for the grid-connected photovohaic system．MPPT can be achieved using the current control chip UC3845，and．MCU produces the SPWM signa1．The system has many functions，such as frequency and phase track function，and the protection function of input voltage lack and output current overflow．The result shows that this system not only has simple circuit design and flexible control method，but also can achieve the target of maximum power point tracking effectively．And the efficiency of system is approved apparently with the method． Key words：STC 1 2C5408AD，DC—AC conversion circuit，MPFF 0 引 言 纳法的MPPT