郑州大学毕业设计（论文）
题 目： 3KW光伏并网逆变器的软件设计 指导教师： 职称： 教授
学生姓名： 学号： 专 业： 院（系） ： 完成时间： 2010年5月
2010 年 5 月 26 日
摘 要
太阳能作为当前人类最理想环保的新能源之一，己经得到人类越来越广泛的应用。而光伏并网逆变器是太阳能并网发电系统中必不可少的设备之一。
光伏并网逆变器是将太阳能电池所输出的直流电转换成符合公共电网要求的交流电并送入电网的设备。按照不同的标准光伏并网逆变器的拓扑结构分为很多种，本文介绍了一种工频隔离型光伏并网逆变器。
首先，本文介绍了光伏并网逆变器的工作原理与分类。
其次，本文采用有效值外环、瞬时值内环的控制方法，既保证了逆变器输出的静态误差为零，又保证了逆变器良好的输出波形。
随后，本文详细讨论了并网过程中的软件锁相环技术，对锁相环电路的组成、工作原理进行了研究。
最后，采用TI公司的TMS320LF2407A作为主控芯片，完成了预期的设计。
关键词：光伏；并网发电；SPWM； 软件锁相环；自动控制
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Abstract
As one of the optimal new energy sources, the solar energy has been applied more and more widely by human being. And the grid-connected photovoltaic inverter is one of the necessary equipment of the grid-connected photovoltaic system.
The grid-connected photovoltaic inverter is a equipment which transform the DC from the solar cell to AC according with the grid and transports it to the public grid. According to different standard, the structure of the grid-connected photovoltaic inverter is various. This paper introduces a kind of line frequency isolated inverter.
Firstly, this paper introduces the principium and sort of grid-connected photovoltaic inverter.
Secondly, by using the control method of virtual value outer loop and instantaneous value inner loop，we can eliminate the static error, and make the output waveform well.
Subsequently，soft PLL was introduced in detail. The structure of Phase locked loop circuit and operating principle were researched.
Finally, TMS320LF2407A of TI incorporated is used as the main controller. We finally finish the desired design.
Key words: photovoltaic; grid-generation; SPWM; soft phase-locked-loop; Automatic control
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目 录
摘 要 ···························································································· I ABSTRACT ·················································································· II 第一章 绪论 ················································································ 1
1.1课题的研究背景与意义 ·································································································· 1 1.2 系统总体方案 ················································································································· 1 1.3 本文主要的研究内容 ····································································································· 2
第二章 光伏并网逆变器控制策略的研究 ······································· 3
2.1 光伏并网逆变器的分类 ································································································· 3 2.2 光伏并网逆变器控制目标 ····························································································· 4 2.3 基于SPWM的电压/电流型并网逆变器控制的研究 ····················································· 5
2.3.1 控制系统数学模型 ···························································································· 5 2.3.2 PI参数的设计 ··································································································· 6 2.3.3 基于SPWM的电压/电流型并网逆变器的控制方法 ········································ 8 2.3.4 SPWM信号的产生原理 ····················································································· 10 2.4 并网逆变器中同步锁相环的研究 ··············································································· 11
2.4.1 软件锁相环的基本原理 ·················································································· 12 2.4.2 基于光伏并网控制的软件锁相环的工作原理 ·············································· 12 2.4.3 并网控制中的锁相算法分析 ·········································································· 13 2.5 本章小结 ······················································································································· 14
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第三章 光伏并网发电系统软件设计 ·········································· 15
3.1 系统主程序流程图 ······································································································· 15 3.2 定时器中断子程序 ······································································································· 17 3.3 软件锁相环的设计 ······································································································· 19 3.4 控制系统软件抗干扰措施 ··························································································· 22 3.5 本章小结 ······················································································································· 23
第四章 总结与展望 ···································································· 24 致 谢 ························································································· 25 参考文献 ····················································································· 26 附录：文献翻译 ··········································································· 27
原文 ······································································································································· 27 文献翻译 ······························································································································· 35
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