摘要
在新能源等采用变换器并网场合,电网同步信号检测是并网控制的关键。目前研究的锁相环电网同步方法还存在一定的缺陷,基于此,提出一种基于参考频率的电网同步信号实时检测方法,仅检测单相电网电压与参考频率正弦、余弦信号运算,在三相电网畸变、不平衡条件下能准确检测电网同步信号。针对电网出现频率偏移导致检测的同步信号存在较大的相位偏移,对检测过程中低通滤波环节引入负反馈和比例控制进行改进,可将相位偏移校正到满意的指标下。理论与实验研究结果均表明该方法的正确性和有效性。
The grid synchronization signal detection is a key to control the converter to be connected to the grid for new energy. For the weak points of the phase-lock loop, a grid synchronization signal real-time detecting method based on reference frequency is proposed in the paper. Only to detect the single-phase grid-voltage operated with sine and cosine signals of reference frequency, the grid synchronization signal can be detected in case of the three phase grid distorted and unbalanced. For the big phase deviation of the synchronization signal caused by frequency fluctuation, to improve the low-pass filtering link a negative feedback and proportional control is introduced, and the phase deviation can be corrected in satisfied index. The theoretical and experimental study results verify that the method is correct and effective.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2014年第9期1353-1359,共7页
Proceedings of the CSEE
基金
国家863高技术基金项目(2011AA05A301)
The National High Technology Research and Development of China 863 Program(2011AA05A301)
关键词
电网同步信号
参考频率
频率偏移
相位偏移
校正
grid synchronization signal
referencefrequency
frequency fluctuation
phase deviation
correction
作者简介
周林(1961),男,教授,博士生导师,研究方向为微网及可再生能源发电理论及应用;
晁阳(1988),女,硕士研究生,从事光伏并网无功电压控制技术研究,c729048086@163.com;
廖波(1986),男,硕士,主要从事变电电气一次设计与研究和新能源开发工作。