正序基波提取器在光伏并网功率调节系统中的应用.pdf

第41卷第20期
史力系犹保护控制
Vol 41 No 20
2013年10月16日
Power System Protection and Control
Oct.16,2013
正序基波提取器在光伏并网功率调节系统中的应用
杨艺云,司传涛,廖波,周林2
(1.广西电网公司电カ科学研究院,广西南宁530023;
2.重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030
摘要:光伏并网功率调节系统实现光伏并网与有源潓波的统一控制,关键是谐波、无功电流的准确检测和并网指令电流的形
成。考虑实际电网电压有畸变或频率偏差,为获得准确谐波、无功电流和同步正弦,利用幅值积分及其频率选择特性构成正
序基波提取器,深入分析正序基波提取器中〖参数设计方法,推导出K值的计算表达式,合理取值,可准确提取正序基波,
无需锁相环可得到同步正、余弦信号。分析了谐波、无功及不对称分量之和的检测方法和并网指令电流的合成方式,实现光
伏有功注入与谐波抑制、无功补偿功能。最后进行 Matiab/ Simul ink仿真,仿真结果验证了理论分析的正确性。针对K参数
对正序基波提取的影响,完成了其小功率实验,实验结果进一步证明该方法的正确性。
关键词:光伏并网功率调节系统;正序基波提取器;谐波检测;〖参数;指令电流合成
Positive-sequence fundamental wave extractor applied in the P grid-connected power conditioning system
YANG Yi-yun, SI Chuan-tao', LIAO Bo, ZHOU Lin?
(1. Electric Power Research Institute of Guangxi Power Grid Corporation, Nannin 530023, China
2. State Key Laboratory of Power Transmission Equipment System Security and New Technology
Chongqing University, Chongqing 400030, China)
Abstract: The key for PV grid-connected power condition s em o realize the uniform control of PV grid-coneted and active
filter is to correctly detect harmonic and reactive current and form grid-connected directive current. Considering distortion and
frequency deviation of the actual grid voltage, to get the correct harmonic, reactive current and synchronous sine, the amplitude
integral and selective characteristic of frequen are used o form the positive sequence fundamen al extractor. The K in the positive
sequence fundamental extractor is further analyzed, and then the operation expression of K is derived. If K is chosen properly
positive-sequence fundamental can be got correctly, and sychronous sine and cosine can be got without the phase lock loop. The
detecting method for the harmonic, reactive power, and the sum of unsymmetrical components, as well as the grid-connected
directive current composing method is analyzed to realize the active power injection, harmonic eliminating and reactive power
compensation. The simulation in Matlab/Simulink verifies the corectness of the theoretical analysis. For the effect ofk on the
positive-sequence fundamental extracting, the miniwatt expriment is conducted to further verify the correctness of the method
Key words: grid-connected photovoltaic power conditioning stem; positive sequence fundamental wave extractor; harmonic
detecting; parameter K; directive current composing
中图分类号:TM76文献标识码:A
文章编号:1674-3415(2013)20-0067-08
0引言
有源电力滤波器主电路和控制方式相似,将光伏并
网系统与有源滤波统一控制,实现光伏并网功率调
光伏并网发电是利用太阳能的有效手段之节系统例,既能向电网输送有功功率,同时能补偿
リ,随着国家政策大力支持与发展的需要,光伏一定诸波和无功,提高了光伏并网系统的利用效率,
并网系统容量不断增大,而光伏发电具有间歇性、改善电网电能质量,也节省了其他无功补偿设备。
功率波动性等特点2,导致其在一些时段不能工作
从目前的报道看,国内外已经对光伏并网功率
于额定状态,尤其是晚上光伏系统不能发电并网,调节系统进行了一些研究3,1?,目前的研究都并未
并网逆变器利用率不高。考虑光伏并网发电系统与详细考虑电网电压畸变或不平衡的实际情况,且采