引用本文: | 郭晓瑞,郭吉丰,龙英文.三相全数字频率自适应闭环锁相技术[J].电力自动化设备,2013,33(2): |
| GUO Xiaorui,GUO Jifeng,LONG Yingwen.Digital frequency-adaptive PLL technique for three-phase grid-connected inverter[J].Electric Power Automation Equipment,2013,33(2): |
|
摘要: |
针对三相分布式并网系统中并网电压畸变严重时传统锁相方法精度不高和市电频率突变而引起锁相精度变差的现象,结合开环锁相与闭环锁相的优点,提出了一种新的频率自适应三相全数字闭环锁相新算法。新的锁相算法采用带有自适应控制的二阶低通滤波器滤除市电电压中高频谐波,可以有效地抑制市电电压基波负序和高频谐波的干扰,快速准确地追踪市电电压正序基波分量的相位。最后,通过仿真将改进后的数字锁相方法与已有的开环、闭环锁相方法进行比较,仿真及实验结果表明该锁相方法的正确性及实用性。 |
关键词: 三相并网系统 正序 锁相环 自适应控制 |
DOI: |
分类号: |
基金项目: |
|
Digital frequency-adaptive PLL technique for three-phase grid-connected inverter |
GUO Xiaorui1, GUO Jifeng1, LONG Yingwen2
|
1.College of Electrical Engineering,Zhejiang University,Hangzhou 310027,China;2.Hefei University of Technology,Hefei 230009,China
|
Abstract: |
Aiming at the low accuracy of traditional PLL(Phase Locked Loop) under the conditions of seriously distorted grid voltage and abrupt frequency variations,an all-digital PLL algorithm with frequency-adaptation function is presented for the three-phase grid-connected inverters,which adopts the adaptive second-order low-pass filter to effectively suppress the line negative-sequence fundamental and harmonic components and to quickly track the line positive-sequence fundamental phase with little distortion. The proposed method is compared with existing open-looped and closed-looped methods,and the simulative and experimental results show its correctness and feasibility. |
Key words: three-phase grid-connected system positive sequence phase locked loops adaptive control |