| 引用本文: | 何英杰,邹云屏,刘飞,李辉,张玉成.一种改进自适应谐波检测算法研究[J].电力自动化设备,2006,(9):23-26 |
| .Improved adaptive algorithm of harmonic current detection[J].Electric Power Automation Equipment,2006,(9):23-26 |
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| 摘要: |
| 分析了传统定步长最小均方(LMS)算法用于谐波电流检测的不足,采用一种新的变步长LMS自适应算法检测谐波电流:根据误差信号e(n)和e(n-D)的自相关估计调整步长迭代,当权系数远离最佳权值时,通过增大步长加快对时变系统的跟踪速度;当权系数接近最佳权值时,减小步长获得较小的稳态误差。通过递推公式参数的选择,可对系统的收敛速度与稳态失调进行更灵活的控制。推导出了该方法的理论表达公式,其增加的计算量很小,容易实现。该方法能有效调节步长,不受谐波电流的干扰。仿真结果证明了该谐波电流检测方法的有效性。 |
| 关键词: 谐波检测,自适应滤波,变步长 |
| DOI： |
| 分类号:TM76 |
| 基金项目: |
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| Improved adaptive algorithm of harmonic current detection |
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HE Ying-jie ZOU Yun-ping LIU Fei LI Hui ZHANG Yu-cheng
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| Abstract: |
| Based on the study of disadvantages of conventional fixed step-size LMS(Least Mean Square) algorithm for harmonic current detection,an adaptive LMS algorithm with variable step-size is provided,which adjusts the step-size according to the autocorrelation estimation between e(n) and e(n-D).When the weight is far away from the optimal value,it increases the step-size to acce-lerate the tracking of time-variable system,while when the weight is near the optimal value,it decreases the step-size to minish the steady state error.By selecting appropriate parameters,the algorithm allows more flexible control of misadjustment and faster convergence speed.Its theore-tical approximate expressions are derived.It is easy to be implemented with little additional calculation.The algorithm can effectively adjust the step-size while maintaining the immunity against harmonic current disturbance.Simulation results illustrate its effectiveness. |
| Key words: harmonic detection,adaptive filtering,variable step-size |
