基于改進S變換的微網諧波檢測方法
王曉光1，吳素敏1，吳麗娜2，劉觀起2
1 國網浙江云和縣供電公司，浙江 云和 323600；
2 華北電力大學 電氣與電子工程學院，河北 保定 071003
摘 要：針對S變換受噪聲影響較大的缺陷，提出了基于改進S變換的微網諧波檢測方法。對諧波信號進行改進S變換，根據變換所得的復數時頻矩陣提取特征量，進一步檢測諧波的頻次、幅值和相位，實現穩態諧波的檢測和暫態諧波的時間定位。仿真結果表明，該諧波檢測方法精確度高且抗噪性強，為微網的諧波檢測提供了一種有效方法。
關鍵詞：改進S變換；諧波檢測；微網
中圖分類號：TM935 文獻標識碼：A 文章編號：1007-3175(2015)02-0043-04
Harmonic Detection Method for Micro-Grid Based on Modified S-Transform
WANG Xiao-guang1, WU Su-min1, WU Li-na2, LIU Guan-qi2
1 State Grid Zhejiang Yunhe Power Supply Bureau, Yunhe 323600, China;
2 School of Electrical and Electronic Engineering, North China Electric Power University, Baoding 071003, China
Abstract: Aiming at the defect that the noises impacted on the S-transform greatly, this paper presented a harmonic detection method for micro-grid based on the modified S-transform, to carry out S-transform for the harmonic signals. The feature vectors were extracted from the complex number time-frequency matrix of S-transform, detecting the frequency, amplitude and phase of the harmonics further, to realize the steady state harmonic detection and the transient state harmonic time positioning. Simulation results show that the proposed approach can detect the harmonic in micro-grid with high accuracy and strong noise immunity, which provides an effective means for harmonic detection in micro-grid.
Key words: modified S-transform; harmonic detection; micro-grid
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