基于改進(jìn)S變換的微網(wǎng)諧波檢測(cè)方法
王曉光1,吳素敏1,吳麗娜2,劉觀起2
1 國(guó)網(wǎng)浙江云和縣供電公司,浙江 云和 323600;
2 華北電力大學(xué) 電氣與電子工程學(xué)院,河北 保定 071003
摘 要:針對(duì)S變換受噪聲影響較大的缺陷,提出了基于改進(jìn)S變換的微網(wǎng)諧波檢測(cè)方法。對(duì)諧波信號(hào)進(jìn)行改進(jìn)S變換,根據(jù)變換所得的復(fù)數(shù)時(shí)頻矩陣提取特征量,進(jìn)一步檢測(cè)諧波的頻次、幅值和相位,實(shí)現(xiàn)穩(wěn)態(tài)諧波的檢測(cè)和暫態(tài)諧波的時(shí)間定位。仿真結(jié)果表明,該諧波檢測(cè)方法精確度高且抗噪性強(qiáng),為微網(wǎng)的諧波檢測(cè)提供了一種有效方法。
關(guān)鍵詞:改進(jìn)S變換;諧波檢測(cè);微網(wǎng)
中圖分類號(hào):TM935 文獻(xiàn)標(biāo)識(shí)碼:A 文章編號(hào):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
參考文獻(xiàn)
[1] Cho C H, Jeon J H, Kim J Y, et al.Active synchronizing control of a microgrid[J].IEEE Transactions on Power Electronics, 2011,26(12):3707-3719.
[2] Wagner VE.Effects of harmonics on equipment[J].IEEE Transactions on Power Delivery,1993,8(2):672-680.
[3] Sanoso S,Grady W M,Powers E J,et al. Characterization of distribute power quality events withFourier and wavelet transforms[J].IEEE Transactions on Power Delivery,2000,15(1):247-254.
[4] 周龍華,付青,余世杰,等.基于小波變換的諧波檢測(cè)技術(shù)[J].電力系統(tǒng)及其自動(dòng)化學(xué)報(bào),2010,22(1):80-85.
[5] Julio Barros, Ramon Diego.A new method for measurement of harmonic groups in power system using wavelet analysis in the IEC standard framework[J].Electric Power Systems Research, 2006,76(4):200-208.
[6] 任震.小波分析及其在電力系統(tǒng)中的應(yīng)用[M].北京:中國(guó)電力出版社,2003.
[7] 李明,王曉茹.一種用于電力系統(tǒng)間諧波譜估計(jì)的自回歸模型算法[J].中國(guó)電機(jī)工程學(xué)報(bào),2010,30(1):72-76.
[8] 王好娜.采用神經(jīng)網(wǎng)絡(luò)的諧波和間諧波檢測(cè)方法研究[D].重慶:重慶大學(xué),2011.
[9] Stockwell R G, Mansinha L, Lowe R P. Localization of the complex spectrum:the S transform[J].IEEE Transactions on Signal Processing, 1996,44(4):998-1001.
[10] Pinnegar C R,Mansinha L.The S-transform with windows of arbitrary and varying shape[J].Geophysics,2003,68(1):381-385.
[11] 程志友,梁棟,韋穗,等.基于S變換的動(dòng)態(tài)間諧波檢測(cè)方法研究[J].電測(cè)與儀表,2007,44(3):5-8.