【摘要】：近年來,隨著非線性負(fù)載設(shè)備廣泛使用于電力系統(tǒng)中,電網(wǎng)的諧波產(chǎn)生了十分嚴(yán)重的污染。目前抑制電網(wǎng)諧波和無功補(bǔ)償?shù)闹饕�裝置是有源電力濾波器,其關(guān)鍵環(huán)節(jié)是能夠?qū)崟r(shí)準(zhǔn)確的檢測諧波電流。目前諧波電流檢測有許多種方法,其中屬赤木泰文提出的“瞬時(shí)無功功率理論”應(yīng)用最為廣泛。 基于瞬時(shí)無功功率理論的三相諧波電流檢測方法有p-q法、ip-iq法。其原理是將三相電路電壓和電流的瞬時(shí)值變換到α-β兩相正交的坐標(biāo)系上進(jìn)行研究。該方法能在三相電壓對(duì)稱且無畸變的情況下準(zhǔn)確檢測出基波電流分量,但也存在著自身的局限性。例如在電網(wǎng)電壓畸變、三相電路不對(duì)稱時(shí)檢測存在誤差；不能直接應(yīng)用于三相四線制電路；無法檢測出所需的特征次諧波電流等。 針對(duì)上述問題,本文進(jìn)行了一系列的改進(jìn)措施：無鎖相環(huán)檢測法省去了傳統(tǒng)檢測方法中的鎖相環(huán)電路,使檢測結(jié)果不受電壓畸變的影響：利用對(duì)稱分量法提取基波正序電壓,可以有效解決三相電壓不對(duì)稱造成的對(duì)基波有功電流檢測的影響；通過零序電流分離單元可提取出不對(duì)稱三相電流中的零序分量,使得諧波檢測能夠在三相四線制電路中得以應(yīng)用。 此外,一種廣義瞬時(shí)無功功率理論的發(fā)展,突破了原有僅能檢測所有諧波電流之和的傳統(tǒng)理論,從而使故障中對(duì)應(yīng)的特征次諧波電流檢測成為可能。在此基礎(chǔ)上,提出了一種基于廣義瞬時(shí)無功功率理論的任意次諧波電流檢測法。該算法在傳統(tǒng)ip-iq法的基礎(chǔ)之上,適當(dāng)修改變換矩陣,檢測出三相不對(duì)稱系統(tǒng)中任意次諧波的正、負(fù)序分量,然后通過等價(jià)三角變換得到各相電流零序分量,三者相加即可得到所需的諧波電流。 最后,使用Matlab中的simulink軟件進(jìn)行電路模型仿真和理論分析,并對(duì)檢測波形進(jìn)行頻譜分析。結(jié)果表明,該算法具有很高的準(zhǔn)確性和靈活度。
[Abstract]:In recent years, with the wide use of nonlinear load equipment in power system, harmonic generation of power network has caused serious pollution. At present, active power filter is the main device to restrain harmonic and reactive power compensation of power network. The key link of active power filter is to detect harmonic current in real time and accurately. At present, there are many methods for harmonic current detection, among which "instantaneous reactive power theory" proposed by Akimuki Tyrman is the most widely used. The three phase harmonic current detection methods based on instantaneous reactive power theory are p-q method and ip-iq method. The principle is to transform the instantaneous value of voltage and current of three-phase circuit into 偽-尾 two phase orthogonal coordinate system. This method can accurately detect the fundamental current component in the case of three phase voltage symmetry and no distortion, but it also has its own limitations. For example, when the voltage is distorted and the three-phase circuit is asymmetrical, the error can not be detected; it can not be directly applied to three-phase four-wire circuit; the characteristic subharmonic current can not be detected, and so on. In order to solve the above problems, a series of improvement measures are proposed in this paper: the phase-locked loop (PLL) circuit in the traditional detection method is eliminated and the detection results are not affected by the voltage distortion. The fundamental positive sequence voltage is extracted by using the symmetric component method. It can effectively solve the influence of the asymmetry of three-phase voltage on the detection of fundamental active current. The zero sequence component of asymmetrical three-phase current can be extracted by zero-sequence current separation unit, and harmonic detection can be applied in three-phase four-wire circuit. In addition, the development of a generalized instantaneous reactive power theory breaks through the traditional theory, which can only detect the sum of all harmonic currents, thus making it possible to detect the characteristic subharmonic current in fault. On this basis, an arbitrary harmonic current detection method based on generalized instantaneous reactive power theory is proposed. Based on the traditional ip-iq method, the transformation matrix is modified appropriately to detect the positive and negative order components of any order harmonics in a three-phase asymmetrical system, and then the zero sequence components of each phase current are obtained by equivalent trigonometric transformation. The harmonic current required can be obtained by adding the three. Finally, the circuit model simulation and theoretical analysis are carried out by using simulink software in Matlab, and the spectrum analysis of the detection waveform is carried out. The results show that the algorithm has high accuracy and flexibility.
【學(xué)位授予單位】：浙江大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TM933.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 韓松,邱國躍,彭小俊;相位差θ對(duì)諧波及無功電流檢測的影響分析[J];電測與儀表;2005年04期

2 卓放,楊君,胡軍飛,王兆安;三相四線制有源電力濾波器主電路的結(jié)構(gòu)形式與控制[J];電工電能新技術(shù);2000年02期

3 楊萬開,肖湘寧,楊以涵;不對(duì)稱三相電路畸變電流和負(fù)序電流的一種實(shí)時(shí)檢測方法[J];電工電能新技術(shù);1998年01期

4 王兆安;李民;卓放;;三相電路瞬時(shí)無功功率理論的研究[J];電工技術(shù)學(xué)報(bào);1992年03期

5 周林;夏雪;萬蘊(yùn)杰;張海;雷鵬;;基于小波變換的諧波測量方法綜述[J];電工技術(shù)學(xué)報(bào);2006年09期

6 楊君，，王兆安;三相電路諧波電流兩種檢測方法的對(duì)比研究[J];電工技術(shù)學(xué)報(bào);1995年02期

7 翁利民,陳允平,吳軼群;配電網(wǎng)的諧波源特性與高次諧波的抑制[J];電力電容器;2001年04期

8 楊樺,任震,唐卓堯;基于小波變換檢測諧波的新方法[J];電力系統(tǒng)自動(dòng)化;1997年10期

9 王建賾,冉啟文,紀(jì)延超,柳焯;基于小波變換的時(shí)變諧波檢測[J];電力系統(tǒng)自動(dòng)化;1998年08期

10 張波,易頌文,何曉敏;基于廣義d_k-q_k旋轉(zhuǎn)坐標(biāo)變換的諧波電流檢測方法[J];電力系統(tǒng)及其自動(dòng)化學(xué)報(bào);2001年03期

本文編號(hào)：2299240