本文選題：小波分析 + Prony算法　； 參考：《哈爾濱工業(yè)大學(xué)》2015年碩士論文

【摘要】：我國(guó)跨省、跨區(qū)域電網(wǎng)的迅速發(fā)展促進(jìn)了電力能源的合理分配,但由于區(qū)域機(jī)組之間的網(wǎng)絡(luò)形式,長(zhǎng)距離交直流電力輸送,以及發(fā)電機(jī)快速勵(lì)磁的存在,致使系統(tǒng)運(yùn)行中負(fù)阻尼問題凸顯,導(dǎo)致電網(wǎng)中多次出現(xiàn)低頻振蕩(Low Frequency Oscillation),直接對(duì)各電廠的穩(wěn)定運(yùn)行造成了威脅,給國(guó)民經(jīng)濟(jì)的發(fā)展帶來了嚴(yán)重破壞,因此研究電力系統(tǒng)的低頻振蕩具有重要的意義。本文基于小波理論與Prony算法對(duì)電力系統(tǒng)低頻振蕩時(shí)的電壓和功率信號(hào)進(jìn)行分析,為電力系統(tǒng)隱極同步發(fā)電機(jī)低頻振蕩主導(dǎo)模式和阻尼分析提供可靠的理論及工程實(shí)際依據(jù)。首先,分析了低頻振蕩的產(chǎn)生條件及信號(hào)特征。由于電力系統(tǒng)模型復(fù)雜,很難建立起整個(gè)電力系統(tǒng)的動(dòng)態(tài)運(yùn)行數(shù)學(xué)模型,本文從局部發(fā)電機(jī)運(yùn)行狀態(tài)和輸出信號(hào)入手,分析了實(shí)際電力系統(tǒng)信號(hào)的非平穩(wěn)性和隨機(jī)性特點(diǎn)�？紤]到小波分析理論在信號(hào)時(shí)頻領(lǐng)域分析、非平穩(wěn)信號(hào)的去噪濾波和奇異值點(diǎn)敏感的檢測(cè)等方面具有良好的效果,因此先對(duì)數(shù)字濾波器和小波基本理論進(jìn)行研究。其次,分析了電力工程系統(tǒng)中的單機(jī)無窮大系統(tǒng)模型和隱極同步發(fā)電機(jī)的低頻振蕩機(jī)理,結(jié)合發(fā)電機(jī)的電、磁、機(jī)械統(tǒng)一特性,分析出發(fā)電機(jī)的轉(zhuǎn)子和定子之間的力矩不平衡導(dǎo)致的轉(zhuǎn)子頻率擺動(dòng)和勵(lì)磁調(diào)節(jié)器負(fù)阻尼是低頻振蕩的產(chǎn)生的根本原因。然后,以在線辨識(shí)的Prony算法為理論依據(jù)分析出電力系統(tǒng)低頻振蕩信號(hào)的特點(diǎn)。通過Matlab仿真驗(yàn)證了Prony算法對(duì)非平穩(wěn)信號(hào)估計(jì)時(shí),容易產(chǎn)生擬合階次高和易受噪聲影響的缺點(diǎn),進(jìn)而結(jié)合小波去噪濾波理論和奇異值點(diǎn)分析原理對(duì)電力系統(tǒng)低頻振蕩信號(hào)進(jìn)行分析,并利用Matlab仿真驗(yàn)證算法的可行性。同時(shí)經(jīng)過實(shí)驗(yàn)方法找到基于coif5小波基函數(shù)對(duì)發(fā)電機(jī)輸出信號(hào)濾波去噪分析的有效性。在工程上利用新疆哈密電廠的實(shí)際低頻振蕩數(shù)據(jù),驗(yàn)證了兩種算法結(jié)合的正確性。最后,介紹了發(fā)電機(jī)穩(wěn)定運(yùn)行在線監(jiān)測(cè)裝置的軟硬件實(shí)現(xiàn)。具體裝置實(shí)現(xiàn)過程:在GPS統(tǒng)一授時(shí)裝置信號(hào)的觸發(fā)下,系統(tǒng)采集發(fā)電機(jī)母線電壓和電流信號(hào)并通過AD轉(zhuǎn)化,經(jīng)過DSP與CPLD的簡(jiǎn)單運(yùn)算處理,數(shù)據(jù)通過光纖通信傳送給上位機(jī),利用后臺(tái)上位機(jī)VC++編程實(shí)現(xiàn)小波分析和Prony算法的結(jié)合得出信號(hào)的振幅、頻率、相位和衰減因子,為發(fā)電機(jī)運(yùn)行可視化界面顯示提供準(zhǔn)確的顯示信息,指導(dǎo)工作人員實(shí)時(shí)調(diào)控同步發(fā)電機(jī)的運(yùn)行狀態(tài)。實(shí)踐證明在線裝置實(shí)用性強(qiáng),能夠解決分析電力系統(tǒng)低頻振蕩的難題。
[Abstract]:The rapid development of cross-provincial and cross-regional power grids in China has promoted the rational distribution of power sources. However, because of the network form between regional units, the long distance AC / DC power transmission and the rapid excitation of generators,As a result, the problem of negative damping in the operation of the power system is prominent, and the low Frequency oscillation occurs many times in the power network, which directly threatens the stable operation of the power plants and brings serious damage to the development of the national economy.Therefore, it is of great significance to study the low frequency oscillation of power system.In this paper, based on wavelet theory and Prony algorithm, the voltage and power signals of low-frequency oscillation in power system are analyzed, which provides a reliable theoretical and engineering practical basis for the dominant mode and damping analysis of low-frequency oscillation of power system hidden pole synchronous generator.Firstly, the generating conditions and signal characteristics of low frequency oscillation are analyzed.Because the power system model is complex, it is difficult to establish the dynamic operation mathematical model of the whole power system. In this paper, the non-stationary and stochastic characteristics of the actual power system signal are analyzed from the operation state and output signal of the local generator.Considering that wavelet analysis theory has a good effect in signal time-frequency analysis, non-stationary signal de-noising filtering and singular-value point sensitive detection, the digital filter and wavelet theory are studied first.Secondly, the single machine infinite system model and the low frequency oscillation mechanism of the hidden pole synchronous generator are analyzed, and the unified characteristics of electric, magnetic and mechanical generator are combined.It is analyzed that the rotor frequency swing and the negative damping of the excitation regulator caused by the torque imbalance between the rotor and the stator of the generator are the fundamental causes of the low frequency oscillation.Then, the characteristics of low frequency oscillation signal of power system are analyzed based on the Prony algorithm of online identification.The Matlab simulation proves that the Prony algorithm is easy to produce the shortcomings of high fitting order and easy to be affected by noise when it is used to estimate non-stationary signals.Combined with wavelet denoising filtering theory and singular value point analysis theory, the low frequency oscillation signal of power system is analyzed, and the feasibility of the algorithm is verified by Matlab simulation.At the same time, the effectiveness of filtering and denoising analysis of generator output signal based on coif5 wavelet basis function is found by experimental method.The actual low frequency oscillation data of Hami Power Plant in Xinjiang are used to verify the correctness of the two algorithms.Finally, the hardware and software implementation of the on-line monitoring device for generator stable operation is introduced.Under the trigger of GPS unified timing device signal, the system collects generator bus voltage and current signals and transforms them through AD. After the simple operation of DSP and CPLD, the data is transmitted to the upper computer through optical fiber communication.Combining wavelet analysis with Prony algorithm, the amplitude, frequency, phase and attenuation factor of the signal can be obtained by using VC programming of background PC, which can provide accurate display information for the visual interface display of generator operation.Guide the staff to adjust and control the running state of synchronous generator in real time.Practice shows that the on-line device is practical and can solve the problem of analyzing low frequency oscillation in power system.
【學(xué)位授予單位】：哈爾濱工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TM712

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 余保東,孫建波,湯勝祥,吳欣然,梁虹;湖北電網(wǎng)低頻振蕩計(jì)算分析[J];電力系統(tǒng)自動(dòng)化;2001年15期

2 王志飛;李博;王巍;;基于神經(jīng)網(wǎng)絡(luò)和PRONY算法的電力系統(tǒng)諧波分析[J];甘肅聯(lián)合大學(xué)學(xué)報(bào)(自然科學(xué)版);2010年01期

相關(guān)博士學(xué)位論文 前1條

1 張新慧;基于Prony算法的小電流接地故障暫態(tài)選線技術(shù)[D];山東大學(xué);2008年

相關(guān)碩士學(xué)位論文 前1條

1 吳濤;聯(lián)合電力系統(tǒng)低頻振蕩的機(jī)理及抑制方法研究[D];華中科技大學(xué);2007年

，

本文編號(hào)：1757997