【正文】 ng with high presicion.2）According to the spectrum characteristics of harmonics/interharmonics, an approach is proposed to pute harmonics/interharmonics in real time. Considering the characteristic of sine/cosine function, the harmonic ponent can be transformed into DC ponent, the rms value and initial phase angle of harmonic then can be got after lowpass filtering. As to interharmonics, it is generally considered to be a challenge because the interharmonics only have small ratio, it is hard to estimate them accurately. By subtracting fundamental and harmonic ponents from the original signal, maximum spectrum searching technique is used to pute frequency, rms value and initial phase angle of interharmonic. The proposed approach is easy to implement with high precision and good dynamic tracking feature, it suits to estimate harmonic/interharmonic parameters of voltage or current signals with discrete spectrum.3）It is known that flicker phenomena are closely related with harmonics and interharmonics, but at present, the detection methods of harmonics/interharmonics and flicker are pletely different. Based on deducing the equivalent relation of interharmonic and amplitude modulation wave to flicker, the detection methods of interharmonic and flicker are bined. Therefore, according to national and International Electrotechnical Commission (IEC) standard, a new flicker evaluation algorithm is presented based on interharmonic estimation. The algorithm can not only pute instantaneous visual acuity, shortterm flicker severity index and longterm flicker severity index, but also provide frequency and amplitude imformation of voltage fluctuation, thus, it benefits to analyze and manage voltage fluctuation and flicker. Furthermore, it provides a novel implemental model for flicker detection.4）To detect and locate nonsteadystate disturbances, digital image processing theory and image edge morphology detecting method are introduced. The outstanding features of the method are easy implementation, less puting plexity, high time resolution and low demand of sampling frequency, therefore, it can be used to effectively detect mon power disturbances such as voltage sag, swell, shorttime interruption, shorttime high frequency oscillatory, notching , etc.5）Deep analysis reveals that restrain background gradient is the key step for disturbing detection. Based on examining the origin of background gradient, two different methods for restrain background gradient are proposed. One uses TopHat morphology transform to restrain the background gradient produced by normal periodic alternation of analyzed signal, the other constructs suitable morphology filters to restrain the background gradient introduced by noises. Thus, the detecting sensitivity can be improved obviously.6）A new disturbing detection method based on order morphology and TopHat transform is then presented. It can not only restrain the background gradient produced by steady variation of analyzed signal, but also resist noises while keep the partial details of signal’s abrupt change. Therefore, it ensures the sensitivity and time locating precision of distrurbing detection. 7）An improved single phase voltage sag dececting algorithm is put forward. A new matrix, which is designed to decrease the phase delay that is unavoidable in traditional fictitious three phase systems, is constructed. The improved algorithm can almost instantaneously quantify the magnitude, duration and angel jump for voltage sag in single phase systems. Since ‘a(chǎn)bnormal variation’ phenomenon presents in the detecting process, a corresponding solving measure is carried out based on morphology calculation.8）As to three phase unbalanced voltage sag, an improved detection method is also presented. After carrying out positive and negative dq transform, morphology low pass filter which possesses the superiority of high accuracy and fast dynamic performance pared with traditional Butterworth filter is used to obtain positivesequence fundamental ponent and negativesequence fundamental ponent, and the zerosequence ponent is obtained by using improved single phase voltage sag detection method, then, voltage sag characteristics can be got easily. The improved method can estimate the sag parameters with high accuracy in real time. Therefore, it is not only efficient for the realtime detection of voltage sag but also effective for the realtime voltage sag control and pensation in dynamic voltage restorers（DVRs）.The purpose of the dissertation is to form an arithmetic system that related to some main power quality problems. It will provide effective theorem basis and algorithms for power quality online detection and offline analysis. The validity of the proposed algorithms has verified by normorous simulations, and the algorithms have been successfully applied in the development of a practical device named ‘the VIbased Electric Parameter Measurement Device’. Key words: Power Quality。 Algorithm目 錄學(xué)位論文原創(chuàng)性聲明學(xué)位論文版權(quán)使用授權(quán)書 I摘 要 IIAbstract IV第1章 緒 論 1 課題研究的背景和意義 1 電能質(zhì)量及其主要指標(biāo)參數(shù) 2 電能質(zhì)量概述 2 電能質(zhì)量標(biāo)準(zhǔn) 2 電能質(zhì)量分類及主要指標(biāo)參數(shù) 3 電能質(zhì)量參數(shù)估計(jì)理論及算法 6 時(shí)域分析方法 6 頻域分析方法 7 時(shí)頻分析方法 8 其它分析方法 12 本文的研究內(nèi)容 13第2章 傳統(tǒng)電能質(zhì)量相關(guān)參數(shù)的估計(jì)算法 16 引言 16 基于STFT的工頻參數(shù)估計(jì)算法 16 短時(shí)傅里葉變換 16 算法原理 17 窗函數(shù)選擇 19 窗寬的自適應(yīng)優(yōu)化 22 基本電能質(zhì)量參數(shù)測(cè)量的實(shí)現(xiàn)及仿真 23 算法實(shí)現(xiàn)步驟 23 電壓偏差估計(jì) 23 頻率偏差估計(jì) 27 三相不平衡度 30 相角差及功率因數(shù) 31 小結(jié) 32第3章 諧波、間諧波及閃變的檢測(cè)算法 34 引言 34 諧波檢測(cè) 35 諧波實(shí)時(shí)檢測(cè)方法 35 低通濾波器的選擇 36 算法仿真分析 37 間諧波的檢測(cè)算法 40 算法原理及實(shí)現(xiàn) 40 算法仿真分析 41 閃變的檢測(cè) 42 電壓波動(dòng)與閃變 42 IEC閃變測(cè)量方法 43 間諧波與電壓波動(dòng)、閃變的關(guān)系 45 間諧波與電壓波動(dòng)調(diào)幅波對(duì)于閃變的等值關(guān)系 46 基于間諧波的閃變參數(shù)估計(jì) 47 算法仿真分析 50 小結(jié) 52第4章 基于圖像邊緣處理的暫態(tài)電能質(zhì)量擾動(dòng)檢測(cè) 53 引言 53 數(shù)學(xué)形態(tài)學(xué)及形態(tài)濾波器 54 數(shù)學(xué)形態(tài)學(xué)基本運(yùn)算 54 形態(tài)濾波器 56 基于圖像邊緣檢測(cè)方法的電能質(zhì)量擾動(dòng)檢測(cè) 56 基于數(shù)學(xué)形態(tài)學(xué)的圖像邊緣檢測(cè) 56 電力擾動(dòng)檢測(cè) 57 方法性能分析 59 擾動(dòng)檢測(cè)方法的改進(jìn) 63 TopHat變換及抑制背景梯度的機(jī)理 63 信號(hào)去噪的形態(tài)濾波器設(shè)計(jì) 64 改進(jìn)方法的實(shí)現(xiàn) 65 改進(jìn)方法性能分析 65 基于順序形態(tài)變換的電壓擾動(dòng)檢測(cè) 68 順序形態(tài)運(yùn)算 68 順序形態(tài)邊緣檢測(cè)算子及擾動(dòng)檢測(cè) 69 性能分析 70 小結(jié) 71第5章 電壓暫降特征參數(shù)的檢測(cè)