【正文】
學(xué)科分類號(hào): 本科生畢業(yè)設(shè)計(jì)三相電壓型高功率因素PWM整流器研究摘 要隨著現(xiàn)代經(jīng)濟(jì)的飛速發(fā)展,人們對(duì)電能的需求量在不斷的增加,因而對(duì)電網(wǎng)的質(zhì)量提出了更高的要求。在傳統(tǒng)的電網(wǎng)中,為減少無(wú)功含量,一般采用相控或者是不控整流電路,但傳統(tǒng)的整流器給電網(wǎng)中注入了大量的諧波污染,因而對(duì)電網(wǎng)的污染也就更加明顯。除此之外,電網(wǎng)無(wú)功功率的污染,還會(huì)導(dǎo)致電能損失,電網(wǎng)故障以及給予用戶生命財(cái)產(chǎn)安全帶來(lái)的危害己經(jīng)不可以忽視,對(duì)此必須采取行之有效的措施來(lái)減少電網(wǎng)中諧波污染。在科技發(fā)展的今天,相控整流電路以及不控整流電路,已經(jīng)不能滿足現(xiàn)代電力發(fā)展的需求,無(wú)法更好的使如今電網(wǎng)處在高效工作狀態(tài),所以不得不被取代, PWM整流技術(shù)應(yīng)運(yùn)而生。PWM整流器己經(jīng)彌補(bǔ)了相控整流器或不控整流器功率因數(shù)低,能量只能單相流動(dòng),諧波污染嚴(yán)重等缺陷。取而代之的是PWM整流器可以實(shí)現(xiàn)能量的雙向流動(dòng),功率因數(shù)可以到達(dá)單位功率因數(shù),電路性能穩(wěn)定以及消除諧波污染等。PWM整流器是解決諧波污染最有效的方法之一。論文首先分析了功率因數(shù)問(wèn)題,諧波污染問(wèn)題,PWM整流器原理,PWM整流器控制手段,以及主電路拓?fù)浣Y(jié)構(gòu),系統(tǒng)的闡述了空間矢量控制方案,并將模糊控制引入空間矢量控制中,實(shí)現(xiàn)了模糊空間矢量控制。最后,對(duì)模糊空間矢量控制建立數(shù)學(xué)模型,并對(duì)仿真結(jié)果進(jìn)行總結(jié)和分析。結(jié)果表明,基于三相電壓型高功率因數(shù)PWM整流器,除了能夠?qū)崿F(xiàn)高功率因數(shù)外,還可以消除諧波,實(shí)現(xiàn)能量雙向流動(dòng),以及改善了整流器整體性能,滿足了消除電網(wǎng)諧波污染的要求。三相電壓型高功率因數(shù)PWM整流器已經(jīng)成為目前解決諧波污染的主要方法之一。關(guān)鍵詞:諧波污染,PWM整流器,SVPWM,功率因數(shù),模糊控制ABSTRACTAlong with the modem economic fast development,the people have more and more requirement for electricity energy,which makes the pollution in the net of electricity very severity.The past rectifier has not satisfied the modem need.Because of this pollution,the rate of electricity accident is going up,and also takes the danger into the life of people.So we must take some measures to resolve this problem.Based on the development of science and technology, PWM rectifier technique has been researched.In the past 20 years,there are some limitations for rectifier, for example,the power factor is low, and the pollution of harmonic elements is very severity and So on.But now PWM rectifier has overe these problems.For the PWM rectifier, the power factor is improved;it also can eliminate harmonic elements and reduce the switch frequency. Firstly, the dissertation discusses the problem of power factor, the principle of PWM rectifier, the control instrument of PWM rectifier, and the configuration of circuit.The modulation principle of the voltage space vector(SVPWM)and its digital realization method are analyzed too.Secondly,programming of control is described.111e programming mainly contains interrupt service routines,digital PI control algorithm,SVPWM modulation and keyboard and display program.Finally, a math former Was established for SVPWM.a(chǎn)nd summarize and discuss the result of emulator.Experimental results show that operation of the bidirectional PWM rectifier base on SVPWM modulation cannot only eliminate harmonic elements and improve power factor ,but also reduce the switch frequency.Research on the ThreePhase High Power Factor PWM Rectifier has been one of the most measures for harmonic pollution.Key Word: harmonic pollution,PWM rectifier, SVPWM,power factor, fuzzy control第1章緒論 1 1 1 1 3 3 4 4 7第2章 三相電壓型PWM整流器控制技術(shù)的分析 7 7 8 10 14 14 17 17 18 18 19 19 19 20 21 21第3章三相電壓型高功率因數(shù)PWM整流器硬件設(shè)計(jì) 22 22 23 24 24 25 25 25 26 26第4章三相電壓型高功率因數(shù)PWM整流器軟件設(shè)計(jì) 27 27 29 30 30 31 32第5章基于模糊控制的三相VSR系統(tǒng)的仿真 32 32 34第6章總結(jié)與展望 34 34 35致 謝 35參考文獻(xiàn) 36第1章緒論 近20年以來(lái),電力電子技術(shù)已經(jīng)得到了飛速的發(fā)展,并廣泛應(yīng)用到電力、工業(yè)冶金、通訊、家用電器、化學(xué)工業(yè)、煤炭等各領(lǐng)域。隨著應(yīng)用電力電子裝置的普及,電網(wǎng)中存在的諧波污染問(wèn)題逐漸嚴(yán)重。目前大多數(shù)的電力電子裝置都是通過(guò)整流器與電力網(wǎng)彼此連接。比較經(jīng)典的整流器是由晶閘管或者是二極管組成的非線性電路,但如上所述的電路存在以下幾方面的問(wèn)題:a)輸入電流諧波含量高。b)從電網(wǎng)吸取無(wú)功功率,輸入功率因數(shù)低。c)交流側(cè)電網(wǎng)電壓產(chǎn)生畸變。d)整流器效率低?,F(xiàn)代電力電子裝置已經(jīng)成為目前電網(wǎng)最主要的諧波源。傳統(tǒng)整流器因?qū)﹄娋W(wǎng)的污染,已成為電力公害。因此傳統(tǒng)整流器已經(jīng)無(wú)法滿足現(xiàn)代電力網(wǎng)的需要,整流技術(shù)也面臨前所未有的挑戰(zhàn)。在交流電路中,電壓與電流之間的相位差()的余弦被定義為功率因數(shù),用符號(hào)cos表示,在數(shù)值上,功率因數(shù)就是用有功功率除以視在功率所得到的比值,即cos=P/S。對(duì)于線性負(fù)載組成的電路,如果加的電壓是正弦的,產(chǎn)生的電流是正弦的。而功率因數(shù)在非線性負(fù)載的電路中,加上正弦電壓后,它所產(chǎn)生的電流不是正弦的。然而與網(wǎng)側(cè)電壓歸結(jié)為同一個(gè)頻率的周期信號(hào)。傅立葉級(jí)數(shù)分解如下: (11) 如上式,當(dāng)n=1時(shí),I值為基波電流的大小。