【摘要】：大型水輪發(fā)電機(jī)勵(lì)磁繞組匝間短路故障影響電機(jī)的正常運(yùn)行，通過(guò)多回路法計(jì)算勵(lì)磁繞組匝間短路故障，得到故障前后電流的波形并分析其特征，根據(jù)定轉(zhuǎn)子電流的特征，為保護(hù)方案的選擇提供幫助。 本文以多回路法為基礎(chǔ)，通過(guò)計(jì)算出的氣隙磁導(dǎo)系數(shù)，計(jì)算出單個(gè)線圈的電感系數(shù)，依據(jù)繞組連接形式，，將單個(gè)線圈的電感系數(shù)疊加形成支路電感參數(shù)，經(jīng)過(guò)支路與回路間的變換，得到回路電感參數(shù)。勵(lì)磁繞組短路故障后，電感、電阻、電壓矩陣的維數(shù)都增加，需要重新計(jì)算參數(shù)。著重研究了大型水輪發(fā)電機(jī)勵(lì)磁繞組匝間短路故障的暫態(tài)過(guò)程，對(duì)電感矩陣中電感計(jì)算公式進(jìn)行了簡(jiǎn)單的描述，同時(shí)將飽和及齒槽效應(yīng)對(duì)電機(jī)的影響使用等效系數(shù)來(lái)調(diào)整。編寫(xiě)了比較通用的程序，對(duì)連網(wǎng)空載工況下的短路故障進(jìn)行了仿真，諧波分析得到定子電流中接近基波頻率的諧波次數(shù)幅值很大，故障特征明顯。對(duì)不同匝數(shù)的勵(lì)磁繞組短路故障進(jìn)行了仿真，通過(guò)對(duì)比分析可以得到故障前后電流的變化趨勢(shì)，結(jié)果與理論分析相符。小匝數(shù)的勵(lì)磁故障對(duì)電機(jī)影響不大，但故障擴(kuò)大后，將產(chǎn)生嚴(yán)重后果，針對(duì)小匝數(shù)的短路故障，找到其故障后的特征規(guī)律，為保護(hù)方案的組合提供依據(jù)和幫助。 另外簡(jiǎn)單介紹了在程序編寫(xiě)過(guò)程中容易出現(xiàn)的問(wèn)題和相應(yīng)的解決辦法，為微分方程的初值和步長(zhǎng)的選擇提供了一些參考。
[Abstract]:The inter-turn short-circuit fault of excitation windings of large hydrogenerator affects the normal operation of the motor. The inter-turn short-circuit fault of excitation winding is calculated by multi-loop method. The waveform of current before and after the fault is obtained and its characteristics are analyzed, according to the characteristics of stator and rotor current, To assist in the selection of protection programs. Based on the multi-loop method, the inductance coefficient of a single coil is calculated by calculating the air-gap magnetic conductivity coefficient. According to the form of winding connection, the inductance coefficient of a single coil is superimposed to form a branch inductance parameter. The inductance parameters of the circuit are obtained by the transformation between the branch and the loop. The dimensions of inductance, resistance and voltage matrix are all increased after the fault of excitation winding short circuit, so the parameters need to be recalculated. The transient process of inter-turn short-circuit fault in excitation windings of large hydrogenerator is studied emphatically. The formula of inductance calculation in inductance matrix is simply described. At the same time, the effect of saturation and slot effect on motor is adjusted by equivalent coefficient. A general program is written to simulate the short-circuit fault under the no-load condition. The harmonic analysis results show that the amplitude of harmonics close to the fundamental frequency in the stator current is very large and the fault characteristics are obvious. The short circuit fault of excitation windings with different turns is simulated, and the variation trend of current before and after fault can be obtained by comparison and analysis. The results are consistent with the theoretical analysis. The excitation fault of small turns has little influence on the motor, but after the fault is expanded, it will have serious consequences. In view of the short circuit fault of small turn, the characteristic rule after the fault is found, which provides the basis and help for the combination of protection scheme. In addition, it simply introduces the problems and corresponding solutions in the process of programming, and provides some references for the selection of initial value and step size of differential equation.
【學(xué)位授予單位】：哈爾濱理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：TM312

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 李夢(mèng)喬;水輪發(fā)電機(jī)定子疊繞組內(nèi)部故障的暫態(tài)分析[D];哈爾濱理工大學(xué);2015年

本文編號(hào)：2281631