【摘要】：隨著“西電東送”發(fā)展戰(zhàn)略的逐步實(shí)施,大容量遠(yuǎn)距離輸電已經(jīng)成為我國電網(wǎng)的重要特征。為了提高長距離輸電線路的輸送能力,我國電網(wǎng)廣泛采用了串聯(lián)補(bǔ)償和高壓直流輸電技術(shù)。然而,由串聯(lián)補(bǔ)償和高壓直流輸電引起的次同步振蕩風(fēng)險成為電網(wǎng)安全穩(wěn)定運(yùn)行面臨的重要問題。本論文對交直流互聯(lián)電力系統(tǒng)次同步振蕩的建模與機(jī)理進(jìn)行了深入研究,主要工作包括： (1)提出了一種應(yīng)用于次同步振蕩分析的汽輪發(fā)電機(jī)組軸系扭振機(jī)械阻尼系數(shù)在線測量解耦計算的方法。揭示了并列運(yùn)行的同型機(jī)組發(fā)生次同步振蕩時存在的同相振蕩模式和反相振蕩模式現(xiàn)象,并闡明了反相振蕩模式的力矩耦合關(guān)系。在此基礎(chǔ)上,利用反相振蕩模式下汽輪發(fā)電機(jī)組與電網(wǎng)解耦的特性,提出了一種通過主動激發(fā)反相振蕩模式實(shí)現(xiàn)軸系扭振機(jī)械阻尼系數(shù)在線測量與解耦計算的方法。該方法具有嚴(yán)格的理論基礎(chǔ),且易于現(xiàn)場實(shí)施,并在實(shí)際系統(tǒng)中得到成功應(yīng)用,有效的解決了軸系扭振機(jī)械阻尼系數(shù)在線測量的難題。 (2)闡明了直流輸電系統(tǒng)逆變側(cè)故障引發(fā)汽輪發(fā)電機(jī)組次同步振蕩的原因,突破了原有僅認(rèn)為整流側(cè)故障才引發(fā)機(jī)組次同步振蕩的認(rèn)識。論文分析了由于逆變側(cè)交流系統(tǒng)擾動引起直流輸電系統(tǒng)換相失敗,進(jìn)一步導(dǎo)致整流側(cè)汽輪發(fā)電機(jī)組次同步振蕩的物理過程,理論分析結(jié)果與實(shí)際錄波數(shù)據(jù)一致,驗證了理論分析的正確性。 (3)完成了具有相近扭振頻率的多機(jī)系統(tǒng)的次同步振蕩機(jī)理和特性分析。揭示了在具有相近扭振頻率的多機(jī)系統(tǒng)中,同時存在機(jī)網(wǎng)振蕩模式和機(jī)組間振蕩模式,并分析對比了兩種不同振蕩模式的阻尼特征。分析了決定機(jī)組間振蕩模式幅值大小的因素及其對軸系扭振嚴(yán)重程度的影響。據(jù)此對在實(shí)際系統(tǒng)中發(fā)生的次同步振蕩現(xiàn)象給出了合理、清晰的解釋。 (4)實(shí)現(xiàn)了應(yīng)用于次同步振蕩仿真的軸系變機(jī)械阻尼建模方法。該方法將軸系扭振機(jī)械阻尼系數(shù)作為變量代入轉(zhuǎn)子運(yùn)動方程,實(shí)現(xiàn)了軸系扭振機(jī)械阻尼系數(shù)在仿真過程中可以連續(xù)變化的功能,并在實(shí)時數(shù)字仿真器RTDS上實(shí)現(xiàn)。實(shí)現(xiàn)了一種發(fā)電機(jī)轉(zhuǎn)速脈沖信號輸出建模方法。該方法可以模擬與實(shí)際現(xiàn)場經(jīng)由發(fā)電機(jī)軸系齒盤原理一樣的轉(zhuǎn)速脈沖輸出,并具有同樣的動態(tài)特性。進(jìn)一步針對某大型煤電基地經(jīng)交直流外送的次同步振蕩問題,建立仿真模型,并開展相關(guān)次同步振蕩機(jī)理與特性分析,分析結(jié)論與現(xiàn)場實(shí)際情況吻合。
[Abstract]:With the gradual implementation of the development strategy of "power transmission from west to east", large capacity and long distance transmission has become an important feature of power grid in China. In order to improve the transmission capacity of long distance transmission lines, series compensation and high voltage direct current (HVDC) transmission technology are widely used in Chinese power grids. However, the risk of sub-synchronous oscillation caused by series compensation and HVDC transmission has become an important problem in the safe and stable operation of power grid. In this paper, the modeling and mechanism of subsynchronous oscillation in AC / DC interconnected power system are studied. The main works are as follows: (1) A decoupling calculation method for on-line measurement of torsional vibration mechanical damping coefficient of turbogenerator shaft system is proposed. The phenomenon of in-phase oscillation mode and anti-phase oscillation mode when the sub-synchronous oscillation occurs in the parallel operation of the same type unit is revealed and the torque coupling relation of the reverse phase oscillation mode is clarified. On this basis, a method of on-line measurement and decoupling calculation of mechanical damping coefficient of torsional vibration of shafting is proposed by using the decoupling characteristic of turbine-generator set and power grid under inverse oscillation mode. The method has a strict theoretical foundation and is easy to be implemented on the spot, and it has been successfully applied in the practical system. The problem of on-line measurement of mechanical damping coefficient of shaft torsional vibration is effectively solved. (2) the cause of subsynchronous oscillation of turbogenerator set caused by inverter side fault of HVDC transmission system is explained. It breaks through the original understanding that only rectifier side fault causes unit sub-synchronous oscillation. The paper analyzes the physical process of the subsynchronous oscillation of the rectifier turbine-generator set caused by the commutation failure of the DC transmission system caused by the disturbance of the inverter side AC system. The theoretical analysis results are consistent with the actual recorded data. The correctness of the theoretical analysis is verified. (3) the sub-synchronous oscillation mechanism and characteristic analysis of multi-machine systems with similar torsional frequencies are completed. In the multi-machine system with similar torsional vibration frequency, there exists both the grid oscillation mode and the inter-unit oscillation mode, and the damping characteristics of the two different oscillation modes are analyzed and compared. The factors that determine the amplitude of oscillation mode between units and its influence on the severity of torsional vibration of shafting are analyzed. A reasonable and clear explanation is given for the phenomenon of sub-synchronous oscillation occurring in practical system. (4) the method of shafting variable mechanical damping modeling is realized for the simulation of sub-synchronous oscillation. In this method, the mechanical damping coefficient of shafting torsional vibration is substituted into the rotor equation of motion as a variable, and the function of continuous variation of mechanical damping coefficient of shafting torsional vibration is realized in the simulation process, and it is realized on the real-time digital simulator RTDS. A modeling method of generator speed pulse signal output is implemented. This method can simulate the same rotating speed pulse output as the actual field through the generator gear disk, and has the same dynamic characteristics. A simulation model is established to solve the sub-synchronous oscillation problem of a large coal power station through AC / DC transmission. The mechanism and characteristics of the sub-synchronous oscillation are analyzed. The analysis results are in agreement with the actual situation in the field.
【學(xué)位授予單位】：華北電力大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2014
【分類號】：TM721.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 張運(yùn)洲;白建華;;“十二五”電力規(guī)劃重大問題探析[J];能源技術(shù)經(jīng)濟(jì);2011年01期

2 王西田,于達(dá)仁,鮑文,蘇杰先;一種新型的次同步扭振測量方法[J];電力系統(tǒng)自動化;2000年17期

3 李立mg;洪潮;;貴廣二回直流輸電系統(tǒng)次同步振蕩問題分析[J];電力系統(tǒng)自動化;2007年07期

4 傅惟惠，孫德昌，駱遠(yuǎn)志，，黃家裕，朱云生，羅時年，史大軍;具有串聯(lián)補(bǔ)償?shù)拇笮碗娏ο到y(tǒng)中次同步諧振（SSR）的分析[J];電力系統(tǒng)自動化;1995年09期

5 吳俊勇,程時杰;具有直流輸電的電力系統(tǒng)次同步諧振的研究[J];電力系統(tǒng)自動化;1996年11期

6 呂世榮,劉曉鵬,郭強(qiáng),夏道止;次同步諧振分析中復(fù)轉(zhuǎn)矩系數(shù)與特征值之間的關(guān)系[J];電力系統(tǒng)自動化;1999年03期

7 呂世榮,劉曉鵬,郭強(qiáng),夏道止;含TCSC的電力系統(tǒng)次同步諧振的復(fù)轉(zhuǎn)矩系數(shù)分析法[J];電力系統(tǒng)自動化;1999年12期

8 倪以信,王艷春,陳壽蓀,張寶霖;多機(jī)系統(tǒng)HVDC引起的軸系扭振的掃頻——復(fù)數(shù)力矩系數(shù)分析[J];電力系統(tǒng)及其自動化學(xué)報;1991年02期

9 張恒濤;汽輪發(fā)電機(jī)組軸系扭轉(zhuǎn)振動的實(shí)測技術(shù)[J];動力工程;1992年03期

10 張文濤;次同步諧振問題及防止措施[J];電網(wǎng)技術(shù);1989年02期

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