本文選題：汽輪機調速系統(tǒng) + 低頻振蕩　； 參考：《華北電力大學》2014年碩士論文

【摘要】：低頻振蕩嚴重影響電網運行的安全與穩(wěn)定性,根據負阻尼機理設計的電力系統(tǒng)穩(wěn)定器(PSS)能夠對低頻振蕩起到有效的抑制作用。然而一些電網即使加裝了PSS仍會出現功率振蕩現象,理論及實際表明原動機及其調節(jié)系統(tǒng)波動也會引發(fā)電力系統(tǒng)低頻振蕩。近年來,數字電液控制系統(tǒng)(DEH)的投入使汽輪機及其控制系統(tǒng)對低頻振蕩的影響更加顯著。 2011年,南方電網某發(fā)電廠汽輪機組進行一次調頻試驗時引起機組低頻功率振蕩,并導致500kV電網多條聯絡線發(fā)生低頻功率振蕩告警,嚴重影響了電網穩(wěn)定運行。根據電廠振蕩時的實際運行情況,建立了鍋爐、汽輪機、發(fā)電機、勵磁系統(tǒng)和調速系統(tǒng)的數學模型,引入了調速系統(tǒng)的上位控制系統(tǒng)——單元機組負荷控制系統(tǒng)(CCS).,在熱工控制模型的基礎上建立了適于電力系統(tǒng)動態(tài)分析的簡化CCS模型。根據所建立模型在PSCAD/EMTDC仿真軟件中搭建了仿真平臺并實現了低頻振蕩事件的重現。 對汽輪機調速系統(tǒng)的運行原理、控制方式以及各部分組成做出了詳盡的分析介紹。根據研究需要對系統(tǒng)模型進行了合理簡化,建立了電力系統(tǒng)結構框圖,利用阻尼轉矩法對不同控制方式下的調速系統(tǒng)阻尼特性進行了分析,指出調速系統(tǒng)參數設置不當會引發(fā)電網功率振蕩。根據電網運行要求,通過分析計算給出了保證系統(tǒng)穩(wěn)定運行的調速系統(tǒng)參數取值范圍。 調速系統(tǒng)作為一次調頻機構不僅會影響系統(tǒng)的動態(tài)穩(wěn)定性,還會影響系統(tǒng)的頻率特性,研究表明過于追求一次調頻性能會破壞系統(tǒng)動態(tài)穩(wěn)定。探討了電力系統(tǒng)一次調頻性能與電網動態(tài)穩(wěn)定性的協(xié)調優(yōu)化問題,采用新型的智能優(yōu)化算法對汽輪機及其調速系統(tǒng)參數進行了優(yōu)化,在保證一次調頻性能的同時保證了電網的動態(tài)穩(wěn)定性,時域仿真證明了結果的準確性。
[Abstract]:The low frequency oscillation seriously affects the safety and stability of the power network operation. The power system stabilizer (PSS) designed according to the negative damping mechanism can effectively suppress the low frequency oscillation. However, even if PSS is installed in some power networks, power oscillation will still occur. The theory and practice show that the fluctuation of prime mover and its regulating system will also cause low frequency oscillation of power system. In recent years, the input of Digital Electro-hydraulic Control system (DEH) has made the influence of steam turbine and its control system on low frequency oscillation more remarkable. During the primary frequency modulation test of steam turbine unit in a power plant of Southern Power Grid, the low frequency power oscillation of the unit is caused, and the alarm of low frequency power oscillation occurs in many tie lines of 500 kV power network, which seriously affects the stable operation of the power network. The mathematical models of boiler, steam turbine, generator, excitation system and speed regulating system are established according to the actual operation of power plant oscillation. The load control system of unit (CCS) is introduced in this paper. Based on the thermal control model, a simplified CCS model suitable for dynamic analysis of power system is established. According to the established model, a simulation platform is built in the PSCAD / EMTDC simulation software and the low frequency oscillation events are reproduced. The operation principle, control mode and composition of turbine speed regulating system are analyzed and introduced in detail. According to the need of the research, the system model is reasonably simplified, the power system structure block diagram is established, and the damping characteristics of the speed regulating system under different control modes are analyzed by using the damping torque method. It is pointed out that improper setting of parameters of speed regulating system will cause power oscillation in power grid. According to the operation requirements of the power system, the range of the parameters of the speed regulating system to ensure the stable operation of the system is given through analysis and calculation. As a primary frequency modulation mechanism, the speed regulation system will not only affect the dynamic stability of the system, but also affect the frequency characteristics of the system. The research shows that the pursuit of primary frequency modulation performance will destroy the dynamic stability of the system. This paper discusses the coordination optimization between the primary frequency modulation performance of power system and the dynamic stability of power network. The parameters of steam turbine and its governing system are optimized by a new intelligent optimization algorithm. The performance of primary frequency modulation is guaranteed and the dynamic stability of power network is guaranteed. The accuracy of the result is proved by time domain simulation.
【學位授予單位】：華北電力大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TM712

【參考文獻】

相關期刊論文 前4條

1 韓志勇;徐衍會;李志強;李瑩;武朝強;;汽輪機調速系統(tǒng)引起電力系統(tǒng)共振機理低頻振蕩擾動分析[J];陜西電力;2009年07期

2 韓志勇,賀仁睦,徐衍會;由汽輪機壓力脈動引發(fā)電力系統(tǒng)共振機理的低頻振蕩研究[J];中國電機工程學報;2005年21期

3 徐衍會;賀仁睦;韓志勇;;電力系統(tǒng)共振機理低頻振蕩擾動源分析[J];中國電機工程學報;2007年17期

4 李伯伙;;600MW超臨界直流鍋爐特點分析與運行控制[J];中國高新技術企業(yè);2009年14期

，

本文編號：2057256