電壓是衡量電能質(zhì)量的重要指標(biāo),電壓是否穩(wěn)定對(duì)整個(gè)電力系統(tǒng)是否能夠安全可靠地運(yùn)行有重要的影響,系統(tǒng)電壓下降不僅會(huì)使電網(wǎng)面臨電壓崩潰,甚至發(fā)展為更為嚴(yán)重的大量停電事故。因此,為保證電網(wǎng)安全的運(yùn)行,盡量避免發(fā)生電壓失穩(wěn)事件,有必要對(duì)電力系統(tǒng)的電壓進(jìn)行穩(wěn)定性評(píng)估研究。過去電力行業(yè)在很大程度上依賴于傳統(tǒng)的電力流程來進(jìn)行電壓穩(wěn)定性的靜態(tài)分析,通過計(jì)算選定負(fù)載總線的P-V和Q-V曲線來確定穩(wěn)定性,這些曲線往往是通過常規(guī)模型生成的,但由于功率流存在分歧,不可能完全生成Q-V和P-V曲線,所以本文通過以下三點(diǎn)進(jìn)行評(píng)估:首先,確定大多數(shù)發(fā)電機(jī)或分支由于干擾而消耗更多的無功功率,基于模態(tài)的分析及其應(yīng)用來評(píng)估大容量電力系統(tǒng)的電壓穩(wěn)定性。其次,通過電力系統(tǒng)Jacobean矩陣的正負(fù)特征值來作為系統(tǒng)電壓穩(wěn)定性的指標(biāo),對(duì)于小干擾穩(wěn)態(tài)電力系統(tǒng),正特征值表明系統(tǒng)是穩(wěn)定的,而負(fù)特征值表明系統(tǒng)是不穩(wěn)定的。最小特征值表示系統(tǒng)與電壓不穩(wěn)定性的接近程度。最后,通過將特征值與每個(gè)總線的Q-V靈敏度相關(guān)聯(lián),更好地理解系統(tǒng)電壓穩(wěn)定性與簡化的Jacobean矩陣特征值之間的關(guān)系。減少的Jacobean矩陣可以作為對(duì)稱矩陣,因此如果所有特征...

【文章頁數(shù)】：72 頁

【學(xué)位級(jí)別】：碩士

【文章目錄】：
摘要
Abstract
Chapter 1 Introduction
    1.1 Background and Importance of Research
    1.2 Research status
    1.3 Thesis objectives and methodology
    1.4 The thesis organization
Chapter 2 Mathematical Modelling of P-V and Q-V Curves
    2.1 Power System Stability
    2.2 Power system voltage stability
    2.3 Classifications of voltage stability
    2.4 Various system aspects causes voltage instability
    2.5 Two bus system representation
    2.6 Determination of critical voltage and critical power
    2.7 Analysis and comments in Q-V curves
    2.8 Q-V Curves
Chapter 3 Voltage Stability Modal Analysis
    3.1 Load flow problem
        3.1.1 Bus classifications
        3.1.2 Bus Admittance Matrix
        3.1.3 Bus Loading Equations
        3.1.4 Calculation of Net Injected Power:
        3.1.5 Newton-Raphson Method
        3.1.6 Load Flow based Newton-Raphson Technique
    3.2 V-Q Sensitivity
    3.3 Modal Analysis
    3.4 Participation Factors
        3.4.1 Bus participation factor
        3.4.2 Branch participation factor
        3.4.3 Generator Participation Factor
Chapter 4 Simulation and Results Analysis
    4.1 Introduction
    4.1 Description for network would be studied
    4.2 Load flow voltages results for the buses of power system network
    4.3 Analysis of real case data by using static analysis
        4.3.1 P-V curves for all weak buses
        4.4.2 Q-V curves for all weak buses
    4.4 Analysis of real case data by using modal analysis
        4.4.1 Eigenvalues
        4.4.2 Bus participation factors
        4.4.3 Generators participation factors
        4.5.4 Branch Participation Factors
        4.4.5 V-Q sensitivity for all buses
Chapter 5 Conclusion and Recommendations
    5.1 Conclusion
    5.2 Work Recommendations
References
Appendixes
    Appendix A
    Appendix B
        B.1 Bus data
        B.2 Transmission lines data
        B.3 Generators data
        B.4 Load data
        B.5 Transformer data
Acknowledgements



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