【作者】 黄凯；

【导师】 丁明；

【作者基本信息】 合肥工业大学 ， 电力系统及其自动化， 2002， 硕士

【摘要】 本文采用了非序贯蒙特卡罗仿真方法，提出了交直流混合系统概率稳定性评估的模型和算法，建立了完整的风险指标体系。具体工作如下： 1．完善了直流输电系统的建模和调节控制系统的仿真。在换流器准稳态模型的基础上考虑了直流系统的负序阻抗，能满足电压不对称条件下交直流混合系统计算的速度与精度要求。 2．完成了交直流混合系统的潮流和暂态稳定计算的建模和软件设计。能处理2阶到6阶的发电机模型和2种负荷模型。 3．建立了输电系统的各种故障模式的概率模型和仿真方法，如：线路开路、线路短路、母线短路、断路器接地、断路器拒分、断路器拒合、重合闸拒合、换相失败、3-4运行方式等。 4．能模拟电力系统的各种紧急控制措施，如低频/低压减载、各种切机、快速调整汽门、励磁控制、低电压限电流、直流线路重启动等。并讨论了各种紧急控制措施对交直流混合系统概率稳定性的影响。 5．建立了系统层、变电站层可靠性评估指标体系，如失稳概率、失稳次数、切负荷概率、切负荷功率、切机概率等。 6．以多个系统为例，验证了本文所述模型和算法的正确性和有效性；提出了进一步的研究方向。更多还原

【Abstract】 This paper focuses attention on the modeling as well as computer algorithms for PSA of hybrid AC/DC power system by the Non-sequential Monte-Carlo simulation . The following is the work reported in summary.1.Having consummated the models of HVDC systems and the emulation of control systems. This paper takes the negative impedance into consideration on the basis of QSS(Quasi Steady State Model) model of converter, and the results of computation can meet the need of speed and precision for a mixed AC/DC system when asymmetric faults happened.2.Having completed the modeling and software design of power flow computation and stability analysis for hybrid AC/DC power systems. The package can deal with three types of loads and generator models up to sixth orders.3.A simulation method and probabilistic modeling of transmission systems is built, which can deal with the different failure modes, such as the open circuit and short circuit of transmission lines, short circuit contingencies of bus frame, common-mode failure, correlated faults, grounding faults of breakers, fail to trip and false tripping of breakers , recloser failures commutation failure,3-4 operation mode etc.4. The proposed method can simulate many emergency control measures ,such as under frequency/under voltage load shedding ,generator shedding, fast valve control, excitation control ,VDCL,DC restart etc.5 This paper rebuilds a set of new risk indices on the basis of system level and substation levels, such as Loss Of Stability Probability ,Loss of Stability Frequency ,Dynamic Loss Of Load, Dynamic Loss Of Energy, Probability of Generator Shedding ,Mean Time to Unstable etc. We have investigated the effects of different ECMs statistically. It is demonstrated that ECMs may have positive or negative effects on the transient stability under different conditions.Several sample systems are used to verify the accuracy of modeling and the effectiveness of algorithm implementation . The computation results show that the work is fruitful and the software can meet the need of engineering and research.The research work is financially supported by the National Natural Science Foundation of China (NSFC) under the grant No.59977004, the Natural Science Foundation of Anhui Province under the grant No.00104421 and the Outstanding Teacher Projects financially supported by the Education Ministry of China.更多还原