【作者】 陈超；

【导师】 张勇军；

【作者基本信息】 华南理工大学 ， 电力系统及其自动化， 2011， 硕士

【摘要】 受端电网的安全稳定运行一直是国内外学者关注的焦点,世界范围内多起大停电事故表明有必要在受端电网安装动态无功补偿装置,进行动态无功电压支撑。由于并联电容器的出力跟电压的平方成正比,在发生事故时无功出力不但不能增加反而减少,起负作用,因此在电源建设受限制的情况下,开展受端电网动态无功电压支撑的研究,对保证受端电网的安全稳定运行具有重要意义。本文首先阐述了受端电网动态无功电压支撑规划研究的背景及重要意义,并指出受端电网存在电压稳定性问题,需要制定必要的措施来保证受端电网的安全。然后比较了静态无功补偿和动态无功补偿的区别,进而综述国内外对动态无功补偿优化建模的研究,包括动态无功补偿设备的作用、安装地点和模型研究等。本文引入风险理论来评估受端电网动态无功电压支撑规划,由于风险理论涉及两个基本因素:概率和后果,本文接着介绍了模糊数学的相关知识,分析气候对电力系统元件参数的影响并以影响线路的气候因素形成模糊集,通过聚类分析和相似度指标对模糊集进行处理,建立预测新投产的电力系统元件故障率模型,并对某实际电网新投产的线路的故障概率进行分析计算,解决评估模型中新投产线路的概率无法计算的问题,紧跟着分析受端电网故障后的状态情况和有可能造成的损失,包括状态分离和转移以及两者所产生的期望损失,合适的动态无功补偿方案能够减少故障后电网的损失,同时还分析了正常运行方事下安装动态无功补偿设备后带来的运行收益,基于以上分析建立动态无功电压支撑规划的优化模型,以年期望收益最大化为目标函数,并满足多种约束条件。该模型的计算是通过静态潮流计算和动态仿真分析相结合来求取结果的。最后选择某典型的受端电网,求取其新投产线路的故障概率,针对三种典型的故障情景分别进行计算分析,分别得到各自的补偿方案,最后通过故障集计算并综合比较求得适合该受端电网的动态无功补偿方案。算例验证了本模型的有效性和实用性,本文的研究成果对于推动我国受端电网开展动态无功电压支撑规划的研究工作具有重要的理论意义和工程实用价值。更多还原

【Abstract】 The operation security and stability of receiving end networks is the issue that the foreign and domestic scholars pay attention to. Several large-scale blackout disasters in the world indicate it is necessary to install dynamic reactive power compensators in the receiving end networks for the dynamic reactive power voltage support. The shunt capacitors act negatively during the transient course of voltage collapse and the construction of power plants in the receiving end networks is limited. Therefore, the research on dynamic reactive power voltage support of receiving end networks is so significance for the secure and stable operation.Firstly, the background and the significance of dynamic reactive power voltage support of receiving end networks are represented and there is voltage stability problem in receiving end networks, it needs to take some measures for the security. The difference between static reactive compensation and dynamic reactive compensation are compared, and the research status in dynamic reactive compensation field at home and abroad are discussed, including the effect, location and method.The risk theory is used here to evaluate the dynamic reactive voltage support plan. The risk theory consists of two basic factors: probability and severity. Therefore the relevant knowledge of fuzzy mathematics is presented, the effect of climate on original reliability of power system is analyzed, and the climate factors that affect reliability are considered as fuzzy elements. The fuzzy clustering and the similarity are proposed to deal with fuzzy elements and the model that used to predict the original reliability parameters of new component in power system is presented, solving the problem that the probability of new line can not calculate. Then the state of receiving end networks after contingency is analyzed. The annual risk loss consist of state separating risk costs and transferring risk costs and it can be reduced by the appropriate dynamic reactive voltage support. The operating profit of the dynamic reactive compensation under the normal operation is also analyzed. Based on previous work, a mathematical model of dynamic reactive power voltage support plan is presented in this paper, which objective is to maximize the yearly average profit of the state without and with additional dynamic voltage support for the power system and satisfying all sorts of constraints.Finally one typical receiving end networks is selected for the optimization calculation through the model. It is showed that the proposed models are practical and effective. The results in this paper have important theoretical meaning and potential value of practical application to the dynamic reactive voltage support plan of receiving end networks.更多还原