电力系统关键断面的快速识别与输电极限分析

发布时间：2018-05-07 05:03

本文选题：关键断面 + 模糊聚类　；参考：《华北电力大学》2017年硕士论文

【摘要】：当前,随着国民用电的增加和经济的发展,电力系统的规模日趋庞大,电网结构和电力系统运行方式日趋复杂。相应的对电力系统安全运行的可靠性提出了更高的要求。对系统中的所有线路都进行重点监控是不现实的。关键断面是电力系统中的薄弱环节,很多严重的停电事故都是由关键断面上线路的连锁反应故障引起的。因此,对系统中的关键断面进行研究具有很强的现实意义。该领域的研究也是当下研究的热点之一。本文主要对关键断面的快速识别及其输电极限两方面的内容展开了研究。在现有的识别系统关键断面的算法中,模糊聚类法由于无需事先给定分类个数,可以有效避免人为因素的主观影响而得到了广泛的应用。论文所提断面识别方法主要分为初始断面的确定、候选关键断面的确定以及关键断面的确定三个步骤。在确定候选关键断面线路时,论文提出了“中转站”的概念,采用基于汽车接力模型的算法实现对包含某两条线路的最短回路的快速搜索,避免了复杂的矩阵运算。在确定关键断面时,论文定义并计算了考虑输电裕度和潮流增加的关键度指标。采用所提方法能够有效地避免漏选线路。以IEEE标准节点系统算例验证了所提算法的有效性。当关键断面中潮流较重的线路发生故障而被切除时,及时计算出断面的输电极限值能够为调度员在保证系统安全稳定的前提下,制定正确的控制措施提供有力的参考,从而充分利用已有的输电资源,避免过甩负荷、过切机组等。输电断面的有功潮流控制是实际电网运行中的重要预防控制手段,准确掌握关键断面的输电极限是调控断面潮流的前提。论文首先对关键断面N-1约束下的最大传输潮流进行了计算,并提出了基于广义发电分布因子(GGDF)定向控制提升断面输电极限的算法,该算法考虑了平衡机对断面潮流的控制,且无需保证总发电量为常数,更加符合实际工况。输电断面暂态稳定传输功率极限是衡量系统稳定性的重要指标。论文对断面的暂稳极限传输功率进行了研究,提出了断面暂稳极限传输功率计算算法。该算法以断面主导的系统暂态稳定裕度趋于临界值为目标,经过多次迭代直至由该断面主导的系统暂态稳定裕度接近临界值,此时断面的功率即为暂稳传输极限值。在IEEE39节点系统中证明了该算法的有效性。
[Abstract]:At present, with the increase of national power consumption and the development of economy, the scale of power system is becoming larger and larger, and the structure of power network and the operation mode of power system are becoming more and more complex. Accordingly, the reliability of power system safety operation has been put forward higher requirements. It is unrealistic to focus on monitoring all circuits in the system. The critical section is the weak link in the power system, and many serious power outages are caused by the chain reaction fault of the line on the key section. Therefore, it is of great practical significance to study the key sections of the system. The research in this field is also one of the hotspots of current research. In this paper, the fast identification of key sections and its transmission limit are studied. In the existing algorithms for identifying the key sections of the system fuzzy clustering method has been widely used because it can avoid the subjective influence of human factors effectively without giving the number of classification in advance. The method is divided into three steps: the determination of the initial section, the determination of the candidate key section and the determination of the key section. The concept of "transfer station" is proposed in this paper, and the algorithm based on vehicle relay model is used to quickly search the shortest circuit containing two circuits, thus avoiding the complex matrix operation. In order to determine the critical section, the critical index considering transmission margin and power flow increase is defined and calculated. The proposed method can effectively avoid missing circuit. The effectiveness of the proposed algorithm is verified by an example of IEEE standard node system. When the line with heavy power flow in the critical section is cut off, calculating the transmission limit of the section in time can provide a powerful reference for the dispatcher to formulate the correct control measures on the premise of ensuring the safety and stability of the system. In order to make full use of existing transmission resources, avoid overload rejection, over-cut units and so on. The active power flow control of transmission section is an important preventive control method in actual power network operation, and it is the premise of regulating section power flow to accurately grasp the transmission limit of key section. In this paper, the maximum transmission power flow under N-1 constraint on key sections is first calculated, and an algorithm for directional control of transmission limit of lifting section based on generalized generation distribution factor (GGDF) is proposed. The algorithm takes into account the control of cross-section power flow by balancer. There is no need to ensure that the total power generation is constant, more in line with the actual working conditions. Transmission power limit of transient stability of transmission section is an important index to measure system stability. In this paper, the transmissibility power of the transient stability limit of the section is studied, and the calculation algorithm of the transmissible power of the transient stability of the section is put forward. In this algorithm, the transient stability margin of the cross-section dominated system tends to the critical value, and the transient stability margin of the system dominated by the section is close to the critical value after several iterations. At this time, the power of the section is the transient stability transmission limit value. The effectiveness of the algorithm is proved in the IEEE39 node system.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM711

【参考文献】