考虑变电站多因素影响的输电网风险评估

发布时间：2019-01-08 12:08

【摘要】：变电站作为电网中的关键环节,承担着从输电网到用户的供电任务,其可靠性直接影响到电网的安全稳定和供电的连续性。因此,在对输电网进行风险评估时,有必要考虑变电站与电网之间的相互影响。针对目前研究中的不足,本文围绕考虑变电站多因素影响的输电网风险评估方法开展研究。首先,梳理了变电站对输电网风险水平的多影响因素,将变电站对输电网的影响分为主接线、继电保护可靠性以及元件参数不确定性的影响,其中,变电站主接线影响主要包括站内主接线形式和站外进出线回路数的影响。同时,引入了联系数的相关理论,用以处理元件参数不确定性,并利用功能组分解方法建立了继电保护的隐性故障模型。其次,鉴于上述影响因素,本文基于非序贯蒙特卡洛模拟法,提出了一种考虑变电站多因素影响的输电网风险评估方法。为了反映变电站对输电网的多因素影响,提高风险评估的速度,该方法做出了以下改进:一是利用拉丁超立方抽样法提高蒙特卡洛模拟的速度和效率;二是考虑到元件参数的不确定性,提出一种基于极限场景集的蒙特卡洛模拟法,实现了对变电站内部元件和电网元件的分层抽样;三是采用Warshall算法对含变电站主接线的电网拓扑结构进行快速连通性分析。在此基础上,选用基于直流潮流的负荷削减优化模型以评估各个系统状态下的失负荷风险。最后,对IEEE-RTS79系统和广东某地区电网进行风险评估,得到了分别考虑变电站主接线、继电保护可靠性以及元件参数不确定性影响的输电网风险评估指标,对比分析了上述因素对电网风险水平的影响,同时,通过算例分析验证了本文所提方法的有效性和正确性。
[Abstract]:As a key link in the power network, substation undertakes the power supply task from transmission network to user, and its reliability directly affects the security and stability of power grid and the continuity of power supply. Therefore, it is necessary to consider the interaction between substation and power network in the risk assessment of transmission network. In view of the shortcomings of the present research, this paper focuses on the research of transmission network risk assessment method considering the multi-factor influence of substation. Firstly, the influence factors of substation on transmission network risk level are sorted out, and the influence of substation on transmission network is divided into main connection, relay protection reliability and element parameter uncertainty, among which, The influence of substation main connection includes the mode of main connection and the number of incoming and outgoing circuits. At the same time, the related theory of connection number is introduced to deal with the uncertainty of component parameters, and the hidden fault model of relay protection is established by the method of functional group decomposition. Secondly, in view of the above factors, based on the non-sequential Monte Carlo simulation method, a transmission network risk assessment method considering the influence of substation multi-factors is proposed in this paper. In order to reflect the multi-factor influence of substation on transmission network and improve the speed of risk assessment, the following improvements are made in this method: firstly, the speed and efficiency of Monte Carlo simulation are improved by using Latin hypercube sampling method; Secondly, considering the uncertainty of component parameters, a Monte Carlo simulation method based on limit scene set is proposed, which realizes stratified sampling of substation internal components and grid components. Thirdly, Warshall algorithm is used to analyze the fast connectivity of the power network topology with substation main connection. On this basis, the load reduction optimization model based on DC power flow is selected to evaluate the risk of load loss in each system state. Finally, the risk assessment indexes of IEEE-RTS79 system and Guangdong power network are obtained, which take into account the main connection of substation, the reliability of relay protection and the uncertainty of component parameters, respectively. The influence of the above factors on the power grid risk level is compared and analyzed. At the same time, the validity and correctness of the proposed method are verified by an example.
【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】：TM732

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