楚雄电网输电线路通流能力与输电容量实证分析

【作者】 施蔚青；

【导师】 束洪春； 廖晓峰；

【作者基本信息】 昆明理工大学 ， 水利工程， 2007， 硕士

【摘要】 用电量的迅速增长引发了线路输送容量扩容的问题，这在楚雄地区的输电运行工作中尤为突出。由于楚雄电网不满足N-1要求，在云南电网电量总体平衡的情况下，仍然对楚雄地区局部进行限电。要彻底解决该问题，必须完善电网结构。计划于2008年3月500kV和平变电站建立之后，楚雄电网可以增加多回电源进线。在此之前，短时提高现有导线的输送容量，具有明显的社会效益和经济效益。本文从楚雄电网现有结构出发，分析了N-1存在的原因。对各种解决方案作了分析比较，提高运行允许温度的方案以投资小、线路改造停电时间短等优点成为解决线路扩容问题的有效方法。提高导线运行允许温度后，会对接续金具发热和导线机械强度带来影响，直接关系到线路的安全运行。本文引用国电电力建设研究所与北京电力公司合作获得的试验研究成果，并参考国外对该问题的分析结论，提出了合理的运行温度值。本课题通过借鉴华东电网在500kV输电线路所做的工程实践，得出提高导线载流量以后导线弧垂的变化值，结合楚雄电网进行了具有针对性的线路的实际观测，在总结试验和现场观测数据基础上，通过分析提出了通过提高导线运行允许温度后导线弧垂的控制范围。结合楚雄地区的地理气候条件，对《电力系统稳定导则》规定的输电电流数据进行了修正，提出了导线的持续允许电流值和短时允许电流值，对调度员的负荷控制进行定量指导。楚雄电网在采信本文结论的基础上，对提高线路输送容量作了技术和组织两方面的措施。一方面对220kV电源线路作了全线测量，保证导线的弧垂在可控范围。另一方面，加强了输电线路的维护，防范各种危害的发生。同时严格二次部分的工作，力争继电保护动作率保持100％。提高导线运行温度以后，满足了楚雄地区目前的负荷需求，导线运行情况良好。作为地区一级的供电企业，在全国首家作出了有益的尝试。在全国普遍存在有线路输送能力不足，热稳定问题突出的情况下，本文的结论，对其他类似情况都有借鉴意义。更多还原

【Abstract】 With the increasing of the load of ChuXiong bureau, problem on limit of lines transmission ability is more and more obvious. This paper studies the transmission capability of network transmission interface under steady state security restriction with N-1 principle. On how to solve the problem, several strategies are available to be choose.This paper discuses some problems of raising permissible operating temperature of conductor, and analyses technology of increasing current-carrying capacity of overhead conductors by raising their allowable temperature and its application to 220 kV lines.For improving the transmitting capacity of transmission line, the method of applying dynamic monitoring technology was presented after theoretical analysis, test and research in lab, and feasibility study based on field conditions.The transmitting capacity of 220kV transmission line in ChuXiong power grid is restricted by thermal equilibrium. To enlarge the transmitting capacity, the author theoretically analyze the feasibility of increasing conducting wire’s transmitting capacity by means of real-time monitoring the operation environment of conductors, and emphatically present the calculated conductor’s current capacity according to on-site measured parameters such as wind speed, ambient temperature, sunshine intensity, etc., and the simulation result of temperature rise of transmission line. Both the results from calculation and simulation show that by use of on-site measured environment parameters of transmission line the real-time determination of conductor’s transmitting limit is feasible, generally the transmitting capacity of transmission line can be increased in the range 10 percent to 30 percent.Lines’ curve is one of the important factors impacting the safe running of transmission line. The mathematical relationships between span variation and line stress are analyzed.Chuxiong administration of power supply had done the following methods to improving transmission ability of 220 kV power network. For example, engineering technologies and measures for improving the transmitting capability of 220kv transmission lines, improving professional management of lines by using technological progress, feasibility study of real-time dynamic capacity-increase for transmission lines.Half year Operation of Transmission Line in Chuxiong Electric Power Bureau approved that the lines work well. As the first one to have this taste in area bureaus, the result benefits the related situations a lot.更多还原