江西电网220kV同塔双回线不平衡问题研究

发布时间：2018-04-18 06:55

本文选题：220k + V同塔双回输电线路　；参考：《南昌大学》2017年硕士论文

【摘要】：随着我国经济建设的快速发展,电力需求量越来越大,电网已开始出现输送能力不足,输电走廊紧缺等一系列问题,尤其是在经济发达地区。因此,为了有效地利用土地,降低电力建设投资以及提高线路走廊单位面积的传输容量,使得越来越多的220k V同塔双回输电线路投入使用。虽然采用同塔双回输电线路输送电能具有较多的优点,但是其结构和运行特点给电力系统带来了一些新的问题。日前江西电网220k V某同塔双回输电线路出现了严重的三相电流不平衡现象,可能给江西电网的安全运行带来一定的影响,有必要对江西电网中出现的三相电流不平衡现象进行研究分析。本文首先对国内外研究三相不平衡问题的成果进行了介绍,并且对不平衡度计算理论进行了分析;然后在PSASP系统等值的基础上,对研究线路进行了ATP-EMTP仿真建模。后面的研究工作分为两个方面。一方面研究可能引起220k V同塔双回输电线路不平衡的具体原因,如:导线的换位和更换相序排列方式、杆塔、地线和弧垂等因素对三相电流不平衡度的影响;另一方面根据研究的具体原因,进一步提出改善不平衡问题的措施,对措施的实施效果进行仿真和评价,并将该措施应用到省内其它市供电公司中进一步验证其有效性。针对江西电网在220k V线路的三相电流不平衡现象,本文采用ATP-EMTP对江西电网220k V同塔双回输电线路进行建模,对线路的不平衡电流进行仿真计算,并与实测数据比较,找出了220k V电网产生不平衡电流的主要影响因素。通过对江西电网220k V同塔双回线不平衡问题的研究,可有效改善江西电网220k V线路的电流不平衡现象,也可为输电线路工程的设计提供必要的参考依据。
[Abstract]:With the rapid development of economic construction in China, the demand for electricity is increasing, and a series of problems, such as insufficient transmission capacity and shortage of transmission corridors, have appeared in the power grid, especially in economically developed areas.Therefore, in order to utilize land effectively, reduce the investment of electric power construction and increase the transmission capacity of corridor unit area, more and more 220kV double-circuit transmission lines are put into use.Although using the same tower double circuit transmission line to transmit electric energy has many advantages, its structure and operation characteristics bring some new problems to the power system.A few days ago, a 220kV double-circuit transmission line with the same tower in Jiangxi power grid had a serious phenomenon of three-phase current imbalance, which may have a certain impact on the safe operation of Jiangxi power grid.It is necessary to study and analyze the three-phase current imbalance in Jiangxi power grid.In this paper, the domestic and foreign research results of three-phase imbalance problem are introduced, and the calculation theory of imbalance degree is analyzed, and then the ATP-EMTP simulation modeling of the research circuit is carried out on the basis of PSASP system equivalence.The later research work is divided into two aspects.On the one hand, the specific reasons that may cause the unbalance of 220kV double-circuit transmission line with the same tower are studied, such as the way of transposition and phase sequence arrangement of conductor, the influence of pole tower, ground wire and sag on the unbalance of three-phase current;On the other hand, according to the specific reasons of the study, the paper puts forward further measures to improve the imbalance problem, simulates and evaluates the effect of the implementation of the measure, and applies the measure to other power supply companies in other cities in the province to further verify its effectiveness.Aiming at the unbalance of three-phase current in 220kV transmission line of Jiangxi power network, this paper uses ATP-EMTP to model the 220kV double-circuit transmission line of the same tower in Jiangxi power network, and simulates and calculates the unbalanced current of the transmission line, and compares it with the measured data.The main influencing factors of unbalanced current in 220 kV power network are found out.By studying the unbalance of 220kV double circuit line of the same tower in Jiangxi power network, the current imbalance phenomenon of 220kV transmission line in Jiangxi power grid can be effectively improved, and the necessary reference basis for the design of transmission line project can be provided.
【学位授予单位】：南昌大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM75

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