摘 要:针对110 kV高压真空断路器弹簧操动机构总体方案设计的问题,阐述了分、合闸弹簧参数的确定方法.通过理论分析和比较,探讨了分闸弹簧及其放置位置和合闸弹簧参数对操动机构总体方案的影响.结果表明:在满足机构所要求的分闸特性的前提下,分闸弹簧宜放置在操动机构运动链的中间行程较大之处,放置方位应使弹簧力的作用方向与力作用点的速度方向在分闸的整个过程中都趋于一致.合闸弹簧则要按输出力特性曲线来设计其参数,且相应确定操动机构的数目.对110 kV真空断路器,采用三相双断口的操动机构设计较为适宜.
关键词:操动机构; 机构设计; 真空断路器; 高压电器; 弹簧
分类号:TH122 文献标识码:A
文章编号:1000-5889(2000)01-0036-05
A design method for the spring operated mechanisms of
high-voltage vacuum circuit breakers
TAN Rong
(Dept. of Mechano-Electronic Engineering,Gansu Univ. of Tech., Lanzhou 730050, China)
JIANG Qi
(Xi?an Jiaotong University, Xi?an 710049, China)
Abstract:Aiming the problem of master designs for the spring operated mechanisms of the 100 kV high-voltage vacuum circuit breakers, a determining method for spring parameters of switch opening and closing mechanisms is presented in this paper. By means of theoretical analysis and comparison, the influence of these parameters and the position of opening switch on master designs is introduced. The results show that under required condition of closing switch characteristics, it is more suitable that opening springs are laid up on the place where the working throw is bigger in the middle of movement chain of operating mechanisms; their direction and position should be properly selected so that the acting direction of spring force is basically in accord with the speed direction of force acting point during whole process of switch opening. It is necessary that the closing spring parameters are designed according to the characteristics curve of output force and the numbers of the spring operated mechanisms should be appropriately determined. it is suitable that the spring operated mechanisms of the three-phase circuit breakers with double contractors are used for the 110 kV vacuum circuit breakers.
Key words:operating mechanisms; mechanism design; vacuum circuit breakers; high-voltage electrical apparatus; spring▲
高压断路器是电力系统中重要的开关设备,担负着控制和保护电路的双重任务,其性能好坏是决定电力系统能否安全供电的重要因素之一.高压断路器品种繁多,不同的断路器在性能方面各有不同的优缺点.真空断路器由于采用了真空灭弧技术,并具有不污染环境、操动机构功率小、使用寿命长和安全可靠以及维护方便等优点,因而获得了迅速的发展.但纵观断路器的发展史,从应用范围来说,这种断路器主要是应用在中、低压方面,而将其应用在110 kV及以上电压等级电力系统中,尚有许多问题需要解决,其中操动机构的设计就是问题之一.本文将探讨这一设计的部分问题.
1 分、合闸弹簧及其放置位置对断路器总体方案设计的影响
真空断路器总体方案的确定,除了要确定真空灭弧室的相互位置外,更主要的是要确定选用几个操动机构,这取决于分、合闸弹簧的参数和放置位置.
1.1 分闸弹簧参数的确定
在设计机构时,要根据要求的分闸速度和分闸时间配置分闸弹簧.确定分闸弹簧参数的依据是机构要求的分闸特性曲线,即触头运动速度和位移之间的关系曲线.具体方法是:根据计算的分闸弹簧等效力结果,初选分闸弹簧.然后核算动触头的分闸速度,检查是否符合设计要求,即速度曲线是否满足机构要求的分闸特性曲线,平均分闸速度和分闸时间是否符合给定要求.如发现有较大的差异时,则应作适当的调整.有关的计算公式见文献[1].
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