ZN98型真空断路器弹簧操动机构机械动力学特性仿真研究

Simulation Research of Mechanical Dynamic Characteristics of Spring Operating Mechanism for Type ZN98 Vacuum Circuit Breaker

操动机构是高压断路器的核心元件,其性能优劣显著影响着高压断路器分合特性。然而断路器故障时有发生,其中又以机械故障类型最为常见。因此需要提前发现潜伏性机械故障,进一步提高断路器的可靠性。针对这一问题,文中以ZN98型真空断路器弹簧操动机构为研究对象,采用Adams动力学仿真软件,建立了ZN98断路器弹簧操动机构的机械动力学仿真模型。仿真分析了操动机构各零部件运动情况,对断路器合闸与分闸过程分别进行了分析。将仿真得到的机械动力学特性作为操动机构正常工况的参照,对弹簧应力松弛潜伏性故障条件下操动机构的机械动力学特性进行仿真研究,以期及时发现高压断路器操动机构的潜伏性故障,提高电力系统的运行可靠性。研究表明,合闸弹簧发生应力松弛故障时,操动机构运动速度减慢,合闸时间增加,甚至会导致合闸过程分闸弹簧储存能量不足,进而导致断路器后续分闸失败;分闸弹簧发生应力松弛故障时,动触头的运动速度不断降低,分闸完成时间不断增长,分闸后触头无法达到额定开距,导致分闸失败。

The operating mechanism is the core component of high⁃voltage circuit breaker,and its performance sig⁃nificantly affects the opening and closing characteristics of high⁃voltage circuit breaker.However,circuit breaker faults occur frequently,of which mechanical fault is the most common.It is therefore necessary to detect the latent mechanical failure in advance so to improve reliability of circuit breaker further.In view of this problem,the spring operating mechanism for type ZN98 vacuum circuit breaker is taken as the research object and the mechanical dy⁃namics simulation model of operating mechanism for type ZN98 vacuum circuit breaker is set up by using Adams dynamics software model.The movement of each part of the operating mechanism is simulated and analyzed,and the closing and opening processes of the circuit breaker are analyzed respectively.The mechanical dynamic characteris⁃tics obtained by simulation are taken as the reference of the normal working condition of the operating mechanism and the mechanical dynamic characteristics of the operating mechanism under the latent fault condition of spring stress relaxation are simulated and studied in order to discover the latent fault of the operating mechanism of the high⁃voltage circuit breaker in time and improve operation reliability of power system.The research shows that in case of stress relaxation fault in the closing spring,the speed of the operating mechanism slows down and the closing time in⁃creases,which even lead to the insufficient charging of the opening spring in the closing process,thus causing subse⁃quent opening operation of the circuit breaker unsuccessful.While,in case of stress relaxation fault in the opening spring,the speed of the moving contact decreases continuously and the completion time of the opening operation con⁃tinues to increase.The contact can not reach rated clearance after opening and cause opening operation unsuccessful.