12 kV真空断路器永磁直线电机操动机构特性分析

Characteristic analysis of permanent magnet linear motor operating mechanism for 12 kV vacuum circuit breaker

为解决12 kV真空断路器(Vacuum Circuit Breaker,VCB)传统操动机构和旋转电机操动机构结构复杂、可靠性低、动作分散性大以及有槽直线电机操动机构定位力引起推力脉动、振动、噪声及速度控制退化等而导致其难以精确分、合闸的问题,提出无槽圆筒形永磁直线同步电机操动机构。根据12 kV真空断路器分、合闸特性要求,对无槽圆筒形永磁直线同步电机(Slotless Tubular Permanent Magnet Linear Synchronous Motor,STPMLSM)的结构和参数进行设计,推导出其数学模型。利用有限元法对该电机操动机构的静、动态特性进行仿真分析,得到启动过程中电磁推力与时间的关系,分合闸过程中断路器动触头行程与时间、速度与时间的关系。结果表明:所设计的电机操动机构结构参数能够满足断路器分合闸特性要求,且推力波动得到有效抑制,为各电压等级断路器采用此类电机操动机构提供可靠依据。

The traditional operating mechanism and the rotary motor operating mechanism take on complex structure, low reliability and large dispersion. The detent force of slot linear motor operating mechanism brings thrust pulsation, motor vibration and degradation of speed control. These factors lead to imprecise opening and closing of 12 kV Vacuum Circuit Breaker （VCB）. In order to solve problems mentioned above, the Slotless Tubular Permanent Magnet Linear Synchronous Motor （STPMLSM） operation mechanism is proposed. According to the opening and closing characteristics, the structure and the parameters of STPMLSM are designed, with its mathematical model derived. The static and dynamic characteristics of the motor are simulated and analyzed by finite element method. The relationship between the motor electromagnetic force and time is obtained during the starting process, and the relationships among the movable contact travel, the speed and time are acquired. The results show that the motor structure parameters which are designed in this paper can meet the requirements of the circuit breaker switching characteristics, effectively suppress the thrust pulsation, and provide reliable foundations for the motor operating mechanism used in various voltage levels.