利用开断模型分析引弧板对低压断路器电弧运动的影响

Influence of Different Arc Run-on End Tab on the Arc Movement Process of Low Voltage Circuit Breaker with Interruption Model

为了描述电弧在跑弧道上运动的动态过程,得出引弧板对低压断路器灭弧性能的影响规律,提出了一种基于开断模型的描述电弧在跑弧道(含引弧板)上运动全过程的分析方法。首先建立了一种基于多场耦合的对低压断路器开断过程进行仿真的方法,该方法通过对多体动力学仿真软件ADAMS进行二次开发,实现了开断过程中电路、电弧、气吹、电动斥力、复杂机械运动等多场域的相互耦合;然后以某带引弧板的低压断路器为分析对象,利用所提出的仿真方法,对电弧从起燃、运动、转移到熄灭的全过程进行了计算仿真,分析了不同引弧板形状对低压断路器开断性能的影响,并通过实验验证。计算与实验结果表明,钩状引弧板的弧形轮廓在迎着电弧运动方向上具有更大的接触面积,且弧角朝栅片方向弯曲符合电弧的整体运动趋势,有利于电弧在弧根转移后进一步进入灭弧栅片,从而减少触头的烧蚀和提升电弧进入栅片的效果。

To describe the dynamic process of electric arc on the arc run-on plate to yield the influencing law of the arc run-on end tab on the breaker interruption performance, an analysis strategy based on the interruption model of low voltage circuit breaker is proposed for arc movement on the arc runner with arc run-on end tab. Firstly, a multi-field coupled calculation model that enables to simulate the interruption process of low voltage circuit breaker is constructed. Secondly developing the multi-body dynamic simulation software ADAMS, a set of differential equations describing the coupling relations among electric circuit, magnetic field, puffer effect, complex mechanical movement and dynamic arc model are established. This model is used to simulate the arc movement process undergoing arc striking, moving, transferring and extinguishing. The influences of different structures of arc run-on end tabs on the interruption performance of low voltage circuit breaker are analyzed and verified by the tests. Both calculation and experiment results demonstrate that the hook-like arc run-on end tab has a larger contact area than the flat end tab towards the arc movement direction, that the arc angle of the hook-like end tab bends to the direction of splitter plates conforming to the overall movement trend of the electric arc, and the arc root on hook-like end tab is thus easier to jump onto the arc run-on plate than on the flat end tab to consequently decrease the contact erosion.