振动加载下转换型密封电磁继电器的性能退化行为研究

Electrical Properties Degradation of Electromagnetic Relays at Vibration and Load

目的研究航空用继电器的失效机理。方法通过对电磁继电器进行振动与工作载荷单独施加以及二者综合加载情况下的试验方法及性能退化行为研究,实时监测继电器内部触点间接触电阻等性能参数的变化趋势,并对不同条件下触点表面的微观形貌进行对比分析。结果发现相比较工作载荷单独施加而言,振动应力的加入使得继电器的寿命大幅度降低,并使得触点表面呈现"雪花"一般的形貌。结论振动环境导致了触点之间电弧的变化,以及触点表面接触压力、接触面积和接触超程等,并通过燃弧时间和超程时间的变化趋势对其进行了验证。

Objective To research the failure mechanism of aviation sealed electromagnetic relays(EMR). Methods Test method and performance degradation behavior of electromagnetic relay under the conditions of vibration and working load applied separately and together were researched to monitor variation trend of each performance parameter such as contact resistance in the control relay and analyze the microstructure of the contact surface under different conditions. Results It was found that adding vibration stress reduced life of the relay dramatically compared with individual application of working load. Besides,adding vibration stress made the contact surface be of a 'snowflake' general appearance. Conclusion Variation environment leads to the change of arc between contacts, as well as pressure, contact surface and over travel time of contact surface. It is verified by variation laws about the over travel time and arcing time between two contacts of the relay.