RMK片式膜电阻在真空下的过电特性研究

Overcurrent characteristics of RMK chip film resistor in vacuum

为了提高小卫星的供电效率,越来越多的微小卫星的电源使用集中二次供电方式。为防止单机产品电源短路后出现大电流,影响同一母线上其他单机,使用限流电阻替代熔断器已成为集中供电模式下单机供电安全的发展方向。文中将理论与试验相结合,在真空环境条件下,通过开展RMK片式膜电阻的过电应力试验,研究该类型小阻值电阻通过的电流超出额定值时的阻抗特性。结果表明,当片式膜电阻的过电流值为额定电流的6倍以上时,该大电流在1 s内可以使电阻从几欧姆的阻值急剧上升至几千欧姆,从而达到保护卫星供配电系统的目的。另外,降低产品短路大电流的过流时间,可以防止电路板严重烧毁,避免引起其他类型的二次故障。

In order to improve the power supply efficiency of small satellites,the way of centralized secondary power supply is applied to more and more micro satellites.As the occurrence of large current after short-circuit of single product can affect other single machines on the same bus,using current limiting resistors instead of fuses has become a development direction for the safety of single machine power supply in centralized power supply mode.In combination of theory and experiment,the impedance characteristics of small resistance resistor when the current passing through it exceeds the rated value are studied by conducting overcurrent stress tests on RMK chip film resistors under the vacuum environment conditions.The results show that when the over-current value of chip film resistor is more than 6 times of the rated current,the resistance can rise sharply from a few ohms to several thousand ohms within 1 s,so as to achieve the purpose of protecting the satellite power supply and distribution system.Reducing the over-current time of short-circuit high current can prevent serious burning of the circuit board and avoid causing other types of secondary faults.