飞机28.5V直流环网汇流条保护研究

Research on Aircraft 28.5V Direct Current Ring Bus-Bar Protection

飞机电气设备使用不当,电机、电器、电线等电气设备的绝缘老化,受机械损伤或战斗损坏等原因,都有可能使电网线路发生短路或过载故障。在环形配电系统中,环网汇流条发生短路等故障将对飞机产生致命性危害,要提高配电系统的可靠性就要对环网汇流条进行保护,即在发生接地故障后能进行有效隔离。对于环网汇流条的保护,具体要求是故障时,故障区间保护装置不拒动,后备保护的装置不误动,为了满足以上要求,依靠EMTP对故障系统进行模拟,分析故障时系统中出现的变化量。根据故障情况下配电系统中出现的电流突变和电压跌落等变化设置保护整定值及启动判据,并依靠Matlab平台做相关的仿真试验。试验证明:新的保护方法能实现环网故障时自动隔离,确保飞机配电系统的安全性,对提高飞机配电的可靠性具有重要意义。

Due to operation error of electrical equipment, insulation and aging of motors, electrical appliances, wires and other electrical equipment, mechanical damage, combat damage and other reasons, power lines are likely to encounter short-circuit or overload fault. In the annular distribution system, bus bar short-circuit fault will do fatal harm to aircraft, to improve the reliability of distribution system we have to protect the ring bus bars, and effectively isolate the fault bus bar. Simulating the fault system relay on EMTP, analyzing the variation of fault can meet the requirements that protection devices do not refuse operating and backup protect devices do not acting error. According to inrush current and voltage drop of the fault system, we can set protection setting value and criterion of starting, and do related simulation test relying on Matlab. It proved that the new method can achieve automatic isolation of fault bus bar, ensures the safety of aircraft electrical power distribution system, and it has importance to improve aircraft power distribution reliability.