多电飞机电气负载引起的电磁干扰

多电飞机(MEA)电气系统越来越大量地采用电子变换器,使得电气系统内和系统间的电磁干扰(EMI)问题变得非常严重.基于MEA电气负载特性,将电气负载分为整流类、斩波类和逆变类,建模和仿真这3类主要电气负载在稳态和突加工作情况下的传导EMI电流,并对逆变类负载的EMI特性进行了实验验证.结果表明:负载对电源侧的EMI集中在电力电子器件开关频率及其倍频邻域;斩波环节后端连接的大功率电气负载的突加使电源线传导EMI特性发生明显变化,主要体现在幅度频谱极值所对应的频率上.研究结果对独立电气系统的EMI识别及滤波器设计具有指导意义.

Electromagnetic interference caused by electric load of more electric aircraft

As an increasing number of power electronic converters are used in the electrical system of more electric aircraft (MEA), electro-magnetic interference (EMI) problems are becoming more and more severe both within the electrical systems and between different systems. Based on the electrical load characteristics of MEA, electrical load was classified into rectification, chopping and inverter. The conduction EMI current of the three major electrical load during the stable operation and the load surge of electrical loads were studied by modeling and simulations. EMI characteristics caused by the inverter load obtained was verified by experiments. The research results show that the conducted EMI to the power line is concentrated in the switch frequency of the power electronic device and the multiple frequency or so; the step change of the high power electrical load after the Buck chopper circuit makes the conduction EMI characteristics change significantly, which reflected in the frequencies of local maximum of amplitude spectrum. The study results provide the guidance for the EMI identification and the filter design of an independent electrical system.