首先分析了多电飞机电环控系统中产生电磁干扰的主要来源,即三相脉宽调制(PWM)逆变器。根据三相PWM逆变器电路的工作原理和简化电路,分析得出产生电磁干扰的共模电流,同时将共模电流作为电环控系统电磁辐射模型的激励源,据此建立了多电飞机电环控系统电磁辐射发射的模型。继而采用三维电磁仿真软件CST来研究电环控系统对客舱内的电磁环境的影响以及对穿舱线缆的电磁耦合效应。研究结果表明,电环控系统产生的电磁干扰导致客机内电磁环境恶化,客舱内以及其他系统机箱内的干扰的电场强度增加和穿舱线缆上的感应电流增大。
The three-phase PWM inverter as the main electromagnetic interference source generated from more electric aircraft(MEA)electric environmental control system is analyzed. According to the working principle of the three-phase PWM inverter circuit and its simplified circuit,the common mode current causing the electromagnetic interference is obtained by analysis. The common mode current is taken as the excitation source of the electromagnetic radiation model for the electric environmental control system to establish the electromagnetic radiation emission model of the MEA electric environmental control system. The electric environmental control system influencing on the electromagnetic environment in the cabin and electromagnetic coupling effect of the cabin cable is studied with 3D electromagnetic simulation software CST. The research results show that the electromagnetic interference generated by electric environmental control system makes the electromagnetic environment deterioration within the aircraft,increase the electric field strength of the interference in the cabin and other system crates and induced current of the cabin cable.