复合材料飞机接地回流网络网内压降分析

Voltage drop in composite aircraft grounding and current return network

为保证机载电气设备的正常运行,复合材料飞机机身需增设金属接地回流网络来满足机上电气系统的接地需求。针对复合材料飞机接地回流网络网内压降计算问题,采用基于导体的体积部分元等效电路方法,对安装在复合材料飞机上的接地回流网络进行建模,通过计算接地回流网络接地点间的阻抗及接地回路的电流分布,分析某型飞机28 VDC、115 VAC汇流条上部分配电单元负载在巡航工况下接地网内沿路径的电压降,并考虑了故障电流注入及构件间接触阻抗对接地回流网络网内压降的影响。通过建立简化模型对网内压降进行分析,所提出的网内压降计算方法及仿真计算结果可为复合材料飞机接地回流网络的设计安装、故障管理及电气保护系统设计等方面提供参考。

To ensure normal operation of onboard electrical equipment,a metal grounding and current return network should be added to the composite aircraft fuselage to meet the grounding requirements of the onboard electrical system.For calculation of the pressure drop in the composite aircraft grounding and current return network,the conductor-based volumetric partial element equivalent circuit method is used to model the grounding and current return network installed on the composite aircraft.We analyze the voltage drop of partial distribution unit loads which belong to 28 VDC,115 VAC bus along the path in the grounding grid under the cruising condition,and consider the influence of large fault current injection and contact impedance between components on the voltage drop of the grounding and current return network.The voltage drop in the network is analyzed by establishing a simplified model.The proposed calculation method and simulation calculation results of the voltage drop in the network can provide references for the design and installation of composite aircraft grounding and current return network,fault management and electrical protection system design.