Progress of Electromagnetic Compatibility Design for Unmanned Aerial Vehicles

Abstract

The electromagnetic environment of UAV system was studied, and three key elements of electromagnetic interference (EMI) are analyzed. The research status of electromagnetic characteristics of UAV system at home and abroad was summarized from numerical simulation of EMI, experimental test of EMI and design of electromagnetic compatibility (EMC). The main contents include the research on electromagnetic characteristics of airborne antenna, EMI of data link and its mechanism, electromagnetic characteristics of internal cables, electromagnetic radiation test, electromagnetic conduction test, system-level EMC design, etc. The key technical challenges faced by the research on EMC of unmanned aerial vehicles at home and abroad are pointed out. Research on Electromagnetic EnvironmentWhen UAV is flying, it is not only affected by electromagnetic environment caused by radiation of internal equipment, but also by external electromagnetic environment such as lightning, interference station, nuclear electromagnetic pulse and so on. The radio frequency radiation overlaps in space, time, frequency and energy with the different working environment of UAV. If these interference cannot be prevented reasonably, the performance of airborne equipment will be greatly affected [1,2]. These EMI will not only interfere with the normal work of the UAV electronic system, but also destroy the key components of the electronic equipment, resulting in the failure of the instrumentation or control system, which directly threatens flight safety.Electromagnetic environment refers to the sum of power or field interference in different frequency range and the kinds and states of various interference sources when the UAV is performing its mission [3]. The external electromagnetic environment of UAV can be divided into natural electromagnetic environment and man-made electromagnetic environment. Natural electromagnetic environment exists objectively, including lightning, static electricity and earth electromagnetic field; human-made electromagnetic environment is formed by human activities, including electromagnetic wave emission, receiving activities caused by wireless communication and additional electromagnetic fields generated by these activities. The internal electromagnetic environment of UAV mainly includes antenna feed system, electromechanical system and circuit system.

A Constant Voltage/Current CPT System With Lightweight Characteristics for the Unmanned Aerial Vehicle

“…According to formula (12), in constant current mode, when the system input is a voltage source and the system operating frequency is fixed, the output current is only related to the value of the T-type compensation network capacitance C 1 .…”

“…Wireless power transmission technology solutions could reduce the battery capacity requirements for UAVs, and extend their range, but they require constant voltage/current (CV/CC) charging and high offset tolerance [11] [12].…”

Unconsidered but influencing interference in unmanned aerial vehicle cabling system

“…However, the limited compartment space in UAVs poses a potential source of unwanted electromagnetic interference (EMI) [2]- [4]. Previous research has shown that 60% of EMI occurrences on aircraft are caused by electromagnetic interference coupled to UAV wiring systems [5]. Cable length has been identified as a major factor influencing the electromagnetic susceptibility of devices to EMI, both from internal and external sources [2], [6]- [9].…”