Electromagnetic Impact from Electric Propulsion on Aircraft
Typ
Examensarbete för masterexamen
Master's Thesis
Master's Thesis
Program
Electric power engineering (MPEPO), MSc
Publicerad
2024
Författare
Thomas, Roshan
Subramaniam Muthuramalingam, Bharathi
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
Abstract
This thesis investigates the Conducted Electro Magnetic Interference (EMI) characteristics of Direct Current (DC) power cables in electric aircraft systems, focusing on the behaviour of unshielded and shielded cables across a frequency range of 1 Hz to 10 MHz. The DC ripple current flowing from the battery to the inverter is modeled and quantified using Simulink. This ripple current is fed to the cable model in
COMSOL for analysis of cross-talk with a neighbouring cable. The study examines the impact of DC ripple currents and induced voltage in neighbouring cables due to electromagnetic coupling. Key findings include the calculation of the DC ripple current in the unshielded and shielded cases. Peak-Peak ripple of 140 A was seen in the unshielded cable and 230 A in the shielded case. Higher DC ripple currents are due to the complex interactions of induced currents within the shielding layer. These findings emphasize the critical need for considering high-frequency EMI effects in designing the DC power cable systems to ensure optimal performance and regulatory compliance. The cables exhibited significant conducted EMI at the inverter’s switching frequency of 25 kHz, reaching approximately 160 dBμA. The effectiveness of shielding and distance between the cables was studied by analyzing the effect on the victim cable placed 100 mm above the cable. Analysis indicated that the induced voltage was reduced in the victim cables as the power cables were brought closer to each other. Finally, the study indicated that the amount of induced voltage is reduced when shielded cables are used. Future work should involve practical testing to validate these simulation results and explore further mitigation strategies for both conducted and radiated emissions in electric aviation applications.
Beskrivning
Ämne/nyckelord
Keywords: EMI, DC power cables, conducted emissions, shielding effectiveness, COMSOL, DC ripple current, electric aircraft systems.