Analysis and optimization of electromagnetic compatibility for electric vehicles

Due to the changes of energy storage sources, driving systems, vehicle control units, etc., the electromagnetic compatibility (EMC) of electric vehicles is facing greater challenges than that of conventional oil-fueled vehicles. On the one hand, the use of high-power and high-voltage electrical components will generate high electromagnetic interference (EMI) energies in actual operation. On the other hand, automotive electronics with high integration and sensitivity is more susceptible to EMI, which is directly related to the safety of vehicles. In this paper, the EMI mechanism and suppression measures of motor driving systems, charging systems and other low-voltage systems are investigated. The results show that the main sources of EMI in electric vehicles are the quick switching of power switches, the operation of motor windings and the issue of signal coupling between high voltage cables and low voltage cables, and the EMI can be suppressed effectively by shielding, filtering and optimization of system principles.