Investigation of common mode noise in electric propulsion system high voltage components in an electrified vehicle

Common mode (CM) and differential mode (DM) noises are two of the main considerations in designing high voltage (HV) components, particularly minimizing filter sizing, shielding structure of the cables, grounding layout for circuits and power stage components and finally orientation of magnetics and chokes. This paper will introduce CM noise and electromagnetic interference (EMI) related issues and design guidelines in designing power electronics for Traction Power Inverters. Power module baseplate and mechanical packaging, vehicle and cable shielding and routing of ground paths and their effects on CM noise and EMI together with bands of frequencies are discussed in this paper. Mechanical and packaging considerations are important to keep CM noise within specified limit and this will be shown with simulated and test results