Research on Coupling Measurement Method of Inverter in High Voltage Electric Drive System

Instead of combustion engine, electric drive becomes the main power source for pure electric and hybrid vehicles. For one thing, it's eco-friendly and economical. For another, it introduces nonnegligible electromagnetic interference that threaten the electromagnetic compatibility of the system. One way it affects is high-low coupling, where electromagnetic interference transfers from high voltage components to low voltage components by means of conduction and radiation. In R&D stage, high-low coupling attenuation need to be considered and evaluated. After system integration, measurement of high-low coupling need to be performed. In this paper, mechanism of high-low coupling is studied. Test method at both R&D stage and system integration stage is introduced. It will help engineers find the weak point of the system and provides suggestion for optimization.