The collaborative simulation based on friendly interface is developing fast. This paper mainly discusses about EMC (Electromagnetic Compatibility) prediction and analysis by using interactive modeling of EMC analysis software based on CSCW. In this paper, potential EMI (Electromagnetic Interference) sources and detailed parameter value settings are given. This project is colossal and divided into several sub blocks. Through computer supported cooperative work, simulation results verify that CSCW helps people solve difficult issues to a large extent. Virtual computer demonstration shortens long development cycle, increases efficiency and lowers costs before railway traction converter is brought into manufacturing. However, present work finished is far from enough. With further application of CSCW, there will be a brighter future in electromagnetic analysis realm.