In IGBT PWM inverter-induction motor system, the high dv/dt and di/dt due to the fast swishing of IGBT could bring serious EMI issues and common-mode voltage is a major source of adverse effects. This paper presents a technique for modeling and analysis of the conducted EMI noise. The noise model is investigated to get a full understanding of the EMI mechanism. The analysis and results proposed here can provide a guideline for future effectiveness of filtering schemes in numerical machine tools. Effective measures must be taken to suppress electromagnetic interference in order to ensure a reliable work of numerical control machine tools. Hopefully, the results given in the paper reduce the mystery and the cut-and-try process in filter design in numerical control machine tools. Finally, the EMI mitigation methods are expounded.