A design optimization tool of motor drive power stage has been developed. Through analyzing and modeling three major blocks, including front-end harmonic filters, IGBT inverters, and EMI filters, in a general-purpose drive, optimization programs have been implemented by using genetic algorithm (GA) engine. The optimizer can be used as design tools for engineers who might not have deep insights of all aspects like thermal, electromagnetic, and PWM controls. Even experts can use the optimizer to quickly and conveniently search all possible designs, which would be impossible for manual calculations and simulations. The design results obtained from the optimizer have been implemented and tested, and the experimental results have verified the models and programs