This paper deals with a feasible power loss analysis simulator which can actually estimate the power losses of switching mode power converters using IGBTs. The power loss analysis simulator proposed newly is based upon the feasible measured switching power loss data tables and v-i characteristics data tables of power semiconductor power devices; IGBT and diodes. The effectiveness of practical simulation technique, which can discuss power loss evaluations for three phase PWM inverter, is confirmed from the viewpoints of the newly proposed simulation and experimental results.