This paper study the design technique of 10KW Inverter-grade elevator emergency power supply system. In discharging, the input side(battery) voltage is 250V at least and this is boosted by 680V to transform 3-phase (380V/60Hz). In charging, the input side(3-phase) voltage is transformed into constant voltage(680V) and this is converted into battery voltage and charged. The battery was been using the lead storage battery. But, the battery uses the super capacitor to achieve high performance in paper. The inverter controller is made possible to optimize performance by using a double loop control system using a current controller and the voltage controller. The current controller is designed to enable the control of the error by selecting the dead-bit control method to have the most rapid response characteristic for a sampling time is reached to zero and the control voltage were selected to design approach has the under damping. Through mathematical modeling it demonstrated that the controller has reached the error to zero in exactly one sampling. Using the MATLAB computer simulation of the same design and physical model demonstrated the superiority of the responsiveness of the control system.