| Title |
Internal Model Control of UPS Inverter with Robustness of Calculation Time Delay and Parameter Variation |
| Authors |
박지호(Park, Jee-Ho) ; 계중읍(Keh, Joong-Eup) ; 김동완(Kim, Dong-Wan) ; 안영주(An, Young-Joo) ; 박한석(Park, Han-Seok) ; 우정인(Woo, Jung-In) |
| Keywords |
UPS inverter ; Internal model controller ; Second order deadbeat response ; Load current prediction |
| Abstract |
In this paper, a new fully digital current control method of UPS inverter, which is based on an internal model control, is proposed. In the proposed control system, overshoots and oscillations due to the computation time-delay are compensated by explicit incorporation of the time-delay in the current control loop transfer function. The internal model controller is adopted to a second order deadbeat reference-to-output response which means that its response reaches the reference in two sampling time including computational time-delays. That is, the average current of filter capacitor is been exactly equal to the reference current with a time lag of two sampling intervals. Therefore, this method has an essentially overshoot free reference-to-output response with a minimum possible rise time. The effectiveness of the proposed control system has been verified by the simulation and experimental respectively. From the simulation and experimental results, the proposed system is achieved the robust characteristics to the calculation time delay and parameter variation as well as very fast dynamic performance, thus it can be effectively applied to the power supply for the critical load. |