New switching approach for DVR using one cycle control method

چکیده مقاله

One of the effective devices to eliminate voltage disturbances of sensitive loads in distribution systems is dynamic voltage restorer (DVR). In previous studies, the sinusoidal pulse width modulation (SPWM) method has been used as a switching method for DVR. However, a new switching approach called ‘‘one cycle control” (OCC) is presented in this paper for a three-phase DVR which has higher performance in dynamic and steady state operations compared to SPWM and is also simple and fixed in frequency. Moreover, this approach has few uncomplicated steps which make it suitable for practical implementation. In this study, the ability of the proposed approach is evaluated on two different types of DVR. The first DVR has fictitious dc link. In the second DVR, a battery is used in dc link. The proposed method can improve power quality disturbances such as voltage sag, voltage swell, and flicker. The ability of operating under changing parameters of load can show the robustness of the proposed approach. The simulation results obtained by OCC in six case studies were compared to the results obtained using the PWM method, revealing the higher efficiency of OCC than the PWM method.