Phase-locked loop topology based on a synchronous reference frame and sliding mode approach for DVR applications

Phase-Locked Loop (PLL) circuits capable of fast tracking the utility voltage have been used for an increased number of power system equipments. This paper presents a new PLL structure for three-phase power systems. The proposed structure uses a synchronous reference frame and a sliding mode approach to detect phase angle, frequency and amplitude of the system three-phase voltages. The use of the sliding mode approach allows having a fast and robust phase and frequency detection of the power system voltages. In order to verify the behavior of the proposed PLL structure several simulation results are presented. From the obtained results it is possible to verify that this system can be applied to equipments such as dynamic voltage restores.