Voltage sag compensation with dynamic voltage restorer by the time-maximized strategy

Dynamic voltage restorers have been examined to compensate voltage sags in distribution networks to avoid production losses, especially in the Premium Power Park(PPP). If the compensation strategy can be optimized to extend the compensation time as long as possible, then the application of DVR in power system can be more popular, and the intelligent level of the power grid can also be effectively improved. As a result, this paper proposed a time-maximized compensation strategy to achieve a maximum compensation time based on the energy-minimized compensation strategy. According to the formula of dc-link discharge, the calculating formula of optimum phase angle jump of load voltage is deduced, and the principle and characteristic of the compensation strategy are analyzed respectively for single-phase and three-phase system. Simulation and experimental results are presented to confirm the effectiveness of the proposed compensation strategy.