Multifunctional Dynamic Voltage Restorer

Now a days, power quality is an important application. Sophisticated electronic equipments, variable speed drive having high efficiency, and power electronic controller, are used to improve power quality. Voltage sags are the most common power quality disturbance in the distribution system. It occurs due to the fault in the electrical network or by the starting of a large induction motor and this can be solved by using the custom power devices such as Dynamic Voltage Restorer (DVR). It is smaller in size, and provides fast dynamic response to the disturbance and also has lower cost. A multifunctional DVR is used here to improve the power quality with the help of Posicast and P+Resonant controllers to improve the transient response and eliminate the steady-state error. Simulation result shows the capability of the DVR to control the emergency conditions of the distribution systems