Abstract: In recent days, the major concern in distribution system is power quality. The power quality is affected by various factors of the electrical network. Power quality problems such as voltage and frequency variation, harmonic contents affect the performance of Distribution System. Such problem has to be compensated by using CPDs. The energy control in distribution system is discussed by using multi-functional dynamic voltage restorer (DVR) control strategy. For the protection of customers for sudden change in voltage DVR is used. To improve the transient response and to eliminate the steady state error in DVR response, the Posicast and P+Resonant controllers are used respectively. The innovation here is that the DVR acts as a virtual impedance with the main aim of protecting PCC voltage and limits the fault current by using Flux control method. The simulations are performed with two types of loads:1) a constant power load and 2) a motor load using MATLAB/SIMULINK software.

Keywords: Dynamic voltage restorer (DVR), emergency control, voltage sag, voltage swells.