Using under-over voltage relay & DVR for power sys voltage disturbance

In this study DVR has been presented as a custom power device to increase the power quality. Additionally network disturbances are classified into transient events such as voltage sags swells and other events such as longer duration main failures harmonic voltage distortion and under/ over voltages. The analyzed data out of this work shows that DVR can solve sag swell voltage and compensate the variation of voltage in less than one minute which is desired. The conclusion of simulation results illustrates this fact that application of relay in voltage disturbances guarantees sensitive load protection. The usage limitation of DVR makes us to use relay as a main solution.