Study of sag compensation with DVR

Voltage dip analysis is a complex stochastic issue, since it involves a large variety of random factors: type of short-circuits in the power system, location of faults, protective system performance and atmospheric discharges. Among all categories of electrical disturbances, the voltage dip (sag) and momentary interruption are the nemeses of the automated industrial process. The dynamic voltage restorer (DVR) is a static series compensator (SSC) suitable for protecting industrial plants against voltage dip. This paper presents results about comparative analysis of three compensation techniques like in-phase compensation method, pre-dip compensation method (also called voltage difference compensation), and phase advance compensation method. To validate the effectiveness of each method, several disturbance scenarios including supply voltage drop and power factor of the load were examined. In particular, the paper analyzes the effect on necessary active power and voltage injected.