Muralish.M, Alexandar beski.I,Ilankannan.S
The increasing competition in the market and the declining profits has made it pertinent for the industries to realize the significance of high-power quality. This is possible only by ensuring that uninterrupted flow of power is maintained at proper voltage levels. Electric utilities are looking for solutions to ensure high quality power supply to their customers, a lot of solutions have been developed, but this project tends look at the solving the problems by using custom power devices such as Nine switch power conditioner. Nine switch power conditioner (UPQC) appears to be an especially good solution in the current scenario. This work describes the techniques of correcting the supply voltage sag and voltage swell in a distributed system. At present, a wide range of very flexible controllers, which capitalize on newly available power electronics components, are emerging for custom power applications. Among these, the distribution static compensator and the dynamic voltage restorer are most effective devices, both of them based on the VSC principle. A Nine switch power conditioner (UPQC) injects a voltage in series with the system voltage and an inductor injects a current into the system to correct the voltage sag, swell and interruption.