Current control method for UPS mode transfer in energy storage system

Abstract

In this paper, the uninterruptible power supply(UPS) mode transfer method of three-phase energy storage system (ESS) using the silicon-controlled rectifier(SCR) is applied. In the three-phase ESS using the SCR, the three-phase grid is not blocked because each-phase has a difference of 120 degree. Therefore, the ESS needs the UPS transfer method which is blocking the three-phase grid at the same time when the grid fault occurs. So the UPS mode transfer method which is blocking the SCR by changing the direction of the power flow is applied. The applied UPS mode transfer method is verified by simulation results using the PSIM ver.9.1.4.