Effective Operation Method of the Voltage Sag Compensator with Controlled Gradational Voltage by Interdependent Use of Capacitor Energy on Different Phase of a Power Line

Abstract

This paper presents the effective operation method by interdependent use of capacitor energy on the new concept of voltage transient sag compensator. This compensator consists of the series connection inverter units, and each inverter unit generates a different output voltage by 2ⁿ times. Namely, in this system, the compensation energy is accumulated in each inverter unit's capacitor charged with different voltage by 2ⁿ times. The method proposed here, in any case of various levels of transient voltage sags on different phase of a power line, provides the effective use of capacitor energy of all these inverter units.