Performance Evaluation of SMES System for Initial and Steady Voltage Sag Compensations

This paper presents a voltage sag compensator (VSC) integrated with a superconducting magnetic energy storage (SMES) device. Performance evaluations of the SMES-based VSC for the initial and steady voltage sag compensations in sensitive load are carried out in details. Effects of time delay in discharge response and initial voltage sag angle on the initial voltage sag compensation are discussed to clarify the transient SMES property. In addition, three definitions of voltage sag compensation time duration are introduced to evaluate the steady SMES property of short-time and long-time voltage sag compensation operations.