Mixed-signal power system emulator extension to solve unbalanced fault transient stability analysis

Abstract

Abstract-This paper presents the extension of a platform originally devoted to symmetrical transient stability analysis, into the domain of unbalanced faults. The aim of this solver is to increase the speed of dynamic stability assessment for power systems. It is based on an analog representation of the grid alongside dedicated digital resources for the simulation of the models of power network components. Using the symmetrical components theory, this platform can be adapted to handle unsymmetrical disturbances, such as single-phase-to-ground faults, and the tripping of single-phase circuit breakers.

Series Capacitor Compensated AC Filterless Flexible LCC HVDC With Enhanced Power Transfer Under Unbalanced Faults

“…2) Technical performance: The significant increase of active power transfer during unbalanced fault cannot be achieved with any of the existing method. This improvement is of significance to power system considering that around 95% of the faults in power systems are unbalanced faults [17] and most of the CFs are caused by unbalanced faults [5]. 3) Economic performance: The significant technical performance improvements are achieved with much lower voltage rating of controllable capacitors.…”

“…13 that for single-phase and double-phase faults, more active power can be transmitted with the proposed method at all levels of the voltage drop. Al-though the performance improvement with three-phase fault is not obvious, it is important to point out that unbalanced faults account for about 95% of the faults in the transmission systems, while three-phase faults are very rare in occurrence, accounting for only about 5% [17]. Moreover, most of the CFs are caused by unbalanced faults [5] where active power can be transmitted through the healthy phases.…”