Practical Boundary of Static Voltage Stability Region in Cut-set Complex Power Space of Power Systems

Abstract

This paper proposes to display the boundary of static voltage stability region (SVSR) in cut-set complex power space for large electrical power systems. Active and reactive power flows on the branches in the critical cut-set are utilized to construct cut-set complex power space. We discovered that the boundary of SVSR can be approximated by hyper-planes in cutset complex power space. The paper summarizes the computation procedure of calculating the coefficients of those hyper-planes. Displaying SVSR in cut-set space is convenient for operators to monitor power systems voltage stability margin. The hyper-planes description of SVSR boundary in cut-set space makes it very easy to analyze, assess and optimize power system operation. Studies on various IEEE test systems and EPRI 1000 bus power system show that this computation method can approximate the SVSR boundary within engineering accuracy requirement