Series of blackouts encountered in recent years in power system have been occurred because either of voltage or angle instability or both together was not detected within time and progressive voltage or angle instability further degraded the system condition, because of increase in loading. This paper presents the real-time assessment methodology of voltage stability using Phasor Measurement Un...

The voltage instability phenomena occur in both transmission systems and distribution systems. The weakening of voltage stability level will limit the growth of load served by distribution companies. Voltage instability in power distribution systems could lead to voltage collapse and thus power blackouts. The integration of distributed generation (DG) in the distribution system has increased to...

This paper provides a novel hierarchical control for VSI-based microgrids. The advantage of the provided control scheme is to maintain the frequency and voltage stability and load sharing against large-signal disturbances. A hierarchical control, consisting of three levels, is described. A new control loop based on PI controller, is presented. The new control loop has a great impact on increasi...

Abstract: Voltage instability is a major threat for security of power systems. Preserving voltage security margin at a certain limit is a vital requirement for today’s power systems. Assessment of voltage security margin is a challenging task demanding sophisticated indices. In this paper, for the purpose of on line voltage security assessment a new index based on the correlation characteristic...

On-line voltage stability monitoring based on the local phasor measurements is a very active branch of voltage stability assessment presently. It can be divided into local bus measurements based methods and local branch measurements based methods. The latter can be classified into three versions. They are voltage stability indices based on the feasible solution region of quadratic equation of r...

Voltage-sensor (VS) domains cause the pore of voltage-gated ion channels to open and close in response to changes in transmembrane potential. Recent experimental studies suggest that VS domains are independent structural units. This independence is revealed dramatically by a voltage-dependent proton-selective channel (Hv), which has a sequence homologous to the VS domains of voltage-gated potas...