This paper presents a procedure for voltage stability margin evaluation under line outage condition considering static voltage stability limit. The proposed methodology is carried out in three steps. The first step of the study mode consists of obtaining sensitivity relation which relate loadability margin with real and reactive power injections at buses. In step two line outage is simulated us...

Shunt capacitors are commonly used in distribution system for reactive power compensation. Different analytical, numerical programming, heuristic and artificial intelligent based techniques have been proposed in the literature for optimum shunt capacitor bank (SCB) placement. This paper will present a very detailed overview of optimum SCB placement techniques. Six different approaches of optimu...

Now-a-days, demand for electric power has shown steady but geographically uneven growth.The wheeling of the available energy through existing long ac lines to load centers has a certain upper limit due to stability considerations. Thermal limit is the major limit to be considered while increasing loadability of existing EHV long transmission lines. Thus, these lines cannot be loaded to their th...

This paper presents a newly developed approach to find the optimal location of distributed generations (DGs) to improve power system voltage stability margin and reduce losses incorporating the constraints. The loadability limit index is used to assess the static voltage stability security margin, which is associated with the point of voltage collapse limit. Based on this, a toolbox is develope...

One of the major causes of voltage instability is the reactive power limit of the system. Improving the system's reactive power handling capacity via Flexible AC transmission System (FACTS) devices is a remedy for prevention of voltage instability and hence voltage collapse. In this paper, the effects of SVC and STATCOM in Static Voltage Stability Margin Enhancement will be studied. AC and DC r...

This paper presents a simple method for estimation of additional load as a factor of the existing load that may be drawn before reaching the point of line maximum loadability of radial distribution system (RDS) with different realistic load models at different substation voltages. The proposed method involves a simple line loadability index (LLI) that gives a measure of the proximity of the pre...

in recent years, in iran and other countries the power systems are going to move toward creating a competition structure for selling and buying electrical energy. these changes and the numerous advantages of dgs have made more incentives to use these kinds of generators than before. therefore, it is necessary to study all aspects of dgs, such as size selection and optimal placement and impact o...

This paper presents the use of Flexible AC Transmission Systems (FACTS) for improving loadability of the system in deregulated electric power system.The optimallocation and parameter settingsof two types of FACTS devices have been investigated in this study. The Static Synchronous Series Compensator (SSSC) and Thyristor Controlled Series Compensation (TCSC) as two FACTS devices are considered i...

A grand challenge for power grid management lies in how to plan and operate with increasing penetration of distributed energy resources (DERs), such as solar photovoltaics and electric vehicles, which disturb the power grid stability. Existing approaches are unable to verify if a point is on a loadability boundary or characterize all loadability boundary points exactly. This inability leads to ...