ower transformers and steam turbines were the key drivers in the development of the AC power system paradigm at the dawn of the 20th century, characterized by huge synchronous generators feeding millions of passive loads through large interconnected systems, all of them supervised and controlled from a centralized energy management system (EMS). In the same way, thyristor valves and IGBTs, intr...

Today’s power systems are large networks of electrical energy sources and load components, connected over long distances mainly through alternating current (AC) transmission and distribution grids. This basic structure currently undergoes significant changes to ensure the stability, availability and sustainability of the future electrical energy infrastructure. As a result, power system operati...

Flexible ac transmission systems (FACTS) controllers, which can effectively enhance the loadability of the network by controlling the power flows, must be placed optimally due to their high cost. This paper proposes a mixed integer based non-linear programming approach for optimal location of UPFC for system loadability enhancement in competitive electricity markets. The method accounts for ac ...

This paper describes how multi-agent system technology can be used as the underpinning platform for voltage control in power systems. In this study, some FACTS (flexible AC transmission systems) devices are properly designed to coordinate their decisions and actions in order to provide a coordinated secondary voltage control mechanism based on multi-agent theory. Each device here is modeled as ...

Considering aging power system infrastructures in conjunction with increased electricity trading activities, there is a strong need for future investments in electricity grids. Technological progress has made available a number of different investment alternatives, ranging e.g. from “standard” reinforcements of existing transmission capacities to the installation of Flexible AC Transmission Sys...

This paper presents an Interior Pont Method (IPM) and Evolutionary Particle Swarm Optimization (EPSO) based hybrid method to solve optimal power flow in power system incorporating Flexible AC Transmission Systems (FACTS) such as Static Synchronous Series Compensator(SSSC) for security enhancement in the power systems. A fuzzy logic composite criteria based severity index is also used as an obje...

Unified power flow controller (UPFC) is one of the most important flexible AC transmission systems (FACTS) devices in power systems. It has many applications such as stability enhancement, power flow control, voltage support, etc. In this paper UPFC is used in order to control voltage. In this scope, UPFC is installed on a specified bus and the voltage of the proposed bus is controlled by using...

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...

Convex relaxations of the power flow equations and, in particular, the Semi-Definite Programming (SDP), Second-Order Cone (SOC), and Convex DistFlow (CDF) relaxations, have attracted significant interest in recent years. Thus far, studies of the CDF model and its connection to the other relaxations have been limited to power distribution systems, which omit several parameters necessary for mode...

Power systems exhibit various modes of oscillation due to interactions among system components. Many of the oscillations are due to synchronous machine rotors swinging relative to each other. Controllable Series Devices (CSD), i.e. series connected Flexible AC Transmission Systems (FACTS) devices, such as Unified Power Flow Controller (UPFC), Controllable Series Capacitor (CSC) and Quadrature B...