in the deregulated power systems, transmission congestion is one of the significant and main problems of the electrical networks which can cause incremental cost in the energy. this problem has resulted to new challenging issues in different parts of power systems which there was not in the traditional systems or at least had very little importance. transmission congestion happens when the maxi...

This paper presents a new composite index to analyze power system transient stability. Contingency ranking in power system transient stability is a complicated and time consuming task. To prevail over this difficulty, various indices are used. These indices are based on the concept of coherency, transient energy conversion between kinetic and potential energy and three dot products of the s...

in this paper, simultaneous placement of distributed generation, capacitor bank and protective devices are utilized to improve the efficiency of the distribution network. the objectives of the problem are reduction of active and reactive power losses, improvement of voltage profile and reliability indices and increasing distribution companies’ profit. the combination of firefly algorithm, parti...

in this paper, a novel neuro-fuzzy based method combined with a feature selection technique is proposed for online dynamic voltage stability status prediction of power system. this technique uses synchronized phasors measured by phasor measurement units (pmus) in a wide-area measurement system. in order to minimize the number of neuro-fuzzy inputs, training time and complication of neuro-fuzzy ...

This paper presents an analysis of the influence of distributed generation in the occurrence frequency of voltage sags in electrical networks. It shows how the system characterization regarding voltage sags can be affected by the presence of distributed generation. The analysis is performed by using the fault positions method with a program that was implemented in Matlab. Several case studies i...

This study presents optimal placement of voltage sag monitors based on new Sag Occurrence Index (SOI) which ensures observability even in case of monitor failure or line outages. Multiple solutions for optimal placement of voltage sag monitors for voltage sag detection have been obtained by genetic algorithm approach such that observability of the whole system is guaranteed. A new Sag Occurrenc...

Nowadays, the penetration of distributed generation (DG) in power networks takes special place worldwide and is increasing in developed countries. In order to improve voltage profile, stability, reduction of power losses etc, it is necessary that, this increasing of installation of DGs in distribution system should be done systematically. This paper introduces an optimal placement method in ord...

Wind turbine can be divided into two categories: fixed speed wind generators (FSWGs) and variable speed wind generators (VSWGs) . VSWGs’s bus can be dealt with as PV-bus or PQ-bus in power flow calculation because reactive power compensation can be performed. Dynamic optimal power flow (DOPF) in VSWGs integrated power system is a typical complex multi-constrained non-convex non-linear programmi...