<span lang="EN-US">This paper proposes a gravitational search algorithm (GSA) to allocate the thyristor-controlled series compensator (TCSC) incorporation with the issue of reactive power management. The aim of using TCSC units in this study is to minimize active and reactive power losses. Reserve beyond the thermal border, enhance the voltage profile and increase transmission-lines flow while continuing the whole generation cost of the system a little increase compared with its single goal base case. The optimal power flow (OPF) described is a consideration for finding the best size and location of the TCSCs devices seeing techno-economic subjects for minimizing fuel cost of generation units and the costs of installing TCSCs devices. The GSA algorithm's high ability in solving the proposed multi-objective problem is tested on two 9 and 30 bus test systems. For each test system, four case studies are considered to represent both normal and emergency operating conditions. The proposed GSA method's simulation results show that GSA offers a practical and robust high-quality solution for the problem and improves system performance.</span>

Due to the great importance of reliable indicators in electrical operating systems in all its different parts, it has been considered the most important factors in the design and maintenance of the electrical system, especially during its operation. The main reason for attention to reliability indicators relates to interruptions in the power system that are provided to consumers. The introduction of reliable indicators to solving an economic load dispatch (ELD) issue increases the possibility of providing customers with a required load with the highest degree of reliability. The ELD issue has been solved with reliability indicators. This means that the ELD problem with reliability is combined into one problem called combined the economic load dispatch with reliability (CELDR). Solving the above problem lowers the fuel cost while increasing the reliability of the generators while preparing the required load. The exchange market algorithm (EMA), in this work, has been implemented in a system of 26 generating units to solve the CELDR issue.considering system reliability, inequality, and equality constraints. The results obtained show the direct effect of using reliability indicators in solving the above problem, where the best results were obtained using the EMA algorithm to solve the mentioned problem, compared to other algorithms.

This research aims to improve the steady-state performance of high-voltage power transmission lines, which is a significant challenge for the power system grid's safe and reliable operation. The research adopted Flexible Alternating Current Transmission System for electronic devices. The flexible alternating current transmission system technology will be used in this specific work as Thyristor-Controlled Series Compensators. Thyristor-controlled series compensator devices increase transmission systems' capacity and enhance the voltage profile by regulating transmission line reactance. Gravitational Search Algorithm is a meta-heuristic approach applied to find the optimum size and optimal location of thyristor-controlled series compensators in power systems. The gravitational search algorithm is used to solve the multi-objective and integrated optimum power flow problem in reactive energy management during normal and contingency operations. The results showed reduced voltage deviation, reduced active/reactive power losses, and increased transmission line reserves above thermal limits, in addition to reducing the installed cost and number of thyristor series compensators devices. The simulation part was created with MATLAB programming language and validated with MATPOWER software. Applied to IEEE 30 bus system and 400kV super high voltage grid system.

In electrical power systems, unexpected outage of transmission systems, sudden increase of loads, the exit of generators from service, and equipment failure, leads to a contingency occurring on one or several transmission lines. The loads must be within the specified state and the transmission lines should not exceed the thermal limits. One of the important methods used to alleviate the contingency and reduce the congestion lines by injected a Distributed Generation (DG) within an optimal siting and optimal sizing in the distribution network that achieves improvement of the voltage profile as well as leads to reduce the losses. First, to achieve the best goals in this paper that is determined contingency lines, an index has been used called (Active Power Flow Performance Index) (PIRPF) and an equation called (Line Flow Sensitivity Index) (LFSI) is used for finding the optimum site for Distributed Generation. Second, to determine the optimum size for distributed generators, the Genetic Algorithm (GA) is used. Also, this research was distinguished by choosing new sites and sizes according to the GA to obtain the best desired results. Finally, these methodologies were applied to the IEEE-30 bus ring network using the MATPOWER Version 6.0, 16-Dec-2016 program within MATLAP R2018a environment.

Reliability indices are always one of the most important factors in the  power systems.In this paper,the problem of the economic load dispatch(ELD) and the problem of economic emission load dispatch(CEELD) have been improved taking into account reliability indices.That is,the problem and reliability of ELD are proposed as  combined economic load dispatch reliability(CELDR) and the problem CEELD is suggested as (CEELDR).In solving CELDR and CEELDR problems,tried to use power generators in a very reliable way to save system load,as well as minimum fuel and emission costs.In this effort,the ELD of power plants is successfully implemented in a single system containing 6 generating units, taking into account the reliability and emissions of the system with and without system power loss,inequality and inequality constraints,and valve point effects using the exchange market algorithm(EMA).The results suggest that reliability indicators in ELD can be used to create greater reliability in providing consumers with uninterrupted power.