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Away to decrease the costs of generation and improve the performance of the grid generator, solving the problem of OPF based on line congestion management. As the power flow equation is nonlinear, this paper has performed the PSO algorithm to solve the OPF problem. By considering two technique this paper has performed the PSO algorithm for improving the performance. The first technique is to use a chaos generator to prevent PSO particles from sticking to local minimum points and the second is to consider the GSF in the WPSO algorithm structure so that the power passing through network lines can be simultaneously calculated and real power flow. Finally, the result of  WPSO-GSF algorithm which includes the bus voltage values, line losses, injection power to b buses, power passing through lines, total generation cost, setting electricity prices in two ways, UMP or LMP, depending on filling line capacity and calculating generators' profits has carried out .and also, to check the accuracy of the algorithm, the proposed method has been tested on IEEE 14-BUS, 30-BUS, 57-BUS standard networks, the results which indicate an increase in the speed and accuracy of the WPSO-GSF algorithm compared to other methods in improving the OPF problem.

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Overcoming the problem of transmission lines or a region of the power system congestion is one of the important issues facing the operators. In the meantime, in addition to choosing the appropriate method to relief transmission line congestion, the process should be implemented with the aim of minimizing the imposed costs. In this article, in order to optimally control the transmission lines congestion, an integrated method including management of the production and demand side of the systems along with the use of the flexibility of multi-carrier energy systems (electricity, gas and heat) is presented. The congestion alleviation technique is analyzed in the two modes of independent operation of the power system and integrated operation of multi-carrier systems, and their results have been compared. Also, taking into consideration the scenario of transmission line congestion with the simultaneous outage of a power generation unit, the effect of energy storage in solving this problem has also been studied. The simulation of scenarios and the evaluation of the effectiveness of the proposed method have been implemented in a multi-carrier energy system including the IEEE 39 bus power system in combination with the Belgian 20-node gas network and several energy hubs. The evaluation of the obtained results shows a significant reduction in the congestion management costs in the mode of integrated operation with the rescheduling of generation and consumption compared to the independent operation of the power system. In addition, it was proved that the properly storage and discharge of all types of energy can be successful in order to optimize (at least 10%) the imposed costs.