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This paper presents the analysis of different two-area automatic generation control (AGC) systems in presence of thyristor controlled phase shifter (TCPS) and aims to improve the dynamic response of the proposed AGC systems in terms of minimizing system oscillations. In this study, TCPS unit is used to change the relative phase angle between the system voltages; as a result, regulate the real power flow to mitigate the frequency oscillations. Also, the values of integral controller gain of each area as well as the gain constant of TCPS unit are optimized with implementing improved particle swarm optimization (IPSO) method and gravitational search algorithm (GSA). The results reported in this paper demonstrate that the oscillations of frequency in both areas and tie line power oscillations can be effectively damped out by the use of TCPS unit that is located in the tie line. Furthermore, it can be concluded that the positive impact of using TCPS on the dynamic response of AGC system strictly depends on the dynamic response of generator, turbine and governor of the system. Among the three studied cases, positive impact of using TCPS in hydro-hydro system which has more oscillatory nature is much better than that of thermal-thermal or thermal-hydro system. Moreover, comparative studies of GSA and IPSO techniques confirm the high performance and effectiveness of both proposed methods in finding the optimal values of the studied systems. [ABSTRACT FROM AUTHOR]

This paper utilizes a novel method that uses the application of GA/PSO techniques to find the optimal location of FACTS devices in order to enhance voltage stability through Optimal Power Flow (OPF). Three different types of FACTS devices, Thyristor Controlled Series Compensator (TCSC), Unified Power Flow Controller (UPFC) and Thyristor Controlled Phase Shifter (TCPS) are considered. While finding the optimal location of these three types of FACTS devices all of the operational and security constraints are satisfied. Simulations are performed on IEEE 30 bus test system and results are presented. [ABSTRACT FROM AUTHOR]

In this paper, optimal design of fuzzy logic controller for a static VAR compensator to enhance the damping of power system oscillations is investigated. This problem is formulated as an optimization problem, which is solved by particle swarm optimization algorithm. Particle swarm optimization technique is utilized to adjust the membership functions and scaling factors of input/output of fuzzy logic controller to achieve a good control performance. Also, a conventional fuzzy logic controller (with non optimal parameters) is introduced and responses of both controllers in terms of damping effect and settling time are compared. The results show the effectiveness of proposed fuzzy controllers to damp out the oscillations of single- machine infinite bus system under variable loading and fault conditions. Furthermore, the results have indicated that the performance of optimal fuzzy logic controller is better than that of the conventional fuzzy logic controller over a wide range of loading conditions and disturbances. [ABSTRACT FROM AUTHOR]

In Particle Swarm Optimization (PSO) algorithm, although taking an active role to guide particles moving toward optimal solution, the most-fit candidate does not have a guide itself and only moves along its velocity vector in every iteration. This may yield a noticeable number of agents converge into local optima if the guide (i.e. the most fit candidate) agent cannot explore the best solution. In this paper, an attempt is made to get the advantage of the Ant Colony Optimization (ACO) methodology to assist the PSO algorithm for choosing a proper guide for each particle. This will strengthen the PSO abilities for not getting involved in local optima. As a result, we present a promising new hybrid particle swarm optimization algorithm, called ACPSO. The capability of the presented algorithm to solve a nonlinear optimization problem is demonstrated using different case studies carried out for optimal reactive power procurement. The IEEE 14-bus and 118-bus systems are adopted for reactive power market simulation. The main objective of the market is to minimize total generation costs of reactive power and transmission losses at different voltage stability margins. Based on the GAMS modeling language and the CONOPT solver, solutions are obtained for different models using a conventional non-linear optimization technique. Compared with the solutions found by the GAMS, Genetic Algorithm (GA) and the original PSO, the proposed ACPSO algorithm can provide promising results in terms of robustness and overall efficiency when it is applied to the reactive power market. [ABSTRACT FROM AUTHOR]