R. Hemmati, H. Koofigar, M. Ataei,
Volume 12, Issue 1 (4-2015)
Abstract
The nonlinear nature and model uncertainties in electric power system show the importance of designing a suitable controller to operate under different operating conditions. In this paper, the problem of designing controller for UPFC is carried out with two objectives of easy implementation and operation under different loading conditions. In this regard, model reference adaptive system is proposed for UPFC control and this MRAS is improved by using PSO method. Besides, in order to limitation of input signal and also robustness, the normalization technique is used. The performance of the proposed algorithm is studied under nominal and heavy loading conditions and simulation results are presented to show robust performance of the proposed method. Also, the results of the proposed algorithm are compared with a PI type controller which is tuned by using PSO. Simulation results show the ability and effectiveness of the proposed method in comparison with the classical method.
Dr. Javad Pourhossein,
Volume 19, Issue 1 (4-2022)
Abstract
In this paper, while dynamically evaluating the capabilities of Static Inter phase power controller (SIPC), its effect on the transient stability of a sample power system has been investigated, as well as a technique based on its discontinuous control has been presented to improve the stability of the system. The research method is based on the computational solution of the dynamic equations of the system, the repetition of the simulation stages, the calculation of the critical clearing time (CCT) and the determination of the peak overshoot generated in the rotor angles of the machines due to a symmetrical three-phase short-circuit fault. For this purpose, the system and the related device were simulated in the DIgSILENT software envierment and the research issues were followed by considering multiple scenarios. In this regard, first all the capabilities of the device were confirmed in the time domain, and then the transient stability limit of the system with and without it was investigated and compared, resulting in a relative decrease in the transient stability limit of the system. Finally, in order to apply the technique, the main control of the device was transferred to another control called transient control so that the transmitted power of accelerated machines can be maximized within the time interval after the fault clearing, which ultimately results in a relative improvement in the transient stability limit of the system.
