One of the issues of reliable performance in the power grid is the existence of electromechanical oscillations between interconnected generators. The number of generators participating in each electromechanical oscillation mode and the frequency oscillation depends on the structure and function of the power grid. In this paper, to improve the transient nature of the network and damping electromechanical fluctuations, a decentralized robust adaptive control method based on dynamic programming has been used to design a stabilizing power system and a complementary static var compensator (SVC) controller. By applying a single line to ground fault in the network, the robustness of the designed control systems is demonstrated. Also, the simulation results of the method used in this paper are compared with controllers whose parameters are adjusted using the PSO algorithm. The simulation results show the superiority of the decentralized robust adaptive control method based on dynamic programming for the stabilizing design of the power system and the complementary SVC controller. The performance of the control method is tested using the IEEE 16-machine, 68-bus, 5-area is verified with time domain simulation. تفاصيل المقالة

In modern power networks, once the restructuring of production units is done, traditional power plants will operate as virtual power plants (VPPs), which are actually a collection of distributed generation (DG) units and energy storage systems (ESSs) that form an integrated power plant. Commercial VPPs can replace the current traditional power plants in the near future, because they have many advantages such as organizing distributed energy resources (DER) and hydrogen and electricity storage systems. Considering that energy management and planning of DER resources in VPP have challenging issues, therefore, thoughts such as changes in instantaneous power generation, consumption, energy price and availability of system components should be taken into consideration, so that simulations and future research with problems will not accompanied. Since microgrids have the ability to monitor and control real-time power in power grids, determining the number of DER resources in VPPs is deliberated essential in order to reduce planning costs. For this purpose, in this paper, the optimal sizing of DERs is done using speed particle swarm optimization (SPSO) algorithm. In proposed optimization algorithm, the coefficients c1 and c2 are not constant and is changing according to the number of iterations, which makes the search in the problem solving space more efficient and its convergence is improved by 26% compared to the traditional PSO algorithm. Consequently, the number and sizing of solar photovoltaic (PV), wind turbine (WT), fuel cell (FC), electrolyzer, hydrogen storage and battery resources in a 20-year time horizon will be achieved with the lowest cost. تفاصيل المقالة