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This study presents an innovative strategy for load frequency control (LFC) using a combination structure of tilt-derivative and tilt-integral gains to form a TD-TI controller. Furthermore, a new improved optimization technique, namely the quantum chaos game optimizer (QCGO) is applied to tune the gains of the proposed combination TD-TI controller in two-area interconnected hybrid power systems, while the effectiveness of the proposed QCGO is validated via a comparison of its performance with the traditional CGO and other optimizers when considering 23 bench functions. Correspondingly, the effectiveness of the proposed controller is validated by comparing its performance with other controllers, such as the proportional-integral-derivative (PID) controller based on different optimizers, the tilt-integral-derivative (TID) controller based on a CGO algorithm, and the TID controller based on a QCGO algorithm, where the effectiveness of the proposed TD-TI controller based on the QCGO algorithm is ensured using different load patterns (i.e., step load perturbation (SLP), series SLP, and random load variation (RLV)). Furthermore, the challenges of renewable energy penetration and communication time delay are considered to test the robustness of the proposed controller in achieving more system stability. In addition, the integration of electric vehicles as dispersed energy storage units in both areas has been considered to test their effectiveness in achieving power grid stability. The simulation results elucidate that the proposed TD-TI controller based on the QCGO controller can achieve more system stability under the different aforementioned challenges.

This article proposes an intelligent control strategy to enhance the frequency dynamic performance of interconnected multi-source power systems composing of thermal, hydro, and gas power plants and the high penetration level of wind energy. The proposed control strategy is based on a combination of fuzzy logic control with a proportional-integral-derivative (PID) controller to overcome the PID limitations during abnormal conditions. Moreover, a newly adopted optimization technique namely Arithmetic optimization algorithm (AOA) is proposed to fine-tune the proposed fuzzy-PID controller to overcome the disadvantages of conventional and heuristic optimization techniques (i.e., long time in estimating controller parameters-slow convergence curves). Furthermore, the effect of the high voltage direct current link is taken into account in the studied interconnected power system to eliminate the AC transmission disadvantages (i.e., frequent tripping during oscillations in large power systems–high level of fault current). The dynamic performance analysis confirms the superiority of the proposed fuzzy-PID controller based on the AOA compared to the fuzzy-PID controller based on a hybrid local unimodal sampling and teaching learning-based optimization (TLBO) in terms of minimum objective function value and overshoots and undershoots oscillation measurement. Also, the AOA’s proficiency has been verified over several other powerful optimization techniques, differential evolution, TLBO using the PID controller. Moreover, the simulation results ensure the effectiveness and robustness of the proposed fuzzy-PID controller using the AOA in achieving better performance under several contingencies, different load variations, the high penetration level of the wind power, and system uncertainties compared to other literature controllers adjusting by various optimization techniques.

The main purpose of this paper is allowing doubly fed induction generator wind farms (DFIG), which are connected to power system, to effectively participate in feeding electrical loads. The oscillation in power system is one of the challenges of the interconnection of wind farms to the grid. The model of DFIG contains several gains which need to be achieved with optimal values. This aim can be accomplished using an optimization algorithm in order to obtain the best performance. The multi-objective optimization algorithm is used to determine the optimal control system gains under several objectives. In this paper, a multi-objective genetic algorithm is applied to the DFIG model to determine the optimal values of the gains of DFIG control system. In order to point out the contribution of this work; the performance of optimized DFIG model is compared with the non-optimized model of DFIG. The results show that the optimized model of DFIG has better performance over the non-optimized DFIG model.

This paper describes an important topic regarding with stability of the electrical grid, it is the load frequency control (LFC) problem. At any interconnected-areas of power systems, LFC problem must be solved to ensure system stability without any disturbance. When the amount of generating power is insufficient to meet the electrical load needs, frequency deviation is appeared with instability in power system. Doubly fed induction generator (DFIG) has the ability to support the power system with an additional inertia by supplying it with an extra active power. The studied system in this paper is a two-area thermal-thermal power plants with different participation levels of DFIG at the first area. The exchanged power is flowing between neighboring areas in the studied system through a tie-line. The two power plants in each model are subjected to 2% load perturbations in each area. These load perturbations are applied for examining the ability of Grey Wolf Optimizer (GWO) to restore the stability of studied systems. The optimum performance of power system is achieved when DFIG participation level is high. All time domain simulation results are carried out using MATLAB (R2015a) program for investigating the effectiveness of this method.

This paper describes an important topic regarding with stability of the electrical grid, it is the load frequency control (LFC) problem. At any interconnected-areas of power systems, LFC problem must be solved to ensure system stability without any disturbance. When the amount of generating power is insufficient to meet the electrical load needs, frequency deviation is appeared with instability in power system. Doubly fed induction generator (DFIG) has the ability to support the power system with an additional inertia by supplying it with an extra active power. The studied system is a two-area thermal-thermal power plants with different participation level of DFIG at the first area. An exchanging power is flowing between neighboring areas in the studied system through a tie-line. The two power plants in each model are subjected to 2% load perturbations in each area. These load perturbations are applied for examining the ability of Sine Cosine Algorithm (SCA) technique to restore the stability of studied systems. when DFIG participation level is high, the optimum performance of power system is achieved. All time domain simulation results are carried out by MATLAB (R2015a) program for investigating the effectiveness of this method.

The wind farms based on doubly fed induction generators (DFIG) is the most famous type of wind farms interconnected electrical grids as a result of its features (variable-speed conversion system). The performance of DFIG is affected with the control parameters of DFIG. In this paper, the studied model is composed of two-area power system interconnected with DFIG wind farm. The two-area is consisting of conventional thermal/hydro power generation units. The thermal and hydro power plant are represented by traditional unit's blocks. The multi-objective algorithm technique is used to determine the optimal values of the parameters of the studied control system (thermal/hydro with DFIG). The optimal design of DFIG control system with thermal/hydro traditional units is studied. This method is used to enhance the load frequency control of the two-area power system interconnected with DFIG wind farm. All simulation results are investigated using MATLAB Simulink program. Simulation results show the ability of tuned gains existing in the studied system using MOGA technique to enhance the grid frequency deviation.

This paper studies the impact of the outer crowbar on three wind farms based on different types of wind turbines. The first wind farm is based on fixed speed wind turbines such as squirrel cage induction wind turbines (SCIG). The wind farm is based on variable speed wind turbines such as double fed induction generator (DFIG) wind turbines. The last wind farm is based on a combination of variable and fixed speed wind turbines (DFIG and SCIG), it is called a combined wind farm (CWF). The crowbar is a protection system used for limiting high induced current and increasing of the DC-link voltage of the converter also used for protecting the rotor's coil of the wind turbines generators. The performance of wind farm with and without crowbar is examined under three phase fault. MATLAB Simulink program used for extraction all results. The best performance and the best results are in the CWF with the outer crowbar.