الفهرس 
Chapter 1 IntroductionOnly 14 pages are availabe for public view
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Abstract
In the advanced system of interconnected power generation, it is significant to match the power generation with the consumer’s demand. Whereas the hard fluctuations of consumer’s demand make the power system frequency is susceptible to these fluctuations cause the frequency deviates from its predefined value particularly in the presence of renewable energy sources (RES). A significant frequency deviation increases the possibility of loading and susceptibility equipment, which poses a major threat to the stability of the power systems. Therefore, the secondary controller of load frequency control (LFC) or automatic generation control (AGC) is necessary to save nominal system frequency and nominal tie-line power within their estimated limits during any perturbations also keep the connected generators to be synchronized. This is accomplished using standard controllers. However, traditional controllers have significant drawbacks, such as being very slow to operate, being unconcerned with the inherent nonlinearities of different power system components and being difficult to determine the gain of the integrator setting based on changes in the operating point. Therefore, design a decent controller structure and tuning its gains using optimization techniques referred to soft computing-based controller is a key role to solve these issues. In this thesis, different control structures based a recent powerful optimizations technique have been designed. Initially, to attain the finest tuning of the controller, a powerful algorithm like water cycle algorithm based conventional PID controller (WCA: PID) has been designed for the Egyptian power system (EPS) and compared to traditional schemes like Genetic algorithm (GA) and particle swarm optimizer (PSO) under the same environment. The traditional EPS scheme is divided into three plants: reheat, non-reheat, and hydro-power system, with a nuclear power generation system (NPGS) in El-Dabaa site being proposed as a fourth plant for EPS future production. To improve the performance of the control system, recently, cascade control (CC) structure is one of the most effective controllers which can be appropriately utilized in control applications. The standard PID controller, tilt-integral-derivative (TID) controllers and their relevance are used extensively in engineering problems because of their reliability, straightforward design, etc. As a result, in this thesis, many CCs have been designed such as PD-PI and TD-TI CCs based Harris-hawks optimizer (HHO) and WCA, respectively, are applied at two common models, with many scenarios to demonstrate the suitability and efficacy of the proposed designs compared to recently published schemes.
Nowadays, renewable energy resources (RES) become a main resource in the power generation system. To achieve a more desired level of smooth and damp oscillations in power system transient responses and due to the changing environment of the nature for renewable resources, the controller structure becomes a challenge to attain the desired stability. Also, the non-linearity aspects, such as generation rate constraints (GRC), boiler dynamics (BD), and governor dead band (GDB) result in a larger oscillation magnitude and settling time. In this regard, a recent advancement is the formulation of fractional order controllers, which do not actually include the use of integer, i.e., 1.0, but any real number for integrator and differentiator orders. The fractional order (FO) controller has a stronger dynamic solution with excellent robustness to parameter instability and external disturbances. It also improves stability in the case of nonlinear processes. Therefore, HHO based FO-PD-PI CC has been applied at three-area thermal-thermal-wind power plants to accomplish more stability compared to the traditional PID controller. In addition to these controllers, fuzzy logic controller (FLC) is used many times for adjusting the frequency and tie-line power deviations. Finally, WCA-based fuzzy-FOPID CC has been applied to PV-thermal power plants to attain less oscillation magnitude and less settling time. Frequency and tie-line power responses of the interrelated areas have been compared based on peak-undershoot, peak-overshoot, and settling time.
All the above experiments are designed based integral time multiplied absolute error (ITAE) criterion, which enhances less settling time and reduces the magnitude of Undershoot and Overshoot of signals. The proposed techniques are compared to recently published schemes to reveal the effectiveness and the robustness of our schemes in all situations, such as high step load perturbations (SLP), uncertainties, random load pattern (RLP) test, and non-linearity aspects.