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This paper presents secondary voltage control by extracting reactive power from renewable power technologies to control load buses voltage in a power system at different operating conditions. The study is performed on a 100% renewable 14-bus system. Active and reactive powers controls are considered based on grid codes of countries with high penetration levels of renewable energy technologies. A pilot bus is selected in order to implement the secondary voltage control. The selection is based on short-circuit calculation and sensitivity analysis. An optimal Proportional Integral Derivative (PID) voltage controller is designed using genetic algorithm. A comparison between system with and without secondary voltage control is presented in terms of voltage profile and total power losses. The optimal voltage magnitudes at busbars are calculated to achieve minimum power losses using optimal power flow. The optimal placement of Phasor Measurement Units (PMUs) is performed in order to measure the voltage magnitude of buses with minimum cost. Optimization and simulation processes are performed using DIgSILENT and MATLAB software applications.

Remote farms in Africa are cultivated lands planned for 100% sustainable energy and organic agriculture in the future. This paper presents the load frequency control of a two-area power system feeding those farms. The power system is supplied by renewable technologies and storage facilities only which are photovoltaics, biogas, biodiesel, solar thermal, battery storage and flywheel storage systems. Each of those facilities has 150-kW capacity. This paper presents a model for each renewable energy technology and energy storage facility. The frequency is controlled by using a novel non-linear fractional order proportional integral derivative control scheme (NFOPID). The novel scheme is compared to a non-linear PID controller (NPID), fractional order PID controller (FOPID), and conventional PID. The effect of the different degradation factors related to the communication infrastructure, such as the time delay and packet loss, are modeled and simulated to assess the controlled system performance. A new cost function is presented in this research. The four controllers are tuned by novel poor and rich optimization (PRO) algorithm at different operating conditions. PRO controller design is compared to other state of the art techniques in this paper. The results show that the PRO design for a novel NFOPID controller has a promising future in load frequency control considering communication delays and packet loss. The simulation and optimization are applied on MATLAB/SIMULINK 2017a environment.

The world is targeting fully renewable power generation by the middle of the century. Distributed generation is the way to increase the penetration level of renewable energies. This paper presents load frequency control of a hybrid tidal, wind, and wave microgrid to feed an isolated island. This research is a step towards 100% renewable energy communities in remote seas/oceans islands. The wave and tidal generation systems model are presented. The study presents load frequency control through three supplementary control strategies: conventional integrators, fractional order integrator, and non-linear fractional order integrator. All the controllers of the microgrid are designed by using a novel black widow optimization technique. The applied technique is compared to other existing state-of-the-art algorithms. The results show that the black widow non-linear fractional integrator has a better performance over other strategies. Coordination between the unloaded tidal system and blade pitch control of both wind and tidal systems are adopted in the microgrid to utilize the available reserve power for the frequency support. Simulation and optimization studies are performed using the MATLAB/SIMULINK 2017a software application.

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The world has a target of achieving 100% renewable energy by the end of the century. This paper presents a case study to establish a new floating photovoltaic park (FPV) in Egyptian dams. In Egypt, two hydroelectric dams, namely High Dam and Aswan Reservoir, together produce 2.65 GW in the Upper-Egypt region. The addition of 5 MW FPV for each dam is simulated using the Helioscope software application. A comparison between the performance of the dams with and without adding the FPV is presented in terms of the evaporation rate and total produced energy. A comparison between different types of FPV, namely polycrystalline, thin film and mono-crystalline in the two dams are also presented. The results show that installing FPV in the Egyptian dams will drive the dams to better performance in terms of carbon dioxide reduction, water-saving from reducing evaporation and increasing hydropower generation.

This paper proposes and provides the design steps of three robust output feedback controllers to control the frequency of Wind-Diesel-Hydro hybrid system. The first presents a centralized robust based H ∞ (CRH ∞ ) controller. The role of H ∞ is to minimize the disturbance effect on the system output. The effect of the LMI tuning variables of RH ∞ controller on the system dynamic performance is presented and discussed. The controllers are solved using the Linear Matrix Inequalities (LMI) technique and characterized by a similar size as the plant that may be of higher order and thus creates difficulty in implementation in large systems. The second presents decentralized robust based H ∞ for each unit (DRH ∞ ). The third is robust PID controllers which are ideally practical for industry and more appealing from an implementation point of view since its size is lower. The optimum parameters of the robust PID controllers are found through the optimization by a novel combination of RH ∞ control theories through the Genetic Algorithm (GA) technique. More specifically, the third robust PID controllers are proposed to achieve the same robust performance as decentralized (DRH ∞ ) controllers, respectively. All controllers are used as load frequency controllers to control the Wind-Diesel-Hydro hybrid system . Comparisons of the performance of the three robust output feedback controllers under diverse tests in different disturbances and variation in the plant parameters are carried out.