28 research outputs found

    Load Frequency Control for Hydropower Plants using PID Controller

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    Many development republics began to get rid of conventional energy and towards to use renewable energy like hydropower system, solar cells and wind turbines as soon as possible. Load Frequency Control (LFC) problem is coming to be the main topics for mentioning schemes due to not corresponding between main power system inputs such as change load demand and change in speed turbine settings. This paper illustrates a selftuning control of hydropower system that suggested and confirmed under Automatic Generation Control (AGC) in power scheme. The suggested power system involves one single area. The suggested self-tuning control system is employed in performing the automatic generation control for load frequency control request and compared it with conventional control structure. The power system dynamic modeling has regularly built in several essential parameters which have a significant influence According to frequency limitation. The main problem with all controllers is an exaggerated reaction to minor errors, producing the system to oscillate. The output response results for hydropower system obviously proved the benefit of using maximum load demand by tuning PID controller. Whereas, tuning PID controller has got properly more rapid output response and minimal overshoot

    Load Frequency Control for Hydropower Plants using PID Controller

    Get PDF
    Many development republics began to get rid of conventional energy and towards to use renewable energy like hydropower system, solar cells and wind turbines as soon as possible. Load Frequency Control (LFC) problem is coming to be the main topics for mentioning schemes due to not corresponding between main power system inputs such as change load demand and change in speed turbine settings. This paper illustrates a selftuning control of hydropower system that suggested and confirmed under Automatic Generation Control (AGC) in power scheme. The suggested power system involves one single area. The suggested self-tuning control system is employed in performing the automatic generation control for load frequency control request and compared it with conventional control structure. The power system dynamic modeling has regularly built in several essential parameters which have a significant influence According to frequency limitation. The main problem with all controllers is an exaggerated reaction to minor errors, producing the system to oscillate. The output response results for hydropower system obviously proved the benefit of using maximum load demand by tuning PID controller. Whereas, tuning PID controller has got properly more rapid output response and minimal overshoot

    Operation of The Hybrid Energy Resources with Storage System Participation

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    This paper focused on the optimal operation of the hybrid energy resources in the off-grid state considering energy storage participation. The hybrid energy resources consist of wind turbine (WT), photovoltaic (PV), diesel generator (DG), and energy storage system for supplying energy to DC and AC load demand with maximum reliability. The operation of the proposed energy system based on energy control and energy optimization is modeled. The energy optimization and energy control are implemented by heuristic and nonlinear quadratic programming approaches via optimal power flow on the resources side. The energy control is done based on the weight sum method in different operation states of the system. Also, the impact of the energy storage system on the hybrid energy resources is considered as backup resources. The energy control modeling is implemented via mathematical simulation and numerical analysis in the two operation states in the summer and winter seasons for verifying the proposed approaches. Finally, the results of the energy control show optimal states of the energy system in supplying demand with considering the energy storage system

    Operation of The Hybrid Energy Resources with Storage System Participation

    Get PDF
    This paper focused on the optimal operation of the hybrid energy resources in the off-grid state considering energy storage participation. The hybrid energy resources consist of wind turbine (WT), photovoltaic (PV), diesel generator (DG), and energy storage system for supplying energy to DC and AC load demand with maximum reliability. The operation of the proposed energy system based on energy control and energy optimization is modeled. The energy optimization and energy control are implemented by heuristic and nonlinear quadratic programming approaches via optimal power flow on the resources side. The energy control is done based on the weight sum method in different operation states of the system. Also, the impact of the energy storage system on the hybrid energy resources is considered as backup resources. The energy control modeling is implemented via mathematical simulation and numerical analysis in the two operation states in the summer and winter seasons for verifying the proposed approaches. Finally, the results of the energy control show optimal states of the energy system in supplying demand with considering the energy storage system

    Systematic review and meta-analysis of randomized, controlled trials on the effects of soy and soy products supplementation on serum adiponectin levels

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    "ackground and aims: Our aim in this meta-analysis was to determine the effect of soy and soy product supplementation on serum adiponectin levels. Method: A systematic search was conducted using Medline (PubMed and Web of Science), Scopus, and Cochrane Library for eligible trials up to August 2020. A random-effects model was used to pool calculated effect sizes. Results: Seven trials were included in the overall analysis. Our analysis showed that soy and soy product supplementation did not significantly affect adiponectin concentrations (WMD ¼ 0.77 mg/ml, 95% CI: 0.61, 2.15, P ¼ 0.27) in comparison with a placebo. The between-study heterogeneity was high (I2: 68.2%, P ¼ 0.004). Subgroup analysis, based on participants’ health status and duration of the supple- mentation, could not detect the potential source of the observed heterogeneity. In addition, subgroup analysis showed that the effect was not statistically significant in all subgroups. Conclusion: Overall, soy and soy product supplementation did not change the circulatory adiponectin levels. In addition, the results were not affected by the participant's health status and duration of sup- plementation. However, further studies are needed to confirm the present results

    Electrospun Ta-MOF/PEBA Nanohybrids and Their CH4 Adsorption Application

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    For the first time, biocompatible and biodegradable Ta-metal organic framework (MOF)/polyether block amide (PEBA) fibrous polymeric nanostructures were synthesized by ultrasonic and electrospinning routes in this study. The XRD peaks of products were wider, which is due to the significant effect of the ultrasonic and electrospinning methods on the final product. The adsorption/desorption behavior of the nanostructures is similar to that of the third type of isotherm series, which showed mesoporous behavior for the products. The sample has uniform morphology without any evidence of agglomeration. Since the adsorption and trapping of gaseous pollutants are very important, the application of the final Ta-MOF/PEBA fibrous polymeric nanostructures was investigated for CH4 adsorption. In order to achieve the optimal conditions of experiments and also systematic studies of the parameters, fractional factorial design was used. The results showed that by selecting temperature 40°C, time duration 35 min, and pressure 3 bar, the CH4 gas adsorption rate was near 4 mmol/g. Ultrasonic and electrospinning routes as well as immobilization of Ta-MOF in the PEBA fibrous network affect the performance of the final products for CH4 gas adsorption

    Utilization of additive from waste products with gasoline fuel to operate spark ignition engine

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    Impacts of blending fusel oil with gasoline on fuel combustion have been investigated experimentally in the current research to evaluate engine performance improvement and exhaust emission. Tested fuel include F10, F20 (10% and 20% of fusel oil by volume) and pure gasoline as baseline fuel have been used to operate 4-cylinder SI engine at increasing engine speed and constant throttle valve of 45%. The present results reveal a shorter combustion duration and better engine performance with F10 over engine speeds with maximum value of 33.9% for the engine brake thermal efficiency. The lowest BSFC of 251 g/kW h was recorded at 3500 rpm engine speed also with F10. All blended fuel have almost similar COVIMEP. Less NOx emission was measured with F10 at 4500 engine speed compared to gasoline. However, CO emissions reduced while higher CO2 was observed with introducing fusel oil in the blend. Moreover, HC emission increased an average by 11% over speed range and the highest value was achieved with 10% fusel oil addition compared to 20% and pure gasoline. Accordingly, higher oxygen content of fusel oil and octane number contribute to improve combustion of fuel mixture. © 2022, The Author(s).King Saud University, KSUThis Project is funded by King Saud University, Riyadh, Saudi Arabia

    Synthesis of efficient cobalt–metal organic framework as reusable nanocatalyst in the synthesis of new 1,4-dihydropyridine derivatives with antioxidant activity

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    Efficient cobalt–metal organic framework (Co-MOF) was prepared via a controllable microwave-assisted reverse micelle synthesis route. The products were characterized by SEM image, N2 adsorption/desorption isotherm, FTIR spectrum, and TG analysis. Results showed that the products have small particle size distribution, homogenous morphology, significant surface area, and high thermal stability. The physicochemical properties of the final products were remarkable compared with other MOF samples. The newly synthesized nanostructures were used as recyclable catalysts in the synthesis of 1,4-dihydropyridine derivatives. After the confirmation of related structures, the antioxidant activity of derivatives based on the DPPH method was evaluated and the relationship between structures and antioxidant activity was observed. In addition to recyclability, the catalytic activity of Co-MOF studied in this research has remarkable effects on the synthesis of 1,4 dihydropyridine derivatives

    Synthesis of Bioactive Yttrium-Metal–Organic Framework as Efficient Nanocatalyst in Synthesis of Novel Pyrazolopyranopyrimidine Derivatives and Evaluation of Anticancer Activity

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    Novel Yttrium-metal–organic framework (Y-MOF) was synthesized under optimal conditions of microwave with a power of 20 W, the temperature of 30 degrees of centigrade, and time duration of 10 min. The products were characterized by SEM (morphology and size distribution), TGA (thermal stability), BET technique (surface area), and FTIR (characterization of the related group). The Yttrium-metal–organic framework (Y-MOF) synthesized in this study, after identifying and confirming the structure, was used as an efficient and recyclable catalyst in the synthesis of new pyrazolopyranopyrimidine derivatives. Following the study of the properties and applications of Y-MOF, its anticancer properties on breast cancer cells based on the MTT method were evaluated, and significant results were observed. In addition, the anticancer properties of the pyrazolopyranopyrimidine derivatives were investigated

    Optimization and control of hydro generation scheduling using hybrid firefly algorithm and particle swarm optimization techniques

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    The fundamental requirement of hydropower system scheduling is to determine the optimal amount of generated powers for the hydro unit of the system in the scheduling horizon of 1 year or few years while satisfying the constraints of the hydroelectric system. Annual hydro generation scheduling (AHGS) is a complicated non-linear, non-convex and non-smooth optimization problem with discontinuous solution space. The model considers daily water inflows, limits on reservoir level, power generation depends on the available head of hydro units caused by power variations, start-up, and shut-down of hydro units. Moreover, hydro generation prediction typically has composite structures such as non-linearity, non-stationarity, and fluctuation due to unexpected variable of input parameters, which converts its prediction to be very tough. Artificial intelligence (AI) methods are normally selected to deal with this problem. However, they are suffering from partial optimization, falling in solutions of local minima, and low speed of convergence. To deal with these problems, this thesis introduces three approved intelligent controllers for hydropower generation. Firstly, a hybrid algorithm namely firefly particle swarm optimization (FPSO) and series division method (SDM) based on the practical swarm optimization and the firefly algorithm is proposed. In the FPSO method, the local search is performed through the modified light intensity attraction step with PSO operator. Secondly, this approach hybridizing the FA with the rough algorithm (RA), where RA is used to control the steps of randomness for the FA while optimizing the weights of the standard BPNN model. After that, the stationary simulation prediction model is obtained. Thirdly, a novel normalized firefly fuzzy control method (NFANN) is designed for stability control of a hydro-turbine system. Moreover, the more relaxed and simplified sufficient stability conditions are given as a new set of right-angle triangle membership function (RFANN), which has been guaranteed by strict mathematical derivation. The proposed methods tested on raw data of hydropower plant of Himreen Lake Dam. The optimal hydropower generation that observed is increased to the maximum over the actual value by PSO, SD-PSO, SD-FA, and FPSO increased by 1.5%, 2.3%, 3.1%, 2.5% respectively. The proposed SD-FA controller showed better and robustness compared to the other algorithm, which could resist the random disturbances
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