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Faculty of Engineering and Built Environment

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    Load frequency control of a hydro dominating interconnected power system
    (2020-12) Joshi, Milan; Sharma, Gulshan; Davidson, Innocent Ewaen
    Energy is one of the vital figures that impact the development of civilization in the 21st century. It has been projected that by the year 2050, global energy needs will be satisfied by renewable sources. Among these renewable energy resources hydropower is available worldwide with relatively cheaper accessibility for most of the communities. Nevertheless, hydropower's control architecture raises concern for the system operators in terms of preserving the Load Frequency Control (LFC) services due to the elongated response time of hydro turbines in catering for the varying load demands. The varying load demands are inevitable in the power system due to different clients’ energy consumption patterns at different times. This, therefore, places changing control framework requests as per the requirement of diverse clients. Hence, the research proposes and demonstrates the connection of the hydro-hydro framework through the AC tie- line for LFC. The Linear Quadratic Regulator (LQR) is a plan for hydro overseeing framework in discrete mode. The application derived is displayed through closed- loop feedback gains and closed-loop eigenvalues. In the expansion model, the positive effect of a Unified Power Flow Controller (UPFC) and Redox Flow Battery (RFB) in LFC studies is investigated. This proposition moreover shows the joint endeavors of Fuzzy Logic (FL) as well as Proportional Integral Derivative (PID), with control gains well-calculated, through Particle Swarm Optimization (PSO) result into a robust FL-PSO-PID for LFC of the connected hydro framework. The different errors are defined to assess the yield as well as the execution of the FL-PSO-PID. The yield appears through a decline in blunder values as well as minimization in framework responses from accurate estimation for the LFC under various working conditions such as non- linearity, random load alteration, and parametric move as a result of a precise estimate. In the expansion, the effect of energy storage devices is also investigated to understand the enhancement provided frequency control of the hydro system, and the result obtained shows their effectiveness. Finally, the outcomes and future extent of this investigation work have been presented.
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    Hydrological characterization of twelve water catchments in Nigeria
    (AJER, 2014-01) Afolayan, S.O.; Adeyemo, Josiah; Otieno, Fredrick Alfred O.; Ojo, Olumuyiwa I.
    Twelve water catchments (WCs) in Ogbomosho, south west of Nigeria were evaluated for their hydrological characterization with respect to domestic and irrigation activities. Both physiochemical and biological parameters (limnological properties) were determined which include pH, total alkalinity (TA), CO32-, HCO3-, NO3-N, SO42-, N, P, K, Na, Ca, Mg, dissolved oxygen (DO), electrical conductivity (ECw), biochemical oxygen demand (BOD), total solids (TS), total dissolved solids (TDS), chlorophyll a,b,c and phaeophytin. Temperature fluctuation of the water catchments was measured in-situ to avoid samples coming into contact with the surrounding air using mercury in glass thermometer. Soil samples collected from the bottom of the water catchments were determined for chemical properties such as N, P, K, Na, Ca, Mg, and SO4-2 following recommended procedures. These parameters were investigated based on the perceived research consent of their efficacy in characterizing water catchments hydrologically along safety and pollution divides. The limnological properties were configured into ranking compared with standards to evaluate the degree of contamination or suitability of the WCs for domestic and irrigation purposes. Results obtained indicated pH values of the catchments ranging from 5.8 to 7.4 with corresponding TA between 0 and 296 mgL-1 suggesting high level of dissolved carbon dioxide (DCO2) and traces of untreated wastewater in most of the catchments. Based on ranking of the limnological properties of the WCs, WC4, WC5, WC6 recorded indices between 65 and 95 signifying that cumulatively these three WCs were more prone to pollution and could affect human health at consumption while WC2, WC3, WC 7 and , WC 10, aligned between 95 and 120 indicating mild to medium pollution and WC1, WC 11, and WC 12 oscillated between 120 to 145 picturing WCs approaching standards (132) while WC8 ranged between 145 and 170 revealing WC 8 as catchment with little or no tendency for hazards at drinking. Similarly, WC2, WC8, recorded soil reference (SR) between 50 and 60 suggesting possible interference of organic decomposition between the soil stratum and water in the catchment, however, WC1, WC4, WC5, WC6, WC7 and WC 12 recorded SR between 40 and 50 showing possible adjustment of the soils in the WCs of various salinity levels and WC 3, WC9, WC 11 revolving between 30 and 40 projecting the WCs with minimal pollution. Moreover, WC 10 only recorded value between 20 and 30, an inference of the soil stratum void of absolute contamination. Generally, WC2, WC8, appeared polluted both in limnological properties and basic soil conditions while WC9, WC10, WC11, and WC3 reflected high scale of ranking on limnological properties with low scale of SR possibly indicating little or no interaction between the soil base and the water in the catchments. Contrary wise, WC6 was high in SR but low in limnological properties. This trend suggests the presence of oxygen saturation in some of the WCs. Overall results indicated that WC4, WC5, WC6 require major water treatment prior to its usage for irrigation to avoid salt deposition at the crop root base, while WC2, WC3, WC7, WC9 and WC10 were considered relatively safe for drinking. WC1, WC11, WC2 requires some measure of precaution before drinking, however, WC12, and WC 8 could be consumed with little or no fear of infection.