A Modelling Tool for Distribution Networks to Demonstrate Smart Grid Solutions

The increased deployment of low carbon technologies in power distribution networks, particularly at the distribution level, is expected to cause significant problems to network operation unless existing networks are appropriately adapted and actively controlled as part of a smart grid. This paper describes the development of a modelling tool to examine Smart Grid solutions to a number of issues affecting low voltage power distribution networks. Use of the tool in the context of transformer overload, line overvoltage, active load control, Grid storage and Black Start analysis is examined

Evaluation of domestic electrical demand and its effect on low voltage network performance

Electrical demand in a house depends on various factors mainly being the user’s behaviour and the rating of the appliances. Some researchers have used daily domestic electrical demand profile at half hour time resolution for the energy management. When data of half hour time interval is used for the analysis of on-site generation, it can lead to over/under -estimates of the proportion of generated energy used on site. As a consequence, this could lead to over/under-estimating in the import and export of power from and to the power grid. In this paper, domestic electricity use profile recorded at high time resolution of one minute is used to analyse the profile obtained at different time resolution and its effect on on-site generation. Daily load profile for summer and winter at time resolution of 30 minute is generated from a data set of 22 houses consisting data of a whole year which is then compared with the daily load curve obtained after diversity maximum demand from the literature. The generated daily load profile is then used to see effect on the low voltage network. For the analysis on the low voltage network, a typical UK low voltage network is developed in the Matlab/Simulink softwar

Maximum power point tracking for variable-speed fixed-pitch small wind turbines

Variable-speed, fixed-pitch wind turbines are required to optimize power output performance without the aerodynamic controls. A wind turbine generator system is operated such that the optimum points of wind rotor curve and electrical generator curve coincide. In order to obtain maximum power output of a wind turbine generator system, it is necessary to drive the wind turbine at an optimal rotor speed for a particular wind speed. In fixed-pitch variablespeed wind turbines, wind-rotor performance is fixed and the restoring torque of the generator needs to be adjusted to maintain optimum rotor speed at a particular wind speed for maximum aerodynamic power output. In turbulent wind environment, control of wind turbine systems to continuously operate at the maximum power points becomes difficult due to fluctuation of wind speeds. Therefore, special emphasis is given to operating at maximum aerodynamic power points of wind rotor. In this paper, the performance of a Fuzzy Logic Maximum Power Point Tracking (MPPT) controller is investigated for applications on variable-speed fixed-pitch small- scale wind turbines

Genetic polymorphism of drug oxidation in the rat

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Improving the Performance of a Spouted Bed via Uniformity Index Using Stochastic Optimization

This work focuses on maximizing the solid's uniformity structure (UI) that could enhance the performance of the spouted bed. Furthermore, UI is affected by operating conditions, which are considered as decision variables of the optimization process. The selected decision variables are; gas velocity, solid's density and solid's diameter. Steady-state measurements were carried out in the 60° conical shape spout-air bed. Concentration of particles (glass and steel beads) at various elevations of the bed under different flow patterns were measured using sophisticated optical probes. Optimization technique is a powerful tool for selecting the best operating conditions could overcome the instability of the system and improves the uniformity of the particles across the bed. The stochastic global genetic algorithm has found the suitable search for the non-linear hybrid spouted bed. The optimal results indicate that maximum UI is 0.534 could be obtained with; gas velocity of 0.741 m/s, solid's diameter of 1.09 mm and solid's density of 6648.0 Kg/m3. Velocity of gas and diameter of solid particles were observed the sensitive variables with the uniformity index changing. Keywords: Genetic algorithm, Optimization, Spouted bed, Uniformity index

Simulation and Optimization of a Continuous Biochemical Reactor

The present work focused on the dynamic and optimization of a continuous biochemical reactor using the glucose as a substrate. Simulated model provides the development of the process and reducing the risk of experimental runs. The selected process variables are; dilution rate (D), feed substrate concentration (Si), pH and temperature (T).The  major effect of D was observed at Si below 20 g/L. pH and T are affecting within Si of 60 g/L.Si is the effective process variable on the dynamic characteristics of the reactor. Reasonable agreement has found when compared the simulated results with that obtained by the previous work .Optimization technique guides the decision maker to select the best operating conditions.Stochastic genetic algorithm has found suitable for the nonlinear reactor.Optimal results indicate that the maximum biomass concentration (X) is 80.57 g/L at Si of 197.56 g/L and low D of 0.1(1/hr).Si was the sensitive variable for changing of the objective X.   Keywords: Biochemical reactor; Dynamic model; Optimization; Simulation