Wind is the world’s fastest growing electric energy source. Because it is intermittent, though, wind is not used to supply baseload electric power today. Interconnecting wind farms through the transmission grid is a simple and effective way of reducing deliverable wind power swings caused by wind intermittency. As more farms are interconnected in an array, wind speed correlation among sites dec...

This paper presents 500 KW three phase standalone photovoltaic systems supplying pumping station consist of four pumps 80 KW rating. The system utilizes a two stage energy conversion power conditioning unit topology composed of a DC-DC boost converter and three level-three phase voltage source inverter (VSI). The Boost converter in this paper is designed to operate in continuous mode and contro...

In this paper optimal torque control (OTC) of stand-alone variable-speed small-scale wind turbine equipped with a permanent magnet synchronous generator and a switch- mode rectifier is presented. It is shown that with OTC method in standalone configuration, power coefficient could be reached to its maximum possible value, i.e. 0.48. An appropriate control algorithm based on turbine characterist...

The impact of wind turbines and photovoltaic systems on network operation and power quality (harmonics, and voltage fluctuations) is very important. The capability of the power system to absorb this perturbation is dependent on the fault level at the point of common coupling. The paper deals with power quality case studies conducted on existing renewable resources-based systems. Voltage fluctua...

The integration of renewable sources within the existing power system affects its traditional principles of operation. The renewable energy sources (RES) can be used in small, decentral‐ ized power plants or in large ones, they can be built in small capacities and can be used in different locations [1]. In isolated areas where the cost of the extension of the power systems (from utilities point...

Aim of the study: Firstly, to evaluate K dynamics soils through a quantity-intensity isotherm study; and secondly, characterize on basis (Q/I) parameters.Area Gazipur, BangladeshMaterial methods: Eleven collected from major agro-ecological zones in Bangladesh were evaluated for their varying parameters, supplying capacities these described.Main results: The Q/I plot showed both linear polynomia...

This article reviews literature on competitiveness of agricultural product and input markets. Although researchers in the United States and Europe emphasize different stages of the agricultural and food marketing system, their focus is similar: extent of buyer power, although both have largely ignored the sector supplying inputs to agriculture. The key conclusion is that there is little robust ...

This paper deals with the detailed of a hybrid model of a solar / wind in Simulink, which is using battery as its storage system. The simulation includes all realistic components of the system, in this system power delivered by the combine system component is compared with each other and various conclusions are drawn. A comparative study of hybrid model solar /wind system has been made. This pa...

A rechargeable battery is a convenient form of providing power for an indirect ophthalmoscope when conducting a ward round in a retinal unit, and disposes of the need for connexion to a mains supply at each bedside. Nickel-cadmium cells are widely used in industry and are admirably suited to the supply of power to ophthalmoscopes because of their almost constant voltage during discharge. The li...