Majlesi Journal of Energy Management
Volume:2 Issue: 4, Dec 2013

One of the most important components of fluid transfer systems are control valves which are seen in different routes of oil and gas pipelines and etc. The most important issue of control valves is flow property to achieve good behavior of valve for controlling the flow rate or pressure. In the present study, a flow control valve with appropriate flow property is designed and modeled in order to reduce the effect of vibration and intensive noise. Using fluid modeling of control valve, the valve flow is simulated by numerical solution in CFX software to develop analytical result for designing the internal profile of the flow control valve such that the flow properties and flow rate considering needs. In this study, an internal profile of a valve sample with certain control properties is designed in Catia software and then analyzed using CFX software. To assess the accuracy of the modeling results, the results obtained here are compared with information on the location of the pipeline.

Wind turbines are systems that harness the kinetic energy of the wind for useful power. Wind flows over the rotor of a wind turbine, causing it to rotate on a shaft. The resulting shaft power can be used for mechanical work, like pumping water, or to turn a generator to produce electrical power. This paper is devoted to an aerodynamic modeling of Isfahan wind-turbine rotor. We first embark on modeling the wind Stream and then, we introduce the coefficient of performance Cp for wind-turbine by modeling an ideal rotor and expressing Betz limit. Afterwards, we model the rotor in a real state and by expressing the extracted formulas, we determine the coefficient of performance; rotor mechanical power; and rotor torque applied to the shaft, etc.

Nowadays use of renewable energy sources has received considerable attention because of reducing bad effect of utilizing conventional power plants in electrical networks. That is why wind power has been noticed by scientists all around the world. In this paper impacts of STATCOM in a distribution network in two modes, connected and island It is examined in presence of wind farm as local loads. In order to achieve this goal we consider two states. One of them is analyzing case study by PSAT software without STATCOM. The other one is analyzing it using STATCOM. At the end, results reveal that voltage profile with STATCOM is much better than another state without STATCOM.

This paper investigates a comparison between the sensorless vector control method based on MRAS (Model Reference Adaptive System) using SVPWM (Space Vector Modulation) and the control method of the PMSM (Permanent Magnet Synchronous Motor) Based on anti-saturation current controller.MRAS algorithm is based on comparison between the estimators. The error between the estimated quantities obtained by the two models is used to estimate the rotor speed that started in order to create an optimum vector control method.This method is compared with vector control based on anti-saturation current control block. That created in order to reduce the ripple in vector control current. These two control method were simulated in MATLAB and after comparing the current THD (Total Harmonic Distortion) of the two methods, it was observed the vector control based on anti-saturation block with shaft encoder has bigger volume, less current ripple and more cost than sensorless method.