To damp the low-frequency oscillations which occurred due to the disturbances in the electrical power system, the generators are equipped with Power System Stabilizer (PSS) that provide supplementary feedback stabilizing signals. The low-frequency oscillations in power system are classified as local mode oscillations, intra-area mode oscillation, and interarea mode oscillations. Double input multiband Power system stabilizers (PSSs) were used to damp out low-frequency oscillations in power system. Among dual-input PSSs, PSS4B offers superior transient performance. Power system simulator for engineering (PSS/E) software was adopted to test and evaluate the dynamic performance of PSS4B model on Iraqi national grid. The results showed that after installing the PSS in a specific plant the oscillation of rotor angle, bus frequency, speed, power flow is better than without PSS during the disturbances that occurred during the simulations. All the PSS/E simulation and tests were done in the National dispatch center (NDC) laboratory, Ministry of Electricity.
Thermal evaporation method has used for depositing CdTe films
on corning glass slides under vacuum of about 10-5mbar. The
thicknesses of the prepared films are400 and 1000 nm. The prepared
films annealed at 573 K. The structural of CdTe powder and prepared
films investigated. The hopping and thermal energies of as deposited
and annealed CdTe films studied as a function of thickness. A
polycrystalline structure observed for CdTe powder and prepared
films. All prepared films are p-type semiconductor. The hopping
energy decreased as thickness increased, while thermal energy
increased.
Tested effective Alttafaria some materials used for different purposes, system a bacterial mutagenesis component of three bacterial isolates belonging to different races and materials tested included drug Briaktin
Been using a pv system program to determine the solar window for Baghdad city . the solar window for any location can be determine by deviating left and right from the geographical south as well as deviation according to the amount of tilt angle with the horizon for fixed panel so that will not change the average of solar radiation incident over the whole year and this lead to help in the process of installation of fixed solar panel without any effect on annual output .the range of solar window for Baghdad city between two angles ( -8 - +8 ) degrees left to right of the geographical south and tilt angle that allowed for the horizon range between angles (21- 30) degrees so that the amount of solar radiation that falling on the solar pan
... Show MoreThis paper presents a fuzzy logic controller for a two-tank level control system, which is a process with a dead time. The fuzzy controller is a proportional-integral (PI-like) fuzzy controller which is suitable for steady state behavior of the system. Transient behavior of the system was improved without the need for a derivative action by suitable change in the rule base of the controller. Simulation results showed the step response of the two-tank level control system when this controller was used to control this plant and the effect of the dead time on the response of the system.
3D models delivered from digital photogrammetric techniques have massively increased and developed to meet the requirements of many applications. The reliability of these models is basically dependent on the data processing cycle and the adopted tool solution in addition to data quality. Agisoft PhotoScan is a professional image-based 3D modelling software, which seeks to create orderly, precise n 3D content from fixed images. It works with arbitrary images those qualified in both controlled and uncontrolled conditions. Following the recommendations of many users all around the globe, Agisoft PhotoScan, has become an important source to generate precise 3D data for different applications. How reliable is this data for accurate 3D mo
... Show MoreIn most manufacturing processes, and in spite of statistical control, several process capability indices refer to non conformance of the true mean (µc ) from the target mean ( µT ), and the variation is also high. In this paper, data have been analyzed and studied for a blow molded plastic product (Zahi Bottle) (ZB). WinQSB software was used to facilitate the statistical process control, and process capability analysis and some of capability indices. The relationship between different process capability indices and the true mean of the process were represented, and then with the standard deviation (σ ), of achievement of process capability value that can reduce the standard deviation value and improve production out of theoretical con
... Show Moreمن الاهمية دراسة التاريخ كونه يمدنا بحلول للمشكلات المعاصرة في ضوء خبرات الماضي، ودراسة سلبيات وايجابيات هذه الحلول، وانطلاقا من مبدأ أن ذوي الإعاقة البصرية طاقة بشرية لابد من استثمارها بما يخدم تقدم وازدهار المجتمع، فمن الأهمية تسليط الضوء على هذه الفئة والإسهام بنقل صورة مشرفة عنها، قد تكون دافعا للآخرين ممن اوقفهم انطفاء شعاع النور والبصيرة عن اكمال حياتهم لشرارة امل تعيد لهم شغفهم في الحياة، وته
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