by Sajad Tashakori, Amir Tavakoli and Farzad Mirzaei
Original Research
In this paper the authors tried to design a under excitation limiter and a power system stabilizer which can operate without any kind of interaction. The under excitation limiter (UEL) is intended to prevent reduction of generator excitation to a level where the steady state stability limit or the stator core end-region heating limit is exceeded. The power system stabilizer (PSS) uses auxiliary stabilizing signals to control the excitation system so as to improve power system dynamic performance.
American Journal of Electrical and Electronic Engineering. 2017, 5(1), 28-33. DOI: 10.12691/ajeee-5-1-5
Pub. Date: February 20, 2017
19025 Views2445 Downloads1 Likes
by Danial Haider, Syed Aziz Shah, Syed Ikram Shah and Umer Iftikhar
Original Research
In the present world, the spectrum efficiency along with the capacity and coverage of wireless networks are being improved by wireless specialists. Wireless link performance could be enhanced and improved by using multiple antenna technology called Space time wireless technology. There exists some advancement in the present MIMO techniques which could further improve the overall wireless Local Area Network (LANs) and Wide Area Network (WANs). In Multipath fading performance gain is very important which could be achieved by using an efficient Space-Time Coding (STC) technique. This Space Time coding along with Alamouti Scheme is a very vibrant research topic. In the forthcoming generation of mobile communication there will be a need of high data rate, reliable communication link and vast multimedia capabilities, STBC is the one solution for these. This paper presents the Space-Time Block Codes (STBC) for wireless networks using Alamouti Scheme in which multiple antennas are being used at both transmitter and receiver. The simulations have been done in MATLAB.
American Journal of Electrical and Electronic Engineering. 2017, 5(1), 23-27. DOI: 10.12691/ajeee-5-1-4
Pub. Date: February 18, 2017
19938 Views3943 Downloads
by Milad Ghaisi Rad, Milad Rahmani, Pedram Gharghabi, Ali Zoghi and Seyed Hossein Hosseinian
Original Research
In this paper a new approach has been introduced to find the optimum capacity of a wind farm to cooperate with a hydro-pumped-storage in order to maximize the income and optimize the payback period of their combination. First, Monte Carlo method has been used to generate the annual price and wind speed values. Then, an operating policy has been considered to schedule each unit generating and saving the produced energy by the wind farm. Subsequently, simulations have been carried out in MATLAB M-File environment to show the effectiveness of the presented method. Finally, results are presented in various circumstances to help the owner to select the optimum condition for constructing a wind hydro-pumped-storage system.
American Journal of Electrical and Electronic Engineering. 2017, 5(1), 16-22. DOI: 10.12691/ajeee-5-1-3
Pub. Date: February 07, 2017
27800 Views4205 Downloads3 Likes4 Citations
by Sajad Tashakori, Amir Tavakoli and Farzad Mirzaei
Original Research
In this paper the authors tried to design a under excitation limiter and a power system stabilizer which can operate without any kind of interaction. The under excitation limiter (UEL) is intended to prevent reduction of generator excitation to a level where the steady state stability limit or the stator core end-region heating limit is exceeded. The power system stabilizer (PSS) uses auxiliary stabilizing signals to control the excitation system so as to improve power system dynamic performance.
American Journal of Electrical and Electronic Engineering. 2017, 5(1), 10-15. DOI: 10.12691/ajeee-5-1-2
Pub. Date: January 14, 2017
3536 Views1245 Downloads4 Likes
by M. Ehikhamenle and B.O. Omijeh
Original Research
A microcontroller based tachometer is a device that measures the rotation speed of a shaft or disk in motor or other machines [1]. This device is an embedded system; it is built using a microcontroller, an alpha-numeric LCD module and an infrared system to detect the rotation of the fan whose speed is being measured. The infrared system generates the pulses from the fan which will be sent to the microcontroller and the pulses will be counted; the reading is displayed on the liquid crystal display (LCD module) in revolution per minute (RPM). It is A low cost digital tachometer that can display exact speed reading based on how fast an object is rotating.it adopts the Use infrared transmitter and receiver as the technology behind the speed detection. It can be used in various applications. It can measure the speed of rotating objects (examples of rotating objects include: a bike tyre, a car tyre, a ceiling fan, or any other motor) in the most accurate form possible. In automotives, it is used as a gauge showing the speed (RPM) of the engine shaft that is driving the transmission, usually in thousands of rotations per minute.
American Journal of Electrical and Electronic Engineering. 2017, 5(1), 1-9. DOI: 10.12691/ajeee-5-1-1
Pub. Date: January 06, 2017
29014 Views7557 Downloads1 Likes