JOURNAL OF ELECTRICAL ENGINEERING DEPARTMENT, TRANSACTION ON ELECTRICAL TECHNOLOGY (ELECTRONICS AND POWER)
Year:2009 | Volume:1 | Issue:3|Papers Count:9

A single DC motor can be substituted by two different couple DC motors in submarines. By this way, by varying the speed of submarine, the power of propellant and subsequently the mechanical power of these motors would vary. One important promlem in controlling the mechanical coupling of these motors is the power sharing between them. In the previous reports the mechanical power was shared between them in nonoptimized manner. In this paper an optimized cantroller is indroduced that optimize the efficiency of the system. The power sharing between these motors would vary according to their speed. The proposed controller is based on Genetic Algoritm and is able to share the mechanical power between the motors in an optimized manner at different speeds. The simutation results shows the well behavior of system and also the optimize power sharing.

Power system engineers are forced to place more emphasis on reducing losses at the distribution level. From an economic perspective, Joint network reconfiguration and capacitor placement is one of the best ways to save energy.Application of heuristic technique is unavoidable, because of expansion of distribution networks and becoming more complex connections in these grids. In view of this, for the first this paper investigates the ability of Bacterial Foraging Algorithm (BFA) for Joint network reconfiguration and capacitor placement.

In this paper, a nonlinear model for the body resistance of a 45nm PD SOI MOSFET is developed. This model verified on the base of the small signal three-dimensional simulation results. In this paper by using the three-dimensional simulation of ISE-TCAD software, the indicating factors of body resistance in nanometer transistors and then are shown, using the surface potential model. A mathematical relation to calculat the body resistance incorporating device width and body potential was derived. Excellent agreement was obtained by comparing the model outputs and threedimensional simulation results.

This paper presents analysis of active power filters for enhancing power quality of industrial systems in presence of harmonical pollutions Shunt active power filters proposed for improving power factor, the method of extracting the reference current is presented, and, experimental results of 2 KVAR prototypes are demonstrated.

In this paper, in order to overcome the coupling and fabrication constraints of microstrip structures, 3 layer stripline structure be introduced and based on impedance steps and microwave coupled lines as impedance inverters and multi mode resonators, new and miniaturized structures are proposed. Using this structure, several 2-6 GHz wideband filters has been designed and simulated, and some effective techniques to reducing virtual resonances and improving slope of filter introduced. Finally, a wideband filter is fabricated and using simulation and measurement, efficiency of method is shown.

License plate is the most suitable information for automobile identification. Auto license plate recognition system is an automatic process which extracts the plate number using photographs of the auto. The method presented in this paper consists of two stages. First, the plate is located by edge detection and morphological techniques. Second, the characters are identified using Hopfield neural network. The proposed method has been tested on 700 photos with different backgrounds, distances and angles. The correct plate location and identification are evaluated 97.8% and 93% respectively.

Knowledge extraction from detected document image is a complex problem in the field of information technology.This problem becomes more intricate when we know, a negligible percentage of the detected document images are valuable. In this paper, a segmentation-based classification algorithm is used to analysis the document image. In this algorithm, using a two-stage segmentation approach, regions of the image are detected, and then classified to document and non-document (pure region) regions in the hierarchical classification. In this paper, a novel valuable definition is proposed to classify document image in to valuable or invaluable categories. The proposed algorithm is evaluated on a database consisting of the document and non-document image that provide from Internet. Experimental results show the efficiency of the proposed algorithm in the semantic document image classification. The proposed algorithm provides accuracy rate of 98.8% for valuable and invaluable document image classification problem.

A UPS inverter operates in wide load impedance ranges from resistive to capacitive or inductive load. At the same time, fast transient load response, good load regulation and good switching frequency suppression is required. The variation of the load impedance changes the filter transfer characteristic and thus the output voltage value. In this paper, an analysis and simulation of the single phase voltage source uninterruptible power supply (UPS) with fourth order filter (multiple-filter) in output inverter, based on the state space averaging and small signal linearization technique, is proposed. The simulation results show the high quality sinusoidal output voltage at different loads, with THD less than %5.