High Performance Speed Control of Interior Permanent Magnet Synchronous Motors with Maximum Power Factor Operation

High Performance Speed Control of Interior Permanent Magnet Synchronous Motors with Maximum Power Factor Operation

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Part of #High Performance Speed Control of Interior Permanent Magnet Synchronous Motors with Maximum Power Factor Operation# :

Publishing year : 2003

Conference : Eighteenth International Conference on Electricity

Number of pages : 9

Abstract: In this paper, a high performance control is applied to the speed control of internal permanent magnet synchronous motors. The design strategy is performed with a constraint on the power factor, i.e., the power factor is maximized. In order to improve the performance of the control system, a decoupling current vector control strategy is developed to ensure high performance performance. Simulation results show the effectiveness of the proposed controller.

Study on size effect of RC deficient beam-column joints with and without retrofitting under cyclic loading

Study on size effect of RC deficient beam-column joints with and without retrofitting under cyclic loading

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Part of #Study on size effect of RC deficient beam-column joints with and without retrofitting under cyclic loading# :

Publishing year : 2012

Conference : 6th International Conference on Science and Technology

Number of pages : 10

Abstract: Available theories of material behavior that predict size effects are receiving increasing attention in the technical literature nowadays. Beam-column joint is one of the vital elements, whose behavior during the earthquake is very critical. No study has been done till today to establish the existence of size effect on beam-column joint. Therefore, in the present study, an experimental program was undertaken by considering shear deficient beam-column joints. Three geometrically similar specimens were considered as control specimens and three corresponding specimens were retrofitted by FRP (fiber reinforced polymer). Cyclic loading with a constantaxial load on the beam-column joint was applied during testing. The recorded data were plotted to draw a hysteretic response, an envelope curve, an energy dissipation, etc. Comparisons of results were made between control and retrofitted specimens in the context of all the above-mentioned properties and conclusions were drawn regarding the benefits derived from the retrofitting. Further, the percentage gain in capacity due to retrofitting, energy dissipation, etc. were correlated with size of specimens. To compare the energy dissipation of specimens having different sizes, a new parameter, viz. Energy dissipation per unit volume (eN) was introduced for the first time in the context of the evaluation of size effect. The eN was correlated with the size of the specimen at different drift angles. Stresses for all the specimens were calculated and bilogarithmic plots were drawn. It was observed that most of the properties follow the principle of size effect. The most important finding is that the bi-logarithmic plot of unit strength follows the established law by Bazant.

Parameter Estimation of Induction Motors by PSO Algorithm

Parameter Estimation of Induction Motors by PSO Algorithm

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Part of #Parameter Estimation of Induction Motors by PSO Algorithm# :

Publishing year : 2014

Conference : Second National Conference on Electrical Engineering in Iran

Number of pages : 6

Abstract: After the emergence of alternative current networksand their popularity, asynchronous motors have become more widespread than other types of industrial motors. In order to control and run these motors efficiently, a detailed estimation of motor parameters is required. There are various methods toobtain these parameters such as rotor locked test, no load test, DC test, analytical methods, and so on. The most commonly used method of these methods is their inaccuracy in estimating some motor parameters. In order to remove this concern, a new method for parameter estimation of induction motors using particle swarm optimization (PSO) algorithm is proposed. In theproposed method, the transient state of the motor is used for parameteristimation. Comparison of the simulation results pertained to the PSO algorithm with other available methods justifies theeffectiveness of the proposed method.

A NEW SHAKEMAP METHODOLOGY – APPLICATION TO BUCHAREST, ROMANIA

A NEW SHAKEMAP METHODOLOGY – APPLICATION TO BUCHAREST, ROMANIA

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Part of #A NEW SHAKEMAP METHODOLOGY – APPLICATION TO BUCHAREST, ROMANIA# :

Publishing year : 2007

Conference : 5th International Conference on Seismology and Earthquake Engineering

Number of pages : 5

Abstract: We are developing a methodology for a database for the Romanian capital of Bucharest, which can be quickly calculated and delivered to the public, once sufficient data is available for real-time data access. A systematic incorporation of the previous seismological observations of a weak and strong ground movement and a recent urban broadband experiment in Bucharest allows us to interpolate computed seismic intensities from 11 sites where accelerometers measure the actual motion of a particular earthquake to 31 additional locations in the city, so that a reasonably reliable distribution of ground motion in the city can be determined. We demonstrate this methodology using the MW = 6.0 intermediate-depth earthquake of October 27, 2004.

Impact Response of Simply-Supported Beams

Impact Response of Simply-Supported Beams

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Part of #Impact Response of Simply-Supported Beams# :

Publishing year : 2014

Conference : First National Conference on Civil Engineering and Sustainable Development of Iran

Number of pages : 7

Abstract: The most fundamental problem that should be considered in the thesis of vehicle-induced vibrations on bridges is the dynamic response of a simply-supported beam subjected to a single movingload. This problem is important in that the solution can be given in an inclosed form. In this chapter, the impact formulas will be derived for thedeflection, bending moment and shear force of a simple beam under a single moving load. By the principle of superposition, the solutionobtained for a single moving load will be expanded to deal with a series of identical, equidistant moving loads, by which the key parameters that dominate the beam beam can be identified. Additionally, based on the conditions of the resonance or Cancellationfor the waves generated by a series of moving loads, optimal designcriteria for suppressing the resonant response of beam structures willbe presented. In the design of a high-speed railway bridge, such criteriaare useful for the selection of the span length and cross section of the agirder bridge, if the car's length, axle distance and operating speed of the train are already decided.

Single Z-source Based Cascaded Transformer Multilevel Inverter

Single Z-source Based Cascaded Transformer Multilevel Inverter

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Part of #Single Z-source Based Cascaded Transformer Multilevel Inverter# :

Publishing year : 2011

Conference : Third International Electronic Power and Drive Systems Conference

Number of pages : 6

Abstract: This paper proposes a new topology of a cascaded transformer based multi-level inverter using a single Z-source. The proposed circuit consists of only one Z network and a single DC voltage source, as a result of which the installation area is reduced. In this topology, the output voltage amplitude is not limited to DCvoltage source and transformers, the ratios are similar to traditional cascaded transformer based multi-level inverters and can be increased with Z network shoot-through state control. Moreover, it is more reliable against short circuit. In this paper, using a particular switching algorithm, the modulation index of the inverter is kept constant and the output voltage is controlled by a shoot-through duty ratio, so the total harmonic distortion (THD) of the output voltage is almost constant for different boostratio. The performance of the proposed inverter and the switching algorithm are validated with simulation results using MATLAB / SIMULINK software.

Fault Detection Using Ant-tracking Attribute in One of Southern Offshore Iranian Fields and Comparison with Other Related Attributes.

Fault Detection Using Ant-tracking Attribute in One of Southern Offshore Iranian Fields and Comparison with Other Related Attributes.

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Part of #Fault Detection Using Ant-tracking Attribute in One of Southern Offshore Iranian Fields and Comparison with Other Related Attributes.# :

Publishing year : 2010

Conference : Fourteenth International Conference on Oil, Gas and Petrochemicals

Number of pages : 6

Abstract: fault detection is one of the most important steps in seismic interpretation either in exploration or in development phase. There are a variety of seismic attributes enhancing fault visualization and detection already used by interpreters. The on-tracking attribute is improved by schlumberger and is commercially available in petrel soft ware.it emulates the behavior of colonies in nature and how they use pheromones to mark their paths in order to optimize the search for food. What we've done is working on an -tracking attribute which is a very powerful attribute in fault detection that can give us fault patches both automatically and manually. In this study, the general workflow to provide an acceptable and clear result showing a precise trend and path of faults, which requires a significant amount of manipulation of related parameters, each of which has been discussed separately. An automatic tracking attribute cube that has not only shown a very good match, but also some minor defects which can not be easily detected by routine interpretation, are visible on the ant-tracing attribute Cube

Numerical Solution of Grouting of impermeable wall

Numerical Solution of Grouting of impermeable wall

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Part of #Numerical Solution of Grouting of impermeable wall# :

Publishing year : 2008

Conference : The second national conference of the country's hydroelectric plants

Number of pages : 10

Abstract: The basic phenomenon of grout propagation has been attempted to be described as continuous in deformable saturated porous media. The fluid-displacement results in a highly coupled and non-linear system require specific numerical techniques. This paper describes a new approach to modeling the injecting domain based on Darcyan flow and theory of consolidation. The proposed model utilizes the variation of the coefficient of permeability with respect to pore fluid pressure based on a Darcian flow characteristic below certain hydraulic gradients. The potential of the proposed model is evaluated in predicting the propagation of grouting due to a single injection bore hole. The general comparison shows that this approach is capable of solving the injection boundary value problem. A simple rule is based on the percentage of overlapping two domains affected by two side by side injection bores, which is to carry out the effective thickness of the insolated cut-off wall. Accordingly, the priority of the first injection bore hole and the provided impedability of the corresponding domain and the interaction of the second domain with the previous one have been considered. This simple rule can lead to the solution to carry out an average effective thickness of the insolated wall over the proposed model.

Challenges for commercialization of biotechnology products:cases of R&D spillover from Iranian experts abroad

Challenges for commercialization of biotechnology products:cases of R&D spillover from Iranian experts abroad

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Part of #Challenges for commercialization of biotechnology products:cases of R&D spillover from Iranian experts abroad# :

Publishing year : 2014

Conference : Second International Technology Conference

Number of pages : 13

Abstract: Developing and commercializing new products has always been a complex task for research and development practitioners, business people and investors. There are often common challenges such as market forces, being new, lack of trust, high cost of R & D and resistance from previous products, which prohibits the success of new products commercialization. However, when dealing with new high-tech. Products such as biotechnology products the case is often different. Employing a Framework for Political, Economic, Social, Technology and Legal (PESTL), the article explores the specific challenges faced by the Iranian elites and exerts themselves abroad, when trying to transfer their knowledge, expertise and technology back to home for business purposes.

novel method for trajectory control of spherical parallel manipulator based on neural network

novel method for trajectory control of spherical parallel manipulator based on neural network

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Part of #novel method for trajectory control of spherical parallel manipulator based on neural network# :

Publishing year : 2010

Conference : The first regional engineering conference

Number of pages : 4

Abstract: Robot control for singular points is based on learning and predicting their coordinates in the next time, is one of the most important method in robot kinematics and dynamics. This paper presents a simple and novel method for parallel manipulator singularityfree path. A modified 4-5-6-7 interpolating polynomial is used to plan a trajectory for a spherical parallel robot. The polynomial function, which is smooth and continuous in displacement, velocity, acceleration and jerk, is used to find a smooth path avoiding the singularities. This proposed algorithm can specify the optimized path criteria with the maximum number of condition points for all path points. An artificial neural network is implemented to solve the kinematics of the manipulator to estimate the distance between a gripper and a singularity. The simulating results prove the efficiency of the proposed algorithm.