Technical and Engineering Campus of Shahid Beheshti University is a state university of technology, engineering and science in Iran. PWUT is also the technical training center for Power and Water industries in Iran. More than 120 academic staff along with more than 100 labs and workshops have made PWUT a unique center that provides an environment to promote a high level of professional performance for trainees from various backgrounds from different Regional Electric Companies, Power Plants and Water and Waste-water Companies. The university is located in north-east of Tehran, Iran. The university is named after Hassan Abbaspour, former Iranian Minister of Energy who was killed in 1981.With more than 30 years of experience and modern technical and training facilities, PWUT offers degree programs. The programs are offered at Bachelors, Masters and PhD levels. In addition, PWUT conducts a wide range of short, specialized courses annually, aimed at upgrading or refreshing the knowledge and skills of practitioners. Most of the faculty members are power and water industry elites. Exceptional laboratories and experimental facilities are the other advantages of the university over the other public universities in Iran. PWUT is one of the well established state universities in Tehran accredited by the Ministry of Science, Research and Technology of Iran. The PWUT is administered by a board of trustees comprising high-ranking independent academicians and representatives of national organizations professors. Wikipedia.
Javadi H.,Power and Water University of Technology, Tehran
International Journal of Electrical Power and Energy Systems | Year: 2011
The necessity and procedure for application of series fault current limiter (FCL) composed to bus sectionalizing in power network of IRAN have been discussed. In this regard, all of the high voltage substations in the power network of IRAN were evaluated in point of view of the fault current amplitude. The short circuit analysis of the power network was done based on the actual and future network specifications which have been designed and published by Iran Generation Transmission & Distribution Company in 2005. The overall results of this analysis and the detail data of using FCL together bus sectionalizing for two of the most important high voltage substations of Iran are presented. This method allows decreasing of 27% in fault current amplitude. The economical observation shows this method can be profitable if high voltage substation contains more than four feeders. © 2010 Elsevier Ltd. All rights reserved.
Ameri M.,Power and Water University of Technology, Tehran |
Mohammadi R.,Power and Water University of Technology, Tehran
International Journal of Energy Research | Year: 2013
Fuel cell is an energy conversion device that transforms the chemical energy of a fuel gas directly into electrical energy without direct combustion as an intermediate step. One type of fuel cell is the solid oxide fuel cell (SOFC) with the operation temperature of around 1273°K. The high operating temperature of the SOFC also provides excellent possibilities for feeding into a gas turbine (GT) to generate additional electricity. In this paper, an atmospheric SOFC and GT hybrid system have been simulated by application of Aspen Plus existing functions and unit operation modules. The study has shown that the system efficiency and voltage reduce continuously as the current density increases due to increase of Ohmic and concentration losses. However, the output power increases due to enhancement of the current density. Therefore, the system should operate at low current density if the goal is to generate power at higher efficiency. Moreover, if the goal is to produce more power, the system should operate at high current density. The simulation results indicate that the cycle can achieve high electrical generation efficiency (68.2%), which is very attractive compared to the ideal efficiency of combined cycle power plants around 50%. Moreover, a parametric analysis has been performed to assess the effects of the several operating condition variation on the system performance. © 2011 John Wiley & Sons, Ltd.
Hashemi S.,Power and Water University of Technology, Tehran |
Aghamohammadi M.R.,Power and Water University of Technology, Tehran
International Journal of Electrical Power and Energy Systems | Year: 2013
Online voltage stability assessment is one of the vital requirements for intricate electric power systems. Due to the restructuring and liberalization, modern power systems tend to operate close to their stability limits with small security margin. In such environment, online voltage stability evaluation plays a significant role in secure operation of power systems. This paper presents a new approach for estimating voltage stability margin VSM, based on application of wavelet feature extraction method to network voltage profile. Voltage profile is adopted as the original input data for VSM estimation, because it contains sufficient information concerning network topology, load level, load-generation patterns and all system controllers. In this approach, in order to provide high discrimination between network voltage profiles, Multi-Resolution Wavelet Transform (MRWT) is utilized to extract the features of voltage profiles. Also, in order to eliminate the redundant features, principle component analysis (PCA) is used to select the most relevant features extracted by MRWT. Radial Basis Function (RBF) neural network is adopted to estimate system VSM using the dominant extracted features of the voltage profile by MRWT and PCA. Using voltage profile as the original data makes the proposed approach capable of estimating system VSM in both static and quasi dynamic conditions. The proposed approach has been implemented in New England 39-bus test system with promising results demonstrating its effectiveness and applicability. © 2013 Elsevier Ltd. All rights reserved.
Avami A.,Power and Water University of Technology, Tehran
Renewable and Sustainable Energy Reviews | Year: 2012
Biodiesel is here considered as an alternative fuel in Iran in order to benefit from environmental aspects and contribution to final energy demand. An analytical tool is developed to consider different scenarios in biodiesel production. This study provides a regional framework in terms of techno-economic parameters to deeply understand the agricultural, technical, and economic aspects of biodiesel supply chain of Iran including resources, production, distribution, and consumer. The study further assesses the potential of biodiesel production in different geographical regions of Iran. It reveals the contribution of current potential resources to make the future biodiesel demand. © 2012 Elsevier Ltd. All right reserved.
Aghamohammadi M.R.,Power and Water University of Technology, Tehran |
Shahmohammadi A.,Power and Water University of Technology, Tehran
International Journal of Electrical Power and Energy Systems | Year: 2012
Cascading failures and blackouts are the most significant threats for power system security. If the process of cascading failure proceeds by further line tripping, the system will face uncontrolled islanding. Establishment of uncontrolled islands with deficiency in MW or Mvar power balance are the main reasons for system blackout. In order to reduce the risk of blackout due to islanding, intentional or controlled islanding has been considered as a preventive strategy. In this paper, for identifying proper islanding scenarios in network, a new search algorithm based on the ant search mechanism is proposed. The security constraints considered for finding islanding scenarios are load-generation balance and line overloading which are implemented using linear programming and DC load flow. The proposed algorithm has been applied on IEEE 39-bus network with promising results showing the ability of the algorithm for finding proper islanding scenarios quickly. © 2011 Elsevier Ltd. All rights reserved.
Khederzadeh M.,Power and Water University of Technology, Tehran |
Ghorbani A.,Power and Water University of Technology, Tehran
IEEE Transactions on Power Delivery | Year: 2012
By utilizing multiline voltage-source (VSC)-based flexible ac transmission system (FACTS) controllers, independent controllability over each compensated line of a multiline system can be achieved. While VSC-based multiline FACTS controllers emerged as a new opportunity to control two independent ac systems, the main constraints and limitations that are presented to the conventional transmission-line protection systems need to be investigated. In this paper, the impacts of VSC-based FACTS controllers on distance relays while controlling the power flow of compensated lines are evaluated analytically and by detailed simulations for different fault types and locations. © 2006 IEEE.
Ashoori Movassagh A.,Power and Water University of Technology, Tehran |
Mahmoodi M.J.,Power and Water University of Technology, Tehran
European Journal of Mechanics, A/Solids | Year: 2013
A Kirchhoff micro-plate model is presented based on the modified strain gradient elasticity theory to capture size effects, in contrast with the classical plate theory. The analysis is general and can be reduced to the modified couple stress plate model or classical plate model once two or all material length scale parameters in the theory are set zero respectively. Governing equation and boundary conditions of an isotropic rectangular micro-plate are derived using minimum potential energy principle. Various boundary conditions including simply supported and clamped edges are covered by the analysis. The extended Kantorovich method (EKM) which is an accurate approximate closed-form solution is applied to solve the resulting sixth order boundary value problem. Application of EKM to the partial differential equation (PDE) yields two ordinary differential equations (ODEs) in the independent x and y coordinates. The resulted ODEs are solved in an iterative manner. Exact closed-form solutions are presented for both ODEs in all of the iteration. It is shown that the method provides accurate predictions with very fast convergence. Numerical results reveal that the differences between the deflection predicted by the modified strain gradient model, the couple stress model and the classical model are large when the plate thickness is small and comparable to the material length scale parameters. However, the differences decrease with increasing the plate thickness. Validation of the presented EKM solution shows good agreement with available literature. © 2013 Elsevier Masson SAS. All rights reserved.
Shahmohammadi A.,Power and Water University of Technology, Tehran |
Ameli M.T.,Power and Water University of Technology, Tehran
Electric Power Systems Research | Year: 2014
Blackouts occur in power networks after cascading failures which separate the network into some uncontrolled islands. These unintentional islands are mostly faced with a deficiency in active or reactive power balance leading to continuing failures and blackouts. Intentional or controlled islanding is one of the best solutions for preventing blackouts during cascading failures. Controlled islanding strategies can be based on different network features such as its topology and distribution of resources in a way that the imposed amount of load shedding will be minimized. Nowadays, the application of distributed generation (DG) units is increasing rapidly and such units can play a significant role in the process of intentional islanding. In this study, a method for proper sizing and placement of DG units in order to aid the intentional islanding process by strengthening the static stability of newly created islands and minimizing the amount of imposed load shedding was analyzed. The proposed method was applied on an IEEE 39-bus network. Simulation results demonstrated the ability and efficiency of proper sizing and placement of DG units from an intentional islanding point of view. © 2013 Elsevier B.V. All rights reserved.
Aghamohammadi M.R.,Power and Water University of Technology, Tehran |
Abdolahinia H.,Power and Water University of Technology, Tehran
International Journal of Electrical Power and Energy Systems | Year: 2014
This paper presents a method for determining optimal size of a battery energy storage system (BESS) for primary frequency control of a Microgrid. A Microgrid is assumed to be portion of a low voltage distribution feeder including sources such as microturbine, diesel generator, fuel cell and photovoltaic system with slow response for frequency control. A BESS due to its very fast dynamic response can play an important role in restoring balance between supply and demand. In this paper, overloading capacity of the BESS is employed for fast handling of the primary frequency control of a MG. To achieve this purpose, by considering overloading characteristics and limitations of the state of charge (SOC) of battery, a control scheme of dc/ac converter for the BESS is developed. Based on this scheme, overloading capacity of the BESS and its permissible duration for participating in primary frequency control is determined. Simulation studies are carried out using PSCAD/EMTDC software package to evaluate the performance of the proposed control scheme. © 2013 Elsevier Ltd. All rights reserved.
Khederzadeh M.,Power and Water University of Technology, Tehran
Electric Power Systems Research | Year: 2010
Thyristor Controlled Series Capacitor (TCSC) as a dynamic system, besides its capability in increasing power transfer in transmission lines, can be used to enhance different power system issues. In this paper, the effect of TCSC on voltage sag following transformer inrush current is investigated. It is shown that excessive transient inrush current occurring during transformer energizing can be mitigated by TCSC. Hence, voltage sag as one of the key components of the power quality is alleviated for the sensitive loads that are connected to the same bus which the power transformer is energized from. During a fault, TCSC can improve the voltage sag by limiting the current and help to keep the voltage as high as possible. Moreover, the inrush currents and the associated voltage sags that usually occur after clearing heavy single-or multistage faults are mitigated by the presence of TCSC. The model used for simulating inrush current is based on the characteristics of the major hysteresis loop out of which the internal trajectories are defined using the translation principal and a linear compensation to generate closed loops. An arctangent relation between the flux and the exciting current is defined. The expression parameters are deduced by curve fitting empirical data defining the major loop or the single-valued saturation characteristic. © 2010 Elsevier B.V. All rights reserved.