Browsing by Author "Muhammad Salik"

Now showing 1 - 4 of 4
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    Dynamic modeling and characterization of a proton exchange membrane fuel cell
    (2012) Muhammad Salik; Abdul Aziz Bhatti; Mashood Nasir
    This paper presents the equivalent dynamic model accounting for the thermodynamic and electrochemical characteristics of Proton Exchange Membrane Fuel Cell (PEMFC). The proposed model was implemented in MATLAB/SIMULINK environment. The effects of temperature variations, fluid flow changes and capacitance due to double layer charging were incorporated in this model. The proposed model responses are in good correspondence with the published experimental results. It also predicts the temperature and pressure response of the PEMFC. The model formulated here would be helpful for the optimal prediction of characteristics and dynamic operation of a fuel cell stack.
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    Dynamic modeling and grid integration of a solid oxide fuel cell
    (University of Engineering and Technology, 2013) Muhammad Salik; Syed Mohsin Ali; Abdul Aziz Bhatti; Mashood Nasir
    This article presents an equivalent dynamic model of a Solid Oxide Fuel Cell (SOFC) integrated with utility grid. The proposed dynamic model accounts for the electrochemical and thermodynamic characteristics of SOFC. Effects of temperature variations and fluid flow changes are incorporated in the model. Voltage drops inside a fuel cell are also modeled. This proposed model is further integrated with the utility grid with help of power conditioning unit (PCU). PCU consists of a DC-DC Boost converter and a 3-phase voltage source inverter. The output of 3-phase inverter is fed to the grid with the use of AC link integration. Complete model is formulated in MATLAB-SIMULINK environment. Simulation results clearly depict the behavior of SOFC and also show that SOFC is a potential source for distributed generation purpose. The proposed model formulated here would be helpful for the optimal prediction of characteristics and dynamic operation of SOFC based power plants.
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    Equivalent model development and grid integration of a solid oxide fuel cell
    (UMT.Lahore, 2013) Muhammad Salik
    The research work reported in this thesis is based on mathematical modeling of solid oxide fuel cell (SOFC) and its integration with grid. With the recent advancements in electrochemistry and the increasing demands for environment friendly energy resources, fuel cell technology has gained the major significance due to its compact size, low chemical emissions and low maintenance. Among different types of fuel cells, high temperature SOFC’s are capable for the stand alone high power production and grid-tied applications. Also the increase in demand for electric power, the distributed generation (DG) has attained much attention. DG utilizes alternate energy resources such as photovoltaic systems, wind energy systems and fuel cells. SOFC has proved to be a promising technology for distributed power generation with compact size, high power efficiency and absence of moving parts. SOFC is used as a reliable energy source in case of steady operations, but it shows slow response in case of transient conditions. Researchers have been working from past few years on modeling of SOFC to visualize its behavior under certain conditions. Most of the research articles do not include the detail of losses in SOFC which must be included in the equivalent model for analyzing the actual behavior of the SOFC over the time. In this research work, a mathematical model for a SOFC accounting for thermodynamic limits, effect of temperature and pressure variations is formulated to evaluate and visualize its actual characteristics. Activation, ohmic and mass transport over potentials are also included in the model. For connection of SOFC with grid, an intermediate module (Power Conditioning Unit) is proposed. Power Conditioning Unit (PCU) improves the slow response of SOFC and also steps up the DC voltages. It consists of a boost converter and a 3-phase inverter. PCU sets technical challenges in order to integrate SOFC with the utility grid. The overall modeling and integration of SOFC with the utility grid covers, the detailed representations of equivalent model of SOFC, power electronic modules, transformers and the grid integration technique. The proposed model is implemented in MATLAB-SIMULINK. It can be utilized for visualization of optimum characteristics and operation of grid integrated SOFC stack and its behavior under various operating conditions.
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    Improved fuzzy logics based differential protection scheme
    (International Power Engineering and Optimization Conference, 2013) Muhammad Haris; Muhammad Salik; Ali Arslan Safdar; Umer Rashid
    In this research work, fuzzy logics based differential protection scheme is proposed for power transformer. Membership functions are developed from voltage, frequency and currents at primary side and secondary side of the power transformer. The proposed protection scheme senses the operating conditions and gives trip or no trip signal to the circuit breaker from the fuzzy inference of the small, medium and high values of the membership functions. Simulation results of various operating conditions, shows that the proposed differential relay is reliable, fast and is able to discriminate between internal faults, external faults and magnetizing inrush current. Results also demonstrate selective phase switching and auto-reclosing function of the protection scheme. Fuzzy logics based protection scheme is modeled in MATALAB-SIMULINK environment.