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2003 - 200942010 - 201933
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Subject: Electrical Engineering × End date: 2019 ×
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    ThesisItemOpen Access
    Design and performance investigation of line start permanent magnet synchronous motor
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Arvind Kumar; Srivastava, Ajay
    Electric motors are the workhorse of the modern industries and consume about 70 % of the industrial electrical demand. Constructing motors with better efficiency can result in a reduction in energy consumption and cost savings to the consumer. The solution of increasing a motor’s efficiency is to use permanent magnets motors which eliminate the excitation losses experienced by induction machines, thereby increasing the motor’s efficiency. The past 25 years have been a significant period with advances in the development of line start permanent magnet motors. Over this period, these motors have expanded their presence in the industrial and domestic marketplace. LSPMSMs can offer higher efficiency than standard induction motors used in the industry. Due to nonlinear characteristics of magnetic materials, finite element method is considered to be a better approach for design and analysis of line start permanent magnet motors. In order to find the optimized structure, different rotor structures of line start permanent magnet motors are comparatively studied in terms of dynamics and steady state performance. The placement and volume of magnet plays a critical role in motor performance. Three types of rotors with different layers of permanent magnets are proposed and analyzed using finite element method. The performances of three motors are compared to get the best configuration of line start permanent magnet motor.
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    ThesisItemOpen Access
    Investigation of the performance of three phase induction motor under non sinusoidal supply voltages
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-09) Kaushik, Deepak; Srivastava, Ajay
    According the electric power research in 1995, 35- 40% of all electric power flow through electronics converters. That used of electronics devices increased year by year. All the electronic converters are the non- linear load and they generate the harmonics. Harmonics affects the power supply, it affects the voltage, current, and frequency of the power supply and power supply become distorted. The distorted power supply affects the performance of all connected devices. Induction motor is mostly used machine in industrial area as well as commercial area. Induction motor performance also affected by the distorted supply, therefore the study about the performance parameter of induction motor like torque, speed, power factor, torque ripple, losses, efficiency etc. under the distorted supply on MATLAM/SIMULINK. SIMULATION give the quick analysis of the performance parameter, under the positive, negative, and mix harmonics to check the performance of motor under different loading condition. At harmonic contain supply under full load condition efficiency and power factor was increasing with decreasing in harmonic voltages. That observation is same for positive, negative and mix harmonics. But the change is very minor in efficiency and power factor. Speed does not vary with harmonics supply. Ripple is constant for all load at different harmonics. Losses increase due to the harmonics contain supply.
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    ThesisItemOpen Access
    Investigation of power quality impact on the performance of three phase induction motor
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Singh, Sunil; Srivastava, Ajay
    Voltages are well balanced and sinusoidal at the generation and the transmission levels but it gets unbalanced and non-sinusoidal at the utilization or distribution levels due to unequal system impedances, unequal distribution of single-phase loads, and non-linear loading. Voltage unbalance, under/over voltage, and distorted waveform conditions generally occur simultaneously. An excessive level of voltage unbalance, undervoltage, overvoltage, and harmonics can result excess power loss, torque reduction, and torque pulsation in the induction motors. A comprehensive investigation of impacts of voltage unbalance, undervoltage, overvoltage, and harmonics has been done on the performance (loss, efficiency, currents, current unbalance, power factor, torque, speed, speed pulsation, and torque pulsation) of three phase induction motor using MATLAB/Simulink software. Investigation is done by taking the power quality disturbances separately and simultaneously. Some of the results obtained by simulation is also verified by conducting lab experiment on the similar machine and found good agreement with results. A relation is establish to estimate torque ripple factor (TRF) in terms of voltage unbalance factor and total harmonic distortion (THD). It has been concluded that terminal voltage unbalance (TVU) will not affect slightly, but undervoltage unbalance (UVU) affect the motor performance severely and immediate need to derate. It has been recommended that to derate the motor precisely, under/over voltage or positive sequence voltage should also be taken into consideration. The simulation models can be used for further study and research.
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    ThesisItemOpen Access
    An ANN based approach for assessment and improvement in voltage stability of power systems
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2007-02) Negi, Geeta; Swami, A.K.
    Use of new technologies and the growth in interconnections are continuously increasing the complexity of the system. These highly complex modern power systems are operating in severely stressed conditions due to economical and environmental considerations rendering them venerable to frequent failures. Voltage stability has become a major concern as the present system is operating near its maximum capacity level. To get information regarding voltage stability margin and its improvement, various methods has been used in past. This work deals with L-index and VCPI techniques to calculate the stability margin and give information about the weak areas of the network. By using L-index the settings of control strategies can be known and by making proper changes in these values the operator of ECC can avoid the unwanted situations. ANN is an intelligent tool with parallel computational capability. It can perform nonlinear mapping in short duration. Once neural network is trained, it provides acceptable recommendations in a short time, which is suitable for online application. Here ANN is used to predict the values of L-index, VCPI, and control Quantities (generator excitation and settings of SVCs), which become helpful to the operator for handling the unfavorable conditions. These methods are applied on IEEE-9 bus and IEEE-14 bus system. An attempt is made to find best results that the voltage stability margin can be assessed and improved.
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    ThesisItemOpen Access
    Performance analysis of self-excited induction generator using MATLAB & its experimental verification
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Choudhary, Monika; Goel, S.K.
    Self-excited induction generator offers certain advantages over a conventional synchronous generator as a source of isolated power supply. Main advantages are reduced cost, less maintenance, self protection from short-circuit or overload condition. It is used as variable speed generator for different application such as wind energy conversion, micro-hydro power generation. It can be used to generate constant voltage and frequency if the electrical load is maintained constant at its terminals. Under such operations, SEIG requires constant capacitance for excitation resulting in a fixed-point operation. In this thesis, Experimental investigation of Self-Excited Induction Generator has been done in laboratory. Three-phase SEIG model using Matlab simulink has been developed. MATLAB/Simulink software has been used to analyze the behavior of SelfExcited Induction Generator. Simulink result has been obtained using the developed model. Experimental investigation of Self-Excited Induction Generator condition under different loading conditions has been done using four channel digital oscilloscope. Experimental investigation of SEIG has been done in laboratory. The results obtained in laboratory are very much similar to the MATLAB results.
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    ThesisItemOpen Access
    Performance analysis of axially laminated anisotropic synchronous reluctance motor
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2005-07) Rawat, Harendra Singh; Banerjee, G.K.
    In an effort to obtain better performance of SRM by obtaining a high ratio of direct (d) axis to quadrature (q) axis magnetizing inductances ( d q L L ) an axially laminated anisotropic (ALA) rotor was designed and fabricated. To construct an ALA rotor the axially laminated segments were constructed with multiple C.R.G.O laminations interleaved with milo paper insulation sheets. The thickness of C.R.G.O lamination and milo paper insulation sheet were of .2 and .25 mm respectively. The rotor has been designed for four poles configuration. The objective of this study was to design and fabricate axially laminated anisotropic synchronous reluctance motor for performance analysis. Parameters of SRM determined by A.C stand still test. The saturation effect was studied by synchronous running test. We analyzed the steady state and dynamic state behaviour of the SRM by developing a mathematical model. The presence of third and fifth harmonic at no-load and load condition was also determined. The results reveal that the steady state analysis performance on simulated of SRM as well as experimentally on test motor were in close agreement. The saturation effect was found negligible in motoring mode. The harmonic contents included third and fifth harmonics in very small percentage and increased slightly with loading.
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    ThesisItemOpen Access
    Analysis of excessive unevenness in load curve characteristics due to solar energy incorporation into grid & the possible solution
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Bohra, Vijay; Arora, Sudha
    The global average temperature is rising at significant rate, so is our concern towards it. One of the major contributor to rising temperature, is the green house gases emitted from power sector due to its high dependence on conventional sources like coal and petroleum products. Various measures like incorporating renewable energy into system are being taken to reduce the share of conventional (fossil fuel based) plants in the energy sector. Among renewable sources, solar energy has the highest growth rate (24% growth) due to its universal acceptance features like availability of sun on earth surface, ease of maintenance, ease of installation, no moving parts, negligible pollution level etc. But, with high solar incorporation, a major problem which is foreseen for every country is significant dip in power requirements from conventional energy sources, resulting in dip in their load curve during day time which could decrease the efficiency of these conventional plants (mostly thermal plants) and leads to excessive curtailment of energy due to over generation. A need for such a system was felt where energy could be stored (acting load during peak hours) and released (when there is excessive ramp to reduce pressure from thermal power plants). So, the missing link was searched and energy storage system was found to be a possible solution to the above mentioned problems. Among options like pumped hydro storage, compressed air storage, and battery energy storage, battery energy storage system can be best solution because of its wide availability and applicability. Taking all these things into account, the first part of this thesis work deals with analysis of, unevenness in load curve due to solar energy incorporation. For this, load is varied in a way that resembles a typical load curve, on a SIMULINK model of grid-tied PV system, and the percentage share of load met by PV and grid are recorded and analysed. In the second part, a Battery Energy Storage System (BESS) is designed in SIMULINK as the solution to above problem.
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    ThesisItemOpen Access
    Advanced directional relaying schemes for series compensated transmission lines and distribution networks
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-07) Bisht, Dinesh Singh; Saxena, Ravi
    In integrated power systems the direction of fault current is not fixed. A reliable, effective and versatile directional relaying is therefore very important. Voltage and current inversion in series compensated lines leads to mal-operation of conventional directional relays. In distribution lines where potential transformer is generally absent, conventional directional relays cannot be used. This thesis presents two modified directional relaying schemes to address these shortcomings. First scheme utilise the phase change in positive sequence current and magnitude change in positive sequence voltage at fault and pre-fault conditions. It is evaluated through MATLAB simulation for a series compensated line and its performance is compared with conventional directional relaying for different type of fault. This proposed scheme addresses the problems of voltage and current inversion faced in conventional directional relaying. The second scheme utilise only the post fault current to estimate the fault direction. Hence, it is an attractive method of directional relaying in distribution networks but equally applicable for transmission lines. Performance of this technique was assessed using simulated models of transmission and distribution lines on MATLAB for different operating conditions; like change in the power flow direction, effect of fault resistance, effect of fault location, level of compensation etc.
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    ThesisItemOpen Access
    Modeling and performance analysis of PV module
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Sanjay Kumar; Saxena, Ravi
    Energy production from solar energy sources is accelerating due to increase in oil prices, depletion in fossil fuel reservoir and environment change concern. Solar energy is environment friendly, reliable, clean and most promising energy resource among renewable energy options. Photovoltaic module composed of the series and parallel connected solar cell to meet requisite level of voltage and current at consumer end. Photovoltaic module’s performances are mainly depends on environmental conditions such as irradiance and ambient temperature. The main emphasis of the thesis is to be placed on photovoltaic system, modeling and simulation of PV module. A PV module has been implemented in MATLAB/Simulink environment to predict modeled PV module performance. This thesis discusses the effect of temperature, irradiance level, series resistance and shunt resistance on the performance of modeled PV module.