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Subject: Electrical Engineering × End date: 2021 × Thesis Type: M.Tech. ×
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    ThesisItemOpen Access
    A fault classification and location detection technique for an overhead power transmission line using an Artificial Neural Network and FFT
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-02) Kohli, Vikram; Yadav, Abhishek
    The rapidly increasing need for energy in this modern competitive era has developed an increasing demand for power supply due to which an appreciable growth of power grid can be seen all over the world. A huge number of new transmission lines and distribution networks are being installed in the system to meet the demand. The main objective of this research is to study and design a fault locator that can detect, classify, and locate faults in power transmission lines. The most important aspect of this thesis is to concentrate on the analysis of the transmission line’s phase currents and voltages during various fault conditions. The pre-processing of fault voltages and current patterns is processed using Fast Fourier Transform (FFT) tool and the output of the FFT is provided to the ANN so that they can be used to create an efficient fault locator. When considering the physical parameters and the size of the transmission line, the accuracy with which the designed system detects the fault in power system becomes very important. A fault locator with satisfactorily high accuracy can easily achieved with the help of artificial neural networks using a large amount of data set for training and the testing processes. This eliminates the need for proficiency in power systems, which is a necessity when working with expert fuzzy systems. Hence, this thesis focuses on the design of a fault locator that can be even used by people who are not experts in the field of power systems. Analysis of neural networks with various combinations of hidden layers and neurons per hidden layer has been given to validate the choice of neural networks in each stage. Simulation results have been presented to illustrate that artificial neural network based methods are successful in locating faults on transmission lines. An accuracy of 100% to classify a fault and 98.5% to locate the fault was achieved.
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    ThesisItemOpen Access
    STATCOM based voltage and frequency regulator for self-excited induction generator
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-02) Ahmad, Tanveer; Srivastava, Ajay
    Self-excited induction generator (SEIG) belongs to the class of asynchronous electrical machines. SEIG offers many attractive features like low maintenance, absence of a separate dc excitation system, good transient performance, ruggedness of its cage rotor construction, reduced cost, brushless rotor, self-protection against short circuits etc. As a result, the self-excited induction generators are increasingly being used in grid-isolated areas, stand-alone wind power applications. Its market is rapidly expanding. Since the development of induction generators, problems were encountered for poor voltage and frequency regulations but in last decade, the continuing technological development in power electronics, microprocessors, semiconductor chips, have combined to provide reliable and efficient regulation at varying loads and varying speeds. In SEIG, the terminal voltage drops with load variation so the prime objective of closed loop control is to maintain the reactive power level almost constant irrespective of load changes. So closed loop is necessary in applications that demands better control and constant terminal voltage. The terminal voltage of the generator is compared with the reference voltage continuously. The voltage and frequency regulation of SEIG depends upon two factors. One is the excitation system and second is the control strategies. If excitation fails, control strategy is required to bring back the stable operation. Various types of control strategies have been proposed in the past for studying the behaviour of SEIG during dynamic & transient periods. This thesis comprises of simulation and STATCOM based control strategy with reference to voltage, frequency and current response under variable loading conditions at constant rotor speed. Simulations were performed in MATLAB/Simulink software. Simulation results concluded that at rated voltage of 480 V and speed 1800 RPM for selfexcited induction generator and at different loadings of 50 kW and 30 kW, an excellent voltage and frequency regulation was achieved through proper tuning and suitable gains of regulators of a 100 kVA, 480V STATCOM based controller. The stable operation of system was disturbed with load variation and it is successfully regained with the help of STATCOM controller.
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    ThesisItemOpen Access
    Assessment of groundwater quality for drinking and irrigation purposes in a part of Tons river basin
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-02) Pant, Shikha; Shiv Kumar
    The present study was conducted in a part of Tons river basin located in Dehradun district of Garhwal division of Uttarakhand. The sampling of groundwater of shallow aquifer was done at 16 locations in May 2012 and May 2019 by Central groundwater board, Dehradun and the collected groundwater samples were analyzed for 15 physico-chemical parameters. Piper plot was drawn to know the hydrochemical facies of the groundwater. Spatial distribution of 15 parameters was done with help of Kriging in ARC GIS. Factor analysis was applied to determine the dominating physico-chemical parameters contributing to the pollution of groundwater at a particular sampling site. Drinking water quality was assessed using BIS standards and drinking water quality index. The groundwater of the study area was also assessed for irrigation using irrigation water quality index, seven irrigation water quality parameters and the criteria given by Richard (1954), Wilcox (1955), Westcot and Ayers (1984). On the basis of this study, the piper plot diagram was found to be an easy and effective way to determine hydrochemical facies in groundwater. For both the years, most dominant hydrochemical facies was Ca2+-Mg2+-HCO3 -. On the basis of spatial distribution, the groundwater was found to be polluted at Gularghati, Purkulgaon, Majra, Bhatta and Baronwala. On the basis of factor analysis, it was concluded that the sampling sites Baronwala and Ramgarh were most polluted sampling sites. The groundwater at all the sampling sites in the study area was found suitable for drinking. According to the irrigation water quality index, the groundwater of the shallow aquifer in the study area should be used with low to moderate restrictions, with the exception of groundwater at Selaqui and Redapur for the year 2012 and Selaqui and Chorba for the year 2019 which should be used with a high restriction. On the basis of criteria given by Richard (1954), the groundwater at all the sampling sites was low to medium saline while alkalinity was found to be low at all sampling sites for both the years. On the basis of criteria given by Wilcox (1955), the groundwater was found to be under excellent, good or permissible class for irrigation, on the basis of percent sodium and EC for both the years. On the basis of criteria given by Westcot and Ayers (1984), the groundwater of the study area was found to have no effect or slight to moderate effect on the availability of water to the crops for both the years, while there was no effect on the sensitivity of the crops for both the years whereas severe effect on permeability of soil was found at six sampling sites, if the groundwater of the study area is used for irrigation.
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    ThesisItemOpen Access
    A methodology and comparative analysis of enhanced efficiency method using interleaved boost converter for maximum power point tracking in Solar PV System
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-02) Prashant Kumar; Saxena, Ravi
    This research study provides an efficient MPPT controller using different technique such as P&O, FLC, IC, MIC, and can be applied in a stand-alone PV system. It has been explained that when the solar PV module is directly connected to the load, the power delivered is not maximum and fluctuates due to variations in irradiance and temperature levels. Thus, an PV system is needed to achieve the optimum or peak power under changing environmental operating conditions. The dc-dc converter is then used in the Solar PV system along with MPPT controllers to achieve the optimum or peak power under changing environmental operating conditions. Modeling and simulation of each component of Solar PV system was presented and discussed in this research. These components were developed and simulated in a MATLAB/Simulink environment then all subsystems were connected together and combined with load to assess overall performance under varying weather operating conditions. The amount of output voltage ripple and input current ripple generated by conventional boost converter and two- phase IBC for different duty cycles was compared and analyzed.
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    ThesisItemOpen Access
    Modelling and power quality analysis of grid-connected PV system in real-time environment using typhoon HIL
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-02) Shah, Shubham; Arora, Sudha
    Renewable energy is playing a major role in present energy needs. This is also desirable due to the emerging demand for reducing greenhouse gases emission. The proposed work aims to model a three-phase grid-connected photovoltaic (PV) system in a real-time environment and analyses the power quality issues present in it. The work focuses on a string of PV modules that is optimized for maximum power transfer. A two-stage model is implemented where a boost converter is used integrated with maximum power point tracking (MPPT) algorithm. The output from boost converter is given to inverter which is tied with the grid using a phase-locked loop circuit. An uncoupled Watt-VAR control methodology is implemented for controlling the flow of injected power into the grid. Various PI controllers are tuned to give proper outcomes. This is followed by a mathematical analysis of simulated results. The validity of the proposed model is verified by the real-time simulation in Typhoon HIL software.
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    ThesisItemOpen Access
    Active & reactive power control in a 3-phase grid connected solar pv system by employing decoupled control scheme
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2020-12) Maithani, Himanshu; Goel, S.K.
    The proposed control scheme is efficient in controlling the flow of Active and Reactive power to the grid independently by maintaining the DC link voltage at a fixed value, irrespective of the source intermittency and ambient temperature conditions. The “Decoupled control scheme” employs two control loops to control the operation independently. So, by using the inner control loop it controls the power flow whereas, by using external control loop it maintains the DC link voltage at a constant level. Depending upon the converter topology and switching scheme the 3-phase power can be delivered to the grid with a THD value lower than specified value according to the IEEE standard. In the proposed scheme the triangular comparison based SPWM switching scheme is compared with the SVPWM switching scheme and also three-level multi-level DC/AC invertor topology (Diode Neutral Clamped invertor) is compared with the conventional two-level DC/AC convertor topology. The SVPWM switching scheme is efficient in generating 3- phase output with very low harmonic content and operates both in linear as well as overmodulation region as opposed to its SPWM switching scheme which operates only in linear modulation region i.e. m<1. Since, by using the proposed converter topology and switching scheme the majority of the low order harmonics would be be eliminated, the rest of the higher order harmonics can attenuated by inserting LCL passive filter between the three-phase grid and three phase invertor which consequently lead the output waveform very closer to the sinonosuidal waveform and consequently making the THD value as par IEEE standard. The proposed thesis work on the operation of the Decoupled Control scheme using MATLAB/Simulink software is performed under various temperature as well as irradiance conditions and also under varying conditions.
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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.