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Subject: Electrical Engineering × End date: 2021 × Type: Thesis ×
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    ThesisItemOpen Access
    Simulation, implementation and comparative analysis of control strategies for winddiesel generator system
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-03) Joshi, Hitesh; Swami, A.K.
    Renewable energy resources are considered as the best alternatives to conventional energy sources, worldwide. India is blessed with various renewable resources like solar, wind, biomass, hydro, tidal, etc. However, there is a large gap between demand and supply of electrical energy in India and many areas are still not having sufficient supply of electrical energy. A combination of renewable energy sources like wind-diesel available at any remote and isolated location, is sufficient for local energy demand. Installation of such hybrid systems are best solutions to provide sufficient electricity to remote and isolated villages for sustainable development. This research work focuses on the supply of power to the far distant loads where the grid is not feasible. The hybrid topology of wind-diesel is proposed to feed the local loads in isolated mode for rural electrification. Various control algorithms are implemented for satisfactory performance of this system under steady state and dynamic conditions. These algorithms provide voltage control, harmonics elimination, reactive power compensation and power balancing. The brushless generators such as, permanent magnet synchronous generator (PMSG) is used for power generation in remote areas as they are maintenance free. For the variable speed wind generation, the maximum power tracking (MPPT) is realized using perturb and observe (P&O) and tip speed ratio (TSR) approaches. The Battery Energy Storage System (BESS) is used to provide load leveling during wind fluctuations and load variations. Such hybrid systems provide power quality solutions and are able to maintain the power balancing. The diesel generator (DG) set is used with the renewable source so that during an outage when the renewable generation is not enough to meet the load demand, the DG is synchronized with the Point of Common Coupling (PCC) and starts feeding the local loads. In this way, the economic utilization of the fossil fuel resource is possible. This hybrid system is capable of supplying power to the remote places as well as to the cities during outage or emergencies. These controls are robust and are helpful in power management with power quality solutions. The satisfactory performances of these systems are demonstrated with simulation results obtained from models developed in MATLAB/Simulink environment.
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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
    Design, simulation and analysis of an improved EPLL based control technique with adaptive DC link voltage regulation for grid-connected solar PV system
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-03) Matiyali, Kanchan; Goel, S.K.
    Global electrical energy consumption is steadily increasing and there is a necessity to increase the power generation capacity. Conventional power generation schemes have serious environmental issues like climate change, high oil price, and water and oil pollution. The solution to these issues could be renewable energy (RE) sources, which eliminate the harmful emissions from the conventional sources. RE sources play an important role in overcoming the trepidation over energy crisis and environmental pollution in the world. Among all the renewable energy sources, solar energy is an imperious energy source that can deliver significant amount of electrical power with abundant solar potential. In recent years, increase in use of grid connected SPV system. These systems have the merits that apart from PV power consumed by the load, excess power is sent to the existing electrical grid. To provide effectiveness and to meet the required interconnecting standards controllers play a very important role and control techniques applied to grid connected inverters are gaining more importance. This thesis is an effort to development a proposed control technique to improve power quality of the system for grid-connected SPV system. To compensate active power injected into the grid, an improved enhanced phase lock loop (I-EPLL) control technique is used. The MATLAB/Simulink model is tested under various environmental and loading conditions. To reduce switching losses in the system, an adaptive DC link voltage regulation technique is used. The proposed control technique compensates for problems like power factor correction, current unbalance and current harmonics and also inject energy generated by solar PV to the grid with a very low THD even under nonlinear loading conditions.
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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
    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.