Faculty Publications
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Item Design of haul road lighting system. Part III: Application(2006) Karmakar, N.C.; Mangalpady, M.; Rao, Y.V.; Yaragatti, U.R.The design of haul road illumination systems based on a scientific approach is very important. Improperly planned lighting systems may provide unsatisfactory illumination and may also incur higher costs. This paper describes illumination systems designed for two haul roads using the computer programs developed in earlier stages of this work. System performances and cost are compared with the existing illumination system. Designs based on the developed programs show total potential cost savings of approximately 26% and 48% for the two systems.Item Modelling and simulation of a wind/diesel hybrid power system(2006) Kini, A.S.; Yaragatti, U.R.In remote and isolated areas far from the grid, it may not be an economically viable option to supply electric power from the grid. This is due to the high cost of transmission lines and higher transmission losses that accompany distribution of centrally generated power to remote areas. In such cases hybrid systems such as wind/diesel generators are found to be the most reliable, preferred and attractive alternative source of power supply. This paper presents the modelling and performance analysis of wind/diesel hybrid generating system. To regulate the frequency and voltage output of the wind generator, an AC-DC-AC scheme using SPWM technique is employed. To evaluate the performance and stability of the hybrid system, it is simulated for different disturbances involving variation in wind speed and load conditions using EMTDC/PSCAD software.Item Efficient artificial lighting system for surface mine haul roads(2006) Mangalpady, M.; Yaragatti, U.R.Haul roads within the pit are one of the critical areas in surface mines where lighting installations are not permanent due to regular advancement of the working face. Due to this reason it is very difficult to maintain the lighting standards, as specified by various regulatory bodies. Lighting in mines presents special problems because of the dark surroundings and low surface reflectance. Hence, scientific design of artificial lighting is very important to achieve the minimum required lighting standards. Authors developed software, named SURLux, in MATLAB for design of illumination system, which incorporates all the design parameters. It also computes the total cost of the lighting system. In this paper a 1.0 km stretch of haul road is designed for four different types of sources namely, 150 and 250 W high pressure mercury vapor lamps (HPMV), and 150 and 250 W high pressure sodium vapor lamps (HPSV), at various pole heights (8, 10, 12, 14 and 16 m). From the results of the study it is observed that with 16 m height pole the total annual cost for 150 W HPSV is the minimum (Rs. 87,739/-). In most of the cases the cost is high with HPMV lamps. This is mainly because of their shorter life and relatively more number of poles. In general, lamp selection is made mainly based on efficacy and suitability to each situation. However, among the feasible alternatives for any project, the variant that offers the minimum total cost is finally selected. © 2006 IEEE.Item Modelling and performance analysis of a wind/diesel hybrid power system(2006) Kini, A.S.; Yaragatti, U.R.Domestic consumers in the remote places who are not connected by the main electrical grid network, hybrid systems such as wind/diesel generators have been considered as the most reliable, preferred and attractive alternative source of power supply. This paper presents the modeling and performance analysis of wind/diesel hybrid generating system. To regulate the frequency and voltage output of the wind generator, an AC-DC-AC scheme using SPWM technique is employed. The system is simulated for different wind speed and load conditions using EMTDC/PSCAD software. © 2006 IEEE.Item Electrification in rural areas of India and consideration of SHS(2010) Kamalapur, G.D.; Yaragatti, U.R.Rural electrification is an integral component of poverty alleviation and rural growth of a nation. In India, electricity has not played effective role in the socio-economic growth of village. Government of India has ambitious target of providing electricity to all villages by 2008 and all rural households by 2012. Steps are initiated with Rural Electric Corporation, State Electricity Boards, Reforms in Power sector. Ever increasing demand of electrical energy is causing a large gap in generation and load demand. All the requirement of energy cannot be fully met with conventional grid supply so, an alternative energy source has to be found out for this purpose. Therefore it has become necessary to explore the applications of distributed energy sources which are inevitable to meet the energy requirements. An attempt has been made in this paper to assess the features of rural electrification in India and a simple cost comparison of Solar Home Systems (SHS) with grid supply in deep rural areas. ©2010 IEEE.Item Solar PV- diesel hybrid energy system for rural applications(2010) Mandi, R.P.; Yaragatti, U.R.This paper describe sizing of solar PV, DG set and battery bank for different configurations for share of solar power. Different configurations for integration of solar with diesel energy systems are explained in detail. The energy availability and reliability of the integrated energy system are highlighted The economics for implementation of different configurations are dealt with detailed discussion in this paper. ©2010 IEEE.Item Enhancing energy efficiency of auxiliary power system in a 210 MW coal fired power plant through energy efficiency(2010) Mandi, R.P.; Seetharamu, S.; Yaragatti, U.R.This paper describes the results of energy conservation measures in various thermal power plants spread over the country. Energy savings in various major auxiliaries are summarized here with improved performance. Staggering of auxiliary loads, reduction in hydrodynamic resistance of pipes and ducts, adoption of new energy efficient technologies, efficient control techniques, reduction in furnace ingress and monitoring of coal size at mill inlets will lead to substantial amount of energy savings. The energy conservation schemes are economically attractive with a break even period of 1 to 5 years. ©2010 IEEE.Item FPGA based control model with derivative filter for converter(2010) Veeranna, S.B.; Yaragatti, U.R.; Beig, A.R.In this paper, the control model for a digitally controlled DC-DC converter is presented along with derivative filter. The digital implementation of this model gives the detailed description about the gain and phase responses of each block in the digital controller loop. Key problems such as quantization resolution of digital pulse width modulator (DPWM), steady state limit cycle oscillations and loop delay of the controller are discussed and solutions are presented. The controller is implemented in an altera Quartus II 9.0 tool and simulated with an inbuilt simulator. It is observed that the controller utilizes less resource and consumes less power, means that the controller cost can be reduced. ©2010 IEEE.Item Synchronized SVPWM algorithm for overmodulation region for three-level VSI(2010) Veeranna, S.B.; Yaragatti, U.R.; Beig, A.R.Synchronization is essential for the satisfactory operation of VSI in high power applications. With proper selection of switching states it is possible to obtain synchronization and symmetry in space vector pulse width modulation (SVPWM) algorithm. A novel SVPWM based switching algorithm, which results in improved THD and increased fundamental voltage in overmodulation region by maintaining synchronization and symmetry is presented in this paper. A simple method to determine the switching sequence to achieve synchronization, quarter wave symmetry, half wave symmetry and three phase symmetry in overmodulation region is presented. The proposed algorithm is simulated and its performance in terms of the THD and magnitude of fundamental voltage of output is studied in the overmodulation region. The results show the improved performance of the proposed algorithm compared to the existing algorithms. The proposed algorithm is verified experimentally on a constant v/f three level VSI fed induction motor drive. © 2010 IEEE.Item Performance analysis of PWM strategies for cascaded H-bridge three-level inverter(2011) Veeranna, S.B.; Beig, A.R.; Yaragatti, U.R.Multilevel inverters with various pulse width modulation strategies have established their importance in high power high performance industrial applications, as they can synthesize output waveform with improved harmonic spectrum. This paper presents the performance analysis and comparison of different PWM strategies for cascaded H-bridge three-level inverter in terms of line voltage and motor current THD with their fundamental components. It is shown that harmonic loss minimized optimal-SHEPWM strategy gives better results in terms of voltage THD compared to SPWM, SVPWM and SHEPWM strategies. © 2011 IEEE.