iosr-JEEE   Volume-9 ~ Issue-1 ~ Jan-Feb 2014

Abstract: This paper presents how multiple winding faults can be detected by Sweep Frequency Response Analysis (SFRA). The test methods used by the authors for presenting the results are described. The Short Circuited Turns Fault on HV "V" phase winding and Earth Fault on LV "V" phase winding have been practically simulated simultaneously on the 10 KVA, 11000 V / 440 V, 3-phase, 50 Hz, Dyn11 Power Transformer which is specially designed and developed in-house. The result of these simulated faults are presented and discussed. The SFRA data analysis is performed on three phase comparison basis and a conclusion has been drawn from it.

Keywords: Earth fault, Multiple winding fault, Power transformer, Short circuited turns fault, Sweep frequency response analysis.

[1] CIGRE Working Group A2.26, "Mechanical Condition Assessment of Transformer Windings Using Frequency Response Analysis (FRA)", Brochure 342, Paris, April 2008.
[2] Aradhana Ray, "Application of Signal Processing Techniques for Condition Monitoring of Electrical Equipment," Ph.D. thesis, Dept. of Electrical Engineering, Univ. M.S., College Faculty of Technology & Engineering, September 2009.
[3] IEC 60076 – 18 Ed.1: Power Transformer Part – 18, "Measurement of Frequency Response", United Kingdom, July 2012.
[4] A. Kraetge, M. Kruger, J. L. Velasquez, H. Viljoen, A. Dierks, "Aspects of the Practical Application of Sweep Frequency Response Analysis (SFRA) on Power Transformer", 6th Southern Africa Regional Conference CIGRE 2009.
[5] G. Matthew Kennedy, Charles Sweetser and Tony McGrail, "Field Experiences with Sweep Frequency Response Analysis", Doble Engineering Company – 73rd Annual International Doble Conference, 2006
[6] IEEE PC 57.149 Guide for the Application and Interpretation of Frequency Response Analysis for Oil Immersed Transformer, March 2013

Abstract: This paper proposes a method that estimates rotor position by using an unknown input observer over a full speed range. In this method, a trapezoidal back emf is modeled as an unknown input and the proposed unknown input observer estimating line to line back emf in real time makes it possible to detect the rotor position. This observer has high performance even at low speed range because rotor position is calculated independently of the rotor speed without adding any additional circuit or complicated operation process. Simulations have been carried out for the verification of proposed control scheme. MAT LAB/SIMULINK model is used for software simulation.

Keywords-BLDC motor, Four quadrant operation, sensorless control, full speed range, unknown input observer.

[1] C. Sheeba Joice, S. R. Paranjothi, and V. Jawahar Senthil Kumar, "Digital Control Strategy for Four Quadrant Operation of Three Phase BLDC Motor With Load Variations,", IEEE Transactions On Industrial Informatics, Vol. 9, No. 2, May 2013.
[2] Tae-Sung Kim, Byoung-Gun Park, Dong-Myung Lee, Ji-Su Ryu, and Dong-Seok Hyun, " A New Approach to Sensorless Control Method for Brushless DC Motors", International Journal of Control, Automation, and Systems, vol. 6, no. 4, pp. 477-487, August 2008.
[3] N. Matsui, "Sensorless PM brushless DC motor drives," IEEE Trans. on Industrial Electronics, vol. 43, no. 2, pp. 300-308, 1996.
[4] K. Xin, Q. Zhan, and J. Luo, "A new simple sensorless control method for switched reluctance motor drives," KIEE J. Electr. Eng. Technol., vol. 1, no. 1, pp. 52-57, 2006.
[5] S. Ogasawara and H. Akagi, "An approach to position sensorless drive for brushless DC motors," IEEE Trans. on Industry Applications, vol. 27, no. 5, pp. 928-933, 1991.
[6] J. C. Moreira, "Indirect sensing for rotor flux position of permanent magnet AC motors operating over a wide speed range," IEEE Trans. on Industry Applications, vol. 32, no. 6, pp. 1394-1401, 1996.

Abstract: Voice recognition is an expanding trend nowadays for automation. As speech is the preferred mode of operation for human being, this paper highlights the importance of human voice that activates electrical appliances at home in wireless environment. The user makes use of voice commands to perform certain actions such as switching the lights ON/OFF and regulating the speed of appliances. This system plays an important role for the elderly and physically disables people to control their appliances in intuitive and flexible way. The graphical user interface (GUI) system is developed using LabVIEW. LabVIEW is a highly productive development environment that interacts with real-world data for creating custom applications. So the method of control of electrical appliances is implemented using LabVIEW. With this voice recognition technique accuracy of more than 90% is achieved.

Keywords: Automation, Voice recognition, LabVIEW, ON/OFF control, Speed regulation.

[1]       Richard.C, Simpson and Simon.P.Levine, “Voice Control of a Powered Wheelchair”, IEEE Trans. Neural systems and Rehabilitation Engineering, vol. 10, no. 2, pp. 122-125, June 2002.
[2]       Laisa.C.P, Nichholas S. Almeida, Ana G. D. Correa, Roseli D.Lopes, Marcelo K.Zuffo, “Accessible Display Design to Control Home Area Networks”, IEEE Trans. Consumer Electronics, Vol.59, No.2, pp. 422-427, 2013.
[3]       Mark S. Hawley, Stuart P. Cunningham, Phil D. Green, Pam Enderby, Rebecca Palmer, Siddharth Sehgal, and Peter O’Neill, “A Voice-Input Voice-Output Communication Aid for People with Severe Speech Impairment”, IEEE Trans. Neural systems and Rehabilitation engineering, vol. 21, no. 1, pp. 23-31, , Jan 2013.

Abstract: Power supply voltages in digital systems have been reduced considerably in recent years and often digital components requiring different voltages are present in the same board. This has increased the demand for multiple output power distribution systems with tight load regulation. In this paper, a detailed analysis and design of a multi-output push-pull zero voltage switching (ZVS) quasi resonant converter (QRC) has been carried out. Also simulation of multi-output push-pull zero voltage switching (ZVS) quasi resonant converter (QRC) has been carried out using Matlab/SIMULINK software. The proposed converter is suitable for aerospace applications.

Keywords: dc-dc converters, push-pull converter, quasi-resonant converters, Zero voltage switching.

[1] Liu K.H. and LEE F.C.Y., Zero-voltage Switching Technique in DC-Dc Converters, IEEE Specialists Conference Record,
1986,pp.58-70.
[2] I.Barbi, J.C.Bolacell,D.C.Martins and F.B.Libano, Buck Quasi-Resonant Converter operating at Constant Frequency:Analysis,
Design and Experimantation,IEEE,pp.873-880.
[3] Wildon C.P., de Aragao Filho,I.Barbi, A Comparison Between Two Current-Fed Push-Pull DC-DC Converters-Analysis,Design
and Experimentation, IEEE, 1996, pp.313-320.
[4] Grover V., T.Bascope and I.Barbi, Isolated Flyback-Current-Fed Push-Pull Converter For Power Factor
Correction,IEEE,1996,pp.1184-1190.
[5] B.Swaminathan and V.Ramanarayanan, A Novel Resonant Transition Push-Pull DC-DC Converter,J.Indian Inst Sci,Nov.-
Dec.2004,pp.217-232.

Abstract: Distributed Energy Storage (DES) systems are a potential alternative to balance any instantaneous mismatch between supply and demand in the Smart Grid (SG). Optimization of location and sizing of DES uses analytical method which reduces the gain energy loss but it does not consider the cost. In this work, the medium voltage SG including Distributed Generation (DG) unit along with the DES system is taken. Controller based on Neural Network is used as solution procedure for the problem in optimal sizing and location of DES. The proposed work intends to offer a useful tool for analyzing potential advantage of distributed energy storage in SG for both different possible regulatory schemes and services that are provided.

[1] AlaaMohd, EgonOrtjohann, Andreas Schmelter, NedzadHamsic, Danny Morton, "Challenges in Integrating Distributed Energy Storage Systems into Future Smart Grid", IEEE Transaction, 2008.
[2] AnvariMoghaddam.A, A.R. Seifi, "Study of forecasting renewable energies in smart grids using linear predictive filters and neural networks", IET Renewable Power Generation., Vol. 5, Iss. 6, pp. 470–480, April 2011.
[3] Benjamin Kroposki,P.K. Sen, Keith Malmedal, "Optimum Sizing and Placement of Distributed and Renewable Energy Sources in Electric Power Distribution Systems", IEEE Transaction, 2013.
[4] G.Celli, S. Mocci, F. Pilo, and M. Loddo "Optimal Integration Of Energy Storage In Distributed Networks", IEEE Bucharest Power Tech Conference, 2009.

Abstract: A multiplier is one of the key hardware blocks in most digital and high performance systems such as FIR filters, digital signal processors and microprocessors etc. many researchers have tried and are trying to design multipliers which offer either of the following- high speed, low power consumption, less area, more accuracy or even combination of them in multiplier.

[1] J.N. Mitchell, Computer multiplication and division using binary logarithms, IRE Transactions on Electronic Computers EC-11
(1962) 512–517.
[2] Z. Babić, A. Avramović, P. Bulić. An iterative logarithmic multiplier Microprocessors and Microsystems, Volume 35, Issue
1, February 2011, Pages 23-33
[3] D.J. McLaren, Improved Mitchell-based logarithmic multiplier for low-power DSP applications, in: Proceedings of IEEE
International SOC Conference 2003, 17–20 September 2003, pp. 53–56.
[4] V. Mahalingam, N. Rangantathan, Improving accuracy in Mitchell's logarithmic multiplication using operand decomposition, IEEE
Transactions on Computers 55 (2) (2006) 1523–1535.
[5] E.L. Hall, D.D. Lynch, S.J. Dwyer III, Generation of products and quotients using approximate binary logarithms for digital filtering
applications, IEEE Transactions on Computers C-19 (2) (1970) 97–105.

Abstract: Recrystallized silicon solar cells using microwave annealing will require adequate modelling of microwave power distribution to predict the uniformity of re-crystallization of silicon, specially at high temperatures. Since, recrystallization will have to be carried out of doped silicon, doping dependence of such processes at high temperatures is also very important. This work reports modelling results for temperature and doping dependence of microwave spatial power distribution in c-Si wafer during microwave annealing. Temperature dependence was introduced through bandgap, effective mass and lattice scattering terms in Drude model of free-carrier concentration.

[1] S. D. Das, Prospects of Microwave Heating in Silicon Solar Cell Fabrication – A Review, IOSR-JEEE, 6(3), 2013, 28-38.
[2] R. N. P. Vemuri, M. J. Garde, N. D. Theodore, and T. L. Alford, Dopant Activation in Arsenic -Implanted Si by Susceptor-Assisted Low-Temperture Microwave Anneal, IEEE Electron Device Letters 32 , 2011, 1122-1124.
[3] J. N. Lee, Y. W. Choi, B. J. Lee and B. T. Ahn, Microwave-induced low-temperature crystallization of amorphous silicon thin films, Journal of Applied Physics, 82(6), 1997, 2918-2921.
[4] S. D. Das, Full wafer 3D modelling of power distribution during microwave annealing of doped c-Si, IOSR-JEEE, 9 (1-IV), 2014, 68-76.
[5] T Basak, Role of lateral and radial irradiations on efficient microwave processing of food cylinders, Chemical Engineering Science, 62, 2007, 3185 – 3196.

Abstract: Smart Grid (SG) is a modernization of electric system through the integration of new age information technologies, new strategic public policies and allows for the new uses of the electric grid, both in operations and through new customer side applications, that extract the benefits of more efficient operation, more efficient use of grid assets and more cost-effective expansion of the electric grid. A solar system is connected for the household purposes. The maximum power is obtained using MPPT algorithm as previously and for a satisfactory operation of whole system there is no control strategy was developed. But, here Neural Network (NN) control scheme is used for satisfactory operation of the whole system. NN is used in the control scheme for MPPT gate drive and dc load priority. For this application MATLAB/ Simulink software is used.

[1] R. Strzelecki and G. Benysek, Power Electronics in Smart Electrical Energy Networks. London, U.K.: Springer, 2008.
[2] R. Zogg, T. Lawrence, K. Roth, and J. Brodrick, "Residential emergency power systems," Ashrae J., vol. 48, pp. 68–70, Oct. 2006.
[3] W. Kramer, S. Chakraborty, B. Kroposki, and H. Thomas, "Advanced power electronic interfaces for distributed energy systems, part 1: Systems and topologies," National Renewable Energy Laboratory, Tech. Rep. No. NREL/TP-581-42672, Mar. 2008.
[4] H. Jiayi, J. Chuanwen, and X. Rong, "A review on distributed energy resources and MicroGrid," Renewable Sustainable Energy Rev., vol. 12, pp. 2472–2483, 2008.
[5] G. Pepermans, J. Driesen, D. Haeseldonckx, R. Belmans, and W. D'haeseleer, "Distributed generation: Definition, benefits and issues," Energy Policy, vol. 33, pp. 787–798, 2005.
[6] J. A. P. Lopes, N. Hatziargyriou, J. Mutale, P. Djapic, and N. Jenkins, "Integrating distributed generation into electric power systems: A re-view of drivers, challenges and opportunities," Elec. Power Syst. Res., vol. 77, pp. 1189–1203, Jul. 2007.
[7] K. George, "DC power production, delivery and utilization," Electric Power Research Institute. Palo Alto, CA, Jun. 2006, White Paper.