iosr-JEEE   Volume-7 ~ Issue-3

Abstract: Harmonics are multiples of the fundamental frequency of power system. These harmonics are creating distorted voltages and currents in the power system. Distortion of voltages and currents can affect the power quality. This article covers Harmonics sources in power system. Different Sources of harmonics in power system have been discussed.

Keywords: Current, Distortion, Frequency, Harmonics, Power System, Source, Voltage

[1] C. Francisco and R. DeLa, "Harmonics and Power Systems", CRC Press Taylor & Francis Group, LLC, 2006
[2] K. D. Patil and W. Z. Gandhare, "Effects of Harmonics in Distribution Systems on Temperature Rise and Life of XLPE Power Cables", Power and Energy Systems (ICPS), pp. 1 - 6, Chennai, 22-24 December 2011
[3] J. Arrillaga, D. A. Bradley and P.S. Bodger, "Power System Harmonics", John Wiley & Sons, New York, 1985
[4] R. D. Henderson and P. J. Rose, "Harmonics: The Effects on Power Quality and Transformers", Industry Applications, IEEE Transactions, Vol. 30 , Issue: 3, pp. 528 - 532 , May/June 1994
[5] M. Rashid, "Power Electronics: Circuits, Devices, and Applications", 3rd Edition, Prentice Hall New Jersey, USA, 2004
[6] Variable Frequency Drive by Carrier Corporation Syracuse, New York, October 2005

Abstract: The output power of the present wind turbine is continuously increasing. Due to this Double fed Induction generators are gaining more attention especially in the field of wind power generation due to many advantages and rapid development in both power electronics and control strategies. Vector Control of doubly fed induction generator for variable speed wind power generation is used widely now days. The Control scheme used is stator flux oriented control for rotor side converter control and grid voltage vector control for grid side converter control for the control of active and reactive powers of the DFIG under variable speed operation. The scheme implemented uses Conventional PI controllers as well as Fuzzy logic controllers for the rotor side converter control to control active and reactive power and optimize the power generation from the DFIG. Here the design of a doubly fed induction generator (DFIG), using back-to-back PWM converters in the rotor circuit has been described. A vector-control scheme results in independent control of active and reactive powers, while ensuring sinusoidal supply currents. The scheme provides a wide speed-range operation from sub synchronous to super-synchronous modes.

Index Terms: windpower generation, fuzzylogic, DFIG

[1] Variable structure control of active and reactive power of DFIG in wind turbine,DONGYOUNGCHWA and KYO-BEUM-IEEE-2010
[2] Decoupled active and reactive power control of DFIGA.DENDUOGA,R.ABDESSEMED,M.L.BENDAAS,A.CHAIBA-2010-MEDITERRANEAN CONFERENCE
[3] Active and Reactive power control of DFIG using SVPWM converter AHMADI, H.LIVANI,H.KIRMANI-NOSHIRVANI-2009
[4] Modelling and control of wind turbine driven DFIG, A.TAPIA,G.TAPIA IEEE-2003 edition
[5] Power electronics and AC drives by BIMAL.K.BOSE Pearson edition -2002
[6] A Novel approach of direct active and reactive power control allowing the connection of the DFIG of the grid-JEBALI-BEGHOR BAMANEL,ARBIJIHEN SALMAN-BELKHODIA ILEM-2011

Abstract: Different electric wind power conversion systems structures can be used based on the converters topologies. A Wind Energy Conversion System (WECS) differs from a conventional power system. The power output of a conventional power plant can be controlled whereas the power output of a WECS depends on the wind. This nature of WECS makes it difficult for analysis, design and management. Various approaches have been developed to study the behavior of WECS. In this paper, the steady state characteristics of a WECS using doubly fed induction generator (DFIG) is analysed using MATLAB. The dynamic steady-state simulation model of the DFIG is developed using MATLAB. Simulation analysis is performed to investigate a variety of DFIG characteristics, including torque-speed, real and reactive-power over speed characteristics. Based on the analysis, the DFIG operating characteristics are studied. Keywords: Wind Energy Conversion System (WECS), Doubly Fed Induction Generator (DFIG), Simulation, MATLAB

[1] PATEL, M. R. : Wind and Solar Power Systems, CRC Press, 1999, pp. 82–83.

[2] ZAVADIL, R.—MILLER, N.—ELLIS, A.—MULJADI, E. : IEEE Power & Energy Magazine 3 No. 6 (Nov 2005).

[3] BANSAL, R. C.—BHATTI, T. S.—KOTHARI, D. P. : Bibil- iography on the Applications of Induction Generators in Non Conventional Energy Systems, IEEE Transactions on Energy Conversion 18 No. 3 (Sep 2003), 433–439.

[4] DATTA, R.—RANGANATHAN, V. T. : Variable-Speed Wind Power Generation Using Doubly Fed Wound Rotor Induction Machine — A comparison With Alternative Schemes, IEEE Transactions on Energy Conversion 17 No. 3 (Sep 2002), 414–421.

[5] TENNAKOON, A. P.—ARULAMPALAM, A.—EKANAYA- KE, J. B.—ABEYERATNE, S. G. : Modelling and Control of DFIGs for Wind Energy Applications, First International Con- ference on Industrial Information Systems, Aug 2006, pp. 8–11.

[6] EKANAYAKE, J. E. : Dynamic Modeling of Doubly Fed In-duction Generator Wind Turbines, IEEE Transactions on Power Systems 18 No. 2 (May 2003), 803–809.

[7] POTAMIANAKIS, E. G.—VOURNAS, C. D. : Aggregation of Wind Farms in Distribution Networks, European Wind Energy Conference and Exhibition, Madrid, June 2003.

[8] FEIJOO, A. E.—CIDRAS, J. : Modeling of Wind Farms in the Load Flow Analysis, IEEE Trans. on Power Systems 15 No. 1 (Feb 2000), 110–115.

[9] KAVASSERI, R. G. : Steady State Analysis of an Induction Generator Infinite Bus System, Proc. IASTED International Conf. on Power and Energy Systems, Marbella, Spain, 2003.

[10] JOHNSON, G. L. : Wind Energy Systems, Prentice-Hall, Upper Saddle River, NJ, 1985.

Abstract: A simple transmission line model for a patch antenna on a metameterial substrate is proposed. The results are compared with those from FDTD model and found to have reasonable matching.

Keywords: FDTD; Metamaterial; Microstrip Antenna; Transmission Line Model

[1] K. P. Prokopidis, T. D. Tsiboukis, "The Effect of Substrate Dispersion on operation of square microstrip antennas," IEEE Trans. On Mag., Vol. 42, No. 4, pp. 603-606, 2006.
[2] S. N. Makarov, S. D. Kulkarni, A. G. Marut, L. C. Kempel, "Method of moments solution for a printed patch/slot antenna on a thin finite dielectric substrate using the volume Integral equation," IEEE Trans. On Ant. & Prop., Vol. 54, No. 4, pp. 1174-1184, 2006.
[3] R. W. Ziolkowski, A. Erentok, "Metamaterial-based efficient electrically small antennas," IEEE Trans. On Ant. & Prop., Vol. 54, No. 7, pp.2113–2130, 2006.
[4] C. A. Balanis, Antenna Theory: Analysis and Design, 2nd ed. New York: Wiley, 1997.

Abstract: This paper proposes Improving of ATC is an important issue in the current de-regulated environment of power systems. The Available Transfer Capability (ATC) of a transmission network is the unutilized transfer capabilities of a transmission network for the transfer of power for further commercial activity, over and above already committed usage. Power transactions between a specific seller bus/area and a buyer bus/area can be committed only when sufficient ATC is available. Transmission system operators (TSOs) are encouraged to use the existing facilities more effectively to enhance the ATC margin. Heavily loaded circuits and buses with relatively low voltages can limit ATC usually. It is well known that FACTS technology can control voltage magnitude, phase angle and circuit reactance. Using these devices may redistribute the load flow, regulating bus voltages. Therefore, it is worthwhile to investigate the impact of FACTS controllers on the ATC. In this thesis focuses on the evaluation of the impact of TCSC and SVC as FACTS devices on ATC and its enhancement during with and without line outage cases. In a competitive (deregulated) power market, optimal the location of these devices and their control can significantly affect the operation of the system and will be very important for ISO. Keywords: FACTS devices, Available Transfer Capability, TCSC, Genetic Algorithm

[1] Transmission Transfer Capability Task Force, "Available transfer capability definitions and determination," North American
Electric Reliability Council, NJ, June 1996.
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FACTS devices", IEE Proc. Gener. Transm. Distrib., VO1.143, No.5, Sept. 1996, 447-454.
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[5] 1996. North American Electric ReliabilityCouncil. Available transfer capability Definitions and determination.
[6] Wang Feng,G.B.Shrestha "Allocation of TCSC Devices to optimize Total Transmission Capacity in Competitive Power
Market"IEEE Trans.Power systems,feb2001,587-592
[7] Transmission Transfer Capability Task Force,"Available transfer capability Definitions and determination",North American
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Abstract: In this paper, a direct ac-to-dc power converter is proposed for efficient energy harvesting from the low voltage inertial micro generators. The conventional power converters use diode bridge rectifiers and condition the micro generator outputs in two stages. Hence, they are inefficient and may not be a feasible option for very low voltage micro generators. Moreover, they are not conducive for optimum energy harvesting. The proposed converter avoids the use of bridge rectifiers, and directly converts the ac input to the required dc output. This converter uses a boost converter and a buck-boost converter to process the positive and negative half cycles of the ac input voltage, respectively. Furthermore, using this converter, maximum energy harvesting can be implemented effectively. Analysis of the converter is carried out. Based on the analysis, two schemes are proposed to control the converter. Design guidelines are presented for selecting the converter component and control parameters. A self-starting circuit is proposed for independent operation of the converter. Simulation results are presented to validate the proposed converter topology and control scheme.

Key words: AC–DC conversion, boost converter, energy harvesting, low power, low voltage, power converter control.

[1] J. A. Paradiso and T. Starner, "Energy scavenging for mobile and wireless electronics," IEEE Pervasive Comput., vol. 4, no. 1, pp. 18–27, Jan./Mar. 2005.

[2] S. Meninger, J. O. Mur-Miranda, R. Amirtharajah, A. P. Chandrakasan, and J. H. Lang, "Vibration-to-electric energy conversion," IEEE Trans. Very Large Scale Integr. Syst., vol. 9, no. 1, pp. 64–76, Feb. 2001.

[3] M. El-Hami, P. Glynne-Jones, N. M. White, M. Hill, S. Beeby, E. James, A. D. Brown, and J. N. Ross, "Design and fabrication of a new vibrationbased electromechanical power generator," Sens. Actuators A: Phys., vol. 92, pp. 335–342, 2001.

[4] T. M. Thul, S. Dwari, R. D. Lorenz, and L. Parsa, "Energy harvesting and efficient power generation from human activities," in Proc. Center Power Electron. Syst. (CPES) Semin., Apr. 2007, pp. 452–456.

[5] N. G. Stephen, "On energy harvesting from ambient vibration," J. Sound Vibrations, vol. 293, pp. 409–425, 2006.

Abstract: The hypothesis that when listening to speech in fluctuating maskers, CI users can not fuse the pieces of the message over temporal gaps because they are not able to perceive reliably the acoustic landmarks introduced by obstruent consonants (e.g., stops). To test this hypothesis, CI users were first presented with sentences containing clean obstruent segments, but corrupted sonorant segments (e.g., vowels). The other experiment investigated the hypothesis that envelope compression smears acoustic landmarks which signify syllable/word boundaries. To test this, CI users were presented with noise-corrupted stimuli processed using logarithmic compression during voiced segments and a weakly-compressive mapping function during unvoiced segments. All patients were profound-totally deaf, adults with a post lingual onset of impairment. The data support the efficacy of a feature extraction coding system where specific formant and amplitude information are transmitted via direct electrical stimulation to the cochlea. To examine the hypothesis that the newer generations of cochlear implants could provide considerable speech understanding to late-implanted, prelingually deaf adult patients..

[1] J. G. Bernstein and K. W. Grant. Auditory and auditory-visual intelligibility of speech in fluctuating maskers for normal-hearing and hearing-impaired listeners.J. Acoust. Soc. Am., 125:3358–3372, 2009.
[2] M. Dorman and P. Loizou. Relative spectral change and formant transitions as cues to labial and alveolar place of articulation. J. Acoust. Soc. Am., 100:3825–3830, 1996.
[3] M. Dorman, M. Studdert-Kennedy, and L. Ralphael. Stop consonant recognition: Release bursts and formant transitions as functionally equivalent context-dependent cues. Percept. Psychophys., 22:109–122, 1977.
[4] L. M. Friesen, R. V. Shannon, D. Baskent, and X. Wang. Speech recognition in noise as a function of the number of spectral channels: comparison of acoustic hearing and cochlear implants. J. Acoust. Soc. Am., 110:1150–1163, 2001.
[5] Q. J. Fu and R. V. Shannon.Effects of amplitude nonlinearity on speech recognition by cochlear implant users and normal-hearing listeners. J. Acoust. Soc.Am., 104:2571–2577, 1998.
[6] Q.J. Fu and R. V Shannon. Effect of acoustic dynamic range on phoneme recognition in quiet and noise by cochlear implant users.Percept.Psychophys. 06:L65–L70, 1999.
[7] K. Kasturi and P. Loizou. Use of s-shaped input-output functions for noise suppression in cochlear implants. Ear Hear., 28(3):402–411, 2007.
[9] N. Li and P. Loizou. The contribution of obstruent consonants and acoustic landmarks to speech recognition in noise. J. Acoust. Soc. Am., 124(6):3947–3958, 2008.
[10] N. Li and P. Loizou. Effect of spectral resolution on the intelligibility of ideal binary masked speech. J. Acoust. Soc. Am., 123(4):59–64, 2008..

Abstract: Fractional order controller is widely used in most areas of science and engineering, being recognized its ability to yield a superior control in many dynamical systems. This work proposes the applications of a Fractional Order PID (FOPID) controller in the area of Power Electronics for a DC-DC power converter to evaluate the use of Fractional Order PID controller with soft computing techniques. To design Fractional Order PID controller is to determine the two important parameters λ (integrator order) and μ (derivative order). In this article that the response and performance of Fractional Order PID controller is compared with closed loop conventional PID controller. In all the cases the Fractional Order PID controller much better than conventional PID controller for the given system.

Keywords:- Conventional PID, Cuckoo search, DC-DC converter, FOPID, Particle Swarm optimization

1] J. Alvarez-Ramirez, I. Cervantes, G. Espinosa-Perez, P. Maya, and A. Morales, A stable design of PI control for DC–DC converters with an RHS zero, IEEE Trans. Circuits Syst. I, Fundam. Theory Appl., 48(1), 2001, 103–106.

[2] B.M. Vinagre, C.A. Monje, A.J. Calder´on, J.I. Suarez, Fractional PID controllers for industry application: a brief introduction, Journal of Vibration and Control, 13(),2007,1419-1429.

[3] A.J. Calder´on, B.M. Vinagre, V. Feliu, Fractional order control strategies for power electronic buck converters, Signal Processing, 86(), 2006, 2803-2819.

[4] M. Schlegel, M.ech, Fractal system identification for robust control - the moment approach, Proceedings of the 5th International Carpathian Control Conference, 2004, 2004.

[5] N.M. Fonseca Ferreira, J.A. Tenreiro Machado, Fractional-order hybrid control of robotic manipulators, 11th International Conference on Advanced Robotics, 2003, 393-398.

[6] I. Podlubny, Fractional-order systems and PIλDμ controllers, IEEE Transactions on Automatic Control, 44(), 1999, 208-214.

[7] M.H. Rashid, Power Electronics: Circuits, Devices and Applications (Prentice-Hall, Second edition, USA, 1993) [8] Erickson, Robert W. Fundamentals of Power Electronics. Second Edition. Kluwer , 2004.

[9] C.A.Monje, Y.Q.Chen, B.M.Vinagre,D.Xue, V.Feliu, Fractional order systems and controls , ISSN 1430 – 9491, Springer London Dordrecht Heidelberg newyork, 2010 [10] F.L. Lewis, D.M. Dawson, C.T. Abdallah, Control of Robot Manipulators, New York, Macmillan, 1993.

Abstract: In this a genetic algorithm based approach to resolve the thermal unit commitment (UC). During this approach load demand, the most objective of getting a possible unit combination for every loading condition whereas subjected to a range of constraints. The model during this study contains four-generation units and also the 8-hour daily load demand. The results are compared between the dynamic programming (DP) and genetic algorithm the achieved results prove the effectiveness, and validity of the planned approach to unravel the large-scale UC. In the results indicating comparison of the cost solutions is using the genetic algorithm and the Dynamic Programming. The MATLAB Tool box is used to find the result.

Keywords: Genetic Algorithm, Unit Commitment, Mat lab toolbox.

[1]. R. K. Santhi, S. Subramanian, "Adaptive Binary PSO based Unit Commitment",International Journal of Computer Applications (0975 – 8887)Volume 15– No.4, February 2011.
[2]. C. Christopher Columbus, Sishaj P. "Simon, Hybrid Particle swarm approach for Securityconstrained unit commitment",International Conference on Computing, Electronics and Electrical Technologies [ICCEET],2012.
[3]. T.Logenthiran,DiptiSrinivasan,"LRGAfo$/hrolving Profit based GenerationScheduling Problem in Competitive Environment", 978-1-4244-7835-4/11/$26.00 ©2011 IEEE.
[4]. M.Sudhakaran,P.Ajay-D-Vimal Raj "Integrating genetic algorithms and tabu search for unit commitment problem ",IJEST Vol.2,no.1,2010,pp.57-69.
[5]. S. A. Kazarlis, A. G. Bakirtzis, and V. Petridis, "A genetic algorithmsolution to the unit commitment problem," IEEE Transaction onPower System, vol. 11, pp. 83–92, Feburary 1996.
[6]. K. S. Swarup and S. Yamashiro," Unit Commitment Solution MethodologyUsing Genetic Algorithm", IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 17, NO. 1, FEBRUARY 2002
[7]. JorgeValenzuela &AliceE.Smith "A seeded mimetic for larg unit commitment problem‟.
[8]. C.Christober Asir Rajan, M.R.Mohan,K.Manivannan ," Improved GeneticAlgorithm Solution to UnitCommitment Problem",0-7803-7525-4/02/$17.00 0 2002 IEEE.

Abstract: The research project for detecting magnetic fields in the femtotesla range at extremely low frequency noise is developed, including antenna, transformer and amplifier. Each component is described with relevant tradeoffs which allow a large variety of receivers to be easily designed for any magnetic field sensing in the very low-frequency noise range. This paper introduces a new ELF noise signal Inductor sensor design and find stability for pre amplifier & magnetic inductive. A system using an impedance antenna is developed further as an example that has been used extensively in measurement application in the frequency below 30Hz using MATLAB software tools.

Keywords: Extremely Low Frequency, amplifiers, loop antennas, magnetic field measurement, magnetometers

[1] Sarah K. Harriman,Student Member, IEEE, Evans W. Paschal, and Umran S. Inan,Fellow, IEEE "Magnetic Sensor Design for FemtoteslaLow-Frequency Signals" IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 48, NO. 1, JANUARY 2010
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[9] A. Karnik, "Performance of TCP congestion control with rate feedback: TCP/ABR and rate adaptive TCP/IP," M. Eng. thesis, Indian Institute of Science, Bangalore, India, Jan. 1999.
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Abstract: The dynamic behavior of two interacting system was studied by the introduction of a step change in inlet flow rate and with the development of the suitable mathematical model of this interacting system. This paper describes how the effect of the interaction of this interacting system is eliminated by the design of the suitable de-coupler for the system. This paper also includes the analysis of the interacting loops between the controlled variable that is liquid level and manipulated variable that is inlet flow rate by the help of relative gain array. The result exemplifies that the gain of each loop is reduced approximately half when the opposite loop is closed and the gain of other loop changes the sign when the opposite loop is closed. Thus the de-coupling method illustrate that it is one of the suitable method for the reduction of the interaction in the tanks system.

Keywords: interacting system, interacting loops, controlled variable, manipulated variable, relative gain array, de-coupler.

[1] TrielWeiler J.O.," Application of The Robust Performance Number for Quantification of the Operability of the Quadruple-Tank Process", Brazilian Journal of Chemical Engineering, Vol. 19, Page No. 195-206.

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Abstract: In this studying we present the designing and implementation of an electric chair for disabled persons, has the ability to rise on stairs with automatic controlling. The chair can be controlled to move in all directions and to raise the ramp and stairs with different degrees. The chair works with DC voltage source (Battery) can be recharged to work for long times. The design suggested has suitable size to be used in streets hospitals and home (width=88cm& length=125cm) also, can work with users weight reach to 90kg. It is also economically suitable comparing with that in markets as the cost of normal wheelchair walk only on the planes exceed 1300$, while our chair cost is about 600$ for one piece and this cost may be halved for a line of production. The stability problem solved in this studying using the hydraulic jacks with electrical controlling by using the angle measuring devices. The previous studying and designs where of complex design and with high cost while this design is specialized to be simple and of easy implementation .

Keywords: Design, Electrical Wheel Chair, Hydraulic Jack

[1] Batavia, M., PH. D (1998), " The wheel chair evaluation a practical guide", ISBN 0-7506-7037-1
[2] New Definition, http://www.assistive-technology.ca/newdef2.htm

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[6] J. M.Ford and S. J. Sheredos, "Ultrasonic head controller for powered wheelchairs". Journal Of Rehabilitation Research and Development, 1995, 32(3): pp. 280-284.

[7] ISO 7176-24:2004. Wheelchairs – Part 24: Requirements and test methods for user-operated stair-climbing devices. Geneva,International Organization for Standardization, 2004 (http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=31276, accessed 9 March 2008).

[8] B est KL et al. Wheelchair skills training for community-based manual wheelchair users: a randomized controlled trial. Archives of Physical Medicine and Rehabilitation, 2005, 86:2316–2323.

[9] ISO 7176-7:1998. Wheelchairs – Part 7: Measurement of seating and wheel dimensions. Geneva, International Organizationfor Standardization, 1998 (http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=13783,accessed 9 March 2008). [10] Krizack, M. The importance of user choice for cost-effective wheelchair provision in low-income countries. In: Proceedings, 12th World Congress of the International Society for Prosthetics and Orthotics, Vancouver, 29 July – 3 August 2007. Copenhagen, International Society for Prosthetics and Orthotics, 2007.