iosr-JEEE   Volume-6 ~ Issue-5

Abstract: The Electrical power quality has become an important topic of discussion and research these days. As per IEEE 519 std. parameters of power quality measurement, are four in number, of which Total Harmonic Distortion is most widely used. This paper proposes the optimal planning of passive tuned harmonic filters for improvement of power quality in faulty conditions of electrical power system. The Total Harmonic Distortion analysis of power quality disturbances is carried out in the faulty conditions and in the presence of single tuned and double tuned harmonic filters. The four bus system having two load and two generator buses is modeled in MATLAB/Simulink environment. A fault is created near the load bus and power quality disturbances are detected near the generator bus and improved using single tuned and double tuned filters near the generator bus under study. The Matlab results show the performance of double tuned filter in improvement of power quality disturbances during faulty conditions.

Keywords – power quality disturbances, total harmonic distortion, power system fault, single tuned harmonic filter, double tuned harmonic filter.

[1] Manoj Gupta, Rajesh Kumar, and Ram Awtar Gupta, "Neural Network Based Indexing and Recognition of Power Quality Disturbances," TELKOMNIKA, Vol. 9, No.2, August 2011, pp. 227-236.

[2] R.Dugan, M. McGranaghan, and H. Wane Beaty, Electrical Power Systems Quality, McGraw-Hill, Ney York, 1996.

[3] Subhamita Roy, and Sudipta Nath, "Classification of power quality disturbances using features of signals," International Journal of Scientific and Research Publications, Vol. 2, Issue 11, November 2012, pp.01-09. [4] He H., Shen X, and Starzyk J.A., "Power quality disturbances analysis based on EDMRA method," Electrical Power and Energy System, Vol. 31, pp. 258-268.

[5] P.Daponte, M.di Penta, and G. Mercurio, Transientmeter: A distuributed measurement system for power quality monitoring," Proceeding 9th International Conference Harmonics and Quality of Power, 2000, Vo. 3, pp.1017-1022.

[6] M.Sushama, G.Tulasi Ram Das, and A.Jaya Laxmi, "Mitigation of voltage sags with dynamic voltage restorer using wavelets," Presented at the International Conference RACE 2007, March 22-24, 2007.

[7] Anoop Mathew, and Benisker Raja Singh D., "Image compression using lifting based DWT," International Journal of Computers Information Technology and Engineering, Vol. 3, January 2009, pp. 27-31.

[8] Inigo Monedero, Carlos Leon, Jorge Ropero, Antonio Garcia, Jose Manuel and Juan C. Montano, "Classification of Electrical Disturbances in Real Time Using Neural Networks," IEEE Transaction on Power Delivery, 2007, pp.1-9.

[9] D. Saxena, K.S. Verma and S.N. Singh, "Power quality event classification: an overview and key issues," International Journal of Engineering, Science and Technology, Vol. 2, No.3, 2010, pp. 186-199.

[10] S.Edwin Jose, and S.Titus, "Detection and classification of power quality using adaptive decomposition structure and neural network," European Journal of Scientific Research, Vol.89, No.3, October 2012, pp. 477-489.

Abstract: To meet the future energy requirement and to give quality and pollution free supply to growing and environment conscious population, the present world is giving special attention to natural, clean and renewable energy sources. Due to growing demand for electrical energy and environmental issues such as pollution and global warming effect, solar energy is considered among one of the best options for generating clean energy. In this paper a PI controller is used as an intelligent method for Maximum Power Point Tracking (MPPT) for a PV system. PI controller has been used for achieving the Maximum Power Point of a PV system. A boost converter is used to boost the voltage.

Keywords – PI controller, Maximum power point tracking, MPPT algorithm, Photovoltaic system

[1]. Kimiyoshi Kobayashi, Hirofumi Matsuo and Yutaka Sekine, "A novel optimum operating point tracker of the solar cell power supply system" ,IEEE Conference on Power Electronics,Volume 3, 20-25 June 2004.
[2]. M. G. Villalva, J. R. Gazoli, and E. R. Filho "Comprehensive Approach to Modeling and Simulation of Photovoltaic Arrays" IEEE Trans. Power Electr., vol. 24.
[3]. Y.Kuo-"Maximum Power Point Tracking controller for photovoltaic energy conversion system"-IEEE Trans Ind. Electron-Volume 48-2001.
[4]. Nicola Femia, Giovanni Petrone, Giovanni Spagnuolo, Massimo Vitelli "Optimization of Perturb and Observe Maximum Power Point Tracking Method" IEEE transactions on power electronics, vol. 20, no. 4, July 2005.
[5]. D. P. Hohm and M. E. Ropp, "Comparative Study of Maximum Power Point Tracking Algorithms", Progress in photovoltaics: research and applications Prog. Photovolt: res. Appl. 2003.
[6]. Xuejun Liu and Luiz A. C. Lopes , "An Improved Perturbation and Observation Maximum Power Point Tracking Algorithm for PV Arrays", 2004 35th Annual IEEE Power Electronics Specialists Conference.
[7]. Chung-Yuen Won, Duk-Heon Kim, Sei-Chan Kim "A New Maximum Power Point Tracker of Photovoltaic Arrays Using Fuzzy Controller", IEEE transaction 1994.
[8]. S. Armstrong and W.G Hurley "Investigating the Effectiveness of Maximum Power Point Tracking for a Solar System", IEEE Conference on Power Electronics, 2005.

Abstract: Path loss prediction models are essential tools in radio network planning for cellular transmission as they are used for received signal strength estimation, link budget design and analysis, cell size estimation, and interference optimization. This paper presents empirical path loss models developed for WCDMA microcells operating at 2100MHz on live radio Globacom Node Bs in the urban, suburban, and rural areas in Rivers state. The performance of COST 231 Hata model, Stanford University Interim, and Electronic Communication committee 33 were compared with measured field data. COST 231 Hata model gave a better prediction but with high RMSE and SD which are outside the acceptable value for a good radio signal propagation. COST 231 Hata model was for adjustment based on Linear Least Square Algorithm (LLSA). After adjustment and simulations, the adjusted COST 231 Hata model gave better predictions with minimum MSE and SD that are within the acceptable values. The adjusted COST 231 Hata can accurately be used for predicting the radio characteristic of Rivers State.

Keywords: Path loss prediction, cellular transmission, COST -231 Hata model, Mean Square Error, Standard Deviation, Linear Least Square Algorithm.

[1]. Rappaport, T.S, Wireless Communications, Second Edition, Pearson Publication, India, , pp 1392005,
[2]. Rakesh N. , Srivasta S.K, An Investigation on Propagation Path Loss in Urban Environments for Various Models at Transmitter Antenna Height of 5om and Receiver Antenna heights of 10m, 15m and 20m International journal of research and reviews in Computer science, vol 3 ,no 4 , 2012, pp 1761-1767, .
[3]. Bruno S.L Marcio R, Gervasio P, "Comparision Between Known Propagation Models Using Least Squares Tuning Algorithm on 5.8 GHz in Amazon Region Cities" Journal of Microwaves, Optoelectronics and Electromagnetic Applications, Vol.10, No,1, 2011,pp 106-113
[4]. Nwaogazie I. L. "Probability Statistics for Science and Engineering Parctice 2006, pp 114-120.
[5]. Nadir Z, Muhammed I. A "Pathloss Determination using Okumura –Hata Model And Cubic regression for Missing Data for Oman", Proceedings of the International Multi Conference of Engineers and Computer Scientists , IAEN-ICCSA 2010,Hong Kong 20 Vol II1, pp 804-807.
[6]. Luo Shuwan, Yang Geng, Propagation model tuning of TD-SCDMA, Guangdong Communication Technology, Guangdong Telecommunication Press, pp 37-41,2002
[7]. M.Yang, W.Shi, A Linear least Square Method of propagation model tuning for 3G Radio Network Planning, Fourth International Conference on National Computation ICNC,Jianan,pp150-154

Abstract: An electricity audit of a building is the process whereby an energy manager survey and analyzes how energy is used in the building with the main objective of identifying opportunities for reducing the amount of energy used and ensuring that available energy is used efficiently. This study reports the outcome of an electricity audit on a typical residential building in a major location of Ibadan metropolis. The audited building is a four – flat apartment where all the customers in the building have different tariff plans. Two of the customers labeled Customer A and B are metered, while the other two Customers labeled C and D are not metered. The result of the audit showed that the metered customers were paying the actual estimated electricity bills, while the non – metered customers were over billed by over 30 and 80% respectively. The study concluded by recommending the metering of all residential apartments and the use of pre – paid meters as it not only stimulate demand but also is more effective in the electricity billing process

Key Words: Electricity Audit, Residential Building, Ibadan

[1]. Electric Power Research Institute (1993) - Reduction cost by understanding your bill.
[2]. Ezeruigbo E. N (2001) - AT&C Loss reduction India Experience
[3]. Osideide, A. A. (2011) - Strategic electricity marketing Activities in distribution companies of Nigeria
[4]. PHCN(2011) - Commercial instruction manuals
[5]. Taylor Francis Group LLC, (2006) - Handbook of energy efficiency and renewable energy

Abstract: In this paper shows the simulation results about the reduction of the current peak of PFC converter connected to voltage source converter excited induction generator for wind power generation. This is one of the investigations of new combination of the induction generator for wind power and the power electronic equipments. Induction generator is popularly used for the wind power generation. The disadvantage of it is impossible to generate power at the lower rotor speed than the synchronous speed. To compensate this disadvantage, expensive synchronous generator with the permanent magnets sometimes used. In proposed scheme, the diode rectifier is used to convert the real power from the induction generator to the intermediate dc voltage, while the reactive power necessary to excite the induction generator only is supplied from the voltage source converter (VSC). This means that the rating of the expensive VSC is minimized and total cost of the wind power generation system is decreased compared to the system with synchronous generator. The MATLAB/Simulink is made for the controlling of the voltage source converter and boost dc/dc chopper. By using the duty ratio of the chopper can be controlled and for the generation of pulse width modulated (PWM) firing pulses for the voltage source converter. Index Terms: WECS, Total harmonics distortion, , FFT, SCIG,VSC

[1] Noriyuki Kimura , Tomoyuki Hamada, Makoto Sonoda , Toshimitsu Morizane Katsunori Taniguchi and Yasuyuki Nishida, " Suppression of current peak of PFC converter connected to induction generator for wind power generation excited by voltage sources converter". IEEE 6th International Conference on power electronics and motion control, Page(s): 2269-2274, 17-20 May 2009.

[2] Bhim Singh, Shailendra Sharma ," Stand-Alone Wind Energy Conversion System withan Asynchronous Generator", Journal of Power Electronics, Vol. 10, No. 5,pp.538~547, September 2010

[3] Noriyuki Kimura, Toshimitsu Morizane, Katsunori Taniguchi, Tomoyuki Hamada, "Control of PFC Converter with Inverter Excited Induction Generator for Advanced Wind Power Generation System ", Proceedings of PESC'08 "The 39th IEEE Power Electronics Specialists Conference", June15-19, 2008

[4] Noriyuki Kimura, Toshimitsu Morizane, Katsunori Taniguchi, Tomoyuki Hamada, "Wind Power Generation System with Induction Machine and Diode Rectifier ", EPE 2007, 12th European Conference on Power Electronics and Applications, No.0436, (2007-9)

[5] L. Leclercq, et.al, "Grid Connected or Islanded Operation of Variable Speed Wind Generators Associated with Flywheel Energy Storage Systems", EPE-PEMC-2004 Riga, Latvia. (European Association of Power Electronics and Applications - Power Electronics and Motion Control conference).

[6] Noriyuki Kimura, Toshimitsu Morizane, Katsunori Taniguchi, Tomoyuki Hamada, " Control of PFC Converter with Inverter Excited Induction Generator for Advanced Wind Power Generation System ", Proceedings of PESC'08 "The 39th IEEE Power Electronics Specialists Conference", June15-19, 2008
[7] Hirachi, K. ; Res. & Dev. Div., Yuasa Corp., Osaka, Japan ; Nishimura, K. ; Baba, N. ; Gamage, L. ," Engine-driven generator interactive three-phase switched-mode PFC converter and its performance evaluations ",Industrial Electronics, 1997. ISIE '97., Proceedings of the IEEE International Symposium onpp 612~618 (Volume:2 )
[8] Hansen, L.H. Madsen, P.H.; Blaabjerg, F.; Christensen, H.C.; Lindhard, U.; Eskildsen, K. "Generators and power electronics technology for wind turbines" IECON 2001, vol.3, pp: 2000 -2005

[9] Nicolás, C.V, Lafoz, M. And Iglesias, J. "Guidelines for the Design and Control of Electrical Generator Systems for new Grid connected Wind Turbine Generator." IECON 2002.

[10] Weigand, C.H., Lauw, H.K. and Marckx, D.A. "Variable-Speed Generation Subsystem Using the Doubly Fed Generator." NREL, April 1999. .

Abstract: In recent years, many new materials have been investigated in order to meet the need of high energy density for thin film batteries. Silicon based anode materials are attracting wide attention because of the highest theoretical capacity. By using DC magnetron sputtering method Aluminium film was deposited on ceramic substrate which acts as a current collector. Nanocrystalline film of Aluminium-Silicon-Chromium(Al-Si-Cr) alloy was deposited on aluminum film by using same sputtering method. High purity Aluminium-Silicon-Chromium metal alloy sputtering target was used for the film deposition. For comparison of anode cycling performance, pure Silicon thin films were also prepared by using same sputtering method. Al-Si-Cr films were analysed by XRD, EDAX, AFM and SEM . The crystallite size was determined by FWHM of XRD peaks. Particle size and microstructure of the film have been studied by SEM and AFM. The Al-Si-Cr thin film composition was analysed by EDAX. Composition ratio between Aluminium Silicon and Chromium obtained by EDAX is 2:3:5. Electrochemical properties of the films were analyzed by preparing lithium battery cell. Lithium insertion and excretion was performed by Cyclic Voltametry. Effect of cycling on structure stability of Al-Si-Cr anode film was studied by SEM analysis.

Keywords: anode , Al-Si-Cr alloy,thinfilm ,battery, lithium ,magnetron sputtering ,

[1] S.D. Jones and J.R. Akridge, Solid State Ionics, 53, 1992,628.
[2] J.B. Bates, N.J. Dudney, G.R. Gruzalski, R.A. Zuhr, A.Choudunry, C.F. Luck and J.D. Robertson, J. Power Sources, 43, 1999,103 ,
[3] J.B. Bates, N.J. Dudney, B.J. Neudecker, F.X. hart, H.P.Jun and S.A. Hackney, J. Electrochem. Soc., 147, 2000 ,59 .
[4] B.J. Neudecker, R.A. Zuhr and J.B. Bates, J. PowerSources, 81, 1999 ,27
[5] J.B. Bates, N.J. Dudney, B. Neudecker, A. Ueda and C.D. Evans, Solid State Ionics,135, 2000,33
[6] J. Lee, H.Y. Lee, S.H. Jeong, H.K. Baik and S.M. Lee, J.Power Sources, 11, 2002,345.
[7] Y.L. Kim, S.J. Lee, H.K. Baik and S.M. Lee, J. PowerSources, 119, 2003 ,106 .
[8] S.J. Lee, H.Y. Lee, H.K. Baik and S.M. Lee, J. PowerSources, 119, 2003,113).
[9] S. Ohara, J. Suzuki, K. Sekine and T. Takamura, J. PowerSources, 119, 2003 ,591
[10] J.P. Maranchi, A.F. Hepp and P.N. Kumta, Electrochem.Solid-State Lett., 6, 2003, A198.

Abstract: A new three-phase four-wire DSTATCOM (distribution static compensator) based on three-leg VSC (voltage source converter) and a star/delta transformer is proposed for power quality improvement. The star/delta transformer connection mitigates the neutral current and the 3-leg VSC compensates harmonic current, reactive power and balances the load. Three single phase transformers are connected as star/delta transformer for interfacing to a three phase four-wire power distribution system and the required rating of the VSC is reduced. However, a 4-leg VSC (voltage source converter) based DSTATCOM (Distribution Static Compensator) is used for the load compensation and neutral current compensation in 3-phase 4-wire distribution system. For extracting the reference source currents, Instantaneous Symmetrical Component Theory (ISCT) based control algorithm is modified for voltage regulation and used with indirect current control technique for controlling the DSTATCOM currents. The DSTATCOM is controlled for power factor correction and voltage regulation at PCC (point of common coupling). Simulations are performed for various load conditions such as a reactive linear load, an unbalanced load and a non-linear load in Power Factor Correction (PFC) mode and in Zero Voltage Regulation (ZVR) mode in MATLAB environment using SIMULINK and Sim Power System (SPS) toolbox.

Keywords - DSTATCOM, VSC, ISCT, ZVR.

[1] A. Ghosh and G. Ledwich, Power Quality Enhancement Using Custom Power Devices. London, U.K.: Kluwer, 2002.
[2] R. C. Dugan, M. F. McGranaghan, and H. W. Beaty, Electric Power Systems Quality, 2nd ed. New York: McGraw-Hill, 2006.
[3] H. Akagi, E. H. Watanabe, and M. Aredes, Instantaneous Power Theory and Applications to Power Conditioning Hoboken, NJ: Wiley, 2007.
[4] A. Moreno-Munoz, Power Quality: Mitigation Technologies in a Distributed Environment. London, U.K.: Springer-Verlag, 2007.
[5] E. F. Fuchs and M. A. S. Mausoum, Power Quality in Power Systems and Electrical Machines. London, U.K.: Elsevier, 2008.
[6] IEEE Recommended Practices and Requirements for Harmonics Control in Electric Power Systems, IEEE Standard 519, 1992.
[7] L. H. Beverly, R. D. Hance, A. L. Kristalinski, and A. T. Visser, "Method and apparatus for reducing the harmonic currents in alternating current distribution networks," U.S. Patent 5 576 942, Nov. 19, 1996.
[8] H.-L. Jou, J.-C. Wu, K.-D. Wu, W.-J. Chiang, and Y.-H. Chen, "Analysis of zig-zag transformer applying in the three-phase four-wire distribution power system," IEEE Trans. Power Del., vol. 20, no. 2, pp. 1168–1173, Apr. 2005.
[9] H.-L. Jou, K.-D. Wu, J.-C. Wu, and W.-J. Chiang, "A three-phase four-wire power filter comprising a three-phase three-wire active filter and a zig-zag transformer," IEEE Trans. Power Electron., vol. 23, no. 1, pp. 252–259, Jan. 2008.
[10] H. L. Jou, K. D. Wu, J. C. Wu, C. H. Li, and M. S. Huang, "Novel power converter topology for three-phase four-wire hybrid power filter," IET Power Electron., vol. 1, no. 1, pp. 164–173, 2008.

Abstract: Classification of Partial discharge (PD) patterns is an important tool to determine the sources of the PD. Also the features that specify of the patterns can be used monitor the condition of the electrical insulation. A PD patterns classification approach of artificial partial discharge sources by using neural networks is proposed in this paper. The classification process was based on features generated from three-dimension PD patterns. These features were obtained with the aid of fractal geometry. The box counting technique is used to generate the fractal features (fractal dimension and lacunarity). Each PD pattern has a unique Fractal dimension and several values for lacunarity depends upon the size of the box. Therefore each PD pattern is characterized by two features but with several quantities. The number of input features and their contents of information determine the performance of neural networks based classification system. In this paper an attempt to improve the performance of PD classification systems by minimizing the number of the input features was introduced. This was done by investigating the ability the different lacunarity values to classify different PD sources. A wide range of box size was investigated. The obtained results show that the lacunarity values generated from a very narrow range of box sizes has the maximum ability for PD classification.

Keywords: Partial Discharge Pattern, Fractal Dimension, Lacunarity

[1] Ganesh Rao & Shailja Shukla" Pattern Classification Of Partial Discharge In L.V. Winding Of 1-Transformer Using PCA" International Journal of Information Technology and Knowledge Management January-June 2011, Volume 4, No. 1, pp. 1-5.

[2] E. Kuffel, W.S. Zaengl and J. Kuffel, "High Voltage Engineering Fundamentals". 2nd, Butterworth – Heinemann, 2000

[3] K. Zalis, "Applications of expert systems in evaluation of data from partial discharge diagnostic measurement," in Proc. 7th International Conf. Properties and Applications of Dielectric Materials, pp. 331-334, June 2003.

[4] Muhamad Mansor, Prodipto Sankar Ghosh & Ahmad Basri Abdul Ghani ," PD Patterns Recognition In XLPE Cable Under Various Thermal Conditions Using Statistical Technique ", IJRRAS 5 (2) ,November, (2010),p.p. 171-181.

[5] S. Boonpoke and B. Marungsri" Pattern Recognition of Partial Discharge by Using Simplified Fuzzy ARTMAP", World Academy of Science, Engineering and Technology China, pp 212-219, September 2010.

[6] Hung-Cheng Chen, Feng-Chang Gu, Chun-Yao Lee "A New Method Based on Extension Theory for Partial Discharge Pattern Recognition", Wseas Transactions on Systwms, Issue 12, Volume 7, pp.1402-1411, December 2008.

[7] PO-Hung Cheni, Hung-Cheng Chen, An Liu, Li-ming Chen "Pattern Recognition For Partial Discharge Diagnosis Of Power Transformer", Proceedings of the Ninth International Conference on Machine Learning and Cybernetics, Qingdao, Vol. 4493, pp. 2996-3001, July 2010.

[8] Hung-Cheng Chen, PO-Hung Chen, and Meng-Hui Wang " Partial Discharge Classification Using Neural Networks and Statistical Parameters", International Conference on Instrumentation, Measurement, Circuits & Systems, April 15-17, 2007,p.p 84-88.

[9] Karthikeyan, B., Gopal, S., & Venkatesh, S. (2006). "ART 2 – An unsupervised neural network for PD pattern recognition and classification", International Journal on Expert Systems with Applications, 31, 345–350.

[10] S. S. Chen, J. M. Keller, R. M. Crownover, "On the Calculation of Fractal Features from Images," IEEE Transaction on Pattern Analysis and Machine Intelligence, Vol. 15, October 1983, pp. 1087-1090.

Abstract: Despite the advantages of variable Speed pumped storage power plant (PSP) included, as following statements: increasment of optimum efficiency in production mode and consumption mode, high speed for grid's requirements response in critical moments (such as: disturbances, black out,…); it's necessary, to achieve these benefits easily by energy storage practices. Now Doubly Fed Asynchronous Machine (DFAM) technology by means of modern equipment (MLVSC, Cycloconvertor) and employment of them is considered to achieve mentioned purposes, synchronous machines instead in PSP units. In this paper, technical comparison between the several kinds of PSP's drives methods is presented; also a PSP's unit is modeled (as electric, hydraulic, mechanic& control system) and simulated by Direct Torque Control (DTC) technique and TwoLevelVSC equipment, as novelty.Application of TwoLevelVSC and DTC method togethercaused to increase very high dynamic response of PSP in uninterrupted operationthe whole of times.The results of paper in Generation mode, express to increase efficiency in one unit of 4×250MW PSP that justifiesvariable SpeedPSP application. The simulations performed by Matlab software.

Keywords: Variable Speed Pumped Storage Power Plant (PSP), Direct Torque Control (DTC), Doubly Fed Asynchronous Machine (DAFM),Two-Level Voltage Source Converter (VSC).

[1] J. Janing, A. Schwery, Next generation variable speed pumped-storage power station, IEEE Trans. PowerElectron, vol. 25,Feb 2010, pp. 442-452.
[2] Mohammed O. A., Liu Z. and Liu S., Stator power factor adjustable direct torque control of doubly-fed induction machines, IEEE International Conf. on Electric Machines and Drives, 2005, pp. 572–578.
[3] M. Aghasi, D. A. Khaburi, V. Faraji and H. Behnia,A Comparative Study on Predictive and ISVM Direct Torque Control Methods for a Doubly Fed Induction achine Fed by an Indirect Matrix Converter,Iranian Journal of Electrical & Electronic Engineering, Vol. 8, No. 2, June 2012.
[4] G. Magsaysay, T. schuette, R.J. Fostnk, Use of a Static Frequency converter for Rapid load Response in pumped - Storage plants, IEEE Transactions on EnerggConvertion, Vol.10, NO.4, December 1995, pp 694-699.
[5] S. M. Hosseni, S. A. Banihashem, Y. Darbandy, Use of Static Frequency Converter Technology in Pumped Storage Power Plant for Dynamic Reaction of Load Response (SFC), International Power System Conference (PSC 2006),Tehran, Iran (Persian).
[6] H. Arabian, H. Abadi, The reliability model of Wind Turbine with Brushless Doubly Fed Induction Generator,Thesis Doctoral on Power-electrical Engineering, Sharif University of Industrial, Tehran, Iran, 2009.
[7] S. M. Hosseni, M. R. Semsar, MagidAgasi, Technical&Economical Comparison between Control methods of Pumped storage Power Plants, International Conference on Dams & Hydropower (ICDH2012), Tehran, Iran.

Abstract: The main subject of the essay is study of ferroresonance in the voltage transformers at 400kV GIS substation. Ferroresonance has destructive effects such as, undulations of high voltages, warming of transformers, increasing of heat, temperature increasing and damaging voltage transformers, high noise due to evolution due to magnet and bad working of protective instruments. So we have to apply limitations on system parameters to avoid such an undesirable phenomenon like this. In this paper ferroresonance phenomenon on VTs of real GIS substation (karon 4 power plant had been studied. With regarding high risk of ferroresonance due to studied substation conditions, damping circuit (FDSD, ZD) had been designed with help of EMTP-RV and the results are presented in two conditions of being without damping and by using of damping in the circuit. The results show damping circuit is successful in obviation of these dangerous oscillations.

Keywords: Gas Insulated Substation (GIS), Voltage Transformers (VT), Ferroresonance, FDSD, ZD

[1] K. H. Tseng P.-Y. Cheng Department of Electrical Engineering, National Taipei University of Technology, No. 1, Sec. 3, Chung-
Hsiao E. Rd.,"Mitigating 161 kV electromagnetic potential transformers' ferroresonance with damping reactors in gas-insulated
switchgear"Published in IET Generation, Transmission & Distribution Received on 27th June 2010.
[2] Hyundai Reports "ferroresonance of VT " Hyundai Heavy Industries Co., LTD ,Electro Electric System Div./Electro -Mechanical
Research Institute 2011.
[3] David A. N. Jacobson, Member IEEE "Examples of Ferroresonance in a High Voltage Power System "2003 IEEE.
[4] Q ing Liu, Yufeng Zhang "Influence of Switching Conditions on Very Fast Transient Over -voltage in500kV Gas Insulated Substation"
Department of Electrical and Control Engineering Of Xi'an University of Science and Technology, Xi'an, 710054, China.
[5] SaeedShahabi, ElectricalEngineering Department, Iran University of Science & Technology, Rasul EsmaeilniaShirvani, Islamic Azad
University of Saveh, Mohammad Purrezagholi, Babol University of Technology "Mitigating Ferroresonance in Coupling Capacitor
Voltage Transformers with Ferroresonance Suppressing Circuits"©2009 IEEE.
[6] H. Mohseni, J. Jadidian, A. A. Shayegani-Akmal, E. Hashemi, A. Naieny and E. Agheb "In-situ Insulation Test of 400 kV GIS", IEEE
Transactions on Dielectrics and ElectricalInsulation Vol. 15, No. 5; October 2008 .
[7] D. Shoup, Member, IEEE, J. Paserba, Fellow, IEEE, D. Sullivan, Member, IEEE P. Bolin, Senior Member, IEEE, R. Whiteside, Senior
Member, IEEE "ferroresonance Analysis of 500 kv Gas-Insulated substation "2011 IEEE.
[8] A. Abbasi, and A. Seifi, "Fast and perfect damping circuit for ferroresonance phenomena in coupling capacitor voltage transformers,"
Journal of Electric Power Components and Systems, Apr. 2009.
[9] W. Piasecki, M. Stosur, M. Florkowski, M. Fulczyk, B. Lewandowski"Mitigating Ferroresonance in HV inductive", Presented at the
International Conference on Power System Transients (IPST'09) in Kyoto, Japan on June 3 -6, 2009.

Abstract: Capacitive voltage and current induction is one of the most significant phenomenon's in high voltage GIS substation that the presence of it can impose problems to the substation operation. This paper has simulated the various equipment of 420 kV of Karoon4 substations such as powerhouses, input and output lines, bus-bar and bus-duct. EMTP-RV software has been used to simulate the equipment. Then with the considering of single-phase and three-phase faults on the line in critical conditions, capacitive voltage and current induction to the power network by parallel capacitor with circuit breaker is surveyed. The results are the maximum values of probable induced current and voltage that can be occurred. The breaker equipment of must be able to interrupt this value of current. Keywords: Gas insulated substation (GIS), induct current, induced voltage

[1] Kumar, V.V., J.M. Thomas, M.S. Naidu, 2001 Influence of switching conditions on the VFTO magnitudes in a GIS, IEEE Trans, Power Delivery, 16, 539-544.
[2] Kondalu, M., Gillella Sreekanth Reddy, Dr.P.S.Subramanyam, 2001. Estimation of Transient over Voltages in Gas Insulated busduct from 220kv Gas Insulated Substation, International Journal Computer Applications (0975 – 8887).
[3] Liu, Qing, Yufeng Zhang, 2008. Influence of Switching Conditions on Very Fast Transient Over-voltage in500kV Gas Insulated Substation, Department of Electrical and Control Engineering of Xi'an University of Science and Technology, Xian, China, 710054.
[4] Switching Capability of 420 kV Disconnecting Switch, Hyundai Heavy Industrial Co. LTD, Electro Electri System Div. /Electro- Mechanical Research Institute, , November 2011.
[5] Tavakoli, A., A. Gholami, A. Parizad, H.M. Soheilipour, H. Nouri2009. Effective Factors on the Very Fast Transient Currents and Voltage in the GIS, T & D, Asia and Pacific, October 26-30.
[6] Thompson, 1999. Inductance Calculation Teqnique-Approximations and Handbook Methods, Power Control and Intelligent Motion, 25: 40_45.

Abstract: The design, analysis and implementation of a robot arm system, which is expressed towards its performance with an analytical model by using LabVIEW and embedded system tools was presented in this article. Mathematical modeling of kinematics plays an essential role in design and implementation of a robot arm control. The projected work was focused to control the end effector of the robot arm to achieve any accessible point in an amorphous region using LabVIEW, ARM (Advanced RISC (Reduced Instruction Set Computing) Machine) microcontroller and Dexter ER2 robotic arm. LabVIEW uses analytical method to design the inverse kinematic model of the robot arm. The inverse kinematic model and robot arm control was implemented using LabVIEW and ARM microcontroller. LabVIEW uses the parallel communication to send the joint angles of the robot arm to the ARM. ARM microcontroller uses five PWM (Pulse Width Modulation) signals in order to control the robot arm, which was geared up with servo motors. Robot arm was controlled manually through the LabVIEW GUI (Graphical User Interface) controls. The present paper discussed about the mechanical configuration, analytical modeling, software and hardware of the above said work.

Keywords: Robot Arm, LabVIEW, ARM microcontroller, Parallel Communication, Inverse Kinematics.

[1] Mark S., Seth H. and Vidyasagar M., Robot modeling and control (John Wiley & Sons, 2006).
[2] http://zone.ni.com/reference/en-XX/help/372983C-01/lvrobogsm/robo_arm_definition/
[3] Jamshed Iqbal, Raza ul Islam, and Hamza Khan, Modeling and Analysis of a 6 DOF Robotic Arm Manipulator, Canadian Journal on
Electrical and Electronics Engineering , 3 (6) , July 2012, 300–306.
[4] Tsai L.W., Robot Analysis: The mechanics of serial and parallel manipulators, (John Wiley & Sons, 1999).
[5] Sanjay Lakshminarayan, Shweta Patil, Position Control of Pick and Place Robotic Arm, International Conference On Engineering
Innovation and Technology, ISBN : 978-93-81693-77-3, Nagpur, 1st, July, 2012.
[6] Ashraf Elfasakhany, Eduardo Yanez, Karen Baylon, Ricardo Salgado, Design and Development of a Competitive Low-Cost Robot
Arm with Four Degrees of Freedom, Modern Mechanical Engineering, 1, November 2011, 47-55.
[7] Adrian Olaru and Serban Olaru, Optimization of the robots inverse kinematics results by using the Neural Network and LabVIEW
simulation, 2011 International Conference on Future Information Technology, IPCSIT vol.13 2011, IACSIT Press, Singapore, 40-45.
[8] Serdar Kucuk and Zafer Bingul, Industrial Robotics: Theory, Modelling and Control, (ISBN 3-86611- 285-8, Germany, December
2006, Edited by: Sam Cubero).
[9] R. S. Hartenberg and J. Denavit, A kinematic notation for lower pair mechanisms based on matrices, Journal of Applied Mechanics,
vol. 77, pp. 215–221, June 1955.
[10] Paul, Richard (1981). Robot manipulators: mathematics, programming, and control: the computer control of robot
manipulators.(Cambridge, MA: MIT Press. ISBN 978-0-262-16082-7).