iosr-JEEE   Volume-7 ~ Issue-6

Abstract: Time Domain Reflectometry is a technique used for fault location and partial discharge analysis in underground electric distribution cables. The technique is based on the analysis of the propagation of short electric pulses. In underground cables, semiconductor layer properties and degradation cause perturbations in the signal wave shape. These perturbations complicate the interpretation of reflectograms and, as a consequence, fault location. This work presents a circuit model of distributed elements that includes the electrical resistance of the semiconductor layers. The results of computer simulations using the proposed model are compared with measurements in new and aged XLPE cables. This comparison shows that the proposed model can represent the phenomena satisfactorily.

Keywords : Underground cables, Simulation of Time Domain Reflectometry, Attenuation spectrum.

[1] V. DUBICKAS, H. EDIN and R. PAPAZYAN, "Cables Diagnostics with On-Voltage Time Domain Reflectometry," Royal Institute of Technology, 2006.
[2] D. k. CHENG, "Field and Wave Electromagnetics," Second Edition, Addison-Wesley Publishing Company, Boston, pp. 370 - 428, 1989.
[3] F. T. ULABY, E. MICHIELSSEN and U. RAVAIOLI, "Fundamentals of Applied Electromagnetics," Sixth Edition, Pearson, University of Michigan, pp. 67 - 131, 1994.
[4] P. WAGENAARS, P.A.A.F Wouters, P.C.J.M. Van Der Wielen and E.F. Steennis, "Estimation of Transmission Line Parameters for Single-core XLPE Cables," International Conference on CMD, pp. 1132 – 1135, Beijing, 2008.
[5] M. E. KOWALSKI, "A Simple and Efficient Computational Approach to Chafed Cable Time-Domain Reflectometry Signature Prediction," Stinger Ghaffarian Technologies (SGT), Inc. NASA Ames Research Center, 2008.
[6] V. DUBICKAS, "Development of On-line Diagnostic Methods for Medium Voltage XLPE Power Cables" Doctoral Thesis, Stockholm, Sweden 2009.
[7] R. PALUDO, "Refletometria no Domínio do Tempo: Análise das Camadas Semicondutoras de Cabos Isolados," Dissertation of Master, Curitiba 2009.
[8] R. PAPAZYAN and R. ERIKSSON, "Calibration for Time Domain Propagation Constant Measurements on Power Cables," IEEE Transactions on Instrumentation and Measurement, vol. 52, pp. 415 – 418, 2003.
[9] R. HEINRICH, S. BONISCH, D. POMMERENKE, R. JOBAVA and W. KALKNER, "Broadband Measurement of the Conductivity and the Permittivity of Semiconducting Materials in High Voltage XLPE Cables," Eighth International Conference on (IEE Conf. Publ. No. 473), pp. 212 – 217, 2000.
[10] G. MUGALA, R. ERIKSSON and P. Petersson, "Comparing Two Measurements Techniques for High Frequency Characterization of Power Cable Semi conducting and Insulating Materials," IEEE Trans. on Dielectrics and Electrical Insulation, vol. 13, pp. 712 – 716, 2006.

Abstract: In this study, a new boost converter with an active snubber cell is proposed. The active snubber cell provides main switch to turn on with zero voltage transition (ZVT) and to turn off with zero current transition (ZCT). The proposed converter incorporating this snubber cell can operate with soft switching at high frequencies. Also, in this converter all semiconductor devices operate with soft switching. There is no additional voltage stress across the main and auxiliary components. The converter has a simple structure, minimum number of components and ease of control as well. The Fuzzy Logic (FL) controller with two inputs maintains the load voltage by detecting the voltage variations through d-q transformation technique is connected in feedback of these converters. The presented theoretical analysis is measured in simulation results by 2.3kW and 100 kHz boost converter. Here output voltage up to 400v is given Also, the overall efficiency of the new converter has reached a value of 97.8% at nominal output power.

Keywords: Soft switching, zero current transition, zero voltage transition, DC-DC converter, Fuzzy Logic Controller

[1] G. Hua, C. S. Leu, Y. Jiang, and F. C. Lee, "Novel Zero-Voltage-Transition PWM Converters," IEEE Trans. on Power Electron., vol. 9, pp. 213-219, Mar. 1994.
[2] G. Hua, E. X. Yang, Y. Jiang, and F. C. Lee, "Novel Zero-Current-Transition PWM Converters," IEEE Trans. on Power Electron., vol. 9, pp. 601-606, Nov. 1994.
[3] H. Mao, F. C. Lee, X. Zhou, H. Dai, M. Cosan, and D. Boroyevich, "Improved Zero-Current-Transition Converters for High-Power Applications," IEEE Trans. on Ind. Applicat. , vol. 33, pp. 1220-1232, Sept./Oct. 1997.
[4] J. G. Cho, J. W. Baek, G. H. Rim and I. Kang, "Novel Zero-Voltage-Transition PWM Multiphase Converters," IEEE Trans. on Power Electron., vol. 13, pp. 152-159, Jan. 1998.
[5] C. J. Tseng and C. L. Chen, "Novel ZVT-PWM Converters with Active Snubbers," IEEE Trans. on Power Electron., vol. 13, pp. 861-869, Sept. 1998.
[6] V. Grigore and J. Kyyra, "A New Zero-Voltage-Transition PWM Buck Converter," in Proc. 9th Mediterranean Electrotechnical Conf. (MELECON′98) , Tel Aviv, Israel, vol. 2, 1998, pp. 1241-1245.
[7] J. M. P. Menegaz, M. A. Co., D. S. L. Simonetti, and L. F. Vieira, "Improving the operation of ZVT DC-DC Converters," in Proc. 30th Power Electron. Spec. Conf. (PESC′99) , Charleston, vol.1, 1999, pp. 293-297.
[8] K.M., Smith, and K.M., Smedley, "Properties and Synthesis of Passive Lossless Soft-Switching PWM Converters", IEEE Trans. on Power Electron., vol.14, pp. 890-899, Sept. 1999.
[9] C. M. de O. Stein, and H. L. Hey, "A True ZCZVT Commutation Cell for PWM Converters," IEEE Trans. on Power Electron., vol. 15, pp. 185-193, Jan. 2000.
[10] D. Y. Lee, B. K. Lee, S. B. Yoo, and D.S. Hyun, "An Improved Full-Bridge Zero-Voltage-Transition PWM DC/DC Converter with Zero-Voltage / Zero-Current Switching of the Auxiliary Switches," IEEE Trans. on Ind. Applicat., vol. 36, pp. 558-566, Mar. / Apr. 2000.

Abstract: This work concentrates on improving the system stability and increase the stability margin by well know FACT device STATCOM in nine bus system. The STATCOM generally used for power quality improvement as well as enhancement of stability. The enhancement of stability shows the capability of STATCOM during disturbance.

Keywords: Nine Bus system, Power Swing, Load Angle, STATCOM, PASCAD

[1] Beaulieu G., Bollen, M.H.J, Malgarotti S. and Ball R., Power quality indices and objectives. Ongoing activities in CIGRE WG36-07.Power Engineering Society Summer Meeting, 2002. IEEE, Volume:2, 21-25 July 2002, Pages: 789 – 794 vol.-2.

[2] M.H.J. Bollen, Understanding Power Quality Problems: Voltage Sags and Interruptions. New York, IEEE Press, 1999.

[3] M.H.J. Bollen, L.D.Zhang, Different methods for classification of three-phase unbalanced voltage dips due to faults. Electric Power Systems Research, Volume 66, Issue 1 2003, pages 59-69.

[4] P.M. Anderson and A.A. Fouad, "Power System Control and Stability", the IOWA state university press AMES IOWA USA, volume I, first edition 1977, chapter 2, page 37-38.

[5] Mehrdad Ahmad, Mostafa Alinezhad, "Comparison of SVC and STATCOM in Static Voltage Stability Margin Enhancement", Proceedings of World Academy of Science, Engineering and Technology, Vol. 38, Feb. 2009.

[6] Y.H. Song and A.T. Johns, "Flexible ac transmission systems (FACTS)", The Institute of Electrical Engineers, London, 1999.

[7] N.G. Hingorani and L. Gyugyi, "Understanding FACTS: concepts and technology of flexible ac transmission systems", IEEE Press,NY, 1999.

[8] K. R. Padiyar and A. L. Devi, "Control and simulation of static condenser," in Proc. 9th Annu. Applied Power Electronics Conf. Expo., Feb. 13-17, 1994.

[9] P. Rao, M.L. Crow and Z. Yang, "STATCOM Control for Power System Voltage Control Applications", IEEE Transactions on Power Delivery, Vol. 16, pp. 18-23, 2000.

[10] M.F. McGranaghan, D.R.Mueller, M.J.Samotyj, Voltage sags in industrial systems, IEEE Trans. Industry Applications, Vol.29, no.2, March/April 1993, pp.397 – 403.

Abstract: This paper presents an intelligent foraging behaviour based optimization approach i.e. artificial bee colony (ABC) algorithm for achieving the optimal power flow (OPF) problem solution incorporating the flexible alternating current transmission system (FACTS) device which is static synchronous series compensator (SSSC). The SSSC consists of a solid-state voltage source converter with gate turn off (GTO) device, a dc link capacitor, a magnetic circuit and a controller. The injected voltage is in quadrature with the line current and emulates an inductive or a capacitive reactance so as to influence the power flow in the transmission lines. The effectiveness of the approach has been tested on IEEE 14-bus system with and without SSSC. Results show that the ABC algorithm gives better solution to enhance the system performance with SSSC compared to without SSSC.

Keywords: Artificial Bee Colony Algorithm, Foraging Behaviour, Optimal Power Flow, Power Loss, SSSC.

[1]. A. Edris, R. Adapa, M.H. Baker, L. Bohmann, K. Clark, K. Habashi, L Gyugyi, J. Lemay, A.S. Mehraban, A.K. Myers, J. Reeve, F. Sener, D.R.Torgerson, R.R. Wood, Proposed Terms and Definitions for Flexible AC Transmission System (FACTS), IEEE Trans Power Delivery, Vol. 12, No.4, pp. 1848-1853, Oct. 1997.
[2]. N. G. Hingorani, L. Gyugyi, Understanding FACTS: Concepts and Technology of Flexible AC Transmission Systems, (IEEE Press, New-York, 2000).
[3]. R.M. Mathur and R.K. Varma, Thyristor-Based FACTS Controllers for Electrical Transmission Systems, (IEEE Press and Wiley Interscience, New York, USA, Feb. 2002).
[4]. M. A. Abido and Y. L. Abdel-Magid, Analysis and Design of Power System Stabilizers and FACTS Based Stabilizers Using Genetic Algorithms, 14th Power Systems Computation Conference PSCC2002, Session 14, Paper 4, Seville, Spain, June 24-28, 2002, CD-ROM.
[5]. L. Gyugyi, C.D. Schauder, K.K. Sen, Static Synchronous Series Compensator: A Solid-State Approach to the Series Compensation of Transmission Lines, IEEE Transactions on Power Delivery, Vol. 12, No. 1, Jan. 1997.
[6]. L. Gyugyi, C.D. Schauder, S.L. Williams, T.R. Rietman, D.R. Torgerson, A. Edris, The Unified Power Flow Controller: A New Approach to Power Transmission Control, IEEE Transactions on Power Delivery, Vol. 10, No. 2, Apr. 1995.
[7]. A.E. Eiben, J.E. Smith, Introduction to Evolutionary Computing, Springer, 2003.
[8]. R.C. Eberhart, Y. Shi, J. Kennedy, Swarm Intelligence, Morgan Kaufmann, 2001.

Abstract: This paper proposes an approach for the navigation of mobile robots namely Khepera 3 and iRobot Create in a designated environment. In this study, the navigation system of Khepera 3 includes the motion of the mobile robot at a particular angle to reach a particular goal and avoidance of the obstacle that may occur in its path. Obstacle avoidance is realized using Blending and Hard switching techniques respectively and the navigation system of iRobot Create includes its movement in a rectangular path. In controlling the navigation of the robots, Proportional-Integral-Derivative (PID) controller is used. The most suitable set of values of PID parameters implemented for safe and effective navigation of the robots have been presented. Computer simulation is done using MATLAB software.

Keywords: Navigation, Mobile robots, Obstacle avoidance, Blending, Hard switching, PID

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[3]. RAJKUMAR BANSAL, A.PATRA, VIJAYBHURIA, "Design of PID Controller for Plant Control and Comparison with Z-N PID Controller", International Journal of Emerging Technology and Advanced Engineering ,Volume 2, Issue 4, April 2012.
[4]. S. N. DEEPA, G. SUGUMARAN, "Design of PID Controller for Higher Order Continuous Systems using MPSO based Model Formulation Technique", International Journal of Electrical and Electronics Engineering, 5:4 2011.
[5]. CHIA-JU WU, TING-LI CHIEN, TSONG-LI LEE, and LI-CHUN LAI, "Navigation of a mobile robot in indoor environment", Journal of the Chinese Institute of Engineers, Vol. 28, No. 6, pp. 915-924 (2005).
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[9]. Sim.I.am: A Robot Simulator by Jean-Pierre de la Croix.

Abstract: This modulation method is based on selective virtual loop mapping, to achieve dynamic capacitor voltage balance without the help of an extra compensation signal. The concept of virtual sub module (VSM) is first established, and by changing the loop mapping relationships between the VSMs and the real sub modules, the voltages of the upper/lower arm's capacitors can be well balanced. This method does not requiring sorting voltages from highest to lowest, and just identifies the MIN and MAX capacitor voltage's index which makes it suitable for a modular multilevel converter with a large number of sub modules in one arm. Compared to carrier phase-shifted PWM (CPSPWM), this method is more easily to be realized in field-programmable gate array and is conducive to the control of circulating current. Its feasibility and validity have been verified by simulations.

Key terms: Dynamic voltage balance (DVB), modular multilevel converter (MMC), phase disposition pulse width modulation (PDPWM), Photovoltaic (PV),selective virtual loop mapping (SVLM).

[1] M. Guan and Z. Xu, "Modeling and control of a modular multilevel converter-based HVDC system under unbalanced grid conditions," IEEE Trans. Power Electron., vol. 27, no. 12, pp. 4858–4867, Dec. 2012.

[2] S. Jasekar and R. Gupta, "Solar photovoltaic power conversion using modular multilevel converter," in Proc. Student Conf. Eng. Syst., 2012,pp. 1–6. [

3] H.Akagi, "Classification, terminology, and application of the modular multilevel cascade converter (MMCC)," IEEE Trans. Power Electron.,vol. 26, no. 11, pp. 3119–130,Nov.2011. [

4] G. P. Adam, S. Finney, and B. Williams, "Analysis of modular multilevel converter capacitor voltage balancing based on phase voltage redundant states," IET Power Electron. J., vol. 5, no. 6, pp. 726–738, 2012.

[5] S. Rohner, S. Bernet, M. Hiller, and R. Sommer, "Modulation, loses, and semiconductor requirements of modular multilevel converters," IEEE Trans. Ind. Electron., vol. 57, no. 8, pp. 2633–2642, Aug. 2010.

[6] E. K. Amankwah, J. C. Clare, P. W. Wheeler, and A. J. Watson, "Multi carrier PWM of the modular multilevel VSC for medium voltage applications," in Proc. IEEE Appl. Power Electron. Conf. Expo., 2012, pp. 2398–2406.

[7] S.Sedghi, A. Dastfan, and A. Ahmadyfard, "A new multilevel carrier based pulse width modulation method for modular multilevel inverter," in Proc. IEEE Conf. Power Electron. ECCE Asia, Jeju, Korea, 2011,pp. 1432–1439.

[8] E. K. Amankwah, J. C. Clare, P. W. Wheeler, and A. J. Watson, "Multi carrier PWM of the modular multilevel VSC for medium voltage applications," in Proc. IEEE Appl. Power Electron. Conf. Expo., 2012, pp. 2398–2406.

[9] I. Abdalla, J.Corda, and L. Zhang, "Multilevel DC-link inverter and control algorithm to overcome the PV partial shading," IEEE Trans. Power Electron., vol. 28, no. 1, pp. 14–18, Jan. 2013.

[10] M. Hagiwara, R. Maeda, and H. Akagi, "Control and analysis of the modular multilevel cascade converter based on double-star chopper-cells (MMCC-DSCC)," IEEE Trans. Power Electron., vol. 26, no. 6, pp. 1649–1658, Jun. 2011

Abstract: This paper describes the expressions of Line Stability Factor (LQF) and Fast Voltage Stability Index (FVSI), which may be measured as sign of voltage collapse under inhibited condition of an interconnected power system. Artificial Neural Network Technique has been useful to recognize the voltage collapse condition. The Proposed method once the ANN model of the system is built-up, through on line checking of the load of the weak bus, the present method can immediately calculate the FVSI,and LQF without going through the complex classical calculations. The developed ANN technique has been experienced in IEEE 30 bus test system and ON-Line monitoring of 72-bus Indian southern power grid parameters is found to be more effective than the conventional method.

Key words: voltage stability, ANN, bus, LQP, FVSI.

[1] Wang, Meir Kiein, Solomon Yirga, PrabhaKundur," Dynamic reduction of large power system for stability studies", IEEE transaction on Power system, Vol-12, No-2, May 1997 Pages 889-895

[2] E vahedi, Y. Mansoor, Fuches, M. Lotero," Dynamic security constraint of the optimal power flow/Var planning", IEEE transaction on Power system, Vol-16, No-1, February 2001 Pages 38-43

[3] S.Arali, P. kundur, P. Haddink, D. Mathews," Small Signal stability of a large power system as affected by new generator addition", IEEE transaction on Power system, presented at power conference , China, 2002 pp 812-816 [4] A.M. Chibbo, M. R. Irving," Voltage Collapse Proximity indicator: behavior and implication", IEE Proc. May 1992

[5] M. Moghavvemi, F. M. Omar,"Technique for contingency monitoring and voltage collapse prediction", IEE proc. Generator, Transmission and Distribution, Vol-145, No-6 November 1998

[6] M. Moghavvemi, F. M. Omar," Real tine contingency evaluation and ranking Technique", IEE proc. Generator, Transmission and Distribution, Vol-145, No-5 September 1998

[7] Chakrabarty. S, Jeyasurya,B,"Online voltage stability monitoring using Artificial Neural Network", Power Engineering, 2004 LESCOPE-04 Large Engineering System Conference pp-71-75 [8] Jimenez, C.A. Castro, C.A," Voltage stability security margin assessment via Artificial Neural Network", Power Tech. June 2005 IEEE Russia, pp-27-30

[9] H. B. Wan, Y. H. Song, A. T. Johns: Artificial Neural Networks for power system Voltage Stability Assessment 1995 UPEC, Vol 1

[10] Suthar, B. Balasubramanian, R: Application of an ANN based voltage stability assessment tool to restructured power systems- Bulk Power System Dynamics and Control-VII. 19-24 Aug.2007 pp1-8

Abstract: In present scenario, the performance of power systems decreases with the size, the loading and the complexity of the system networks. This is related to problems with power oscillations, large power flow and voltage instability with inadequate control, so the power flow control plays a major role in power systems. In this paper SSSC series FACTS device are regulates system voltage by absorbing or generating reactive power and the control of active, reactive power flow and voltage well as damping power system oscillations in long transmission line. In this paper results of SSSC series FACT device compared with the STATCOM shunt FACT device and Simulation studies were carried out in the MATLAB simulation environment to observe the compensation achieved by the SSSC device. The system parameters such as voltage, current, active power and reactive power transmissions are observed when the SSSC, STATCOM device is connected to the power system. For the simulation purpose, the model of two-area four-machine 11-bus system with SSSC and STATCOM device is developed in MATLAB/SIMULINK using Simpower System (SPS) blockset.

Keywords: FACT Device, SSSC, STATCOM, Power Oscillation Damping (POD) controller, Test system model, MATLAB/SIMULINK, Modelling of SSSC, STATCOM

[1]. C.W.Taylor, "Power system voltage stability" McGraw-Hill, New York, (1994)
[2]. T.Van Custem, C.Vournas, (1998): Voltage stability of electric power system, Kluwer Academic publishers, Boston.
[3]. K.R Padiyar FACTS Controllers in Power Transmission and Distribution.
[4]. Edvina Uzunovic Claudio, A. Ca~nizares John Reeve, EMTP Studies of UPFC Power Oscillation Damping North American Power Symposium (NAPS), San Luis Obispo, California, October 1999.
[5]. F.D. Galiana, K. Almeida, M. Toussaint, J. Griffin, and D. Atanackovic: "Assessment and Control of the Impact of FACTS Devices on Power System Performance",IEEE Trans. Power Systems, Vol.11, No 4, Nov 1996.
[6]. L. Gyugyi, C. Schauder, K. Sen. Static synchronous series compensator: a solid-state approach to the series compensation of transmission lines. IEEE Transactions on Power Delivery, 1997,12(1): 406-41.
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Abstract: In modern days due to the ever increasing demand for power in expansion of transmission network, the transmission line are to be operated under loaded condition and there is a risk of power flow control and voltage instability. This paper proposes power flow control in a power system network by incorporating TCSC and SVC devices. The TCSC is a series compensated device to reduce the transmission line reactance in order to improve power flow through it, while the SVC is a shunt compensated device and they improve the voltage profile. This paper presents a systematic procedure for modeling and simulation using MATLAB/SIMULINK (Simpower System blockset). The optimal location of TCSC and SVC device are considered for power flow control and voltage stability limit. The proposed approach is carried out on two-area four-machine 11-bus test system model and the simulated result are presented to validate the proposed test case system. In this paper performance of TCSC and SVC device is analyzed and compare its simulated result for better power flow control in power system.

Keywords: FACTS devices (TCSC, SVC), Two-area 11 bus test system model, MATLAB/SIMULINK, Modelling of SVC and TCSC.

[1]. Hatziadoniu C.J. , Member, Funk A.K., "Development of a control scheme for a Series Connected Solid- State Synchronous Voltage Source" IEEE Transactions on Power Delivery.Vol. 11, No. 2, April, 1996.
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Abstract: Nanorobots are nanodevices that will be used for the purpose of maintaining and protecting the human body against pathogens. Nano is one billionth of one. Nanotechnology is the technology in which the operations are performed on nanometrics. It is the application of different technologies primarily interested in the reduction of size. The credential part of this paper gives the theoretical application of nanodevices in the treatment of AIDS. There is no technology for the treatment of AIDS. Some of the drugs of specific composition are given to the patients depending on the intensity of the disease.

[1]. Bodian D & Howe H A (1941). The rate of progression of virus in nerves
[2]. Molecular Biology of the cell by Bruce Alerts
[3]. K.Eric drexler , "Nanotechnology summary"
[4]. Arthur Guyton , "Textbook of medical physiology"

Abstract: The Interleaved Buck Converter (IBC) having low switching losses and improved step-down conversion ratio is suitable for the applications where the input voltage is high and the operating duty is below 50%. It is similar to the conventional IBC, but two active switches are connected in series and a coupling capacitor is employed in the power path. This IBC shows that since the voltage stress across all the active switches is half of the input voltage before turn-on or after turn-off when the operating duty is below 50%, the capacitive discharging and switching losses can be reduced considerably. This allows the IBC to have higher efficiency and operate with higher switching frequency. In addition, it has a higher step-down conversion ratio and a smaller output current ripple compared with a conventional IBC. Closed loop control using PI controller has been done to improve the system performances. By replacing the conventional voltage source by a renewable one will enhance its reliability and is more economical. So here the dynamics of a polymer electrolyte membrane fuel cell (PEM Fuel cell) is modelled, simulated and presented. MATLAB –SIMULINK is used for the modelling and simulation of the fuel cell stack. Design and analysis of the converter is done for a DC input of 200V and duty ratio D<0.5. The expected output DC voltage is 24V/10A. Simulation of both conventional and new IBC is done using MATLAB/SIMULINK and their outputs are compared.

Keywords : Buck converter, Fuel cell stack, Interleaved, Low switching loss.

[1] Il-Oun Lee, Student Member, IEEE, Shin-Young Cho, Student Member, IEEE, and Gun-Woo Moon, Member, IEEE, "Interleaved
Buck Converter Having Low Switching Losses and Improved Step-Down Conversion Ratio," IEEE Trans. on Power Electron., vol.
27, No.8, August 2012.
[2] R. L. Lin, C. C. Hsu, and S. K. Changchien,C. Y. Lin, M. Wu, "Interleaved four-phase buck-based current source with isolated energyrecovery
scheme for electrical discharge machine," IEEE Trans. Image Power Electron., vol. 24, no. 7, pp. 2249-2258, Jul. 2009
[3] C. Garcia, P. Zumel, A. D. Castro, and J. A. Cobos, "Automotive DC–DC bidirectional converter made with many interleaved buck
stages," IEEE Trans. Power Electron., vol.21, no.21, pp.578-586, May 2006.
[4] C. S.Moo, Y. J. Chen, H. L. Cheng, and Y. C. Hsieh, "Twin-buck converter with zero-voltage-transition," IEEE Trans. Ind. Electron.,
vol. 58, no. 6, pp. 2366–2371, Jun. 2011.
[5] J. P. Rodrigues, S. A. Mussa, M. L. Heldwein, and A. J. Perin, "Three level ZVS active clamping PWM for the DC–DC buck
converter," IEEE Trans. Power Electron., vol. 24, no. 10, pp. 2249–2258, Oct. 2009.
[6] Y. M. Chen, S. Y. Teseng, C. T. Tsai, and T. F. Wu, "Interleaved buck converters with a single-capacitor turn-off snubber," IEEE
Trans. Aerosp. Electronic Syst., vol. 40, no. 3, pp. 954–967, Jul. 2004.
[7] Akbari, M. H., "PEM Fuel Cell Systems for Electric Power Generation: An Overview," International Hydrogen Energy Congress and
Exhibition IHEC 2005, Istanbul, Turkey, 2005.
[8] Lemes, Z., Vath, A., Hartkopf, Th., Mancher, H.," Dynamic fuel cell models and their application in hardware in the loop simu lation,"
Journal of Power Sources, 154, (2006), 386-393.