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International Journal of Advanced Technology in Engineering and Volume No.02, Issue No. 06, June 2014

www.ijates.com ISSN (online): 2348 – 7550

HIGH-LOW VOLTAGE RISK PREVENTION OF UAV ELECTRICAL GENERATION SYSTEM BASED BUCKBOOST INVERTER 1

Ahmed K. Abbas, 2Abadal-Salam T. Hussain, 3 F. Malek,Waleed A. Oraibi,4Qais H. Jeflawi, 5Israa A. Dahham 1,2,3,4,5

University Malaysia Perlis (UniMAP), School of Electrical System Engineering Center of Excellence for Renewable Energy (CERE), Campus Unimap Pauh Putra, 02600 Arau, Perlis, MALAYSIA.

ABSTRACT The converters needs is to obtain constant and stable output voltage from the variable input voltage as (renewable energy resources), when it is on the increases up or it decreases. In this paper, mode controlsare introduced together with true time of Buck- Boost converter. So it'sdecrease in the ripple content, cost, size and increase the efficiency of output voltage. In theusual control methods, immediate transference from Buck to Boost process, produceunfavorable ripple voltage in the output voltage. Subsequently, design Buck - boost converter with amended in transit rejoinder extremely reduce the ripple, which is show the output. However the process of eliminate the lineal Buck-Boost mode process, introduces is consist from intermediate combination mode by consist from several of Buck modesprocess. At the results in reduction in ripple signification and improved the efficiency of the output voltage.

Keywords: Constant Output Voltage, True That Time of (Buck-Boost) Converter, Regulation, Efficiency and Transients.

I. INTRODUCTION The multilevel converter has been discovered as a new generations of power converterthrough the last a few years. Several number of multilevel converters modulation technologies and the topologyhas been applied tothe elevation power. The major goals for using the multilevel converterleftover on their capability to get a high efficient, furthermore lineaments, that is need adependable of distribution the voltage between the number of related semiconductor switch. In addition, there is a possibility to development ofthe synthesis harmonicssignification, yield bring down the level of conducted and irradiate electromagnetic interferences. Theadvantage hasengage anenormous benefit in industry. The basic theory as regards current or multilevelvoltage converters [1]. Several of apologies based in the organization of everycommutation or converters. The Current multilevel converter consists in substitution method to associate commutation [2]. This is a new techniques that have been applied of AC-DC (rectifiers) converter, DC-AC (inverters) and DC-DC (choppers).

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The majorproblem of convert the voltage from DC-DC that is toapply in the high power. The MOSFET is limitation of the high voltage, the non-insulated convertereach in a restrict area, hardly dependent on the high voltage converters, or in need of associationor have to be more expensivefor switches tolet the desire conversion. One solutions is using transformers, but in this elements introducehave many disadvantages at the system, will be at low efficient, and also can avoid if the insulation is not needful. In the order to produce possible the operation of those converter in a high voltage, however keeping the high frequency, offered a three-level commutations, andthat applied forthe Buck, Boost and (Buck- Boost) converter. The commutation provide the divide of the highestvoltage outputand input to the Buck and Boost, on series or sum the input and the output of (Buck- Boost).

II. RELATED WORK The idea of DC–DC converters came to existence last few years. The passive components (inductor and capacitor) form an integral part of most of the architectures of dc converters as seen in figure 1&2. As inductor occupies around 30% area of the chip, technology of micro-fabricating the inductor on chip was developed. Later inductor-less dc converters. Switched capacitor ofdc converters were designed for low power application [3]. A new architecture of down converter consisting of reference voltage generator, voltage follower and pass device was designed for low power digital circuits [4, 5]. Most of the converters were designed with length of 0.18 um. However, with technology scaling, there was a huge impetus on reducing the converter size. In recent development, the challenges faced while designing converters with length of 90 nm were described.

III. MATHEMATICAL MODELING

Subinterval 1

Subinterval 2

Figure 1. Non-inverting buck-boost converter Page | 53


Sub-inverter 1


Sub-inverter

Inverting Buck- Boost 2

Figure 2. Reversal of output voltage polarity One terminal of inductor usuallyjoin to earth. V/Vg= – D/(1 – D) The Properties of Buck-Boost converter is following from inference as Buck cascaded by Boost In the equivalent circuit: Buck 1:D cascaded by Boost D:1 Pulsate theinput(I) of the Buck converter Pulsate the output (I) of the Boost converter At figure 3. The circuit Describe how the (Buck-Boost) converter is working .This circuit have three terminal switch of cell can be join between the load andthe source in three ways: a-A b-B c-C Buck converter a-C b-A c-B Boost converter a-A b-C c-B Buck-Boost converter

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Figure 3. Rotation of three-terminal cell

IV. APPLICATION AND RESULTS A .Steady state step-down conversion If the Vg is higher than V(out), the Buck-Boost converter working in step down. During at thisstate, Boost converter is turn off, Buck switching chopping at the input voltage and the (rotation no 1) atBuck converteris operating to divide current inductor between regulate of output voltage and output capacitors. The switching configuration is appliedat steady state step-down[6,7]. At figure 4 it can be seen the Buck converter is working and the V(out) is constant at 12V even the (Vin) is 18V The output voltage will be at steady state at 0.6 ms.

Figure 4. Simulation of (Buck- Boost converter) at Buck state

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B. Steady state step-up conversion Ifthe Vg is less than V(out), Buck- Boost converter are operating in step-up mode. During in the mode, Buck is constantly turn off, Boost works to step up input voltage and the (rotation no 2)at Boost converteroperates to connected thecurrent inductor between regulates of output voltages and output capacitors. The switching configuration is applyingat the steady state step-up[6,7]. At figure 5 it can be seen the Boost converter is working and the V(out) is constant at 12V even the (Vin) is 8V The output voltage will be reach at steady state at 0.7ms.

Figure 5. Simulation of (Buck-Boost converter) at Boost state

V. CONCLUSION A new method of multilevel DC-DC converters with Susceptibility of step up and step down converter is offered. The circuit applies and analyzed of the multilevelconverterMulti-voltage converter are proposition as convenient application. Comparing with the strategy to produce in demand voltage, several number of inductors are increasing the number of outputs voltage with several converters. While, the offered topology demand justfor single inductor. The method of steady state isdevelopment and the implementation of the purposed topology is described of these neutralizations. There is no limit for step up or for step down conversion, since the elements are considered ideal. However, in workout, the nonlinearas inductor resistance is limited forthe step up transmutation. The control delineation of theoutput voltage is showed. Several of simulations results are presented properties of explained topology with offered strategy of control. To check the topology and affined strategy of control at laboratory is developed and testing and hold out. The experiments have advantages of load prioritizations. Further, experimentpresentation that utilization of meander inductor and switches after charging the capacities may develop the dynamic response remarkably.

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VI. ACKNOWLEDGEMENTS First and foremost I would like to thank God. You have given me the power to believe in myself and pursue my dreams. I could never have done this without the faith I have in you, the Almighty. I would like to express my deep and sincere gratitude to my research supervisor Dr.ABADAL-SALAM T. HUSSAIN & F. MALEK for giving me the very special opportunity to work on my research paper.

VII. REFERENCES [1] H. A. C. Braga, I. Barbi, “Conversores Estaticos Multiniveis - Uma Revislo”, Revisto do SBA Conbole & AirtoniqBo, vol. 11, no. 01, pp. 20-28, janeiro a abril.de 2000 (in Portuguese). Torado, UFSC, Florianopolis, 1996 (in Portuguese). [2] H. A. C. Braga, “Conversores Multiniveis em Corrente”, Tese de dou-torado, UFSC, Florianopolis, 1996 (in Portuguese). [3] Maksimovic D. and Dhar S., "Switched-Capacitor DC-DC Converters for low power on-Chip applications.” 30th IEEE Power Electronics Specialists Conference, 1999 [4] Jou S.J. and Chen T.L., “On-chip voltage down converter for low power digital system”, IEEETrans. Circuits Syst.II, vol.45, no.5, pp.617-625, May 1998. [5] Zhou Q., Lai F. and Wang Y., “On-Chip Voltage Down Converter Based on Moderate Inversion for Low- Power VLSI Chips”, Proceedings of 6th International Conference on Embedded Systems, China, Jan. 2007, pp433 – 438. [6] T. Senanayake, T. Ninomiya, “High-current clamp for fast-response load transitions of DCDC converter” Proceedings of the 2003 International Symposium on Circuits and Systems,2003. ISCAS '03. Volume 1, 25-28 May 2003 Page(s) I-653-I-656 vol.1 [7] R. Mahadevan, S. El-Hamamsy, W.M. Polivka and S. Cuk, “A converter with three swithched-networks improves regulation, dynamics and control” pp E1.1 E1.19 March-1983.

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