Simulation and Closed Loop Control of Multilevel DC-DC Converter for Variable Load and Source Conditions

Transcription

1 ISSN(Onlne): ISSN (Prnt) : (An ISO 3297: 27 Certfed Organzaton) Vol. 4, Issue 3, March 216 Smulaton and Closed Loop Control of Multlevel DCDC Converter for Varable Load and Source Condtons Heena I. Mansur 1, Dr.Yagnesh B. Shukla 2, Madhusudan V. Gohl 3 M.E Student, Dept. of E&C, SVIT, Vasad, Gujarat, Inda 1 Professor & H.O.D, Dept. of E&C, SVIT, Vasad, Gujarat, Inda 2 Assstant Professor, Dept. of EEE, VIER, Vadodara, Gujarat, Inda 3 ABSTRACT: Power electroncs converters are used n many feld of electrcal system. The converter has to face many problems n power conversons and other relablty and stablty lmts. In DC to DC converter the man problem s voltage regulaton. Ths project presents a novel nonsolated negatve output DCDC multlevel converter CUK. The proposed converter topology s sutable for photovoltac applcatons where two voltages are needed at the same tme wth opposte polarty. The proposed DCDC converter topology s the multlevel CUK converter. Negatve output voltage s obtaned from multlevel CUK converter. The gan of the converter can be ncreases by addng approprate number of capactors and dodes wthout dsturbng the man crcut. The proposed converter wll be mplemented for DC load and PI controller s used to control the output voltage accordng to the requrement. The Proposed converter topology s smulated n MATLAB/SIMULINK envronment. KEYWORDS: Multlevel Cuk converter; Close loop control; Desgn of converter I. INTRODUCTION Power electroncs s the applcaton of soldstate electroncs to the control and converson of electrc power. It also refers to a subject of research n electronc and electrcal engneerng whch deals wth the desgn, control, computaton and ntegraton of nonlnear, tmevaryng energyprocessng electronc systems wth fast dynamcs. The frst hgh power electronc devces were mercuryarc valves. In modern systems the converson s performed wth semconductor swtchng devces such as dodes, thyrstors and transstors, poneered by R. D. Mddlebrook and others begnnng n the 19s. In contrast toelectronc systems concerned wth transmsson and processng of sgnals and data, n power electroncs substantal amounts of electrcal energy are processed. An AC/DC converter (rectfer) s the most typcal power electroncs devce found n many consumer electronc devces, e.g. televson sets, personal computers, battery chargers, etc. The power range s typcally from tens of watts to several hundred watts. In ndustry a common applcaton s the varable speed drve (VSD) that s used to control an nducton motor. The power range of VSDs starts from a few hundred watts and end at tens of megawatts. The power converson systems can be classfed accordng to the type of the nput and output power AC to DC (rectfer) DC to AC (nverter) DC to DC (DCtoDC converter) AC to AC (ACtoAC converter) DC to DC power converters lke SMPS provdes varable output voltage and current accordng to requrements. the man advantage of ths converter s proper control. Control strategy of converter s very easy but voltage regulaton of the system s very poor. Man problem of the system s varaton n the voltage to lower to hgher lmt whch can control by the control strategy. If proper control strategy s used to control the converter though voltage and current fluctuaton affects load performance durng lower to hgher voltage regulaton. Multlevel converters are used to mprove the voltage regulaton of the output as well overcome the lmtaton of sngle converter. There are few advantages of the multlevel converter whch as lsted as below: Copyrght to IJIRCCE DOI: 1.168/IJIRCCE

2 ISSN(Onlne): ISSN (Prnt) : (An ISO 3297: 27 Certfed Organzaton) Vol. 4, Issue 3, March 216 Bandwdth of output s hgh. Reduce the huge ratngs of component as they are spted nto small groups. Mnmum to maxmum value dfference ncreases whch can provdes better voltage regulaton. Output voltage and current rpples can bereduced. A.Multlevel Topology In ths paper a novel non solated dual output hybrd DCDCmultlevel converter s proposed. The proposed converter topology provdes a sutable soluton to obtan two outputs wth opposte polarty from a sngle DC source. Fg.1 Multlevel converters [3] The proposed DCDC converter topology s the combnaton of two hgh gan multlevel DCDC converters, one s multlevel boost converter and another s multlevel cuk converter. DCDC Multlevel boost converter provdes postve polarty output voltage and DCDC multlevel cuk converter provdes negatve polarty output voltage. Crcut dagrams of multlevel boost converter and multlevel cuk converter s shown n Fg1 (a)(b). The man advantage of proposed topology s two output voltages are obtaned by controllng sngle swtch. Hence only one gate drver crcut s needed to drve the proposed converter. Voltage levels of both outputs can be ncreases by connectng more number of dodecapactor stacks wthout modfyng the man crcut. The voltage gan of proposed converter s depends upon the number of levels and duty cycle of swtch. B. Modes of operaton The operaton of non solated dual output hybrd DCDCconverter can be dvded nto two modes, one when swtch s conductng and another when swtch s not conductng. When swtch S s conductng, nductor L1 s charged by VIN. Capactor C2 s charged by voltage across C1 through dode D2. At the same tme CC2 s charged by voltage across CC1 through DC2. When D4 and DC4 s forward based capactors C2, C4 and CC2, CC4 are charged by C1, C3 and CC1, CC3 respectvely. Capactors C2, C4, C6 and CC2, CC4, CC6 are charged by voltage across C1, C3, C and CC1, CC3, CC respectvely, when D6 and DC6 are forward based. When D8 and DC8 are forward based capactors C2, C4, C6, C8 and CC2, CC4, CC6, CC8 are charged by voltage across C1, C3, C, C7 and CC1, CC3, CC, CC7 respectvely. Fnally L2 s charged by voltage across CC1, CC3, CC, CC7 and CC9 through swtch S. The operaton modes and drecton of current when swtch S s conductng s shown n Fg.2 (ae). When swtch S s not conductng, capactors C1 and CC1 are charged by nput supply VIN and nductor L1. When D3 and DC3 are forward based, capactors C1, C3 and CC1, CC3 are charged by VIN, L1, C2 and VIN, L1, CC2 respectvely. When D and DC are Copyrght to IJIRCCE DOI: 1.168/IJIRCCE

3 ISSN(Onlne): ISSN (Prnt) : (An ISO 3297: 27 Certfed Organzaton) Vol. 4, Issue 3, March 216 forward based, capactors C1, C3, C and CC1, CC2, CC are charged by VIN, L1, C2, C4 and VIN, L1, CC2, CC4 respectvely. When D7 and DC7 are forward based, capactors C1, C3, C, C7 and CC1, CC3, CC, CC7 are charged by VIN, L1, C2, C4, C6 and VIN, L1, CC2, CC4, CC6 respectvely. When D9 and DC9 are forward based, capactors C1, C3, C, C7, C9 and CC1, CC2, CC, CC7, CC9 are charged by VIN, L1, C2, C4, C6, C8 and VIN, L1, CC2, CC4, CC6, CC8 respectvely. At the same tme nductor L2 s dscharged. The operaton modes and drecton of current when swtch S s not conductng. [3] (a) (b) (c (d) (e) (f) Copyrght to IJIRCCE DOI: 1.168/IJIRCCE

4 ISSN(Onlne): ISSN (Prnt) : (An ISO 3297: 27 Certfed Organzaton) Vol. 4, Issue 3, March 216 (g) (h) () (j) Fg.2 (ac) Operaton modes and drecton of current when swtch S s conductng. (de) Operaton modes and drecton of current when swtch S s conductng. (fj) Operaton modes and drecton of current when swtch S s not conductng [3] II. SIMULATION OF CUK CONVERTER Controller desgn for any system needs knowledge about system behavour. The MATLAB/SIMULINK software package can be advantageously used to smulate power converters. Ths study ams at development of the models for all basc converters and studyng ts open loop response, so these models can be used n case of desgn ofany close loop scheme. Crcut dagram of open loop CUK converter s shown n fg.3. Copyrght to IJIRCCE DOI: 1.168/IJIRCCE

5 E k a g C ISSN(Onlne): ISSN (Prnt) : (An ISO 3297: 27 Certfed Organzaton) Vol. 4, Issue 3, March 216 Contnuous powergu Scope2 Current Measurement1 L1 C1 L2 C urrent Measurement2 Voltage Measurement Scope1 v Vs IGBT/Dode Pulse Generator1 m Dode m C 2 Load Voltage Measurement1 v Scope3 Fg.3 Smulaton of open loop CUK converter Smulaton crcut of CUK converter s shown n fgure above. Ths smulaton s prepared n MATLAB envronment and results of the smulaton s shown n ths chapter. Values of the smulaton are shown n the table below: Name of parameter Value Name of component Value Input Voltage 12V Inductor l1 18μH Output voltage 24V Capactor C1 2μC Output current A Inductor L2 1μH Swtchng frequency 2KHz Capactor C2 22μC Smulaton Results: Table1. Lst of parameter 1 1 C u r r e n t V o l t a g e C u r r e n t ( A ) V o l t a g e ( V ) Fg.4Output current and output voltage of Fg. Input Current and Input Voltage of Cuk Copyrght to IJIRCCE DOI: 1.168/IJIRCCE

6 g C E ISSN(Onlne): ISSN (Prnt) : Cuk converter converter M a g n t u d e (An ISO 3297: 27 Certfed Organzaton) Vol. 4, Issue 3, March V o l t a g e V C u r r e n t ( A ) Fg.6 (a) Duty Cycle generaton (b) Voltage across the swtch and current through swtch III. CLOSED LOOP MULTILEVEL CUK CONVERTER L2 V n Vo ut Scope 9 C 3 Vout Iout C 6 Sco pe1 Iout Vre f1 C 4 Iout Man ual Sw tch 2 C 8 Su bsystem C 2 Load2 Load1 v Vout Vou t Contnuous powe rgu C 1 C 9 I n Vn In L1 C 1 Vn v Vs D Fro m SWITC H Dode Fg.7 Smulaton of closed loop multlevel CUKconverter Copyrght to IJIRCCE DOI: 1.168/IJIRCCE

7 ISSN(Onlne): ISSN (Prnt) : Smulaton Results (An ISO 3297: 27 Certfed Organzaton) Vol. 4, Issue 3, March 216 V o l t a g e ( V n ) V o l t a g e ( V ) C u r r e n t ( A ) Fgure 8: (A) Input voltage (B) Ref. voltage and load voltage (C) Load current n constant nput varable load condton Vout Fgure 9: Fgure 1: (A) Input Voltage (B) Ref. voltage and load voltgae (C) Loacurrent n varable nput and varable load condton IV. RESULTS ANALYSIS From the results shown, the output voltage remans constant n every varable condtons. In the frst condton the load condton s vared but the output voltage remans same. Same way n second results the varaton of nput voltage wth respect to output s shown wth varable load condtons. Our output voltage wll remans consent as reference provded to t. Multlevel topology for CUK converter s much more relable system whch s used n any varable DC voltage applcaton. Ths converter provdes fne voltage regulaton to meet the voltage requrement and control the speed of DC motor. There are some more objectves whch are lsted as bellow: To acheve hgh voltage regulaton. Decrease ratngs of component Decrease the sze of converter. Decrease number of component. REFERENCES [1] MankantanE;.Jutty and Maran K. Kazmerczuk, Senor Member, IEEE, Effcency of the Transformer Cuk PWM Converter,IEEECH3368/93/ 639,1993. [2] P.NagalakshmKannaand Dr.B.Meenaksh Analyss and Desgn of DC DC/AC Non Isolated Cuk Converter usng Sldng Mode Controller,Internatonal Conference on Crcut, Power and Computng Technologes [ICCPCT],21 [3] Mahajan SagarBhaskarRanjana, NandyalaSreeramulaReddy and RepalleKusalaPavan Kumar NonIsolated Dual Output Hybrd DCDC Multlevel Converter for Photovoltac Applcatons, 2nd Internatonal Conference on Devces, Crcuts and Systems (ICDCS),214 [4] MaosenShen, Fang ZhengPengand Leon M. Tolbert, IEE members, Multlevel DC DC Power Converson System Wth Multple DC Sources, IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 23, NO. 1, JANUARY 28. [] R. Srranjan, A. ShreeBharath and S. Jayalaltha, Desgn of Cuk Converter Powered by PV Array, Research Journal of Appled Scences,Engneerng and Technology 6(): , 213 [6] M. H. Rashd, Power Electroncs: Crcuts, Devces, and Applcatons, Book, Prentce Hall Inc., 3ed Edton, 211. [7] K. B. Khanchandan, Power Electroncs, Book, TATA McGRAW HILL, 2nd Edton, 211. [8] Muhammad Al Mazd, The 81 mcrocontroller and Embedded System, Book, PEARSON, 2nd Edton, 26. [9] EbrahmBabae, Mehd Mahae, Improvng Output Voltage of the Three Phase SxSwtch Inverters TELKOMNIKA, Vol.9, No.3, December 211, pp. 497~2, ISSN: [1] S.UmamaheswarP.R.ThakuraR.K.Keshr, Hardware Development of Voltage Source Inverter for Hybrd Electrc Vehcle /11$26._c 211 IEEE. [11] Mohamed H. Saed, M. Z. Mostafa, T. M. AbdelMonem and H. A. Yousef, new 13space vector dagram for the threephase Sxswtches voltage source nverter nternatonal conference on communcaton, computer and power (cccp'9) muscat, february 118, 29 [12] K. Rajasekara, Power electroncs for the future of automotve ndustry, Proceedngs of PCIMEur., Nuremberg, Germany, May 22. [13] Zhong Du et al, DC AC cascaded hbrdge multlevel boost nverter wth no nductors for electrc/hybrd electrc vehcle a pplcatons, IEEE Trans. on Industry Applcatons, vol. 4, no.3, May/June 29. [14] K. A. Corzne, F. A. Hardrck, and Y. L. Famlant, A cascaded multlevel hbrdge nverter utlzng capactor voltages sources, n Proc. of IASTED Conference, Palm Sprngs, CA, 23, pp Copyrght to IJIRCCE DOI: 1.168/IJIRCCE