Analysis of PFC BL-SEPIC Converter Based Intelligent Controller Fed BLDC Motor Drive

Transcription

1 Internatonal Journal of ChemTech Research CODEN (USA): IJCRGG, ISSN: , ISSN(Onlne): Vol.11 No.04, pp 81-91, 2018 Analyss of PFC BL-SEPIC Converter Based Intellgent Controller Fed BLDC Motor Drve S.Bensha 1 * & P.Svachandran 2 1 Department of EEE, Sree Sastha Insttute of Engneerng and Technology, Chenna , Inda. 2 Department of EEE, Vel Tech Mult Tech Dr.Rangarajan Dr.Sakunthala Engg College, Chenna , Inda. Abstract : Ths paper presents comparatve study of varous Intellgent controllers for Brdgeless-Sngle Ended Prmary Inductance Converter (BL-SEPIC) fed Brushless DC (BLDC) motor Drve. By adjustment of the DC lnk voltage of the VSI, the speed of the BLDC motor can be controlled. The voltage source nverter s used as an electronc commutator of PMBLDCM. The Brdgeless PFC SEPIC Rectfer performs poer factor correcton and DC voltage control n sngle stage usng only one controller. The most commonly used controller for the speed control of BLDCM s Proportonal Integral (PI) controller. Further, ANFIS controller has the ablty to automatcally learn and adapt th a state of plant. Also, e desgn and mplement sldng mode controller (SMC) and ts performance s compared th PI and ANFIS controller to sho ts capablty to track the error and usefulness of Sldng mode controller n control applcatons. The sldng mode control technque for permanent magnet brushless DC motor s used to mprove ts dynamc performance th hgh accuracy. The Performance of the converter s analyzed and the results are dscussed to arrve at the best suted controller. The drve has been smulated usng the MATLAB/Smulnk envronment and the performance has been studed. Key Words : Brdgeless-SEPIC, Permanent Magnet Brushless DC Motor (PMBLDCM), Proportonal Integral (PI) Controller, ANFIS Controller, Sldng Mode Control (SMC), Poer Factor Correcton (PFC), Voltage Source Inverter (VSI). Introducton The Poer Factor Corrected (PFC) converter plays a vtal role n the area of research n poer electroncs [1]. Ths AC-DC converters provdes stable DC output voltage th mproved poer factor. Ths crtera makes the converter applcable for offlne poer supples and other AC-DC converson applcatons for meetng the gudelnes of varous poer qualty standards [2].These converters fnds applcatons n robotc control, ar condtoners, ashng machnes, lghtng, heat pumps, computers, servers, prnters, TV and VCRs. Conventonally, In case of a dode brdge rectfer (DBR), a hghvalue of the smoothenng capactor s used for feedng the BLDC motor. It dras a hgh peak current from AC mans due to uncontrolled chargng S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): DOI :

2 S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): and dschargng of the DC lnk capactor[3]. Such peaky supply current has a very hgh total harmonc dstorton (THD) of the order of 65-70% hch results n a very poor poer factor (PF) of the order of at AC mans. Such poer qualty ndces are not acceptable thn the lmts of IEC [4].Also, DC lnk voltage s mantaned constant at the DC lnk capactor of the VSI and pulse dth modulaton (PWM) based current control s used for varyng the speed of BLDC motor. It suffers from hgh stchng losses n three-phase VSI because of hgh frequency stchng of PWM sgnals. Moreover, there s an extra assocated cost of the current sensors requred for current control of BLDC motor.such hgh stchng losses are reduced by electroncally commutatng the BLDC motor [5]. Moreover, the speed s controlled by varyng the DC lnk voltage of VSI [5].Ths reduces the stchng losses of VSI and elmnates the requrement of current sensors for PWM based current control of BLDC motor for speed control. Fg.1: Block Dagram The block dagram of the proposed system s shon n Fg.1. Brdgeless PFC converters have ganed mportance due to lo conducton losses at the front end [6-14].Ths s formed by partal or complete elmnaton of thedbr; thereby the conducton losses assocated th t are reduced.among these confguratons, a brdgeless buck converter can provde a voltage buckng operaton and hence the output cannot be controlled over a de range. [6]. A brdgeless boost converter can provde only voltage boostng, therefore, can t be used for derange of voltage control at hgher values of supply voltages [7].Therefore, PFC BL-buck-boost converters are used for control of voltage over a de range [8]. A SEPIC s a good trade-off beteen the buck-boost confguratons havng theadvantages of loer EMI and smplfed lo-sde gate drverdesgn [10-13]. Operaton of PFC BL-SEPIC Fed BLDC Motor Drve A sngle-phase AC supply s gven to DBR folloed by a flter and a brdgeless SEPIC feedng a BLDCmotor. Ths brdgeless-sepic s made to operate n dscontnuous nductor current mode (DICM) such that voltage control and nherent poer factor correcton s acheved at AC mans by means of sngle voltage sensor. Thus a BLDC motor s controlled by combnaton of DBR and PFC converter va a three-phase VSI s shon n Fg.2. The speed of BLDC motor s controlled by adjustng the DC lnk voltage of the VSI va the PFC converter. The VSI s operated n a fundamental frequency stchng mode to acheve an electronc commutaton of the BLDC motor for reducng the stchng losses assocated th t. The operaton of proposed PFC BL-SEPIC s dvded nto to dfferent sectons (.e. postve and negatve half cycles of supplyvoltage) and complete stchng cycle, respectvely [15]. Durng the postve half cycle, stch S 1, nput nductor L 1, output nductor L o1,ntermedate capactor C 1 and dode D 1 conducts and vce-versa for negatve half cycles of supply voltage. When stch (S 1 ) s

3 S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): turned-on, the nput nductor (L 1 ) and output nductor (L o1 ) start chargng. The ntermedate capactor (C 1 ) dscharges through the output sde nductor (L o1 ) and the voltage across t decreases. The dode (D 1 ) remans n non-conductng state and the DC lnk capactor (C d ) supples the requred energyto the VSI fed BLDC motor.when stch (S 1 ) s turned-off, the nput nductor (L 1 ) and output nductor (L o1 ) starts dschargng va dode (D 1 )[15].Moreover, the ntermedate capactor (C 1 ) gets charged n ths mode. The DC lnk capactor (C d ) charges and the voltage (V dc ) across the DC lnk ncreases n ths mode of operaton. In a smlar ay, the operaton for the negatve half cycle ofthe supply voltage can be realzed. Fg.2: PFC based BL-SEPIC fed BLDC motor drve Desgn of PFC BL-SEPIC n DICM The proposed PFC BL-SEPIC [15] s desgned to operate n DICM such that the current flong n output nductors (L o1 and L o2 ) becomes dscontnuous n a stchng perod. The nput voltage, V s of the PFC converter s gven belo t V Sn2 f t 220 2Sn tv Vs m L 314 Where V m represents the peak nput voltage, f L denotes the lne frequency.e. 50 Hz. The nstantaneous output voltage of the flter s gven as, t V Snt 220 2Sn tv Vn m 314 The output voltage, V dc of a BL-SEPIC s expressed nterms of duty rato (D) as V dc D 1 D V n The nstantaneous value of duty rato, D(t) depends on the nput voltage, V n (t) and the requred DC lnk voltage, V dc. Control of front end PFC Converter There are several approaches n varable speed drve control of BLDC motors.in ths paper e made a comparson beteen PI, ANFIS and SMC control of BLDC drves. Ths ork as appled to three controller

4 S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): modes such as PI, ANFIS and SMC to control the speed ofbldcm. The am s to obtan a better performance of control usng MATLAB Smulnk. Smulaton results are presented and analyzed for all the three controllers. (a) PI controller: The proportonal ntegral controller s the most common and useful algorthm n control system engneerng. The feedback loops are controlled usng PI algorthm. Feedback s very mportant n systems n order to attan a set pont rrespectve of dsturbances or any varaton n characterstcs of anyform. PI controller s desgned to correct error beteen the measured process value and a partcular desred set pont n a system [16]. Fg.3: Block dagram of PI Controller The Proportonal (P) and Integral (I) controls the system S, usng the controller C here the controller effcency depends on P and I parameters. A PI speed controller has been chosen th gan parameters Kp and K. The speed of the motor s compared th the reference value and the error n speed sprocessed by the speed controller. The output of the PI controller at any nstant s the reference torque gven by- T ref K p K s ref r Where Tref s the reference torque, K p s the proportonal gan of the PI controller. the PI controller. ref s the reference speed n rad/sec. r s the actual speed nrad/sec. K s the ntegral gan of Fg.3. presents a block dagram for the control scheme of current mplemented by PI controller th a saturaton module. The actual value of current or speed s sensed from the output and sent to proportonal and ntegral terms hch contans the proportonal term th gan and ntegral term th gan. The outputs are summed usng a Sum block and the output s sent to saturaton block for saturaton purpose and output from ths block gves the error beteen the reference value and actual value of the motor. In PI controlled PMBLDC motor startng speed s greater than reference speed hle n no load and onload condton. When loaded, the tme taken for speed to settle at reference speed s less. Speed drop s less hen load s appled. Also, the tme taken for torque to settle at reference torque after the applcaton of load s lo. (b) Sldng Mode Control Sldng mode control (SMC) s a nonlnear control method ncludng strkng propertes of accuracy, robustness, and easy tunng and mplementaton. Ths system s desgned to drve the system states onto a partcular surface n the state space, named sldng surface. Once the sldng surface s reached, sldng mode control keeps the states on the close neghbourhood of the sldng surface. Hence the sldng mode control s a to part controller desgn. The frst part nvolves the desgn of a sldng surface so that the sldng moton satsfes desgn specfcatons. The second s concerned th the selecton of a control la that ll make the

5 S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): stchng surface attractve to the system state. Frst s that the dynamc behavour of the system may be talored by the partcular choce of the sldng functon. Secondly, the closed loop response becomes totally nsenstve to some partcular uncertantes. Ths prncple extends to model parameter uncertantes, dsturbance and nonlnearty that are bounded.[17] Brdgeless SEPIC converter s used for poer factor correcton and the PWM sgnal to the Brdgeless SEPIC convertor s gven by usng SMC algorthm. Error voltage can be avoded by consderng nductor voltage, nductor current, capactor current, DC lnk voltage. Thus t reduces oscllatons and operates under uncertan condtons. It s one of the man advantage of SMC.Ths could be used n several applcatons such as Overhead crane, Marne vehcles, electrohydraulc valve actuator, Combned Cycle etc., (c) ANFIS Controller A typcal archtecture of an ANFIS hch s used s Sugenofuzzy[18] models consst of fve layers that every layer has the node. There are to knd of nodes. One s the adaptve node (square symbol) and the other s the fxed node (crcle symbol) as shon Fg. 4. The mechansm s desgned usng Sugeno hch has to nputs x 1 and x 2 and one output y. For a frst order Sugeno fuzzy model [19],[20], a common rule set th to fuzzy fthen rules s the follong If x 1 s A 1 and x 2 s B 1 Then y 1 = c 11.x 1 + c 12.x 2 + c 10, If x 1 s A 2 and x 2 s B2 Then y 2 = c 21.x 1 + c 22.x 2 + c 20 If α s predcated for to roles are 1 and 2, then can be determned the eght average as belo y 1 y y 2 2 Fg.4: The Archtecture of ANFIS Layer 1: Each neuron n layer 1 s adaptve th a parametrc actvaton functon. Its output s the grade of membershp functon; an example s the generalzed bell shape functon. ( 1 x) 2 1 x c / a b Where [a, b, c] s the parameter set. As the values of the parameters change, the shape of the bell-shape functon vares. Layer 2:.Every node n layer 2 s a fxed node, hose output s the product of all ncomng sgnals. = µ A (x) µ B (y), =1,2

6 S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): Layer 3: Ths layer normalzes each nput th respect to theothers (The th node output s the th nput dvded the sum of all the other nputs). 2 Layer 4: Ths layer s th node output s a lnear functon of the thrdlayer s th node output and the ANFIS nput sgnals. f p x q y r Layer 5: Ths layer sums all the ncomng sgnals. f 1 f1 2 f2 Smulaton Results and Dscusson The block dagram n Fg.1 has been successfully smulated n the MATLAB R2013a smulnk envronment and the follong results have been observed for the BLDC drve fed by PFC Brdgeless SEPIC converter controlled by PI, ANFIS and SMC. The Smulnk dagram as shon n Fg. 5. Fg.5: Smulnk model of PFC Brdgeless SEPIC fed BLDC Motor th SMC The belo Fg. 6 shos the Input voltage, Input current, Poer Factor, Converter output voltage and current, Motor Speed and Converter Effcency th PI Controller.

7 S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): Fg.6: Waveforms of Input Voltage, Input Current, Poer Factor, Converter output voltage and current, Motor Speed and Converter Effcency (th PI) The poer factor s calculated from the poer factor measurement block. Poerfactor s the rato of actve poer to apparent poer. P.F.=cos(ɸ) = VI cos(ɸ)/vi For the Brdgeless SEPIC converter fed BLDC motor drve th PI controller, the poer factor observed s as follos. It reaches value close to unty at rated speed (0.95).The Converter Effcency th PI controller as found to be 91.9%. The belo Fg. 7 shos the Input voltage, Input current, Poer Factor, Converter output voltage and current, Motor Speed and Converter Effcency th ANFIS Controller.

8 S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): Fg.7: Waveforms of Input Voltage, Input Current, Poer Factor, Converter output voltage and current, Motor Speed and Converter Effcency (th ANFIS) The Converter Effcency th ANFIS controller as found to be 92.9% The belo Fg. 8 shos the Input voltage, Input current, Poer Factor, Converter output voltage and current, Motor Speed and Converter Effcency th Sldng Mode Controller.

9 S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): Fg.8: Waveforms of Input Voltage, Input Current, Poer Factor, Converter output voltage and current, Motor Speed and Converter Effcency (th SMC) The Converter Effcency th SMC controller as found to be 93.52% and the Poer Factor as measured as Comparson of Performance Indces beteen dfferent Controllers A comparson of PI, ANFIS and SMC controller s carred out n terms of dfferent parameters. Table 1. Shos the Performance Comparson of PI, ANFIS and SMC controllers th Brdgeless SEPIC Converter fed BLDC motor drve.the Effcency and Poer Factor are found to be greatly ncreased hen controlled th SMC controller.so, We can conclude that SMC Controller s found to be the better choce for Brdgeless SEPIC drven BLDC motor drve n terms of Poer factor and Effcency. Table 1: Performance Comparson of PI, ANFIS and SMC Parameters PI ANFIS SMC Poer Factor Output Voltage 400±10V 400±15V 400±7V Speed(rpm) Effcency (%) Concluson The performance of the proposed BL-SEPIC based BLDC motor drve as compared th three controllers-pi, ANFIS and SMC and smulaton model as developed. The speed of the BLDC motor can be controlled by varyng the DC lnk voltage. Wth ths PFC converter, three phase VSI has been operated n lo frequency stchng mode th reduced stchng losses. A front-end BL-SEPIC operatng n Dscontnuous Conducton mode has used for DC lnk voltage control and th poer factor correcton at AC mans. The SMC controller gves better performance durng dfferent operatng condtons at all speeds as compared to PI

10 S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): and ANFIS. Also t s found to be more robust and approprate control scheme for PFC converters as compared toconventonal lnear controllers. References 1. B Sngh, B N Sngh, A Chandra, KAI-Haddad, A Pandey &D P Kothar, A reve of sngle-phase mproved poer qualty AC-DC converters, IEEE Trans Industral Electroncs, vol50, Oct Electromagnetc compatblty (EMC) - Part 3: LmtsSecton2: Lmts for harmonc current emssons(equpment nput current <16 A per phase), IEC6/ Document, Second Edton, N. Mohan, T. M. Undeland and W. P. Robbns, Poer Electroncs: Converters, Applcatons and Desgn, John Wley and Sons Inc, USA, Lmts for Harmonc Current Emssons (Equpment nput current 16Aper phase), Internatonal Standard IEC , R. Krshnan, Electrc Motor Drves: Modelng, Analyss and Control,Pearson Educaton, Inda, Y. Jang and M. M. Jovanov, Brdgeless Hgh-Poer-Factor Buck Converter, IEEE Trans. Poer Elect., vol.26, no.2, pp , Feb Y. Jang and M. M. Jovanovc, A Brdgeless PFC Boost Rectfer Wth Optmzed Magnetc Utlzaton, IEEE Trans. Poer Electron., vol.24,no.1, pp.85-93, Jan V. Bst and B. Sngh, An Adjustable Speed PFC Brdgeless Buck-Boost Converter Fed BLDC Motor Drve, IEEE Tran. Ind. Electron., vol.61,no.6, pp , June A. Fardoun, E. H. Ismal, A. J. Sabzal, M. A. Al-Saffar, Ne Effcent Brdgeless Cuk Rectfers for PFC Applcatons, IEEE Trans. Poer Electron., vol.27, no.7, pp , July E. H. Ismal, Brdgeless SEPIC Rectfer Wth Unty Poer Factor and Reduced Conducton Losses, IEEE Trans. Ind. Electron., vol.56, no.4,pp , Aprl M. R. Sahd, A. H. M. Yatm and T. Taufk, A ne AC-DC converter usng brdgeless SEPIC, Proc. of 36th IEEE Annual Conf. of Ind. Electron. Socety (IECON), pp , 7-10 Nov M. Mahdav and H. Farzanehfard, Brdgeless SEPIC PFC Rectfer Wth Reduced Components and Conducton Losses, IEEE Trans. Ind. Electron.,vol.58, no.9, pp , Sept J. W. Yang and H. L. Do, Brdgeless SEPIC Converter th a Rpple-Free Input Current, IEEE Trans. Poer Elect., vol.28, no.7, pp , July V. Bst and B. Sngh, A Reduced Sensor PFC BL-Zeta Converter Based VSI Fed BLDC Motor Drve, Electrc Poer System Research, vol. 98,pp , May V. Bst and B. Sngh, An Adjustable Speed PFC Brdgeless-SEPIC fed Brushless DC Motor Drve 2015 IEEE. 16. P. Sojanya et al. PI And Sldng Mode Control For Permanent Magnet Brushless Dc Motor, Internatonal Journal Of Innovatve Technology And Research Volume No. 1, Issue No. 5, August - September 2013, Mrs. S. Mallga, Ms. A. Setha, Control of Brushless DC Motor Drve th BL Luo Converter usng Sldng Mode Control, Volume 5 Issue IV, Aprl 2017IC Value: ISSN: Hdayat, Sasongko Pramonohad, A Comparatve Study of PID, ANFIS and Hybrd PID-ANFIS Controllers for Speed Control of Brushless DC Motor Drve, 2013 Internatonal Conference on Computer, Control, Informatcs and Its Applcatons. 19. Jang.J-S.R, Sun.C.T, Mzutan.E, Neuro-Fuzzy and Soft Computng, Prentce-Hall Internatonal Inc, USA, Hdayat,PH. Sasongko, Sarjya&Suharyanto, Modelng and Smulaton of Adaptve Neuro Fuzzy Inference Systems (ANFIS) forspeed Control of Brushless DC Motor, Proc. CITEE 2011, Yogyakarta,28 July 2011, paper E P. Svachandran, S. Bensha and C.S. Dhanalakshm, Reve on Hgh Step up DC-DC Converter for Hgh Voltage Gan, Mddle-East Journal of Scentfc Research 24 (3) Page No: , 2016 ISSN IDOSI Publcatons, 2016 DOI: /dos.mejsr

11 S.Bensha et al /Internatonal Journal of ChemTech Research, 2018,11(04): Author s Bography 1 S.Bensha, receved her B.E. Electrcal and Electroncs Engneerng and M.E. Poer Electroncs and Drves n 2006 and 2008 respectvely from Anna Unversty. Presently She s orkng as Assstant Professor n Department of Electrcal and Electroncs Engneerng at Sree Sastha Insttute of Engneerng and Technology, Chenna, Inda. She s pursung her Ph.D from Anna Unversty, Chenna. 2 Dr.P. Svachandran receved hs B.E. Electrcal and Electroncs Engneerng and M.E. Poer Electroncs and Drves n 1996 and 1999 respectvely, from Bharathdasan Unversty and Ph.D. Electrcal Engneerng n 2012 from Anna Unversty. Presently he s orkng as a Professor n EEE Dept. of Vel Tech Mult Tech Dr. Rangarajan Dr. Sakunthala Engneerng College, Avad, Chenna. He has 19 years of dverse experence n teachng and corporate ndustry. *****