The paper reports the development of model-based sensorless control methodologies for driving PMSMs using matrix converters. In particular, experimental results show that observer-based state-estimation techniques normally employed for sensorless control of PMSMs using voltage source inverters (VSIs), can be readily exported to matrix converter counterparts with minimal additional computational overhead. Furthermore, zero speed start-up and speed reversal are experimentally demonstrated. Finally, the observer is designed to be fault tolerant such that upon detection of a broken terminal (phase fault), the PMSM remains operational and could be utilized to provide a limp-home capabilit

Bhangu, B S

Bingham, Chris

Snary, P

Stone, D A

English

University of Lincoln Institutional Repository

Sensorles.s Control of PMSM. for decp-..a ROV. excited by Matrix Conwiters I3INGHAM QirisSensorless Control of deep-sea ROVs PMSMs excited by Matrix ConvertersB.S. Bhangu, P. Snary, C.M. Bingham and D.A. StoneUNIVERSITY OF SHEFHIELDDepartment of Electronic and Electrical Engineering,University of Sheffield, Mappin Street,Sheffield, SI 3JD, UK.Tel: +44 / (0)- 1142225195Fax: +44 / (0) - 1142225196E-Mail: bLbhangu@ sheffield.co.ukURL: ht://wwwxsheffield.ac.ukKeywordsMarne, Matrix Converter, Permanent magnet motor, Sensorless control, Vector controlAbstractThe paper reports the development of model-based sensorless control methlodologies for driving PMSMsusing matrix converters. In particular, experimental results show that observer-based state-estimationtechniques nor-mally employed for sensorless conltrol of PMSMs using Voltage Source Inlverters (VSIs)[1,2], can be readily exported to matrix converter counteTparts witi minimal additional computationaloverhead. Furithermore, zero speed stft-up and speed r-eversal are experimenltally demonstrated. Finally,the observer is designed to be fauLlt toler-ant such that upon detection of a broken terminal (phase fault), thePMSM remains operational and could be utilized to provide a limp-lhome capability.IntroductionManufacturers of work-class deep-sea ROVWs, Fig. 1(a), are increasingly looking towards the replacementof traditional hydraulic based drive systems and otler auxiliary equipment such as robot arms, lighting,and cable-laying and burial equipment, by electric-based technologies [3,4]. Although electromagneticmachines have lower power density that their hydraulic counlterparts, electrically based power units havethe potential to offer significant system advaltages in terms of higher reliability, reduced overall systemmass. imnproved control dynamnics ald better energy efficienlcy [3.4]; the latter translating to a netreduction in mass and drag from the umbilical cable connection for power transmission from a surfaceship,During deep-sea operation of the ROV, buoyancy constraints and cooling issues make it highly desirableto operate power electronic drive systems in an oil-filled environment subiect to the high ambient pressure(up to 400bar), as opposed to being housed in a thick-walled metallic pressure vessel subject to nolninalatmospheric pressture Ib(ar). However, capacitors (particldarly electrolytic types) and some industrialgrade semicondtuctor devices are known to be extremely sensitive to presswre dute to their constrLction,and can implode under piessures corTesponding to 3000m sea depth (300bar). As drive systems mustwith-stand z300bar ambient, the components shouldd ideally be able to withstand 1.33x is pressure(z4OObar) to provide an operating safety margin on the system components. Tests investigating electricaland mechanical failure of the power electronic devices by subjecting commercial devices to targetpressures in an oil-filled pressure chamber have been previously attailed, resulting to several devicefailures [4]. For electric thrluLster actuators and servo systems, it is apparent that daltetratives to industryLIt 2005 - Dn.dcn P.1Sens;orIcss Cowol of lIrvlSrvl,; for dcc,-rj'--;. ROVS cxcitcd by Matrix coavc'-ften BINGaAM1 CliriE1?E 2005 Dilv-3dn ISBSN :90-75,815-08-5, I,.IScnsorlcs.s Conuol of PMSMS for dap-scaRO V. exciard by Matrix Convcrtcr.s I3INGHAM CLisFig. 1: (a) Deep-sea (3000m) Remotely Operated Vehicle (ROV) (Photograph courtesy of Perry SlingsbySystems)VE V vcFig. 2: Vector control scheme for PMSMsstandard Rectifier/Voltage Sotrce Inverters (VSIs), and traditional AC/DC converters. are desirable. sincethese topologies require large recactive energy storage colnponents (electrolytic capacitors beingparticularly pressure sensitive). Here tlen, matrix converters, [3,5,6,7,8] present a natural candidate,since, unlike conventional rectifier/inverter counlterparts viz. voltage- and current-source variants,converters based on a switch matrix do not require a two-stage (rectifier/inver-ter) conlversion process, withthe consequential elimination of the intermediate reactive energy storage elemelnt.Moreover, by reducing the number of external wiring/connections between the motor cand invetter byemploying sensorless commutation of PMSMs, whichi traditionally require the use of encoder, resolver orHall-effect signal feedback of rotor position, reliability cal be improved further. The paper will show thatby employing only measured motor terminal quantities and observer-based rotor position estimationschemes, no extenial sensor signal connections (between motor ald inverter) are necessary, since therequired current/voltage transducers (which operate satisfactorily in high-pressure oil-filled environmnents)LOB 2005 - 9nsdcii 1SB1.l 0.2Coau-ol C-f l'Irvlsrvli; for dccp-..tROV -N "ciTzd by Marix Convcr.crs BINGaAM1 MiSDEl 2005 L)i--;c11i ISBSN :9(U1548tf-5 1i9.2Scnsorlcs.s Conu.1 cfPMSMs for dccp-scaRO V. exeked by Matrix Convcrccrs I3INGHAM CLiscanl be sited at the power conlverter within the high-pressure chamber. Elininatinlg the shaft mountedposition sensors also reduces vibration-damage susceptibility with a correspondinlg reduction inmaintenalce requLiremenlt. In addition, it is expected that by using such sclhemes on a typical all-electricwork-class ROV, possessing >6 electric thruster actuators and >6 (min) auxiliary servo motors, willultimately result in a significant saving on connections/cable-mass. Furthermore, removing the necessityfor an integrated rotor position sensor also simiplifies dile motor colstructionl, since dile special sealingrequfrements attributed to supporting correct operation of the sensor/electronics in the motor housing. in aharsh saline enlvironmelt, are eliminated.Observer-based sensorless control of PMSMs using Matrix ConvertersFor servo-type applications, ald those where electromagnetic torque ripple cal have a signific:ant impacton overall product perfor-manlce, vector control schelnes, Fig. 2, are preferred, and sensorless operationmust be achieved using olnly motor terminal quLantities to accurately estimate the rotor position. Althoughcontrol of PMSMs using matrix converters has been previously reported [3], only recently has sensorlessoperation of PMSMs with matrix converters attracted attention [5,6]. Furthermore, it will be shown thatby suitable chloice of matrix converter conmmutation strategy, observer-based sensorless controlmethodologies previously developed for sensorless control of PMSMs using 6-switch VSIs, can beconvenienltly employed in applications where PMSMs a-e excited by matix converters. In this way, theVA VB VCa b c(a)VA VjBa c(b)Fig. 3: Typical conflguration of a 3x3 matrix converter including in-line filter components12K 2005 - Pn.Jcii 1SBt. P.3Coau-ol C-f l'Irvlsrvli; for dxp-..tROV -N "ciTzd by Matrix Conv.-Lwrs BINGaAM1 MiSDEl 2005 L)i--;c11i ISBSN :9(U1548tf-5 i,.3Scnsorlcs.s Conu.1 cfPMSMs for dccp-scaRO V. exeked by Matrix Convcrccrs I3INGHAM CLisAB sAa sAb NsAcC sBa sBb sDc-L-L-T sCa sOb sOca b cInput Filter Matrix ConverterPMSM machine.Fig. 4. Typical configuration of a 3x3 matrix converter including in-line filter componentsadditional belefits attributed to observer based techniques eg. convenient load-torque estimcation forenhanced speed control, operation from zero speed ald speed reversal are inherently accommnodated [1,2].The overall structure of a matrix converter based PMSM control scheme is shown in Fig. 3(a). Bycomparison with Fig. 3(b), the common requirement for control of PMSMs using 6-switch VSIs, andthose of a matrix converter, can be seen. In particular, they both requfre knowledge of rotor position anddemanded V§ and V, and feedback of motor phase currents. A typical configLration of a 3x3 matrixconverter employed including in-line filter components, is shown by Fig. 4.Rotor position estimation in stator fixed reference frameAn EKF is considered for sensorless estilnation of rotor position for a PMSM powered by a mnatrixconverter. A dynamic model of the PMSM in af8 stator-fixed coordinates is considered:d R'F Ke a,d;_R .K+ c sil 0 +df 4 Ls 3 Ls Ls (1)KRp KeBc O¾ SdIt ~d 0O-wdtwhere R, 4, Ke and K, are, respectively, the phase resistance, synchronouLs inductance, back-emf andtorquLe constants; J is the -otor iiertia. B is the motor viscous friction, is the rotor angular velocity. isthe rotor position aid p7 denotes the number of pole pairs. Since onlly terminal qualtities of the mnotor canbe measired, the inputs are defined as = ]', and the mneasured outputs are y=[ic 3]T. Apredictor-corrector scheme is employed to ultimately force the rotor position error to zero. However, it isseen from (1) thlat derivatives of currents are coupled. by non-linear elements in terms of c and 0, and anEKF is considered for effective estimation of the state variables. The reader is directed to [9,10] forcomplete foruLilation of the recursive EKF algorithm employed.12K 2005 - Pn.Jcii 1SBt. P.4Coau-ol C-f l'Irvlsrvli; for dxp-..tROV -N "ciTzd by Matrix Conv.-Lwrs BINGaAM1 MiSDEl 2005 L)i--;c11i ISBSN :9(U1548tf-5 i,.4Scnsorlcs.s Conuol of PMSMS for dap-scaRO V. exciard by Matrix Convcrtcr.s I3INGHAM CLisExperimental ResultsThe presented matrix converter sensorless scheme has been employed to provide sensorless control of a0.75kW, 4-pole PMSM with a base speed of 4000rpm. Measuremnents taken during steady-state operationof the machine with a speed demalnd of 418 rad/s (1000 rpm) are given in Fig. 5; specifically showing.rotor algular velocity, anld importantly. the difference (error) between the measured and observed rotorposition, respectively. The stealy state position error is seen to be 4102 rad. As demonstrated, dieestimates a-e sufficiently accurate for the machine to adequLately operate under closed-loop torque aldspeed control at steady-state.An attractive feature of the EKF for this (application is the ability to maintain obsetrver stability at zerospeed for start-up without incorporating any supplementary open-loop routines. By way of example, Fig. 6shows measured results from die observer wlhen the system is excited widli a step demand from 0 to 209rad/s (500 rpm) at t=Os. As is evident, estimates of speed and position are accurately determined andstability is mainltained with a steady-state position error of approx -0.2 rad. Moreover, it can be seen thatfor tcOs zero speed of the observer estimates is maintained. Of note, however, is fiat position errorsignificcantly increases about zero speed, althogh thle observer/controller combination does not show amydestabilising tendencies.Figure 7, shows the response of the m-otor to a transient change in speed demand from +209 rad/s to -209rad/s (+500 rpm to -500 rpm) at t-Os. It cal be seen that the EKF accurately estimates the speed, Fig.7(a). Although a slight increase of transient error in position estimates is evident, ultimately motorperfonnance is not unduly degraded, Fig. 7(b).A significant impe-diment to the general adoption of position sensorless control of die PMSM excited bymatrix conlverters for applications on deep sea ROVs is the behaviour of the observer in response to afault. ranging fr-om fauLlts due to damage to the umbilical resultinlg in inlput supply faults. to conlvertermcaiftmutions and machinle supply fauilts. Such conditions can provoke instability of the observer estimatesthat can be critical to matrix convet-ter modulation schelnes. Here then. fautlt tolerant imnplelnenltation isproven, such that. upon ocCLrrence of a mnotor open-circuit phase fault, from zero speed, the PMSMremains functional, and is transferred into a safe mode of operation. Figure 8(a) and (b) shows an exampleof a single phase machine termiTnal fault, indicated by the loss of supply to phase B, ald operated fromstart-up to steady-state 125rad/s (300rpm). Phase voltage is monitored at the output terminal of theconvetter prior to the open circuit fault, henlce, is included in the measurelnenlts. Upon detection of thefault the covarialce matrices Q (and R are mnodified such that stability of the observer estimncates is retaLined.Figure 8(c) shows the rotor angtlar velocity whilst operating at 125rad/s (300rpm), and the difference(error) between the measured and observed rotor position, respectively, where a steady state position erroris seen to be r0.4 rad, Fig 8(d). As delmonstmted, the observer does not show any destabilizing tendenciesand the estimated position rema-ins sufficiently accurate for the machine to operate under closed-looptorquLe and speed control, ultimnately allowing the ROV to accomnmodate a "limp-home" fcacility. Figire8(e) shows the measured and estimated currents in the stator fixed referenlce frame.LOB 2005 - 9nsdcii 1SB1.l ItsCoau-ol C-f l'Irvlsrvli; for dccp-..tROV -N "ciTzd by Marix Convcr.crs BINGaAM1 MiSDEl Own5 L)i--;c11i ISBSN :9(U1548tf-5 I,.fScnsor1cs. Conu.1 cfPMSMs for dc.p-scaRO V. exeked by Matrix Convcrccrs I3INGHAM CLis0O 1eF---- t----sU --CI. C) C0 14 C c(a)M :-i ci r,o;ini-drIFR-,i 1- -.t cid riF)- -i.-ri-t n4~-(b)z :-)I.5Lu0-0 5' .".0I-)I.Fj15Fig. 5: Observer-based vector conitrol ofPMSM at 413 radls (1000 rpmi) (a) Measuired and estimnatedspeed (b) Measure-d andI e-stimated rotor position and position errorSD.L-)0p..-D0uC')018.,Li-fii7(a)tinr-~(b)Fig. 6: Zero speed start-up to step demand of 209 rad/s (500 r-pm) at t=-Os (a) Measured -and estimatedspeed (b) Measured anid estima-c-ted rotor position anid position errorI-)[A-',furej-1 itHc-iiL Et v-ia e : :;t ci71 /i-i1t- --4j. t 12i'ilkt 1r e, U)(b)Fig. 7: Measured results of dynamic acceleration through- zero-speed from 209 radls to -209 radls (+500to -500 rpm) (a) Measured and estimated speed (b) Measured and estimated rotor positionl and positionlerror12K 2005 - Pn.Jcii 1SBt. P.627 ..1-(a)1Coau-ol C-f l'Irvlsrvli; for dccp-..tROV -N "ciTzd by Matrix Conv.-Lwrs BINGaAM Mi.LI,Z,7.puiU)Q.11015-F-LLuF.nIF,A-:Ii.it"-'r-7---I =:-2: A-,..1Ellh 2005 L)iv--;dc,-ii ISBN :9(.-758tf,-W-5 i,.6Scnsor1cs. Conuol cfPMSMs for dap-scaRO V. exeked by Matrix Convcrtcrs I3INGHAM CLisJD CIL C.0 Ci. [.1 '2 -1-4 [l.if i(a)1 ]-L L-4 II1L ELiLid iii Lii ~ ~ t13 3i---d cEito(c)U b L. .'ID ID-C ].03 C.D 2tinr(b).1-4 CI.i 0 EEst ir ~t-d i-iJD -11--JI -Ii- L.i-i 11 L JiLIL U.l LI.i U. i 'L(d)iCd iL~ ~~ ~ ~f ltphase~~ ------ phas-cu ren-(c)estimated---- rotor-- ito-aito-err-e)rd-ncurrents-----.--12K 2005 - Pn.Jcii It'3/-4/3--2---11 11 11 I-ECoau-ol C-f l'Irvlsrvli; for dccp-..tROV -N "ciTzd by Marix Convcr.crs BINGaAM Mi.F.-1pLIpmb42 Fp0 "I-2-. C)I-P-L-FEllh 2005 L)iv--;dc,-ii ISBN :9(.-758tf,-W-5 P.7Scnsorlcs.s Conuol of PMSMS for dap-scaRO V. exciard by Matrix Convcrtcr.s I3INGHAM CLisConclusionThe imiplemenltation of 3x3 matrix converter for thle application of deep-sea ROVs, whlere systems areexpected to sustain operation at higlh ambient pressures, up to 300bar, commensurate with operation ofROVs at 3000m is reported. The conventional voltage source inverter (VSI) which traditionally facilitatesmost synchronous machine drives in indushty applications. consist of large dc-lik electrolytic capacitors,that cannot withstand the considered pressures unless enclosed in large air-filled chanbers cat -atmnosphericpressure, which tends to be of high mass. Here, excitcation of PMSMs via matrix converters, whicheliminates large dc-link capacitors, provides an alternative solution. In particular, witlh a view tominimising external cabling/routing requirements, and simplifying motor designs by vitte of not havingto house and seal rotor position sensors and associated electronics in die motor housing, sensorlessoperation of PMSM excited by 3x3 matrix converter is reported. It is shown that observer-basedsensorless schemes, developed for control of PMSMs with traditional VSIs, can be readily applied tovariants driven matix converters, with experimental results showing the benefits of employing suchschemes. Start-up from zero speed and speed reversal are experimentally demonstrated. Finally, a degreeof fault tolerant operation is demonstrated, such that upon occurrence of a phase fault, the PMSM remainsfuLnctional, and the stability of the observer is maintained.References[t] Bhangu, B. S., Willians. C.. Binghlam, C. M.. Coles. J.: 'Nonlinear state-observer techniques for sensorlesscontrol of automnotive PMSMs. including load torque estimation', Proc. EPE 2003, Toulouse, Framce, CD-ROMProceedings.[2] Bhangu, B. S., Williams, C., Bingham, C. M., Coles, J.: 'EKFs and other Nonlinear State-EstimationTechniques for Sensorless Control of Automotive PMSMs', SPEEDAM 2002, Italy, p. C5, 33-38.[3] Bouchiker, S., Capolino, G. A., Poloujadoff, M.: 'Vector Control of a Permanent-Magnet Synchronous MotorUsing AC-AC Matrix Converter', IEEE Trans. on Power Electronics, Vol. 13, No. 6, November 1998.[4] Snary. P., Binghani, C. M., Stone, D. A., and Schofield, N.: 'Comumercia Electronic Devices for Operation inHighl-Pressurc Decp-Sea Drive Systems', PCJM 2001, Numberg, Germany.[5] Tain Hua Liu, Szu Han Chen, Der Fa Chen: 'Design and Implementation of A Matrix Converter PMSM DriveWithout A Shaft Sensor', IEEE Trans. on Aerospace and Electical Systems. Vol. 39, p.228-43, January 2003.[6] Der-Fa-Clhen, Tian-Hua-Liu, Szu-Han-Chen: 'linplenientation of a novel sensorless matrix converter PMSMdrive', 4th-IEEE International Conference on Power Electronics and Drive Systems. IEEE PEDS 2001Indonesia, CD-ROM Proceedings.-No 2001: 718-24 Vol.2.[7] Wheeler, P. W., Rodriguez, J., Clare, J. C., Empringhani, L., Weinstein, A.: 'Matrix converters: a technologyreview', IEEE Trans. on Industrial Electronics. Vol. 49, No. 2, pp.276-88, April 2002.[8] Huber, L., Borojevic, D.: 'Space Vector Modulated Three-Phase to Thiree Phase Matrix Converter withl IputPower Factor Conrection', EEE Trans. on Industrial Applications, Vol. 31, No. 6, 1995.[9] Kalhinm, R. E.: 'A new approach to linear filtering and prediction probleis', Trans. of the ASME - Journal ofBasic Engineering, Series D, pp 35-45, 1982.[10] Bado, A., Bolognani. S., Zigliotto. M.: Effective estimation of speed amd rotor position of a PM synchronousnotor drive by a Kalann filtering technique. Proc. of IEEE Power Electronics Specialist Conference, pp.951-957, 1992.LOB 2005 - 9nsdcii ItSCoau-ol C-f l'Irvlsrvli; for dccp-..tROV -N "ciTzd by Marix Convcr.crs BINGaAM1 MiSDEl Own5 L)i--;c11i ISBSN :9(U1548tf-5 1'.8

A new approach to linear filtering and prediction probleis',

A.: 'Matrix converters: a technology review',

Comumercia Electronic Devices for Operation in Highl-Pressurc Decp-Sea Drive Systems',

Der Fa Chen: 'Design and Implementation of A Matrix Converter PMSM Drive Without A Shaft Sensor',

Effective estimation of speed amd rotor position of a PM synchronous notor drive by a Kalann filtering technique.

EKFs and other Nonlinear State-Estimation Techniques for Sensorless Control of Automotive PMSMs',

EKFs and other Nonlinear State-Estimation Techniques for Sensorless Control ofAutomotive PMSMs',

Nonlinear state-observer techniques for sensorless control of automnotive PMSMs. including load torque estimation',

Nonlinear state-observer techniques for sensorless control ofautomnotive PMSMs. including load torque estimation',

Space Vector Modulated Three-Phase to Thiree Phase Matrix Converter withl Iput Power Factor Conrection',

Szu-Han-Chen: 'linplenientation of a novel sensorless matrix converter PMSM drive',

Vector Control of a Permanent-Magnet Synchronous Motor Using AC-AC Matrix Converter',

Sensorless control of deep-sea ROVs PMSMs excited by matrix converters

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Sensorless control of deep-sea ROVs PMSMs excited by matrix converters

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