TMS570 Active Cell-Balancing Battery …

1 -+-+-+-+-+-+-+Switch MatrixCell- balancing Switch Matrix1 of 71 of 2 SPISPI12 EVM-+-+-+-+BQ76PL455A-Q1 (monitor and protector)Switch MatrixEMB1428Q 1 of 7 SPI-+UARTISOGATE DriverIsolated Bi-Directional DC-DCGPIOTMS570 LaunchPadHost PCStatusUARTSPIGPIOB attery ModuleUSB Connection forLaunchpad power MCU Emulation and UART for VDAC for Current ControlDAC081S1011 TIDUBI0 March2016 SubmitDocumentationFeedbackCopyright 2016,TexasInstrumentsIncorporatedTMS570 ActiveCell-BalancingBattery-ManagementDe signGuideTI DesignsTMS570 ActiveCell-BalancingBattery-ManagementDe signGuideLaunchPad,CodeComposerStudioare trademarksof ,Cortexare registeredtrademarksof othertrademarksare the propertyof DesignsThis TI Designshowsa systemexamplefor an batterycellsand performchargeanddischargefromone batterycell to an usercan viewthe cell statusand control-cell balancingfroma GUI runningon the host DesignFilesTMS570LS0432 ProductFolderBQ76PL455A-Q1 ProductFolderEMB1428 QProductFolderEMB1499 QProductFolderLAUNCHXL-TMS57004 ToolsFolderBQ76PL455A-Q1 EVMGUIT oolsFolderASKOur E2E ExpertsDesignFeatures The DiagnosticFeaturesof TMS570LS0432microcontroller(MCU)Are Enabledto MonitorandReportTMS570LS0432 StatusDuringRun Time.

2 The TMS570LS0432 MCUC onfiguresBQ76PL455A-Q1for MonitoringCell VoltagesandCheckingBQ76PL455A-Q1 StatusDuringRunTime. The TMS570LS0432 MCUA nalyzesthe DataFromAll Cellsand GeneratesActiveCell BalancingCommands. The TMS570LS0432 MCUC ommandsEMB1428 Qfor Cell Balancingand MonitorsEMB1428 QandEMB1499 QStatusDuringRun Time. The TMS570LS0432 MCUC ommunicatesWithHostPC Througha UniversalAsynchronousReceiverand Transmitter(UART)Emulatedby theNextGenerationHigh-EndTimer(N2 HET)Moduleto Displaythe Statusand Controlthe BalancingOperationDuringRun Electricand HybridElectricVehicles(EVs,HEVs,PHEVs,an d mild hybrids) EnergyStorageSystems(ESS) UninterruptiblePowerSupplies(UPSs)

3 E-Bikesand E-ScootersAn IMPORTANTNOTICEat the end of this TI referencedesignaddressesauthorizeduse, intellectualpropertymattersand otherimportantdisclaimersand March2016 SubmitDocumentationFeedbackCopyright 2016,TexasInstrumentsIncorporatedTMS570 ActiveCell-BalancingBattery-ManagementDe signGuide1 SystemDescriptionThis Battery -managementsystem(BMS)exampleillu stratesa TMS570LS0432(an ISO 26262capable)MCUsupportingactivecell balancingbetweenone cell in a 16-cellbatterymoduleand a enabledto monitorthe statusof TMS570LS0432duringrun monitorbatterycell statusthrougha cell dataand generatesa real-timeinterrupt(RTI)timeris configuredto balancingcommandis passedthroughtheserialperipheralinterfac e(SPI)to EMB1428 Qand EMB1499 Qto enablechargeor dischargeof the usercan viewthe cell voltageand otherstatusdataand controlthe systemoperationusinga graphicaluserinterface(GUI)runningon the host PC.

4 TMS570LS0432communicateswith the host PCthrougha UART port emulatedby the softwareaccompanyingthis designis developedand testedon a TMS570LS0432 LaunchPad (LAUNCHXL-TMS57004)and an TMS570LS0432deviceis a high-performance,automotive-gradeMCUwith architectureincludesthe following: DualCPUsin lockstep CPUand MemoryBIST logic ECCon boththe flashand the dataSRAM Parityon peripheralmemories Loopbackcapabilityon peripheralI/OsThe TMS570LS0432deviceintegratesthe ARM Cortex -R4 moreinformation,see March2016 SubmitDocumentationFeedbackCopyright 2016, BQ76PL455A-Q1deviceis an integrated16-cellbattery-monitoringand protectiondevice,designedfor integratedhigh-speed,differential,capaci tor-isolatedcommunicationinterfacesallow up to 16 BQ76PL455A-Q1devicesto communicatewith a host BQ76PL455A-Q1monitorsand detectsseveralfault conditions,includingthe following.

5 Overvoltage Undervoltage Overtemperature CommunicationfaultsSix GPIO portsand eightanalogAUXanalog-to-digitalconverter (ADC)inputsare includedfor additionalmonitoringand secondarythermalshutdownis includedfor moreinformation,see BQ76PL455A-Q1 HardwareOverviewDRIVERLEVELSHIFTSOFTSTAR TDRVRUVLOHV CURRENT MIRRORSHUTDOWN BIAS100 nAFLOATING DRIVER TOP OF BATTERYSTACK (60V MAX) CIRCUITRYDRIVER BIAS CURRENTGENERATORA pprox. VSTACK + (2 X VDDP)CHARGE PUMPVDD5V5V CORE LOGICGNDPVDD5 VRSTVDDIOCSCLKSDISDOFAULT_INTMACHINEEMB1 499 INTER-FACE5VI/O1 MHzCLOCKSPIINTER-FACESTATEbg_goodSWITCH _ENSLEWPORCLKLEVEL [ ] March2016 SubmitDocumentationFeedbackCopyright 2016, EMB1428 QswitchmatrixgatedriverIC is designedto workwith the EMB1499 QDC-DCcontrollerICto supportTI s switchmatrix-basedactivecell balancingschemein a floatingMOSFET gatedriversnecessaryfor balancingup to sevenbatterycellsconnectedin a EMB1428 QICs may be usedtogetherto balancea stackwith morethan7 EMB1428 Qintegratedcircuitinterfaceswith the EMB1499 QDC-DCcontrollerto controland enablechargingand EMB1428 Qusesan SPI bus to acceptcommandsfromthe maincontrolleron whichbatterycell shouldbe chargedor dischargedand to reportany faultsto the moreinformation.

6 See EMB1499 QbidirectionalcurrentDC-DCcontrollerIC workswith the EMB1428 QswitchmatrixgatedriverIC to supportTI s switchmatrix-basedactivecell balancingschemefor a EMB1499 QdeviceprovidesthreePWMMOSFET gatesignalsto a bidirectionalforwardconverterso that its outputcurrent,eitherpositiveor negative,is regulatedarounda inductorcurrentis channeledby the EMB1428 Qdevicethroughthe switchmatrixto thecell that mustbe chargedor a typicalscheme,the EMB1499Q-basedforwardconverterexchangese nergybetweena singlecell and the batterystackto whichit belongs,with a maximumstackvoltageof up to 60 V. The switchingfrequencyis fixedat 250 EMB1499 Qdevicesensescellvoltage,inductorcurrent ,stackcurrent,and (Bias, LDOs, UVLO,Fault Logic)VSENSE_LSVSENSE_HSVSETDIRCELLPLUST MWDORLDORC ontrollerPVINFPGNDFVINPGNDPGNDFGNDAGATE_ HS1 PWM_CLAMPGATE_HS2 GATE_LSDONEFAULT[2.]

7 0]PWM_HS1 PWM_HS2 PWM_LSILIMIT (HS and LS)FAULTCLKDIR (HS and LS) March2016 SubmitDocumentationFeedbackCopyright 2016,TexasInstrumentsIncorporatedTMS570 ActiveCell-BalancingBattery-ManagementDe signGuideThe EMB1499 Qdevicealso providesan activeclamptimingsignalto controlan externalFET driverforthe EMB1499 Qdeviceis enabledand disabledby the the EMB1499 Qdeviceare communicatedto the EMB1428 Qdevicethroughthe DONEand moreinformation,see EMB1499 QHardwareOverview-+-+-+-+-+-+-+Switch MatrixCell- balancing Switch Matrix1 of 71 of 2 SPISPI12 EVM-+-+-+-+BQ76PL455A-Q1 (monitor and protector)Switch MatrixEMB1428Q 1 of 7 SPI-+UARTISOGATE DriverIsolated Bi-Directional DC-DCGPIOTMS570 LaunchPadHost PCStatusUARTSPIGPIOB attery ModuleUSB Connection forLaunchpad power MCU Emulation and UART for VDAC for Current March2016 SubmitDocumentationFeedbackCopyright 2016,TexasInstrumentsIncorporatedTMS570 ActiveCell-BalancingBattery-ManagementDe signGuide2 GettingStartedHardwareFigure5 showsthe blockdiagramof activecell HardwareCell balancingis a methodfor extendingbatteryrun time and batterylife.

8 The activecell balancingisbasedon the activeenergytransferat the cell that mustbe chargedor this BMSexample,the energyis transferredbetweenone cell in a 16-cellbatterymoduleand an external12-Vbatteryfor thesimulationof an EV EM1402 EVMis designedas the batterymonitorand cell cell-monitoringarchitectureis basedon the BQ76PL455A-Q1IC. The TMS570LS0432 MCUconfiguresand commandsthe BQ76PL455A-Q1IC to measurethe voltagesof all cellsand readthe errorstatusthroughthe this BMSexample,the averageof the cell voltageis calculatedand the cell with the mostvoltagedeviationfor the averageis selectedfor chargeor TMS570LS0432 MCUcommandstheEMB1428 QIC to chargeor dischargethroughthe SPI EMB1428 QIC is designedto controlchargingor dischargingup to are usedin EM1402 EVMto chargeor EM1402 EVMis designedwith one EMB1499 QIC to allowchargeor dischargeof one batterycell at a usercan controlthe operationof the systemfroma GUI runningon the host PC.

9 This GUI is developedfor thereleasedBQ76PL455A-Q1 EVMand requiresa the TMS570LS0432 MCU,thereisonly one UART port that is usedfor the communicationwith the secondUARTis createdby the N2 HETtimermoduleon the emulatedUART runsat a baudrate of 250 kHz and doesnot incurany March2016 SubmitDocumentationFeedbackCopyright 2016,TexasInstrumentsIncorporatedTMS570 ActiveCell-BalancingBattery-ManagementDe signGuideFigure6 showsthe hardwareconnectionbetweenTMS570LS0432 LaunchPadand port controlsfour ICs on EM1402 EVM:threeEMB1428 QICs for chargingor dischargingto thebatterycellsand digital-to-analogconverter(DAC)DAC081S10 1 CIMK/NOPBfor controllingthe the EM1402 EVM,the SPI chip selectsignalsare generatedby a shift outputof the shift registerIC is controlledby the SPI dataand two TMS570LS0432 GPIO signals.

10 GIOA4for strobeand GIOA7for TMS570LS0432 LaunchPadand EM1402 EVMC onnectionOn the TMS570LS0432 LaunchPad,the TMS570LS0432 UARTis connectedto the XDS100V2FT232 HLIC for userto communicatewith the TMS570LS0432devicethrougha USBUART port on the host connectionmustbe replacedby the UART emulatedby the showstherequiredmodificationof the TMS570LS0432 LaunchPadModificationStartupInitialize TMS570 Initialize PL455 Initialize EB1428 Channel restore flag set?Host message ready?ACB enabled?Restore PL455 channel registers from RAM copyCall HostMessageProcess() function to process host message, Send/receive PL455 data. Return data to host Call ActiveBalancing() function to run ACB according to the ACB time tick from a RTI compare March2016 SubmitDocumentationFeedbackCopyright 2016,TexasInstrumentsIncorporatedTMS570 ActiveCell-BalancingBattery-ManagementDe signGui