Application Control, Speed Control | Motorola M68HC08 manual

Freescale Semiconductor, Inc.

Freescale Semiconductor, Inc.

BLDC Motor Control

Coef_Toff = 0.5 at Running state, Per_Dis = 150 with default s/w setting

3.3.2 Speed Control

The speed close loop control is provided by a well known PI regulator. The required speed is calculated from speed input variable, as explained in Process Desired Speed Setting. The actual speed is calculated from the average of two back-EMF zero crossing periods (time intervals), received from the sensorless commutation control block. The speed regulator output is a PWM duty cycle.

The speed controller works with the constant execution (sampling) period PER_T3_RUN_US. A detailed explanation is provided in Processs Speed Control.

3.4 Application Control

The application can be controlled in two basic modes:

•Manual mode

•PC master software mode

In manual mode, it is controlled by an on-board start/stop switch and speed potentiometer. In PC master mode, it is controlled from a computer using PC master software. In both modes, the individual variables can be observed using the PC master software.

3.4.1 PC Master Software

PC master software was designed to provide the debugging, diagnostic, and demonstration tools for developing algorithms and applications. It consists of components running on PCs and parts running on the target MCU, connected by an RS232 serial port. A small program is resident in the MCU that communicates with the PC master software to parse commands, return status information, and process control information from the PC. The PC master software uses Microsoft1 Internet Explorer as a user interface on the PC.

Designer Reference Manual		DRM028 — Rev 0

50	BLDC Motor Control	MOTOROLA
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Motorola M68HC08 manual Application Control, Speed Control, PC Master Software

Contents

M68HC08 Freescale Semiconductor, Inc For More Information On This Product Sensorless Bldc Motor Control Using MC68HC908MR32 Designer Reference Manual Rev Revision history List of Sections List of Sections Table of Contents Table of Contents List of Figures Title List of Figures List of Tables List of Tables Introduction ContentsBenefits of the Solution Application Functionality Introduction System Description System Concept System Description System Specification Software parameter tuning to a customer motor Software SpecificationSoftware written in C language specifications are listed Software Specifications Hardware and Drive Specifications High-Voltage Hardware Set Specification High Voltage Hardware Set Specifications Motor -Brake Set Low-Voltage Hardware Set Specification Low-Voltage Evaluation Hardware Set SpecificationLow Voltage Evaluation Hardware Set Specifications Low Voltage Hardware Set Specifications Bldc Motor Targeted by This Application Bldc Motor ControlBrushless DC Motor Control Theory Semiconductor, Inc Bldc Motor Control Brushless DC Motor Control Theory Bldc Motor Back EMF and Magnetic Flux 2 3-Phase Bldc Power Stage Why Sensorless Control? Power Stage Motor Topology Stator Winding Equations Indirect Back EMF Sensing Same expressions can also be found for phase a and B Phase Voltage Waveform Effect of Mutual Inductance Mutual Inductance Effect Effect of Mutual Phase Capacitance Detail of Mutual Inductance Effect Mutual Capacitance Model 10. Distributed Back-EMF by Unbalanced Capacity Coupling 11. Balanced Capacity Coupling Back-EMF Sensing Circuit Inc Alignment Starting Back-EMF Acquisition Running Used Control TechniqueSensorless Commutation Control 14. Commutation Control Stages Alignment 15. Alignment Running Freescale Semiconductor, Inc Running Commutation Time Calculation Commutation time calculation is shown in Figure Service of received back-EMF zero crossing 17. Bldc Commutation Time with Zero Crossing Sensing Where Starting Back-EMF Acquisition Freescale Semiconductor, Inc 18. Vectors of Magnetic Fields 19. Back-EMF at Start Up Computation coefficients are different Starting Commutation Time CalculationRunning Commutation Time Calculation, but the following PC Master Software Application ControlSpeed Control Communication with PC Master Software Specifications PC Master Software Communication Commands PC Master Software API Variables Name Type Representing Description Range MotorStatusDef, FailureDef BIT6 Reserved BIT2 Reserved PerSpeedMAXRange and zero crossing period PerZCrosFltT2 SpeedRangeMaxRPM*PerSpeedMAXRange/PerZCrosFltT2 Freescale Semiconductor, Inc MC68HC908MR32 Control Board System Configuration and DocumentationHardware Design For High-Voltage Hardware Set cofiguration Low-Voltage Hardware Set configuration For Low-Voltage Evaluation Motor Hardware Set configurationEVM Motor Board Phase Low Voltage EVM Bldc Motor Components will describe the individual boards High-Voltage Hardware Set Configuration High-Voltage Hardware System Configuration See References Described in MC68HC908MR32 Control Board User’sManual Motorola document order number Low-Voltage Evaluation Motor Hardware Set Configuration Low-Voltage Evaluation Motor Hardware System Configuration Low-Voltage Hardware Set Configuration System configuration for low-voltage hardware set is shown Low-Voltage Hardware System Configuration 1 MC68HC908MR32 Control Board All HW Sets ComponentsReferences 4shows a block diagram of the board’s circuitry Electrical characteristics in -1apply to operation at 25C High-Voltage Hardware Set Components Electrical Characteristics of Control Board1 3-Phase AC/BLDC High Voltage Power Stage Phase AC High Voltage Power Stage Electrical Characteristics of Power Stage Optoisolation Board Electrical Characteristics of the Optoisolation Board Electrical Characteristics EVM Motor Board 3 3-phase Bldc High Voltage Motor with Motor BrakeLow-Voltage Evaluation Motor Hardware Set Components 2 3-phase Low Voltage EVM Bldc Motor Electrical Characteristics of the EVM Motor BoardElectrical Characteristics of the EVM Motor Board Characteristics of the Bldc motor 1 3-Ph AC/BLDC Low Voltage Power Stage Low-Voltage Hardware Set Components Block Diagram 2 3-phase Bldc Low Voltage Motor with Motor Brake Section Introduction Data Flow Main Software Flowchart State DiagramSoftware Design Data Flow Software Variables Software Variables and Defined ConstantsImportant system variables are listed in Table Process Measurement Start/Stop Switch Reading and Start/Stop DecisionSys3Def Main Data Flow Part1 Process Fault Control Fault Stop Process Back, EMF Zero Crossing Sensing Freescale Semiconductor, Inc Main Data Flow Part 2 Alignment, Starting Process Desired Speed Setting Closed Loop Control System Process Alignment Control Processes Commutation and Zero Crossing Preset and SetBldc Speed Control and Calculation Main Software Flowchart Bldc Commutation and Zero Crossing Selection Main Software Flowchart Freescale Semiconductor, Inc Main Software Flowchart Main Software Loop Freescale Semiconductor, Inc Freescale Semiconductor, Inc State Diagram Software Flowchart Interrupts Application State Transitions Initialize Application State diagram for this software is shown in FigureInitialize MCU Stand-By Freescale Semiconductor, Inc Stand-by State Align State Starting Commutation Time Calculation Freescale Semiconductor, Inc 10. Back-EMF Acquisition Commutation Time Calculation Service of CommutationSet Explained in 5.5.5 Back-EMF Acquisition State Service of Received Back-EMF Zero CrossingRunning State Over Current 11. Running State 12. Stop State Fault State Stop State Software Files Implementation NotesSee Figure Software files and structure are described in section Set Bldc Commutation and Bemf Zero Crossing Selection Preset Bldc Commutation and Bemf Zero Crossing SelectionBldc Commutation and Zero Crossing Selection PWM Duty Cycle Bldc Speed Control and CalculationDesired Speed Calculation PWMValMax = DUTYPWMMAX*MCPWMMODULUS Timers Timer Function TIMACh3Int Designer Reference Manual DRM028 Rev 108 Software Design Minimal Application Speed User GuideApplication Suitability Guide Motor’s nominal speed Motor Suitability Maximal Application SpeedVoltage Closed Loop Mutual Inductance Designer Reference Manual DRM028 Rev 112 User Guide Hardware setups are shown in -1, -2, Application Hardware and Software ConfigurationHardware Configuration High-Voltage Hardware Set Configuration Low-Voltage Evaluation Motor Hardware Set Configuration Low-Voltage Hardware Set Configuration Controller Board Settings Software Setup EVM Board SettingsEVM board settings are the same for all hardware platforms Application HC08 Software Files \bldczerocros08MR32\sources\bldc08.c, main program Application PC Master Software Control Files Execute from Evaluation Board Software ExecutionBuild Bldczerocros08mr32MMDS.sx is generated When the software is built, the S-record fileExecute from Pre-programmed MCU Application Control Manual Operating Mode PC Master Software Remote Operating Mode PC Master Software Control Window For More Information On This Product Tuning for Customer Motor User Guide Tuning for Customer Motor Follow-up for Software Customizing to Customer Motor Follow-up for Advanced Software Customizing To have PC master software installed on your PC computer Start the PC master software parameters tuning application 11. PC Master Software Parameters Tuning Control Window Software Parameters Setting Follow-up Labels in the File const.h \bldczerocros08MR32\sources\constcustlv.h, definitions for Software Customizing to Power StageParameters File Selection Example of Software Customizing to Hardware Range 0,infinity Voltage Setting Hardware CustomizingCurrent Setting Hardware Customizing Example of Software Customizing to Hardware Modified maximal measurable voltage is 55 V, so set Detailed description starts here Software Customizing to Motor Voltage and Current SettingsMaximal and Minimal Voltage Limits Setting Range 0,VOLTRANGEMAX Maximal and Minimal Current Limits Setting Range 0,CURRENTRANGEMAXA Range 0,8 Alignment Current and Current Regulator SettingCurrent during alignment state before motor starts Α From Evaluation Board Parameters Tuning with PC Master Software Project FileSet constcustx.h 12. PC Master Software Current Parameters Tuning Window Designer Reference Manual DRM028 Rev 142 User Guide MUSTCHANGEEXPERnn in file constcustx.h Commutation Parameters Commutation time period to discharge coil current ∝s Start-up Constants and Maximal Commutation Period Range -128,127 Start-up PeriodMaximal commutation period limit ∝s Constcustx.h Set #define Percmtstartus in constcustx.h Alignment Current and Current Regulator Setting 6.5.4.3Constcustx.h Ensure Percmtstartus =PERCMTMAXUS /2 #define Speedpiregigain Constcustx.h file 13. PC Master Software Start Parameters Tuning Window Range 0,255 Software Customizing to Motor Speed Control SettingNumber of commutations per motor revolution Range 0,SPEEDRANGEMAXRPM Maximal speed range rpmMinimal speed of the drive rpm Speedminrpm = 0.07 to 0.5SPEEDMAXRPM User Guide 153 Execute from Evaluation Board Start motor see Application Control and PC Master Software Set PC master software control mode and start motor seeRemote Operating Mode PWM frequency setting is provided by PWM Frequency and Current Sampling Period SettingFor the PWM frequency setting, follow the label PWM Frequency Current Sampling Period PWM Frequency SettingPWM period = Periodpwmus = SETPERPWM*2 EQ PERCST1US = Periodpwmus * Setpercs ∝s Conclusion Software Parameters Setting and TuningCANCHANGEPERCURSAMPn in const.h file Current Sampling Instant User Guide 159 Designer Reference Manual DRM028 Rev 160 User Guide Appendix A. References Motor using MC68HC705MC4 document order number AN1627, Motorola Appendix B. Glossary SG40N Glossary Serial communications interface module SCI a module that Designer Reference Manual DRM028 Rev 166 Glossary Freescale Semiconductor, Inc HOW to Reach US USA/EUROPE/LOCATIONS not Listed