AN1857 Freescale Semiconductor, Inc. 3-Phase Induction Motor
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AN1857
Freescale Semiconductor, Inc.
3-Phase Induction Motor Control System Based MC68HC908MR32
Bill Lucas Berringer Motorola Microcontroller Division Austin, Texas Software Written Radim Visinka, Petr Lidak, Pavel Kania, Petr Stekl Roznov System Application Laboratory Roznov, Czech Republic
Introduction
microcontroller technology enabled design energyefficient cost-effective motor control systems. Using microcontrollers (MCU) with specialized pulse-width modulator interfaces integrated protection architecture allows reasonable approach reduce total system cost increase overall performance. This application note describes such system based Motorola MC68HC908MR32 (MR32) motor control specific MCU, optoisolation, power electronics. discussion MR32 MCU, hardware design control board, optoisolation interface, power electronics, required software control 3-phase induction motor presented.
Motorola, Inc., 2000
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Freescale Semiconductor, Inc. Application Note Look MC68HC908MR32 Motor Control Microcontroller
MR32 member low-cost, high-performance M68HC08 (HC08) Family 8-bit MCUs that designed specifically midrange motor control applications. Motorola HC08 Family MCUs enhanced, upward object code compatible architecture that evolved from M68HC05 (HC05) Family. MCUs family enhanced HC08 central processor unit (CPU08) that includes addressing modes, many instructions, performance improvements existing instructions that result from introduction instruction pipelining. MCUs HC08 Family available with variety package types, input/output (I/O) modules, various memory sizes types. Features MR32 motor control include: High-performance M68HC08 (CPU08) architecture Fully upward-compatible object code with M68HC05, M146805, M68HC(7)05 Families 8-MHz internal frequency Kbytes on-chip FLASH memory FLASH data security bytes on-chip random-access memory (RAM) 12-bit, 6-channel center-aligned edge-aligned pulse-width modulator (PWMMC) module Serial peripheral interface module (SPI) Serial communications interface module (SCI) 16-bit, 4-channel timer interface module (TIMA) 16-bit, 2-channel timer interface module (TIMB) Clock generator module (CGM) Digitally filtered low-voltage inhibit (LVI) 10-bit, 10-channel analog-to-digital converter (ADC)
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Application Note Look MC68HC908MR32 Motor Control Microcontroller
System protection features include: Optional computer operating properly (COP) reset Low-voltage detection with optional reset Illegal opcode detection with optional reset Illegal address detection with optional reset Fault detection with optional disabling Low-power design, fully static with wait mode Master reset (RST) power-on reset (POR) 64-pin plastic quad flat pack (QFP)
Freescale Semiconductor, Inc.
Some CPU08 features include: Enhanced M68HC05 programming model Extensive loop control functions addressing modes (eight more than HC05) 16-bit index register stack pointer Memory-to-memory data transfers Fast multiply instruction Fast 16/8 divide instruction Binary-coded decimal (BCD) instructions Optimization controller applications Improved language support
This application note does discuss great detail each modules resident MR32. Figure shows block diagram MR32. detailed description MR32, refer 68HC908MR32, 68HC908MR16 Technical Data: Advance Information, Motorola document order number MC68HC908MR32/D. MR32's PWMMC module protection features make device excellent choice embedded motor control system. review PWMMC module features included here.
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Freescale Semiconductor, Inc. Application Note
10-CH 10-BIT
TIMA 4-CH TIMB 2-CH PWM1 PWM2 PWM3 PWM4 PWM5 PWM6
CPU08
FLASH BYTES PWMMC
Freescale Semiconductor, Inc.
POLARITY SIGNALS
FAULT INPUTS
Figure MC68HC908MR32 Block Diagram
MC68HC908MR32 Pulse-Width Modulator
pulse-width modulator module (PWMMC) resident MR32 specifically designed provide pulse-width modulated outputs drive power stage connected servo, brushless 3-phase motor system. PWMMC module partitioned configured several ways, depending specific motor control application. Figure shows block diagram PWMMC module referenced throughout this explanation PWMMC generator. Features MR32 include: Three complementary pairs independent signals Complementary mode features include: Dead-time insertion Separate top/bottom pulse-width correction current sensing programmable software bits Edge-aligned center-aligned signals signal polarity 20-mA current sink capability outputs Manual output control through software Programmable fault protection
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Application Note MC68HC908MR32 Pulse-Width Modulator
PRESCALER GENERATORS UP/DOWN COUNTER PRESCALER CONTROL MODE SELECT DEADTIME INSERTION DIRECT OUTPUT CONTROL DISTORTION CORRECTION RELOAD INTERRUPT INTERRUPTS OUTPUT
FAULT PROTECTION
PWM1 PWM2
COMPARATORS
FAULT PARTITIONING
POLARITY CONTROL
PWM3 PWM4
Freescale Semiconductor, Inc.
DOUBLE BUFFERED REGISTERS
FAULT MODE SELECT
HIGH CURRENT DRIVERS
PWM5 PWM6
MOTOR CURRENT POLARITIES
SYSTEM FAULTS
Figure PWMMC Module Block Diagram most important features PWMMC ability "shut itself down" when system fault detected. When dealing with system that potentially could have hundreds amps peak current, reacting faults such overcurrent overvoltage conditions absolute necessity. Fault protection discussed here first. then work from outputs inward. discussion inputs follows. outputs PWMMC generator configured individual pulse-width modulated signals where each output controlled independent output. Another option configure outputs pairs, with outputs complementary not, driving complementary bottom transistors power stage becomes easy task. outputs PWMMC capable sinking That drive capability allows direct drive optocouplers without need additional drivers. prevent erroneous signals from being output from PWMMC module while loading values, bulk registers double buffered output inhibited until control register, load okay (LDOK), set, indicating okay output values.
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Freescale Semiconductor, Inc. Application Note
Fault Protection Conditions arise external drive circuitry, requiring that signals become inactive immediately. These conditions include overcurrent, overvoltage, overtemperature, other error conditions. four fault input pins MR32's PWMMC module configured react number different ways, upon detection fault. Each fault input interrupt vector. fault conditions, output generator forced known inactive state. number fault control recovery options available systems architect. some cases, desirable selectively disable PWM(s) solely with software. Manual automatic recovery mechanisms available that allow certain acceptable fault situations occur, such starting motor using fault input limit maximum startup current. fault inputs partitioned MR32 used control multiple motors.
Freescale Semiconductor, Inc.
Output Alignment
Depending system design, there choice between edge- center-aligned signals output from MR32's generator. counter uses value timer modulus register determine maximum count. center-aligned mode, 12-bit up/down counter used create period. resolution center-aligned mode clock periods (highest resolution processor speed MHz). period will equal [(timer modulus) (PWM clock period) edge-aligned mode, 12-bit up-only counter used create period. Therefore, resolution edge-aligned mode clock (highest resolution is125 processor speed MHz). Again, timer modulus register used determine maximum count. period will equal [(timer modulus) (PWM clock period)].
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Application Note MC68HC908MR32 Pulse-Width Modulator
Counter Timebase
permit lower frequencies, prescaler provided which will divide clock frequency This prescaler buffered will used generator until LDOK located control register reload cycle begins. When generating sine waves motor, interrupt routine typically used step through sine table located FLASH memory, scale that sine value, output result system from generator. rate which sine table scanned derived from interrupt from generator. module programmed provide interrupt rate every one, two, four, eight reload cycles. some cases, user desire bypass generator directly control outputs. mechanism exists disconnect generator from outputs directly control outputs. When this mode used, generator continues run; however, normal output disabled, overridden direct output. When generator used complementary mode, automatic dead-time insertion provided prevent turning both bottom inverter transistors same phase same time. When controlling dc-to-ac inverters, bottom PWMs pair must never active given time. bottom transistors turned simultaneously, large currents will flow through transistors they attempt discharge supply voltage. transistors could weakened destroyed. Simply forcing PWMs inversions each other always sufficient. Since time delay associated with turning transistors motor drive, there must "dead-time" between deactivation power transistor activation opposite transistor bottom pair. Dead-time specified dead-time write-once register. This 8bit value specifies number clock cycles deadtime.
Load Operations
Freescale Semiconductor, Inc.
Direct Output Control
Dead-Time Insertion
CAUTION:
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Freescale Semiconductor, Inc. Application Note
Motor Phase Current Polarity Sensing Inserting dead-time protect top/bottom inverter transistors motor drive system almost always necessity induction motors. However, inserting this dead-time does come without price. instance, when dead-time inserted, motor voltage allowed float momentarily during dead-time interval, creating distortion motor's current waveform. This distortion aggravated dissimilar turn-on turn-off delays bottom transistors. Three current sensing input pins MR32 labeled IS1-IS3. These inputs sampled during dead-time period. user needs provide current direction sensing hardware feed sensing hardware outputs into IS1-IS3 inputs. software then will compute compensated values place values odd/even register pair. From current direction sensing information, module automatically selects either even numbered value register used generator, thus greatly improving upon sine wave output quality from power stage.
Freescale Semiconductor, Inc.
System Hardware
system consists several printed circuit boards, power supplies 3-phase induction motor. This section contains brief description individual printed circuit boards (PCB) that comprise system.
WARNING:
motor control system described this application note capable operating dangerous voltages capable supplying high amounts power rotating machines. Power transistors, coil, motor reach temperatures enough cause burns. facilitate safe operation, highvoltage input power power board should come from current-limited laboratory power supply. Before moving test oscilloscope probes, making connections, etc., generally advisable power down high-voltage power supply. When high voltage applied, using only hand operating test setup minimizes possibility electrical shock. Operation laboratory setups that have grounded tables and/or chairs should avoided. Wearing safety glasses, avoiding ties jewelry, using shields also advisable.
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Application Note System Hardware
MR32 Control Board
more detailed description MR32 control board, refer Motorola's Embedded Motion Control Series MR32 Control Board User's Manual (Motorola document order number MEMCMR32CBUM/D) that comes with board (kit #ECCTR908MR32). This document also downloaded from control board designed hardware software design single, 3-phase, permanent magnet, brush brushless motor drive applications.
Freescale Semiconductor, Inc.
control board does contain MR32 microcontroller. control board designed directly connected MR32 (emulator) board, which part MMDS/MMEVS emulation system connected impedance matched ribbon cable. daughter board designed house MR32 will plug into control board place emulator cable. With daughter board plugged into control board, standalone operation system possible. Because this application note intended with 3-phase induction motor, only circuitry resident MR32 control board pertaining 3-phase motor discussed here. Applications control board with other types motors covered additional application notes. Figure shows complete block diagram control board. Control board features include: motor control outputs with indicators Speed control potentiometer Optoisolated half duplex RS-232 interface Start/Stop forward/reverse switches Hall effect inputs (for brushless motor control) Back-EMF inputs (for brushless motor control) Tachometer input configuration jumpers 2-position switch user option control Emulator/Daughter board connectors Processor reset switch system fault inputs Nine analog inputs
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Freescale Semiconductor, Inc. Application Note
Three software-controlled LEDs On-board regulated power supply Motor interface ribbon cable connector
TERMINAL
OPTO-ISOLATED FORWARD/REVERSE RS-232 SWITCH START/STOP SWITCH EMULATOR/ PROCESSOR CONNECTOR CONFIG JUMPERS
SPEED RESET SWITCH OPTION SWITCHES
TACH INPUT HALL EFFECT INPUTS
Freescale Semiconductor, Inc.
POWER 12-15
REGULATED POWER SUPPLY
STATUS LEDS
LEDS
OPTO/POWER DRIVER CONNECTOR OVERCURRENT/ OVERVOLTAGE INPUTS BACK-EMF CURRENT/TEMP INPUTS SENSE INPUTS MISC. OUTPUTS CONTROL
40-PIN CONNECTOR
Figure MC68HC908MR32 Control Board Block Diagram better understanding control board, description some circuits follows.
Fault Inputs
system fault inputs control board designed protect power stage: system overvoltage system overcurrent. input signals these fault comparators originate from signals power board. optoisolation board used system, these signals optocoupled transparently passed control board analog signal. comparator circuits provide digital signals MR32's fault fault inputs, respectively. These faults, should both occur, will force generator into known inactive state, protecting power stage outputs. Figure schematic circuit used both fault inputs. potentiometer, connected inverting input comparator, sets threshold. When input from power board optoisolation board exceeds comparator threshold (voltage inverting input comparator), respective fault input MR32 driven logic triggering fault input generator.
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Application Note System Hardware
Adjusting set-point potentiometer allows user vary acceptable system current voltage thresholds fault generation. Approximately hysteresis included circuit with noise immunity.
I_sense/ V_sense Input +5V_D +5V_A_ref
Freescale Semiconductor, Inc.
OVERVOLTAGE LM339D
GNDA
I_DCB_ref/V_DCB_ref
Figure Fault Generation Circuit Speed Sensing method used establish speed motor analog output signal from tachometer generator that connected shaft motor. 16-pole tachometer coupled shaft motor shown Figure conditioned signal then carried into timer interrupt MR32. period between interrupts used calculate motor shaft speed. circuit Figure used "square" signal from tachometer output into digital signal acceptable timer interrupt input. input this circuit threshold approximately input hysteresis approximately with noise immunity.
+15V_A_ref TACHOMETER INPUT GNDA GNDA MMSZ5230BT1 nF/100 GNDA GNDA
+5V_A_ref
+5V_D
LM339D
TIMER INTERRUPT
Figure Tachometer Input Circuit
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Freescale Semiconductor, Inc. Application Note
Optoisolated RS-232 Interface event control board used system that does optoisolation board between control board power stage, connection computer terminal could dangerous. circuit Figure schematic half-duplex optoisolated RS-232 interface used MR32 control board. This isolated terminal interface provides margin safety between motor control system computer terminal RS-232 specification states signal levels range from 3volts 25volts. mark defined RS-232 specification signal that ranges from volts volts. space defined signal that ranges from volts volts. Therefore, meet RS-232 specification, signals from terminal must transition through volts changes from mark space. Breaking isolated RS-232 circuit into input output sections makes simpler explanation circuit. send data from MR32 control board, necessary satisfy input MR32. idle condition, input must logic accomplish that, transistor must off. idle state transmit data line (TXD) serial port mark Therefore, diode transistor off, yielding logic input. When start sent from PC's serial port, PC's transitions from mark space forward biasing diode Forward biasing diode turns transistor providing logic input SCI. Simply stated, input half circuit provides input isolation, signal inversion, level shifting from MR32's port. RS-232 line receiver, such MC1489, serves same purpose without optoisolation function. send data from MR32 control board serial port input, necessary satisfy PC's receive data (RXD) input requirements. idle condition, input must mark data terminal ready output (DTR) outputs mark when port initialized. request send output space when PC's serial port initialized. Because interface half-duplex, PC's output also mark, idle. idle state transmit data line (TXD) MR32's
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Application Note System Hardware
Freescale Semiconductor, Inc.
logic logic SCI's output port forces diode turned off. With diode turned off, transistor also turned off. junction mark With transistor turned off, input pulled mark through current limiting resistor R53, satisfying PC's serial input idle condition. When start sent from MR32's port output MR32's SCI, output transitions logic That logic turns diode thus turning transistor conducting transistor passes voltage output from PC's output, that space PC's receive data (RXD) input. Capacitor bypass capacitor used "stiffen" mark signal. output half circuit provides output isolation, signal inversion, level shifting from MR32's output port PC's serial port. RS-232 line driver, such MC1488, serves same purpose without optoisolation function.
ISOLATION BARRIER +5V_D
SFH6106
+5V_D
(+12 Vdc)
SFH6106
Figure Optoisolated RS-232 Circuit
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Freescale Semiconductor, Inc. Application Note
Back-EMF Zero-Crossing Detection Back-EMF zero-crossing detection enables position recognition when controlling brushless motors. Sensorless brushless motor control discussed this application note. Rather, refer Sensorless Brushless Motor Using MC68HC908MR32 Embedded Motion Control Development System, Motorola document order number AN1858/D, more information. perform distortion correction when controlling 3-phase induction motor, necessary provide phase current polarity information MR32. That information detected, signal conditioned power board, passed transparently through optoisolator board control board. three zero-crossing signals from phases routed into three input current sense IS1-IS3 inputs MR32. They also routed back-EMF selection logic, shown Figure back-EMF selection logic designed provide interrupt MR32 channel timer upon each phase zerocrossing, provided other input NAND gate logic three open collector NAND gates shown Figure (U7A, U7B, U7C) wire ORed such that these outputs transitioning logic will provide interrupt MR32's timer system software uses MUXA, MUXB, MUXC inputs NAND gates enable particular phase have ability interrupt processor. During system operation, software aware window when particular zero-crossing interrupt should occur given phase. MUXA, MUXB, MUXC inputs NAND gates enabled each particular phase during computed zero cross window. Using this technique, system more noise robust, eliminating noise glitches from triggering false interrupts outside particular "zero cross window."
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Application Note System Hardware
+5V_D
Zero_cross_A
+5V_D MC74HC03AD
Zero_cross_B BEMF_z_c
Freescale Semiconductor, Inc.
MC74HC03AD
MC74HC03AD
Zero_cross_C
MUX_A MUX_B MUX_C
MC74HC03AD
Figure Zero Cross Back-EMF Circuit Optoisolation Board function optoisolation board provide galvanic isolation barrier between control board's I/O, both analog digital, high-voltage system power board's I/O. These isolated signals, from optoisolation board, connected 40-pin ribbon cables. assignments both connectors same. Signal flow through optoisolation board, both directions, one-to-one relation source. more detailed description optoisolation board, refer Motorola's Embedded Motion Control Series Optoisolation Board User's Manual, Motorola document order number MEMCOBUM/D. Figure shows block diagram optoisolation board.
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Freescale Semiconductor, Inc. Application Note
BACK-EMF (ANALOG) ZERO-CROSS (DIGITAL) SERIAL BOARD CONTROL INHIBIT BREAK CONTROL AUX. PHASE CURRENT SENSE TEMP. SENSE CURRENT VOLTAGE PWM(6) POWER 12-15 CONVERTER
SIGNALS CONTROL BOARD
SIGNALS POWER BOARD
Freescale Semiconductor, Inc.
Figure Optoisolation Board Block Diagram Gate Drive Gate drive signals, from control board power stage, passed from controller power stage through high-speed digital optocouplers. Analog feedback signals from power stage controller board passed through HCNR201 high-linearity analog optocouplers. Ground signals between control board power stage separated optocouplers' galvanic isolation barrier. Power requirements control board's circuitry satisfied with single external 12-Vdc power supply. power supply connected optoisolation board control board through 40-pin ribbon cable connector. Excitation power stage side circuitry supplied power stage through 40-pin output connector located optoisolation board. addition usual motor control signals, MC68HC705JJ7 serves serial link, which allows controller board's software identify configuration optoisolation board power stage boards pass configuration information control board processing system configuration checking.
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Application Note System Hardware
Optoisolation Board
optoisolation board number individual circuit blocks. first circuit power supply block, supplying Vdc, +3.3 Vdc, Vdc, board. power circuits comprised individual linear regulators. next circuit digital optoisolation circuit. last circuit linear optoisolation circuit. discussion optoisolation blocks follows.
Freescale Semiconductor, Inc.
Digital Optoisolation Circuit
Figure simplified schematic diagram basic design digital optoisolation circuit used optoisolation board. circuits used couple several control signals from control board power board. Those signals signals, spare bidirectional optoisolation I/O, inhibit, PWM, motor brake control signal from controller board power stage. Also, optoisolation board used couple four digital feedback signals from power board control board. Those signals phases zero cross signals zero cross signal.
+5V_D_PS +5V_D_CB MC74HCT00AD +5V_D_CB ISO1 ANODE GND_CB CATHODE VOut GND_PS HCPL-J454#300 MC74HCT14AD DIGITAL SIGNAL
DIGITAL SIGNAL GND_CB
Figure Digital Optoisolation Circuit digital isolation block based Agilent Technologies' HCPL-J454 high dv/dt coupler. simplified schematic shown Figure When MR32 reset, until been system software, most cases, outputs three-stated. sets logic absence signal. Open input pull down important gate drive signals, where desirable keep power transistors case either broken connection absence power control board until ports have been
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Freescale Semiconductor, Inc. Application Note
Next, NAND gate, U1A, inverts input signal. Assuming logic input (across R1), U1A's output high. With forward bias input diode optocoupler, optocoupler's output transistor off, producing logic high. This logic high inverted produce logic output. Conversely, when input (across high, output low. Forward bias input optocoupler causes light shine optocoupler's photodiode which produces leakage current that flows into optocoupler's base. With base current supplied, optocoupler's transistor optocoupler's output low. That input into causes output high. block whole, therefore, non-inverting.
Freescale Semiconductor, Inc.
Analog Optoisolation Circuit
Figure simplified schematic diagram basic design analog optoisolation circuit used optoisolation board. circuits used couple several feedback signals from power board controller board. Those signals phases current feedback, system current, voltage, heatsink temperature phase back-EMF signals.
ANALOG INPUT (VIn)
MC34072D
ISO1
GNDA_CB ANALOG OUTPUT (VOut)
GNDA_PS
HCNR201#300
MC33502/D
Figure Analog Optoisolation Circuit
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Application Note System Hardware
Freescale Semiconductor, Inc.
analog isolation block based Agilent Technologies' HCNR201 high-linearity optocoupler. HCNR201 consists photodiodes. photodiodes (PD1) input side optoisolation barrier, other photodiode (PD2) output side. package constructed that each photodiode receives approximately same amount light from LED. Feedback amplifier, configured with monitor light output automatically adjust current compensate non-linearity. output photodiode then converts stable, linear light output into current, which then converted back into voltage amplifier Circuit operation immediately obvious from inspecting Figure particularly input part circuit. Stated briefly, amplifier adjusts forward current (IF) such that current (IPD1) equal VIn/R1. Analysis input circuit reveals that increasing input voltage increases voltage inverting input terminal Amplifier amplifies that increase, causing IPD1 increase. Given that connected, IPD1 will pull inverting input op-amp back toward ground. will continue increase until inverting input voltage stabilizes near ground reference voltage. Assuming that current flows into inputs current flowing through will flow through PD1. Since inverting input approximately volts, current through therefore IPD1, equal /R1. Essentially, amplifier adjusts such that IPD1 -VIn/R1. Note that IPD1 depends only input voltage value independent optocoupler's characteristics. Also note that IPD1 directly proportional VIn, giving very linear relationship between input voltage photodiode current. physical construction optocoupler's package determines relative amounts light that fall photodiodes and, therefore, ratio photodiode currents. This results current, IPD2, that very nearly equal IPD1. Amplifier resistor form transresistance amplifier that converts IPD2 back into voltage, VOut, where VOut IPD2 Combining input output equations results expression that relates output voltage input voltage, VOut/VIn (R3/R1). Therefore, with output signal closely matches input.
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Freescale Semiconductor, Inc. Application Note Power Stage
more detailed description 3-phase BLDC high-voltage power stage, refer Motorola Embedded Motion Control Series 3-Phase BLDC High-Voltage Power Stage User's Manual, Motorola document order number MEMC3PBLDCPSUM/D. function power stage provide high-power drive circuitry various types motors. power stage suitable driving induction, permanent magnet, brush brushless motors. power stage consists printed circuit boards (PCB). PCBs power module, containing power IGBTs (insulated gate bipolar transistors), brake IGBT, power factor corrector (field-effect transistor), temperature-sensing diodes. second contains IGBT drive circuits, analog signal conditioning, lowvoltage power supplies, power factor control circuitry, MC68HC705JJ7 microcontroller used board configuration identification. Figure shows complete block diagram power module. Power module features include: 1-phase bridge rectifier Power factor switch diode dc-bus brake IGBT brake current limiting resistors 3-phase bridge inverter (six IGBTs) Individual phase current sensing shunt resistors with Kelvin connections Power stage temperature sensing diodes IGBT gate drivers Current temperature signal conditioning 3-phase back-EMF voltage sensing zero cross detection circuitry Board identification processor (MC68HC705JJ7) Low-voltage on-board power supplies Cooling fans
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Application Note Power Stage
POWER INPUT
SWITCH MODE POWER SUPPLY
CONTROL BRAKE
SIGNALS TO/FROM CONTROL BOARD
IGBT POWER MODULE GATE DRIVERS PHASE CURRENT PHASE VOLTAGE CURRENT VOLTAGE MONITOR BOARD BLOCK ZERO CROSS BACK-EMF SENSE 3-PHASE MOTOR
Freescale Semiconductor, Inc.
Figure Power Module Block Diagram better understanding power stage, description several circuits follows. Power Switch Driver Circuitry Figure schematic diagram basic design power switch driver circuitry. IGBT drivers, IR2112S, provide control power IGBT power switches shifting transforming logic level control signals levels necessary control power switches. turn-on time IGBT power switch controlled resistors R401 R402 which connected power switch gates. Diodes D402 D404 fast turn IGBT power switches providing low-impedance path back IR2112S discharge power switch's gate. D401 protects power supply other circuits connected preventing high voltage that could flow power input (pin IR2112S. overcurrent situation should occur, overcurrent circuit power module will supply shut down signal IR2112S, turning outputs, thus protecting power switches. input, pull down resistors, R403 R404, logic absence signal. Open input pull down important gate drive signals, where desirable keep power transistors case either broken connection absence power control board.
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Freescale Semiconductor, Inc. Application Note
D402 MBRS130LT3 Gate_AT
R401 U404A DM74ALS1034M PWM_AT C401 C419 R403 R404 C420 U404B DM74ALS1034M +5V_D R414 Shut_Down R413 C402 µF/16V +5V_D U401 IR2112S D401 MURS160T3 +15V_D D403 MMSZ5251BT1 D404 MBRS130LT3 C404 C416
C403
Source_AT
PWM_AB
R402
Gate_AB
Freescale Semiconductor, Inc.
C413 +5V_D
D405 MMSZ5251BT1
Source_AB
Figure IGBT Driver Circuit
Signal Conditioning
Phase currents measured sensing voltage drop across sensing shunt resistors located power module. Figure schematic diagram design analog signal conditioning circuit. output voltage amplifier proportional sensed currents. input circuit Figure derived across 0.075- shunt resistor connected series with particular current being measured. input signal amplifier multiplied times then output amplifier shifted 1.65-volt reference. final output circuit ±1.65 volts with input current ±2.93 amps passing through 0.075- shunt resistor.
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Application Note Power Stage
75.0 10.0 I_sense_A2 10.0 +3.3V_A
I_sense_A1
I_sense_A MC33502D
75.0 1.65
LM285M
33.2
Freescale Semiconductor, Inc.
GNDA GNDA
Figure Current Sensing Circuit Overcurrent Detection Excessive current destroy power transistors power stage. Including overcurrent protection circuitry design wise choice, absolute necessity. Figure schematic overcurrent detection circuit. input signal this circuit 0.075- resistor, placed series with amplified same type circuit shown Figure output this circuit shown Figure drives shut down input IR2112S's IGBT drivers. Whenever overall current exceeds ±2.82 amperes, IR2112S's outputs disabled. Excessive current destroy power transistors power stage.
I_sense_DCB +15V_D
CAUTION:
+3.3V_A OVERCURRENT THRESHOLD= 3.23
LM393
GNDA
Figure Overcurrent Detection Circuit
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Shut_Down_Open_C.
Freescale Semiconductor, Inc. Application Note
Temperature Sensing good idea keep track temperature power module. circuit shown Figure schematic temperature circuit used monitor temperature. silicon diode temperature coefficient approximately -2.2 /degree Centigrade. forward bias voltage silicon diode approximately volts. Therefore, circuit shown Figure will output approximately volts 25°C decrease slope approximately -8.8 mV/degree Centigrade. Using this information, apparent that temperature power module monitored easily over- temperature conditions. output this temperature sensing circuit connected analog optoisolation circuit. From analog optoisolation circuit's output, connected control board's Temp_sense input routed MR32's (analog-to-digital) converter input.
+3.3V_A
Freescale Semiconductor, Inc.
R302 2.21
Temp_sense BAV99LT1 BAV99LT1 C301 GNDA TEMPERATURE SENSING
Figure Temperature Sensing Circuit Schematic
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Application Note Power Stage
Brake
Freescale Semiconductor, Inc.
Under certain operating conditions, motor generator, delivering high voltage back into through inverter's power switches and/or power switch source-drain recovery diodes. That very undesirable condition damage power transistors other components inverter. excess energy must dissipated; otherwise, voltage will rise above safe limit. power module contains IGBT current limiting resistors, placed across brake dissipate excess energy. Figure schematic brake control circuitry. When using brake, care must taken exceed power dissipation brake transistor current limit resistors. Provisions made power board user install additional brake resistor across composed R6-R9, allowing additional brake current imposed system. Again, care must taken exceed ratings IGBT brake transistor when additional brake resistor installed system. Typically, system software will pulse-width modulate brake dissipate excess voltage until brought down acceptable level. Under certain operating conditions, motor generator, delivering high voltage back into through inverter's power switches and/or power switch source-drain recovery diodes. This damage power transistors other components inverter.
+15V_D
CAUTION:
C202 µF/35 C203 Brake_Res SGB04N60 D201 MMSZ5251BT1
DCB_Cap_Pos
HFA04TB60S
U202 Brake_control R202 C212
OutA
OutB
R204
MC33152D
DCB_Cap_Neg
Figure Brake Circuit Schematic
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Freescale Semiconductor, Inc. Application Note
Voltage Divider system software monitors number analog parameters when motor running. Those parameters include system voltage three individual phase voltages. four cases, high voltage divided down level within measurable range MR32's converter. Figure schematic voltage divider used monitoring voltage. signal labeled V_sense_DCB_5 divided down voltage that MR32 either directly optoisolator board when utilized system. signal labeled V_sense_DCB_half_15 used reference individual phases zero cross detection circuits.
k-1% R225 DCB_Cap_pos C213 nF/3000 Earth_GND C214 nF/3000 DCB_Cap_neg GNDA C208 k-1% R224 4.87 k-1% R226 R228 6.81k-1% R229 R230 6.81 k-1% k-1% R227
Freescale Semiconductor, Inc.
C209 µF/400
Figure Voltage Sensing Circuit
Individual Phase Voltage Divider
similar fashion sensing circuit shown Figure individual phase voltages divided down match input level A/D. Figure shows schematic voltage divider phase There additional circuits voltage monitoring zero cross detection phases This technique allows sensing back-EMF from motor. individual phase voltage signals separate inputs microcontroller either directly optoisolator board utilized system. signal shown labeled BEMF_sense_A (BEMF_sense_B BEMF_sense_C, depending particular phase signal). additional function circuit shown Figure detect zerocrossing phases Note that inverting input
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Application Note Power Stage
comparator reference from divider (V_sense_DCB_half_15). Using divider reference, when phase phase voltages reach percent signal, corresponding phase zero cross point, output comparator will transition from logic logic That transition used distortion correction information IS1-IS3 inputs generator input zero cross widow logic zero cross interrupt generation.
Freescale Semiconductor, Inc.
case induction motor, this zero cross circuit provides phase current polarity signals needed inputs dead-time compensation algorithm.
Phase_A R501 k-1% R502 k-1%
R504 k-1%
R506
R505
R507 21.0 k-1% BEMF_sense_A R508 6.81 k-1% GNDA
U501C LM339D
Zero_cros_A
V_sense_DCB_half_15 C505 GNDA
Figure Back-EMF Zero Cross Detection Schematic
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Freescale Semiconductor, Inc. Application Note
Power Factor Correction Power factor correction control (PFC) circuitry provides control switch handles necessary feedback provide sinusoidal power line current. capability enabled disabled changing jumper configuration power module. jumper found proximity capacitor. objective hardware software draw sinusoidal current from main supply power attempt approach close possible unity power factor. circuitry power board boost power supply, controlled MR32 control board. Without PFC, current from main supply tends draw current peak sine wave. Describing control circuity exceeds scope this application note. forthcoming application note will describe control detail.
Freescale Semiconductor, Inc.
3-Phase Motor Control System Configuration
Figure block diagram complete 3-phase motor control system configuration with MMDS05/08 emulation system workstation. optional connected MR32 control board, shown. optional used communicate control system parameters system software running control board. system exercised standalone mode, without MMDS05/08 emulator workstation, placing programmed MR32 into daughter board plugging into control board place MMDS05/08 emulator system.
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Application Note Software
MMDS08 EMULATION SYSTEM WITH MR32EM BOARD WORKSTATION*
system without workstation emulator using programmed MR32 daughter board, plugged into MR32 controller board.
Freescale Semiconductor, Inc.
40-PIN RIBBON 68HC908MR32 CONTROLLER BOARD OPTOISOLATION BOARD
40-PIN RIBBON HIGH-VOLTAGE POWER BOARD
TACHOMETER
3-PHASE INDUCTION MOTOR OPTIONAL TERMINAL LOW-VOLTAGE POWER SUPPLY HIGH-VOLTAGE POWER SUPPLY
Figure 3-Phase Motor Control System Block Diagram
Software
software written system controls 3-phase induction motor. system software includes power factor correction software PC-Master communication capability. Using potentiometer located control board motor's speed setting, tachometer feedback scheme used close speed control loop, using loop control algorithm. Basic features control software are:
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Controlled acceleration deceleration Speed range 3000 Drive clockwise counterclockwise. Speed sensed tachometer/generator frequency voltage protected brake
Freescale Semiconductor, Inc. Application Note
Features PC-Master communication software include: Ability read/write (random-access memory) variable Read (read-only memory) variable Execute PC-Master commands
Features power factor correction software include: Automatic calibration control loop Automatic input voltage detection V/60 V/50
Freescale Semiconductor, Inc.
Software Design
This section describes design functionality system software that executes MMDS05/08 emulator system programmed MR32, resident daughter board, plugged into control board. PC-Master communication software intended used developing motor control software. required actions motor control software manipulated operator when using PC-Master software. PC-Master software executes that connected isolated RS-232 serial port control board. PC-Master software executing uses Microsoft Internet Explorer user interface small program resident MR32 that communicates with PCMaster software parse commands, return status information process control information from actions controlled PC-Master are: Start/Stop control Motor speed setpoint Reset drive system Motor rotation direction control (CW/CCW)
PC-Master
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Application Note Software
Variables read PC-Master software default displayed user are: Required speed Actual motor speed voltage Power module temperature Display system status error flags
Freescale Semiconductor, Inc.
latest information regarding PC-Master software, refer Motorola, Semiconductor Products Sector, Motor Control page: latest application note software, refer following links: System Software motor drive controlled ways. manual operation mode, speed potentiometer, start/stop forward/reverse controls mounted control board. PC-Master mode operation, motor drive control performed from commands from connected control board.
motor control software monitors state sensors they periodically scanned software timer loop, while speed motor calculated utilizing input capture interrupt. Whenever motor running, green located control board will illuminate. According operational mode setup state control signals (start/stop switch, forward/reverse switch, speed potentiometer), speed command calculated using acceleration/deceleration ramp. comparison between actual speed command tachometer speed generates speed error. speed error passed speed controller generating corrected motor frequency. Using V/Hz ramp, corresponding
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Freescale Semiconductor, Inc. Application Note
voltage calculated. generation process calculates system 3-phase voltages required amplitude frequency that includes dead-time. 3-phase motor control signals then output power stage. voltage current measured during control process. They used overvoltage overcurrent protection drive. overvoltage protection performed software while overcurrent fault signal utilizes fault input microcontroller.
Freescale Semiconductor, Inc.
aforementioned faults occur, motor control outputs disabled protect drive. system fault state also displayed. These faults, depending operating mode system, output LEDs controller and/or terminal connected control board. design system requires system software take some values from user interface sensors, processes them, generates 3-phase signals motor control. control algorithm close loop drive described Figure consists processes described following subsections. Special attention given subroutine's 3-phase calculation volts hertz control algorithm. Also, initialization microcontroller described.
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Application Note Software
Switches Start/Stop Forward/Reverse Operation Mode Jumper
converters
PROCESS SPEED COMMAND
PROCESS CONTROL
DC_bus_volt
V_command
Tacho
Freescale Semiconductor, Inc.
PROCESS ACCELERATION/DECELERATION RAMP PROCESS SPEED SENSOR Gf_flag V_com_actual V_tacho PROCESS CONTROLLER
PROCESS FAULT CONTROL
V_pi_out PCTL1 PROCESS V/Hz RAMP
Fault
Amplitude
Table_inc
PROCESS GENERATION
PVAL1
PVAL3
PVAL5
Figure Data Flow
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Freescale Semiconductor, Inc. Application Note
When MR32 reset, software configures various system I/O. forward/reverse switch, start/stop switch, voltage checked, speed potentiometer's value input. yellow located control board illuminated when system ready. identification connected boards (optoisolator power boards) checked. default operation mode manual. PC-Master operation mode PC-Master command. algorithm initialized. After initialization passed, fault flag (failure) tested system faults. Anytime fault detected system, located control board will illuminate. system name voltage Out_volt_new. value input from speed labeled Pot_voltage. input parameters process evaluated speed command V_command calculated accordingly. Also, voltage, named dc_bus_volt, measured. general fault Gf_flag analyzed state drive set. drive state diagram shown Figure status LEDs controlled according system state. calculated speed command V_command 2-byte variable with format 0x0100). upper byte represents integer portion lower byte represents fractional portion value. This format kept through program speed variables. system software calculates speed based requested speed, according acceleration/deceleration ramp.
Freescale Semiconductor, Inc.
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Application Note Software
Reset
Stand-By State V_command Start/Stop disabled
General Fault Recovery
Fault Recovery State State Start/Stop V_command disabled General Fault enabled Fault State Start/Stop V_command disabled Stop State disabled Over Voltage Over Current
Freescale Semiconductor, Inc.
V_command v_pi_out
Figure Drive State Diagram During deceleration, motor work generator. generator state, capacitor charged voltage easily exceed maximum voltage. Therefore, voltage measured compared with limit. case deceleration overvoltage, deceleration interrupted motor runs with constant speed discharge capacitor down acceptable limit. Deceleration then continue. During deceleration, depending input line voltage, algorithm either turned voltage controlled reduced volts. speed sensor process utilizes MR32's input capture interrupt function. circuit Figure signal conditions motor's tachogenerator output. input capture interrupt reads time between rising edges speed sensor's output calculates actual motor speed V_tacho. software filter speed measurement incorporated process better noise immunity. this case, actual motor speed calculated average value several measurements.
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Freescale Semiconductor, Inc. Application Note
general principle behind control loop shown Figure speed closed-loop control characterized measurement actual motor speed. This information compared with reference point, error signal generated. magnitude polarity error signal corresponds difference between actual required speed. Based speed error, controller generates corrected motor frequency compensate error accomplish required motor speed.
Freescale Semiconductor, Inc.
This process takes input parameters: actual speed command V_com_actual actual motor speed measured tachogenerator V_tacho. controller then calculates speed error performs speed control algorithm. output controller frequency fundamental sine wave generated inverter, V_out.
CORRECTED SPEED (V_pi_out) CONTROLLER
REFERENCE SPEED (V_com_actual)
SPEED ERROR
CONTROLLED SYSTEM
ACTUAL MOTOR SPEED (V_tacho)
Figure Closed Loop Control drive designed constant volts-per-hertz drive. This means control algorithm keeps magnetizing current (flux) motor constant varying stator voltage with frequency. ratio voltage divided frequency constant during linear portion profile. commonly used volts-per hertz profile 3-phase induction motor illustrated Figure
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Application Note Software
PHASE VOLTAGE 100% BASE POINT
BOOST VOLTAGE
Freescale Semiconductor, Inc.
BOOST FREQUENCY
BASE FREQUENCY
FREQUENCY (rpm)
Figure Volts-per-Hertz Ramp volts-per-hertz profile defined these parameters: Base point Defined base frequency (usually Boost Defined boost voltage boost frequency
ramp profile fits specific motor easily changed accommodate different ones. This software function, RAMP.C, provides voltage calculation according V/Hz ramp. input this software function generated inverter frequency V_out. Parameters required generation process output this software function: Table increment Table_inc that corresponds frequency V_out used roll through wave table generate output inverter frequency Amplitude generated inverter voltage
process sine wave generation provides 3-phase sine waves, each shifted degrees relative each other. sine waves pure sine waves they include third harmonic component.
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Freescale Semiconductor, Inc. Application Note
calculation based wave table stored MCU's ROM. table describes either pure sine wave sine wave with third harmonic added. second case often preferred because allows generation first harmonic sine voltage equal input line voltage. Because quarter wave symmetry, only quadrant wave period stored table. wave values other quadrants calculated from first one. format stored wave table data from 0x00 (for voltage) modulus/2 (for percent voltage). Thus, proper data scaling secured.
Freescale Semiconductor, Inc.
NOTE:
important note that percent percent modulus loaded corresponding PVAL registers) corresponds zero phase voltage. wave table, ZERO phase voltage corresponds number 0x00. Therefore, fetched wave value from table must added percent modulation quadrants subtracted from percent modulation quadrants (see point process description that follows). Thus, correct value loaded. input parameters PWMCALC.C are: Table increment Table_inc that used wave pointer update Amplitude generated inverter voltage
output parameters process are: value phase PVAL1 register value phase PVAL3 register value phase PVAL5 register
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Application Note Software
process described following these points: Phase Wave pointer phase updated TableIncrement. Based wave pointer, required wave quadrant selected. quadrant pointer calculated from wave pointer with respect related quadrant. table value determined quadrant pointer fetched from wave table.
Freescale Semiconductor, Inc.
table value added subtracted from) percent modulus with respect related quadrant. result loaded PVAL1 register; PVAL2 register loaded automatically because complementary mode selected during module initialization. Phase phase wave pointer calculated phase wave pointer +1/3 wave period (1/3 0xffff equals 0x5555), which equivalent degrees. corresponding points phase calculation steps through result loaded PVAL3 register; PVAL4 register loaded automatically because complementary mode. Phase phase wave pointer calculated phase wave pointer +2/3 wave period (1/3 0xffff equals 0xaaaa), which equivalent degrees. corresponding points phase calculation steps through result loaded PVAL5 register; PVAL6 register loaded automatically because complementary mode. process accessed regularly rate given frequency selected interrupt prescaler (register PCTL2). This process repeated often enough compared wave frequency generate correct wave shape. Therefore, 16-kHz frequency, called every fourth pulse thus registers updated 4-kHz rate (250 µs).
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Freescale Semiconductor, Inc. Application Note
event system fault, important note that software services event timely manner. software accommodates fault inputs, overcurrent overvoltage. Overcurrent case overcurrent, external hardware provides rising edge fault input microcontroller's FAULT2 input through circuit described Figure This signal disables motor control PWM's outputs (PWM1 through PWM6) sets general fault flag Gf_flag. Over_current_flag failure register used PC-Master control interface.
Freescale Semiconductor, Inc.
Overvoltage sensed dc-bus voltage compared with limit within software. case overvoltage, motor control outputs disabled software setting bits microcontroller's control register (PCTL1) setting general fault flag Gf_flag. Over_voltage_flag failure register used PC-Master control interface. overvoltage fault only motor braking generator mode). motor mode (the motor supplies power load), overvoltage occurs, disabled; overvoltage failure detected motor blocked. should noted that output voltage operates very close volts, which overvoltage limit. regulation overshoot would cause overvoltage failure when running. Therefore, overvoltage blocked when running. these faults occur, fault will flash. system remains disabled until fault cleared switching START/STOP switch STOP position then START position fault cleared PC-Master setting ERROR_CLEAR_PMFLG Motor_Ctrl control register. After switch START/STOP START, motor will restart. processes described earlier implemented single state machine illustrated Figure Figure Figure general state diagram incorporates main routine entered from reset eight interrupt states. main routine includes initialization microcontroller software timer control algorithm timebase. interrupt states provide calculation speed motor, overcurrent fault handler, generation process, zeroAN1857 More Information This Product, www.freescale.com MOTOROLA
Application Note Software
crossing interrupt PFC, output compare generate input current waveform, interrupt control output voltage, read, transmit routines. Initialization main routine provides initialization microcontroller: Clears Initializes clock Initializes module: Center-aligned complementary mode, positive polarity (MOR register) enable (MOR register) modulus Defines frequency (PMOD register) 2-µs dead-time (DEADregister) interrupt reload every fourth cycle (PCTL2 register) FAULT2 (overcurrent fault) manual mode, interrupt enabled (FCR register) Sets ports Initializes timer input compare, output compare, software timer reference Initializes timer generation Initializes converter Detects connected boards Detects input line voltage limits Detects input line frequency Calibrates feedback offset FB_offset error occurs, fault turned failure register set, software waits reset. Enable interrupts
Freescale Semiconductor, Inc.
example initialization clock motor control modules MR32 follows.
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Freescale Semiconductor, Inc. Application Note
setup clock PBWC 0x80; while (~PBWC 0x40); PCTL 0x30; Auto Bandwidth Control wait lock clock
setup Motor Control module 0x00; pos. center mode; enabled (0x60: neg. center mode; enabled) PMOD =PWM_MODULUS; modulus frequency /*7.3728MHz Frequency PWM_MODULUS 0x00e6 gives16kHz DEADTM=15; 2usec deadtime (for freq. 7.3728MHz) DISMAP=0xff; when disabled, disable PWM1-6 PCTL2 0x80; interrupt every 4th. loads PCTL1 0xc0; disable MCPWM PWMOUT 0x00; output port control generator PCTL1 0x02; LDOK 0x08; Flt2 enabled manual mode PVAL1 PWM_MODULUS/2; phase PVAL3 PWM_MODULUS/2; phase PVAL5 PWM_MODULUS/2; phase
Freescale Semiconductor, Inc.
When modules microcontroller initialized, code will then enable module like this:
PCTL1 0x20; PCTL1 0x01; enables interrupts enables
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Application Note Software
software timer routine provides timing sequence required subroutines. software timer performed instead output compare interrupt handler. main program several time-demanding interrupt routines, more interrupt requirements cause software fault. software timer routine timed outputs: READ_CONST routine that scans inputs, calculates speed command, handles fault routines, driver.
Freescale Semiconductor, Inc.
PI_CONST routine that provides overvoltage protection during deceleration, speed ramp (acceleration/deceleration), controller, V/Hz ramp, provides parameters generation. interrupt handlers have these functions: input capture interrupt handler reads time between subsequent input capture edges (basic part process speed sensor). fault interrupt handler takes care overcurrent fault interrupt (overcurrent part process fault control). interrupt handler generates system 3-phase voltages motor (process generation). input capture interrupt handler channel timer performs synchronization PFC. Output compare interrupt handler generates waveform input current. interrupt handler performs control output voltage. read interrupt handler services receive interrupts PC-Master communication routines. transmit interrupt handler services transmit interrupts PC-Master communication routines.
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Freescale Semiconductor, Inc. Application Note
Reset
Input Capture Interrupt
Interrupt Handler done Initialize Software
done Fault Interrupt
Freescale Semiconductor, Inc.
timeout Fault Interrupt Handler Software Timer done done timeout done
timeout
READ_CONST
Interrupt
Interrupt Handler
PI_CONST
done
Figure State Diagram General Overview
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Application Note Software
READ_CONST accessed from main software timer READ_CONST rate. following sequence performed. Figure READ_CONST: inputs scanned (speed pot, start/stop switch, forward/reverse switch, temperature, current). voltage measure interrupt routine. speed command calculated according operational mode. voltage compared with overvoltage limit overcurrent flag checked. case fault condition, fault recovery routine entered until recovery time expires; drive remains disabled. Finally, driver controls individual LEDs according status drive. hardware enabled/disabled according drive status. PC-Master commands serviced.
Freescale Semiconductor, Inc.
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Freescale Semiconductor, Inc. Application Note
READ_CONST Timeout
Scan Inputs
done
Operational Mode Distribution
Freescale Semiconductor, Inc.
done
done
Speed Calculation Manual
Speed Calculation Demo
Fault Detection done
Enable Fault Recovery done Fault Recovery done
Driver
Return scheduler
Figure State Diagram READ_CONST
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Application Note Software
PI_CONST accessed from main software timer PI_CONST rate. rate defines time constant controller. following sequence performed (see Figure 26): During deceleration, dc-bus voltage checked, and, case overvoltage, deceleration interrupted until capacitor discharged. When deceleration overvoltage measured, acceleration/deceleration speed profile calculated.
Freescale Semiconductor, Inc.
actual motor speed calculated. based time measurement between subsequent rising edges input capture. speed controller performed corrected motor frequency calculated. corresponding voltage amplitude calculated according voltper-hertz profile. Thus, both parameters generation available (Table_inc, Amplitude).
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Freescale Semiconductor, Inc. Application Note
PI_CONST Timeout
Deceleration Overvoltage Protection Overvoltage Overvoltage
Acceleration/Deceleration
Freescale Semiconductor, Inc.
done
Tacho Speed Calculation done
Speed Controller
done
V/Hz Ramp done Return Scheduler
Figure State Diagram PI_CONST Timeout
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Application Note Software
Software Files
software consists following parts: MAIN.C MAIN.C entry point following reset after initial startup code. contains initialization software state code, main state machine with software timer state code. SPEED.C SPEED.C contains READ_CONST code (scan inputs state; operational mode distribution state; speed calculation, manual operational mode state, speed calculation; PC-Master operation mode state; fault detection state; enable state; fault recovery state; driver state; enable/disable logic). RAMP.C RAMP.C contains code acceleration deceleration rampstate, V/Hz ramp state. PI.C PI.C contains PI_CONST timeout code (deceleration overvoltage protection state, tacho speed calculation state, speed controller state, calls acceleration/deceleration ramp state V/Hz ramp state appropriately). FAULT.C FAULT.C contains fault interrupt service routine. PWMCALC.C PWMCALC.C contains code service interrupts which ultimately generate sine outputs power stage. TACHO.C TACHO.C contains timer channel interrupt code that calculates time between tachometer interrupts. MR_IDENT.C MR_IDENT.C contains code that communicates with MC68HC705JJ7 microcontrollers, resident optoisolation power boards. resulting information from this routine used configuration checking input system time parameters. DigitPFC.C DigitPFC.C contains software used drive power factor correction hardware resident power board. software sets duty cycle timer channel that pulse-width modulates power board's input hardware kHz. RAM.C file RAM.C contains global variable definitions system's MR32 software.
Freescale Semiconductor, Inc.
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Freescale Semiconductor, Inc. Application Note
Code_ISR.C CODE_ISR.C contains interrupt reset vector addresses system's MR32 software. SCI.C SCI.C contains PC-Master communication routines code. RAM.H header file RAM.H contains global variable declarations system's MR32 software. CONST.H header file CONST.H contains global system constants definitions system's MR32 software. CODE_FUN.H header file Code_fun.H contains prototypes external functions. 3RDHQUAD.H header file 3RDQUAD.H contains 256-word one-quadrant sine table with third harmonic injection. SCI.H SCI.H contains PC-Master communication constant variables declarations. MR24_VHz_PFC.prm parameter file MR24_VHz_PFC.prm contains interrupt reset vector addresses system's MR32 software.
Freescale Semiconductor, Inc.
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Application Note Conclusion
Conclusion
This application note describes design 3-phase speedcontrolled induction motor with power factor correction optional PC-Master communication software. controller, optoisolation, power boards used this design part Motorola's tool purchased from Motorola. tool enables MR32 evaluated system without necessity building prototype hardware.
Freescale Semiconductor, Inc.
design described this application note illustrates efficiency simplicity using MR32 microcontroller processing heart robust motor control system low-cost industrial consumer motor control applications.
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Freescale Semiconductor, Inc. Application Note
Freescale Semiconductor, Inc.
Motorola reserves right make changes without further notice products herein. Motorola makes warranty, representation guarantee regarding suitability products particular purpose, does Motorola assume liability arising application product circuit, specifically disclaims liability, including without limitation consequential incidental damages. "Typical" parameters which provided Motorola data sheets and/or specifications vary different applications actual performance vary over time. operating parameters, including "Typicals" must validated each customer application customer's technical experts. Motorola does convey license under patent rights rights others. Motorola products designed, intended, authorized components systems intended surgical implant into body, other applications intended support sustain life, other application which failure Motorola product could create situation where personal injury death occur. Should Buyer purchase Motorola products such unintended unauthorized application, Buyer shall indemnify hold Motorola officers, employees, subsidiaries, affiliates, distributors harmless against claims, costs, damages, expenses, reasonable attorney fees arising directly indirectly, claim personal injury death associated with such unintended unauthorized use, even such claim alleges that Motorola negligent regarding design manufacture part. Motorola registered trademarks Motorola, Inc. Motorola, Inc. Equal Opportunity/Affirmative Action Employer.
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USA/EUROPE/Locations Listed: Motorola Literature Distribution; P.O. 5405, Denver, Colorado 80217. 1-303-675-2140 1-800-441-2447 JAPAN: Motorola Japan Ltd.; SPS, Technical Information Center, 3-20-1, Minami-Azabu, Minato-ku, Tokyo 106-8573 Japan. 81-3-3440-3569 ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; Silicon Harbour Centre, King Street, Industrial Estate, N.T., Hong Kong. 852-26668334 Technical Information Center: 1-800-521-6274 HOME PAGE:
Motorola, Inc., 2000
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