Transcript No Slide Title - Kane Computing Ltd

Don’t Compromise:
DSP Controllers Solve Your
Embedded Control Design
Challenges
Presentation begins live from Dallas
October 31, 7:00 a.m. and 11:00 a.m.
Central Standard Time (CST)
C2000, C24x, C28x, F28x, Code Composer, and eXpressDSP are
trademarks of Texas Instruments Incorporated.
eZdsp is a trademark of Spectrum Digital.
Don’t Compromise:
DSP Controllers Solve
Your Embedded
Control Design
Challenges
C2000, C24x, C28x, F28x, Code Composer, and eXpressDSP are
trademarks of Texas Instruments Incorporated.
eZdsp is a trademark of Spectrum Digital.
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Copyright © 2001 Texas Instruments. All rights reserved.
Agenda
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
A quick look at a typical control system
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Challenges and constraints faced by the embedded
control designer
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The ideal solution: Achieving the goal without
compromise
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The advantages of DSP in control applications
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System examples
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Question and Answer session
The Four Major Components of a
Typical Control System
Controller
Analog
or
Digital
Actuator
Plant
Sensor
Examples of control applications
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Thermo-electric coolers (TEC)
Printers/Copiers
Handheld power tools
Motor drives
Fuel pumps
Electronic power steering (EPS)
Uninterruptible power supplies (UPS)
Intelligent sensors
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DVD players
Industrial automation
HVAC compressors
Electronic cooling systems
Fluorescent light ballasts
Toys (e.g. model trains, dolls)
Refrigeration
HVAC blowers
Digital Control Advantages
Outweigh Analog
Analog Controller
+
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High bandwidth
High resolution
Easy to understand/use
“Relatively” low cost
Digital Controller
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Component drift and
aging/unstable
Hardwired/not flexible
Limited to classical
control theory only
Large parts count for
complex systems
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Insensitive to environment (temp, drift…)
High reliability
Software programmable/flexible solution
Precise/predictable behavior
Advanced control possible (non-linear,
multi-variable)
Can perform multiple loops and “other”
functions
Bandwidth limitations (sampling loop)
Numerical problems (quantization,
rounding…)
AD/DA boundary (resolution, speed,
cost)
CPU performance limitations
System cost
?
Today’s DSPs Solve Embedded
Control Design Concerns
Industry Concerns (-)
Bandwidth limitations
(sampling loop)
 CPU performance limitations
Today’s DSP Controllers (+)
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Numerical problems
(quantization, rounding…)
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AD/DA boundary
(resolution, speed, cost)
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System cost
40- and 150-MIPS DSP
16- and 32-bit math
10-/12-bit high-speed ADCs
High-speed/high-resolution
PWMs
Increased on-chip integration
The “No Compromise” Topology!
DAC
DSP
ADC
0110101100
1011011101
0010100111
“Digital/Real World”
Boundary
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“Plant”
“Processing
Engine”
Continually
Improving
specs!
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“DAC”
DSP
DAC
“ADC”
Empowering the Digital Domain
ADC
AD/DA Boundary
Resolution
 Linearity/Accuracy
 Sampling rate (speed)
 HV isolation
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Outputs
 Power inverter
 Solenoids
 Actuators
 Switchers
Inputs
 Current
 Voltage
 Position
 Speed
 Temperature
 Pressure
DSP Controllers – Trends
Cost
($US)
E14
(1989)
F240
$20
F281x
(1995)
(2001/2)
$13
High
MIPS
LF2403
C242
$6-8
(2001)
(1995)
$5
Low
Cost
LC2401
(2001)
$2-3
Performance
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8
20
PWMs  ADC
CAP
(10
I/Os
bits/6mS/0.8mS)
UART  PWMs (50nS)
 CAP/QEP
 I/Os
 UART/SPI/CAN
Peripheral Integration
40
 ADC
(10 bits/400nS)
 PWMs (25nS)
 CAP/QEP
 I/Os
 UART/SPI/CA
N
150
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400 (MIPS)
ADC (12 bits/60nS)
PWMs (6.7nS)
CAP/QEP
I/Os
UART/SPI/CAN/McBSP
Pulse Width Modulation (PWM) –
The “Power DAC”
+ DC_BUS
“The Power DAC”
Inverter
PWM1
PWM
PWM2
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PWM Effective Resolution (# Bits)
PWM
(KHz)
10
20
30
50
System Clock (MHz)
20
30
40
150
11.0 11.6 12.0 13.9
10.0 10.6 11.0 12.9
9.4 10.0 10.4 12.3
8.6
9.2
9.6 11.6
PWM is the only real technique to control high-powered
“actuators.”
“DA” resolution is dependent only on digital clocking speed.
Power switching elements (MOSFETs, IGBTs, Triacs)
continuously improving in frequency, switching losses, high
voltage, and current capabilities.
Switching frequencies above the audible range now very easy
to achieve.
The Classical A/D Converter
PWM1
“The Classical A/D Converter”
Volts
PWM2
ADC
Va
ADC_IN
Signal
conditioning
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10
10-bit resolution
2 Msamples/sec
16 analog channels
16-state
autosequencer
16-deep result
buffer
Ia
F28xx DSP
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12-bit resolution
16.7 Msamples/sec
16 analog channels
Dual sample & hold
16-state
autosequencer
16-deep result
buffer
ADC
F/C24xx DSP
Current
Capture – The “ Time ADC”
t1
Speed Meas. - Effective # Bits
t
“The  Time ADC”
t2
Capture
Sensor
Speed
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Speed
(RPM)
500
1000
2000
5000
System Clock (MHz)
20
30
40
160
16.6 17.1 17.6 19.6
15.6 16.1 16.6 18.6
14.6 15.1 15.6 17.6
13.2 13.8 14.2 16.2
CAPx
Ideal A/D interface to rotating/moving machines or
mechanisms
Time-based measurement ideal way to digitize
period, speed, acceleration
Measurement resolution is dependent only on
digital clocking speed (i.e. time base)
Quadrature Encoder Pulse (QEP) –
The “Position ADC”
Position Meas. - Effective # Bits
“The Position ADC” Index
4 3 21
1000
QEP
q
Position
w
QEPx
Example: 1000 QEP pulses = 360°
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12
Encoder
(# Lines)
500
1000
2000
4000
Position
(# bits)
11.0
12.0
13.0
14.0
A
B
Counter
clock
Ideal A/D interface to rotating/moving machines or
mechanisms
Quadrature encoder ideal way to digitize position,
period, speed, acceleration
MIPS Drive “Mathematical Freedom!”
Control Algorithm Examples
Space vector modulation (SVM)
 Field-oriented (vector) control (FOC)
 Sensorless flux vector position estimation
 Sensorless speed estimation
 Extended Kalman estimator (EKF)
 Sliding mode observer (SMO)
 Model Reference Adaptive System (MRAS)
 Non-linear control techniques
 Online motor parameter self tuning
 Precision PID (32-bit) control
 FFT/FIR/IIR/Matrix functions
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DAC
ADC
MIPS Drive “Friendly Modular Software!”
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FIR
Filter
Sine
Gen
Space
Vec Mod
FFT
128/256
Math
Func
Sliding
Mode
Observer
Math
Func
PID
Control
Flux
Estimator
Foundation Software Libraries for the
General Market
Math Functions
 Sine/Cosine/ArcTan
 Sqrt/Log/Ln/Inv
 FFT real – 128/256/512
 FFT complex – 128/256/512
 Filters FIR (order N)
 Filters IIR (order N bi-quads)
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General Control
 PID 16- and 32-bit precision
 ADC software drivers
 PWM control software drivers
 2nd order plant
 GPIO software drivers
 Signal generators (sine, ramp…)
 Period and frequency
measurement
Communications Support
 SPI (hardware) and VSPI
(software) drivers
 EEPROM interface driver
(SPI format)
 SCI (UART) packet driver
 I2C (slave + master)
software driver
 EEPROM interface driver
(I2C format)
 CAN low-level driver
Foundation Software Libraries for
Specific Technology Segments
Digital Motor Control (DMC)
Sensorless and sensored solutions:
 AC Induction (ACI) motors scalar
and vector control
 Permanent Magnet Synchronous
Motors (PMSM) vector control
 BrushLess DC (BLDC) motors
trapezoidal control
 Switched Reluctance (SR) motors
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Power Conversion
 Four-stage uninterruptible
power supply (UPS)
 Power factor correction
Optical Networks (ONet)
 Collection of
communications modules
 Collection of control and
peripheral drivers
MIPS/Size/Cost = “Sweet Spot”
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MIPS: 40
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Size: 7 mm x 7 mm
(5/16” x 5/16”)
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Cost: US $2 (ROM)
US $5 (Flash)
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Example 1 – “Intelligent Cooling”
Rack Fan
Equipment
Racks
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LC2401A
DSP
COMMS ADC PWM
Example 1 – “Intelligent Cooling”
PMSM
3 phase
PWM
ADC
Network
DSP Software Solution
 Position
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estimation
(sliding mode observer)
 Space vector PWM
 Coordinate transforms
 Phase current
reconstruction
 Current PID loop x 2
 Speed PID loop
 Temperature loop (optional)
 Communications protocol
Signal
conditioning
Example 2 – “Power Tools”
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I/O
LC2401A
DSP
ADC PWM
Example 2 – Power Tools
PWM
Speed
control
ADC
I/O
FWD
REV
DSP Software Solution
 Speed
estimation
 N point FFT
 Filtering FIR/IIR
 “Other” math functions
 Phase current
measurements
 Current PID loop
 Speed PID loop
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Direction
control
Signal
conditioning
Brushed
DC
motor
Example 3 – Uninterruptible Power
Supply (UPS)
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Example 3 – UPS
V
I/O
LF24xx
or
F28xx
DSP
ADC PWM
V
HiV
LoV
PWM
ADC
I
V
I/O
HiV
DSP Software Solution
 Current/Voltage
PID loops
 Voltage boost control
 Battery charging control
 Line voltage synthesis +
regulation
 Line monitoring and switch
over control
 Power factor correction
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I
V
I
V
Example 4 – High-End Multi-Axis Control
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Example 4 – High-End Multi-Axis Control
“DAC”
F28xx
DSP
“ADC”
“COMMS” ”I/O”
“User Interface”
PWM
ADC
“Network”
DSP Software Solution
 Multiple
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system (“algorithm”) instantiation
 Multi-tasking/multi-threading
 Low interrupt latency/Fast context save and restore
 High-level network protocols
 CAN (deviceNet, CANopen,…) and Ethernet (TCP/IP)
 Sensored control: 30 ~ 60 MIPS (3 axis)
 Sensorless hi-end control: 60 ~ 90 MIPS (3 axis)
Example 5 – Optical Networks (ONet)
Tunable Lasers
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Example 5 – ONet Tunable Lasers
Fiber
Laser
Thermistor
Photo
diode
Temp.
Heater
Laser diode
DSP Software Solution
 12-bit
LPF
Peltier
element
OUT_L
OUT_R
ADC (14 bits
with operating system)
 High-resolution PWMs
provide 12-bit DACs
@ 40 KHz
 Efficient 32-bit
precision-control loops
 Full C/C++
implementation
Intensity
LPF
LPF Pwr
H-Bridge Amp
IN_R
F2810
DSP
COMMS ADC
IN_L
PWM
Linear Amp
Vsupply
ADC
“Network”
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Conclusion
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DSP controller advancements (performance/price/
integration) have made digital control the preferred
solution over legacy analog approaches.
The DSP centric topology with A-to-D and D-to-A
interface to the real world is a simple yet very
powerful solution to most control problems.
Continually improving MIPS and A-to-D and D-to-A
fidelity is giving designers more freedom without
compromise.
The performance/price/size “sweet-spot” is here
now and it’s only going to get better!
DSP controllers are and will continue to be deployed
in many end equipments, including the most costsensitive ones.
Get Started Today with Digital Signal
Processors from Texas Instruments

Visit http://focus.ti.com/docs/general/symlink.jhtml?name=c2000promo1
for details on the following.

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Download the complimentary C2000™ DSP Foundation Software
Library. This collection of Digital Motor Control software modules
allows you to rapidly build or customize your own systems.
DSP Starter Kits (DSKs) are a low-cost, easy-to-use development
tool that allows you to explore the C2000 DSP architecture and
start designing today.
Comprehensive technical documentation including application
notes, data sheets, and more.
Order device samples.
Free online training.
For further information, search TI’s DSP KnowledgeBase:
www.ti.com/sc/dspkbaseoct
Check out the latest digital signal processing news in TI’s DSP
eNewsletter: eTech Innovations, Digital Signal Processing
Edition at www.ti.com/sc/etechdsppromo6