Team MotorBoard
Efficient Motor Control and Power Conversion System
Critical Design Review
24 February 2009
Nicholas Barr, Daniel Fargano, Kyle Simmons, Marshall Worth
Overview
Purpose & Specifications
System Description
Controller Circuit
Power Converter
Other parts and purchases
Updated Labor Distribution
Updated detailed schedule
Questions/Suggestions and Comments
Purpose and Specifications
 Provide a general purpose motor power system and
controller
 More specifically will be used in the IEEE Future
Energy Challenge ‘09
 30 N-m Cold Torque
 3000 Rpm 3-5 seconds
 1 KW Power
 NEMA Frame 56
Motor Requirements
Torque Characteristics
System Description
Control System
• Arm7
Microcontroller
• Built in PWM
• Gate Drivers for
IGBTs
Power System
• Bi-Directional BuckBoost Converter,
more efficient by
isolating the buck
and boost sections
• 3-Phase Voltage
Inverter
System Diagram
Control System
NXP LPC2148FBD64-S
LPC-P2148 Olimex devo board
Crossworks-ARM
• Program Memory Size: 512KB
• RAM Size:
40KB
• Package / Case:
64-LQFP
• Speed: 60MHz
• Core Processor:
ARM7
• Data Converters:
A/D 14; D/A 1
• Core Size:
16/32-Bit
• Interface:
I²C, SPI, SSP, UART, USB
Control Algorithm
The objective of
the controls
algorithm is to
sense a set of
The objective
of the
inputs
from the
controls algorithm is to
motor
and
sense a set
of inputs
from
the
motor and
control
board
control board and
and
produce
a
produce
a corresponding
3-phase output voltage.
corresponding
3-phase output
voltage.
First we sample
the current and
voltage at phase
A,B and C of the
motor as well as
First
sample the
theweDC-DC
current in phase A,B and
output
C
as well as voltage.
the position
and speed of the rotor
Additionally
we
shaft
sample the
position and
speed of the
rotor shaft.
Second we
determine
the motor
Second we determine
operating
the motor operating
mode,
motoring
mode
and or
generating, and the
the
desired
desired
speed of
operation.
speed of
operation.
From these
Finally the controller
quantities
will determine the
the desired
appropriate duty cycle
Finallyon
the the
controller
DC-DC
to emit
IGBT
will determine the
converter
gate
drivers’
input
appropriate duty cycle toin
emit on the IGBT gate
From these quantities order to produce the
output
driver input in order to
the desired DC-DC
produce the desired
voltage
converterand
output voltagedesired voltage at both
voltage at both the
and phase
phase
A,BA,B and C the output
DCoutput of of
the the
DC-DC
voltages are calculated.
converter
as
well
as
the
and C
DC converter as well as
phase A,B and C voltages
voltages
the phase
A,B
and C
produced
by the
inverter.
are
voltages produced by
calculated.
the inverter.
Vector Controller
Clark Transform
isa  isb  isc  0
_
is  k (isa  aisb  a 2isc )
2
3
a  e j 2 / 3 , a 2  e j 4 / 3
k
_
is  is  jis
1
1
is  k (isa  isb  isc )
2
2
3
is  k
(isb  isc )
2
Park Transform
d
 sd   s sq
dt
d
u sq  Rs isq   sq   s sd
dt
d
urd  0  Rr ird   rd  ( s   ) rq
dt
d
urq  0  Rr irq   rq  ( s   ) rd
dt
 sd  Ls isd  Lmird
u sd  Rs isd 
 sq  Ls isq  Lmirq
 rd  Lr ird  Lmisd
 rq  Lr irq  Lmisq
te 
3
p p ( sd isq  sqisd )
2
PWM
CrossWorks
Code written for
Development board using
CrossWorks
Power System
195VDC line to supply
from variable AC source
Large DC supply line
capacitor
Bidirectional Buck-Boost
Converter
Bidirectional DC  3phase AC inverter
Power System - Overview
Power System – Cascaded B/B
Power System - 3φ Inverter
Power System – Switches
 Power MOSFET
 high-frequency operation
 low-voltage drop (low power losses)
 saturation temperature sensitivity
 IGBT
 low drive current
 fast switching time
 higher voltage drop (higher
conduction losses)
 IGBT w/Diode Co-pack
 Voltage - Collector Emitter Breakdown
(Max):600V
 Current - Collector (Ic) (Max):85A
Power System – Driver
 Configuration:High and Low
Side, Independent
 Bootstrap circuit designed to
prevent gate voltage from
dropping below minimum
gate threshold voltage
Power System – Driver
DC-DC Bi-Directional Buck-Boost
Simulated 3 Phase Waveforms
Simulated 3 Phase Waveforms
Sensors
3 Hall-effect
current sensors
for a,b,c line
detection
• After attending APEC Dan needs to call
his contact at GMW or TEG to get free
Hall Effect Sensors
Quadrature
encoder (fancy
shaft encoder)
• Most likely optical
• Prefer absolute position sensor
• Old team lists having this and could
possibly find and use theirs
DC line voltage
sensor
• APEC -> Call TEG for possible free
sample
• Resistor Divider Network (Power Loss)
Optional
(safety):
• Temperature sensor
Parts List – Mass Production
Item
Part #
Quantity
Unit Price
Total Price
Mass
Production Cost
Caps
495-3502-ND
4
9.35
$37.4
$8.35
Inductors
M8380-ND
1
9.56
$9.56
$1.39
IGBTs
IRG4PSC71U 10
DPBF
10.68
$106.80
$18.70
Drivers
IR21132PBF-ND
5
5.57
$27.85
$5.96
Bootstraps
XXX
5
1.19
$5.95
$1.49
MPU
568-1765-ND
1
11.20
$11.20
$2.80
Controls
XXX
1
31.76
$31.76
$7.94
Motor
Baldor
1
326.90
$326.90
$50
Package
XXX
1
18.20
$18.20
$3.64
$574.54
$100.00
Total
Division Of Labor
Converter
• Nick
• Marshall
PCB Design
• Dan
• Marshall
Custom
Footprints
• Kyle
• Dan
• Marshall
Inverter
• Dan
• Kyle
Testing
• All
Software
• Nick
• Marshall
Documentation
• All
Presentation
• All
Project Milestones
Milestone I
Milestone II
• Power Electronics
hardware working
on perf-board
• Controls driven
by Dev Board (no
feed back loops)
• First revision of
controls PCB
completed and
sent out.
• Power electronics
PCB designed and
sent out for
fabrication
• Controls PCB
built and
populated
• Full controls
algorithm with
working feed-back
loops.
EXPO
• Final debug
finished
• Packaging
designed done
and project
packaged
• Documentation
done
Questions?