Transcript ppt
Andy Lian (EE)
Gabriel Miranda (EE)
Andrew Perez (EE)
Chris McManus (EE)
Drew Pearson (EE)
April 25, 2011
Design motor control system for the Solar
Jackets solar racing vehicle
Continuing work from previous group
Fall 2010
System responsibilities:
Electric motor operation
Central communication between vehicle
subsystems
Dynamic control of air gap motor
Functional cruise control using SBC
Regenerative braking
Load testing
Communication with vehicle subsystems
Load testing setup conducted with
motor/generator setup
Air gap control via relay system and switch
Cruise control
Throttle control
Communications
RS-485
▪ MPPT
▪ Battery Management
RS-232
▪ Motor Controller
USB
▪ HMI
Digital I/O
▪ Window Lift Motor
▪ Cruise Control & Air Gap
Switches
A/D Converter
▪ 10-Turn Potentiometer
Communications
RS-485
▪ MPPT
▪ Battery Management
RS-232
▪ Motor Controller
USB
▪ HMI
Digital I/O
▪ Window Lift Motor
▪ Cruise Control & Air Gap
Switches
A/D Converter
▪ 10-Turn Potentiometer
Communications
RS-485
▪ MPPT
▪ Battery Management
RS-232
▪ Motor Controller
USB
▪ HMI
Digital I/O
▪ Window Lift Motor
▪ Cruise Control & Air Gap
Switches
A/D Converter
▪ 10-Turn Potentiometer
Communications
RS-485
▪ MPPT
▪ Battery Management
RS-232
▪ Motor Controller
USB
▪ HMI
Digital I/O
▪ Window Lift Motor
▪ Cruise Control & Air Gap
Switches
A/D Converter
▪ 10-Turn Potentiometer
Communications
RS-485
▪ MPPT
▪ Battery Management
RS-232
▪ Motor Controller
USB
▪ HMI
Digital I/O
▪ Window Lift Motor
▪ Cruise Control & Air Gap
Switches
A/D Converter
▪ 10-Turn Potentiometer
Communications
RS-485
▪ MPPT
▪ Battery Management
RS-232
▪ Motor Controller
USB
▪ HMI
Digital I/O
▪ Window Lift Motor
▪ Cruise Control & Air Gap
Switches
A/D Converter
▪ 10-Turn Potentiometer
Ethernet
Telnet
▪ Login
FTP
▪ File Transfer
Default IP Config
▪ 192.168.0.50
▪ 255.255.255.0
▪ 192.168.0.255
motord
Motor control daemon
Handles state variable generation, cruise control, air
gap control, & log file generation
mcon
Allows discrete user control of motor controller
mmon
Allows monitoring of state variables through terminal
capture
Continuously captures state variable data and saves it
to specified CSV file
Features
Runs on startup
Serial timeout and recovery
Log file generation
Cruise control
Air gap control
State variable generation as separate file accessible
by other programs
RS-485 communication is handled separately by a
stand alone program still under development
▪ Pavel has been heading up this effort
▪ These programs communicate using the state variable file
Features
Discrete user control
Serial line flushing
Verbose debug mode
▪ Directly monitor message
and response registers
Features
Continuously monitors
state variables
Displays on terminal
Non-intrusive
Simple
Features
Continuously monitors
state variables
Stores data in CSV file
Easy import into Excel
Example program call
▪ capture /var/capture.csv
Controller prevents
change from serial to
discrete or vice-versa
while coasting
Solution:
Serial
Keep controller in serial
mode
Use SBC to read
controller values
Discrete
FIRST Robotics
Window Lift
Motor
Custom Mounting
Gear
Currently only one speed, fast
Possibility of a slow speed
Add extra relay to turn a resistor on/off
▪ Gives option of both a fast and a slow speed
Add resistor to existing circuit
▪ One speed, slow
Need to ensure torque is adequate
Actual motor operating speed to be verified
Relay controlled
Directional
switch on control
box sends signal
to SBC
SBC controls
relays
Air Gap Adjustment
Switch
Input 12V
Input 12V
SBC Controls
Input 12V
SBC Controls
On/Off Relay
Input 12V
SBC Controls
On/Off Relay
Forward/
Reverse Relay
Input 12V
SBC Controls
On/Off Relay
Forward/
Reverse Relay
Output to
Motor
10 Turn potentiometer
In-line with air gap
screw
Measure voltage on
wiper to determine air
gap’s position
Motor-generator
setup with resistor
box
• Provided variable
loading to verify:
•
• General motor
functionality
• Cruise control
capability
• Control in throttle
mode
Motor control setup
Generator
Added to provide load for motor
Connected to motor via flange
Resistor Box
Connected to generator
Decrease resistance to increase load on motor
Allowed simulation of drive cycles
Normal operation of motor under variable
load was successful
Operation of cruise control under variable
load was effectively verified
Throttle control mode was tested and
debugged
Data was gathered and various load profiles
were created
Phase Current vs Time
Phase Current (A)
6
5
4
3
2
Phase current
remains constant
1
Proportional to
0
0
20
40
60
80
100
torque
Time (s)
Speed vs Time
120
Speed (Hz)
100
80
60
40
20
0
0
20
40
60
Time (s)
80
100
As load increases
speed decreases
Phase Current vs Time
Phase Current (A)
30
25
20
Phase current
varies
As load changes
speed remains
constant
15
10
5
0
0
20
40
60
80
100
120
140
Time (s)
Speed vs Time
120
Speed (Hz)
100
80
60
In cruise control
40
20
0
0
20
40
60
80
Time (s)
100
120
140
Use of pot to judge closeness to air gap
extremes (ADC)
Testing of air gap adjustment system after
mounting onto gear
Communication with other subsystems
Test refurbished motor
Mounting motor onto vehicle
Motor functionality
Cruise (speed) control
Manual (throttle) control
Cruise control
Maintain set speed under variable load
Disengages when braking
Air gap adjustment via SBC
Event logging