NXP Semiconductors 56F8000, Руководство по использованию

Страница: 15 / 28

9V DC
APMOTOR56F8000
Motor Control
Daughter Card
BLDC
motor
Hall Sensors
PWM1-6
P
W
M
Speed
Control
56F8013
G
P
I
O
S
C
I
PC Remote
Monitoring
DEMO56F8013
Commutation
Handler
Ω
Req
PI (Speed)
Controller
T
I
M
E
R
Speed
Calculation
Ω
Act
Duty Cycle
A
D
C
PI (Torque)
Controller
Under-Voltage
Fault Detection
Fault
LED
DC Bus Voltage
DC Bus Current
9V DC
APMOTOR56F8000
Motor Control
Daughter Card
BLDC
motor
Hall Sensors
PWM1-6
P
W
M
Speed
Control
56F8013
G
P
I
O
S
C
I
PC Remote
Monitoring
DEMO56F8013
Commutation
Handler
Ω
Req
PI (Speed)
Controller
T
I
M
E
R
Speed
Calculation
Ω
Act
Duty Cycle
A
D
C
PI (Torque)
Controller
Under-Voltage
Fault Detection
Fault
LED
DC Bus Voltage
DC Bus Current
Application Description
System Description, Rev. 1
Freescale Semiconductor 2-3
Preliminary
Figure 2-2. System Concept
The control process is as follows:
The state of the user interface is periodically scanned, while the speed of the motor is measured with each
new edge from the Hall sensors; only one phase is used for speed measurement. The speed command is
calculated according to the state of the control signals. The comparison between the actual speed
command and the measured speed generates a speed error, which is input to the PI Speed controller that
acts as an input to the PI Torque controller. Together with measured current, it forces the PI Torque
controller to generate a new corrected duty cycle. The duty cycle value, together with the commutation
algorithm, creates the PWM output signals for the BLDC power stage.
The Hall sensor signals are scanned independently of speed and torque controls. Each new coming edge
of any Hall sensor signal calls the interrupt routine, which executes the commutation algorithm.
If undervoltage occurs, the PWM outputs are disabled and the fault state is displayed.