System concept, The application block diagram is shown in, Figure 2-1 – Motorola M68HC08 User Manual
Page 16: The sensorless, System description, Freescale semiconductor, inc
System Description
Designer Reference Manual
DRM028 — Rev 0
16
System Description
MOTOROLA
Figure 2-1System Concept
During the rotor alignment state, the dc-bus current is controlled by the
current PI regulator. In the other states (motor running), the phase
voltage (PWM duty cycle) is controlled by the speed PI regulator.
ADC
Speed PI
Regulator
HC08MR32
Power line
Actual Speed
PWM
BEMF Zero
Crossing
signal
Three-Phase
Inverter
3-ph
BLDC
Motor
START
STOP
SPEED
PWM
Generator
with
Dead Time
PC Master
SCI
3 phase BLDC
Power Stage
Commutation
Control
Zero Crossing
Period, Position
Recognition
Zero
Crossing
Duty
Cycle
Required
Speed
1/T
Commutation
Period
Zero Crossing
Time moment
3 BEMF Voltage
Zero Crossing
Comparators
Digital
Inputs
DC-Bus Voltage/
Current
Temperature
MUX
MUX
Command
Digital
Outputs
DC Bus Current &
DC Bus Voltage
Sensing
Current PI
Regulator
(for Alignment)
Required
Alignment
Current
Actual
Current
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