Software Design
Designer Reference Manual
DRM028 — Rev 0
94
Software Design
MOTOROLA
5.5.4 Align State
In the align state the rotor position is stabilized by applying PWM signals
to only two motor phases (no commutation). When preset time-out
expires, then this state is finished. See
Figure 5-9
.
Figure 5-9. Align State
Scheduler
The scheduler handles the state transitions in the align state. The
dc-bus current measurement is done in OC interrupt service routine,
in order to keep synchronization with PWM cycle. After measurement
is made, the scheduler allows calculation by the current controller and
(CMD_F = 1)
IRRECOVERABLE OVER-CURRENT
ENTER
EXIT
SCHEDULER
ALIGN TIME-OUT EXPIRED
ISR
DONE
TIMER1 (TIM A CH1) INTERRUPT
FAULT
STATE
ALIGN TIME-OUT
CURRENT CONTROLLER
(CMD_F = 0)
CURRENT MEASUREMENT
OVER-CURRENT
DETECTION
CURRENT MEASUREMENT
IS DONE
CURRENT MEASUREMENT
IS DONE (CMD_F = 1)
RUN CONDITION
(STOP_F = 0)
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