5.2 Spindle Axis Orientation
5-11
Spindle Axis
Operation
(2) QUICK_ORT Command Operation
Positioning
∗1.
If the latch is not completed (i.e., when the Latch Completed signal is FALSE), positioning is performed to a position
that can be reached by POS_TREF from the current position.
∗2.
The POS_TREF command can be used to limit the torque during deceleration and enable a more gradual stop.
• Executing the QUICK_ORT Command from a Speed Faster Than the Target Speed
If the QUICK_ORT command is executed from a speed that is slower than the target speed, the spindle motor
operates as follows:
1. The spindle motor accelerates while identifying the moment of inertia up to the target speed for speed con-
trol.
2. A latch is requested after the target speed is reached.
3. The control mode is changed from speed control to position control after the latch has been completed.
4. After changing to position control, positioning is performed towards the target position at the deceleration
rate that is calculated from the maximum torque and moment of inertia.
Absolute Speed
Basic Operation
Latching
Control
Mode
Current speed
≥
Target speed (before
latch completion)
The axis is decelerated to the target speed (TSPD) with speed control
using stepwise deceleration references. Moment of inertia identifica-
tion is performed during deceleration, and then a latch is requested
after the target speed is reached. After the latch operation has been
completed
*1
, positioning is performed to the target position using the
operation for when the current reference speed is less than or equal
to the target speed.
Executed.
Speed
Control
Current speed
≤
Target speed (before
latch completion)
The axis is accelerated to the target speed (TSPD) with speed control
using stepwise acceleration references. Moment of inertia identifica-
tion is performed during acceleration, and then a latch is requested
after the target speed is reached. After the latch operation has been
completed
*1
, positioning is performed to the target position using the
operation for when the current reference speed is less than or equal
to the target speed.
Executed.
Speed
Control
Current speed
≤
Target speed (after
latch completion)
Positioning is performed towards the target position with position
control according to the deceleration rate calculated from the maxi-
mum torque
*2
(POS_TREF) and moment of inertia. In this case, fol-
lowing performance is increased by using a torque feedforward that
is equal to the positioning torque reference that is specified in CMD
and in the speed feedforward to match the deceleration rate.
Completed.
Position
Control
QUICK_ORT
L_CMP
DEN
PSET
Speed
• Deceleration is started to the target speed with speed control.
ON
ON
ON
ON
Time
Target speed (TSPD)
•
Position control toward the target position is started.
•
The mode is changed to position control.
•
Latch is completed.
•
Latch request
•
Deceleration to the target speed is completed.
•
Moment of inertia identification