Mitsubishi Electric Q172DSCPU, Programming Manual

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8 - 2
8 AUXILIARY AND APPLIED FUNCTIONS
(2) Phase compensation of delay time of the output axis
Set delay time equivalent to the position deviation on the servo amplifier in
[Pr.444] Cam axis phase compensation advance time (150n,
150n) for the output axis. The delay time equivalent to position deviation
of the servo amplifier is calculated using the following formula.
Delay time [ μ s] =
1000000
Servo parameter "Model loop gain (PB07)"
(Note): When the feed forward gain is set, the delay time is set to a smaller value
than the value listed above.
The model loop gain will change when the gain adjustment method is auto tuning
mode 1 or 2. The model loop gain must not be changed on the axis executing
phase compensation through preventing change with the manual mode or
interpolation mode setting.
(3) Setting example
When axis 1 is synchronized with an incremental synchronous encoder axis, the
phase compensation advance time is set as follows.
(If the operation cycle is as 1.77 [ms] and model loop gain of axis 1 is as 80.)
Setting item Setting value
[Pr.326] Synchronous encoder axis
phase compensation advance time
(10n, 10n) 4395 [ μ s]
(Reference: Delay time peculiar to system for a
synchronous encoder axis)
[Pr.444] Cam axis phase compensation
advance time
(n, n)
1000000
80
= 12500 [ μ s]
When overshoot or undershoot occurs during acceleration/deceleration, set a
longer time for the phase compensation time constant.