Mitsubishi Electric Q172DSCPU, Programming Manual

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8 AUXILIARY AND APPLIED FUNCTIONS
8. AUXILIARY AND APPLIED FUNCTIONS
8.1 Phase Compensation Function
In synchronous control, delays in progresses, etc. cause the phase to deviate at the
output axis motor shaft end with respect to the input axis (servo input axis or
synchronous encoder axis). The phase compensation function compensates in this
case so that the phase does not deviate.
Phase compensation can be set for the input and the output axis. It is possible to
compensate using the delay time peculiar to the system based on the servo input axis
or the synchronous encoder axis on the input axis side. It is also possible to use a
compensation delay time equivalent to the position deviation for each servo amplifier
on the output axis side.
(1) Phase compensation on delay time of the input axis
Set delay time peculiar to the system in the phase compensation advance time of
the input axis ([Pr.302] Servo input axis phase compensation advance time
(n, n), [Pr.326] Synchronous encoder axis phase
compensation advance time (10n, 10n)).
The command generation axis does not have the phase compensation function
since the delay time specific to the system is 0.
The delay time peculiar to the system is shown below.
(a) Delay time peculiar to the system for a servo input axis
[Pr.300] Servo input axis type
Operation
cycle [ms]
Current feed value Real current value
Command to servo
amplifier
Feed back value
0.22 0 [ μ s] 945 [ μ s] 0 [ μ s] 945 [ μ s]
0.44 0 [ μ s] 1834 [ μ s] 0 [ μ s] 1834 [ μ s]
0.88 0 [ μ s] 3612 [ μ s] 0 [ μ s] 3612 [ μ s]
1.77 0 [ μ s] 3589 [ μ s] 0 [ μ s] 3589 [ μ s]
3.55 0 [ μ s] 8945 [ μ s] 0 [ μ s] 8945 [ μ s]
7.11 0 [ μ s] 19612 [ μ s] 0 [ μ s] 19612 [ μ s]
(b) Delay time peculiar to the system for a synchronous encoder axis
[Pr.320] Synchronous encoder axis type
Operation
cycle [ms]
Incremental synchronous
encoder
Absolute synchronous
encoder
Synchronous encoder via device
0.22 695 [ μ s] 603 [ μ s] 695 + Input value refresh timing [ μ s]
0.44 1255 [ μ s] 1400 [ μ s] 1255 + Input value refresh timing [ μ s]
0.88 2578 [ μ s] 2717 [ μ s] 2578 + Input value refresh timing [ μ s]
1.77 4395 [ μ s] 4505 [ μ s] 4395 + Input value refresh timing [ μ s]
3.55 7947 [ μ s] 8061 [ μ s] 7947 + Input value refresh timing [ μ s]
7.11 18604 [ μ s] 18728 [ μ s] 18604 + Input value refresh timing [ μ s]