Chapter 7 Auxiliary And Applied Functions; Phase Compensation Function - Mitsubishi Electric R32MTCPU Programming Manual

7
AUXILIARY AND APPLIED FUNCTIONS
7.1

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.
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 (D14600+2n, D14601+2n)", "[Pr.326] Synchronous encoder axis phase compensation
advance time (D14820+10n, D14821+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.
■Delay time peculiar to the system for a servo input axis
Operation cycle [ms] [Pr.300] Servo input axis type
Current feed value
0.222 0[s]
0.444 0[s]
0.888 0[s]
1.777 0[s]
3.555 0[s]
7.111 0[s]
■Delay time peculiar to the system for a synchronous encoder axis
Operation cycle [ms] [Pr.320] Synchronous encoder axis type
Incremental synchronous
encoder
0.222 614[s]
0.444 1276[s]
0.888 2600[s]
1.777 4396[s]
3.555 7933[s]
7.111 18616[s]
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 (D15066+150n, D15067+150n)" for the output axis. The delay time equivalent to position deviation of the servo amplifier
is calculated using the following formula.
Delay time [μs] =
Servo parameter "Model loop gain (PB07)"
When the feed forward gain is set, the delay time is set to a smaller value than the value listed above.
Real current value
944[s]
1833[s]
3611[s]
5388[s]
8945[s]
19612[s]
Absolute synchronous encoder
968[s]
1871[s]
3638[s]
5422[s]
8980[s]
19648[s]
1000000
Command to servo Feedback value
amplifier
0[s] 944[s]
0[s] 1833[s]
0[s] 3611[s]
0[s] 5388[s]
0[s] 8945[s]
0[s] 19612[s]
Synchronous encoder via device
614+Input value refresh timing[s]
1276+Input value refresh timing[s]
2600+Input value refresh timing[s]
4396+Input value refresh timing[s]
7933+Input value refresh timing[s]
18616+Input value refresh timing[s]
7 AUXILIARY AND APPLIED FUNCTIONS
7.1 Phase Compensation Function
7
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