
B-65270EN/05 4.SERVO FUNCTION DETAILS
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4.5.5 Current Loop 1/2 PI Control Function
(1) Overview
To improve servo performance in high-speed and high-precision
machining, high-speed positioning, ultrahigh-precision positioning,
and so forth, a velocity loop gain as high as possible needs to be set
stably.
To set a high velocity loop gain stably, the response of the current
loop needs to be improved.
The current loop 1/2 PI control function enables the response of the
current loop to be improved.
(2) Series and editions of applicable servo software
(Series 30i,31i,32i)
Series 90D0/A(01) and subsequent editions
Series 90E0/A(01) and subsequent editions
(Series 15i-B,16i-B,18i-B,21i-B,0i-B,0i Mate-B, Power Mate i)
Series 9096/A(01) and subsequent editions
Series 90B0/A(01) and subsequent editions
Series 90B1/A(01) and subsequent editions
Series 90B6/A(01) and subsequent editions
(Series 0i-C,0i Mate-C,20i-B)
Series 90B5/A(01) and subsequent editions
(3) Control method
As shown in Fig. 4.5.5, in the area where a small current flows, a
current loop calculation is based on PI control rather than on the
conventional IP control method. When a large current flows, the
control method returns to IP control to suppress a current overshoot.
p
PK1/s
PK2
+
−
-
The proportional from the command is added to PWM calculation.
Torque command
Switching to the
intermediate state of PI
control and I-P control
PWM command
Fig. 4.5.7 Block diagram of current loop 1/2PI control
(4) Setting parameters
<1> Enabling the current loop 1/2 PI control function at all times
#7 #6 #5 #4 #3 #2 #1 #0
1743 (FS15i)
CRPI
2203 (FS30i, 16i)
CRPI (#2) 1: To enable the current loop 1/2 PI control function
<2> To enable the function for cutting only, use the following bit in
addition to the previous bit: