Hitachi SJ Series, User Manual

Page: 244 / 786

12-9-27
Chapter 12 Inverter Function
12.9.13 Use V/f control with sensor
(constant torque
characteristics)
• To conduct a V/f control with a high revolution
accuracy by use of the revolution-speed feedback
of a motor.
• To make the motor follow the command frequency
accurately for the purpose of calculating the turns
or the like.
• The feedback of the encoder signal from the motor
allows highly accurate frequency control.
• For the adjustment of V/f control (constant torque
characteristics), see "12.9.2 Drive with V/f control
(constant torque characteristics)."
Parameter
• When [CA-90] = 02, Input terminals [A] and [B] are
switched to the terminals for feedback control.
When [CA-90]
≠ 02, terminals [EA] and [EB] of the
feedback option P1-FB are enabled.
See "12.9.17 Use encoder."
• In the V/f control with feedback (FB), a correction of
PI control is conducted on the command frequency
for the fed-back frequency to control the motor.
Item Parameter Data Description
Control mode [AA121] 04
To use V/f control with sensor (constant torque
characteristics).
Control with sensor slip
compensation P gain
[Hb170] 0~1000(%)
This is the P gain for the slip compensation of
control with sensor.
Control with sensor
slip compensation
I gain
[Hb171] 0~1000(%)
This is the I gain for the slip compensation of control
with sensor.
Ｑ
Ａ
！
Output
frequency
Feedback
Frequency-volt
age control
Control
frequency
M
+
Deviation ε
Kp (1+ )
1
Ti•S
+
+
PI control
Kp: proportional gain setting; Ti: integral time; s: operator; ε : deviation
Ki: integral gain setting (Ki = Ti/Kp)
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