Omron VARISPEED G7 -, Instruction Manual

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Individual Functions
6-
127
Gain Adjustment for Speed Control during V/f Control with PG
When using V/f control with PG, set the proportional gain (P) and the integral time (I) at E1-09 (minimum out-
put frequency) and E1-04 (maximum output frequency).
Fig 6.72 Speed Control Gain Integral Time Adjust-
ment for V/f Control with PG shows how the proportional gain and integral time change in linear fashion based
on the speed.
Fig 6.72 Speed Control Gain Integral Time Adjustment for V/f Control with PG
Gain Adjustments at Minimum Output Frequency
Operate the motor at the minimum output frequency. Increase C5-03 (ASR proportional gain 2) to a level
where there is no oscillation. Decrease C5-04 (ASR integral time 2) to a level where there is no oscillation.
Monitor the Inverter's output current and verify that it is less than 50% of the Inverter rated current. If the out-
put current exceeds 50% of the Inverter's rated current, decrease C5-03 and increase C5-04.
Gain Adjustments at Maximum Output Frequency
Operate the motor at the maximum output frequency. Increase C5-01 (ASR proportional gain 1) to a level
where there is no oscillation. Decrease C5-02 (ASR integral time 1) to a level where there is no oscillation.
Fine Adjustments
When you want even finer gain adjustment, adjust the gain while observing the speed waveform. The adjust-
ment method is the same as that for vector control.
Enable integral operation during acceleration and deceleration (by setting F1-07 to 1) when you want the
motor speed to closely follow the frequency reference during acceleration and deceleration. Reduce the setting
of C5-01 if overshooting occurs during acceleration, and reduce the setting of C5-03 and increase the setting
of C5-04 if undershooting occurs when stopping. If overshooting and undershooting cannot be eliminated by
adjusting only the gain, reduce the value of C5-05 speed control and reduce the limit of the frequency refer-
ence compensation value.
Droop Control Function
Droop control is a function that allows the user to set the amount of motor slip.
When a single load is operated with two motors (such as in a crane conveyor), a high-resistance motor is nor-
mally used. This is to use torque characteristics that exhibit proportion movements due to changes in the sec-
ondary resistor to maintain torque balance with the load and overall speed balance with the load.
If droop control is used, a high-resistance motor characteristics can be set for a general-purpose motor.
P and I setting
Motor speed (Hz)
E1-04
Max. output frequency
0
P = C5-03
I = C5-04
P = C5-01
I = C5-02
E1-09
Min. output frequency