Omron SYSDRIVE 3G3FV - Operation for Saturated Output Voltage; Setting Magnetic Flux Characteristics for Open-Loop Vector Control

6-6
6-1-4 Setting Magnetic Flux Characteristics for Open-loop
Vector Control
Set the following parameter to select the method for V/f calculation to determine the magnetic flux char -
acteristics.
The default setting does not normally need to be changed. Set the parameter if stable slip
compensation is required in the constant output area where the operating frequency is as high as or
higher than the rated frequency.
Parameter Display Setting Units Default
Valid access levels
number
py
name
g
range setting
V/f
Control
V/f with
PG
Open Loop
Vector
Flux
Vector
C3-05 Flux Se-
lect
0, 1 --- 0 --- Advanced ---
Settings
Setting Description
0 The calculation of magnetic flux in open-loop vector control is based on the output frequency after
slip compensation.
1 The calculation of magnetic flux in open-loop vector control is based on the output frequency with
the V/f characteristic (i.e., the value without slip compensation).
Note Set the parameter to 1 if the speed of the motor is unstable in the constant output area.
6-1-5 Operation for Saturated Output Voltage
Previously, the accuracy of motor speed for vector control was greatly reduced when the
limit of the Inverter ’s voltage output was approached (a voltage greater than that of the
input power supply cannot be output).
Set the following parameter to control the output voltage so that the limit will not be
reached, thus maintaining speed accuracy.
Parameter Display Setting Units Default
Valid access levels
number
py
name
g
range setting
V/f
Control
V/f with
PG
Open Loop
Vector
Flux
Vector
C3-06 Output V
limit
0, 1 --- 0 --- Advanced ---
Settings
Setting Description
0 Disabled. (There is no limit of output voltage saturation. Slip compensation is disabled when the
output voltage saturates.)
1 Enabled. (Output voltage saturation is suppressed to maintain speed control.)
Note 1. Set the parameter to 1 if accuracy of speed is required within the rated rpm range. This will
cause an increase of approximately 10% in the output current. Therefore, be sure that Invert -
er has more than sufficient output current.
Note 2. If
the Inverter ’ s input voltage is extremely lower than the rated motor voltage, the accuracy of
the speed of the motor may not be maintained even with the output voltage suppressed.
Advanced Operation Chapter 6