YASKAWA VARISPEED-616G5, Instruction Manual

Page: 188 / 355

Advanced Operation
7.3.7 Operation Selection when Output Voltage Saturated
7 - 34
Motor Iron-core Saturation Coefficients 1, 2: E2-07, E2-08
User
Change
during Setting Factory
Valid Access Levels
User
Constant
Number
Name
g
during
Opera-
tion
Setting
Range
Unit Factory
Setting
V/f
Control
V/f with
PG
Open
Loop
Vector
Flux
Vector
E2-07
Motor iron-core sat-
uration coefficient 1
×
0.00 to 0.50 − 0.50
× ×
A A
E2-08
Motor iron-core sat-
uration coefficient 2
×
0.00 to 0.75 − 0.75
× ×
A A
D
Constants E2-07 and E2-08 are not required when using the motor at or below the rated frequency.
D
Set these constants when operating at a frequency higher that the motor’s rated frequency. Set the fol-
lowing values:
•
Motor iron-core saturation coefficient 1: Iron-core saturation coefficient when magnetic flux is
50%.
•
Motor iron-core saturation coefficient 2: Iron-core saturation coefficient when magnetic flux is
75%.
D
Normally these values aren’t shown on the motor nameplate, so it might be necessary to contact the
motor manufacturer. Operation will be possible with the factory-preset values.
Motor Mechanical Loss: E2-09
User
Change
during Setting Factory
Valid Access Levels
User
Constant
Number
Name
g
during
Opera-
tion
Setting
Range
Unit Factory
Setting
V/f
Control
V/f with
PG
Open
Loop
Vector
Flux
Vector
E2-09
Motor mechanical
loss
×
0.0 to 10.0 % 0.0
× × ×
A
D
Normally it isn’t necessary to change this setting in the following cases:
•
There is a large torque loss to the motor’s bearings
•
There is a large torque loss to a fan or pump
D
Set the mechanical loss as a percentage of the motor’s rated output power (W). Constant E2-09 is used
to compensate for torque lost mechanically in the motor.
J
Setting the Slip Compensation Gain: C3-01
User
Change
during Setting Factory
Valid Access Levels
User
Constant
Number
Name
g
during
Opera-
tion
Setting
Range
Unit Factory
Setting
V/f
Control
V/f with
PG
Open
Loop
Vector
Flux
Vector
C3-01
Slip compensation
gain
f
0.0 to 2.5
Mul-
tiple
1.0 B
×
B B
D
Normally it isn’t necessary to change this setting.
D
With flux vector control, constant C3-01 sets the motor’s temperature compensation gain. Adjust the
setting when a torque limit or torque control is being used and the output torque varies with the ambient
temperature.
D
This constant can be adjusted when the motor’s output torque changes at higher temperatures when
torque control or limits are used. The larger the setting, the larger the compensation will be.
7.3.7 Operation Selection when Output Voltage Saturated
The Inverter cannot output a voltage that is higher than the input voltage. If the output voltage command
to the motor (monitor constant U1-06) exceeds the input voltage in the high-speed region, the output volt-
age becomes saturated, and precise torque control is not longer possible during flux vector control.
Select one of the following methods to insure precise torque control.
J
Limited Output Voltage Operation: C3-06
User
Change
during Setting Factory
Valid Access Levels
User
Constant
Number
Name
g
during
Opera-
tion
Setting
Range
Unit Factory
Setting
V/f
Control
V/f with
PG
Open
Loop
Vector
Flux
Vector
C3-06
Limited output volt-
age operation
×
0, 1 1 0
× ×
A A
7