Improved Operating Efficiency; Reducing Motor Speed Fluctuation (Slip Compensation Function) - YASKAWA Varispeed G7 Series Instruction Manual

Improved Operating Efficiency

This section explains functions for improving motor operating efficiency.


Reducing Motor Speed Fluctuation (Slip Compensation Function)

When the load is large, the amount of motor slip also grows large and the motor speed decreases. The slip
compensation function controls the motor at a constant speed, regardless of changes in load. When the motor
is operating at the rated load, constant E2-02 (Motor Rated Slip) × the frequency in constant C3-01 is added to
the output frequency.
Related Constants
Con-
stant
Number
C3-01
C3-02
C3-03
C3-04
C3-05
* The factory setting will change when the control method is changed. The open-loop vector 1 factory settings are given.
-36
6
Name
Description
Display
Slip compensa- Used to improve speed accuracy
tion gain when operating with a load.
Usually setting is not necessary.
Adjust this constant at the follow-
ing times.
• When actual speed is low,
increase the set value.
Slip Comp Gain
• When actual speed is high,
decrease the set value.
Used as the applicable control
gain when using flux vector con-
trol.
Slip compensa- Slip compensation primary delay
tion primary time is set in ms units.
delay time Usually setting is not necessary.
Adjust this constant at the follow-
ing times.
• Reduce the setting when slip
Slip Comp
compensation responsive is
Time
slow.
• When speed is not stabilized,
increase the setting.
Slip compensa-
Sets the slip compensation limit
tion limit
as a percentage of motor rated
Slip Comp
slip.
Limit
Slip compensa- 0: Disabled.
tion selection 1: Enabled.
during regener- When the slip compensation
ation during regeneration function has
been activated, as regeneration
capacity increases momentarily, it
Slip Comp
may be necessary to use a braking
Regen
option (braking resistor, Braking
Resistor Unit or Braking Unit.)
Output voltage 0: Disabled.
limit operation 1: Enabled. (The motor flux will
selection be lowered automatically
when the output voltage
Output V limit
become saturated.)
Control Methods
Change
Setting Factory during
V/f
Range Setting Opera-
V/f with
tion
PG
0.0 to
1.0* Yes A No
2.5
200
0 to
No A No
ms
10000
*
0 to
200% No A No
250
0 or 1 0 No A No
0 or 1 0 No No No
MEMO
Open Open
BUS
Flux
Loop Loop
Regis-
Vec-
Vector Vector
ter
tor
1 2
A A No 20FH
A No No 210H
A No No 211H
A No No 212H
A A No 213H