B7: Droop Control (Clv, Clv/Pm) - YASKAWA A1000 Series Technical Manual

5.2 b: Application

◆ b7: Droop Control (CLV, CLV/PM)

Droop control can automatically balance the load level between two motors that drive the same load, such as in traverse
cranes applications. It must be activated in one of the two drives that control these motors. The drive in which Droop
control is activated will automatically reduce the speed if the torque reference rises, and increase the speed if the torque
reference falls again, thereby shifting the load from one motor to the other.
Note: Disable Feed Forward (n5-01 = 0) whenever using Droop control.
Figure 5.27
Motor A runs faster than B, pulling more load
A
= 100% Load
B
= 80% Load
Droop Control increases the speed reference in
drive B accomplishing load balance
b7-01: Droop Control Gain
■
Sets the amount of speed reduction when the torque reference is 100%. The gain is set as a percentage of the maximum
output frequency. A setting of 0.0% disables the Droop control function.
No.
b7-01
Figure 5.28
b7-02: Droop Control Delay Time
■
The setting in b7-02 adjusts the responsiveness of Droop control. Reduce the setting if the reaction time is too long, and
increase it if hunting occurs.
No.
b7-02
b7-03: Droop Control Limit Selection
■
Enables or disables the droop control limit.
No.
b7-03
Setting 0: Disabled
Setting 1: Enabled
162
A
= 90% Load
f = constant
ref_A
f increase
ref_B
B
= 90% Load
Figure 5.27 Droop Control in a Traverse Application
Parameter Name
Droop Control Gain
Speed
Speed reference
0
Figure 5.28 Droop Control Gain
Parameter Name
Droop Control Delay Time
Parameter Name
Droop Control Limit Selection
Motor B runs faster than A, pulling more load
A
= 80% Load
f
ref_A
B
= 100% Load
Droop Control decreases the speed reference in
drive B accomplishing load balance
Droop control gain
b7-01
Torque
100%
YASKAWA ELECTRIC SIEP C710616 27C YASKAWA AC Drive A1000 Technical Manual
A
= 90% Load
= constant
common_TMonly
f decrease
ref_B
B
= 90% Load
Setting Range
0.0 to 100.0%
common_TMonly
Setting Range
0.03 to 2.00 s
Setting Range
0, 1
Default
0.0%
Default
0.05 s
Default
1