B6: Dwell Function; B7: Droop Control (Clv, Clv/Pm) - YASKAWA A1000 HHP Programming Manual

Goal
Suppress long cycle oscillations
(longer than the integral time setting)
Suppress short cycle oscillations
u

b6: Dwell Function

The Dwell function temporarily holds the frequency reference at a predefined value for a set time then continues accelerating
or decelerating.
The Dwell function helps prevent speed loss when starting and stopping a heavy load with induction motors. When running
a PM motor in V/f control, the pause in acceleration allows the PM motor rotor to align with the stator field of the motor and
reduce the starting current.
Figure 1.24 illustrates how the Dwell function works.
Note: Set the stopping method to "Ramp to Stop" (b1-03 = 0) to use the Dwell function.
n b6-01, b6-02: Dwell Reference, Dwell Time at Start
Parameter b6-01 determines the frequency that is held for the time set in b6-02 during acceleration.
No.
b6-01
b6-02
n b6-03, b6-04: Dwell Reference, Dwell Time at Stop
Parameter b6-03 determines the frequency that is held for the time set in b6-04 during deceleration.
No.
b6-03
b6-04
u

b7: Droop Control (CLV, CLV/PM)

Note: PM motor control modes are not available in A1000 HHP drive models.
YASKAWA ELECTRIC SIEP YEAHHP 01B YASKAWA AC Drive – A1000 HHP Programming Manual
Tuning Procedure
Increase the integral time (b5-03)
• If oscillation cycle time is close to the
derivative time, reduce the derivative
time (b5-05).
• If the derivative time is set to 0.00 s and
oscillations are still a problem, reduce
the proportional gain (b5-02) or increase
the PID primary delay time (b5-08)
OFF
Run Command
Output Frequency
b6-02
Figure 1.24 Dwell Function at Start and Stop
Name
Dwell Reference at Start
Dwell Time at Start
Name
Dwell Reference at Stop
Dwell Time at Stop
Response
Response
ON OFF
b6-01
b6-03
b6-04
Setting Range
0.0 to 400.0 Hz
0.0 to 10.0 s
Setting Range
0.0 to 400.0 Hz
0.0 to 10.0 s
1.2 b: Application
Result
Before adjustment
After adjustment
Time
Before adjustment
After adjustment
Time
Default
0.0 Hz
0.0 s
Default
0.0 Hz
0.0 s
1
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