5.3.3 Adaptive Control
In an adaptive control soft start, the soft starter adjusts the
current to start the motor within a specified time and uses
a selected acceleration profile.
NOTICE
Adaptive control cannot start the motor faster than a
direct on-line (DOL) start. If the time set in
parameter 1-6
Start ramp time
is shorter than the motor DOL start time,
starting current may reach DOL levels.
Every application has a particular starting profile based on
characteristics of the load and the motor. To suit the
requirements of different applications, adaptive control
offers 3 different starting profiles. Selecting a profile that
matches the inherent profile of the application can help
smooth out acceleration across the full start time. Selecting
a different adaptive control profile can neutralize the
inherent profile to some extent.
To use adaptive control to control starting performance:
1.
Select
Adaptive control
in
parameter 1-3 Start
Mode
.
2.
Set
parameter 1-6 Start Ramp Time
.
3.
Select the wanted profile in
parameter 1-13
Adaptive Start Profile
.
4.
Set
parameter 1-4 Current Limit
sufficiently high to
allow a successful start.
The first adaptive control start is a constant current start.
This start type allows the soft starter to learn the charac-
teristics of the connected motor. The soft starter uses this
motor data during subsequent adaptive control starts.
0
10%
20%
30%
40%
50%
Time
60%
70%
80%
90%
100%
4
17
7
H
A
5
07
.1
0
S
p
ee
d
1
2
3
1 Early acceleration
2 Constant acceleration
3 Late acceleration
4
Parameter 1-16 Start Ramp Time
Illustration 5.4
Parameter 1-13 Adaptive Start Profile
NOTICE
Adaptive control regulates the load according to the
programmed profile. Start current varies according to the
selected acceleration profile and the programmed start
time.
The soft starter has to learn the characteristics of a new
motor:
•
If replacing a motor connected to a soft starter
programmed for adaptive control starting or
stopping.
•
If the soft starter has been tested on a different
motor before actual installation.
If
parameter 1-1 Motor Full Load Current
or
parameter
1-12 Adaptive Control Gain
is changed, the soft starter
automatically relearns the motor characteristics.
5.3.4 Kick Start
Kick start provides a short boost of extra torque at the
beginning of a start, and can be used with current ramp or
constant current starting.
Kick start can be useful to help start loads that require
high breakaway torque but then accelerate easily (for
example flywheel loads such as presses).
700%
600%
500%
300%
100%
400%
200%
10%
20% 30% 40% 50%
Rotor speed (% full speed)
60% 70% 80% 90%
100%
17
7
H
A
5
0
8
.1
0
Cu
rr
en
t (
%
m
o
tor
f
u
ll
loa
d
c
ur
re
nt
)
1
5
4
6
3
2
1
Parameter 1-7 Kick Start Level
2
Parameter 1-8 Kick Start Time
3
Parameter 1-5 Initial Current
4
Parameter 1-6 Start Ramp Time
5
Parameter 1-4 Current Limit
6 Full voltage current
Illustration 5.5 Example of Rotor Speed when using Kick Start
Product Features
Operating Guide
MG17K602
Danfoss A/S © 05/2016 All rights reserved.
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