Adaptive Control; Kick Start - Danfoss vlt soft starter mcd 500 Operating Manual

Product Features

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.
100%
90%
80%
70%
1
60%
50%
40%
2
30%
20%
3
10%
0
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
MG17K602
Operating Guide
4
Time
Danfoss A/S © 05/2016 All rights reserved.
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).
6
700%
600%
2
1
500%
400%
4
300%
200%
3
100%
10% 20% 30% 40% 50%
Rotor speed (% full speed)
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
5
60% 70% 80% 90% 100%
37
5 5