Control Structures; Control Structure In Vvc Plus Advanced Vector Control; Control Structure In Flux Sensorless - Danfoss VLT Decentral Drive FCD 302 Design Manual

Application Examples

4.5 Control Structures

4.5.1 Control Structure in VVC
4 4
Ref.
+

_
P 7-20 Process feedback
1 source
P 7-22 Process feedback
2 source
Illustration 4.15 Control Structure in VVC
In the configuration shown in Illustration 4.15, 1-01 Motor
Control Principle is set to [1] VVC
Mode is set to [0] Speed open loop. The resulting reference
from the reference handling system is received and fed
through the ramp limitation and speed limitation before
being sent to the motor control. The output of the motor
control is then limited by the maximum frequency limit.
If 1-00 Configuration Mode is set to [1] Speed closed loop
the resulting reference passes from the ramp limitation
and speed limitation into a speed PID control. The Speed
PID control parameters are located in the parameter group
7-0*. The resulting reference from the Speed PID control is
sent to the motor control limited by the frequency limit.
62
VLT
plus
Advanced Vector Control
P 4-13
Motor speed
high limit (RPM)
P 1-00
P 4-14
Con g. mode
Motor speed
high limit (Hz)
High
Low
P 4-11
Motor speed
Process
low limit (RPM)
P 4-12
Motor speed
low limit (Hz)
plus
Open Loop and Closed Loop Configurations
plus
and 1-00 Configuration
MG04H102 - VLT
®
Decentral Drive FCD 302
P 1-00
Con g. mode
P 3-**
Ramp
+

_
P 7-00 Speed PID
feedback source
Select [3] Process in 1-00 Configuration Mode to use the
process PID control for closed loop control of for example,
speed or pressure in the controlled application. The
Process PID parameters are located in parameter group
7-2* and 7-3*.

4.5.2 Control Structure in Flux Sensorless

Control structure in Flux sensorless open loop and closed
loop configurations.
®
is a registered Danfoss trademark
P 4-19
Max. output freq.
+f max.
Motor
controller
-f max.
P 4-19
Max. output freq.
P 7-0*
Speed Motor
PID controller
+f max.
-f max.