Danfoss VLT AutomationDrive FC 302 - Page 184

Parameter 1-01 Motor Control Principle is set to [1] VVC
+
and parameter 1-00 Conguration Mode is set to [0] Speed open loop.
If parameter 1-00 Conguration Mode is set to [1] Speed closed loop, the resulting reference is passed from the ramp
limitation and speed limitation into a speed PID control. The speed PID control parameters are located in parameter group
7-0* Speed PID Ctrl. The resulting reference from the speed PID control is sent to the motor control limited by the frequency
limit.
Select [3] Process in parameter 1-00 Conguration 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 in parameter groups 7-2* Process Ctrl. Feedb
and 7-3* Process PID Ctrl.
11.2.7.2 Control Structure in Flux Sensorless
+
_


+
_
130BA053.11
Ref.
Cong. mode
P 1-00
P 7-20 Process feedback
1 source
P 7-22 Process feedback
2 source
Process
PID
P 4-11 Motor speed
low limit [RPM]
P 4-12 Motor speed
low limit [Hz]
P 4-14 Motor speed
high limit [Hz]
P 4-13 Motor speed
high limit [RPM]
Low
High
Ramp
P 3-**
+f max.
P 4-19
Max. output
freq.
Motor
controller
-f max.
Speed
PID
P 7-0*
Illustration 11.9 Control Structure in Flux Sensorless Open Loop and Closed-loop Congurations
In Illustration 11.9, the resulting reference from the reference handling system is fed through the ramp and speed limitations
as determined by the parameter settings indicated.
Parameter 1-01 Motor Control Principle is set to [2] Flux Sensorless and parameter 1-00 Conguration Mode is set to [0] Speed
open loop. An estimated speed feedback is generated to the speed PID to control the output frequency. The speed PID must
be set with its P, I, and D parameters (parameter group 7-0* Speed PID control).
Select [3] Process in parameter 1-00 Conguration Mode to use the process PID control for closed-loop control of the
controlled application. The process PID parameters are found in parameter groups 7-2* Process Ctrl. Feedb and 7-3* Process
PID Ctrl.
Basic Operating Principles ... VLT® AutomationDrive FC 302
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