Danfoss VLT AutomationDrive FC 301 Programming Manual page 54

Parameter Descriptions
Application-specific adjustment when running VVC
+
VVC is the most robust control mode. In most situations,
it provides optimum performance without further
adjustments. Run a complete AMA for best performance.
Application-specific adjustment when running flux
3 3
Flux control principle is the preferred control principle for
optimum shaft performance in dynamic applications.
Perform an AMA since this control mode requires precise
motor data. Depending on the application, further
adjustments may be required.
See Table 3.3 for application-related recommendations.
Application
Low-inertia applications
High-inertia applications
High load at low speed
No-load application
Flux sensorless control
principle only
Table 3.3 Recommendations for Flux Applications
52
®
VLT AutomationDrive FC 301/302
+
Settings
Keep calculated values.
Parameter 1-66 Min. Current at Low
Speed.
Increase current to a value between
default and maximum depending on
the application.
Set ramp times matching the
application. Too fast ramp-up causes
an overcurrent or overtorque. Too
fast ramp-down causes an
overvoltage trip.
Parameter 1-66 Min. Current at Low
Speed.
Increase current to a value between
default and maximum depending on
the application.
Adjust parameter 1-18 Min. Current at
No Load to achieve smoother motor
operation by reducing torque ripple
and vibration.
Adjust parameter 1-53 Model Shift
Frequency.
Example 1: If the motor oscillates at
5 Hz, and dynamics performance is
required at 15 Hz, set
parameter 1-53 Model Shift Frequency
to 10 Hz.
Example 2: If the application
involves dynamic load changes at
low speed, reduce
parameter 1-53 Model Shift Frequency.
Observe the motor behavior to
make sure that the model shift
frequency is not reduced too much.
Symptoms of inappropriate model
shift frequency are motor oscillations
or frequency converter tripping.
Danfoss A/S © 10/2019 All rights reserved.
3.2.4 PM Motor Set-up
NOTICE
Valid for FC 302 only.
This section describes how to set up a PM motor.
Initial programming steps
To activate PM motor operation, select [1] PM, non-salient
SPM in parameter 1-10 Motor Construction.
Programming motor data
After selecting a PM motor, the PM motor-related
parameters in parameter groups 1-2* Motor Data, 1-3* Adv.
Motor Data, and 1-4* Adv. Motor Data II are active.
The necessary data is on the motor nameplate and on the
motor datasheet.
Run a complete AMA using parameter 1-29 Automatic
Motor Adaptation (AMA) [1] Enable Complete AMA.
If a complete AMA is not performed, configure the
following parameters manually:
1. Parameter 1-30 Stator Resistance (Rs)
Enter the line-to-common stator winding
resistance (Rs). If only line-line data is available,
divide the line-line value by 2 to get the line-
common value.
2. Parameter 1-37 d-axis Inductance (Ld)
Enter the line-to-common direct axis inductance
of the PM motor.
If only line-line data is available, divide the line-
line value by 2 to get the line-common value.
3. Parameter 1-40 Back EMF at 1000 RPM
Enter the line-to-line back EMF of the PM motor
at 1000 RPM (RMS value). Back EMF is the voltage
generated by a PM motor when no frequency
converter is connected and the shaft is turned
externally. It is normally specified for nominal
motor speed or for 1000 RPM measured between
2 lines. If the value is not available for a motor
speed of 1000 RPM, calculate the correct value as
follows:
If back EMF is, for example, 320 V at 1800 RPM, it
can be calculated at 1000 RPM as follows:
Back EMF = (Voltage/RPM)x1000 =
(320/1800)x1000 = 178.
Test motor operation
1. Start the motor at low speed (100–200 RPM). If
the motor does not turn, check the installation,
general programming, and motor data.
2. Check if the start function in parameter 1-70 Start
Mode fits the application requirements.
Rotor detection
This function is the recommended selection for
applications where the motor starts from standstill, for
example pumps or conveyors. On some motors, a sound is
M0013101