Synrm Motor Set-Up With Vvc; Test Motor Operation; Rotor Detection; Parking - Danfoss VLT AutomationDrive FC 302 Programming Manual

Parameter Descriptions
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.
3 3
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
heard when the frequency converter performs the rotor
detection. This does not harm the motor.

Parking

This function is the recommended selection for
applications where the motor is rotating at slow speed, for
example windmilling in fan applications.
Parameter 2-06 Parking Current and parameter 2-07 Parking
Time can be adjusted. Increase the factory setting of these
parameters for applications with high inertia.
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.
Start the motor at nominal speed. If the application does
not run well, check the VVC
contains recommendations for various applications.
46
®
VLT AutomationDrive FC 301/302
+
+
PM settings. Table 3.4
Danfoss A/S © 10/2018 All rights reserved.
Application Settings
Low-inertia applications Increase parameter 1-17 Voltage filter
I /I <5 time const. by factor 5–10.
Load Motor
Reduce parameter 1-14 Damping
Gain.
Reduce parameter 1-66 Min. Current
at Low Speed (<100%).
Low-inertia applications Keep the default values.
50>I /I >5
Load Motor
High-inertia applications Increase parameter 1-14 Damping
I /I >50 Gain, parameter 1-15 Low Speed Filter
Load Motor
Time Const., and parameter 1-16 High
Speed Filter Time Const.
High load at low speed Increase parameter 1-17 Voltage filter
<30% (rated speed) time const.
Increase parameter 1-66 Min. Current
at Low Speed to adjust the starting
torque. 100% current provides
nominal torque as starting torque.
This parameter is independent of
parameter 30-20 High Starting Torque
Time [s] and parameter 30-21 High
Starting Torque Current [%]). Working
at a current level higher than 100%
for a prolonged time can cause the
motor to overheat.
Table 3.4 Recommendations for Various Applications
If the motor starts oscillating at a certain speed, increase
parameter 1-14 Damping Gain. Increase the value in small
steps. Depending on the motor, this parameter can be set
to 10–100% higher than the default value.
Application-specific adjustment when running flux
Flux control principle is the preferred control principle for
optimum shaft performance in dynamic applications.
Perform an AMA because this control mode requires
precise motor data. Depending on the application, further
adjustments may be required.
See chapter 3.2.3 Asynchronous Motor Set-up for application-
specific recommendations.

3.2.5 SynRM Motor Set-up with VVC

This section describes how to set up a SynRM motor with
+
VVC .
NOTICE
The SmartStart wizard covers the basic configuration of
SynRM motors.
Initial programming steps
To activate SynRM motor operation, select [5] Sync.
Reluctance in parameter 1-10 Motor Construction.
+
MG33MP02