Autotune
17
Autotune Procedure for Sensorless Vector and Economizer
The purpose of Autotune is to identify the motor flux current and stator resistance
for use in Sensorless Vector Control and Economizer modes.
The user must enter motor nameplate data into the following parameters for the
Autotune procedure to obtain accurate results:
•
[Motor NP FLA]
•
[Motor NP Volts]
•
[Motor NP Hertz]
•
[Motor NP Power]
Next, the Dynamic or Static Autotune should be performed:
•
Dynamic - the motor shaft will rotate during this test. The dynamic autotune
procedure determines both the stator resistance and motor flux current. The test
to identify the motor flux current requires the load to be uncoupled from the
motor to find an accurate value. If this is not possible then the static test can be
performed.
•
Static - the motor shaft does not rotate during this test. The static test determines
only [IR Voltage Drop]. This test does not require the load to be uncoupled from
the motor.
The static and dynamic tests can be performed during the Start-up routine on the
LCD HIM. The tests can also be run manually by setting the value of the
[Autotune] parameter to 1 “Static Tune” or 2 “Rotate Tune”.
Alternate Methods for [IR Voltage Drop] & [Flux Current Ref]
If it is not possible or desirable to run the Autotune tests use one of the following
two methods:
•
When [Autotune] is set to 3 “Calculate”, any changes made by the user to motor
nameplate FLA, HP, Voltage, or Frequency activates a new calculation. This
calculation is based on a typical motor with those nameplate values.
•
If the stator resistance and flux current of the motor are known, voltage drop
across the stator resistance can be calculated. Then set [Autotune] to 0 “Ready”
and directly enter these values into the [Flux Current] and [IR Voltage Drop]
parameters.
Autotune Procedure for Flux Vector
For FVC vector control an accurate model of the motor must be used. For this
reason, the motor data must be entered and the autotune tests should be performed
with the connected motor.
Motor nameplate data must be entered into the following parameters for the
Autotune procedure to obtain accurate results:
•
[Motor NP Volts]
•
[Motor NP FLA]
•
[Motor NP Hertz]
•
[Motor NP RPM]
•
[Motor NP Power]
•
[Motor Poles]
Next the Dynamic or Static Autotune should be performed.