MPH-02, MPB-02, MPD-02
Application-Related Aspect
Method
Synchronous Motors with
Absolute Measuring System
Sequence of the Saturation
Method for Synchronous Motors
with Absolute Measuring System
DOK-INDRV*-MP*-02VRS**-FK01-EN-P
• C1215 Command only possible in 'bb'
• C1216 Commutation determination not selected
• C1222 Error when writing offset parameters
Determining the Commutation Offset, Saturation Method
The saturation method for determining the commutation offset can be
used for all types of synchronous motors. Compared to the measuring
method, it provides the advantage that distance measurement is not
required. Stator and rotor of the motor in this case can be inaccessibly
installed in the machine. The commutation offset is determined by a
current flow procedure. The controller sets drive enable automatically for
the duration of the measurement.
Note:
Observe the restrictions for the saturation method (see table
above "Restrictions for saturation method")!
By a sinusoidal test signal the voltage and frequency of which requires
motor-specific settings (P-0-0506, Amplitude for angle acquisition,
P-0-0507, Test frequency for angle acquisition), the controller
determines the commutation offset of the synchronous motor. It is
therefor necessary that the generated test current causes magnetic
saturation effects in the motor.
The motor-specific setting of voltage and frequency of the test current is
carried out automatically when the value "0" has been entered in
P-0-0506 at the start of P-0-0524, C1200 Commutation offset setting
command. The detected motor-specific value for P-0-0506 is stored and
used for commutation setting for further operations.
Note:
If the test current does not cause any magnetic saturation
effect in the motor, the command C1200 can only be used for
commutation setting with restrictions.
→ If the maximum current of the controller is not sufficient in
order to cause magnetic saturation in the motor (e.g. in the
case of command error C1218), use controller with higher
type current!
→ If the generated test current is too low in spite of sufficient
controller type current (e.g. in the case of command error
C1218), measures as described for C1218 in the
Troubleshooting Guide can be carried out!
Should it be impossible to determine a commutation angle in
spite of these measures (e.g. command error C1221), the
saturation method cannot be used for commutation setting!
Carrying Out the Saturation Method (Commissioning)
In the case of synchronous kit motors with absolute measuring system,
the saturation method is only started by a command at the initial
commissioning and the determined commutation offset value is stored in
the controller or in the encoder data memory. In addition, the value can be
manually optimized during the initial commissioning.
1. In P-0-0522, Commutation setting control word activate:
initial commissioning mode and
saturation method
6-27
Drive Control