Lenze 9400 - Manual (Page 149)

Lenze · Servo-Inverter 9400 HighLine · Reference manual · DMS 10.0 EN · 11/2013 · TD05/06
149
5 Motor interface
5.4 Servo control (SC)
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Setting of actual speed filter
In order to maximise the dynamics of the speed control loop, the actual speed filter should be
operated with a time constant as low as possible ( C00497 ). The lower the time constant the higher
the gain of the speed controller. Since actual value filters have the task to dampen measuring errors
or interference components, it must be found a compromise between filter task and the resulting
delay.
If a Lenze motor is selected from the motor catalogue, a time constant is automatically preset in
C00497 which serves to operate the motor even with a faulty detection (e.g. in case of a bad shield
connection).
When using EMC-compliant systems or high-quality encoders, you can reduce the preset time
constant considerably. For this purpose, the running noise of the motor can be used for setting
C00497 at constant speed.
If this is not possible, e.g. due to a too loud environment or because the motor is too far away, the
noise of the actual speed value or the setpoint torque value can be used for evaluation by means of
the Oscilloscope . Please observe that the speed controller gain Vp ( C00070 ) in is used for the torque
setpoint.
Dynamics of the actual value detection
Another element which influences the maximally achievable control dynamics, is the dynamics of
the actual value detection itself. In case of optical encoders, the time delay by the actual value
detection does not need to be considered. This does not apply to resolvers.
The resolver evaluation of the controller is adapted to the resolver types mounted in Lenze motors
and offers a good compromise between the dynamic performance and interference suppression. If
the resolver is used as a speed feedback system, the dynamic performance of the resolver evaluation
determines, among other things, the maximum speed controller gain by means of which stable
operation is possible.
From software version V5.0 onwards, it is possible to increase the dynamics of the resolver
evaluation in C00417 in an EMC-compliant system (with low interference) without a quality loss in
the speed signal.
 Adaptation of the resolver evaluation dynamics ( 250)