5 optimising response to setpoint changes, Optimising response to setpoint changes, 5motor interface – Lenze 9400 User Manual
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5
Motor interface
5.4
Servo control (SC)
154
Lenze · Servo-Inverter 9400 HighLine · Reference manual · DMS 10.0 EN · 11/2013 · TD05/06
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5.4.1.5
Optimising response to setpoint changes
Setting the load moment of inertia under
does not always provide the optimum torque
feedforward control. Depending on the application, an adjustment of the setting under
may be necessary to optimise the response to position/speed setpoint changes by means of the
torque feedforward control.
[5-4]
Typical signal characteristics for different settings of the load moment of inertia
Apart from the load moment of inertia, effects can be compensated with
, which in the
closed speed control loop are identified by the speed controller. These for example include the
friction torques.
Below you will find a description of a procedure for optimising the feedforward control behaviour
starting from the system's moment of inertia.
Without feedforward control:
set too low:
set too high:
Optimum feedforward control:
Speed setpoint (Speed.dnSpeedSetpoint signal)
Actual speed value (Speed.dnActualMotorSpeed signal)
Speed controller output (Torque.dnOutputSpeedCtrl signal)
Torque feedforward control (Torque.dnTotalTorqueAdd signal)
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