Torque Feed-Forward Function - Omron XTRADRIVE User Manual

XtraDrive User Manual
The maximum speed of the servomotor will be used if Pn407 is set to a
value higher than the maximum speed of the servomotor.
External Speed Limit Function:
This function sets the voltage range for speed reference input V-REF
(CN1-5) according to the output range of the host controller or external
circuit.
When the default setting (600) is multiplied by 0.01V, the result (6V)
corresponds to the rated motor speed.
Parameter
Pn300
The default setting is 6V = the rated motor speed.
Principle of Speed Limit
When the control speed range is exceeded, the torque, which is
inversely proportional to the difference between the speed limit and the
actual speed, is fed back in order to return the system to a level within
the control speed range. In effect, the actual motor speed limit depends
on the load condition.
5.2.8.

Torque Feed-Forward Function

The torque feed-forward function is used only in speed control (analog
reference). This function is used to:
• Shorten positioning time
• Differentiate a speed reference at the host controller to generate a
torque feed-forward reference
• Input this reference together with the speed reference to the servo
amplifier
Too high a torque feed-forward value will result in an overshoot or an
undershoot. To prevent this, set the optimal value while closely
observing the system response.
Connect a speed reference signal to V-REF (CN1-5 and 6) and a torque
feed-forward reference signal to T-REF (CN1-9 and 10).
Signal
Speed Reference Setting Range: 150 to 3000
Input Gain Default Setting: 600
Motor
speed
5-40
Chapter 5: Parameter Settings and Functions
Setting
Speed limit
range
V-REF
Control Mode
Speed/Torque
Control