Sigma-II Series SGM*H/SGDH USER'S MANUAL - Esco Drives ...

9 Adjustments9.4.2 Torque Feed-forward9.4.2 Torque Feed-forwardParameterMeaningPn002 n.0 Disabledn.2 Uses T-REF terminal for torque feed-forward input.Pn400Torque Reference Input GainSpeed Position TorqueSetting Range Setting Unit Factory Setting Setting Validation10 to 100(1.0 to 10.0V/Ratedtorque)0.1V/Rated torque 30 ImmediatelyThe torque feed-forward function is valid only in speed control (analog reference).The torque feed-forward function shortens positioning time, differentiates a speed reference at the host controller to generatea torque feed-forward reference, and inputs the torque feed-forward reference together with the speed reference to theSERVOPACK.Too high a torque feed-forward value will result in overshooting or undershooting. To prevent such troubles, set the optimumvalue while observing the system responsiveness.Connect a speed reference signal line to V-REF (CN1-5 and -6) and a torque forward-feed reference to T-REF (CN1-9 and-10) from the host controller.Host controllerSERVOPACKPositionreferenceT-REF (CN1-9)DifferentialK FFPn400Servomotor+ V-REF (CN1-5) ++ ++ Kp Pn300 Pn100 Current loop M-+-+Integration(Pn101)SpeedPGcalculationDividerEncoderKp: Position loop gainK FF : Feed-forward gainTorque feed-forward is set using the parameter Pn400.The factory setting is Pn400 = 30. If, for example, the torque feed-forward value is ±3V, then, the torque is limited to±100% of the rated torque.The torque feed-forward function cannot be used with torque limiting by analog voltage reference described in 8.9.3Torque Limiting Using an Analog Voltage Reference.9-16