Closed-loop speed control

To enhance the accuracy of path speed, deviations from setpoints that are detected with a measuring wheel can be minimized by means of closed-loop speed control.

Closed-loop speed control is carried out with a PID controller. Deviations from setpoints can arise due to inaccuracies in diameter acquisition.

"Speed control" is activated by setting xActivateSpeedControl to "TRUE" (ST_Config_LineSpeed).

In operation, speed control is switched on when the start condition is fulfilled and the switch-on delay uiSwitchOnDelay (ST_Config_LineSpeed) has elapsed.

Speed control switches off if the actual value of the path speed is outside the specified uiTolerance (ST_Config_LineSpeed) for the duration of uiOutRangeTime (ST_Config_LineSpeed). The xErrorFeedbacksignal output variable is set.

The error is reset with the xResetErrorFeedbackSignal input signal. Speed control switches back on after the activation delay has elapsed. The xErrorFeedbacksignal output variable is reset.