FCB 08 Interpolated torque control

FCB 08 is used for cyclical torque setpoint input from a higher-level controller.

This higher-level controller usually calculates a track profile for several drive axes. The axis is then assigned just one setpoint (torque, torque limits, precontrol values, inertia) that it has to follow.

The inverter limits the setpoints using the application limits. The path curve profile is controlled by the controller.

The cycle in which the controller sends the setpoints to the axis does not usually correspond to the setpoint processing cycle of the inverter. If the inverter were to "see" the same controller setpoint for several cycles, a step-shaped actual torque value would result.

To prevent this from happening, the axis can calculate (interpolate) intermediate values if it knows the controller cycle. The inverter can be set to different cycle times of higher-level controllers.