Included is a combine having a feeder housing for receiving harvested crop, a separating system for threshing the harvested crop to separate grain from residue, a crop cleaning system including a cleaning fan powered by a fan drive to propel the residue into a residue system of the combine, at least one sensor for detecting an operational parameter of the fan drive, and a controller coupled to the at least one sensor. The controller is configured to determine a load on the fan drive from the detected operational parameter, compare the determined load to a load threshold, and control a speed of the cleaning fan based on the comparison.
