Harvester fan speed control based on yield

A harvester having a harvesting structure for harvesting crop and a crop receptacle for receiving harvested crop, the harvester comprising:

• a crop conveying fan configured to operate at a fan speed to facilitate transfer of harvested crop from the harvesting structure to the crop receptacle by air;
• a control system for controlling the fan speed based on crop mass flow, the control system comprising:
• a crop mass flow feedback device for providing a crop mass flow feedback signal indicative of crop mass flow;
• and
• a controller in communication with the crop mass flow feedback device and configured to automatically lower the fan speed when the crop mass flow feedback signal indicates a lower crop mass flow and automatically raise the fan speed when the crop mass flow feedback signal indicates a higher crop mass flow;
• and
• a power module for supplying power to the crop conveying fan, the controller in communication with the power module and configured to decrease the power from the power module to lower the fan speed and increase the power from the power module to raise the fan speed.