Can we control fan speed based on compressor demand?

edit

For EnergyPlus. We're modeling a sequence of operation which adjusts VAV fan speed based on the compressor load. Since this DX air handler cools AND dehumidifies to maintain a space humidity setpoint, the compressor demand is not proportional to the space cooling demand. ie, it can also be driven by dehumidification demand. I think some programming is required to model this. While I am not an EMS expert, it seems that the cooling demand is probably predicted based on the space cooling load - which does not "know" about the dehumidification demand.

Can someone share (at least conceptually) how I can go about determining the compressor total demand and then set fan speed proportionally to that demand?

Thanks very much.