The wind farm that I created has 3 wind turbines E44 and according to the power curve, I was expecting that for high wind speeds the maximum output power of the wind farm would be 2730 kW (3 x 910 kW), according to the power curve of the wind turbine). But, instead, in the simulation results for the wind turbines it appears a Maximum Output of 2601 kW, which means that the wind farm never reaches its expected maximum capacity of 2730 kW. The same thing happens with a wind farm of 4 wind turbines E44. The maximum output result is 3468 kW instead of the expected 3640 kW.  Can you help me understand this?

HOMER scales the wind turbine power curve by the air density ratio, so if your altitude is above sea level the peak power output of the turbine can be less than the peak of the sea level power curve.  Scaling the power curve in this way is really only valid for stall-regulated wind turbines.