Will a power fan lift or disturb blown-in insulation?

If a power fan has been properly sized for the attic it will not disturb the attic insulation.

If the power fan is properly sized for the attic space (the right Cubic Feet of airflow per Minute for the attic square footage) and then is provided with the proper amount of intake (CFM of the fan divided by 300 = square feet of intake needed; multiply that number by 144 to convert to square inches), the disturbance of the blown-in insulation will be little.