In datahub settings, what is the "Feed-in Buffer” function used for?

“Feed-in Buffer” is divided into 4 gears:“Disable”,“Low”, “Mid”, “High”
The representative threshold values for each gear are respectively: 1%, 2.5%, 4.5% and 6.5%.
The definition of those threshold values is:
1. Except for “Disable”, when the load in other 3 gears is stable, taking power firom the grid [the total power of grid-connected inverter * threshold value] is preferred;, In the “Disable” gear, when the load is stable, the output power of grid-connected inverter ranges fiom [taking 1% of power] to [selling 1% of power]. [Selling 0% of
power] cannot be guaranteed, but less power will be taken from the grid.
2. When the load fluctuates within the range of [the total power of grid-connected inverter * threshold value], the power of grid-connected inverter will not drop to 0 directly; Otherwise, the power of grid-connected inverter will drop to 0 immediately and then the power will increase slowly.