The fast cut back(FCB) function is generally required in domestic export thermal power units

and in the FCB function design

it is necessary to consider the FCB situation of multiple units. By taking the Laos HongSa 3×626 MW coal-fired power station as an example

this article analyzes the FCB function control requirements and unit system configuration. According to the existing configuration of the power station

a control scheme was formulated for each unit to transfer to FCB mode independently

a method of judging electrical FCB was proposed

and the key control strategy was suggested in the unit FCB process. The unit's FCB test and actual operation of triggering the whole plant FCB proved that

the whole plant FCB control scheme and the unit's FCB control strategy are correct and effective. This brings huge safety and economic benefits to the power grid and power stations

and can be used as a reference for the FCB function design of large thermal power units.