Operational　flexibility　of　thermal　power　plants　is　urgently　needed　to　maintain　balance　between　supply　and　demand　in　power　grids　with　high　penetration　of　intermittent　renewable　energy　generation.　A　new　coordinate　control　strategy　based　on　dynamic　simulations　was　proposed　and　evaluated　in　this　study　to　enhance　the　operational　flexibility　of　thermal　power　plants.　The　dynamic　simulation　model　of　the　control　object,　a　double-reheat　coal-fired　power　plant,　was　developed　and　validated.　The　operational　flexibility　of　the　power　plant　was　examined　using　the　original　control　strategy,　and　results　indicated　that　the　reheat　steam　is　seriously　overheated　when　the　power　ramp　rate　increases.　A　new　coordinated　control　strategy　assisted　by　high-pressure　extraction　steam　throttling　was　proposed　to　address　the　issue　of　reheat　steam　overtemperature　and　further　increase　the　power　ramp　rate.　The　proposed　control　strategy　obviously　improved　the　control　performance　of　thermal　parameters,　especially　the　reheat　steam　temperature.　The　change　magnitude　of　reheat　steam　temperature　decreases　by　3.0　degrees　C.　Moreover,　power　ramp　rate　increases　from　1.5%　to　4.5%　Pe0　min(-1),　which　significantly　enhances　the　operational　flexibility.　Furthermore,　the　proposed　control　strategy　is　compared　with　previous　ones　from　the　aspects　of　the　flexibility　and　efficiency.　(C)　2021　Elsevier　Ltd.　All　rights　reserved.