How do you design coordinated control for a boiler-turbine-generator system?

Coordinated control balances energy demand with boiler capability for stable power generation. Control modes: boiler-following (turbine controls MW, boiler follows), turbine-following (boiler controls pressure, turbine follows), and coordinated (both respond to load demand simultaneously). Design elements: MW demand controller, pressure controller, fuel-air ratio control with O2 trim, feedwater control (three-element), and steam temperature control (desuperheater spray). Cross-limiting prevents fuel-rich or air-rich combustion. Runback logic handles constraints (mills, fans). Coordinate with automatic generation control (AGC) for grid frequency response. Implement extensive simulation before commissioning.