A study on the autoregulation systems of feedwater and differential pressure was made for NQ2 boiler in Qinling powerplant. Taking the two systems as one complete feedwater autoregulation system with full consideration of the correlationand interaction between the two regulation systems

a new boiler differential pressure regulation system has been designedwith selective control to automatically switch over between two feedwater pipes by means of software. And based on theregulation system of NQ1 boiler

a boiler feedwater regulation system is so designed that the flue gas oxygen content is usedas direct fuel and feed-forward signal and the steam enthalpy as the correction signal

so the feedwater will be varied following the heat load change.