Energy balance control used for main steam temperature in power plant

A conventional controller based on feedback was designed based on the dynamic property of the object. The paper gives a method that is based on the energy balance in the main steam temperature control of the boiler. The energy of the steam obtained from gas in the superheater must be balanced under static and dynamic conditions. It involves all the properties and heat transfer coefficient calculations of the work medium including water, steam, gas and air. The formulas or equations are from engineering manuals. The method can calculate the flow rate of spray water according to energy balanced under static and dynamic conditions. The paper gives design methods and rules, and provides test results from a power plant simulator. The results show excellent stability and robustness compared with a traditional controller. The controller based on this method can be easily used by a DCS.