Modeling, simulation, and control of multi-fuel once-through boilers

Starting with an overview of the present situation and future developments in electricity production in the Netherlands, the problem of fast and accurate control of large coal-fired power stations is posed. The origin of this problem is the unavoidable and the increasing participation of coal-fired boilers in the short-term load frequency control of the national grid. From this problem formulation stems the desire for an accurate and detailed dynamic model of a complete coal-fired electricity generating plant, targeted at evaluation of the performance of control schemes. Such a simulation model is not freely available and has therefore been developed. An overview of this model is presented and several details, e.g., the modeling of the water/steam flow in the steam generator and the temperature and heat flux modeling in the furnace, are highlighted. The model is used to verify whether a proposed control concept meets: (1) the specifications set forth by the Dutch electricity generating board; and (2) additional technological considerations. It appears that the simulation model can fulfil its intended role and that the proposed control scheme is suitable for its task