Integrated control and process design for improved load changes in fluidized bed boiler steam path

Integrated control and process design is considered for a power plant to obtain improved load changes in output electrical power (MWe). Fast load transitions are increasingly needed in conventional power plants, which calls for a deeper integration between the boiler and its control system. An integrated design methodology is applied to an industrial boiler steam path in this paper; no past reports of such an application exist in the literature. The methodology utilizes dynamic optimization together with performance relative gain array and closed-loop disturbance gain controllability analysis. The aim is to optimize the boiler steam storage distribution, the turbine valve operation, and the electrical power and main steam pressure controllers during different MWe ramp reference trajectories. The methodology was successful in defining closed-loop designs with excellent MWe setpoint tracking, small steam pressure disturbances and minimal steam throttling. The results also highlighted the challenges related to integrated design in power plants. (C) 2019 Elsevier Ltd. All rights reserved.