Control Structure Design for Oxy-Fired Circulating Fluidized Bed Boilers Using Self-Optimizing Control and Partial Relative Gain Analyses

摘要

Oxy combustion has been introduced in power plants for facilitated CO 2 capture and storage (CCS). Existing process controls for air-fired circulating fluidized bed (CFB) boilers are not necessarily optimal for oxy-firing. New degrees of freedom and alternative structures for control should be carefully analyzed for performance and flexibility. In this paper, the application of self-optimizing control (SOC) and partial relative gain (PRG) methods is presented for the early phases of control structure design. Controlled variable (CV) candidate sets are studied using the SOC concept. For the proposed CV sets, PRG analysis is used to reveal possible SISO loops with manipulated variables (MVs). Structures with promising results from both analyses were discovered.