Model predictive control of once through steam generator steam quality

Abstract

Steam quality is a critical process variable in the once through steam generator (OTSG) operation. However, the lack of online measurement and closed loop control of steam quality limits the efficient operation of OTSGs. To resolve this problem, this paper presents a model predictive control (MPC) solution based on soft sensor measurement for OTSG steam quality. Bad status handling strategy is outlined to ensure reliable estimation and control results. Instrumentation reliability issue is also considered in the MPC design. Successful application results have demonstrated effectiveness of the developed control strategy.