Nonlinear power-level control for MHTGRs by considering time-delay in helium temperature measurement

The Modular high temperature gas-cooled reactor is a very crucial type of small modular reactors (SMR) which has inherent safety feature, high thermal efficiency and satisfactory economic feasibility, and can be applied for both electricity and process heat production. Power-level control is a significant technique for guaranteeing the stable operation and load-following performance of the MHTGR. The sensors for measuring the inlet and outlet helium temperatures of an MHTGR are usually installed near the primary side of the corresponding steam generator, which must induces time-delay effect in the helium temperature measurement. Moreover, the signal transducing for the helium temperatures may also induce time-delay effect. Therefore, it is very meaningful to study the power-level control design method by considering the time-delay in measuring helium temperatures. In this paper, an output-feedback power-level control is proposed for the MHTGRs by using the delayed measurement of average helium temperature. A sufficient condition for this controller to be a globally asymptotic stabilizer is given. Numerical simulation results verify the theoretical results, and show the relationship between control performance and controller parameters.