Simulation on fuzzy control of steam temperature for a lignite-fired boiler

In this paper, a Fuzzy-PID model was established for a 600MW supercritical lignite-fired boiler through GSE software, of which the control effect was tested and compared with conventional PID control. The research result showed that when hot flue gas extracting percent stepped from 100% to 50%, the minimum of live steam temperature of Fuzzy-PID strategy was higher by 0.21℃ than conventional PID strategy, while the maximum of which was lower by 0.15℃, and the time of dynamic response reduced by 477s; Under the same condition, the minimum of reheat outlet steam temperature of Fuzzy-PID strategy was higher by 0.32℃ than conventional PID strategy, while the maximum of which was lower by 0.49℃, and the time of dynamic response reduced by 387s. It turned out that rapidity and stability of steam temperature adjustment under Fuzzy-PID control was better than conventional PID control, proving that this Fuzzy-PID strategy could improve the quality of common-used control system. The consequence had certain significance on power plant steam temperature control system optimization.