SHEN Qiankun, WU Hengyun, YANG Tao, et al. Optimization of analog control system and AGC for a supercritical 350 MW circulating fluidized bed unit[J]. Thermal power generation, 2020, 49(5): 126-131.
DOI:
SHEN Qiankun, WU Hengyun, YANG Tao, et al. Optimization of analog control system and AGC for a supercritical 350 MW circulating fluidized bed unit[J]. Thermal power generation, 2020, 49(5): 126-131. DOI: 10.19666/j.rlfd.202002039.
Optimization of analog control system and AGC for a supercritical 350 MW circulating fluidized bed unit
In unit 2 of Anhui Qianyingzi Power Generation Co.
Ltd.
before optimization on the analog control system
the main steam pressure deviation was large and the convergence of main steam pressure control was slow under steady-state condition. Meanwhile
the main steam temperature in the low and medium load section could not reach the rated temperature. Under variable load condition
the main steam pressure deviation was large and the feed water automatic tracking was poor. Under high load condition
due to the input of coal slime
the main parameters of the unit changed more violently
and the overpressure of the main steam pressure was serious
which affected the safe and stable operation of the unit. The whole process of the air and smoke system cannot be put into automatic mode
as a result
the load change rate of the unit was only 2 MW/min
which can not meet the relevant provisions of the power grid. In order to solve the problems existing in unit 2
the main analog control system of the unit was optimized. The water supply setting curve and the superheat setting curve of the intermediate point were modified. The oxygen control
primary air volume control and secondary air volume control strategies were modified. The variable load feed forward was increased
and the fuel volume
water supply flow and total air volume entering the furnace were dynamically coordinated. After optimization
the actual load change rate of unit 2 under AGC mode reached 5.25 MW/min
and the main parameters of the unit changed smoothly under steady-state and variable load conditions.