Open AccessApplication of cascade PID plus feedforward in automatic denitration control
Author(s) -
Baoying Zhu,
Bing Li,
Zhen Wang,
Rongfang Song
Publication year - 2019
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1237/3/032015
Subject(s) - feed forward , control theory (sociology) , cascade , pid controller , overshoot (microwave communication) , nox , combustion , boiler (water heating) , control engineering , engineering , temperature control , computer science , chemistry , control (management) , waste management , chemical engineering , electrical engineering , organic chemistry , artificial intelligence
Generally, single PID loop plus feedforward control was adopted for the automatic denitration control in the power plant. When the ammonia pressure, unit load or NOx concentration of SCR inlet changes drastically, the adjustment control could not respond quickly, and the hysteresis is obvious. Based on the strategy of cascade PID plus feedforward control, a mathematical model for predicting the NOx concentration of the chimney inlet is constructed, which can reflect the boiler combustion conditions in real time. When the unit is in AGC-R mode, the feedforward control signals can be provided in time to adjust the ammonia injection flow, which can overcome the control problem caused by the characteristic of large hysteresis, and reduce the control overshoot and ammonia slip, and save the ammonia injection.