Control Strategy Research of a Selective Catalytic Reduction System for Heavy-Duty Application

doi:10.1007/s12204-017-1866-9

Abstract

Abstract: An AdBlue dosing control strategy of the selective catalytic reduction (SCR) system is developed for a heavy-duty diesel (HDD) engine. The strategy includes a raw emission prediction model, an ammonia (NH3) coverage prediction model, a transient heat hysteresis correction algorithm, an NH3 leakage control model for transient operation conditions, and a feedback controller (FBC). FBC has been developed by using mathematical manipulation to change output signal of sensor based on cross-sensitivity of nitrogen oxide (NOx) sensor to NH3. The quantification of control parameters is based on experiments and Nyquist stability criterion. FBC is enabled in most test conditions to satisfy the stability requirements. NOx conversion (DeNOx) efficiency of SCR system is 82.4% in European steady-state cycle (ESC) test and 80.3% in European transient cycle (ETC) test, while the leakage of NH3 is under 10?5 volume fraction in average.

Key words: selective catalytic reduction (SCR)| NOx conversion (DeNOx) efficiency| control strategy| feedback control| model

摘要： An AdBlue dosing control strategy of the selective catalytic reduction (SCR) system is developed for a heavy-duty diesel (HDD) engine. The strategy includes a raw emission prediction model, an ammonia (NH3) coverage prediction model, a transient heat hysteresis correction algorithm, an NH3 leakage control model for transient operation conditions, and a feedback controller (FBC). FBC has been developed by using mathematical manipulation to change output signal of sensor based on cross-sensitivity of nitrogen oxide (NOx) sensor to NH3. The quantification of control parameters is based on experiments and Nyquist stability criterion. FBC is enabled in most test conditions to satisfy the stability requirements. NOx conversion (DeNOx) efficiency of SCR system is 82.4% in European steady-state cycle (ESC) test and 80.3% in European transient cycle (ETC) test, while the leakage of NH3 is under 10?5 volume fraction in average.

关键词: selective catalytic reduction (SCR)| NOx conversion (DeNOx) efficiency| control strategy| feedback control| model

CLC Number:

TK 421.5

WANG Tiantian1 (王天田), LIN Feng1* (林峰), HU Jie1 (胡杰),KE Yuqiang2 (柯于强), ZHANG Yueqiu3 (张岳秋). Control Strategy Research of a Selective Catalytic Reduction System for Heavy-Duty Application[J]. Journal of shanghai Jiaotong University (Science), 2017, 22(5): 577-588.

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