摘要
为了消除进气道喷射汽油机油膜动态效应对瞬态空燃比控制精度的影响,满足更严格的排放法规要求,提出一种新颖实用的长/短时油膜组合模型及瞬态油膜补偿策略,对加、减速时油膜变化进行快速准确补偿。通过油膜分配系数对长/短时油膜初始补偿量进行分配,根据衰减系数计算长/短时油膜实时补偿量并控制油膜补偿的作用时间。台架试验结果表明:该策略可以有效抑制瞬态空燃比偏移,最大动态偏差小于5%,稳定时间小于1s。
In order to eliminate the impact of dynamic effect of fuel film on the accuracy of controlling the transient air to fuel ratio(AFR)of a port fuel injection(PFI)gasoline engine to meet more stringent emissions requirements,a novel applicable fuel film compensation strategy as well as a fuel film model comprising of long-term and short-term fuel films is proposed to compensate fuel film variation rapidly and precisely under acceleration and deceleration conditions.The initial values of the long-term and short-term fuel films are calculated by distribution coefficients respectively.The real-time values of the long-term and short-term fuel films as well as their action time are controlled by decay coefficients.The results of engine bench test show that the proposed strategy effectively suppresses the deviation of transient AFR with a maximum error less than 5% and a stable time less than 1s.
引文
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