基于状态观测器的电喷汽油机进气流量精确估计

A Precise Estimation of Intake Port Air Mass Flow in SI Engines Based on State-Observer

在对进气管空气流量动态特性进行建模、参数辨识的基础上构建了稳态及瞬态进气状态观测器,用以对进气流量进行精确估计。MATLAB/Wave联合仿真结果表明,所构建的观测器能够准确及时地跟随实际进气量变化,进气压力观测值最大误差不超过±3 kPa,每循环进气量观测值最大误差不超过±0.01 g。将观测器应用于实际ECU控制器中,台架试验结果表明,空燃比控制误差稳态时保持在±3%以内,瞬态时保持在±6%以内,满足空燃比精确控制要求。

An intake air mass flow mean value model was proposed in order to precisely estimate the intake air mass flow using intake air state-observers both in transient and steady operating conditions. The simulated result of MATLAB/Wave shows that the observers can always track the intake air status precisely and promptly, the maximum estimation error of intake manifold pressure is less than ±3 kPa, while for the intake port air mass per cycle it is less than ±0.01 g. The observers were embedded in the ECU and were tested on an engine. The result shows that the maximum error of air fuel ratio control is less than ±3% in steady operating conditions, and ±6% in transient operating conditions. The observers can always meet the requirement of accurate air fuel ratio control.