空气预热燃烧系统空燃比闭环控制及其实验研究

Closed-loop Control and Research of the Air-fuel Ratio in the Air-preheating Combustion System

为了解决空气预热燃烧系统空燃比随预热空气温度发生偏移而导致的系统热效率降低等实际工程问题,通过对燃气汽车空燃比控制的研究,发现车用空燃比闭环控制器与锅炉等燃烧用闭环控制器的工作原理基本相同,但氧传感器电压信号存在差异,故根据实验结果对氧传感器电压信号进行修正后,将燃气汽车电控单元EDU改装到空气预热燃烧系统中。实验结果表明:改装后,在燃烧系统中,电控单元EDU能有效控制步进机动作,调节燃气流量,进而有效调节空燃比。

To solve the problems of low thermal efficiency caused by the air-fuel ratio of air-preheating combustion systems drifting as combustion-air-temperature change, the electronic control unit （ECU） of gas vehicles is adapted to the air-preheating combustion system by amending output signal from oxygen sensor. The results show that the ECU can effectively regulate the air-fuel ratio by controlling the stepping motor in combustion system.