一种实现组合燃烧模式闭环控制的宽域氧传感器控制器

为了降低重型增压燃气发动机燃料消耗和热负荷,并使之运行在稀薄燃烧区,设计了一种宽域氧(UEGO)传感器控制器和基于此控制器快速实现稀薄燃烧控制的方法。该控制器通过采集UEGO、发动机转速和进气压力等信号,精确计算得到当前工况下的空燃比值,并与可标定的目标空燃比值进行比较,判断当前混合气的浓稀状态,向基于理论空燃比控制的燃气发动机ECU实时输出模拟的开关型氧传感器信号。试验表明:控制器结合基于理论空燃比控制的ECU能实现燃气发动机理论空燃比燃烧和稀薄燃烧组合模式的闭环控制。

UEGO Sensor Controller for Close Loop Control of Compound Combustion

To reduce the fuel consumption and thermal load of heavy duty turbocharged CNG engine and make the engine work in the learn-burn area,the UEGO sensor controller was designed.Based on the controller,the rapid lean-burn control was realized. The controller recorded the signals of UEGO,engine speed and intake pressure and then calculated.The air-fuel ratio for current condition was acquired and compared with the target air-fuel ratio and then the state of current mixture could be judged and converted into the electrical signal.Finally,the simulated switch-type oxygen signal was written into CNG engine ECU with stoichiometric air-fuel ratio in real time.The results show that the controller can realize the close loop control of CNG engine stoichiometric combustion and lean-burn combustion based on the ECU of stoichiometric air-fuel ratio control.