干扰及偏置电压对火花塞检测信号影响的试验研究

Experimental Study on Influence of Interference and Bias Voltage on Detective Signal of Spark Plug

研究了在用火花塞作为传感器直接测量发动机燃烧状态的检测电路中 ,各种干扰以及电路中所加偏置电压对检测信号的影响。对由火花点火的高频信号和交流工频信号所产生的干扰进行了试验研究 ,提出了具体的解决措施和方案 ;另外在研究中还发现 ,当偏置电压不同时 ,通过火花塞所产生的离子电流的幅值和持续时间不同 ,在检测信号中出现单峰和双峰现象 ,由点火所产生的离子电流信号与偏置电压的值关系较大 ,而燃烧后期所产生的离子电流信号与缸内的压力温度有直接关系 ;通过对DA4 6 2 A型发动机的试验研究 ,获得了较为理想的火花塞检测电路和离子电流信号曲线 ,为用火花塞作为传感器实现汽油发动机缸内燃烧信号的检测奠定了试验研究基础。

Using a spark plug as a sensor to detect burning in the cylinder of I.C.E., the study into the influence of interference and bias voltage on detective signal has been carried out. some interference that will affct the ionic current through the spark plug,from the high frequency signal of spark and the lower frequency of working AC current,were tested,and the solving measures were presented. Furthermore the value and duration of the ionic current are different when the different bias voltagesare applied. Increasing the value of the bias voltage, the ionic current will change from single high apex to double apices. The relation between the ionic current signal from the spark and the bias voltage is rather great,but the ionic current signal from the later period of combustion directly relates to the pressure and temperature in the cylinder. The experiments have been down on the four-cylinder DA462-A engine, and the perfect spark plug detecting circuit and the curve of ionic current signal are obtained. These supply a test base for realizing using a spark plug as a sensor to detect the combustion signal in a gasoline engine.