摘要
随着汽车制造技术的不断提升,新型汽车的发动机构造紧凑,导致汽车发动机点火线圈部分不易直接靠近,因而传统脉冲点火方式的汽车速度检测方法已无法满足现在的测量要求,通过理论分析发现,汽车发电机的转速和发动机的速度具有相关性,发电机输出的三相电压经过桥式整流,加在汽车蓄电池两端,而从汽车点烟器取出端电压信号的方式快捷简便、操作简单、安全。文中通过多级带通滤波电路实现了微弱电信号的噪声滤波,电压放大,最后采用快速离散傅里叶变换,完成了信号的实时频谱分析,从而可以得到汽车速度相关的频率信息,由此计算得到汽车发动机转速。
With the continuous upgrading of auto manufacturing technology,the new automobile engine is very compact in structure,which makes it difficult to directly approach the automobile engine ignition coil part,so the traditional vehicle speed detection through ignition pulse fails to meet the present measurement requirements.By theoretical analysis,the speed of automobile generator and engine are correlated,the output of the generator are three phase voltages,through a bridge rectifier connected to the vehicle battery,and getting the terminal voltage signal from the car cigarette lighter is a simple operation.Multistage band-pass filter circuit is used to realize weak electrical signal noise filtering and voltage amplification,after which the fast discrete Fourier transform is employed to realize real time signal spectral analysis to obtain the frequency related to the car speed for calculating the speed of automobile engine.
出处
《电子科技》
2012年第11期76-78,共3页
Electronic Science and Technology
