Research On System Of Condition Monitoring And Fault Diagnosis For Diesel Engine Using DSP

Due to many components and complex structure, especially it usual works at bad condition. In order to assure reliability and security of diesel, it is important for diesel engine to monitoring running state and fault diagnosis on-line.The instantaneous speed signal contains rich diesel engine working information, which can directly show the working status of the diesel engine cylinder. In this paper, fault diagnosis technology for diesel engine cylinder is developed basing on instantaneous speed signal. Hardware circuit with TMS320F2812DSP high-speed processing chip is designed. which can realized instantaneous speed acquisition, signal processing and running state analysis of diesel engine. And single cylinder misfire fault is judged by polar coordinates method.The instantaneous speed signal is analyzed respectively by means of FFT and polar coordinate for studying the cylinder fault diagnosing system in a deep-going way. By comparing the two results, the polar coordinate system can not only diagnose out the cylinder internal failure timely, but also can positioning fault cylinder more quickly.The circuits of instantaneous speed and TDC, CAN is designed A PC monitoring system based on the LAB VIEW is designed basing on the DSP according to the requirement of the fault diagnosing system. The corresponding programs are also designed. In order to monitor the diesel engine fault state by a intuitive way. The monitoring system can instantly display the diesel engine instantaneous speed curve, polar monitoring status and the uniformity state of each working cylinder by using the CAN.At last, we verified the above cylinder fault diagnosing system in laboratory on the diesel of C4108ZC53, the result shows that the method of polar coordinate is very effective in diagnosing and positioning the cylinder fault of diesel engine.