Research On Ignition Coils Discharge Pulse Test Method

The ignition coil is the core component of automobile ignition system, theperformance of Ignition coil influences the vehicle dynamic indicators and fuelconsumption，and discharge of pollutants. Insulation fault is one most severe faultfor ignition coil, it is usually associated with partial discharge phenomenon,whichhas the characteristics of randomness and high frequency oscillation and magnitudeof mutation.At the present stage there isn’t blameless ignition coil testing means, theordinary ignition coil test equipment can not collect high-frequency pulse signaleffectively. People mainly rely on artificial means. Therefore developing testsystem which could be able to automatic test of the ignition coil discharge pulsesignal has great significance.This paper builds simulation ignition system based on the feature of theignition coil. Programs data collection procedures with LABVIEW.Collectingsignal by RIGOL DS1052E oscilloscope. Simulation of the ignition coil systemworking environment.According to the characteristic of discharge pulse of the timedomain, frequency domain and time-frequency joint domain, Research Methods toeliminate the noise and the discharge pulse detection and achieveit, to prepare forthe subsequent processing.This paper serves a variety of models ignition coi as the object of study. By thecomputer USB interface to remotely control oscilloscope. Select the appropriateparameters. Show the waveform of the ignition coil primary current signal and thesecondary voltage signal acquisition and waveform data to the computer.According to the type of noise in the work environment of the ignition coil,selecting the adaptive, wavelet threshold and wavelet packet entropy thresholdmethod. Based on the existing theory, this paper contrasts different wavelet basis byexperiment. Choose the best wavelet threshold algorithm parameters. Then comparethe effect of three methods. Eventually obtained in this paper, wavelet packetentropy threshold denoising method can achieve the best denoising, for subsequentidentification and testing of the discharge pulse signal.According to the characteristics of the denoised signal，this paper developsthe wavelet time-frequency analysis methods and high-pass filtering method,achieve the detection and measurement of the discharge pulse.Finally, this paper designs experiment, using the above method, a variety of different models of the ignition coil to discharge detection. Based artificial testresults, this paper verifies the effect of the two methods of detection, and comparesthe advantages and disadvantages of the two methods.The ignition coil discharge detection system can automate the data acquisition,signal de-noising, detection and testing. Lay the foundation for further study of theignition coil discharge detection.