Research And Implementation Of Order Tracking Algorithm Based On NVH Test

In today's society,cars are getting more and more into their daily lives,because of the price difference,its performance is naturally different,not knowing that about one-third of the car's fault is related to NVH,and the major companies have 20%of the R&D costs are consumed in the solution to NVH issues,some high-end cars in the research and development process,for NVH test investment is particularly large.Car NVH performance has been more and more people pay attention.NVH,simply is the noise,vibration and sound roughness(Noise,Vibration,Harshness)of the English abbreviation.In recent years,due to the gradual popularization of NVH research,people's attention to eco-environmental protection and self-health has become stronger,and the research on NVH test is imminent.This paper only focuses on the vibration from the point of view of vibration.The tracking algorithm further helps solve the problems encountered in the NVH test.As we know,the car contains a large number of rotating parts,such as gearbox,engine,etc.,and these components in operation will produce a lot of noise,noise is derived from vibration,so the noise problem in the car can be extended to Solve the vibration problem of rotating machinery.Order tracking technology is an important technology to solve this problem,the advantage is that you can make full use of the machine speed information analysis of the rotating machinery in the fault.Rotating machinery in the rise and fall speed and other changes in the process of vibration signal is not a smooth signal,coupled with the impact of the surrounding environment,the signal content is intricate,if the simple use of the traditional FFT method is clearly unable to effectively analyze the signal content,More easily because of the various parts of the band aliasing,resulting in "frequency fuzzy" phenomenon.This paper focuses on the tracking of this new signal analysis technology to start.The accurate calculation of speed is one of the key technologies in order tracking.This paper introduces a speed calculation method based on first order digital differential and single pulse segmentation interpolation.In this method,the initial rotation speed is obtained by calculating the initial rotation speed of the first order digital differential,the speed of each sampling time is obtained,and the correspondence between the vibration and the speed is established,which is done for the follow-up order tracking study.Based on the actual production and life,this paper puts forward and implements the computational order tracking technology based on engineering experience.The method is fast and easy to calculate,and the accuracy is also satisfied.In addition,taking into account the current market has been expensive vibration analysis equipment,many domestic small and medium enterprises,although the demand but it is difficult to bear the high cost,we put forward new ideas and new ideas,research and development of portable NVH vibration analyzer.The instrument is composed of vibration sensor,speed sensor,signal conditioner,industrial computer as the main body,plus a set of analysis software,the software part is the use of VC ++ 6.0 development completed,which contains the basic operation interface,algorithm implementation,the results Display and so on.In order to verify the feasibility of the instrument,we also assembled a demo motor,which with the detection.The results of field measurement show that the step tracking method mentioned in this paper is feasible.The vibration analyzer is small in size,full and inexpensive.It has a strong practical value and is expected to be pushed after the follow-up.market.