Research On Detection Algorithm Of Vortex Axis-6 Compressor Instability Signal

Aircraft engine,as the core device of the aircraft,its quality has a direct impact on the overall performance of the aircraft.Therefore,researches on the aircraft engine techniques to improve the engine performance are of great significance of to the national defense aviation and civil aviation services.The turbo engine,as a member of the aero engine family,is widely used in helicopter but also has the engine instability problem.While the compressor instability is the main manifestation of aero engine instability,many researchers conduct study on the compressor instability to find out the instability is caused by the spread of numbers of uncontrollable mass,whose mainly presence is uncontrollable rotation and surge,and the two aspects are related.The surge is usually caused by the uncontrollable rotation of the mass,but also cases that the engine directly surges.The instability of the engine limits the effectiveness of the engine as well as harms the internal structure of the engine so that threatens the safety of the helicopter.To initiatively control the compressor,researches are conducted on the signals of the compressor instability and many algorithms are raised to detect the instable signal.The detect algorithm usually regards the compressors pressure signal as the research object.By extracting the features of the threat signal,appropriate algorithms are raised to predict and control the state of the compressor.The mathematic model of the compressor is a series of functions that describe the variation of each variable.The mathematic model is also the most important tool to analyze the compressor instability.This article proposes an improvement based on the MG model and deduces a model toanalyze the compressor instability problem.A simulation verification is conducted in this article based on the SIMULINK and the results show that the model can better describes the compressor instability.Considering the actual measured signal is full of noise signal,so this article by comparing selected wavelet threshold de-noising method to deal with the noise data are used to test bench.Then based on the research of the classical function,this paper proposes a new threshold function is used to estimate the wavelet threshold,and introduces two existing improvement function,de-noising simulation experiment,and then compare the performance difference,the final results show that the threshold function is proposed in this article have better effect.The key point of the compressor instability signal detection is the detection algorithm.In this paper,we select the experimental data of the bench test of the compressor provided by a research institute.First of all,through the study to determine the choice of the first level of static pressure signal as a research object,and then detailed study of the HHT-based method and the correlation coefficient based on the compressor instability in the application of detection.The results show that the two methods can effectively detect the stall signal.In summary,this article describes the compressor instability signal detection algorithm can achieve a flexible engine instability detection,and can monitor the engine running.The simulation results show that the algorithm can detect the precursors of instability and predict the precursors of instability.