Analysis of the time-frequency characteristics of internal combustion engine vibration signal based on adaptive generalized S transform

摘要

An adaptive generalized S transform algorithm with an optimization parameter was first proposed in this paper. A simulation experiment was subsequently designed to verify the validity of the algorithm. Compared with other time-frequency analysis algorithms, this algorithm has a higher resolution and energy concentration, and is more suitable for analyzing the time-frequency characteristics of the cylinder head vibration signal. Afterwards, various time-frequency analysis methods were adopted to analyze the vibration characteristics of a four cylinder gasoline engine. The results show that the vibration energy of the cylinder head is chiefly concentrated in the frequency band of 1700∼2300Hz, and mainly caused by the engine combustion incentive. The lower frequency components of 37Hz and 74Hz correspond to the fundamental frequency and its second-order harmonic respectively. The analysis results are helpful to the vibration control and structure optimization of IC engine.