Fuel distributor control of an internal combustion engine using Hilbert-Huang transformation

Abstract

Article purpose: to consider the possibility of Hilbert-Huang transformation (HHT) use for vibration-acoustic control of a fuel dispenser operation in an internal combustion engine HHT was proposed by Norden Huang in 1995 to study the surface waves of typhoons. In recent years, the method has been actively used in geophysics, medicine, radio engineering, etc. Hilbert-Huang transformation makes it possible to extract information from signals about the rapid temporal changes of their spectral composition. HHT is the method of empirical mode decomposition of signals and Hilbert spectral analysis.

The article presents the results of vibration-acoustic signal processing of an internal combustion engine using HHT. The series of experiments was carried out in a test laboratory on a motorized bench (eight-cylinder two-stroke engine). The measurements of vibrationacoustic signals were carried out for the periods when the engine operates in normal mode and when one of the cylinders is not working (the supply to the fuel dispenser is switched off). It was determined that the 9th empirical mode (Intrinsic mode functions) contains the basic harmonic components of a signal. When the fuel dispenser of one of the cylinders is disconnected, the asymmetry of the instantaneous frequencies distribution of the 9th IMF appears relative to their average value. During the analysis of their central third-order moment, it is possible to establish the state of the controlled object properly.

Keywords: Hilbert-Huang transformation, empirical mode decomposition by ensemble, instantaneous frequency, third-order central moment, nondestructive testing, internal combustion engine, vibration-acoustic signal