Hot wire mass air flow sensor modeling and lag compensation

摘要

A nonlinear model for the hot wire mass air flow sensor (MAFS) was proposed, based on extensive experimental data. The MAFS time constant is found to vary strongly with air flow both magnitude and sense of magnitude. This results in different effective time constants for small signal applications and large signal applications. It was shown that lead compensation of the MAFS can provide improved transient air flow and air charge accuracy.