Intake air flow rate measurement apparatus

摘要

An intake air flow rate measurement apparatus for measuring a flow rate of intake air taken in an internal combustion engine, using an electrothermal resistor type air flowmeter, includes a delay/non-linearity correction part to perform correction of an output signal of the electrothermal resistor type air flowmeter for a response delay and a non-linearity of the electrothermal resistor type air flowmeter; a waveform feature value extraction part to extract feature values of a waveform of an output signal which has been sent from said electrothermal resistor type air flowmeter and has been corrected for said response delay and non-linearity by the delay/non-linearity correction part; a back flow calculation part to obtain a back flow ratio based on the extracted waveform feature values; and a flow rate calculation part to obtain a correct flow rate of the intake air based on an output of the delay/non-linearity correction part and an output of the back flow ratio calculation part.