Abstract

Mass air flow sensors are increasingly used in the automotive industry to measure the mass air flow intake into the internal combustion engine. A problem occurred with the basic circuit for bridge type mass air flow sensor is the measurement accuracy of the sensor is affected by the temperature variation in the air. This paper presents the development of an open loop Fuzzy Temperature Compensation Scheme (FTCS) for hot wire mass air flow sensor.  In order to verify the performance of the proposed scheme, first a simulation model was developed using Matlab/Simulink. Then, based on the Matlab/Simulink simulation, the FTCS has been implemented in hardware based real-time using Digital Signal Controllers, (dsPIC) with the Programming C Language.  The effectiveness of the proposed fuzzy compensation scheme was verified with the estimation error within only 1% over the full-scale value.

Key words: Hot wire, mass air flow sensor, temperature compensation, fuzzy logic.