Fuel consumption monitoring system using control signal and characteristic correlations of fuel injector

Abstract

Objectives of this study are (i) to investigate characteristics of a fuel injector and to establish the characteristic correlation for correcting the fuel injection rate calculated from the control signal of a fuel injector, and (ii) to design and fabricate the fuel consumption monitoring system by measuring the control signal of fuel injector in conjunction with considering the obtained characteristic correlation to enhance accuracy of the measured fuel consumption rate. The characteristics of a fuel injector (maximum fuel injection rate of 270 cm3/min), e.g., engine speeds, percentages of injector’s duty cycle, and pressure differences between fuel rail and intake manifold, were experimentally investigated on a test set in the laboratory. The study found that when the engine speed increased, the fuel injection rate increased. When the percentages of infector’s duty cycle increased, the increasing ratio was less than the one-to-one increasing ratio as a case of the ideal. Moreover, when the pressure difference increased, the fuel injection rate increased. After that, the fuel consumption monitoring system was designed and fabricated based on the Arduino Mega 2560 microcontroller. Trip distance was measured by a GPS module. The real-time fuel consumption rate could be shown on a LCD display. All recorded data were stored onto a SD card for further data analysis. Finally, the on-road-test validation was conducted by on the 2011 Mitsubishi Triton installed with the 4-cylinder gasoline engine with total displacement of 2,351 cm3. It was found from that the average discrepancy of the measured fuel volume was ± 1.88% compared to the actual fuel volume obtained by measuring a decreasing volume of consumed fuel.