CLOSED LOOP CONTROL OF LEAN FUEL-AIR RATIOS USING A TEMPERATURE COMPENSATED ZIRCONIA OXYGEN SENSOR

This paper investigates closed loop control of fuel-air ratio using a temperature compensated zirconia sensor at other than stoichiometric conditions. Assuming lean combustion and using the Nerst equation for the oxygen sensor, equations are derived relating equivalence ratio to the oxygen sensor output voltage and temperature. Equations are also derived and discussed which give the sensitivity of predicted equivalence ratio to measurement errors in voltage and temperature and to variations in humidity and exhaust pressure. A simplified calculations scheme, which involves a linearization in equivalence ratio and which might be used in an onboard computer, is presented and its accuracy is discussed. /GMRL/

• Corporate Authors:

  Society of Automotive Engineers (SAE)

  400 Commonwealth Drive
  Warrendale, PA  United States  15096
• Authors:
  • HUBBARD, M
  • Bonilla, J J
• Publication Date: 1976-2

Media Info

• Pagination: 12 p.

Subject/Index Terms

• TRT Terms: Combustion; Computers; Exhaust gases; Fuel air mixtures; Humidity; Lean fuel mixtures; Oxygen; Stoichiometry; Zirconium
• Old TRIS Terms: Lean fuel engine
• Subject Areas: Highways; Safety and Human Factors;

Filing Info

• Accession Number: 00142394
• Record Type: Publication
• Report/Paper Numbers: SAE #760287
• Files: TRIS
• Created Date: Apr 13 1977 12:00AM