FEEDBACK CONTROL PERMITS HEAVY EGR RATES

A new exhaust gas recirculation (EGR) control system has been developed to satisfY the needs of reducing NOx exhaust levels, providing smoothly changing EGR rates with varying operating conditions, and maintaining satisfactory vehicle driveability and fuel economy. Feedback control is used to ensure accurate control when heavy EGR is demanded. This control performance was obtained by comparing the venturi vacuum (a function of engine air intake flow rate) with pressure downstream from the EGR orifice (a function of EGR flow rate). Feedback valve control can compensate for changes in the characteristics of the EGR valve which result from long periods of operation. This is the basic theory of the venturi vacuum transducer (VVT) type EGR control system.

Media Info

  • Pagination: p. 44-47
  • Serial:
    • Automotive Engineering
    • Volume: 88
    • Issue Number: 6
    • Publisher: Society of Automotive Engineers
    • ISSN: 0098-2571

Subject/Index Terms

Filing Info

  • Accession Number: 00325060
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Report/Paper Numbers: HS-029 534
  • Files: TRIS
  • Created Date: May 21 1981 12:00AM