Patent · US Expired

Air-fuel ratio control system for internal combustion engine

US5390489A · kind A · utility

7Cited by
3References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 12, 1993
Grant dateFeb 21, 1995
Priority date
Expiry dateOct 12, 2013

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02D2041/1433
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An air-fuel ratio control system for an internal combustion engine uses a dynamic model which is set as an approximation to a controlled object. The controlled object covers an operation sequence from a fuel injection valve to an air-fuel ratio sensor which is provided downstream of a catalytic converter for detecting an actual air-fuel ratio based on the exhaust gas downstream of the catalytic converter. The system derives a fuel injection amount to be fed to the engine by performing a state-feedback control in such a manner as to control the actual air-fuel ratio to a target air-fuel ratio. The system performs the state-feedback control using, as state variables, current and past input and output data relative to the dynamic model. Accordingly, the actual air-fuel ratio monitored on the downstream-side of the catalytic converter is controlled to the target air-fuel ratio without delay by directly deriving the fuel injection amount using the state-feedback control.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.