Optimal wide open throttle air/fuel ratio control
AssigneeVisteon Global Technologies, Inc.
InventorsGuoming G. Zhu, Chao F. Daniels
Life of this patent
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Abstract
This feature of the present invention comprises a method and apparatus which uses an ionization signal to optimize the air to fuel ratio AFR of the combustion mixture when the engine is operated at wide open throttle (WOT). This feature of the present invention optimizes the air to fuel ratio AFR on-line using the relationship between an air to fuel ratio AFR index CAFR and the air to fuel ratio AFR. In a preferred embodiment, the real-time control strategy adjusts the engine air to fuel ratio AFR based upon an air to fuel ratio AFR gradient parameter.
Claims20
A method of using an ionization signal to optimize the air to fuel ratio of a combustion mixture when an engine is operated at wide upon throttle, comprising:
- detecting an ionization signal, said ionization signal comprising a first peak, a valley and a second peak,
- determining a valley value related to a first voltage at said valley of said ionization signal,
- determining a second peak value related to a second voltage at said second peak of said ionization signal, and maximizing said second peak and said valley values.
An air to fuel ratio control system, comprising:
- an ionization detection circuit;
- a controller operably connected to said ionization detection circuit;
- memory operably connected to said controller;
- and
- software stored in said memory, wherein said software comprises instructions which use an ionization signal, said ionization signal comprising a first peak, a valley and a second peak, to optimize an air to fuel ratio of a combustion mixture, said instructions comprising the steps of:
- determining a valley value related to a first voltage at said valley of said ionization signal,
- determining a second peak value related to a second voltage at said second peak of said ionization signal,
- determining an air-to-fuel ratio index based on a combination of said valley value and said second peak value, and
- adjusting said air-to-fuel ratio of said engine based on said air-to-fuel ratio index.
A method of using an ionization signal to control an air-to-fuel ratio of an engine, comprising the steps of:
- detecting an ionization signal, wherein said ionization signal comprises a first peak, a valley and a second peak,
- determining a valley value related to a first voltage at said valley of said ionization signal,
- determining a second peak value related to a second voltage at said second peak of said ionization signal,
- determining an air-to-fuel ratio index based on a combination of said valley value and said second peak value, and
- adjusting said air-to-fuel ratio of said engine based on said air-to-fuel ratio index.
Dependencies are inferred from the claim text.