Engine error detection system
AssigneeTula Technology, Inc.
InventorsShikui Kevin CHEN, Masaki NAGASHIMA, Li-Chun CHIEN
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Abstract
A variety of methods and arrangements for detecting misfire and other engine-related errors are described. In one aspect, a window is assigned to a target firing opportunity for a target working chamber. There is an attempt to fire a target working chamber during the target firing opportunity. A change in an engine parameter (e.g., crankshaft angular acceleration) is measured during the window. A model (e.g., a pressure model) is used to help determine an expected change in the engine parameter during the target firing opportunity. Based on a comparison of the expected change and the measured change in the engine parameter, a determination is made as to whether an engine error (e.g., misfire) has occurred.
Claims29
A method for detecting misfire in an engine, the engine having a plurality of working chambers and being operated in a skip fire manner, the method comprising:
- assigning a window to a target firing opportunity;
- attempting to fire a target working chamber during the target firing opportunity;
- measuring a change in an engine parameter during the target firing opportunity;
- using a multi-cylinder pressure model to help determine an expected change in the engine parameter during the target firing opportunity wherein the pressure model involves estimating pressure in a skipped working chamber;
- and
- based on a comparison between the expected change and the measured change, determining whether the target working chamber misfired.
A misfire detection system for determining whether a particular working chamber in an engine has misfired, the engine being operated in a skip fire manner, the misfire detection system comprising:
- an engine parameter measurement module that is arranged to:
- assign a window to a target firing opportunity;
- and
- measure a change in an engine parameter during the target firing opportunity;
- and
- a misfire detection module that is arranged to:
- use a pressure model to help determine an expected change in the engine parameter during the target firing opportunity wherein the pressure model involves estimating pressure in a skipped working chamber;
- and
- determine whether the target working chamber misfired based on a comparison between the expected change and the measured change.
A method for using an adaptive model to estimate a change in an engine parameter, the method comprising:
- assigning a window to a first target firing opportunity;
- attempting to fire a target working chamber during the first target firing opportunity;
- measuring a first change in an engine parameter during the first target firing opportunity;
- using a model to help estimate a first expected change in the engine parameter during the first target firing opportunity wherein there is an offset between the first expected change and the first measured change;
- and
- based on the measured first change in the engine parameter, adjusting the model to help reduce the offset.
Dependencies are inferred from the claim text.