Methods and system for exhaust gas recirculation estimation via an exhaust oxygen sensor
US9920699B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 2016 |
| Grant date | Mar 20, 2018 |
| Priority date | — |
| Expiry date | Oct 19, 2036 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
Methods and systems are provided for estimating an amount of exhaust gas recirculation (EGR) from an exhaust passage into an intake passage of an engine system by operating an exhaust oxygen sensor in a variable voltage (VVs) mode. In one example, a method includes during operation of an exhaust oxygen sensor in the VVs mode where a reference voltage of the exhaust oxygen sensor is adjusted from a lower, first voltage to a higher, second voltage, adjusting engine operation based on the EGR amount estimated based on an output of the exhaust oxygen sensor and a learned correction factor based on the second voltage. In this way, the exhaust oxygen sensor may be used to correct for variations arising due to changing fuel composition and ambient humidity and further used to estimate the amount of EGR being recirculated in the system, thereby enhancing engine fueling and EGR control.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.