Method of monitoring in-use performance ratios of onboard diagnostic systems for plug-in hybrid electric vehicles
US8346424B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 2010 |
| Grant date | Jan 1, 2013 |
| Priority date | — |
| Expiry date | Jul 9, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T90/14
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A method of monitoring an onboard diagnostic system for a plug-in hybrid electric vehicle includes incrementing the denominator of an N/D ratio for the onboard diagnostic system only when a total time criteria, a vehicle speed criteria and an idle criteria are satisfied after an internal combustion engine of the vehicle has been fueled. The diagnostic system performance is summarized into a single N/D ratio. When an underperforming ratio is identified, the system controls the engine to provide more engine operation and subsequent diagnostic observability. The denominator of the N/D ratio is compared to a verification denominator to identify vehicles that are typically operated in a manner such that an engine-on cycle does not begin, or is not identified, until very near the end of the drive cycle, thereby preventing the denominator and a numerator of the N/D ratio from incrementing, and thereby providing a false passing performance ratio.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.