The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 13, 2008
Filed:
Mar. 02, 2006
Load transient control methods for direct-injection engines with controlled auto-ignition combustion
Jun-mo Kang, Ann Arbor, MI (US);
Chen-fang Chang, Troy, MI (US);
Zongxuan Sun, Troy, MI (US);
Tang-wei Kuo, Troy, MI (US);
James A. Eng, Troy, MI (US);
Barry L. Brown, Lake Orion, MI (US);
Paul M. Najt, Bloomfield Hills, MI (US);
Man-feng Chang, Troy, MI (US);
Jun-Mo Kang, Ann Arbor, MI (US);
Chen-Fang Chang, Troy, MI (US);
Zongxuan Sun, Troy, MI (US);
Tang-Wei Kuo, Troy, MI (US);
James A. Eng, Troy, MI (US);
Barry L. Brown, Lake Orion, MI (US);
Paul M. Najt, Bloomfield Hills, MI (US);
Man-Feng Chang, Troy, MI (US);
GM Global Technology Operations, Inc., Detroit, MI (US);
Abstract
A direct injection controlled auto-ignition engine is operated at steady state, within a homogeneous charge compression-ignition (HCCI) load range and with fuel-air-diluent mixtures at predetermined conditions, for each speed and load, of engine control inputs, including at least fueling mass flow rate, injection timing (FI), spark timing (SI) and exhaust recompression obtained by negative valve overlap (NVO). During load change rates below a predetermined threshold, SI, FI and NVO change rates are synchronized to current changes in the fueling mass flow rate. For fast load increases above the threshold, the cylinder charge is temporarily enriched by increasing the percentage of residual gas or reducing the percentage of fresh air mass in the charge sufficiently to maintain auto-ignition temperature during the load change. This may be done by delaying NVO action for a predetermined speed-dependent number of engine cycles. At very low loads, stable fuel rate reduction may require an alternate method involving deceleration fuel cut-off followed by a step change during refire.