| 摘要 |
<p>A charge limit manager arbitrates between desired EGR system and/or turbocharger behavior and the actual capabilities of EGR system and/or turbocharger control mechanisms under current operating conditions. In one embodiment, the charge limit manager includes three limiter blocks producing offset signals as separate functions of turbocharger compressor outlet temperature, turbocharger speed and pressure differential (ΔP) across an EGR valve. A charge limit selector block is responsive to the offset values produced thereby, and also to commanded values of charger flow of EGR fraction as well as operation values of EGR valve position and ΔP, to limit the charge flow and EGR fraction commands to controllable values. These values are preferably substracted from actual or estimated values of charge flow and EGR fraction to produce charge flow and EGR fraction error values for use in controlling one or more EGR system and/or turbocharger swallowing capacity/efficiency control mechanisms.</p> |
