摘要 |
<p>A system for decoupling EGR flow and turbocharger swallowing capacity/efficiency control mechanisms includes a multiple-input multiple-output (MIMO) transform manager coupled to one or more of an EGR valve, an exhaust throttle and a variable geometry turbocharger (VGT) actuator of an internal combustion engine. The MIMO transform manager is responsive to commanded charge flow and EGR fraction parameters to decouple the EGR/exhaust throttle and VGT control parameters such that these control mechanisms may be controlled individually and independently of each other. One transform output is provided to a first compensator for controlling EGR flow and/or exhaust throttle operation as a function of charge flow error. The other transform output is provided to a second independent compensator for controlling VGT operation also as a function of charge flow error. Both compensators are configured to provide for transient compensator gain adjustment based on the degree of charge flow error, and the VGT compensator is further configured to provide for transient compensator gain adjustment based on a ratio of commanded fueling and oxygen/fuel ratio. The resulting control strategy provides for independent control of EGR flow/exhaust throttle and a VGT actuator, thereby resulting in better and more consistent control over mass charge flow.</p> |