| 摘要 |
While an engine (10, 10A, 10B, 10C, 10D, 10E) is operating, a control system (22) processes data for certain engine operating parameters to calculate a quantity of exhaust gas needed to satisfy an exhaust gas recirculation requirement. If a primary EGR control loop (34) alone can satisfy the calculated quantity of exhaust gas, a secondary EGR control loop (36) is closed while the primary EGR control loop is controlled to satisfy the calculated quantity. When the processing determines that the primary EGR control loop alone cannot satisfy the calculated quantity, the secondary EGR control loop is open concurrently with the primary EGR control loop and both the primary EGR loop and the secondary EGR loop are controlled to cause the combined flow of exhaust gas through the primary EGR control loop and flow of exhaust gas through the secondary EGR control loop to satisfy the calculated quantity. |
