Patent ID: 7941999
Filing Date: 2011-05-17
Classification: F02B,F02M

Abstract:
1. A method of controlling an internal combustion engine ( 1 ) comprising first and second groups ( 6 , 7 ) of cylinders (A 1 -A 8 , B 1 -B 8 ), at least one exhaust gas turbocharger ( 2 A, 2 B) with a compressor ( 3 A, 3 B) and with a turbine ( 4 A, 4 B), a charge air supply line ( 5 A, 5 B) for supplying compressed air to the cylinders (A 1 -A 8 , B 1 -B 8 ) of the internal combustion engine ( 1 ), the second cylinder group ( 7 ) operating in accordance with a spender principle providing exhaust gas for exhaust gas recirculation purposes, an exhaust gas collection line ( 8 A, 8 B) connected to the cylinders (A 1 -A 8 , B 1 -B 8 ) and having a first section ( 9 ) for the collection of exhaust gas from the first cylinder group ( 6 ) and a second section ( 10 ) for the collection of exhaust gases from the second cylinder group ( 7 ), a first exhaust gas line ( 13 ) by which the first section ( 9 , 8 A) of the exhaust gas collection line ( 8 A, 8 B) is connected to the turbine ( 4 A, 4 B), an exhaust gas recirculation line ( 11 ) for recirculating exhaust gas from the second section ( 10 ) of the gas collection line ( 8 A) to the charge air supply line ( 5 A, 5 B) and a first control device ( 12 ) for controlling the exhaust gas flow from the first section ( 9 ) to the second section ( 10 ) of the exhaust gas collection line ( 8 A), said first exhaust gas line ( 13 ) including a second control device ( 14 ) for controlling the exhaust gas flow to the turbine ( 4 A, 4 B) and a third control device ( 15 ) arranged in the recirculation line ( 11 ) for controlling the exhaust gas recirculation flow to the charge air supply lines ( 5 A, 5 B), said method comprising the steps of: establishing during engine warm-up in first mode of operation an exhaust gas recirculation rate of zero (AGRR=0), establishing during normal engine operation in a predetermined power output and speed range in a second mode of operation an exhaust gas recirculation rate (AGRR) in a range of larger than zero and smaller than a certain limit value (GW) (0≦AGRR≦GW), wherein the limit value (GW) is determined by the ratio of the cylinder number included in the second cylinder group ( establishing during HCCI (Homogenous Charge Compression Ignition) operation in a third mode of operation, an exhaust gas recirculation rate (AGRR) which is greater than the limit value (AGRR>GW).