Patent ID: 6378308
Filing Date: 2002-04-30
Classification: F01N,F02B,F02M,Y02T

Abstract:
A turbocharged internal combustion engine (10);(1.1) with at least one high-pressure stage (20); (1.2) with at least one low-pressure stage (30), which is arranged down stream of the high-pressure stage (20) (1.3) pipe, (60, 61) for connection of the inlet side of the high-pressure turbine (21) and the exhaust side (12) of the engine (10) and for connection of the low-pressure turbine (31) to the outlet side of the high-pressure turbine (21); (1.4) with at least one bypass pipe (24, 24a, 24b), which has at least one pipe switch (70, 71), and which connects the exhaust side (12) of the engine (10) to the inlet side of the low-pressure turbine (31); (1.5) with sensors for detecting the operating parameters of the engine (10); (1.6) the high-pressure turbine (21) is always flowed through by a minimum exhaust mass flow so that it continuously circulates; characterized by the following features: (1.7) a central processing unit (CPU) is provided, which is fed with signals of the sensors; (1.8) the CPU actuates the at least one pipe switch (70, 71, 50) in such a way that variable partial flows of the entire exhaust mass flow are distributed to the high-pressure turbine (21), to the low-pressure turbine (31) and optionally to the fresh air side of the engine (10), and namely for the purpose of optimizing both the stationary and the non-steady mode of operation of the engine (10) with a view to minimizing fuel consumption and/or pollutant emission; (1.9) the at least one pipe switch is actuated in such a way, that with low load of the engine (10) the expansion work is shifted to the low-pressure turbine (31) and with high load of the engine (10) the expansion work is shifted to the high-pressure turbine (21); and (1.10) the one or more bypass channels (24, 24a,b) and the one or more outlet-side pipes terminate in a common pipe (62), which is connected to the low-pressure turbine (31).