System and method for balancing outputs from multiple cylinder banks of an internal combustion engine
The present disclosure relates to engines with multiple cylinder banks. Systems and methods are disclosed that relate to engine operations that balance the output from the cylinder banks to improve engine health and performance.
1 . A method, comprising:
operating an internal combustion engine system including an engine with first and second cylinder banks, each of the first and second cylinder banks including a plurality of cylinders for receiving fuel from a fuel system to combust with air from an intake system;
comparing a first output from combustion in the first cylinder bank with a second output from combustion in the second cylinder bank; and
in response to the comparison, incrementally adjusting an operating parameter on a cylinder-by-cylinder basis for all or a subset of the plurality of cylinders in at least one of the first and second cylinder banks to reduce a difference between the first output and the second output.
2 . The method of claim 1 , wherein comparing the first output and the second output includes determining a difference between the first output and the second output is greater than a first threshold amount.
3 . The method of claim 2 , wherein incrementally adjusting the operating parameter includes incrementally adjusting the operating parameter until the difference is less than a second threshold amount.
4 . The method of claim 3 , wherein the second threshold amount is less than the first threshold amount.
5 . The method of claim 1 , further comprising incrementally adjusting the operating parameter on a cylinder-by-cylinder basis for only subsets of the plurality of cylinders in each of the first and second cylinder banks in opposite directions from one another until the difference between the first output and the second output is reduced to less than a threshold amount.
6 . The method of claim 1 , wherein the first output and the second output are NOx values.
7 . The method of claim 1 , wherein the first output and the second output are one of: exhaust oxygen values, particulate mass and/or particulate number values, carbon dioxide values, knock values, exhaust temperature values, exhaust pressure values, turbine speed values, breakdown voltage values, and ignition temperature values.
8 . The method of claim 1 , wherein the operating parameter is a sparking timing that is adjusted on the cylinder-by-cylinder basis in at least one of the first and second cylinder banks until the difference between the first output and the second output is reduced to less than a threshold amount.
9 . The method of claim 1 , wherein the operating parameter is a sparking timing that is adjusted on the cylinder-by-cylinder basis of each of the first and second cylinder banks until the difference between the first output and the second output is reduced to less than a threshold amount.
10 . The method of claim 9 , wherein incrementally adjusting the operating parameter includes advancing the spark timing on the cylinder-by-cylinder basis in the first cylinder bank and retarding the spark timing on the cylinder-by-cylinder basis of the second cylinder bank.
11 . The method of claim 1 , wherein the operating parameter is an air-fuel ratio that is adjusted on the cylinder-by-cylinder basis in at least one of the first and second cylinder banks.
12 . The method of claim 1 , wherein the operating parameter is an air-fuel ratio that is adjusted on the cylinder-by-cylinder basis in each of the first and second cylinder banks.
13 . The method of claim 11 , wherein incrementally adjusting the operating parameter includes increasing the air-fuel ratio on the cylinder-by-cylinder basis in the first cylinder bank and decreasing the air-fuel ratio on the cylinder-by-cylinder basis in the second cylinder bank.
14 . An internal combustion engine system, comprising:
an internal combustion engine with a a first cylinder bank and a second cylinder bank, each of the first cylinder bank and the second cylinder bank including a plurality of cylinders of the internal combustion engine;
a fuel system configured to fuel the first and second cylinder banks;
an intake system configured to provide air flow to the plurality of cylinders;
an exhaust system to receive an exhaust flow from the first and second cylinder banks;
a first sensor operable to provide a first signal indicative of a first output from the first cylinder bank and a second sensor operable to provide a second signal indicative of a second output from the second cylinder bank; and
a controller configured to receive the first and second signals from the first and second sensors, the controller further being configured to compare the first output from the first cylinder bank with the second output from the second cylinder bank and, in response to the comparison, incrementally adjust an operating parameter on a cylinder-by-cylinder basis for all or a subset of the plurality of cylinders in at least one of the first and second cylinder banks to reduce a difference between the first output and the second output.
15 . The system of claim 14 , wherein the intake system includes:
a first intake manifold configured to distribute the air flow to the first cylinder bank; and
a second intake manifold configured to distribute the air flow to the second cylinder bank.
16 . The system of claim 14 , wherein the exhaust system includes:
a first exhaust manifold configured to receive exhaust flow from the first cylinder bank; and
a second exhaust manifold configured to receive exhaust flow from the second cylinder bank.
17 . The system of claim 14 , wherein the controller is configured to:
determine a difference between the first output and the second output is greater than a first threshold amount; and
incrementally adjust the operating parameter until the difference is less than a second threshold amount.
18 . The system of claim 14 , wherein the controller is configured to incrementally adjust the operating parameter for only subsets of the plurality of cylinders in each of the first and second cylinder banks in an opposite direction from one another until the difference between the first output and the second output is reduced to less than a threshold amount.
19 . The system of claim 14 , wherein the first output and the second output are NOx values.
20 . The system of claim 14 wherein the first output and the second output are one of: exhaust oxygen values, particulate mass and/or particulate number values, carbon dioxide values, knock values, exhaust temperature values, exhaust pressure values, turbine speed values, breakdown voltage values, and ignition temperature values.
21 . The system of claim 14 , wherein the operating parameter is a sparking timing that is adjusted on the cylinder-by-cylinder basis of at least one of the first and second cylinder banks until the difference between the first output and the second output is reduced to less than a threshold amount.
22 . The system of claim 14 , wherein the operating parameter is an air-fuel ratio that is adjusted on the cylinder-by-cylinder basis of at least one of the first and second cylinder banks until the difference between the first output and the second output is reduced to less than a threshold amount.