System and method for operating a turbocharged engine
View Patent ↗A method includes substantially eliminating surge of a compressor and reducing specific fuel consumption and exhaust emissions of an engine by adjusting exhaust flow through an exhaust gas recirculation system, by adjusting airflow through a compressor recirculation valve, by adjusting fuel injection timing, or by adjusting a combination thereof in response to variance in a plurality of parameters. The parameters include quantity of exhaust emissions, a maximum in-cylinder pressure of the engine, an area ratio of an exhaust gas recirculation mixer of the exhaust gas recirculation system, estimated or sensed compressor surge, engine load, altitude of operation, or combinations of the parameters thereof.
1. A method of operating a turbocharged engine system via a controller, comprising:
determining via the controller a quantity of NOx emissions of an engine;
determining via the controller an altitude of operation of the turbocharged engine system; and
if the altitude of operation of the turbocharged engine system is less than or equal to a predetermined altitude limit, adjusting via the controller exhaust flow through an exhaust gas recirculation system in response to the quantity of NOx emissions, wherein adjusting exhaust flow through the exhaust gas recirculation system comprises controlling an exhaust gas recirculation valve and/or an exhaust gas recirculation pump.
2. The method of claim 1 , further comprising comparing an ambient temperature of the turbocharged engine system to a predetermined ambient temperature limit.
3. The method of claim 2 , further comprising advancing a fuel injection timing when the NOx emissions of the engine are less than or equal to the predetermined NOx emission limit.
4. The method of claim 1 , further comprising advancing a fuel injection timing when the altitude of operation of the turbocharged engine system is greater than a predetermined altitude limit.
5. The method of claim 1 , further comprising increasing the exhaust flow through the exhaust gas recirculation system when the NOx emissions of the engine are greater than a predetermined NOx emission limit.
6. The method of claim 1 , further comprising determining whether a compressor of the turbocharged engine system is in a surge condition.
7. The method of claim 6 , further comprising comparing a maximum in-cylinder pressure to a predetermined pressure limit when the compressor is not in the surge condition.
8. The method of claim 7 , further comprising increasing a percentage of exhaust gas recirculation through the exhaust gas recirculation system and advancing fuel injection timing when the maximum in-cylinder pressure is less than or equal to the predetermined pressure limit.
9. The method of claim 7 , further comprising comparing an amount of particulate matter in the exhaust emissions to a predetermined particulate matter limit when the maximum in-cylinder pressure is greater than the predetermined pressure limit.
10. The method of claim 9 , further comprising retarding fuel injection timing when the amount of particulate matter in the exhaust emissions is less than or equal to the predetermined particulate matter limit.
11. The method of claim 9 , further comprising derating the engine when the amount of particulate matter in the exhaust emissions is greater than the predetermined particulate matter limit.
12. A system, comprising:
a controller coupled to an emission sensor, a pressure sensor, a surge sensor, a load sensor, an altitude sensor, a temperature sensor, and a speed sensor configured to measure a quantity of exhaust emissions of an engine, a maximum in-cylinder pressure, a compressor surge, an engine load, an altitude of operation, an ambient temperature, and an engine speed respectively;
wherein the controller is configured to:
determine the quantity of exhaust emissions, and the maximum in-cylinder pressure; and
eliminate compressor surge and reduce specific fuel consumption and exhaust emissions of the engine by adjusting exhaust flow through the exhaust gas recirculation system in response to the quantity of exhaust emissions and the maximum in-cylinder pressure of the engine.
13. The system of claim 12 , further comprising an exhaust gas recirculation valve, an exhaust gas recirculation cooler, and an exhaust gas recirculation pump, wherein the controller is configured to control the exhaust gas recirculation valve, the exhaust gas recirculation cooler, and the exhaust gas recirculation pump.
14. The system of claim 12 , wherein the controller is configured to compare a sensed altitude of operation of the system to a predetermined altitude limit, or compare a sensed ambient temperature of the system to a predetermined ambient temperature limit.
15. The system of claim 14 , wherein the controller is configured to compare the quantity of exhaust emissions of the engine to a predetermined exhaust emission limit when the sensed altitude of operation of the turbocharged engine system is less than or equal to the predetermined altitude limit, or the sensed ambient temperature of the system is less than or equal to the predetermined ambient temperature limit.
16. The system of claim 15 , wherein the controller is configured to control a fuel injector to advance a fuel injection timing when the exhaust emissions of the engine are less than or equal to the predetermined exhaust emission limit, or when the sensed altitude of operation of the system is greater than the predetermined altitude limit, or the ambient temperature of the system is greater than the predetermined ambient temperature limit.
17. The system of claim 15 , wherein the controller is configured to control the exhaust gas recirculation system to increase a quantity of exhaust flow through the exhaust gas recirculation system when the exhaust emissions of the engine is greater than the predetermined exhaust emission limit.
18. The system of claim 15 , wherein the controller is configured to determine whether a compressor is in a surge condition.
19. The system of claim 18 , wherein the controller is configured to compare the maximum in-cylinder pressure to a predetermined pressure limit when the compressor is not in the surge condition.
20. The system of claim 19 , wherein the controller is configured to control the exhaust gas recirculation system to increase the exhaust flow through the exhaust gas recirculation system and a fuel injector to advance a fuel injection timing when the maximum in-cylinder pressure is less than or equal to the predetermined pressure limit.
21. The system of claim 19 , wherein the controller is configured to compare a sensed amount of particulate matter in the exhaust emissions to a predetermined particulate matter limit when the maximum in-cylinder pressure is greater than the predetermined pressure limit.
22. The system of claim 21 , wherein the controller is configured to control the fuel injector to retard a fuel injection timing when the sensed amount of particulate matter in the exhaust emissions is less than or equal to the predetermined particulate matter limit.
23. The system of claim 21 , wherein the controller is configured to derate the engine when the sensed amount of particulate matter in the exhaust emissions is greater than the predetermined particulate matter limit.
24. The system of claim 12 , further comprising a turbocharger coupled to the controller.
25. The system of claim 12 , wherein the controller is coupled to the engine, wherein the engine is a compression ignition engine.