Feed forward exhaust throttle and wastegate control for an engine

Patent metadata

Field	Value
Publication number	US-2017051684-A1
Application number	US-201514832227-A
Country	US
Kind code	A1
Filing date	Aug 21, 2015
Priority date	Aug 21, 2015
Publication date	Feb 23, 2017
Grant date	—

Abstract

Controlling an exhaust gas temperature of an engine. An electronic control unit receives a parameter setpoint command, monitors parameters of an engine using a plurality of sensors, receives measured engine states based on the monitored engine parameters from the plurality of sensors, generates measured engine state estimates and controlled engine state estimates using an engine observer model, determines an observer error based on a difference between the measured engine states and the measured engine state estimates, generates model corrections based on the observer error, generates a desired exhaust throttle valve position using an inverse engine model based on the parameter setpoint command, the controlled engine state estimates, and the model corrections, and adjusts a position of the exhaust throttle valve based on the desired exhaust throttle position.

First claim

What is claimed is:

1 . A method of controlling exhaust gas temperature for an engine, the engine including an air system having an exhaust throttle valve, the method comprising:
receiving a parameter setpoint command at an inverse engine model; monitoring parameters of the engine using a plurality of sensors; receiving measured engine states based on the monitored engine parameters from the plurality of sensors; generating measured engine state estimates and controlled engine state estimates using an engine observer model, the controlled engine state estimates being received by the inverse engine model; determining an observer error based on a difference between the measured engine states and the measured engine state estimates; generating model corrections based on the observer error, the model corrections being received by the inverse engine model; generating a desired exhaust throttle valve position using the inverse engine model based on the parameter setpoint command, the controlled engine state estimates, and the model corrections; and adjusting a position of the exhaust throttle valve based on the desired exhaust throttle position.

2 . The method of claim 1 , further comprising determining a desired turbine outlet pressure.

3 . The method of claim 2 , wherein the desired turbine outlet pressure is determined based on a desired turbine power, an exhaust manifold pressure, an after treatment system inlet pressure, and a turbine mass flow setpoint.

4 . The method of claim 3 , wherein the desired turbine power is determined based on a desired compressor power.

5 . The method of claim 4 , wherein the desired compressor power is determined based on a desired intake manifold pressure and a desired compressor mass flow.

6 . The method of claim 1 , wherein the parameter setpoint command is selected from the group consisting of: a desired diluent-to-air (“D/A”) ratio, a desired fuel-to-air (“F/A”) ratio, and a desired exhaust manifold delta pressure.

7 . The method of claim 1 , further comprising generating a desired wastegate valve position using the inverse engine model based on the parameter setpoint command, the controlled engine state estimates, and the model corrections; and
adjusting a position of the wastegate valve based on the desired wastegate valve position.

8 . The method of claim 7 , wherein the desired wastegate valve position is determined based on a wastegate valve maximum position and a low pressure turbine mass flow setpoint.

9 . The method of claim 8 , wherein the low pressure turbine mass flow setpoint is determined based on an exhaust manifold pressure and a desired exhaust manifold pressure.

10 . The method of claim 9 , wherein the desired exhaust manifold pressure is determined based on a minimum exhaust manifold pressure and a desired exhaust manifold delta pressure.

11 . A system for controlling exhaust gas temperature, the system comprising:
an engine including an air system and an exhaust throttle valve; a plurality of sensors for monitoring parameters of the engine; and an electronic control unit including a processor and a memory, the electronic control unit operable to
receive a parameter setpoint command at an inverse engine model,
monitor parameters of the engine using the plurality of sensors,
receive measured engine states based on the monitored engine parameters from the plurality of sensors,
generate measured engine state estimates and controlled engine state estimates using an engine observer model, the controlled engine state estimates being received by the inverse engine model,
determine an observer error based on a difference between the measured engine states and the measured engine state estimates,
generate model corrections based on the observer error, the model corrections being received by the inverse engine model,
generate a desired exhaust throttle valve position using the inverse engine model based on the parameter setpoint command, the controlled engine state estimates, and the model corrections, and
adjust a position of the exhaust throttle valve based on the desired exhaust throttle position.

12 . The system of claim 11 , wherein the electronic control unit is further operable to determine a desired turbine outlet pressure.

13 . The system of claim 12 , wherein the desired turbine outlet pressure is determined based on a desired turbine power, an exhaust manifold pressure, an after treatment system inlet pressure, and a turbine mass flow setpoint.

14 . The system of claim 13 , wherein the desired turbine power is determined based on a desired compressor power.

15 . The system of claim 14 , wherein the desired compressor power is determined based on a desired intake manifold pressure and a desired compressor mass flow.

16 . The system of claim 11 , wherein the parameter setpoint command is selected from the group consisting of: a desired diluent-to-air (“D/A”) ratio, a desired fuel-to-air (“F/A”) ratio, and a desired exhaust manifold delta pressure.

17 . The system of claim 11 , wherein the electronic control unit is further operable to generate a desired wastegate valve position using the inverse engine model based on the parameter setpoint command, the controlled engine state estimates, and the model corrections; and
adjust a position of the wastegate valve based on the desired wastegate valve position.

18 . The system of claim 17 , wherein the desired wastegate valve position is determined based on a wastegate valve maximum position and a low pressure turbine mass flow setpoint.

19 . The system of claim 18 , wherein the low pressure turbine mass flow setpoint is determined based on an exhaust manifold pressure and a desired exhaust manifold pressure.

20 . The system of claim 19 , wherein the desired exhaust manifold pressure is determined based on a minimum exhaust manifold pressure and a desired exhaust manifold delta pressure.

Assignees

• Deere & Co

Inventors

• Lahti John L
• Ridenour Dustin W
• Maney Michael J
• Pipho Michael J

Classifications

• F02B29/0406

  Layout of the intake air cooling or coolant circuit · CPC title

• F02B37/22

  by varying cross-section of exhaust passages or air passages {, e.g. by throttling turbine inlets or outlets or by varying effective number of guide conduits} (F02B37/24 takes precedence) · CPC title

• F02B37/004

  with exhaust drives arranged in series · CPC title

• F02D2041/1416

  Observer · CPC title

• F02D41/0002

  Controlling intake air · CPC title