Energy balance based boost control using feedback linearization

Patent metadata

Field	Value
Publication number	US-2016160771-A1
Application number	US-201414562820-A
Country	US
Kind code	A1
Filing date	Dec 8, 2014
Priority date	Dec 8, 2014
Publication date	Jun 9, 2016
Grant date	—

Abstract

An internal combustion engine includes an air charging system with a boost air system. A method to control the boost air in the air charging system, decoupled from the air and EGR system controls, includes monitoring a reference boost pressure and operating parameters of the air charging system; creating a turbocharger energy balance model of the air charging system; applying feedback linearization control to the turbocharger energy balance model to create an approximately linearized feedback system; and determining a boost control command for the air charging system using the approximately linearized feedback system based on the monitored reference boost pressure and the monitored operating parameters of the air charging system. The boost air in the air charging system is controlled based upon the boost control command.

First claim

1 . Method to control boost air in an air charging system in an internal combustion engine, the method comprising:
monitoring a reference boost pressure; monitoring operating parameters of the air charging system; creating a turbocharger energy balance model of the air charging system; applying feedback linearization control to the turbocharger energy balance model to create an approximately linearized feedback system; determining a boost control command for the air charging system using the approximately linearized feedback system based on the monitored reference boost pressure and the monitored operating parameters of the air charging system; controlling the boost air in the air charging system based upon the boost control command.

2 . The method of claim 1 , wherein the reference boost pressure comprises a desired boost pressure.

3 . The method of claim 1 , wherein the operating parameters of an air charging system comprises an actual boost pressure.

4 . The method of claim 1 , wherein the operating parameters of the air charging system comprise fresh mass air flow, fuel flow, intake manifold pressure, intake manifold temperature, ambient pressure and ambient temperature, and engine exhaust temperature.

5 . The method of claim 1 , wherein said turbocharger energy balance model of the air charging system is expressed by the following relationship:
{dot over (p)} rc =−c*h c r c ( p rc ,Q c )+ c*h t r t wherein p rc is a compressor pressure ratio,
c is a constant determined based on the relationship between the compressor pressure ratio and the square of the turbo speed,
h c is a fresh air energy flow into a compressor,
r c is a compressor power increase rate,
Q c is a corrected compressor flow,
h t is an exhaust energy flow into a turbine, and
r t is a turbine power transfer rate.

6 . The method of claim 1 , wherein said turbocharger energy balance model of the air charging system is expressed by the following relationship:
{dot over (p)} rc =−c*h c r c ( p rc ,Q c )+ c*h t r t +J ( {dot over (Q)} c ,Q c ) wherein p rc is a compressor pressure ratio,
c is a constant determined based on the relationship between the compressor pressure ratio and the square of the turbo speed,
h c is a fresh air energy flow into a compressor,
r c is a compressor power increase rate,
Q c is a corrected compressor flow,
h t is an exhaust energy flow into a turbine,
r t is a turbine power transfer rate, and
J({dot over (Q)} c , Q c ) is a turbo inertia effect.

7 . The method of claim 1 , wherein applying feedback linearization control to the turbocharger energy balance model to create an approximately linearized feedback system is expressed by the following relationship:

r
t

=

1

h
t



(

h
c



r
c



(

p

r



c

,

Q
c

)

-

1
c



J


(

Q
.

c

,

Q
c

)

+

1
c


v

)

wherein p rc is a compressor pressure ratio,
c is a constant determined based on the relationship between the compressor pressure ratio and the square of the turbo speed,
h c is a fresh air energy flow into a compressor,
r c is a compressor power increase rate,
Q c is a corrected compressor flow,
h t is an exhaust energy flow into a turbine,
r t is a turbine power transfer rate,
v is a feedback control signal based on a feedback control method, and
J({dot over (Q)} c , Q c ) is a turbo inertia effect.

8 . The method of claim 1 , wherein determining a boost control command for the air charging system using the approximately linearized feedback system based on the monitored reference boost pressure and the monitored operating parameters of the air charging system comprises:
determining a desired compressor power, an exhaust energy flow into a turbine, and a turbo inertia based on the monitored operating parameters of the air charging system; determining a boot pressure error between the reference boost pressure and an actual boost pressure; applying feedback control methods to the boost pressure error to determine a feedback control signal; determining a turbine power transfer rate based on the desired compressor power, the energy flow into a turbine, the turbo inertia and the feedback control signal; and converting the turbine power transfer rate into the boost control command for the air charging system.

9 . The method of claim 1 , wherein determining a boost control command for the air charging system using the approximately linearized feedback system based on the monitored reference boost pressure and the monitored operating parameters of the air charging system comprises:
determining a desired compressor power, an exhaust energy flow into a turbine, and a turbo inertia based on the monitored operating parameters of the air charging system; determining a feedforward control signal based on the desired compressor power, the exhaust energy flow into the turbine, and the turbo inertia; determining a boot pressure error between the reference boost pressure and an actual boost pressure; applying feedback control methods to the boost pressure error to determine a feedback control signal; determining a boost control command fo

Assignees

• Gm Global Tech Operations Inc

Inventors

• Wang Yue-Yun
• Haskara Ibrahim
• Alfieri Vincenzo
• Conte Giuseppe

Classifications

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02B33/40

  of non-positive-displacement type · CPC title

• F02D41/18

  by measuring intake air flow · CPC title

• F02B37/12

  Control of the pumps · CPC title

• F02D41/0007 Primary

  for control of turbo-charged or super-charged engines (control of the pumps per se F02B37/12) · CPC title