Methods and system for improving compressor recirculation valve operation

Patent metadata

Field	Value
Publication number	US-2016169089-A1
Application number	US-201414566488-A
Country	US
Kind code	A1
Filing date	Dec 10, 2014
Priority date	Dec 10, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

Systems and methods for improving compressor recirculation valve operation of an engine that includes a compressor are presented. The systems and methods adjust a position of a waste gate while the compressor recirculation valve is operated in a closed loop mode to maintain engine intake manifold throttle inlet pressure during a diagnostic mode to adapt operation of the compressor recirculation valve.

First claim

1 . A diagnostic method, comprising:
at least partially opening a waste gate and adjusting a compressor recirculation valve to a closed position in response to a diagnostic request; at least partially closing the waste gate after at least partially opening the waste gate; adjusting a compressor recirculation valve airflow offset in response to a position the compressor recirculation valve is adjusted to maintain a central throttle inlet pressure responsive to the at least partially closing the waste gate; and operating the compressor recirculation valve in response to the airflow offset.

2 . The method of claim 1 , where the diagnostic request is a request to adjust the compressor recirculation valve airflow offset.

3 . The method of claim 1 , further comprising adjusting a position of a central throttle to maintain a substantially constant engine airflow.

4 . The method of claim 1 , where the compressor recirculation valve is operated in a closed loop mode where compressor recirculation valve position is adjusted in response to the central throttle inlet pressure.

5 . The method of claim 4 , where the compressor recirculation valve is at least partially opened in response to the at least partially closing the waste gate.

6 . The method of claim 1 , where the waste gate is at least partially closed in a step-wise manner in a compressor recirculation valve adaptation mode, and further comprising exiting the compressor recirculation valve adaptation mode in response to an increase in driver demand torque.

7 . The method of claim 1 , where the recirculation valve airflow offset is an opening position of the compressor recirculation valve where airflow greater than a threshold amount is present.

8 . A diagnostic method, comprising:
partially opening a waste gate, adjusting a compressor recirculation valve to a closed position, and maintaining a constant engine throttle inlet pressure via adjusting a position of the compressor recirculation valve in response to a diagnostic request after the compressor recirculation valve has closed; at least partially closing the waste gate after the compressor recirculation valve is closed; adjusting a recirculation valve transfer function in response to a position of the compressor recirculation valve where the constant engine throttle inlet pressure is maintained after the waste gate is at least partially closed; and operating the compressor recirculation valve in response to the compressor recirculation valve transfer function.

9 . The method of claim 1 , where the compressor recirculation valve is closed loop controlled responsive to engine intake throttle inlet pressure.

10 . The method of claim 8 , where the diagnostic request is a compressor recirculation valve diagnostic request.

11 . The method of claim 8 , where the diagnostic request initiates a diagnostic mode, and further comprising adjusting an engine intake manifold throttle to provide a constant engine air flow during the diagnostic mode.

12 . The method of claim 11 , further comprising exiting the diagnostic mode in response to an increase in driver demand torque.

13 . The method of claim 8 , where the compressor recirculation valve is positioned in parallel with a compressor.

14 . A system, comprising:
an engine; a turbocharger including a compressor mechanically coupled to the engine, the turbocharger including a waste gate; a recirculation valve positioned in an air intake of the engine in parallel with the compressor; and a controller including instructions stored in non-transitory memory for at least partially closing an at least partially open waste gate and adjust a transfer function of the recirculation valve based on the at least partially closing the at least partially open waste gate in response to a request to adapt operation of the recirculation valve.

15 . The system of claim 14 , further comprising additional instructions to closed loop control the recirculation valve to maintain a constant engine intake manifold throttle inlet pressure.

16 . The system of claim 14 , where an offset value of the transfer function is adjusted.

17 . The system of claim 14 , further comprising additional instructions to maintain a constant engine air flow via adjusting a positon of an engine intake manifold throttle.

18 . The system of claim 14 , where the recirculation valve is initially closed in response to the request to adapt operation of the recirculation valve.

19 . The system of claim 18 , further comprising additional instructions for exiting a recirculation valve diagnostic mode in response to an increase in driver demand torque.

20 . The system of claim 14 , further comprising additional instructions to operate the recirculation valve in response to the transfer function.

Assignees

• Ford Global Tech Llc

Inventors

• Xiao Baitao
• Banker Adam Nathan
• Ossareh Hamid-Reza

Classifications

• F02D2200/0406

  Intake manifold pressure · CPC title

• F02D41/221

  relating to the failure of actuators or electrically driven elements · CPC title

• F02B37/18

  by bypassing exhaust {from the inlet to the outlet of turbine or to the atmosphere} · CPC title

• Y02T10/40

  Engine management systems · CPC title

• F02D41/0007 Primary

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