Methods and system for determining compressor recirculation valve sludge

Patent metadata

Field	Value
Publication number	US-2016169092-A1
Application number	US-201414566442-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 determining the presence or absence of deposits that may accumulate within a compressor recirculation valve positioned in parallel with a turbocharger compressor are presented. The systems and methods adjust actuators to maintain engine operation such that it may be more difficult for a driver to become aware that a compressor recirculation valve diagnostic is being executed.

First claim

1 . A diagnostic method, comprising:
partially opening a waste gate and adjusting a compressor recirculation valve to a closed position in response to a diagnostic request; incrementally opening the compressor recirculation valve after the compressor recirculation valve is closed; adjusting a compressor recirculation valve airflow offset in response to waste gate position while incrementally opening the compressor recirculation valve from the closed position; 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 the waste gate position in response to an throttle inlet pressure.

4 . The method of claim 3 , where the waste gate position is adjusted to maintain a pressure at a throttle inlet.

5 . The method of claim 4 , where the waste gate position is closed while incrementally opening the compressor recirculation valve.

6 . The method of claim 1 , where the compressor recirculation valve is incrementally opened during 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 compressor 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 waste gate in response to a diagnostic request; incrementally opening the compressor recirculation valve 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 waste gate position is first adjusted after the compressor recirculation valve is closed and the constant engine throttle inlet pressure is maintained; and operating the compressor recirculation valve in response to the compressor recirculation valve transfer function.

9 . The method of claim 1 , where waste gate is closed in response to a reduction in engine 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 holding an engine intake manifold throttle at a constant position 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 adjusting a position of the waste gate to maintain engine intake manifold throttle inlet pressure at a constant pressure and adjust a transfer function of the recirculation valve in response to a position of the recirculation valve that causes the position of the waste gate to be adjusted to maintain engine intake manifold throttle inlet pressure.

15 . The system of claim 14 , further comprising additional instructions to closed loop control the waste gate to maintain 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 incrementally open the recirculation valve.

18 . The system of claim 14 , where the position of the recirculation valve is a position where air begins to recirculate from an output of a compressor to an inlet of the compressor.

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

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

Classifications

• F02B2039/162

  Control of pump parameters to improve safety thereof · CPC title

• Y02T10/40

  Engine management systems · CPC title

• F02B37/18

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

• F02D41/221

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

• F02D41/0007 Primary

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