Methods and systems for a throttle turbine generator

Patent metadata

Field	Value
Publication number	US-9581095-B2
Application number	US-201414484081-A
Country	US
Kind code	B2
Filing date	Sep 11, 2014
Priority date	Sep 11, 2014
Publication date	Feb 28, 2017
Grant date	Feb 28, 2017

Abstract

Methods and systems are provided for adjusting operation of a throttle turbine generator to enable improved canister purging. A pressure differential across an intake throttle may be harnessed to rotate a turbine coupled in a throttle bypass, the turbine in turn driving a generator to charge a battery. During low intake manifold vacuum conditions, the generator may be operated as a motor to rotate the turbine, and use a compressor effect of the turbine to purge fuel vapors from a fuel system canister.

First claim

The invention claimed is:

1. A method for an engine, comprising:
selectively operating a motor-generator to rotate a turbine coupled in an intake throttle bypass; and
drawing fuel vapors from a fuel system canister into an engine intake manifold via the rotation of the turbine.

2. The method of claim 1 , wherein the selectively operating includes operating the motor-generator during conditions when the engine is operating without boost and while the intake manifold vacuum is lower than a threshold.

3. The method of claim 2 , further comprising, during conditions when the engine is operating without boost and the intake manifold vacuum is higher than the threshold, drawing fuel vapors from the fuel system canister into the engine intake manifold via intake manifold vacuum.

4. The method of claim 3 , further comprising, during conditions when the engine is operating without boost and the intake manifold vacuum is higher than the threshold, directing intake air through the intake throttle bypass and through the turbine to rotate the turbine, the rotating turbine driving the motor-generator.

5. The method of claim 4 , further comprising, while the rotating turbine drives the motor-generator, charging a battery electrically coupled to the motor-generator.

6. The method of claim 5 , wherein selectively operating the motor-generator to rotate the turbine includes drawing charge from the battery.

7. The method of claim 4 , wherein when operating the motor-generator to rotate the turbine, the motor-generator is operating as a motor, and when the rotating turbine drives the motor-generator, the motor-generator is operating as a generator.

8. The method of claim 4 , wherein when operating the motor-generator to rotate the turbine, the turbine is operating as a compressor, and when the rotating turbine drives the motor-generator, the turbine is operating as a turbine.

9. The method of claim 2 , wherein the threshold is based on a load of the fuel system canister.

10. A method, comprising:
operating an engine in a first mode, when intake vacuum is above a threshold, with a turbine coupled in a throttle bypass driving a motor-generator; and
operating the engine in a second mode, when intake vacuum is below the threshold, with the turbine coupled in the throttle bypass being driven by the motor-generator.

11. The method of claim 10 , wherein during the first mode, air is drawn through the turbine into an intake manifold to drive the motor-generator, and wherein during the second mode, air is drawn through a fuel vapor canister and via the turbine into the intake manifold.

12. The method of claim 11 , wherein during the first mode, the fuel vapor canister is purged using intake manifold vacuum, and wherein during the second mode, the fuel vapor canister is purged using the air drawn into the intake manifold via rotation of the turbine.

13. The method of claim 12 , wherein during the first mode, the motor-generator operates as a generator and electrical energy is stored in a battery coupled to the motor-generator; and wherein during the second mode, the motor-generator operates as a motor and electrical energy is drawn from the battery coupled to the motor-generator.

14. The method of claim 10 , wherein during the second mode, the turbine is switched from a turbine mode of operation to a compressor mode of operation.

15. The method of claim 11 , wherein during the first mode, a bypass valve coupled in the throttle bypass upstream of the turbine is opened, and wherein during the second mode, a purge valve coupled between the canister and the throttle bypass is opened.

16. The method of claim 11 , wherein during the first mode, an intake throttle opening is increased based on throttle bypass flow through the turbine, and wherein during the second mode, the intake throttle opening is decreased based on purge flow from the canister.

17. A system, comprising:
a throttle disposed in an intake passage of an engine;
a throttle bypass configured to route intake air from a position upstream of the throttle to a position downstream of the throttle, the throttle bypass including a throttle bypass valve;
a turbine disposed in the throttle bypass, the turbine mechanically coupled to a motor-generator the motor-generator in electrical communication with a battery;
a fuel system including a canister configured to receive fuel vapors from a fuel tank, the canister coupled to the throttle bypass downstream of the bypass valve and upstream of the turbine via a purge valve; and
a controller configured with computer readable instructions stored on non-transitory memory for:
when intake manifold vacuum is lower,
operating the motor-generator while drawing energy from the battery to rotate the turbine as a compressor; and
drawing intake air through the canister into an intake manifold via the rotation of the turbine as a compressor to purge the canister.

18. The system of claim 17 , wherein the controller includes further instructions for:
when the intake manifold vacuum is higher,
drawing intake air through the throttle bypass to rotate the turbine and drive the motor-generator while storing energy in the battery; and
purging the canister by drawing intake air through the canister into the intake manifold using the intake manifold vacuum.

19. The system of claim 18 , wherein when the intake manifold vacuum is higher, the turbine operates as a generator-driving turbine, and wherein when the intake manifold vacuum is lower, the turbine operates as a motor-driven compressor.

20. The system of claim 19 , wherein the controller includes further instructions for increasing an opening of the throttle during the drawing of intake air through the throttle bypass to rotate the turbine and drive the motor-generator; and decreasing an opening of the throttle during the drawing of intake air through the canister to purge the canister.

Assignees

• Ford Global Tech Llc

Inventors

• Pursifull Ross Dykstra

Classifications

• F02M25/089

  Layout of the fuel vapour installation · CPC title

• F02M35/10222

  Exhaust gas recirculation [EGR]; Positive crankcase ventilation [PCV]; Additional air admission, lubricant or fuel vapour admission · CPC title

• F02D41/0032 Primary

  Controlling the purging of the canister as a function of the engine operating conditions · CPC title

• F01D15/10

  Adaptations for driving, or combinations with, electric generators · CPC title

• F02D41/18

  by measuring intake air flow · CPC title