HYBRID CATALYST CONVECTIVE PREHEATING SYSTEM

• US 20110283675A1
• Filed: 05/19/2010
• Published: 11/24/2011
• Est. Priority Date: 05/19/2010
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Spohn, Brian L., Roos, Bryan Nathaniel, Gonze, Eugene V., Santoso, Halim G.
• Granted Patent: US 8,756,924 B2
• Time in Patent Office: Days
• US Class Current: 60/274
• CPC Class Codes: F01N 13/009 having two or more separate purifying devices arranged in series
• CPC Class Codes: F01N 2900/0602 Electrical exhaust heater signals
• CPC Class Codes: F01N 2900/08 said parameters being related to the engine
• CPC Class Codes: F01N 2900/1411 Exhaust gas flow rate, e.g. mass flow rate or volumetric flow rate
• CPC Class Codes: F01N 2900/1602 Temperature of exhaust gas apparatus
• CPC Class Codes: F01N 3/021 by means of filters
• CPC Class Codes: F01N 3/2006 Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating by electrically controlling the supply of combustible mixture or its constituents only F02D41/0235
• CPC Class Codes: F01N 3/2026 directly electrifying the catalyst substrate, i.e. heating the electrically conductive catalyst substrate by joule effect
• CPC Class Codes: F01N 3/22 Control of additional air supply only, e.g. using by-passes or variable air pump drives
• CPC Class Codes: F01N 3/30 Arrangements for supply of additional air control, e.g. using by-passes or variable air pump drives, F01N3/22
• CPC Class Codes: F01N 3/323 Electrically driven air pumps
• CPC Class Codes: F01N 9/00 Electrical control of exhaust gas treating apparatus monitoring or diagnostic devices for exhaust-gas treatment apparatus F01N11/00; conjoint electrical control of two or more combustion engine functions F02D43/00
• CPC Class Codes: F02D 2200/0812 Particle filter loading
• CPC Class Codes: F02D 31/002 controlling air supply
• CPC Class Codes: F02D 41/0205 using an auxiliary engine speed control engine speed control per se F02D31/00
• CPC Class Codes: F02D 41/024 to increase temperature of the exhaust gas treating apparatus
• CPC Class Codes: F02D 41/029 the exhaust gas treating apparatus being a particulate filter
• CPC Class Codes: F02N 2200/026 Catalyst temperature
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A catalyst heating system includes a monitoring module, a mode selection module and an electrically heated catalyst (EHC) control module. The monitoring module monitors at least one of (i) a first temperature of a non-EHC of a catalyst assembly in an exhaust system of an engine and (ii) an active catalyst volume of the catalyst assembly. The mode selection module is configured to select an EHC heating mode and generate a mode signal based on the at least one of the first temperature and the active catalyst volume. The EHC control module controls current to an EHC of the catalyst assembly based on the mode signal.

Claims

1. A catalyst heating system comprising:

a first monitoring module that monitors at least one of (i) a first temperature of a non-electrically heated catalyst (EHC) of a catalyst assembly in an exhaust system of an engine and (ii) an active catalyst volume of the catalyst assembly;

a mode selection module configured to select an EHC heating mode and generate a mode signal based on the at least one of the first temperature and the active catalyst volume; and

an EHC control module that controls current to an EHC of the catalyst assembly based on the mode signal.

2. The catalyst heating system of claim 1, further comprising:

a second monitoring module that monitors a second temperature of the EHC,

wherein the mode selection module is configured to select an engine speed maintaining mode and an air pumping mode and generates the mode signal based on the second temperature; and

an air pumping module that initiates at least one pumping action to pump air into an inlet of the catalyst assembly during the air pumping mode,

wherein the at least one pumping action includes (i) rotating a crankshaft of the engine when the engine is deactivated and (ii) activating an air pump.

3. The catalyst heating system of claim 2, wherein spark and fuel of the engine are disabled when the engine is deactivated.

4. The catalyst heating system of claim 2, further comprising a first comparison module that compares the active catalyst volume to a predetermined volume and generates a comparison signal,

wherein the mode selection module selects the air pumping mode when the comparison signal indicates that the active catalyst volume is less than the predetermined volume.

5. The catalyst heating system of claim 2, further comprising a first comparison module that compares the first temperature to a catalyst light off temperature and generates a first comparison signal,

wherein the mode selection module selects the air pumping mode when the first comparison signal indicates that the first temperature is less than the light off temperature.

6. The catalyst heating system of claim 5, further comprising a second comparison module that compares the second temperature to a maximum EHC convection temperature and generates a second comparison signal,

wherein the mode selection module selects the air pumping mode when the second comparison signal indicates that the second temperature is greater than the maximum EHC convection temperature, and

wherein the mode selection module selects engine speed maintaining mode when the second comparison signal indicates that the second temperature is less than or equal to the maximum EHC convection temperature.

7. The catalyst heating system of claim 6, further comprising a third comparison module that compares the second temperature to a minimum EHC convection temperature and generates a second comparison signal,

wherein the mode selection module selects the engine speed maintaining mode when the second comparison signal indicates that the second temperature is less than the minimum EHC convection temperature, and

wherein the mode selection module selects air pumping mode when the second comparison signal indicates that the second temperature is greater than or equal to the minimum EHC convection temperature.

8. The catalyst heating system of claim 2, further comprising the catalyst assembly, wherein the catalyst assembly comprises:

the non-EHC; and

an EHC upstream from the non-EHC, and

wherein the EHC control module transfers heat from the EHC to the non-EHC during the air pumping mode.

9. The catalyst heating system of claim 2, wherein the EHC control module activates the air pump to pump ambient air into the exhaust system upstream from the catalyst assembly during the air pumping mode.

10. The catalyst heating system of claim 2, wherein the mode selection module is configured to select the air pumping mode when an engine speed is less than a predetermined speed.

11. The catalyst heating system of claim 2, wherein the EHC control module controls operation of an electric motor to:

prevent the crankshaft from rotating during the engine speed maintaining mode; and

permit the crankshaft to rotate during the air pumping mode.

12. The catalyst heat system of claim 1, wherein the first monitoring module estimates the at least one of the first temperature and the active catalyst volume based on an engine speed, a flow rate, and at least one of a current and voltage of the EHC.

13. A catalyst heating system comprising:

a first monitoring module that monitors a first temperature of a non-electrically heated catalyst (EHC) of a catalyst assembly in an exhaust system of an engine;

a second monitoring module that monitors a second temperature of an EHC of the catalyst assembly;

a mode selection module configured to select an engine speed maintaining mode and an air pumping mode and generates a mode signal based on the first temperature and the second temperature; and

an air pumping module that initiates at least one pumping action to pump air into an inlet of the catalyst assembly during the air pumping mode,

wherein the at least one pumping action includes (i) rotating a crankshaft of the engine when the engine is deactivated and (ii) activating an air pump.

14. The catalyst heating system of claim 13, further comprising a first comparison module that compares the first temperature to a catalyst light off temperature and generates a first comparison signal,

wherein the mode selection module selects the air pumping mode when the first comparison signal indicates that the first temperature is less than the light off temperature.

15. The catalyst heating system of claim 14, further comprising a second comparison module that compares the second temperature to a maximum ENG convection temperature and generates a second comparison signal,

wherein the mode selection module selects the air pumping mode when the second comparison signal indicates that the second temperature is greater than the maximum EHC convection temperature, and

wherein the mode selection module selects engine speed maintaining mode when the second comparison signal indicates that the second temperature is less than or equal to the maximum EHC convection temperature.

16. The catalyst heating system of claim 15, further comprising a third comparison module that compares the second temperature to a minimum EHC convection temperature and generates a second comparison signal,

wherein the mode selection module selects the engine speed maintaining mode when the second comparison signal indicates that the second temperature is less than the minimum EHC convection temperature, and

wherein the mode selection module selects air pumping mode when the second comparison signal indicates that the second temperature is greater than or equal to the minimum EHC convection temperature.

17. A method of operating a catalyst heating system comprising:

monitoring at least one of (i) a first temperature of a non-electrically heated catalyst (EHC) of a catalyst assembly in an exhaust system of an engine and (ii) an active catalyst volume of the catalyst assembly;

selecting an EHC heating mode and generating a mode signal based on the at least one of the first temperature and the active catalyst volume; and

controlling current to an EHC of the catalyst assembly based on the mode signal.

18. The method of claim 17, further comprising:

monitoring a second temperature of the EHC;

selecting an engine speed maintaining mode and an air pumping mode and generating the mode signal based on the second temperature; and

initiating at least one pumping action to pump air into an inlet of the catalyst assembly during the air pumping mode,

wherein the at least one pumping action includes (i) rotating a crankshaft of the engine when the engine is deactivated and (ii) activating an air pump.

19. The method of claim 18, further comprising:

comparing the active catalyst volume to a predetermined volume and generating a comparison signal; and

selecting the air pumping mode when the comparison signal indicates that the first active catalyst volume is less than the predetermined volume.

20. The method of claim 18, further comprising:

comparing the first temperature to a catalyst light off temperature and generating a comparison signal; and

selecting the air pumping mode when the comparison signal indicates that the first temperature is less than the light off temperature.