Apparatus and method for accelerated exhaust system component heating
Accelerated heating of automotive exhaust system components is effected by controlling the application of supplemental electrical loads to the vehicle electrical system thereby increasing engine load and increasing exhaust heat. Alternative strategies are disclosed for implementing the invention through control of electrical and engine management system parameters.
1. Apparatus for cold start heating of exhaust system components in an automobile comprising an internal combustion engine including an engine controller effective to control engine speed by adjusting the engine load operating point comprising:
a generator driven by the internal combustion engine and providing a regulated output therefrom; and,
a controller adapted for determining when cold start heating of exhaust system components is required and effective to electrically couple a supplemental electrical load to the regulated output from the generator to increase engine heat output when cold start heating of exhaust system components is required.
2. The apparatus as claimed in claim 1 wherein said supplemental electrical load comprises a resistive load.
3. The apparatus as claimed in claim 2 wherein said supplemental electrical load seen by the generator is variable.
4. The apparatus as claimed in claim 3 wherein said supplemental electrical load comprises means for PWM control of the resistive load.
5. The apparatus as claimed in claim 2 wherein said supplemental electrical load comprises a preexisting vehicle electrical load.
6. The apparatus as claimed in claim 5 wherein said supplemental electrical load seen by the generator is variable.
7. The apparatus as claimed in claim 6 wherein said supplemental electrical load comprises means for PWM control of the resistive load.
8. The apparatus as claimed in claim 2 wherein said resistive load is selected from the group consisting of a power resistor, a rheostat, an engine block heater, an engine coolant heater, an engine intake air heater, an engine fuel heater, an exhaust gas sensor heater, a glass defroster, a seat heater and combinations thereof.
9. The apparatus as claimed in claim 8 wherein said supplemental electrical load seen by the generator is variable.
10. The apparatus as claimed in claim 1 wherein said controller is adapted for determining when cold start heating of exhaust system components is no longer required and effective to electrically decouple the supplemental electrical load from the output of the generator.
11. The apparatus as claimed in claim 1 wherein the generator is an alternator including an actively controlled bridge rectifier effective to controllably vary alternator output characteristics.
12. Method for cold start heating of exhaust system components in an automobile comprising an internal combustion engine, an engine controller and an electric generator drivingly coupled to the engine and having a regulated electrical output:
providing a supplemental electrical load to the regulated output to provide torque load to the engine; and,
controlling engine speed to a predetermined engine speed profile.
13. Method far cold start heating of exhaust system components as claimed in claim 12 wherein controlling engine speed to a predetermined engine speed profile comprises controlling engine speed through fuel charge adjustments.
14. Method for cold start heating of exhaust system components as claimed in claim 12 wherein controlling engine speed to a predetermined engine speed profile comprises controlling engine speed through supplemental electrical load adjustments.
15. Method for cold start heating of exhaust system components as claimed in claim 13 wherein said supplemental electrical load is provided in accordance with monitored generator parameters.
16. Method for cold start heating of exhaust system components as claimed in claim 13 wherein said supplemental electrical load is provided in accordance with a predetermined load profile.
17. Method for cold start heating of exhaust system components as claimed in claim 14 comprising controlling fuel charge in accordance with a predetermined fuel charge profile.
18. Method for cold start heating of exhaust system components as claimed in claim 12 further comprising retarding engine spark timing.
19. Apparatus for cold start heating of exhaust system components comprising:
an electrical generator having a regulated output coupled to nominal electrical loads;
an internal combustion engine drivingly coupled to the generator; and,
a computer based control operatively coupled to the internal combustion engine and generator, said control including a set of program instructions effective to coordinate engine fueling and generator electrical loading to control engine speed to a predetermined engine speed profile at greater than nominal engine loads.
20. The apparatus as claimed in claim 19 wherein the computer based control is selected from the group consisting of a powertrain controller, a vehicle body controller, and combinations thereof.
21. The apparatus as claimed in claim 19 wherein the electrical generator comprises an alternator including a field winding and a bridge rectifier, wherein said regulated output is regulated by field current control.
22. The apparatus as claimed in claim 21 wherein said bridge rectifier comprises a controlled bridge rectifier, and wherein said regulated output is additionally regulated by power factor control.