Aftertreatment heat up strategies
A method of controlling temperature of an engine aftertreatment system includes directing an electric heater in the engine aftertreatment system to apply heat using a first temperature setpoint; while applying the heat at the first temperature setpoint, receiving temperature data from a temperature sensor proximate to a selective catalytic reduction (SCR) device in the engine aftertreatment system; determining from the temperature data that a first temperature is at a first threshold temperature which is less than the first temperature setpoint; and after determining that the first temperature is at the first threshold temperature, directing the electric heater to apply heat using a second temperature setpoint which is less than the first temperature setpoint.
1. A method of controlling temperature of an engine aftertreatment system, comprising:
directing an electric heater in the engine aftertreatment system to apply heat using a first temperature setpoint;
while applying the heat at the first temperature setpoint, receiving temperature data from a temperature sensor proximate to a selective catalytic reduction (SCR) device in the engine aftertreatment system;
determining from the temperature data that a first temperature is at a first threshold temperature which is less than the first temperature setpoint; and
after determining that the first temperature is at the first threshold temperature, directing the electric heater to apply heat using a second temperature setpoint which is less than the first temperature setpoint.
2. The method of claim 1 , wherein the electric heater is upstream from the SCR device.
3. The method of claim 2 , wherein the SCR device is a light off SCR (LO-SCR).
4. The method of claim 3 , wherein the temperature sensor is located at an SCR mid-bed.
5. The method of claim 2 , wherein the SCR device is a primary SCR.
6. The method of claim 1 , wherein the first temperature setpoint is within a range of 300-400° C. and the second temperature setpoint is within a range of 190-200° C.
7. The method of claim 1 , wherein the first threshold temperature is 300° C.
8. The method of claim 1 , wherein the first temperature setpoint is within a range of 200-275° C. and the second temperature setpoint is within a range of 190-200° C.
9. The method of claim 1 , wherein the heat applied at the first temperature setpoint is applied using the temperature data from a SCR inlet temperature, a SCR mid-bed temperature, SCR average temperature, a diesel particulate filter (DPF) outlet temperature, or a diesel oxidation catalyst (DOC) outlet temperature.
10. The method of claim 1 , wherein the temperature sensor is located at a SCR inlet, SCR mid-bed, a DPF outlet, or a DOC outlet.
11. The method of claim 1 , further comprising:
while applying the heat at the second temperature setpoint, receiving second temperature data from the temperature sensor proximate to the SCR device in the engine aftertreatment system; and
determining from the second temperature data that a second temperature is at a second threshold temperature which is less than the second temperature setpoint.
12. The method of claim 11 , further comprising after determining that the second temperature is at the second threshold temperature, directing the electric heater to turn off.
13. The method of claim 11 , further comprising after determining that the second temperature is at the second threshold temperature, directing the electric heater to apply heat using a third temperature setpoint which is less than the second temperature setpoint.
14. The method of claim 11 , wherein the first threshold temperature is 275° C. and the second threshold temperature is 285° C.
15. The method of claim 11 , wherein the first threshold temperature is 275° C. and the second threshold temperature is 240° C.
16. The method of claim 1 , further comprising running an engine coupled to the engine aftertreatment system in “elevated idle” mode.
17. The method of claim 16 , further comprising running the engine in cylinder deactivation (CDA) mode.
18. The method of claim 1 , further comprising directing the electric heater to turn off.