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Method, system, and controller for determining a temperature set point for use in controlling regeneration of a particulate filter. The method, system, and controller being applicable in systems having an engine which emits exhaust gases having particulates which are captured by the particulate filt

Method, system, and controller for determining a temperature set point for use in controlling regeneration of a particulate filter. The method, system, and controller being applicable in systems having an engine which emits exhaust gases having particulates which are captured by the particulate filter.

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What is claimed is: 1. A method for determining a particulate filter temperature set point (Tset) value for a particulate filter, wherein the Tset value is used to control regeneration of particulates captured by the particulate filter, the method comprising: determining a critical temperature (Tc)

What is claimed is: 1. A method for determining a particulate filter temperature set point (Tset) value for a particulate filter, wherein the Tset value is used to control regeneration of particulates captured by the particulate filter, the method comprising: determining a critical temperature (Tc) value for the filter, the Tc value corresponding with a maximum temperature to which the filter may be desirably exposed during regeneration before risking heat damage; determining a temperature adjustment (Ta) value for the filter, the Ta value reflecting thermal inertia of the filter during regeneration; determining the Tset value as a function of the Tc and Ta values; and determining the Tc value as a function of filter geometries and filter material properties including: determining a decreasing value of Tc if oxygen concentration in the exhaust gases increases; determining an increasing value of Tc if oxygen concentration in the exhaust gases decreases; determining a decreasing value of Tc if the soot accumulation increases; and determining an increasing value of Tc if the soot accumulation decreases. 2. The method of claim 1 further comprising determining a decreasing value of Tc if the space velocity increases. 3. The method of claim 1 further comprising determining an increasing value of Tc if the space velocity decreases. 4. A method for determining a particulate filter temperature set point (Tset) value for a particulate filter, wherein the Tset value is used to control regeneration of particulates captured by the particulate filter, the method comprising: determining a critical temperature (Tc) value for the filter, the Tc value corresponding with a maximum temperature to which the filter may be desirably exposed during regeneration before risking heat damage; determining a temperature adjustment (Ta) value for the filter, the Ta value reflecting thermal inertia of the filter during regeneration; determining the Tset value as a function of the Tc and Ta values; and determining the Tc value from a Tc value lookup table which correlates Tc values according to a first ratio and a second ratio, the first ratio characterized by soot accumulation of the filter and exhaust space velocity through a particulate canister and the second ratio characterized by exhaust gas oxygen concentration and thermal characteristics of the filter. 5. The method of claim 4 wherein the first ratio is defined as C/V wherein V is exhaust space velocity and C is soot mass accumulation of the filter. 6. The method of claim 4 wherein the first ratio is defined as: description="In-line Formulae" end="lead"O2fraction {dot over (M)}exhCPexhRthermal({dot over (M)}exhCPexh Rthermal+1)description="In-line Formulae" end="tail" wherein 02fraction is oxygen concentration of the exhaust gas at an inlet of the particulate canister, Mexh is mass flow rate of the exhaust gases, Cpexh is heat capacity of the exhaust gases, and Rthermal is thermal resistance of the filter. 7. A method for determining a particulate filter temperature set point (Tset) value for a particulate filter, wherein the Tset value is used to control regeneration of particulates captured by the particulate filter, the method comprising: determining a critical temperature (Tc) value for the filter, the Tc value corresponding with a maximum temperature to which the filter may be desirably exposed during regeneration before risking heat damage; determining a temperature adjustment (Ta) value for the filter, the Ta value reflecting thermal inertia of the filter during regeneration; determining the Tset value as a function of the Tc and Ta values; and determining the Ta value according to the following formula: wherein, Rthermal is thermal resistance of the filter, Cpexh is exhaust gas heat capacity, Mexh is exhaust gas mass flow, Ti is exhaust gas temperature at an inlet through which the exhaust gases enter a particulate canister, and Tf is temperature of the particulate filter. 8. A method for determining a particulate filter temperature set point (Tset) value for a particulate filter, wherein the Tset value is used to control regeneration of particulates captured by the particulate filter, the method comprising: determining a critical temperature (Tc) value for the filter, the Tc value corresponding with a maximum temperature to which the filter may be desirably exposed during regeneration before risking heat damage; determining a temperature adjustment (Ta) value for the filter, the Ta value reflecting thermal inertia of the filter during regeneration; determining the Tset value as a function of the Tc and Ta values comprising; and determining Tset to be greater than the Tc value if the Ta value indicates the thermal inertia of the filter is below a thermal inertia threshold, the thermal inertia threshold corresponding with a desired rate of temperature of increase for the filter. 9. The method of claim 8 wherein the Ta value indicates the filter rate of temperature change is below the thermal inertia threshold if a temperature at an inlet through which the exhaust gases flow into the particulate canister is less than a temperature of the filter. 10. A method for determining a particulate filter temperature set point (Tset) value for a particulate filter, wherein the Tset value is used to control regeneration of particulates captured by the particulate filter, the method comprising: determining a critical temperature (Tc) value for the filter, the Tc value corresponding with a maximum temperature to which the filter may be desirably exposed during regeneration before risking heat damage; determining a temperature adjustment (Ta) value for the filter, the Ta value reflecting thermal inertia of the filter during regeneration; and determining the Tset value as a function of the Tc and Ta values; and determining Tset to be less than the Tc value if the Ta value indicates the thermal inertia of the filter is greater than a thermal inertia threshold, the thermal inertia threshold corresponding with a desired rate of temperature of increase for the filter. 11. The method of claim 10 wherein the Ta value indicates the filter rate of temperature change is greater than the thermal inertia threshold if a temperature at an inlet through which the exhaust gases flow into the particulate canister is greater than a temperature of the filter.