US 2022/0090529 A1Published application

Systems and methods for implementing corrections to a reductant delivery system in an exhaust aftertreatment system of an internal combustion engine

AssigneeCummins Emission Solutions Inc.

InventorsJinqian Gong, Arun Kumar Dasari, Gautam Sharma

Life of this patent

Estimating the term…

Loading patent…

Abstract

An exhaust aftertreatment system includes a catalyst, an exhaust conduit system, a first sensor, a second sensor, a reductant pump, a dosing module, and a reductant delivery system controller. The exhaust conduit system is coupled to the catalyst. The first sensor is coupled to the exhaust conduit system upstream of the catalyst and configured to obtain a current first measurement upstream of the catalyst. The second sensor is coupled to the exhaust conduit system downstream of the catalyst and configured to obtain a current second measurement downstream of the catalyst. The reductant pump is configured to draw reductant from a reductant source. The dosing module is fluidly coupled to the reductant pump and configured to selectively provide the reductant from the reductant pump into the exhaust conduit system upstream of the catalyst. The reductant delivery system controller is communicable with the first sensor, the second sensor, the reductant pump, and the dosing module.

Claims20

Dependent claims

An exhaust aftertreatment system comprising:

a catalyst;
an exhaust conduit system coupled to the catalyst;
a first sensor coupled to the exhaust conduit system upstream of the catalyst and configured to obtain a current first measurement upstream of the catalyst;
a second sensor coupled to the exhaust conduit system downstream of the catalyst and configured to obtain a current second measurement downstream of the catalyst;
a reductant pump configured to draw reductant from a reductant source;
a dosing module fluidly coupled to the reductant pump and configured to selectively provide the reductant from the reductant pump into the exhaust conduit system upstream of the catalyst;
and
a reductant delivery system controller communicable with the first sensor, the second sensor, the reductant pump, and the dosing module, the reductant delivery system controller configured to:
receive and store the current first measurement from the first sensor,
receive and store the current second measurement from the second sensor,
cause the reductant pump to draw the reductant at a first rate,
cause the dosing module to provide a first amount of the reductant,
determine a current conversion efficiency based on the current first measurement and the current second measurement,
store the current conversion efficiency,
determine a current low conversion efficiency time based on the current conversion efficiency,
determine a current bias index based on the current low conversion efficiency time,
compare the current bias index to a bias index threshold, and
adjust at least one of the first rate or the first amount when the current bias index is greater than the bias index threshold.

15 more elements

An exhaust aftertreatment system comprising:

a catalyst;
a first sensor configured to obtain a current first measurement upstream of the catalyst;
a second sensor configured to:
obtain a current second measurement downstream of the catalyst;
and obtain, prior to obtaining the current second measurement, a previous second measurement downstream of the catalyst;
a reductant pump configured to draw reductant from a reductant source;
a dosing module fluidly coupled to the reductant pump and configured to selectively provide the reductant from the reductant pump upstream of the catalyst;
and
a reductant delivery system controller communicable with the first sensor, the second sensor, the reductant pump, and the dosing module, the reductant delivery system controller configured to:
receive and store the previous second measurement from the second sensor,
receive and store the current first measurement from the first sensor,
receive and store the current second measurement from the second sensor,
cause the reductant pump to draw the reductant at a first rate,
cause the dosing module to provide a first amount of the reductant,
determine a current conversion efficiency based on the current first measurement and the current second measurement,
store the current conversion efficiency,
determine a current low conversion efficiency time based on the current conversion efficiency,
determine an average second measurement differential based on the current second measurement and the previous second measurement,
compare an absolute value of the average second measurement differential to a second measurement spike initial threshold,
increase a positive bias counter in response to the absolute value of the average second measurement differential not being greater than the second measurement spike initial threshold,
compare the absolute value of the average second measurement differential to a second measurement spike secondary threshold in response to the absolute value of the average second measurement differential not being greater than the second measurement spike initial threshold,
increase a negative bias counter in response to the absolute value of the average second measurement differential not being less than the second measurement spike secondary threshold,
determine a current bias index based on the negative bias counter and at least one of:
the current low conversion efficiency time or the positive bias counter,
compare the current bias index to a bias index threshold, and
adjust at least one of the first rate or the first amount when the current bias index is greater than the bias index threshold.

23 more elements

An exhaust aftertreatment system comprising:

a catalyst;
a first sensor configured to obtain a current first measurement upstream of the catalyst;
a second sensor configured to obtain a current second measurement downstream of the catalyst;
a catalyst temperature sensor coupled to the catalyst and configured to obtain a temperature of the catalyst;
a reductant pump configured to draw reductant from a reductant source;
a dosing module fluidly coupled to the reductant pump and configured to selectively provide the reductant from the reductant pump upstream of the catalyst;
and
a reductant delivery system controller communicable with the first sensor, the second sensor, the catalyst temperature sensor, the reductant pump, and the dosing module, the reductant delivery system controller configured to:
cause the reductant pump to draw the reductant at a first rate,
cause the dosing module to provide a first amount of the reductant,
receive and store the current first measurement from the first sensor,
receive and store the current second measurement from the second sensor,
determine that the first sensor is obtaining the current first measurement,
determine that the second sensor is obtaining the current second measurement,
compare the catalyst temperature to a target catalyst temperature range, and
after determining that (i) the first sensor is obtaining the current first measurement, (ii) the second sensor is obtaining the current second measurement, and (iii) the catalyst temperature is within the target catalyst temperature range, determine a current conversion efficiency based on the current first measurement and the current second measurement;
store the current conversion efficiency, and
adjust at least one of the first rate or the first amount based on the current conversion efficiency.

15 more elements

Dependencies are inferred from the claim text.

Facts

Application: 17/424,462Filed 10 Jan 2020
Priority: 22 Jan 2019
Published: 24 Mar 2022
Term ends: Not estimatedThe source records don’t support an estimate.

Classification21 codes

F01N 3/208
Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing…:…
F01N 3/021
For cooling, or for removing solid constituents of, exhaust: by means of filters
F01N 3/035
In combination with other devices: with catalytic reactors
F01N 3/10
For rendering innocuous: by thermal or catalytic conversion of noxious components of exhaust