# US 10,371,035 B2 · Method and system at supply of additive to an exhaust gas stream > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,035 B2 - Document ID: US10371035B2 - Status: Granted - Kind: B2 - Application number: 15/110,300 - Filed: 2015-01-29 - Published: 2016-11-10 - Granted: 2019-08-06 - Earliest claimed: 2014-01-31 - Assignees: Scania CV AB - Applicants: Scania Cv AB - Inventors: Christer Lundberg - Web page: https://patentgrep.com/patent/US10371035B2 ## CPC - F01N 9/005: {using models instead of sensors to determine operating characteristics of exhaust systems, e.g. calculating catalyst temperature instead of measuring it directly} - F01N 3/208: {Control of selective catalytic reduction [SCR], e.g. by adjusting the dosing of reducing agent} - 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) - F01N 2560/026: for measuring or detecting NOx - F01N 2560/14: having more than one sensor of one kind - F01N 2610/02: the substance being ammonia or urea - Y02A 50/20: Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters - Y02T 10/12: Improving ICE efficiencies - Y02T 10/40: Engine management systems - F01N: GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES (arrangements in connection with gas exhaust of propulsion units in vehicles B60K13/00; combustion-air intake silencers specially adapted for, or arranged on, internal-combustion engines F02M35/00; protecting against, or damping, noise in general G10K11/16) - Y02A: TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract The present invention concerns a method in connection with the supplying of a first additive for treating an exhaust gas stream resulting from combustion in a combustion engine, wherein said first additive is supplied to said exhaust gas stream, and wherein said first additive is utilized for the reduction of at least a first substance (such as NOx) present in said exhaust gas stream, wherein the method comprises: estimation of a reduction of said first substance based on a first measurement of a presence of said first substance in said exhaust gas stream downstream of said supply of said first additive, and a second measurement of a presence of said first substance in said exhaust gas stream upstream of said supply of additive, comparison of said estimated reduction to a first reduction, and correction of the estimation of said second measurement of said first substance based on said comparison. ## Claims ### Claim 1 A method in connection with the supplying of a first additive for treating an exhaust gas stream resulting from combustion in a combustion engine, wherein said first additive is supplied to said exhaust gas stream, and wherein said first additive is utilized to reduce at least a first substance, wherein said method comprises: supplying a first additive to the exhaust gas stream; estimating a reduction of said first substance based on a first measurement of a presence of said first substance in said exhaust gas stream downstream of said supply of said first additive, and a second measurement of a presence of said first substance in said exhaust gas stream upstream of said supply of additive; comparing said estimated reduction with a first reduction; and correcting said second measurement of said first substance based on said comparison. ### Claim 2 (depends on 1) A method according to claim 1, further comprising: determining said first measurement by utilization of signals emitted by a first sensor arranged downstream of said supply of said first additive. ### Claim 3 (depends on 2) A method according claim 2, wherein said second measurement consists of an estimated measurement, wherein said correction of said second measurement constitutes a correction of an estimation of said second measurement. ### Claim 4 (depends on 1) A method according to claim 1, wherein said second measurement is estimated through the utilization of a calculation model. ### Claim 5 (depends on 4) A method according to claim 4, wherein said calculation model consists at least in part of a model of the combustion in said combustion engine. ### Claim 6 (depends on 1) A method according to claim 1, further comprising, based on said comparison of said estimated reduction with said first reduction: determining a correction factor for correcting the estimation of said second measurement. ### Claim 7 (depends on 1) A method according to claim 1, further comprising: correcting the estimation of said second measurement when said estimated reduction is below said first reduction so that the estimated presence of said first substance after correction exceeds the estimated presence without correction; and/or correcting the estimation of said second measurement when said estimated reduction exceeds said first reduction so that the estimated presence of said first substance after correction is below the estimated presence without correction. ### Claim 8 (depends on 1) A method according to claim 1, further comprising: performing a first accumulation of a representation of said first substance downstream of said supply of additive during a first time; performing a second accumulation of a representation of said first substance upstream of said supply of additive during said first time; and estimating said reduction of said first substance based on said first and second accumulation. ### Claim 9 (depends on 8) A method according to claim 8, further comprising: estimating said reduction of said first substance by determining a ratio between said first accumulation and said second accumulation; comparing said determined ratio to a first ratio; and correcting the estimation of said second measurement based on said comparison. ### Claim 10 (depends on 8) A method according to claim 8, further comprising, when said first accumulation and said second accumulation have been initiated: determining whether a first amount of work has been performed by said combustion engine during the accumulation of said first substance; and discontinuing the accumulation of said first substance once said first amount of work has been performed by said combustion engine. ### Claim 11 (depends on 1) A method according to claim 1, wherein said first additive is supplied upstream of a first catalytic converter, and wherein said presence of said first substance in said exhaust gas stream downstream of said supply of said first additive consists of a presence of said first substance downstream of said first catalytic converter. ### Claim 12 (depends on 10) A method according to claim 10, wherein said first catalytic converter consists of an SCR catalytic converter. ### Claim 13 (depends on 1) A method according to claim 1, further comprising, before said estimation of said reduction of said first substance: reducing the supply of additive to a first amount, wherein said first amount consists of an amount corresponding to a reduction at which a smaller amount of additive is supplied than is needed for a complete reduction of said first substance, wherein said first reduction corresponds to the anticipated reduction in connection with the supply of said first amount. ### Claim 14 (depends on 12) A method according to claim 12, wherein said first amount consists of an amount at which the anticipated conversion rate for the reduction of said first substance maximally equals any of the conversion rates comprising: 90% of complete reduction, 80% of complete reduction, 50% of complete reduction. ### Claim 15 (depends on 12) A method according to claim 12, further comprising, before said estimation of said reduction: reducing the supply of said first additive to said first amount; and initiating said estimation of said reduction a first time after said supply of said first additive has been reduced. ### Claim 16 (depends on 12) A method according to claim 12, further comprising: determining whether a second amount of work has been performed by said combustion engine after the reduction of said supply of said first additive was initiated; and initiating said estimation of said reduction when said second amount of work has been performed by said combustion engine. ### Claim 17 (depends on 12) A method according to claim 12, further comprising: discontinuing reduction of said supply of said first additive when said second measurement has been corrected. ### Claim 18 (depends on 1) A method according to claim 1, wherein said first reduction consists of an anticipated, or set, reduction. ### Claim 19 (depends on 1) A method according to claim 1, wherein said supply of additive is controlled so that the anticipated reduction consists of said first reduction. ### Claim 20 (depends on 1) A method according to claim 1, further comprising control of the supply of first additive based on said corrected second measurement. ### Claim 21 A vehicle comprising a system for use in connection with the supplying of a first additive for treating an exhaust gas stream resulting from combustion in a combustion engine, wherein said first additive is supplied to said exhaust gas stream, and wherein said first additive is used to reduce at least a first substance present in said exhaust gas stream, wherein the system comprises elements configured to: estimate a reduction of said first substance based on a first measurement of a presence of said first substance in said exhaust gas stream downstream of said supply of said first additive, and a second measurement of a presence of said first substance in said exhaust gas stream upstream of said supply of additive; compare said estimated reduction to a first reduction; and correct said second measurement of said first substance based on said comparison. ### Claim 22 A computer program for use in connection with the supplying of a first additive for treating an exhaust gas stream resulting from combustion in a combustion engine, wherein said first additive is supplied to said exhaust gas stream, and wherein said first additive is used to reduce at least a first substance present in said exhaust gas stream, wherein the computer program product is stored in a non-transitory computer-readable medium and comprises computer-readable program code portions embodied therein, the computer-readable program code portions configured to cause an electronic processor to: supply a first additive to the exhaust gas stream; estimate a reduction of said first substance based on a first measurement of a presence of said first substance in said exhaust gas stream downstream of said supply of said first additive, and a second measurement of a presence of said first substance in said exhaust gas stream upstream of said supply of additive; compare said estimated reduction to a first reduction; and correct said second measurement of said first substance based on said comparison. ### Claim 23 A system for use in connection with the supplying of a first additive for treating an exhaust gas stream resulting from combustion in a combustion engine, wherein said first additive is supplied to said exhaust gas stream, and wherein said first additive is used to reduce at least a first substance present in said exhaust gas stream, wherein the system comprises elements configured to: estimate a reduction of said first substance based on a first measurement of a presence of said first substance in said exhaust gas stream downstream of said supply of said first additive, and a second measurement of a presence of said first substance in said exhaust gas stream upstream of said supply of additive; compare said estimated reduction to a first reduction; and correct said second measurement of said first substance based on said comparison.