# US 8,769,932 B2 · Cold start NO2 generation system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,769,932 B2 - Document ID: US8769932B2 - Status: Granted - Kind: B2 - Application number: 13/272,696 - Filed: 2011-10-13 - Published: 2013-04-18 - Granted: 2014-07-08 - Earliest claimed: 2011-10-13 - Assignees: GM Global Technology Operations LLC - Applicants: Eugene V. Gonze; Michael J. Paratore, Jr.; Chang H. Kim; Steven J. Schmieg - Inventors: Eugene V. Gonze; Michael J. Paratore, Jr.; Chang H. Kim; Steven J. Schmieg - Web page: https://patentgrep.com/patent/US8769932B2 ## CPC - F01N 3/101: {Three-way catalysts} - F01N 3/103: {Oxidation catalysts for HC and CO only} - F01N 3/2066: {Selective catalytic reduction [SCR]} - F01N 3/2073: {Means for generating a reducing substance from the exhaust gases} - F01N 13/0093: {the purifying devices are of the same type} - F02D 41/0235: {in relation with the state of the exhaust gas treating apparatus (control of exhaust gas treating apparatus per se F01N)} - F02D 2200/0802: Temperature of the exhaust gas treatment apparatus - Y02T 10/12: Improving ICE efficiencies - 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) - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A cold start NO2 generation system includes a catalyst control module that identifies a portion of a three-way catalyst that corresponds to a nitrogen dioxide zone. A diagnostic module determines a temperature in the nitrogen dioxide zone, and a fuel control module adjusts an air/fuel ratio based on the temperature in the nitrogen dioxide zone. A cold start NO2 generation method includes identifying a portion of a three-way catalyst that corresponds to a nitrogen dioxide zone. The method further includes determining a temperature in the nitrogen dioxide zone and adjusting an air/fuel ratio based on the temperature in the nitrogen dioxide zone. ## Claims ### Claim 1 A system comprising: a first electronic circuit configured to determine a portion of a three-way catalyst that corresponds to a first zone and a portion of the three-way catalyst that corresponds to a second zone, wherein the first zone corresponds to a hydrocarbon zone and the second zone corresponds to a nitrogen dioxide zone, and wherein the first zone is positioned before the second zone in the three way catalyst such that a fluid flowing through the three-way catalyst flows through the first zone before flowing through the second zone; a second electronic circuit configured to determine a temperature in the nitrogen dioxide zone; and a third electronic circuit configured to adjust an air/fuel ratio based on the temperature in the nitrogen dioxide zone. ### Claim 2 (depends on 1) The system of claim 1, wherein the second electronic circuit is configured to determine whether an engine is operating in a cold start mode, wherein the engine is operating in the cold start mode if a coolant temperature is below a predetermined temperature threshold. ### Claim 3 (depends on 2) The system of claim 2, wherein the first electronic circuit is configured to identify a state of a selective catalytic reduction system if the engine is not operating in the cold start mode. ### Claim 4 (depends on 1) The system of claim 1, wherein the second electronic circuit is configured to determine an exhaust temperature in the three-way catalyst. ### Claim 5 (depends on 4) The system of claim 4, wherein the third electronic circuit is configured to operate an engine in a catalyst warm up mode if the exhaust temperature is less than a predetermined temperature threshold. ### Claim 6 (depends on 4) The system of claim 4, wherein the third electronic circuit is configured to operate an engine in an active lean operation mode if the exhaust temperature is greater than a predetermined temperature threshold. ### Claim 7 (depends on 6) The system of claim 6, wherein the first electronic circuit is configured to discontinue use of the three-way catalyst if the engine operates in the active lean operation mode. ### Claim 8 (depends on 1) The system of claim 1, wherein the first electronic circuit is configured to identify a state of a selective catalytic reduction system. ### Claim 9 (depends on 1) The system of claim 1, wherein a size of the hydrocarbon zone is a function of a hydrocarbon level, an exhaust flow level, and an exhaust temperature. ### Claim 10 (depends on 1) The system of claim 1, wherein the nitrogen dioxide zone converts nitric oxide to nitrogen dioxide. ### Claim 11 (depends on 1) The system of claim 1, wherein the third electronic circuit is configured to increase the air/fuel ratio by a nitrogen dioxide correction factor if the temperature in the nitrogen dioxide zone is greater than a predetermined temperature threshold. ### Claim 12 (depends on 1) The system of claim 1, wherein the third electronic circuit is configured to decrease the air/fuel ratio by a nitrogen dioxide correction factor if the temperature in the nitrogen dioxide zone is less than a predetermined temperature threshold. ### Claim 13 (depends on 1) The system of claim 1, wherein the first electronic circuit and the third electronic circuit are configured to control a selective catalytic reduction system temperature to maintain a thermally active state in a selective catalytic reduction system by increasing or decreasing the air/fuel ratio. ### Claim 14 (depends on 13) The system of claim 13, wherein the second electronic circuit is configured to determine the temperature in the nitrogen dioxide zone if the selective catalytic reduction system is not in the thermally activated state. ### Claim 15 A method comprising: determininq a portion of a three-way catalyst that corresponds to a first zone and a portion of the three-way catalyst that corresponds to a second zone, wherein the first zone corresponds to a hydrocarbon zone and the second zone corresponds to a nitrogen dioxide zone; wherein the hydrocarbon zone is positioned before the nitrogen dioxide zone in the three way catalyst, such that a fluid flowing through the three-way catalyst flows through the hydrocarbon zone before flowing through the nitrogen dioxide zone, determining a temperature in the nitrogen dioxide zone; and adjusting an air/fuel ratio based on the temperature in the nitrogen dioxide zone. ### Claim 16 (depends on 15) The method of claim 15, further comprising determining whether an engine is operating in a cold start mode, wherein the engine is operating in a cold start mode if a coolant temperature is below a predetermined temperature threshold. ### Claim 17 (depends on 16) The method of claim 16, further comprising identifying a state of a selective catalytic reduction system if the engine is not operating in the cold start mode. ### Claim 18 (depends on 15) The method of claim 15, further comprising determining an exhaust temperature in the three-way catalyst. ### Claim 19 (depends on 18) The method of claim 18, further comprising operating an engine in a catalyst warm up mode if the exhaust temperature is less than a predetermined temperature threshold. ### Claim 20 (depends on 18) The method of claim 18, further comprising operating an engine in an active lean operation mode if the exhaust temperature is greater than a predetermined temperature threshold. ### Claim 21 (depends on 20) The method of claim 20, further comprising discontinuing use of the three-way catalyst if the engine operates in the active lean operation mode. ### Claim 22 (depends on 15) The method of claim 15, further comprising identifying a state of a selective catalytic reduction system. ### Claim 23 (depends on 15) The method of claim 15, wherein a size of the hydrocarbon zone is a function of a hydrocarbon level, an exhaust flow level, and an exhaust temperature. ### Claim 24 (depends on 15) The method of claim 15, wherein the nitrogen dioxide zone converts nitric oxide to nitrogen dioxide. ### Claim 25 (depends on 15) The method of claim 15, further comprising increasing the air/fuel ratio by a nitrogen dioxide correction factor if the temperature in the nitrogen dioxide zone is greater than a predetermined temperature threshold. ### Claim 26 (depends on 15) The method of claim 15, further comprising decreasing the air/fuel ratio by a nitrogen dioxide correction factor if the temperature in the nitrogen dioxide zone is less than a predetermined temperature threshold. ### Claim 27 (depends on 15) The method of claim 15, further comprising controlling a selective catalytic reduction system temperature to maintain a thermally active state in a selective catalytic reduction system by increasing or decreasing the air/fuel ratio. ### Claim 28 (depends on 27) The method of claim 27, further comprising determining the temperature in the nitrogen dioxide zone if the selective catalytic reduction system is not in the thermally activated state.