# US 12,768,311 B2 · Systems and methods for migitating cold start emissions in a vehicle including a catalyst heater via rotation of a turbocharger turbine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,768,311 B2 - Document ID: US12768311B2 - Status: Granted - Kind: B2 - Application number: 18/904,961 - Filed: 2024-10-02 - Published: 2026-04-02 - Granted: 2026-10-20 - Earliest claimed: 2024-10-02 - Assignees: GM Global Technology Operations LLC - Applicants: GM Global Technology Operations LLC - Inventors: Azeem Sarwar; Mark Claywell; Maqsood Rizwan Ali Khan - Web page: https://patentgrep.com/patent/US12768311B2 ## CPC - F02D 41/064: {at cold start (F02D41/067 takes precedence)} - F01N 3/2006: {Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating (by electrically controlling the supply of combustible mixture or its constituents only F02D41/0235)} - F02D 41/0007: {for control of turbo-charged or super-charged engines (control of the pumps per se F02B37/12)} - 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) - 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) ## Abstract Control signals are issued to open a wastegate, rotate a turbine, and turn on a catalyst heater disposed between the turbine and a catalyst in response to a trigger signal. The rotation of the turbine causes recirculated air flow in a recirculation flow path including an exhaust manifold, exhaust walls between the exhaust manifold and the turbine, a turbine housing, exhaust walls between the turbine and the wastegate, exhaust walls between the wastegate and the exhaust manifold, and exhaust walls between the turbine and the catalyst heater. Heat is transferred from the recirculated air heated by the catalyst heater to the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing, the exhaust walls between the turbine and the wastegate, the exhaust walls between the wastegate and the exhaust manifold, and the exhaust walls between the turbine and the catalyst heater. ## Claims ### Claim 1 A method of mitigating cold start emissions in a vehicle including a catalyst heater via rotation of turbocharger turbine comprising: issuing, by the controller, a first command to a variable valve timing (VVT) system to at least partially open intake valves and exhaust valves of a plurality of cylinders of an engine during a previous shut down routine of the engine to enable air to flow from an intake system through the plurality of cylinders to an exhaust manifold; receiving, at a controller, a trigger signal from a trigger signal source of the vehicle, wherein an ignition system turns on the vehicle and does not start the engine in response to the trigger signal; issuing, by the controller, a second command to a wastegate actuator to open a wastegate responsive to the trigger signal; issuing, by the controller, a third command to an exhaust gas recirculation (EGR) valve actuator to open an EGR valve to enable the air to flow from the intake system to the exhaust manifold via the EGR valve in response to the trigger signal; issuing, by the controller, a fourth command to a turbo shaft actuator to rotate a turbine of a turbocharger responsive to the trigger signal, wherein rotation of the turbine occurs prior to the engine having any cylinder firing events; and issuing, by the controller, a fifth command to the catalyst heater to turn on the catalyst heater responsive to the trigger signal, the catalyst heater being disposed between the turbine and a first catalyst brick, wherein: the rotation of the turbine causes the air to flow in a recirculation flow path as recirculated air; the recirculation flow path comprises the exhaust manifold, exhaust walls between the exhaust manifold and the turbine, a turbine housing of the turbine, exhaust walls between the turbine and the wastegate, exhaust walls between the wastegate and the exhaust manifold, and exhaust walls between the turbine and the catalyst heater; the first catalyst brick is disposed outside the recirculation flow path; the recirculated air is heated by the catalyst heater; and heat is transferred from the heated recirculated air to the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the wastegate, the exhaust walls between the wastegate and the exhaust manifold, and the exhaust walls between the turbine and the catalyst heater prior to turning on the engine: The recirculation flow path comprises the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the catalyst heater, exhaust walls between the catalyst heater and a second catalyst brick, exhaust walls between the second catalyst brick and the wastegate, and the exhaust walls between the wastegate and the exhaust manifold; the second catalyst brick is disposed inside the recirculation flow path; and heat is transferred from the heated recirculated air to the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the catalyst heater, the exhaust walls between the catalyst heater and the second catalyst brick, the exhaust walls between the second catalyst brick and the wastegate, the exhaust walls between the wastegate and the exhaust manifold, and the second catalyst brick. ### Claim 2 (depends on 1) The method of claim 1, wherein issuing by the controller, the second command to the wastegate actuator to open the wastegate comprises issuing by the controller, the second command to the wastegate actuator to fully open the wastegate. ### Claim 3 (depends on 1) The method of claim 1, further comprising issuing, by the controller, a sixth command to a compressor bypass valve actuator to open a compressor bypass valve responsive to the trigger signal. ### Claim 4 (depends on 1) The method of claim 1, wherein: the recirculation flow path is adjacent a first side of the first catalyst brick; and heat is transferred from the heated recirculated air to the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the catalyst heater, the exhaust walls between the catalyst heater and the wastegate, the exhaust walls between the wastegate and the exhaust manifold, the exhaust walls between the catalyst heater and the first catalyst brick, and the first catalyst brick via the first side of the first catalyst brick. ### Claim 5 (depends on 1) The method of claim 1, wherein the first catalyst brick comprises an oxidation catalyst. ### Claim 6 (depends on 1) The method of claim 1, wherein the turbo shaft actuator is a motor generator unit (MGU). ### Claim 7 A system for mitigating cold start emissions generated by a vehicle including a catalyst heater via rotation of turbocharger turbine, comprising: at least one processor; and at least one memory communicatively coupled to the at least one processor, the at least one memory comprising instructions that upon execution by the at least one processor, causes the at least one processor to: issue a first command to a variable valve timing (VVT) system to at least partially open intake valves and exhaust valves of a plurality of cylinders of an engine during a previous shut down routine of the engine to enable air to flow from an intake system through the plurality of cylinders to an exhaust manifold; receive a trigger signal from a trigger signal source of the vehicle, wherein an ignition system turns on the vehicle and does not start the engine in response to the trigger signal; issue a second command to a wastegate actuator to open a wastegate responsive to the trigger signal; issue a third command to an exhaust gas recirculation (EGR) valve actuator to open an EGR valve to enable the air to flow from the intake system to the exhaust manifold via the EGR valve in response to the trigger signal; issue a fourth command to a turbo shaft actuator to rotate a turbine of a turbocharger responsive to the trigger signal, wherein rotation of the turbine occurs prior to the engine having any cylinder firing events; and issue a fifth command to the catalyst heater to turn on the catalyst heater responsive to the trigger signal, the catalyst heater being disposed between the turbine and a first catalyst brick, wherein: the rotation of the turbine causes the air to flow in a recirculation flow path as recirculated air; the first catalyst brick is disposed outside the recirculation flow path; the recirculation flow path comprises the exhaust manifold, exhaust walls between the exhaust manifold and the turbine, a turbine housing of the turbine, exhaust walls between the turbine and the wastegate, exhaust walls between the wastegate and the exhaust manifold, and exhaust walls between the turbine and the catalyst heater; the recirculated air is heated by the catalyst heater; and heat is transferred from the heated recirculated air to the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the wastegate, the exhaust walls between the wastegate and the exhaust manifold, and the exhaust walls between the turbine and the catalyst heater prior to turning on the engine; the recirculation flow path comprises the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the catalyst heater, exhaust walls between the catalyst heater and the first catalyst brick, exhaust walls between a second catalyst brick and the wastegate, and the exhaust walls between the wastegate and the exhaust manifold; the second catalyst brick is disposed inside the recirculation flow path; and heat is transferred from the heated recirculated air to the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the catalyst heater, the exhaust walls between the catalyst heater and the second catalyst brick, the exhaust walls between the second catalyst brick and the wastegate, the exhaust walls between the wastegate and the exhaust manifold, and the first second catalyst brick. ### Claim 8 (depends on 7) The system of claim 7, wherein the at least one memory further comprises instructions that upon execution by the at least one processor, causes the at least one processor to issue a seventh control signal sixth command to a compressor bypass valve actuator to open a compressor bypass valve responsive to the trigger signal. ### Claim 9 (depends on 7) The system of claim 7, wherein: the recirculation flow path is adjacent a first side of the first catalyst brick; and heat is transferred from the heated recirculated air to the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the catalyst heater, the exhaust walls between the catalyst heater and the wastegate, the exhaust walls between the wastegate and the exhaust manifold, the exhaust walls between the catalyst heater and the first catalyst brick, and the first catalyst brick via the first side of the first catalyst brick. ### Claim 10 A vehicle including a cold start emissions mitigation system comprising: at least one processor; and at least one memory communicatively coupled to the at least one processor, the at least one memory comprising instructions that upon execution by the at least one processor, causes the at least one processor to: issue a first command to a variable valve timing (VVT) system to at least partially open intake valves and exhaust valves of a plurality of cylinders of an engine during a previous shut down routine of the engine to enable air to flow from an intake system through the plurality of cylinders to an exhaust manifold; receive a trigger signal from a trigger signal source of the vehicle, wherein an ignition system turns on the vehicle and does not start the engine in response to the trigger signal; issue a second command to a wastegate actuator to open a wastegate responsive to the trigger signal; issue a third command to an exhaust gas recirculation (EGR) valve actuator to open an EGR valve to enable the air to flow from the intake system to the exhaust manifold via the EGR valve in response to the trigger signal; issue a fourth command to a turbo shaft actuator to rotate a turbine of a turbocharger responsive to the trigger signal, wherein rotation of the turbine occurs prior to the engine having any cylinder firing events; and issue a fifth command to the catalyst heater to turn on the catalyst heater responsive to the trigger signal, the catalyst heater being disposed between the turbine and a first catalyst brick, wherein: the rotation of the turbine causes the air to flow in a recirculation flow path as recirculated air; the first catalyst brick is disposed outside the recirculation flow path; the recirculation flow path comprises the exhaust manifold, exhaust walls between the exhaust manifold and the turbine, a turbine housing of the turbine, exhaust walls between the turbine and the wastegate, exhaust walls between the wastegate and the exhaust manifold, and exhaust walls between the turbine and the catalyst heater; the recirculated air is heated by the catalyst heater; and heat is transferred from the heated recirculated air to the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the wastegate, the exhaust walls between the wastegate and the exhaust manifold, and the exhaust walls between the turbine and the catalyst heater prior to turning on the engine: The recirculation flow path comprises the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the catalyst heater, exhaust walls between the catalyst heater and the first catalyst brick, exhaust walls between the second catalyst brick and the wastegate, and the exhaust walls between the wastegate and the exhaust manifold; the second catalyst brick is disposed inside the recirculation flow path; and heat is transferred from the heated recirculated air to the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the catalyst heater, the exhaust walls between the catalyst heater and the second catalyst brick, the exhaust walls between the second catalyst brick and the wastegate, the exhaust walls between the wastegate and the exhaust manifold, and the second catalyst brick. ### Claim 11 (depends on 10) The vehicle of claim 10, wherein the at least one memory further comprises instructions that upon execution by the at least one processor, causes the at least one processor to issue a sixth command to a compressor bypass valve actuator to open a compressor bypass valve responsive to the trigger signal. ### Claim 12 (depends on 10) The vehicle of claim 10, wherein: the recirculation flow path is adjacent a first side of the first catalyst brick; and heat is transferred from the heated recirculated air to the exhaust manifold, the exhaust walls between the exhaust manifold and the turbine, the turbine housing of the turbine, the exhaust walls between the turbine and the catalyst heater, the exhaust walls between the catalyst heater and the wastegate, the exhaust walls between the wastegate and the exhaust manifold, the exhaust walls between the catalyst heater and the first catalyst brick, and the first catalyst brick via the first side of the first catalyst brick. ### Claim 13 (depends on 10) The vehicle of claim 10, wherein the at least one memory further comprises instructions that upon execution by the at least one processor, causes the at least one processor to issue the second command to the wastegate actuator to fully open the wastegate. ### Claim 14 (depends on 10) The vehicle of claim 10, wherein the first catalyst brick comprises an oxidation catalyst. ### Claim 15 (depends on 10) The vehicle of claim 10, wherein the turbo shaft actuator is a motor generator unit (MGU). ### Claim 16 (depends on 7) The system of claim 7, wherein the first catalyst brick comprises an oxidation catalyst. ### Claim 17 (depends on 7) The system of claim 7, wherein the turbo shaft actuator is a motor generator unit (MGU).