# US 10,767,581 B2 · Method for operating an internal combustion engine for a motor vehicle, and a system for an internal combustion engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,767,581 B2 - Document ID: US10767581B2 - Status: Granted - Kind: B2 - Application number: 15/939,840 - Filed: 2018-03-29 - Published: 2018-08-09 - Granted: 2020-09-08 - Earliest claimed: 2015-10-02 - Assignees: Vitesco Technologies GmbH - Applicants: Continental Automotive GmbH - Inventors: Hong Zhang - Web page: https://patentgrep.com/patent/US10767581B2 ## CPC - F02D 41/0052: {Feedback control of engine parameters, e.g. for control of air/fuel ratio or intake air amount} - F02D 35/023: {by determining the cylinder pressure} - F02D 35/027: {using knock sensors} - F02D 41/0072: {Estimating, calculating or determining the EGR rate, amount or flow (sensors in EGR systems F02M26/45)} - F02D 41/2441: {characterised by the learning conditions} - F02P 5/045: {combined with electronic control of other engine functions, e.g. fuel injection (in general F02D37/02)} - F02P 5/1516: {with means relating to exhaust gas recirculation, e.g. turbo} - F02D 35/028: {by determining the combustion timing or phasing} - F02D 41/18: by measuring intake air flow - F02D 41/2429: {Methods of calibrating or learning} - F02D 2041/286: {comprising means for signal processing} - Y02T 10/40: Engine management systems - 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) - F02P: IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES ({anti-pollution means for internal-combustion engines F02B17/00}; specially adapted for rotary-piston or oscillating-piston engines F02B53/12; {ignition of gas turbine plants F02C7/26; ignition of jet propulsion plants F02K9/95; starting of combustion engines F02N9/00}; ignition of combustion apparatus in general, glowing plugs F23Q; measuring of physical variables in general G01; controlling in general G05; data processing in general G06; electrical components in general see Section H; {ignition coils H01F38/12}; sparking plugs H01T13/00) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A method for operating an internal combustion engine for a motor vehicle including receiving measurement signals of a cylinder pressure sensor and determining cylinder pressure fluctuations as a function of the received measurement signals of the cylinder pressure sensor. The method also includes increasing an exhaust gas recirculation rate of the internal combustion engine as a function of the determined cylinder pressure fluctuations until a predefined limiting value of the cylinder pressure fluctuations is reached. In addition, the method includes determining an actual value of the exhaust gas recirculation rate if the predefined limiting value of the cylinder pressure fluctuations is reached, and storing the determined actual value as a setpoint value for the exhaust gas recirculation rate of the internal combustion engine. ## Claims ### Claim 1 A method for operating an internal combustion engine for a motor vehicle, comprising: receiving measurement signals of a cylinder pressure sensor which are representative of a pressure in a cylinder of the internal combustion engine, determining cylinder pressure fluctuations in the cylinder of the internal combustion engine as a function of the received measurement signals of the cylinder pressure sensor, increasing an exhaust gas recirculation rate of the internal combustion engine as a function of the determined cylinder pressure fluctuations until a predefined limiting value of the cylinder pressure fluctuations is reached, determining an actual value of the exhaust gas recirculation rate if the predefined limiting value of the cylinder pressure fluctuations is reached, and storing the determined actual value as a setpoint value for the exhaust gas recirculation rate of the internal combustion engine, determining a center of combustion as a function of the received measurement signals of the cylinder pressure sensor, and adapting the setpoint value of the exhaust gas recirculation rate as a function of the determined center of combustion. ### Claim 2 (depends on 1) The method as claimed in claim 1, further comprising: receiving measurement signals of the cylinder pressure sensor which are representative of an intake pressure in an intake manifold of the internal combustion engine, determining an air mass, sucked in in the intake manifold, as a function of the received measurement signals of the cylinder pressure sensor that are representative of the intake pressure in the intake manifold, and controlling the exhaust gas recirculation rate of the internal combustion engine as a function of the determined air mass. ### Claim 3 (depends on 2) The method as claimed in claim 2, further comprising: determining a knocking intensity as a function of the received measurement signals of the cylinder pressure sensor or as a function of measurement signals of a knocking sensor, adapting an ignition angle of a crankshaft of the internal combustion engine which is coupled to a piston in the cylinder, as a function of the determined knocking intensity, and adapting the setpoint value of the exhaust gas recirculation rate as a function of the adaptation of the ignition angle. ### Claim 4 (depends on 1) The method as claimed in claim 1, further comprising: determining a combustion period as a function of the received measurement signals of the cylinder pressure sensor, and adapting the setpoint value of the exhaust gas recirculation rate as a function of the determined combustion period. ### Claim 5 (depends on 1) The method as claimed in claim 1, further comprising adapting the setpoint value of the exhaust gas recirculation rate by controlling an ignition angle of a crankshaft of the internal combustion engine which is coupled to a piston in the cylinder. ### Claim 6 (depends on 1) The method as claimed in claim 1, further comprising: receiving measurement signals of a knocking sensor which are representative of a knocking intensity of a respective cylinder, and adapting the setpoint value of the exhaust gas recirculation rate as a function of the received measurement signals of the knocking sensor. ### Claim 7 (depends on 1) The method as claimed in claim 1, further comprising: determining a knocking intensity as a function of the received measurement signals of the cylinder pressure sensor or as a function of measurement signals of a knocking sensor, adapting an ignition angle of a crankshaft of the internal combustion engine which is coupled to a piston in the cylinder, as a function of the determined knocking intensity, and adapting the setpoint value of the exhaust gas recirculation rate as a function of the adaptation of the ignition angle. ### Claim 8 (depends on 1) The method of claim 1, wherein increasing the exhaust gas recirculation rate of the internal combustion engine comprises increasing the exhaust gas recirculation rate until the center of combustion occurs. ### Claim 9 A system for an internal combustion engine having a cylinder, comprising: a cylinder pressure sensor which is arranged in the internal combustion engine of the motor vehicle and whose measurement signals are representative of a pressure in the cylinder of the internal combustion engine; and a device and memory coupled thereto, the device being configured to: receive measurement signals of the cylinder pressure sensor which are representative of a pressure in a cylinder of the internal combustion engine, determining cylinder pressure fluctuations in the cylinder of the internal combustion engine as a function of the received measurement signals of the cylinder pressure sensor, increasing an exhaust gas recirculation rate of the internal combustion engine as a function of the determined cylinder pressure fluctuations until a predefined limiting value of the cylinder pressure fluctuations is reached, determining an actual value of the exhaust gas recirculation rate if the predefined limiting value of the cylinder pressure fluctuations is reached, and storing the determined actual value in the memory as a setpoint value for the exhaust gas recirculation rate of the internal combustion engine, determine a center of combustion as a function of the received measurement signals of the cylinder pressure sensor, and adapt the setpoint value of the exhaust gas recirculation rate as a function of the determined center of combustion. ### Claim 10 (depends on 9) The system as claimed in claim 9, wherein the device is further configured to: receive measurement signals of the cylinder pressure sensor which are representative of an intake pressure in an intake manifold of the internal combustion engine, determine an air mass, sucked in in the intake manifold, as a function of the received measurement signals of the cylinder pressure sensor that are representative of the intake pressure in the intake manifold, and control the exhaust gas recirculation rate of the internal combustion engine as a function of the determined air mass. ### Claim 11 (depends on 9) The system as claimed in claim 9, wherein the device is further configured to determine a knocking intensity as a function of the received measurement signals of the cylinder pressure sensor or as a function of measurement signals of a knocking sensor, adapt an ignition angle of a crankshaft of the internal combustion engine which is coupled to a piston in the cylinder, as a function of the determined knocking intensity, and adapt the setpoint value of the exhaust gas recirculation rate as a function of the adaptation of the ignition angle. ### Claim 12 (depends on 9) The system as claimed in claim 9, wherein the device is further configured to determine a combustion period as a function of the received measurement signals of the cylinder pressure sensor, and adapt the setpoint value of the exhaust gas recirculation rate as a function of the determined combustion period. ### Claim 13 (depends on 9) The system as claimed in claim 9, wherein the device is further configured to adapt the setpoint value of the exhaust gas recirculation rate by controlling an ignition angle of a crankshaft of the internal combustion engine which is coupled to a piston in the cylinder. ### Claim 14 (depends on 9) The system as claimed in claim 9, wherein the device is further configured to receive measurement signals of a knocking sensor which are representative of a knocking intensity of a respective cylinder, and adapt the setpoint value of the exhaust gas recirculation rate as a function of the received measurement signals of the knocking sensor.