# US 10,371,116 B2 · Method and apparatus for controlling a multi-cylinder 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 10,371,116 B2 - Document ID: US10371116B2 - Status: Granted - Kind: B2 - Application number: 15/836,183 - Filed: 2017-12-08 - Published: 2019-06-13 - Granted: 2019-08-06 - Earliest claimed: 2017-12-08 - Assignees: GM Global Technology Operations LLC - Applicants: GM Global Technology Operations LLC - Inventors: Junfeng Zhao; Jun-mo Kang - Web page: https://patentgrep.com/patent/US10371116B2 ## CPC - F02P 5/153: dependent on combustion pressure - F02D 35/023: {by determining the cylinder pressure} - F02D 41/008: {Controlling each cylinder individually} - F02D 41/1497: {With detection of the mechanical response of the engine} - F02P 5/045: {combined with electronic control of other engine functions, e.g. fuel injection (in general F02D37/02)} - F02P 5/1512: {with particular means concerning an individual cylinder} - F02D 2200/101: Engine speed - Y02T 10/40: Engine management systems - 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) - 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 multi-cylinder spark-ignition internal combustion engine includes a monitored cylinder and a plurality of non-monitored cylinders, a pressure sensor disposed to monitor in-cylinder pressure in the monitored cylinder and a rotational position sensor. The controller is in communication with the pressure sensor, the rotational position sensor and the spark controller. The controller monitors, via the pressure sensor, in-cylinder pressure for the monitored cylinder during a combustion event, and determines a first spark timing based upon a desired spark timing and the in-cylinder pressure. A spark controller controls spark timing for the monitored cylinder based upon the final spark timing. The controller monitors, via the rotational position sensor, engine rotational speed and crankshaft speed pulsations associated with the monitored cylinder and the non-monitored cylinders, and determines a modal coefficient for the non-monitored cylinders based upon the engine rotational speed and the crankshaft speed pulsations. ## Claims ### Claim 1 A method for controlling a multi-cylinder spark-ignition internal combustion engine that includes a monitored cylinder and a plurality of non-monitored cylinders, wherein an in-cylinder pressure sensor is disposed in the monitored cylinder, the method comprising: monitoring, via the pressure sensor, in-cylinder pressure for the monitored cylinder during a combustion event for the monitored cylinder; determining a first spark timing for the monitored cylinder based upon a desired spark timing and the in-cylinder pressure; controlling spark timing for the monitored cylinder based upon the first spark timing; monitoring, via a rotational position sensor, engine rotational speed and crankshaft speed pulsations associated with the monitored cylinder and the non-monitored cylinders; determining a modal coefficient for the non-monitored cylinders based upon the engine rotational speed and the crankshaft speed pulsations; determining coefficient errors for the non-monitored cylinders based upon the modal coefficients; executing a balance control to determine a spark timing adjustment for each of the non-monitored cylinders based upon the coefficient error; determining final spark timings for the non-monitored cylinders based upon the desired spark timing and the respective spark timing adjustment; and controlling spark timing for each of the non-monitored cylinders based upon the respective final spark timing. ### Claim 2 (depends on 1) The method of claim 1, comprising executing a principal component analysis to determine the modal coefficient for the non-monitored cylinders based upon the engine rotational speed and the crankshaft speed pulsations. ### Claim 3 (depends on 1) The method of claim 1, further comprising determining a combustion parameter for the combustion event for the monitored cylinder based upon the in-cylinder pressure. ### Claim 4 (depends on 3) The method of claim 3, wherein determining the first spark timing for the monitored cylinder based upon the desired spark timing and the in-cylinder pressure comprises: determining a first error term based upon the combustion parameter and a desired state for the combustion parameter; determining a control point for the combustion parameter based upon the first error term; determining the desired spark timing for the monitored cylinder based upon an engine operating point; and determining the first spark timing for the monitored cylinder based upon the desired spark timing and the control point for the combustion parameter. ### Claim 5 (depends on 3) The method of claim 3, wherein determining the combustion parameter for the combustion event for the monitored cylinder comprises determining a crank angle associated with a parameter associated with a mass-burn-fraction point for a cylinder charge. ### Claim 6 (depends on 5) The method of claim 5, wherein the parameter associated with the mass-burn-fraction point for the cylinder charge comprises a crank angle associated with a 50% mass-burn-fraction point for the cylinder charge. ### Claim 7 A method for controlling a multi-cylinder spark-ignition internal combustion engine that includes a monitored cylinder and a plurality of non-monitored cylinders, wherein a pressure sensor is disposed to monitor in-cylinder pressure in the monitored cylinder, the method comprising: monitoring, via the pressure sensor, in-cylinder pressure for the monitored cylinder during a combustion event for the monitored cylinder; determining a first spark timing for the monitored cylinder based upon a desired spark timing and the in-cylinder pressure; controlling spark timing for the monitored cylinder based upon the first spark timing; monitoring, via a rotational position sensor, engine rotational speed and crankshaft speed pulsations associated with the monitored cylinder and the non-monitored cylinders; determining modal coefficients for the non-monitored cylinders based upon the engine rotational speed and the crankshaft speed pulsations; determining coefficient errors for the non-monitored cylinders based upon the modal coefficients; executing a balance control to determine a spark timing adjustment for each of the non-monitored cylinders based upon the respective coefficient error; determining a final spark timing for each of the non-monitored cylinders based upon the desired spark timing and the respective spark timing adjustment; and controlling spark timing for each of the non-monitored cylinders based upon the respective final spark timing. ### Claim 8 (depends on 7) The method of claim 7, comprising executing a principal component analysis to determine the modal coefficients for the non-monitored cylinders based upon the engine rotational speed and the crankshaft speed pulsations. ### Claim 9 (depends on 7) The method of claim 7, wherein determining the final spark timing for the monitored cylinder based upon the desired spark timing and the in-cylinder pressure comprises: determining a combustion parameter for the combustion event for the monitored cylinder based upon the in-cylinder pressure; determining a first error term based upon the combustion parameter and a desired state for the combustion parameter; determining a control point for the combustion parameter based upon the first error term; determining the desired spark timing for the monitored cylinder based upon an engine operating point; and determining the final spark timing for the monitored cylinder based upon the desired spark timing and the control point for the combustion parameter. ### Claim 10 (depends on 7) The method of claim 7, wherein determining a combustion parameter comprises determining a crank angle associated with a parameter associated with a mass-burn-fraction point for the cylinder charge. ### Claim 11 (depends on 10) The method of claim 10, wherein the parameter associated with the mass-burn-fraction point for the cylinder charge comprises a crank angle associated with a 50% mass-burn-fraction point for the cylinder charge. ### Claim 12 A multi-cylinder spark-ignition internal combustion engine, comprising a monitored cylinder and a plurality of non-monitored cylinders; a plurality of pistons disposed in the monitored cylinder and the non-monitored cylinders, the pistons coupled to a crankshaft; a pressure sensor disposed to monitor in-cylinder pressure in the monitored cylinder; a rotational position sensor disposed to monitor rotational position of the crankshaft; a spark ignition system including a spark controller in communication with a plurality of spark igniters that are disposed in the monitored cylinder and the plurality of non-monitored cylinders; a controller, in communication with the pressure sensor, the rotational position sensor and the spark controller, the controller including an instruction set executable to: monitor, via the pressure sensor, in-cylinder pressure for the monitored cylinder during a combustion event for the monitored cylinder; determine a first spark timing for the monitored cylinder based upon a desired spark timing and the in-cylinder pressure; control, via the spark controller, spark timing for the monitored cylinder based upon the first spark timing; monitor, via the rotational position sensor, engine rotational speed and crankshaft speed pulsations associated with the monitored cylinder and the non-monitored cylinders; determine a modal coefficient for the non-monitored cylinders based upon the engine rotational speed and the crankshaft speed pulsations; determine coefficient errors for the non-monitored cylinders based upon the modal coefficients; execute a balance control to determine a spark timing adjustment for each of the non-monitored cylinders based upon the coefficient error; determine final spark timings for the non-monitored cylinders based upon the desired spark timing and the respective spark timing adjustment; and control, via the spark controller, spark timing for each of the non-monitored cylinders based upon the respective final spark timing. ### Claim 13 (depends on 12) The engine of claim 12, wherein the instruction set executes a principal component analysis to determine the modal coefficient for the non-monitored cylinders based upon the engine rotational speed and the crankshaft speed pulsations. ### Claim 14 (depends on 12) The engine of claim 12, wherein the instruction set is executable to determine a combustion parameter for the combustion event for the monitored cylinder based upon the in-cylinder pressure. ### Claim 15 (depends on 12) The engine of claim 12, wherein the instruction set executable to determine the first spark timing for the monitored cylinder based upon the desired spark timing and the in-cylinder pressure comprises the instruction set executable to: determine a combustion parameter for the combustion event for the monitored cylinder based upon the in-cylinder pressure; determine a first error term based upon the combustion parameter and a desired state for the combustion parameter; determine a control point for the combustion parameter based upon the first error term; determine the desired spark timing for the monitored cylinder based upon an engine operating point; and determine the first spark timing for the monitored cylinder based upon the desired spark timing and the control point for the combustion parameter. ### Claim 16 (depends on 12) The engine of claim 12, wherein the instruction set is executable to determine a crank angle associated with a parameter associated with a mass-burn-fraction point for a cylinder charge. ### Claim 17 (depends on 16) The engine of claim 16, wherein the parameter associated with the mass-burn-fraction point for the cylinder charge comprises a crank angle associated with a 50% mass-burn-fraction point for the cylinder charge.