# US 8,783,226 B2 · Knocking control system for gas engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,783,226 B2 - Document ID: US8783226B2 - Status: Granted - Kind: B2 - Application number: 13/122,138 - Filed: 2009-09-17 - Published: 2011-10-27 - Granted: 2014-07-22 - Earliest claimed: 2008-10-01 - Assignees: Kawasaki Jukogyo Kabushiki Kaisha - Applicants: Tsukasa Imamura; Tomohiko Sugimoto; Tetsuo Tokuoka; Hiroyoshi Ishii - Inventors: Tsukasa Imamura; Tomohiko Sugimoto; Tetsuo Tokuoka; Hiroyoshi Ishii - Web page: https://patentgrep.com/patent/US8783226B2 ## CPC - F02B 19/108: {with fuel injection at least into pre-combustion chamber, i.e. injector mounted directly in the pre-combustion chamber} - F02B 19/12: with positive ignition (engines with non-timed positive ignition, and with incandescent chambers F02B9/08) - F02D 19/024: {by controlling fuel injectors} - F02M 21/0275: {for in-cylinder direct injection, e.g. injector combined with spark plug} - F02M 21/0278: {Port fuel injectors for single or multipoint injection into the air intake system} - F02M 21/0284: {Arrangement of multiple injectors or fuel-air mixers per combustion chamber} - F02P 5/152: dependent on pinking (detecting or indicating knocks in internal-combustion engines G01L23/22) - G01L 23/225: {circuit arrangements therefor} - F02P 13/00: Sparking plugs structurally combined with other parts of internal-combustion engines ({connection of ignition coil to spark plug connector F02P3/02;} with fuel injectors F02M57/06 {; spark plug connector per se H01T13/04 – H01T13/06; predominant aspects of sparking plug, see H01T13/40 – H01T13/44}) - Y02T 10/12: Improving ICE efficiencies - Y02T 10/30: Use of alternative fuels, e.g. biofuels - Y02T 10/40: Engine management systems - F02B: INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL (gas-turbine plants F02C; hot-gas or combustion-product positive-displacement engine plants F02G) - 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) - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF - 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) - G01L: MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE (weighing G01G) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A knocking control system for a gas engine of the present invention, being configured to calculate a knocking occurrence ratio (SEV) which is a ratio of a cycle number of cycles in which a predetermined knocking occurs for a period of the cycles of the predetermined cycle number, to the predetermined cycle number, decide a target value of an ignition timing of the ignition device based on a deviation (ΔSEV) between an occurrence ratio delay calculation value (SEVAVE) obtained by performing delay calculation of the knocking occurrence ratio and a predetermined occurrence ratio target value (SEVSET), and drive the ignition device so that the ignition timing reaches a command value (IGN) decided according to the target value. ## Claims ### Claim 1 A knocking control system for a gas engine comprising: an ignition device for igniting an air-fuel mixture supplied to the gas engine; a knocking detector for detecting a knocking in a cylinder of the gas engine; a phase angle detector for detecting a phase angle of the gas engine; and a controller for driving the ignition device, the controller being configured to calculate a knocking occurrence ratio defined as a value obtained by dividing a determined number of cycles in which knocking occurs within a predetermined number of cycles by the predetermined number of cycles, perform a delay calculation of the knocking occurrence ratio to calculate an occurrence ratio delay calculation value, calculate a deviation between the occurrence ratio delay calculation value and a predetermined occurrence ratio target value, and drive the ignition device so that the ignition timing reaches a command value decided according to a target value of the ignition timing of the ignition device, by retarding the target value of the ignition timing of the ignition device based on the deviation if the occurrence ratio delay calculation value is larger than the occurrence ratio target value, and by advancing the target value of the ignition timing of the ignition device based on the deviation if the occurrence ratio delay calculation value is smaller than the occurrence ratio target value. ### Claim 2 (depends on 1) The knocking control system for the gas engine according to claim 1, wherein the delay calculation is a moving average. ### Claim 3 (depends on 1) The knocking control system for the gas engine according to claim 1, wherein a retard angle amount of the ignition timing per unit period in a case where the ignition timing is retarded is larger than an advancement amount of the ignition timing per unit period in a case where the ignition timing is put advanced. ### Claim 4 (depends on 1) The knocking control system for the gas engine according to claim 1, wherein the controller is configured to calculate a reference value of the ignition timing by performing the delay calculation of a command value of the ignition timing of the ignition device and decide the target value of the ignition timing of the ignition device by adding to the reference value a compensation value decided based on a deviation between the occurrence ratio delay calculation value and the occurrence ratio target value. ### Claim 5 (depends on 4) The knocking control system for the gas engine according to claim 4, wherein the knocking detector detects knocking with an intensity at one of a plurality of levels; and the controller, when, during the passage of said predetermined number of cycles a determined number of cycles in which knocking with a predetermined intensity or higher has occurred exceeds a threshold, is configured to calculate a retard angle amount of the ignition timing of the ignition device, which is decided based on the determined number of cycles, and retard by the retard angle amount, the target value of the ignition timing decided based on the deviation between the occurrence ratio delay calculation value and the occurrence ratio target value. ### Claim 6 (depends on 1) The knocking control system for the gas engine according to claim 1, wherein the gas engine includes a main combustion chamber and a sub-combustion chamber which are supplied with the air-fuel mixture; and the ignition device includes an ignition plug for sparking and igniting the air-fuel mixture supplied to the sub-combustion chamber.