# US 8,571,784 B2 · Method for controlling a fuel injector of a diesel engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,571,784 B2 - Document ID: US8571784B2 - Status: Granted - Kind: B2 - Application number: 12/085,970 - Filed: 2006-10-19 - Published: 2010-02-18 - Granted: 2013-10-29 - Earliest claimed: 2005-12-02 - Assignees: Robert Bosch GmbH - Applicants: Stefan Polach; Dara Torkzadeh - Inventors: Stefan Polach; Dara Torkzadeh - Web page: https://patentgrep.com/patent/US8571784B2 ## CPC - F02D 41/401: {Controlling injection timing (F02D41/402 takes precedence)} - F02D 35/025: {by determining temperatures inside the cylinder, e.g. combustion temperatures} - F02D 35/028: {by determining the combustion timing or phasing} - F02B 3/06: with compression ignition (compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02) - F02D 41/0072: {Estimating, calculating or determining the EGR rate, amount or flow (sensors in EGR systems F02M26/45)} - F02D 41/3035: {a mode being the premixed charge compression-ignition mode} - F02D 2041/141: {using a feed-forward control element} - F02D 2041/1433: {using a model or simulation of the system} - 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) - F02B: INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL (gas-turbine plants F02C; hot-gas or combustion-product positive-displacement engine plants F02G) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A method for controlling a fuel injector of a diesel engine having a predefined control time from a control start, in which a setpoint value of a combustion start of a combustion chamber charge of the diesel engine is ascertained. The method is characterized in that an ignition delay between the control start and the combustion start is estimated from performance parameters of the diesel engine using a computing model, and the control start is formed on the basis of the setpoint value of the combustion start and the estimated ignition delay. A control unit controls the sequence of the method. ## Claims ### Claim 1 A method for controlling a fuel injector of a diesel engine having a predefined control time from a control start, the method comprising: determining a setpoint value for a combustion start of a combustion chamber charge of the diesel engine as a function of at least one of a rotational speed and a torque request defined by a driver intent, and an operating mode; estimating an ignition delay between the control start and the combustion start from performance parameters of the diesel engine using a computing model; and forming the control start based on the setpoint value of the combustion start and the estimated ignition delay. ### Claim 2 (depends on 1) The method of claim 1, wherein actual values of the combustion start are determined and adjusted to setpoint values in a closed loop. ### Claim 3 (depends on 2) The method of claim 2, wherein the ignition delay is estimated using a computing model, which simulates combined effects of at least two performance parameters of the diesel engine. ### Claim 4 (depends on 3) The method of claim 3, wherein one of the at least two performance parameters includes an exhaust gas recirculation rate. ### Claim 5 (depends on 4) The method of claim 4, wherein the at least two performance parameters include at least one of a combustion chamber charge and a temperature of the combustion chamber charge. ### Claim 6 (depends on 4) The method of claim 4, wherein an inert gas content in a combustion chamber charge resulting from the exhaust gas recirculation is considered in estimating an effect of the combustion chamber charge on the ignition delay. ### Claim 7 (depends on 4) The method of claim 4, wherein a temperature increase of the combustion chamber charge resulting from the exhaust gas recirculation rate is considered in estimating an influence of the temperature of the combustion chamber charge. ### Claim 8 (depends on 4) The method of claim 4, wherein the at least two performance parameters include at least one of a combustion chamber charge and a temperature of the combustion chamber charge, and wherein an inert gas content in a combustion chamber charge resulting from the exhaust gas recirculation is considered in estimating an effect of the combustion chamber charge on the ignition delay. ### Claim 9 (depends on 8) The method of claim 8, wherein a temperature increase of the combustion chamber charge resulting from the exhaust gas recirculation rate is considered in estimating an influence of the temperature of the combustion chamber charge. ### Claim 10 A control unit to control a fuel injector of a diesel engine having a predefined control time from a control start, comprising: a determining arrangement to determine a setpoint value of a combustion start of a combustion chamber charge of the diesel engine as a function of at least one of a rotational speed and a torque request define by a driver intent, and an operating mode; and another determining arrangement to estimate an ignition delay between the control start and the combustion start from performance parameters of the diesel engine, and to form the control start from the setpoint value of the combustion start and the estimated ignition delay. ### Claim 11 (depends on 10) The control unit of claim 10, wherein actual values of the combustion start are determined and adjusted to setpoint values in a closed loop. ### Claim 12 (depends on 11) The control unit of claim 11, wherein the ignition delay is estimated using a computing model, which simulates combined effects of at least two performance parameters of the diesel engine. ### Claim 13 (depends on 12) The control unit of claim 12, wherein one of the at least two performance parameters includes an exhaust gas recirculation rate. ### Claim 14 (depends on 13) The control unit of claim 13, wherein the at least two performance parameters include at least one of a combustion chamber charge and a temperature of the combustion chamber charge. ### Claim 15 (depends on 13) The control unit of claim 13, wherein an inert gas content in a combustion chamber charge resulting from the exhaust gas recirculation is considered in estimating an effect of the combustion chamber charge on the ignition delay. ### Claim 16 (depends on 13) The control unit of claim 13, wherein a temperature increase of the combustion chamber charge resulting from the exhaust gas recirculation rate is considered in estimating an influence of the temperature of the combustion chamber charge. ### Claim 17 (depends on 13) The control unit of claim 13, wherein the at least two performance parameters include at least one of a combustion chamber charge and a temperature of the combustion chamber charge, and wherein an inert gas content in a combustion chamber charge resulting from the exhaust gas recirculation is considered in estimating an effect of the combustion chamber charge on the ignition delay. ### Claim 18 (depends on 17) The control unit of claim 17, wherein a temperature increase of the combustion chamber charge resulting from the exhaust gas recirculation rate is considered in estimating an influence of the temperature of the combustion chamber charge.