Ignition system and method for operating an ignition system

Patent metadata

Field	Value
Publication number	US-2016281673-A1
Application number	US-201415036040-A
Country	US
Kind code	A1
Filing date	Oct 16, 2014
Priority date	Nov 14, 2013
Publication date	Sep 29, 2016
Grant date	—

Abstract

A method is described for operating an ignition system for an internal combustion engine, including a primary voltage generator and a boost converter for maintaining a spark generated with the aid of the primary voltage generator. An ascertainment of a modified energy requirement for an ignition spark to be maintained with the aid of the boost converter is followed by a modification of a switch-on time of the boost converter relative to a switch-off time of the primary voltage generator.

First claim

1 - 17 . (canceled)

18 . A method for operating an ignition system for an internal combustion engine, the ignition system including a primary voltage generator and a boost converter for maintaining an ignition spark generated with the aid of the primary voltage generator, the method comprising:
ascertaining a modified energy requirement for an ignition spark to be maintained with the aid of the boost converter; and modifying, based on the ascertained modified energy requirement, a switch-on time of the boost converter one of: i) relative to a switch-off time of the primary voltage generator, or ii) relative to a crank shaft angle of an internal combustion engine provided with the ignition system.

19 . The method as recited in claim 18 , wherein the ascertaining of the modified energy requirement includes measuring at least one of: i) an ignition spark current, ii) an ignition spark voltage, and iii) a voltage corresponding to the ignition spark voltage.

20 . The method as recited in claim 18 , wherein the ascertaining of the modified energy requirement includes ascertaining an operating state by receiving a signal from an electronic control unit.

21 . The method as recited in claim 20 , wherein the electronic control unit is an engine control unit.

22 . The method as recited in claim 20 , wherein at least one of:
the modification of the switch-on time includes a read-out of a switch-on time assigned to the ascertained operating state, and the modification of the switch-on time includes a classification of the operating state and an application of a switch-on time assigned to the ascertained class.

23 . The method as recited in claim 18 , wherein the ascertaining of the modified energy requirement includes comparing a measured electrical parameter of an ignition spark or a signal generated by an electronic control unit with an assigned reference.

24 . The method as recited in claim 23 , further comprising:
classifying the result of the comparison; and modifying a switch-on time of the boost converter as a function of a parameter assigned to the class.

25 . The method as recited in claim 22 , wherein the modification of the switch-on time in response to a reduced energy requirement results in a switching on of the boost converter at least one of: i) at a later point in time, and ii) in response to an increased energy requirement, in an earlier switching on of the boost converter.

26 . The method as recited in claim 23 , wherein:
the ascertainment of a modified energy requirement takes place in the course of a first ignition process, and the modification of the switch-on time takes place in the course of a second, subsequent ignition process.

27 . The method as recited in claim 18 , wherein the switch-on time is modified at least one of: i) as a function of the ascertained operating state, and ii) as a function of the ascertained energy requirement.

28 . The method as recited in claim 18 , wherein the switch-on time is predefined in a first ignition process as a function of an operating state and determined as a function of the ascertained energy requirement for following ignition processes.

29 . The method as recited in claim 18 , wherein the ascertaining of the modified energy requirement includes:
ascertaining at least one of: i) an electrical parameter, ii) a change of the parameter, and iii) a change speed of the parameter, the electrical parameter being at least one of: i) a current of the ignition spark, and ii) a voltage characterizing a voltage of the ignition spark; and ascertaining whether at least one of: i) an exceedance condition, and ii) undercut condition, is met by ascertaining whether a comparison variable at least one of: i) exceeds a predetermined upper threshold value, and ii) undercuts a predetermined lower threshold value, the comparison variable being at least one of: i) the ascertained parameter, ii) the change of the ascertained parameter, and iii) the change speed of the ascertained parameter.

30 . The method as recited in claim 29 , wherein the modification of the switch-on time includes:
modifying the switch-on time to a later point in time relative to the switch-off time of the primary voltage generator if the exceedance condition is met; or modifying the switch-on time to an earlier point in time relative to the switch-off time of the primary voltage generator if the undercut condition is met.

31 . The method as recited in claim 30 , wherein the modification of the switch-on time takes place in predefinable steps or continuously.

32 . The method as recited in claim 17 , wherein the boost converter is switched on with the aid of a switch.

33 . A machine-readable memory medium storing a computer program for operating an ignition system for an internal combustion engine, the ignition system including a primary voltage generator and a boost converter for maintaining an ignition spark generated with the aid of the primary voltage generator, the computer program, when executed by a control unit, causing the control unit to perform:
ascertaining a modified energy requirement for an ignition spark to be maintained with the aid of the boost converter; and modifying, based on the ascertained modified energy requirement, a switch-on time of the boost converter one of: i) relative to a switch-off time of the primary voltage generator, or ii) relative to a crank shaft angle of an internal combustion engine provided with the ignition system.

34 . An ignition system for an internal combustion engine, the ignition system including a primary voltage generator and a boost converter for maintaining an ignition spark generated with the aid of the primary voltage generator, the ignition system configured to:
ascertain a modified energy requirement for an ignition spark to be maintained with the aid of the boost converter; and modify, based on the ascertained modified energy requirement, a switch-on time of the boost converter one of: i) relative to a switch-off time of the primary voltage generator, or ii) relative to a crank shaft angle of an internal combustion engine provided with the ignition system.

Assignees

• Bosch Gmbh Robert

Inventors

• Skowronek Tim
• Pawlak Thomas
• Sinz Wolfgang

Classifications

• F02P9/002

  Control of spark intensity, intensifying, lengthening, suppression (by means of current control in the storage devices F02P3/05, F02P3/09, during starting F02P15/12) · CPC title

• F02P5/1502 Primary

  using one central computing unit · CPC title

• F02P17/12

  Testing characteristics of the spark, ignition voltage or current (testing of sparking plugs H01T13/60) · CPC title

• Y02T10/40

  Engine management systems · CPC title

• F02P3/0407

  Opening or closing the primary coil circuit with electronic switching means (F02P3/045 - F02P3/055 take precedence) · CPC title