Method and system for detecting component replacement in an ignition system of a spark-ignition engine

Abstract

The invention relates to a method for detecting replacement of a component of an ignition system of a spark-ignition internal combustion engine. The method comprises the steps of determining at least one parameter indicative of the operation or condition of the ignition system; and detecting replacement of the component based on a comparison of the parameter with at least one reference value.

Description

Technical Field

[0001] The invention relates to a method for detecting replacement of a component of an ignition system in a spark-ignition internal combustion engine. Further, the invention relates to an ignition system of a spark-ignition internal combustion engine for carrying out such a method. Background Art

[0002] In a spark-ignition internal combustion engine, such as an Otto engine, the combustion of a fuel mixture filled in the engine cylinder is initiated by an ignition system equipped with a spark plug. In such a system, the spark plug is configured to deliver an electric current from a current source to a combustion chamber to ignite the filled fuel mixture in the combustion chamber by an electric spark. As a result, high-temperature and high-pressure gases begin to be generated in the combustion chamber, which exert a force on an associated piston in the cylinder and thus axially move the piston, which rotates the crankshaft of the engine. In this way, chemical energy is converted into mechanical energy.

[0003] In order to ensure stable operating conditions of the engine, correct and reliable operation of the ignition system must be ensured. However, ignition systems, i.e. their spark plugs, are usually subject to considerable wear, resulting in a limited service life. Therefore, in order to avoid unplanned downtimes and improve the availability and maintenance of the engine, methods are known for monitoring the operating or wear conditions of the ignition system and its components in order to avoid malfunctions or damage to the engine.

[0004] For example, EP 3 276 156 A1 discloses a method for detecting critical wear conditions of spark plugs associated with cylinders of a spark ignition engine by monitoring the current in the ignition system during engine operation. In this way, defective spark plugs in the ignition system can be detected before engine damage or failure occurs. Summary of the invention

[0005] Starting from the prior art, the object of the present invention is to provide a method and a system which contribute to improving the monitoring of the ignition system in order to avoid unplanned downtimes of the engine.

[0006] This object is solved by a method having the features described below and an ignition system for an internal combustion engine having the features described below.Preferred embodiments are also set forth in the present description and the drawings.

[0007] Therefore, a method for detecting replacement of a component of an ignition system of a spark-ignition internal combustion engine is provided. The method comprises the steps of determining at least one parameter indicative of the operation or condition of the ignition system; and detecting replacement of the component based on a comparison of the parameter with at least one reference value.

[0008] Furthermore, an ignition system for a spark-ignition internal combustion engine is provided. The ignition system comprises a control unit configured to determine at least one parameter indicative of operation or condition of the ignition system and to detect replacement of a component of the ignition system based on a comparison of the parameter with at least one reference value.

[0009] The control unit of the proposed ignition system can be provided for executing the above-mentioned method for detecting replacement of a component of the ignition system. Therefore, the technical features described in conjunction with the proposed method can also relate to and be applied to the proposed ignition system, and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings, in which:

[0011] Figure 1 An internal combustion engine equipped with an ignition system is schematically shown;

[0012] Figure 2 shows instructions for detecting Figure 1 A flowchart of a method for replacing a component of an ignition system as depicted in; and

[0013] Figures 3 to 6 Shows the description Figure 2 a flow chart of the sub-steps of the depicted method;

[0014] Figure 5 and 6 A diagram illustrating a method according to another embodiment of the present invention is shown. Figure 2 a flow chart of the sub-steps of the depicted method; and

[0015] Figure 7 shows the matrix stored in Figure 1 Table of data sets in a control unit of the depicted ignition system. DETAILED DESCRIPTION

[0016] Hereinafter, the present invention will be explained in more detail with reference to the accompanying drawings. In the accompanying drawings, the same elements are denoted by the same reference numerals, and repeated descriptions thereof may be omitted to avoid redundancy.

[0017] Figure 1 Schematically depicted is a spark-ignition internal combustion engine 10, also referred to hereinafter as an 'engine', provided in the form of a reciprocating engine, particularly a gas engine. However, it will be apparent to those skilled in the art that the engine may be any type of spark-ignition internal combustion engine, such as a dual fuel engine or any other Otto engine using a spark plug to ignite a fuel mixture within a combustion chamber of the engine.

[0018] Specifically, the engine 10 includes at least one cylinder 12, preferably more than one cylinder, such as four, six, eight or more cylinders 12. In other words, the engine 10 may be of any size, i.e., have any number of cylinders 12 and be in any configuration, such as a V-type or in-line engine.

[0019] Each cylinder 12 is provided with a combustion chamber 14 defined by the cylinder 12 and a piston 16 accommodated therein. The piston 16 is configured to reciprocate within the cylinder 12 and is connected to a crankshaft 18 of the engine 10 via a connecting rod 20.

[0020] During operation of engine 10, each combustion chamber 14 is supplied with a fuel mixture which is ignited therein to generate high temperature and pressure gases which apply a force to an associated piston 16 and thereby axially move the piston, thereby rotating crankshaft 18. In this way, chemical energy is converted into mechanical energy.

[0021] In order to supply the fuel mixture into the combustion chamber 14, the engine 10 is equipped with an intake passage 22 leading to the combustion chamber 14, wherein the supply of the fuel mixture into the combustion chamber 14 is variably adjusted by an intake valve 24. The intake passage 22 is configured to provide the fuel mixture by mixing intake air with a fuel medium, specifically natural gas, i.e., including hydrocarbon gas.

[0022] The combustion chamber 14 of each cylinder 12 is further connected to an exhaust passage 26 for exhausting combustion gases from the combustion chamber 14, ie after combustion of the fuel mixture has occurred. To control the exhaust of the combustion gases, an exhaust valve 28 is provided which variably exhausts the exhaust gases from the combustion chamber 14 into the exhaust passage 26.

[0023] Further, engine 10 is equipped with an ignition system 30 having at least one spark plug 32 , each associated with at least one of cylinders 12 .

[0024] The basic structure and function of such an internal combustion engine 10 and its components are well known to those skilled in the art and are therefore not further described. Instead, the features of the ignition system 30 of the engine 10 interconnected with the present invention are described below. Although not further described in the present invention, it will be understood by those skilled in the art that the internal combustion engine 10 may be equipped with further components, such as a fuel system, an air system, a cooling system, drive train components, etc.

[0025] The ignition system 30 is configured to ignite a fuel mixture supplied to the combustion chamber 14 by an electric spark generated by a spark plug 32 in the combustion chamber 14. To this end, the ignition system 30 includes at least one ignition coil 34, each ignition coil being associated with one cylinder 12. The ignition coil 34 is electrically connected to a control unit 36 ​​and one of the at least one spark plug 32. The control unit 36 ​​is configured to control the operation of the at least one spark plug 32 by selectively supplying current to the at least one ignition coil 34. In the illustrated configuration, the control unit 36 ​​is electrically connected to each of the at least one ignition coil 34 and thus forms a common control unit. Alternatively, the ignition system 30 may be provided with more than one control unit 36, each of which is associated with a different ignition coil 34 and thus with a different cylinder 12 of the engine 10.

[0026] The ignition coil 34 includes a primary winding 38 and a secondary winding 40 that are inductively coupled to each other. The primary winding 38 is electrically coupled to the control unit 36 ​​for receiving current from a current source (not shown), and the secondary winding 40 is electrically coupled to the spark plug 32.

[0027] More specifically, the control unit 36 ​​is configured to selectively supply current to the primary winding 38, thereby inducing a magnetic field in the secondary winding 40. This causes the voltage across the spark plug 32 to increase. When the current supply to the primary winding 38 is cut off, the voltage across the spark plug 32 increases, which may cause the spark plug 32 within the combustion chamber 14 to discharge, thereby causing the fuel mixture therein to ignite. Therefore, by selectively supplying current to the primary winding 38, the control unit 36 ​​is configured to control the desired ignition timing for igniting the fuel mixture within the combustion chamber 14.

[0028] The control unit 36 ​​is a general engine control module capable of controlling the internal combustion engine 10 and / or its associated components. The control unit 36 ​​may include all components required to run the application, such as memory, auxiliary storage devices and processors, such as a central processing unit or any other device known in the art for controlling the engine 10 and its components. Various other known circuits may be associated with the control unit 36, including current supply circuits, signal conditioning circuits, communication circuits, and other appropriate circuits. The control unit 36 ​​is configured to analyze and compare the received and stored data, and to determine whether an action is required based on instructions and data stored in the memory or input by the user. In the illustrated configuration, the control unit 36 ​​includes a memory unit 42, and is configured to compare the received value with the target value stored in the memory unit 42, and to send a signal to one or more components based on the result of the comparison to change its operating condition.

[0029] In the following, reference Figures 2 to 4A method is described for detecting replacement of a component of the ignition system 30. The method is executed by a control unit 36 ​​forming a general engine control module of the engine 10, but may also be executed by any other suitable control unit.

[0030] Figure 2 A flow chart illustrating a method for detecting replacement of a component of the ignition system 30 is shown. For simplicity, hereinafter, a method for detecting replacement of a component associated with one cylinder 12 of the engine 10 is described. The control unit 36 ​​is also configured to similarly detect replacement of components associated with other cylinders 12. However, to avoid redundancy, repeated description thereof is omitted.

[0031] The proposed method is configured to determine whether a component of the ignition system 30 has been replaced. Specifically, the illustrated method is configured to detect replacement of at least one of the spark plug 32 and the ignition coil 34 of the ignition system 30. Alternatively, the method may be configured to detect replacement of other components of the ignition system 30.

[0032] The method comprises a routine of subsequent steps S2 to S10 which are executed in response to an engine start, i.e. when an engine start command is received, such as Figure 2 In other words, each time the engine 10 is restarted, ie, when the engine 10 is started after being stopped, the routine or sequence of steps S2 to S10 is started.

[0033] When the engine is started, step S2 is executed, during which a plurality of parameters RR1 to RR4 are determined. To this end, in step S2, a measurement cycle C is executed. i During this period, a plurality of parameters are determined. Specifically, a plurality of parameters are determined for each cylinder 12 respectively.

[0034] Figure 3 The diagram illustrates the execution of the measurement cycle C in more detail by showing its sub-steps S2.1 to S.11. i Flow chart of step S2. In one measurement cycle C i During the execution of , a plurality of parameters indicative of the operation or condition of the ignition system 30, namely, four parameters RR1 to RR4, are determined. In general, the parameters RR1 to RR4 quantify characteristics of the engine 10 indicative of the operation or condition of the ignition system 30. In the context of the present invention, the term "indicative of the operation of the ignition system" may refer to parameters that quantify or specify an operating characteristic or condition of the ignition system 30, i.e., parameters associated with a specific operating condition of the ignition system 30. The term "indicative of the condition of the ignition system" may refer to parameters that quantify or specify a condition (e.g., a health condition, an aging condition, a wear condition, etc.) of the ignition system 30, which is specifically independent of the specific operating condition of the ignition system 30.

[0035] In the illustrated configuration, four parameters RR1 to RR4 relate to, i.e. quantify, the same characteristics of the ignition system 30, which are determined or measured during different operating conditions, as may be shown from steps S2.1, S2.2, S2.6 and S2.10. The parameters RR1 to RR4 are indicative of the current flowing through the ignition coil 34 of the ignition system 30 during spark plug actuation. Specifically, each of the parameters RR1 to RR4 is indicative of the current rise time duration in the primary winding 38 of the ignition coil 34, and may therefore also be referred to as a 'rise time parameter'. In this context, the term 'current rise time duration', also referred to as the pull-in time or ignition delay, corresponds to the time required for the current flowing through the primary winding 38 to rise from an inactive level to a predetermined level. In other words, the term 'current rise time duration' refers to the time from the start of supplying current to the primary winding 38 until the current flowing through the primary winding 38 reaches a first global maximum value.

[0036] In order to determine the parameters RR1 to RR4, the ignition system 30 is equipped with a current detector 44, which is arranged in the current path between the primary winding 38 and the control unit 36 ​​or the current source and is configured to determine the instantaneous value of the current flowing through the primary winding 38. The current detector 44 is connected to the control unit 36 ​​for sending the determined value thereto, such as Figure 1 As shown by the dotted line in .

[0037] Alternatively or additionally, these parameters may indicate a voltage rise time duration in the secondary winding 40 of the ignition coil 34. In this context, the term "voltage rise time duration" refers to the time required for the voltage across the spark plug 32 to rise from an inactive level to a predetermined level. To this end, the ignition system 30 may be equipped with a voltage detector coupled across the spark plug 32 and configured to determine an instantaneous value of the voltage across the spark plug 32. The voltage detector may be connected to the control unit 36 ​​for sending the determined value thereto.

[0038] Alternatively or additionally, these parameters may indicate spark time or spark duration. In this context, the term "spark time" refers to the point in time at which a spark is generated at the spark plug 32. Spark time may be expressed relative to a starting point of actuation of the starter spark plug. Thus, the term "spark duration" refers to the duration from a starting point of actuation of the starter spark plug 48 to a point in time at which a spark is generated. To determine spark time or spark duration, the voltage detector described above may be used.

[0039] Specifically, the parameters RR1 to RR4 may be expressed in the form of a dimensionless number, such as seconds, or in the form of a dimensionless number. For example, when expressed in the form of a dimensionless number, the parameters RR1 to RR4 may be determined based on a statistical mean and variance or standard deviation. In this way, the effects of the mean and standard deviation may be combined into a unique number for quantifying the parameters RR1 to RR4.

[0040] In step S2.1, a first parameter RR1 is determined during a pre-start mode of operation of the engine 10. Specifically, during the pre-start mode, the engine 10 is not yet running, i.e. the starting device neither drives the engine 10 nor combustion occurs in the combustion chamber 14. In other words, no compression occurs in the cylinder 12 during the engine pre-start mode. The engine pre-start mode may be used to prepare the engine 10 for operation, for example by pre-lubricating moving parts.

[0041] Then, in step S2.2, a second parameter RR2 is determined during the purge mode of the engine 10, during which the engine 10 is driven by the starting device to, for example, purge the intake passage 22, the combustion chamber 14, and the exhaust passage 26. Specifically, during the engine purge mode, the piston 16 reciprocates and compression occurs in the combustion chamber 14. The second parameter RR2 determined during the purge mode can be considered to be a quasi-optimal value of the parameter. This is because the average density between the electrodes of the spark plug 32 is lower than the average density in the operation or combustion mode of the engine 10, because no charging occurs in the engine purge mode, and therefore no combustion occurs in the combustion chamber 14. During correct operation of the engine 10 and the ignition system 30, that is, when no fault occurs, the duration of the current rise time in the purge mode is greater than that in the operation or combustion mode of the engine 10.

[0042] The engine cleaning mode and the corresponding step S2.2 may be performed specifically for large internal combustion engines 10, for example with a power output of more than 50 kW per cylinder, specifically 80 kW. Such engines 10 may be operated on ships or as a drive source for stationary power plants.

[0043] Thereafter, the method proceeds to decision step S2.3, in which the first and second parameters RR1, RR2 are compared with the corresponding threshold values ​​T RR1 、T RR2 In this step, it is determined whether the ignition system 30 is subject to any abnormality or failure indicating that the replacement detection or measurement cycle cannot be performed correctly. Specifically, when the first parameter RR1 is equal to or greater than the first threshold value T RR1 Or the second parameter RR2 is equal to or greater than the second threshold value T RR2 When the measurement period C iis not completed, and the method proceeds directly to step S3. However, if it is determined in step S2.3 that the first parameter RR1 is below the first threshold value T RR1 And the second parameter RR2 is lower than the second threshold value T RR2 , the method proceeds to step S2.4.

[0044] In a further development, the method can alternatively or additionally check in step S2.3 whether the first and second parameters RR1, RR2 are greater than a first and a second threshold value T RR1 、T RR2 In other words, in step S2.3, the control unit 36 ​​may check whether each of the first and second parameters RR1, RR2 is within an expected range. If this is the case, the method proceeds to step S.2.4. If the first and second parameters RR1, RR2, respectively, are outside the expected range, the method proceeds to step S3.

[0045] In step S2.4, an engine parameter EP is determined. The engine parameter EP indicates the operating condition of the engine. Specifically, the engine parameter indicates or corresponds to the engine load or the engine speed.

[0046] Thereafter, in a further step S2.5, the determined engine parameter EP is compared with a third threshold value T EP1 If the engine parameter EP determined during step S2.4 is equal to the third threshold value T EP1 , then the method proceeds to step S2.6. If the engine parameter EP is not equal to, that is, lower than the third threshold TEP1 , the method returns to step S2.4. In this way, only when the engine parameter EP reaches the third threshold value T EP1 , that is, when the engine 10 is operated at a predetermined first minimum engine load, the method proceeds to step S2.6. EP1 It may be expressed in the form of a range, so that when the engine parameter EP is within the range, the method proceeds to step S2.6.

[0047] In step S2.6, a third parameter RR3 is determined. This is performed during the first load operating mode, during which the engine 10 is driven at a speed corresponding to the value given by the third threshold value T EP1 The engine is operated at a preset first minimum engine load.

[0048] In the next step S2.7, the determined third parameter RR3 is compared with the fourth threshold value T RR3 The comparison is performed to determine an abnormal or faulty condition of the ignition system 30, which indicates that the replacement detection or measurement cycle cannot be performed correctly. Specifically, if it is determined that the third parameter RR3 is equal to or greater than the fourth threshold value TRR3 , the measurement cycle C is not completed i , and the method proceeds to step S3. However, if it is determined that the third parameter RR3 is lower than the third threshold value T RR3 , the method proceeds to step S2.8.

[0049] Step S2.8 corresponds to step S2.4. In step S2.9, the determined engine parameter EP is compared with the fifth threshold value T EP2 If the engine parameter EP determined during step S2.8 is equal to the fifth threshold value T EP2 , then the method proceeds to step S2.10. If the engine parameter EP is not equal to, that is, lower than the fifth threshold value T EP2 , the method returns to step S2.8. In this way, only when the engine parameter EP reaches the fifth threshold value T EP2 , ie when the engine 10 is operating at a predetermined second minimum engine load, the method proceeds to step S2.10.

[0050] In step S2.10, a fourth parameter RR4 is determined. This is performed during the second load operating mode, during which the engine 10 is driven at a speed corresponding to the value given by the fifth threshold value T EP2 The engine is operated at a preset second minimum engine load.

[0051] The third and fifth thresholds T EP1 、T EP2 The reference load points can be determined individually for the engine 10, for example by means of a load histogram, so that they correspond to a reference load of the engine 10 at which a difference in the rise time parameter can be identified between the condition with a new spark plug installed and the condition with a worn spark plug installed. Such a difference in the rise time parameter is only identifiable in a portion of the engine load spectrum. For example, these reference load points can be obtained and / or verified experimentally.

[0052] In the next step S2.11, after the determined first to fourth rise time parameters RR1 to RR4 are stored in the memory unit 42 of the control unit 36, the measurement cycle C is completed. i Specifically, the determined parameters RR1 to RR4 are stored in a data set format, wherein they are associated with the corresponding measurement period, i.e. during which they were determined. Figure 7 As shown, for example, the determined parameters RR1 to RR4 may be stored in a table form, such as a matrix form.

[0053] Figure 7A matrix for storing the determined parameters RR1 to RR4 included in the memory unit 42 is shown. In particular, in the depicted matrix, individual rows are associated with different rise time parameters RR1 to RR4, wherein individual columns are associated with different measurement periods C i Thus, after completing the measurement cycle C i When the complete column is filled, the data corresponding to the measurement period C is stored. i The control unit 36 ​​may be configured to store the determined parameters RR1 to RR4 associated with the most recent (e.g. the four most recent) measurement cycles. In this way, efficient use of the memory unit 42 may be ensured. To this end, the memory unit 42 may fill the matrix in a first-in-first-out manner.

[0054] In step S2, a measurement cycle C is performed. i Afterwards, the method proceeds to decision step S3, in which the measurement period C is determined. i has been completed, i.e. it is determined whether all rise time parameters RR1 to RR2 have been determined and stored in the memory unit 42. If the previous step S2 and thus the measurement cycle C i has not yet been completed, the method stops the routine by returning to step S1. However, if the previous step S2 and the measurement cycle C are determined i has been completed, the method proceeds to step S4.

[0055] In decision step S4, it is determined whether the control variable "i" is equal to or exceeds parameter "n". In this context, parameter "n" refers to the minimum number of measurement cycles that must be completed before the method can proceed to step S5. In the configuration shown, parameter n is equal to 4. Alternatively, parameter n can be any other positive integer, such as 2, 3, 5 or 6. If it is determined that the control variable i is lower than parameter n, the method stops the routine by proceeding to step S10. However, if it is determined that variable i is equal to or greater than parameter n, the method proceeds to step S5. By step S4, it is ensured that the measurement cycles used to determine the different parameters RR1-RR4 are executed and completed before executing the subsequent steps of the routine.

[0056] In step S5, the method determines a plurality of reference values, namely three reference values ​​RR4 C1-1，…，C1-3 , so that in the subsequent step S6 the fourth parameter RR4 determined C1 To this end, the data corresponding to the three previous measurement cycles RR4 are retrieved from the memory unit 42. C1-1，…，C1-3 The value of the associated fourth parameter can be obtained from Figure 4In the method step S5.1 shown in FIG. 1 , the parameter “j” represents a further control variable of the method. Specifically, different reference values ​​RR4 C1-1，…，C1-3 Each of the three subsequent measurement cycles C i-1，…i-3 The value of the fourth parameter RR4 determined during a different measurement cycle in the i The measurement cycle that has been executed previously.

[0057] Then, the method proceeds to step S6 of detecting replacement of a component of the ignition system 30. In this step, based on the most recent measurement cycle C i The fourth parameter RR4 determined during Ci With three reference values ​​RR4 C1-1，…，C1-3 To do this, Figure 4 As shown, the fourth parameter RR4 is then determined in step S6.1 Ci With three reference values ​​RR4 C1-1，…，C1-3 The difference between each of the RR4 If each of the differences thus determined is equal to or lower than the sixth threshold value T RR4 , then in step S6.2, replacement of components of the ignition system 30 is detected.

[0058] Thereafter, the method proceeds to a decision step S7, in which it is determined whether a replacement of a component has been detected in a previous step S6. If it is determined in a previous step S6 that a replacement of a component has not been detected, the routine is interrupted and the method proceeds to a step S10. However, if it is determined in a previous step S6 that a replacement of a component has been detected, the method proceeds to a step S8, in which a counter of the engine 10 is updated, in particular an operating hour counter or a counter indicating the work produced associated with one cylinder 12. In this way, the proposed method provides information about when a component of the ignition system 30 has been changed. Based on this information, an improved life prediction of the ignition system 30, i.e. its ignition coil 34 and / or its spark plug 32, can be achieved.

[0059] Figure 5 and 6 Another embodiment of a method for detecting replacement of a component of an ignition system 30 is disclosed. Figures 2 to 4 The depicted configuration is compared to the Figure 5 and Figure 6 The method is configured to detect replacement of the spark plug 32 based on a parameter indicative of the condition of the spark plug 32. Specifically, Figure 5 and Figure 6 Methods and Figures 2 to 4The method described in the embodiment differs from the method steps 2', 5' and 6' specified below. It should be noted that in the proposed method, Figure 5 and 6 The method steps 2', 5' and 6' described in the embodiment can alternatively or additionally be Figures 2 to 4 Steps 2, 5 and 6 of the method depicted are performed.

[0060] Specifically, in step S2', a measurement cycle C is performed. i To determine a parameter indicating the condition of the spark plug 32. Specifically, the parameter to be determined is referred to as a spark plug condition indicator (SSI) hereinafter. In sub-step S2.1', a rise time parameter RR indicating at least one of a current rise time duration in the primary winding 38, a voltage rise time duration in the secondary winding 40, and a spark time is determined. Specifically, step S2.1 may be performed when the engine 10 reaches a predetermined operating condition (e.g., a minimum load operating condition).

[0061] Thereafter, an operating condition parameter of the engine 10 is determined in step S2.2'. In particular, the operating condition parameter is the density of the fuel mixture at the time of ignition. In order to determine the operating condition parameter, the control unit 36 ​​may be connected to a pressure sensor (not shown) which is configured to determine the pressure prevailing in the combustion chamber 14. Based on the determined pressure, the control unit 36 ​​may be configured to calculate the density of the fuel mixture at the time of ignition.

[0062] Then, in step S2.3', the value of the SSI is determined based on the determined rise time parameter RR and the operating condition parameter. In particular, this can be performed based on a mathematical model, such as a three-dimensional diagram, according to which the value of the SSI is determined as a function of the determined rise time parameter RR and the determined operating condition parameter. In particular, the mathematical model can be defined and / or calibrated based on basic investigations, accelerated tests and / or actual behavior of the spark plug over time. The calibration can vary depending on the type of engine 10, its application and / or the ignition system 30.

[0063] Subsequently, in step S2.4', the determined SSI values ​​are stored in the memory unit 42 in a data set format, wherein the determined SSI values ​​are associated with the corresponding measurement period C i The association means during which the determined SSI values ​​are determined, for example, in a table form, for example in a matrix form, wherein the individual columns or rows are associated with different measuring cycles.

[0064] In step S5', the method determines a plurality of reference values, namely three reference values ​​SSI Ci-1，…，Ci-3 , so as to be consistent with the SSI determined in step S6' CiTo this end, the values ​​corresponding to the three previous measurement cycles C are retrieved from the memory unit 42. i-1，…，i-3 Associated reference value SSI Ci-1，…，Ci-3 , such as from Figure 6 In other words, different reference values ​​SSI Ci-1，…，Ci-3 Each of the three subsequent measurement cycles C i-1，…，i-3 The value of the parameter SSI determined during a different measurement cycle in C, i.e., in the most recent measurement cycle C i The measurement cycle that has been executed previously.

[0065] Then, the method proceeds to step S6' of detecting the replacement of the spark plug 32 of the ignition system 30. In this step, based on the most recent measurement cycle C i Parameters determined during SSI Ci With three reference values ​​SSI C1-1，…，C1-3 The comparison of the spark plug 32 is used to detect the replacement of the spark plug 32. Figure 6 As shown, the parameter SSI is then determined in step 6.1' Ci and three reference values ​​SSI C1-1，…，C1-3 The difference between each of them and the seventh threshold T SSI If each of the differences thus determined is equal to or lower than the seventh threshold value T SSI , then in step S6.2', the replacement of the spark plug 32 of the ignition system 30 is detected, such as Figure 6 shown.

[0066] It is obvious to those skilled in the art that these embodiments and projects only depict examples of multiple possibilities. Therefore, the embodiments shown here should not be understood to form restrictions on these features and configurations. Any possible combination and configuration of the features can be selected according to the scope of the present invention.

[0067] This is the case in particular with regard to the optional features, which can be combined in any technically feasible combination with some or all of the previously mentioned embodiments, items and / or features.

[0068] A method for detecting replacement of a component of an ignition system of a spark-ignition internal combustion engine may be provided. The method may include the steps of determining at least one parameter indicative of the operation or condition of the ignition system; and detecting replacement of the component based on a comparison of the parameter with at least one reference value.

[0069] In particular, the method may be provided such that the component whose replacement is to be tested is at least one of a spark plug and an ignition coil of the ignition system.

[0070] By detecting the replacement of a component of the ignition system, the proposed method provides information about when a component of the ignition system, such as a spark plug, has been replaced. Based on this information, the remaining life of the component of the ignition system can be determined, thereby contributing to improved life prediction. In particular, the proposed method can make it possible to automatically detect the replacement of a component of the ignition system and store information related thereto. Based on this information, the monitoring of the ignition system can be improved in order to more reliably prevent the engine from experiencing unplanned downtime.

[0071] The proposed method may be used in conjunction with any suitable spark-ignited internal combustion engine, i.e., an engine in which combustion of a fuel mixture is initiated by a spark generated within a combustion chamber (e.g., by a spark plug). For example, such an engine may be a gas engine, a dual-fuel engine, or any other type of Otto engine that uses a spark plug to ignite a fuel mixture within the engine combustion chamber. The engine may be used to power any machine or equipment, including ships or other marine applications, locomotive applications, highway trucks or vehicles, off-highway machines, generators, pumps, stationary equipment such as power plants, or other engine-powered applications.

[0072] The method may be executed in response to engine starting. Specifically, the step of determining at least one parameter may be initiated in response to engine starting.

[0073] The step of determining at least one parameter may comprise the sub-step of determining an engine parameter indicative of an operating condition of the engine. In particular, the parameter may represent the engine load or the engine speed. The method may be provided such that the step of determining at least one parameter is performed when the determined engine parameter has reached a predetermined threshold value. In this way, it may be ensured that the engine is operated at a predetermined load. It has been found that for some applications, the detection of component replacement is particularly advantageous in parts of the engine load spectrum. This may be taken into account by ensuring that the engine is operated at a predetermined load or within a predetermined load range when performing the step of determining at least one parameter.

[0074] Specifically, in the step of determining at least one parameter, a plurality of parameters may be determined. This may be performed during a measurement cycle. In other words, by performing a measurement cycle, a plurality of parameters may be determined. The plurality of parameters may be determined such that each of the plurality of parameters is determined during different engine operating conditions. Thus, different parameters determined during a measurement cycle may be associated with different engine operating conditions.

[0075] To this end, the step of determining at least one parameter may include the sub-step of determining a first parameter during an engine pre-start operating condition. Alternatively or additionally, the step of determining at least one parameter may include the sub-step of determining a second parameter during an engine purge condition. Alternatively or additionally, the step of determining at least one parameter may include the sub-step of determining at least one third parameter during a condition in which the engine has reached a minimum engine speed or engine load or is operating within a predetermined engine speed or load range.

[0076] Specifically, at least one parameter may indicate a current flowing through an ignition coil of the ignition system during spark plug actuation. Specifically, the parameter may indicate at least one of a current rise time duration in a primary winding of the ignition coil, a voltage rise time duration in a secondary winding of the ignition coil, and a spark time.

[0077] Alternatively or additionally, at least one parameter may be indicative of a condition of the spark plug, which is specifically determined based on at least one of the engine operating parameters, specifically the density of the fuel mixture at the ignition time, and the duration of the current rise time or spark time in the primary winding of an ignition coil of the ignition system.

[0078] In a further development, the step of determining at least one parameter may comprise a sub-step of storing the determined parameter in a data set on a memory unit, wherein the determined parameter may be associated with the respective measuring cycle, in particular in table or matrix form.

[0079] The method may be provided such that the step of determining at least one parameter is performed and at least two, in particular three, four or five measurement cycles are completed before the step of detecting replacement of a component is performed.

[0080] The method may comprise the further step of determining at least one reference value.The reference value may correspond to a value of a parameter determined during a previous or preceding measurement cycle, in particular compared to the measurement cycle during which the step of determining at least one parameter was performed.

[0081] In a further development, in the step of determining at least one reference value, a plurality of reference values, in particular at least three, four or five reference values, may be determined for at least one of the at least one parameter. Each of the reference values ​​associated with a parameter may correspond to a parameter value determined during a different one of a corresponding number of subsequent measurement cycles.

[0082] The method may be provided such that when the determined parameters and / or reference values ​​show a directional change in trend or magnitude, for example by comparing them to a threshold value, replacement of a component may be detected. By comparing a parameter to more than one reference value, system variance or other disturbances may be taken into account, thereby providing a robust method.

[0083] Further, in the step of detecting replacement of a component, a difference between the parameter and each of the at least one associated reference value may be determined, and wherein replacement of a component is detected based on the at least one determined difference, specifically based on a comparison of the at least one determined difference with a threshold value. Specifically, replacement of a component may be detected if each of the at least one determined difference exceeds the threshold value.

[0084] The method may comprise the further step of storing a replacement time, i.e. the time at which the replacement was detected. Further, the method may comprise providing a lifetime of the component, i.e. corresponding to a predicted lifetime of the component, e.g. in hours or produced work, based on the determined replacement time, e.g. by determining the difference between the replacement time and the time the component has been installed. In this way, when a replacement is detected, absolute operating hours may be recorded and stored. This may be used as a reference value for the associated component.

[0085] Furthermore, an ignition system for a spark-ignition internal combustion engine is provided. The ignition system may include a control unit configured to determine at least one parameter indicative of an operating condition of the ignition system and to detect replacement of a component of the ignition system based on a comparison of the parameter with at least one reference value.

[0086] Industrial Applicability

[0087] Referring to the drawings, a method for detecting replacement of a component of an ignition system 30 of a spark-ignition internal combustion engine 10 and an ignition system 30 are proposed. The method may be executed by a control unit 36 ​​of the ignition system 30.

[0088] The method and ignition system 30 as described above can be applied to any spark ignition reciprocating engine, especially gas or dual fuel engines. The proposed ignition system 30 can replace conventional ignition systems and can be used as a replacement or retrofit part.

Claims

1. A method for detecting replacement of a component of an ignition system (30) of a spark-ignition internal combustion engine (10), comprising the following steps: - determining at least one parameter (RR4; SSI) indicative of the operation of the ignition system (30) or indicative of at least one of the health condition, ageing condition and wear condition of the ignition system (30); as well as - based on the parameter (RR4; SSI) and at least one reference value (RR4 Ci-j ;SSI Ci-j ), wherein at least one parameter indicates a current flowing through an ignition coil (34) of the ignition system (30) during actuation of a spark plug (32), and wherein the reference value (RR4 Ci-j ;SSI Ci-j ) corresponds to the previous or preceding measurement cycle (C i-j ) during the measurement period, the value of the parameter (RR4; SSI) determined during the measurement period, the previous or preceding measurement period (C i-j ) is a measurement cycle (C ) during which the step (S2) of determining said at least one parameter (RR4; SSI) is performed i ) in comparison.

2. The method of claim 1, wherein the component of the ignition system (30) is at least one of a spark plug (32) and an ignition coil (34).

3. A method according to claim 1 or 2, wherein said step of determining said at least one parameter (RR4; SSI) is initiated in response to an engine start.

4. The method according to claim 1 or 2, wherein the step of determining the at least one parameter (RR4; SSI) comprises the sub-step of determining an engine parameter (EP) indicative of an operating condition of the engine (10), and wherein when the engine parameter (EP) has reached a predetermined threshold value (T EP2 ), at least one parameter (RR4; SSI) is determined.

5. The method according to claim 1 or 2, wherein in the step of determining the at least one parameter, during the measurement period (C i ) during which multiple parameters (RR1-4) associated with different engine operating conditions are determined.

6. The method according to claim 1 or 2, wherein the step of determining the at least one parameter comprises at least one of the following sub-steps: - determining a first parameter (RR1) during an engine pre-start mode; - determining a second parameter (RR2) during an engine purge mode; and - determining a third parameter (RR4; SSI) during an operating mode in which the engine (10) has reached a minimum engine speed or engine load.

7. The method of claim 1 or 2, wherein the parameter indicative of current flowing through an ignition coil (34) of the ignition system (30) during actuation of a spark plug (32) indicates at least one of a current rise time duration in a primary winding (38) of the ignition coil (34), a voltage rise time duration in a secondary winding (40) of the ignition coil (34), and a spark time.

8. The method of claim 1 or 2, wherein at least one parameter is indicative of a condition of the spark plug (32).

9. The method of claim 8, wherein the parameter indicative of the condition of the spark plug (32) is determined based on an engine operating parameter and at least one of a current rise time duration or a spark time in a primary winding (38) of the ignition coil (34) of the ignition system (30).

10. The method of claim 9, wherein the engine operating parameter is the density of the fuel mixture at ignition.

11. The method according to claim 1 or 2, wherein the step of determining the at least one parameter (RR4; SSI) comprises a sub-step (S2.11; S.2.4') of storing the determined parameter (RR4; SSI) in a data set on a memory unit (42), wherein the determined parameter (RR4; SSI) is associated with the corresponding measurement period (C i ) is associated with.

12. The method according to claim 1 or 2, wherein said step of determining said at least one parameter is performed and at least two measurement cycles are completed before performing said step of detecting said replacement of said component. The method according to claim 12 , wherein the at least two measurement periods are three or five measurement periods.

14. The method according to claim 1 or 2, further comprising determining the at least one reference value (RR4) of the parameter (RR4; SSI) Ci-j ;SSI Ci-j ), wherein a plurality of reference values ​​(RR4 ) are determined for at least one of the at least one parameter (RR4 ; SSI) Ci-j ;SSI Ci-j ), wherein the reference value (RR4) associated with a parameter (RR4; SSI) Ci-j ;SSI Ci-j ) corresponds to a corresponding number of subsequent measurement cycles (C i-j ) during different measurement cycles in ).

15. The method according to claim 1 or 2, wherein in the step of detecting the replacement of the component, the parameter (RR4; SSI) and the associated at least one reference value (RR4 Ci-j ;SSI Ci-j ) in each of the above aspects, and wherein the replacement of the component is detected based on at least one of the determined differences.

16. The method according to claim 15, wherein if each of the at least one determined difference exceeds a threshold value (T RR4 ; T SSI ), then detect the replacement of the component.

17. An ignition system (30) for a spark-ignition internal combustion engine (10), comprising a control unit (36) configured to determine at least one parameter (RR4; SSI) indicative of the operation of the ignition system (30) or indicative of at least one of the health, aging and wear conditions of the ignition system (30), and to determine a control unit (36) based on the parameter (RR4; SSI) and at least one reference value (RR4 Ci-j ;SSI Ci-j ) to detect replacement of a component of the ignition system (30), wherein at least one parameter indicates a current flowing through an ignition coil (34) of the ignition system (30) during actuation of a spark plug (32), and wherein the reference value (RR4 Ci-j ;SSI Ci-j ) corresponds to the previous or preceding measurement cycle (C i-j ) during the measurement period, the value of the parameter (RR4; SSI) determined during the measurement period, the previous or preceding measurement period (C i-j ) is a measurement period (C ) during which said at least one parameter (RR4; SSI) is determined i ) in comparison.

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