SYSTEM AND METHOD FOR DETECTING MACHINE KNOCKING AND MISIGINATION

Abstract

Method for providing a spark to a machine (10) comprising the following: Receiving an input from one or more machine sensors to a control device (12), and Commands via the control device (12) of the secondary closing, integrating, charging and discharging of an ignition coil (240) during a cylinder cycle in response to the input, wherein the commands are realized via a single conductor that provides electrical connection between the control device (12) and an ignition coil driver circuit, and The secondary connection provides a low-resistance electrical path between a first side of a primary coil of an ignition coil (240) and a second side of the primary ignition coil, characterized by the fact that the secondary closing is performed during a crankshaft interval of the machine (10) in which machine knocking is expected.

Description

Area

[0001] The present invention relates to a system and method for detecting engine knock and misfire in a gasoline engine. The system and method may be particularly useful for engines operating with lean and diluted mixtures. State of the art and brief description

[0002] A spark plug can provide energy to initiate combustion within a cylinder of an engine. Specifically, a voltage potential may develop across electrodes of a spark plug. If the voltage potential is greater than a threshold, a spark may be generated between the spark plug's electrodes, resulting in the ignition of an air-fuel mixture within a cylinder. The ignition of the air-fuel mixture provides engine torque and can result in engine knock. Engine knock can be generated when end gases of a cylinder air-fuel mixture ignite due to increases in temperature and pressure within the cylinder. The ignition of end gases can result in higher-frequency cylinder pressure oscillations that generate engine knock. An ignition coil secondary winding can be monitored using ion detection circuits to determine if engine knock is present.However, some higher-output ignition coils have higher-inductance windings, which can make engine knock detection more challenging. Furthermore, an ion signal can be integrated to estimate engine combustion quality or misfire.

[0003] Document DE 40 38 440 A1 describes a method for providing a spark to an engine, which comprises receiving an input from one or more engine sensors to a control device, and commanding, via the control device, the shunting, integrating, charging, and discharging of an ignition coil during a cylinder cycle in response to the input. Document DE 197 81 523 T5 describes a similar method, wherein the commanding is implemented via a single conductor providing an electrical connection between the control device and an ignition coil driver circuit.

[0004] Further prior art relating to the background of the invention is provided by the documents DE 41 15 305 A1 and DE 196 49 278 A1.

[0005] If a conductor is provided between a control device that issues ignition timing commands and ignition circuits for each command signal, the number of conductors in the system can rapidly increase. Furthermore, multiple circuits may need to be provided to determine spark timing, ignition coil shunts, and ion sensor output. Consequently, providing a desired level of ignition system sophistication may prove difficult and / or less reliable.

[0006] The present inventors have recognized the above-mentioned disadvantages and have developed a method for providing a spark to an engine, comprising: receiving an input from one or more engine sensors to a controller and commanding, via the controller, the shunting, charging, and discharging of an ignition coil during a cylinder cycle in response to the input, wherein the commanding is accomplished via a single conductor providing electrical connection between the controller and an ignition coil driver circuit.

[0007] By providing multiple ignition circuit commands over a single conductor, it may be possible to reduce the number of conductors between a controller and ignition circuits. The reduced number of conductors can reduce wiring problems and lower system costs. Furthermore, a smaller number of conductors within the engine system can improve vehicle reliability. In particular, a single conductor positioned between a controller and an ignition circuit can carry three or more coded voltage pulses that provide ignition timing, ignition coil shunt timing, and ion signal integration timing. The voltage pulses are carried by the single conductor during one cycle of the engine such that ignition, ignition coil shunting, and ion signal integration can be performed during a single cylinder cycle.Furthermore, the pulses of each engine cycle can be changed to adjust the spark timing, adjust the ignition coil shunt timing, and adjust the ion signal integration timing.

[0008] The present description may offer several advantages. In particular, the approach reduces the number of conductors in a machine system. Furthermore, the approach may improve system reliability by reducing the number of electrical system connections in the system. Furthermore, the approach may simplify the circuits for decoding ignition timing, ignition coil shunting, and ion signal integration because only a single decoding circuit is used to determine the ignition system timing signals sent via a controller.

[0009] The above advantages and other advantages and features of the present description will be readily apparent from the following detailed description, considered alone or in conjunction with the accompanying drawings.

[0010] It should be understood that the above summary is provided to introduce, in simplified form, a selection of concepts further described in the detailed description. It is not intended to identify key or essential features of the claimed subject matter, the scope of which is defined solely by the claims following the detailed description. Furthermore, the claimed subject matter is not limited to implementations that address any disadvantages noted above or in any part of the present disclosure. Short description of the drawings

[0011] The advantages described herein will be better understood by reading an example, called the “Detailed Description,” alone or with reference to the drawings, in which: Fig. 1 is a schematic representation of a machine, Fig. 2 is a schematic representation of an ignition system, Fig. 3 to 5 are exemplary illustrations showing the operation of the ignition system of the Fig. 2 in accordance with the procedure of Fig. 6 show, Fig. 6 shows a method for providing multiple ignition system commands from a control device to an ignition circuit via a single conductor, and Fig. Figure 7 shows a representation of the ignition system commands and ion signal integration for normal and late combustion. Detailed description

[0012] The present description relates to the operation of an ignition system of a spark-ignition engine. In one non-limiting example, a control signal comprising a plurality of voltage pulses during a cylinder cycle is delivered to an ignition coil module via a single wire. The ignition coil module can selectively charge and discharge an ignition coil in response to voltage pulses. Further, coil shunt and ion signal integration commands can be delivered via voltage pulses over the same single wire or conductor. Fig. 1 shows an exemplary engine and an exemplary ignition system. Fig. 2 shows a more detailed view of the ignition system used in Fig. 1. Exemplary ignition system control sequences are shown in the Fig. 3 to 5. A method for providing coded ignition signals over the single wire is shown in Fig. 6 shown.

[0013] With reference to Fig. 1, the internal combustion engine 10 comprises a plurality of cylinders, one of which, in Fig. 1, is controlled by the electronic engine control device 12. The engine 10 includes a combustion chamber 30 and cylinder walls 32, with a piston 36 positioned therein and connected to a crankshaft 40. The combustion chamber 30 is shown communicating with the intake manifold 44 and the exhaust manifold 48 via the intake valve 52 and the exhaust valve 54, respectively. Both the intake and exhaust valves may be operated by an intake cam 51 and an exhaust cam 53. The position of the adjustable intake cam 51 may be determined by an intake cam sensor 55. The position of the adjustable exhaust cam 53 may be determined by an exhaust cam sensor 57.

[0014] The fuel injector 66 is shown positioned to inject fuel directly into the cylinder 30, known to those skilled in the art as direct injection. Alternatively, fuel may be injected into an intake port, known to those skilled in the art as port injection. The fuel injector 66 delivers liquid fuel in proportion to the pulse width of a signal from the controller 12. Fuel is supplied to the fuel injector 66 by a fuel system (not shown) that includes a fuel tank, a fuel pump, and a fuel rail (not shown). The intake manifold 44 is further shown in communication with an optional electronic throttle 62 that adjusts a position of a throttle plate 64 for controlling airflow from an air intake 42 to the intake manifold 44.

[0015] A distributorless ignition system 88 provides an ignition spark to the combustion chamber 30 via a spark plug 92 in response to the controller 12. A UEGO (Universal Exhaust Gas Oxygen) sensor 126 is shown coupled to the exhaust manifold 48 upstream of a catalyst 70. Alternatively, the UEGO sensor 126 may be replaced with a dual-state oxygen sensor.

[0016] In one example, the catalyst 70 may include multiple catalyst bricks. In another example, multiple emission control devices, each with multiple bricks, may be used. In one example, the catalyst 70 may be a three-way catalyst.

[0017] In the presentation of the Fig. 1, the controller 12 is shown as a conventional microcomputer including a microprocessor unit (CPU) 102, input / output (I / O) ports 104, read-only memory (ROM) (e.g., non-volatile memory) 106, random access memory (RAM) 108, retained memory (KAM) 110, and a conventional data bus.Controller 12 is shown receiving, in addition to the signals discussed above, various signals from sensors coupled to engine 10, including engine coolant temperature (ECT) from temperature sensor 112 coupled to cooling sleeve 114; a position sensor 134 coupled to accelerator pedal 130 for sensing force applied by foot 132; an intake manifold pressure (MAP) measurement from pressure sensor 122 coupled to intake manifold 44; an engine position sensor from Hall effect sensor 118 that senses the position of crankshaft 40; a measurement of air mass entering the engine from sensor 120; and a measurement of throttle position from sensor 58. Barometric pressure may also be sensed (sensor not shown) for processing by controller 12.In one aspect of the present description, the engine position sensor 118 generates a predetermined number of evenly spaced pulses during each revolution of the crankshaft from which the engine speed (RPM) can be determined.

[0018] In some examples, the engine may be coupled to an electric motor / battery system in a hybrid vehicle. The hybrid vehicle may have a parallel configuration, a series configuration, or a variation or combination thereof. Furthermore, in some examples, other engine configurations may be employed; for example, the engine may be turbocharged or supercharged.

[0019] During operation, each cylinder within the engine 10 typically experiences a four-stroke cycle: the cycle includes the intake stroke, the compression stroke, the power stroke, and the exhaust stroke. During the intake stroke, the exhaust valve 54 generally closes and the intake valve 52 opens. Air is introduced into the combustion chamber 30 via the intake manifold 44, and the piston 36 moves to the bottom of the cylinder to increase the volume within the combustion chamber 30. The position where the piston 36 is near the bottom of the cylinder and at the end of its stroke (for example, when the combustion chamber 30 is at its largest volume) is typically referred to by those skilled in the art as bottom dead center (BDC). During the compression stroke, the intake valve 52 and the exhaust valve 54 are closed. The piston 36 moves toward the cylinder head to compress the air in the combustion chamber 30.The point at which the piston 36 is at the end of its stroke and closest to the cylinder head (for example, when the combustion chamber 30 is at its smallest volume) is generally referred to by those skilled in the art as top dead center (TDC). In an event referred to as injection, fuel is introduced into the combustion chamber. In an event referred to as ignition, the injected fuel is ignited by a known ignition means, such as a spark plug 92, resulting in combustion. During the power stroke, the expanding gases push the piston 36 back to BDC. The crankshaft 40 converts piston movement into rotating shaft torque. Finally, during the exhaust stroke, the exhaust valve 54 opens to release the combusted air-fuel mixture to the exhaust manifold 48, and the piston returns to TDC.It should be noted that the above is shown only as an example and that the timing of opening and / or closing of the intake and exhaust valves may vary to provide positive or negative valve overlap, late closing of the intake valve, or various other examples.

[0020] With reference to Fig. 2, an illustration of an exemplary ignition system 88 is shown. In this example, the controller 12 receives sensed ion data from separate and remote ignition circuits 201 via a conductor or wire 231. The controller 12 provides command voltage pulses to the remote ignition circuits 201 via the single wire or conductor 233. In one example, the ignition circuits 201 may be incorporated into a coil mounted on top of a spark plug. The ignition system 88 also includes ion sensing circuits 225 for judging whether or not the engine 10 is experiencing engine knock or misfire. The ignition coil 240 provides electrical energy from the battery 220 to selectively create a spark at the spark plug 92. The battery 220 is connected to ground 280.

[0021] The ignition circuits 201 include an ion signal amplifier 202 that increases the magnitude of an analog ion signal provided by the ion detection circuits 225. The ion signal from the ion detection circuits 225 is also provided to the ion signal integrator circuit 206, which integrates an ion signal over an engine crankshaft time or window to provide a basis for indicating combustion quality or misfire. The ion signal integrator circuit 206 integrates the ion signal during a duration based on short-duration voltage pulses provided by the controller during a cylinder cycle (for example, COPID pulses between time T12 and time T17, as shown in Fig. 4). By appropriately selecting the integration period, the controller is able to distinguish between normal and retarded combustion ignition timing. Retarded combustion occurs after the integration period. The integrated value is an indication of combustion quality, and the integrated value is fed back to the controller by opening switch 211. Switch 211 increases the current flow in conductor 233 to provide a high current consumption state by activating current source 210 when switch 211 is closed. Current source 208 provides a low current consumption state when switch 211 is open. At the beginning of the dwell period, switch 211 is closed and the current is at a high level. During the dwell period, a second integrator in circuit 206 integrates at a constant rate.When both integrated values ​​are equal, switch 211 opens and the current goes to a lower level. The controller determines the integrated value by measuring the time from the start of the dwell time to the time the current is switched to a lower value.

[0022] The ignition circuits 201 also include voltage pulse decoder circuits 204 that generate three output signals from voltage pulses carried by conductor 233. In particular, the voltage decoder circuits 204 include combinational logic to provide a dwell time signal for charging and discharging the ignition coil 240. The voltage decoder circuits 204 also include combinational logic to provide an ignition coil shunt signal and an ion signal integration period signal. The voltage decoder circuits 204 direct the dwell signal to an insulated-gate bipolar transistor (IGBT) 252 via resistor 250 and conductor 251.

[0023] The voltage decoder circuits 204 direct the ignition coil shunt signal to a metal oxide field effect transistor (MOSFET) 234 via conductor 235. The voltage decoder circuits 204 direct the ion integration period signal to the ion signal integrator circuit 206 via conductor 207.

[0024] The ignition coil 240 has a primary winding 242 and a secondary winding 244. The primary winding 242 has a first side 243 electrically coupled to the battery 220 and a second side 241 electrically coupled to the collector 255 of the IGBT 252. The MOSFET 234 is in electrical connection with the first side 243 at the source (S) and with the second side 241 at the drain (D). During shunting, current flows from 241 to 243. A low-resistance electrical path is provided between the drain (D) and source (S) of the MOSFET 234 when a higher voltage (for example, 5 V higher than the MOSFET source (S)) is applied to the gate (G) of the decoder circuits 204. A high resistance electrical path (e.g., open circuit) is provided between the drain (D) and source (S) of the MOSFET 234 when a lower voltage (e.g., 0 V or ground) is applied to the gate (G) from the decoder circuits 204.A shunt can thus be provided between the first side 243 and the second side 241 by applying a higher voltage to the gate (G). By shunting the primary winding 242, it may be possible to improve the gain of ion detection, so that engine knock detection and misfire detection are also improved when the secondary winding 244 has a high inductance. A first side 246 of the secondary winding 244 is electrically coupled to ion detection circuits 225. The ion detection circuits are electrically coupled to the battery 220. A second side 245 of the secondary winding 244 is electrically coupled to the spark plug 92.

[0025] The spark plug 92 has a first electrode 260 and a second electrode 262. An air gap 264 is provided between the first electrode 260 and the second electrode 262. A spark can develop in the air gap 264 when the IGBT is switched from on (e.g., closed switch) to off (e.g., open switch).

[0026] The IGBT 252 has a transmitter 253, a base 254, and a collector 255. The current flow from the decoder circuit 204 to the IGBT 254 is limited by the resistor 250. The IGBT 252 is on (e.g., closed switch) when a higher voltage (e.g., 5 V) is applied to the base 254 by the decoder circuit 204. The IGBT 252 is off (e.g., open switch) when a lower voltage (e.g., 0 V or ground) is applied to the base 254 by the decoder circuit 204. By closing the IGBT 252, current flows from the battery 220 through the primary coil 242 to charge the ignition coil 240. Opening the IGBT 252 after charging the primary coil 242 can cause the ignition coil 240 to discharge, thereby inducing a spark at the spark plug 96. In this way, a spark can be delivered to an engine cylinder via the spark plug 92.

[0027] The ion sensor circuits 225 are electrically coupled to the first side 246 of the secondary winding 244 and the battery 220. The ion sensor circuits 225 include the Zener diode 230, diode 226, diode 220, capacitor 228, resistor 222, and resistor 224. The output of the ion detection circuits is a node between the diode 226 and the Zener diode 230. The ion circuit output is provided to an ion amplifier 202 and an ion integration circuit 206.

[0028] The ignition system 88 therefore provides functionality to deliver a spark to a cylinder, detect ions, integrate an ion signal, and shunt an ignition coil to enhance ion detection. Ion detection may provide an indication of engine knock and / or misfire. Commands for ion detection and ignition control may be delivered over a single conductor or wire, allowing an engine controller to interface with the ignition circuits. The circuits may thus provide enhanced capability without increasing the electrical connections between the controller and the ignition circuit.

[0029] The system of Fig. 1 and Fig. 2 provides for providing a spark to a machine, the system comprising: a controller; an ignition circuit having a pulse decoding circuit and an ion integration circuit; a single conductor electrically coupling the controller and the ignition coil pre-driver circuit; an ignition coil having a primary coil; and an ignition coil shunt switch in electrical communication with the pulse decoding circuit. The system further includes a controller having executable instructions stored in non-volatile memory to command spark timing, ignition coil shunting, and ion signal integration over the single conductor. The system has executable instructions stored in non-volatile memory to output a spark timing voltage pulse and an ignition coil shunting voltage pulse.The system includes the ignition coil shunt switch electrically coupled to a first side of the primary coil and to a second side of the primary coil. The system further includes a controller having executable instructions stored in non-volatile memory for providing a voltage pulse to command spark timing, a voltage pulse to command ignition coil shunting, and a voltage pulse to command ion signal integration. The system further includes an ignition spark switch in electrical communication with the pulse decoding circuit.

[0030] With reference to Fig. Figure 3 is a diagram illustrating control signals for an ignition system that provides a spark to an engine cylinder during a cycle of an engine. The diagram shows an encoded COPID signal 309 for commanding and providing spark timing and ion signal integration and / or ignition coil shunt timing. COPID 309 is a coil-to-spark plug control signal for ignition timing and ion signal integration / coil shunt timing for an engine cylinder during a cycle of the cylinder. The spark timing and ion signal integration and / or ignition coil shunt timing are encoded in three voltage pulses. The COPID signal 309 is provided by the controller to the ignition circuits.

[0031] The ignition dwell time (e.g., the time during which the ignition coil is charged) is shown in relation to the COPID signal 309 at the timing of window 302. The ignition coil shunt timing window and / or ion integration window in relation to the COPID signal 309 is shown at the timing of window 304. The vertical axis represents the level of the COPID signal (e.g., the voltage level), and the COPID signal becomes active at a higher level near the vertical axis arrow. The COPID signal does not become active at a lower level near the horizontal axis. The horizontal axis represents time, and time decreases from the left side of Fig. 3 to the right side of Fig. 3. The double S marks along the horizontal axis represent interruptions in time, which can be long or short.

[0032] At time T0, the COPID signal 309 is low and inactive. The ignition coil is not charged, and the ignition coil is neither shunted nor integrated with the ion signal. The engine cylinder selected to receive a spark based on the COPID signal 309 may have received a spark during a previous cycle of the cylinder.

[0033] At time T1, the COPID signal 309 transitions high to begin an ignition dwell command period, during which charging of the ignition coil is commanded. Shortly thereafter, the dwell period 302 begins, during which the ignition coil begins charging in response to the ignition dwell command provided by the COPID signal 309 at time T1. In one example, there is a 120 microsecond delay between the rising edge of the COPID signal 309 at time T1 and the beginning of the dwell period 302 at 301. The ion sensor output is neither integrated nor is the ignition coil shunted at time T1.

[0034] At time T2, the COPID signal 309 transitions to a lower level to end the ignition dwell command period. The end time at T2 may correspond to a specific engine crankshaft angle at which spark ignition is desired (for example, 20 degrees before the compression stroke dead center for the cylinder receiving the spark). The dwell period 302 ends at 303, which may be delayed 45 microseconds from the falling edge of the COPID signal 309 at time T2. The time between time T1 and time T2 is the dwell time (for example, ignition coil charging time) and may range between 1.5 and 2.5 milliseconds.

[0035] At time T3, signal 309 transitions to a higher level to provide information for ion integration and / or ignition coil shunt timing. In some examples, ion integration and ignition coil shunt timing may be provided based on a single window, as shown at 304. In other examples, the timing of window 304 may be based only on ion integration or only on ignition coil shunting. The dwell voltage pulse between time T1 and time T2 has expired at time T3. Ion integration and / or ignition coil shunting are not active at time T3.

[0036] At time T4, signal 309 transitions to a lower level to provide a short-duration voltage pulse that identifies that ion integration and / or ignition coil shunt timing information is being provided from the controller to the ignition circuits. In one example, ion integration and / or ignition coil shunt timing voltage pulses may last approximately 75 microseconds to distinguish these voltage pulses from dwell timing voltage pulses. Shortly thereafter, ion current integration and / or ignition coil shunt timing window 304 opens to begin ion current integration and / or ignition coil shunting. In one example, the time from T3 until the ion current integration and / or ignition coil shunt window opening opens is 120 microseconds.This time allows the ion integration and / or ignition coil shunt timing voltage pulse to complete before ion integration and / or ignition coil shunting begins.

[0037] At time T5, signal 309 transitions to a higher level to provide a short-duration voltage pulse that identifies that ion integration and / or ignition coil shunt timing information is being provided from the controller to the ignition circuits. The pulse duration between time T5 and time T6 is 75 microseconds. This second ion integration and / or ignition coil shunt timing voltage pulse identifies the end timing of the ion integration period and / or ignition coil shunt timing. Shortly after time T6, ion current integration and / or ignition coil shunt window 304 closes to terminate ion current integration and / or ignition coil shunting. In one example, ion current integration and / or ignition coil shunt window 304 closes 120 microseconds after the rising edge of the third voltage pulse at time T5.

[0038] In this way, ignition coil dwell time, spark time, ion current integration period, and / or ignition coil shunt period or timing can be provided to the ignition circuits via three voltage pulses delivered over a single wire or conductor. The voltage pulses are provided by the controller and delivered to the ignition circuits. The timing of the three voltage pulses can be based on the engine crankshaft angle. Time T2, for example, can be a desired spark timing angle, and the ion current integration and / or ignition shunt window can open at a first desired engine crankshaft angle and close at a second desired engine crankshaft angle.

[0039] With reference to Fig. 4 shows a second diagram illustrating control signals for an ignition system that delivers a spark to an engine cylinder during a cycle of an engine. The diagram shows an encoded COPID signal 411 for providing spark timing and ion signal integration and / or ignition coil shunt timing. COPID 411 is a coil-to-spark plug control signal for ignition timing and ion signal integration / coil shunt timing for an engine cylinder during a cycle of the cylinder. The spark timing and ion signal integration and / or ignition coil shunt timing are encoded in four voltage pulses. The COPID signal 411 is provided by the controller to the ignition circuits. In this example, the ion signal integration and / or ignition coil shunt timing are provided in two differently timed windows 412 and 414.The ion signal integration timing window may be 412 and the ignition coil shunt timing window may be 414, or vice versa.

[0040] The ignition dwell time (e.g., the time during which the ignition coil is charged) is shown relative to the COPID signal 411 at the timing of window 410. The first ignition coil shunt timing window and / or ion integration window relative to the COPID signal 411 is shown at the timing of window 412. The second ignition coil shunt timing window and / or ion integration window relative to the COPID signal 411 is shown at the timing of window 414. The first ignition coil shunt timing window and / or ion integration window 412 has the same start time as the second ignition coil shunt timing window and / or ion integration window 414. The vertical axis represents the level of the COPID signal (e.g., the voltage level), and the COPID signal becomes active at a higher level near the vertical axis arrow. The COPID signal does not become active at a lower level near the horizontal axis.The horizontal axis represents time, and time decreases from the left side of . Fig. 4 to the right side of Fig. 4. The double S marks along the horizontal axis represent interruptions in time, which can be long or short.

[0041] At time T9, the COPID signal 411 is low and inactive. The ignition coil is not charged, and the ignition coil is neither shunted nor integrated with the ion signal. The engine cylinder selected to receive a spark based on the COPID signal 411 may have received a spark during a previous cycle of the cylinder.

[0042] At time T10, the COPID signal 411 transitions high to begin an ignition dwell command period, during which charging of the ignition coil is commanded. Shortly thereafter, the dwell period 410 begins, during which the ignition coil begins charging in response to the ignition dwell command provided by the COPID signal 411 at time T10. In one example, there is a 120 microsecond delay between the rising edge of the COPID signal 411 at time T10 and the beginning of the dwell period 410 at 401. The ion sensor output is neither integrated nor is the ignition coil shunted at time T10.

[0043] At time T11, the COPID signal 411 transitions to a lower level to end the ignition dwell command period. The end time at T11 may correspond to a specific engine crankshaft angle at which spark ignition is desired (for example, 20 degrees before the compression stroke of top dead center for the cylinder receiving the spark). The dwell period 410 ends at 403, which may be delayed 45 microseconds from the falling edge of the COPID signal 411 at time T11. The time between time T10 and time T11 is the dwell time (for example, ignition coil charging time) and may range between 1.5 and 2.5 milliseconds.

[0044] At time T12, signal 411 transitions to a higher level to provide information for ion integration and / or ignition coil shunt timing. In some examples, ion integration and ignition coil shunt timing may be provided based on two windows, as shown at 412 and 414. The timing of window 412 may be the basis for only ion integration or only ignition coil shunting. Likewise, the timing of window 414 may be the basis for only ion integration or only ignition coil shunting. The dwell voltage pulse between time T10 and time T11 has expired at time T12. Ion integration and / or ignition coil shunting are not active at time T12.

[0045] At time T13, signal 411 transitions to a lower level to provide a short-duration voltage pulse that identifies that ion integration and / or ignition coil shunt timing information is being provided from the controller to the ignition circuits. In one example, ion integration and / or ignition coil shunt timing voltage pulses may last approximately 75 microseconds to distinguish these voltage pulses from dwell timing voltage pulses. Shortly thereafter, ion current integration and / or ignition coil shunt timing windows 412 and 414 open to begin ion current integration and ignition coil shunting. In one example, the time from T12 until the ion current integration and / or ignition coil shunt window opening opens is 120 microseconds.This time allows the ion integration and / or ignition coil shunt timing voltage pulse to complete before ion integration and / or ignition coil shunting begins.

[0046] At time T14, signal 411 transitions to a higher level to provide a short-duration voltage pulse that identifies that ion integration and / or ignition coil shunt timing information is being provided from the controller to the ignition circuits. The pulse duration between time T14 and time T15 is 75 microseconds. This second ion integration and / or ignition coil shunt timing voltage pulse identifies the end timing of the first ion integration period and / or the first ignition coil shunt timing window 412. Shortly after time T15, the ion current integration and / or ignition coil shunt window 412 closes to terminate ion current integration and / or ignition coil shunting. In one example, the ion current integration and / or ignition coil shunt closing window 412 closes 120 microseconds after the rising edge of the third voltage pulse at time T14.The second ion integration period and / or ignition coil shunt timing window 414 remains open so that ion current integration or ignition coil shunting can continue.

[0047] At time T16, signal 411 transitions to a higher level to provide a short-duration voltage pulse that identifies that ion integration and / or ignition coil shunt timing information is being provided from the controller to the ignition circuits. The pulse duration between time T16 and time T17 is 75 microseconds. This third ion integration and / or ignition coil shunt timing voltage pulse identifies the end timing of the second ion integration period and / or the second ignition coil shunt timing window 414. Shortly after time T17, the ion current integration and / or ignition coil shunt window 414 closes to terminate ion current integration and / or ignition coil shunting. In one example, the ion current integration and / or ignition coil shunt closing window 414 closes 120 microseconds after the rising edge of the fourth voltage pulse at time T16.Therefore, the first and second ion integration period and / or ignition coil shunt timing windows 412 and 414 are closed.

[0048] In this way, ignition coil dwell time, spark time, ion current integration period, and / or ignition coil shunt period or timing may be provided to the ignition circuits via four voltage pulses delivered over a single wire or conductor. The voltage pulses are provided by the controller and delivered to the ignition circuits. The timing of the four voltage pulses may be based on the engine crankshaft angle. For example, time T11 may be a desired spark timing angle, and the ion current integration and / or ignition shunt window may open at a first desired engine crankshaft angle and close at a second desired engine crankshaft angle. The four voltage pulses allow for different end times between windows 412 and 414 so that ignition coil shunting may be separate from ion current integration.

[0049] With reference to Fig. 5 shows a third diagram illustrating control signals for an ignition system that provides a spark to an engine cylinder during a cycle of an engine. The diagram shows an encoded COPID signal 511 for providing spark timing and ion signal integration and / or ignition coil shunt timing. COPID 511 is a coil-to-spark plug control signal for ignition timing and ion signal integration / coil shunt timing for an engine cylinder during a cycle of the cylinder. The spark timing and ion signal integration and / or ignition coil shunt timing are encoded in five voltage pulses. The COPID signal 511 is provided by the controller to the ignition circuits. In this example, the ion signal integration and / or ignition coil shunt timing are provided in two differently timed windows 522 and 524.Timing windows 522 and 524 have different start and stop times. The ion signal integration timing window may be 522, and the ignition coil shunt timing window may be 524, or vice versa.

[0050] The ignition dwell time (e.g., the time during which the ignition coil is charged) is shown relative to the COPID signal 511 at the timing of window 520. The first ignition coil shunt timing window and / or ion integration window relative to the COPID signal 511 is shown at the timing of window 522. The second ignition coil shunt timing window and / or ion integration window relative to the COPID signal 511 is shown at the timing of window 524. The first ignition coil shunt timing window and / or ion integration window 522 has a different start and stop time than the second ignition coil shunt timing window and / or ion integration window 524. The vertical axis represents the level of the COPID signal (e.g., the voltage level), and the COPID signal becomes active at a higher level near the vertical axis arrow.The COPID signal does not become active at a lower level near the horizontal axis. The horizontal axis represents time, and time decreases from the left side of . Fig. 5 to the right side of Fig. 5. The double S marks along the horizontal axis represent interruptions in time, which can be long or short.

[0051] At time T19, the COPID signal 511 is low and inactive. The ignition coil is not charged, and the ignition coil is neither shunted nor integrated with the ion signal. The engine cylinder selected to receive a spark based on the COPID signal 511 may have received a spark during a previous cycle of the cylinder.

[0052] At time T20, the COPID signal 511 transitions high to begin an ignition dwell command period, during which charging of the ignition coil is commanded. Shortly thereafter, the dwell period 520 begins, during which the ignition coil begins charging in response to the ignition dwell command provided by the COPID signal 511 at time T20. In one example, there is a 120 microsecond delay between the rising edge of the COPID signal 511 at time T20 and the beginning of the dwell period 520 at 501. The ion sensor output is neither integrated nor is the ignition coil shunted at time T20.

[0053] At time T21, the COPID signal 511 transitions to a lower level to end the ignition dwell command period. The end time at T21 may correspond to a specific engine crankshaft angle at which spark ignition is desired (for example, 20 degrees before the compression stroke of top dead center for the cylinder receiving the spark). The dwell period 520 ends at 513, which may be delayed 45 microseconds from the falling edge of the COPID signal 511 at time T21. The time between time T20 and time T21 is the dwell time (for example, ignition coil charging time) and may range between 1.5 and 2.5 milliseconds.

[0054] At time T22, signal 511 transitions to a higher level to provide information for ion integration and / or ignition coil shunt timing. In some examples, ion integration and ignition coil shunt timing may be provided based on two windows, as shown at 522 and 524. The timing of window 522 may be the basis for only ion integration or only ignition coil shunting. Likewise, the timing of window 524 may be the basis for only ion integration or only ignition coil shunting. The dwell voltage pulse between time T20 and time T21 has expired at time T22. Ion integration and / or ignition coil shunting are not active at time T22.

[0055] At time T23, signal 511 transitions to a lower level to provide a short-duration voltage pulse that identifies that ion integration and / or ignition coil shunt timing information is being provided from the controller to the ignition circuits. In one example, ion integration and / or ignition coil shunt timing voltage pulses may last approximately 75 microseconds to distinguish these voltage pulses from dwell timing voltage pulses. Shortly thereafter, ion current integration and / or ignition coil shunt timing window 522 opens to begin ion current integration and / or ignition coil shunting. In one example, the time from T22 until the ion current integration and / or ignition coil shunt window opening opens is 120 microseconds.This time allows the ion integration and / or ignition coil shunt timing voltage pulse to complete before ion integration and / or ignition coil shunting begins.

[0056] At time T24, signal 511 transitions to a higher level to provide a short-duration voltage pulse that identifies that ion integration and / or ignition coil shunt timing information is being provided from the controller to the ignition circuits. The pulse duration between time T24 and time T25 is 75 microseconds. This second ion integration and / or ignition coil shunt timing voltage pulse identifies the start timing of the second ion integration period and / or the second ignition coil shunt timing window 524. Shortly after time T25, the ion current integration and / or ignition coil shunt window 524 opens to begin ion current integration and / or ignition coil shunting. In one example, the ion current integration and / or ignition coil shunt window 524 opens 120 microseconds after the rising edge of the third voltage pulse at time T24.The first ion integration period and / or ignition coil shunt timing window 522 remains open so that ion current integration or ignition coil shunting can continue.

[0057] At time T26, signal 511 transitions to a higher level to provide a short-duration voltage pulse that identifies that ion integration and / or ignition coil shunt timing information is being provided from the controller to the ignition circuits. The pulse duration between time T26 and time T27 is 75 microseconds. This fourth ion integration and / or ignition coil shunt timing voltage pulse identifies the end timing of the first ion integration period and / or the first ignition coil shunt timing window 522. Shortly after time T27, the ion current integration and / or ignition coil shunt window 522 closes to terminate ion current integration and / or ignition coil shunting. In one example, the ion current integration and / or ignition coil shunt closing window 522 closes 120 microseconds after the rising edge of the fourth voltage pulse at time T26.Therefore, the first ion integration period and / or ignition coil shunt timing window 522 is closed.

[0058] At time T28, signal 511 transitions to a higher level to provide a short-duration voltage pulse that identifies that ion integration and / or ignition coil shunt timing information is being provided from the controller to the ignition circuits. The pulse duration between time T28 and time T29 is 75 microseconds. This fifth ion integration and / or ignition coil shunt timing voltage pulse identifies the end timing of the second ion integration period and / or the second ignition coil shunt timing window 524. Shortly after time T29, the ion current integration and / or ignition coil shunt window 524 closes to terminate ion current integration and / or ignition coil shunting. In one example, the ion current integration and / or ignition coil shunt closing window 524 closes 120 microseconds after the rising edge of the fifth voltage pulse at time T28.Therefore, the second ion integration period and / or ignition coil shunt timing window 524 is closed.

[0059] In this way, ignition coil dwell time, spark time, ion current integration period, and / or ignition coil shunt period or timing may be provided to the ignition circuits via five voltage pulses delivered over a single wire or conductor. The voltage pulses are provided by the controller and delivered to the ignition circuits. The timing of the five voltage pulses may be based on the engine crankshaft angle. For example, time T21 may be a desired spark timing angle, and the ion current integration and / or ignition shunt window may open at a first and second desired engine crankshaft angle and close at different desired engine crankshaft angles. The five voltage pulses allow for different start and end times between windows 522 and 524, so that ignition coil shunting may be separate from ion current integration.

[0060] With reference to Fig. 6 describes a method for encoding spark timing, ion signal integration, and ignition coil primary winding shunts over a single conductor or wire. The ignition system may be similar to the ignition system described in Fig. 2. In addition, at least portions of the method of Fig. 6 as executable instructions in the system of Fig. 1 and Fig. 2. Furthermore, at least parts of the procedure of the Fig. 6 measures taken in conjunction with a control device and an ignition system in the physical world to convert ignition operation. The method of Fig. 6 can be applied to ignition coils of all engine cylinders. The description of the first, second and third voltage pulse widths used in the method of Fig. 6 apply to voltage pulse widths that exist if the ignition system operates without deterioration.

[0061] At 602, method 600 determines engine speed and load. Engine speed may be determined via an engine position sensor output, and engine load may be determined via the output of an intake manifold pressure sensor or mass airflow sensor that detects airflow through the engine. After determining engine speed and load, method 600 proceeds to 604.

[0062] At 604, method 600 determines the cylinder spark timing and dwell period. In one example, method 600 indexes a table of empirically determined ignition angles and a table of ignition coil dwell times based on engine speed and load, as determined at 602, and measured battery voltage. The tables output an ignition angle relative to the top dead center compression stroke for the cylinder receiving the spark, as well as a dwell time based on the ignition coil design and engine operating conditions. For example, an ignition angle of -10 crankshaft degrees (e.g., 10 crankshaft degrees before the top dead center compression stroke of the cylinder receiving the spark) may be output from the table, and a dwell time of 2 milliseconds. After determining the ignition angle and dwell time, method 600 proceeds to 606.

[0063] At 606, method 600 determines the ignition coil primary shunt timing and ion signal integration timing. In one example, method 600 indexes a table that outputs an engine crankshaft angle at which ignition coil primary shunting should begin for a cylinder cycle. Further, method 600 indexes a second table that outputs an engine crankshaft angle at which ignition coil primary shunting should end for a cylinder cycle. Method 600 also indexes a table that outputs an engine crankshaft angle at which ion signal integration should begin for a cylinder cycle. Method 600 also indexes a second table that outputs an engine crankshaft angle at which ion signal integration should end for a cylinder cycle.

[0064] The window (e.g., crankshaft timing and duration for ion signal integration) for ion signal integration may be later than the spark angle determined at 604 so that misfire can be detected more precisely. For example, spark timing may be 30 crankshaft degrees before the top dead center compression stroke, and ion signal integration may be 10 crankshaft degrees before the top dead center compression stroke. The ion signal integration window may allow ion signal integration for 90 crankshaft degrees from the start timing of 10 crankshaft degrees before the top dead center compression stroke.

[0065] In the same way, the window (e.g., crankshaft timing and duration for ignition coil primary shunting) of the ignition coil primary shunting may be later than the ignition angle determined at 604. Further, the ignition coil primary shunting may begin at the same time as the ion signal integration. Alternatively, the ignition coil primary shunting may begin before or after the ion signal integration. The ion signal integration window and the ignition coil shunting window may therefore be at the timings specified in the Fig. 3 through 5. Method 600 proceeds to 608.

[0066] At 608, method 600 provides the requested spark timing, ion signal integration, and ignition primary coil shunt commands to the ignition system over a single conductor or wire. Spark timing for a cylinder is provided via a first voltage pulse on the wire during an engine cycle. The end of the first voltage pulse is provided at the crankshaft angle where the spark is desired, plus a delay time (for example, 45 microseconds). The beginning of the first voltage pulse is the dwell time determined at 604, plus the ignition angle of the desired spark and the delay time.For example, if the desired ignition timing is 30 crankshaft degrees before the compression stroke of top dead center and the dwell time is 2 milliseconds, the COPID signal transitions to a higher level of 2 milliseconds plus the first delay period and a second delay period (for example, 120 microseconds) before the engine reaches 30 crankshaft degrees before the compression stroke of top dead center for the cylinder receiving the spark. In this way, a dwell time and ignition angle or time can be commanded to the ignition circuit via a single voltage pulse.

[0067] Method 600 then evaluates the timing of the ion signal integration window and the timing of the ignition coil primary shunt window. If the ion signal integration window and the ignition coil primary shunt window have the same opening times (e.g., 301) and closing times (e.g., 303) as in Fig. 3, method 600 outputs two short-duration voltage pulses after the dwell voltage pulse is output. The first of the two voltage pulses (e.g., the second voltage pulse in the cylinder cycle) is output one cylinder cycle after the ignition dwell pulse (e.g., the first voltage pulse is output during the cylinder cycle). The first of the two voltage pulses, which indicates the beginning of the ignition primary coil shunt and / or ion signal integration timing, as shown in Fig. 3, is output to the ignition circuits. The second of the two voltage pulses, which represents the end of the ignition primary coil shunt and / or ion signal integration timing, as described in Fig. 3, is output to the ignition circuits. The two pulses are generated during the cylinder cycle after the spark timing dwell pulse, as shown in Fig. 3. Similar dwell and ignition primary coil shunt and / or ion signal integration timing voltage pulses may be output during subsequent cylinder cycles.

[0068] If the ion signal integration window and the ignition coil primary shunt window have the same opening times (for example, 405 and 406) and different closing times (for example, 407 and 409), as in Fig. 4, method 600 outputs three short duration voltage pulses after the dwell voltage pulse. The first of the three short duration voltage pulses (e.g., the second voltage pulse in the cylinder cycle) is output one cylinder cycle after the ignition dwell pulse (e.g., the first voltage pulse is output during the cylinder cycle). The first of the three short duration voltage pulses, which represents the beginning of the ignition primary coil shunt and / or ion signal integration timing, as shown in Fig. 4, is output to the ignition circuits. The second of the three short duration voltage pulses, which represents the end of an ignition primary coil shunt and / or ion signal integration timing, as described in Fig. 4, is output to the ignition circuits. The third of the three short duration voltage pulses, which represents the end of a second ignition primary coil shunt and / or ion signal integration timing, as described in Fig. 4, is output to the ignition circuits. The three pulses are generated during the cylinder cycle after the spark timing dwell pulse, as shown in Fig. 4, to provide a total of four voltage pulses during one cylinder cycle. Similar dwell and ignition primary coil shunt and / or ion signal integration timing voltage pulses may be output during subsequent cylinder cycles.

[0069] If the ion signal integration window and the ignition coil primary shunt window have different opening times (for example, 505 and 506) and different closing times (for example, 507 and 509), as in Fig. 5, method 600 outputs four short duration voltage pulses after the dwell voltage pulse. The first of the four short duration voltage pulses (e.g., the second voltage pulse in the cylinder cycle) is output one cylinder cycle after the ignition dwell pulse (e.g., the first voltage pulse is output during the cylinder cycle). The first of the four short duration voltage pulses, representing a first start of the ignition primary coil shunt and / or ion signal integration timing, as shown in Fig. 5, is output to the ignition circuits. The second of the four short duration voltage pulses, which represents the start of a second ignition primary coil shunt and / or ion signal integration timing, as described in Fig. 5, is output to the ignition circuits. The third of the four short duration voltage pulses, which represents the end of a first ignition primary coil shunt and / or ion signal integration timing, as described in Fig. 5, is output to the ignition circuits. The fourth of the four short duration voltage pulses, which represents the end of a second ignition primary coil shunt and / or ion signal integration timing, as described in Fig. 5, is output to the ignition circuits. The four short duration pulses are generated during the cylinder cycle following the spark timing dwell pulse, as shown in Fig. 5. Similar dwell and ignition primary coil shunt and / or ion signal integration timing voltage pulses may be output during subsequent cylinder cycles.

[0070] The dwell voltage pulse and the ignition primary coil shunt and / or ion signal integration timing voltage pulses are output from the controller to the ignition circuit via a single conductor or wire. A new voltage pulse train is provided at each cylinder cycle, and the pulse train reflects changes in engine operation. Method 600 proceeds to 610.

[0071] At 610, method 600 decodes the dwell voltage pulse and the ignition primary coil shunt and / or ion signal integration timing voltage pulses. In one example, the dwell voltage pulse is converted into a voltage pulse that is applied to the IGBT to charge and discharge the ignition coil. The ignition primary coil shunt and / or ion signal integration timing voltage pulses are converted into an ignition coil shunt voltage pulse that is applied to a shunt switch (e.g., 234 of the Fig. 2). Further, the ignition primary coil shunt and / or ion signal integration timing voltage pulses are converted into an ion signal integration voltage pulse, which is applied to an ion signal integrator. The ion signal integrator outputs a value of integrating an ion signal during the opening of an ion signal integrator window to the controller. Method 600 proceeds to the end after the pulse train provided to the controller has been decoded and the ignition system has been operated according to the pulse train.

[0072] In this way, the procedure of Fig. Six different numbers of short-duration voltage pulses are provided to specify the desired ion signal integration timing and ignition coil primary winding shunts. The short-duration voltage pulses are provided during a single cylinder cycle following a dwell pulse that specifies the ignition coil charging time and spark timing or angle.

[0073] The procedure of Fig. 6 therefore provides a method for providing a spark to an engine, comprising: receiving an input from one or more engine sensors to a controller and commanding, via the controller, the shunting, integration, charging, and discharging of an ignition coil during a cylinder cycle in response to the input, wherein the commanding is accomplished via a single conductor providing electrical connection between the controller and an ignition coil driver circuit.

[0074] The method includes commanding the charging and discharging of the ignition coil via a dwell pulse across the single conductor. The method includes shunting providing a low-resistance electrical path between a first side of a primary coil of an ignition coil and a second side of the primary ignition coil.

[0075] The method includes shunting being performed during a crankshaft interval of the engine in which engine knock is expected (e.g., from TDC to 90 crankshaft degrees after TDC of the cylinder receiving spark). The method includes one or more engine sensors comprising an engine crankshaft position sensor. The method includes the ignition coil driver circuit comprising a pulse decoder circuit. The method includes commanding being provided via one or more voltage pulses across the single conductor. The method includes shunting (e.g., providing a low resistance current path between two sides of a primary ignition coil) comprising closing a switch between a first side of a primary coil of an ignition coil and a second side of the primary ignition coil.

[0076] The procedure of Fig. 6 also provides a method for providing a spark to an engine, comprising receiving an input from one or more engine sensors to a controller and commanding, via the controller, the shunting, integration, charging, and discharging of an ignition coil during a cylinder cycle in response to the input, wherein the commanding is accomplished via a single conductor providing electrical connection between the controller and an ignition coil driver circuit and three or more voltage pulses.

[0077] The method comprises commanding, via the controller, an ion signal integration timing, wherein the ion signal integration timing is shortened so as not to integrate a fully late combustion ion waveform during the cylinder cycle, wherein a third voltage pulse of the at least three or more voltage pulses is a voltage pulse for starting or ending ignition coil shunting or a voltage pulse for starting or ending ion signal integration, and wherein a fourth voltage pulse of the at least three or more voltage pulses is a voltage pulse for starting ignition coil shunting or ion signal integration.The method includes the shunt and ion signal integration timing being later than a pulse representing ignition timing dwell time, wherein a third voltage pulse of the at least three or more voltage pulses is a voltage pulse for beginning ignition coil shunting or ion signal integration. The method includes a first voltage pulse of the three or more voltage pulses being an ignition timing dwell time pulse, and a third voltage pulse of the three or more voltage pulses being a pulse for ending ignition coil shunting or ion signal integration.

[0078] The method also includes a second voltage pulse of the three or more voltage pulses being a pulse for starting ignition coil shunting, ion signal integration, or both ignition coil shunting and ion signal integration, a third voltage pulse of the three or more voltage pulses being a pulse for ending ignition coil shunting, ion signal integration, or ending both ignition coil shunting and ion signal integration, a fourth voltage pulse of the three or more voltage pulses being a pulse for ending ignition coil shunting and ending ion signal integration, or ending both ignition coil shunting and ion signal integration, a fifth voltage pulse of the three or more voltage pulses being a pulse for ending ignition coil shunting or ion signal integration.The method also includes the three or more voltage pulses comprising a pulse for an ignition dwell time, a pulse shorter than the ignition dwell time pulse for starting primary ignition coil shunting, a pulse shorter than the ignition dwell time pulse for starting ion signal integration, a pulse shorter than the ignition dwell time pulse for ending primary ignition coil shunting, and a pulse shorter than the ignition dwell time pulse for ending ion signal integration.

[0079] Now with reference to Fig. 7 shows representations of ignition system commands and ion signal integration for normal and late combustion for one cylinder cycle. The representations show an encoded COPID signal 702 for commanding and providing spark timing and ion signal integration. The COPID 702 is a coil-on-spark plug control signal for ignition timing and ion signal integration timing for an engine cylinder during one cylinder cycle. The spark timing and ion signal integration timing are encoded in three voltage pulses. The COPID signal 702 is provided by the controller to the ignition circuits. Fig. The signals shown in Figure 7 can be generated by the system of Fig. 1 and Fig. 2 in accordance with the procedure of Fig. 6 are provided. Fig. Figure 7 shows a contrast in ion signals for normal and late combustion. The timing of the voltage pulses for integrating the ion signal is based on crankshaft angle times for expected combustion rates of the air-fuel mixture in the cylinder based on engine speed and engine load.

[0080] The first representation at the top of the Fig. Figure 7 is a plot of COPID versus time. The vertical axis represents the COPID voltage, and the horizontal axis represents time. The COPID voltage increases in the direction of the vertical axis arrow. Time decreases from the left side of the Fig. 7 to the right side of the Fig. 7 to.

[0081] The second view from the top of the Fig. Figure 7 is a plot of an ion signal for normal combustion versus time. The vertical axis represents the ion signal voltage for normal combustion, and the horizontal axis represents time. The ion signal voltage for normal combustion increases in the direction of the vertical axis arrow. Time decreases from the left side of the Fig. 7 to the right side of the Fig. 7 to.

[0082] The third representation from the top of the Fig. Figure 7 is a plot of current consumption on the COPID signal, showing the integrated ion signal for normal combustion versus time. The vertical axis represents the current consumption on the COPID and shows two non-zero values ​​during the dwell time. The horizontal axis represents time, and time increases from the left to the right of the plot. The integrated ion signal for normal combustion is plotted from the time from the beginning of the dwell time (i.e., the rising edge of the dwell time voltage pulse) to the current switching from high to low.

[0083] The fourth representation from the top of the Fig. Figure 7 is a plot of an ion signal for late combustion versus time. The vertical axis represents the ion signal voltage for normal combustion, and the horizontal axis represents time. The ion signal voltage for late combustion increases in the direction of the vertical axis arrow. Time decreases from the left side of the Fig. 7 to the right side of the Fig. 7 to.

[0084] The fifth representation from the top of the Fig. Figure 7 is a plot of power consumption on the COPID signal, showing the integrated ion signal for late combustion versus time. The vertical axis represents the power consumption on the COPID signal and shows two non-zero values ​​during the residence time. The horizontal axis represents time. Time decreases from the left side of the Fig. 7 to the right side of the Fig. 7. The integrated ion signal for late combustion is represented by the time from the beginning of the residence time to the current switching from the high to the low level.

[0085] At time T30, the COPID signal is at a lower level, and ignition timing control signals for a previous cylinder cycle have ended. The ion signals for normal and late combustion are zero (e.g., the ion signal level of the horizontal axis), as are the current consumption values ​​on COPID for normal and late combustion.

[0086] At time T31, the controller outputs a rising edge of a dwell voltage pulse for the cylinder in which spark is commanded. The dwell time between time T31 and time T32 defines the amount of energy stored in an ignition coil. The ion signals for normal and late combustion are zero (e.g., the ion signal level of the horizontal axis). The current consumption values ​​on COPID both go high.

[0087] At some time before T32, the current consumption values ​​on COPID both go to their lower levels when switch 211 opens. The time from the beginning of the dwell time T31 to this switching point indicates the integrated ion signal value for the preceding combustion event.

[0088] At time T32, the controller outputs a falling edge of the voltage pulse, ending the dwell period and beginning the coil discharge that generates the spark in the cylinder. The ion signals for normal and late combustion are zero (e.g., the ion signal level of the horizontal axis), as are the COPID current consumption values ​​for normal and late combustion. Stored integration values ​​from the previous combustion event are reset to zero.

[0089] At time T33, the controller outputs a rising edge of a voltage pulse, indicating that the start of the ion signal integration period will follow shortly. The normal and late combustion ion signals may be non-zero (for example, the ion signal level is above the horizontal axis), but no signal content is integrated. The COPID current consumption values ​​for normal and late combustion remain at zero. In this example, the first voltage pulse following the dwell voltage pulse in the cylinder cycle is output at a time shortly after the normal combustion ion signal and the late combustion ion signal begin to rise.

[0090] At time T34, the controller outputs a falling edge of a voltage pulse, indicating the beginning of the ion signal integration period. The ion signals for normal and late combustion continue to increase, and ion signal integration begins.

[0091] Between time T34 and time T35, the normal combustion ion signal increases and decreases twice, however, not all ion signals follow the trajectory shown. The first peak occurs soon after time T34, and a second peak occurs before time T35. The late combustion ion signal increases once and decreases once between time T34 and time T35. Furthermore, the magnitude of the late combustion ion signal is reduced due to late combustion. The engine crankshaft angle window is adjusted to incorporate a crankshaft range in which a predetermined portion (e.g., greater than 75%) of the normal combustion ion signal is expected to occur. The engine crankshaft angle window begins and ends before a predetermined portion (e.g., less than 75%) of a late combustion ion signal is expected to occur.The integrator therefore integrates a larger portion of a normal combustion ion signal compared to a portion of the late combustion ion signal.

[0092] At time T35, the controller outputs a rising edge of a voltage pulse, indicating that the end of the ion signal integration period is imminent. In this example, the normal combustion ion signal continues to decrease, and the late combustion ion signal also decreases; however, this may not be the case in other examples.

[0093] At time T36, the controller outputs a falling edge of a voltage pulse, indicating the end of the ion signal integration period. The falling edge of the third voltage pulse occurs before the end of the late combustion ion signal content. This interrupts the integration of the late combustion ion signal, so that the integrated late combustion ion signal is lower than the normal combustion ion signal.

[0094] Between time T36 and time T37, the late combustion ion signal increases, but since the ion signal integration period has ended, the integrated late combustion ion signal does not increase. The timing of the voltage pulses at times T33 and T35 therefore allows the normal combustion ion signal to integrate both ion signal peaks, while only allowing integration of one peak of the late combustion ion signal in this example. The lower integrated late combustion ion signal can be a basis for determining undesired combustion.

[0095] At time T37, the cylinder cycle is over, and a new dwell pulse is issued for a subsequent cylinder cycle. COPID current consumption goes to a higher level. At some time before the end of dwell time T38, COPID current consumption switches to the lower level, with the switchover point for the late combustion cycle occurring earlier. In this way, the integrator values ​​are fed back to the controller. At time T38, the dwell time ends, spark occurs, and the integrators are reset to zero before integration begins for this subsequent cylinder cycle.

[0096] The ion signal integration period between T34 and T36 can therefore be used to distinguish normal combustion from late combustion. In particular, if the integrated ion signal is less than a threshold but greater than a misfire case, it can be determined that late combustion is occurring. The timing between T34 and T36 can be shortened to a predetermined engine crankshaft angle time to improve detection of late combustion. Likewise, the timing between T34 and T36 can be increased to integrate a larger portion of an ion signal for late combustion.

[0097] As is obvious to an average person skilled in the art, the Fig.6 may represent one or more processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, and the like. Therefore, various illustrated steps or functions may be performed in the order illustrated, in parallel, or in some cases omitted. Likewise, the processing order is not required to achieve the objects, features, and advantages described herein, but is provided for convenience of illustration and description. The methods and sequences described herein may be provided via executable instructions stored in non-transitory memory of a controller in the system or systems described herein.Although not explicitly shown, it will be apparent to one of ordinary skill in the art that one or more of the steps or functions shown may be performed repeatedly depending on the particular strategy used.

[0098] This concludes the description. A reading of the description by one skilled in the art would reveal many changes and modifications without departing from the spirit and scope of the description. For example, I3, I4, I5, V6, V8, V10, and V12 engines powered by natural gas, gasoline, or alternative fuel configurations could advantageously utilize the present description.

Claims

[1] A method for providing a spark to a machine (10), comprising: Receiving an input from one or more machine sensors to a control device (12), and Commanding, via the control device (12), the shunting, integrating, charging, and discharging of an ignition coil (240) during a cylinder cycle in response to the input, wherein the commanding is implemented via a single conductor providing electrical connection between the control device (12) and an ignition coil driver circuit, and the shunt provides a low resistance electrical path between a first side of a primary coil of an ignition coil (240) and a second side of the primary ignition coil, characterized by , that the shunting is carried out during a crankshaft interval of the engine (10) in which engine knocking is expected. [2] The method of claim 1, wherein charging and discharging of the ignition coil (240) are commanded via a dwell pulse over the single conductor. [3] The method of claim 1 or 2, wherein one or more engine sensors comprise an engine crankshaft position sensor (118). [4] A method according to any one of claims 1 to 3, wherein the ignition coil driver circuit comprises a pulse decoder circuit (204). [5] A method according to any one of claims 1 to 4, wherein the commanding is provided via one or more voltage pulses across the single conductor. [6] The method of any one of claims 1 to 5, wherein shunting comprises closing a switch between a first side of a primary coil of an ignition coil (240) and a second side of the primary ignition coil. [7] A method for providing a spark to a machine (10), comprising: Receiving an input from one or more machine sensors to a control device (12), and Commanding, via the control device (12), the shunting, integrating, charging and discharging of an ignition coil during a cylinder cycle in response to the input, wherein the commanding is implemented via a single conductor providing electrical connection between the control device (12) and an ignition coil driver circuit and three or more voltage pulses, characterized by , that further comprising commanding via the controller (12) an ion signal integration timing, wherein the ion signal integration timing is shortened so as not to integrate an entire late combustion ion waveform during the cylinder cycle, wherein a third voltage pulse of the at least three or more voltage pulses is a voltage pulse for starting or ending ignition coil shunting or a voltage pulse for starting or ending ion signal integration, and wherein a fourth voltage pulse of the at least three or more voltage pulses is a voltage pulse for starting ignition coil shunting or ion signal integration. [8] The method of claim 7, wherein the shunt and ion signal integration timing occurs later in time than a pulse representing ignition coil dwell time, wherein a third voltage pulse of the at least three or more voltage pulses is a voltage pulse for initiating ignition coil shunting or ion signal integration. [9] A method according to any one of claims 7 or 8, wherein a first voltage pulse of the three or more voltage pulses is an ignition timing control dwell pulse, and wherein a third voltage pulse of the three or more voltage pulses is a pulse for terminating ignition coil shunting or ion signal integration. [10] The method of claim 9, wherein a second voltage pulse of the three or more voltage pulses is a pulse for starting ignition coil shunting, ion signal integration, or both ignition coil shunting and ion signal integration, wherein a third voltage pulse of the three or more voltage pulses is a pulse for ending ignition coil shunting, ion signal integration, or ending both ignition coil shunting and ion signal integration, wherein a fourth voltage pulse of the three or more voltage pulses is a pulse for ending ignition coil shunting and ending ion signal integration, or ending both ignition coil shunting and ion signal integration, wherein a fifth voltage pulse of the three or more voltage pulses is a pulse for ending ignition coil shunting or ion signal integration. [11] A method according to any one of claims 7 to 10, wherein the three or more voltage pulses comprise a pulse for an ignition dwell time, a pulse shorter than the ignition dwell time pulse for starting primary ignition coil shunting, a pulse shorter than the ignition dwell time pulse for starting ion signal integration, a pulse shorter than the ignition dwell time pulse for ending primary ignition coil shunting, and a pulse shorter than the ignition dwell time pulse for ending ion signal integration.

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