METHOD AND SYSTEM FOR OPERATING INTERNAL COMBUSTION ENGINES

Abstract

Internal combustion engine operating procedures, including: Receiving a signal to a controller (12); Setting coefficients (b0, b1, ... b N ) of a filter with a finite impulse response in response to an internal combustion engine intake ratio (i r ); Filtering the signal through the finite impulse response filter; Filtering the output of the finite impulse response filter via a low-pass filter in response to a change in the combustion engine intake ratio (i r ); Non-filtering of the finite impulse response output of the low-pass filter in response to a lack of change in the combustion engine intake ratio; and Setting one or more actuators in response to the filtered signal.

Description

Area

[0001] This description relates to an internal combustion engine operating method and an internal combustion engine system, in particular for improving the operation of an internal combustion engine that includes cylinders which can be selectively switched on and off to save fuel while meeting an internal combustion engine torque demand. The system and the methods can be applied to an internal combustion engine that deactivates internal combustion engine cylinders by shutting off the intake and exhaust valves of the deactivated cylinders. Background and brief description

[0002] An internal combustion engine control system can sense the intake manifold pressure of the internal combustion engine to determine engine operating parameters, which form the basis for adjusting internal combustion engine actuators. For example, the intake manifold pressure can be queried to determine the intake manifold absolute pressure (MAP). The intake manifold pressure, along with the engine speed, can be converted into the amount of air flowing through the engine using the ideal gas law. Once the airflow is known, the desired amount of fuel, providing a desired air-fuel ratio, can be determined by dividing the airflow rate by the desired air-fuel ratio.However, the intake manifold pressure of an internal combustion engine can contain frequencies that may cause it to exhibit a standard deviation larger than desired. If the engine's fuel quantity is adjusted in response to the raw (e.g., unfiltered) intake manifold pressure, measured at a slow rate and with fixed crankshaft intervals, the engine's air-fuel ratio may vary more than intended.

[0003] For example, German patent application DE 32 00 547 A1 describes an injection system for an internal combustion engine in which the injected fuel quantity is regulated depending on the intake manifold pressure. A low-pass filter suppresses pulsating signal components of the intake manifold pressure, and another low-pass filter compensates for response delays. Furthermore, German patent application WO 2018 / 039 078 A1 describes an internal combustion engine in which a smoothing of the torque curve is achieved by intervening in the combustion conditions. Individual cylinders are deactivated using a cylinder deactivation control system, and a torque signal is filtered, with the filter coefficients depending on the intake manifold ratio of the internal combustion engine.

[0004] One way to reduce the air-fuel variation of the internal combustion engine is to apply a first-order low-pass filter to a MAP signal and query the MAP signal at a rate that is an integer multiple of the internal combustion engine's ignition frequency. The filtered MAP can then be used to determine the amount of fuel to inject into the internal combustion engine.However, if the internal combustion engine is capable of switching individual cylinders off and on again, so that the actual total number of active cylinders changes from combustion engine cycle to combustion engine cycle, processing the MAP sensor signal via a first-order low-pass filter and a constant polling frequency cannot provide a filtered MAP sensor signal suitable for controlling fuel injection of the internal combustion engine, since frequencies within the MAP sensor signal change dynamically while poles of the first-order filter remain constant.

[0005] The inventors of the present invention recognized the aforementioned problems and developed an internal combustion engine operating method according to claim 1 and claim 8, as well as an internal combustion engine system according to claim 9. Preferred embodiments of the invention are the subject of the dependent claims.

[0006] The proposed internal combustion engine operating procedure thus comprises: receiving a signal to a controller; adjusting coefficients of a finite impulse response filter in response to an internal combustion engine intake ratio (e.g., the actual total number of active cylinders in a cylinder cycle (cylinders burning air and fuel) divided by the actual total number of internal combustion engine cylinders); filtering the signal through the finite impulse response filter; and adjusting one or more actuators in response to the filtered signal.

[0007] By adjusting the coefficients of a finite impulse response filter or an infinite impulse response filter in response to the internal combustion engine intake ratio, it is possible to achieve the technical result of providing a filtered internal combustion engine signal exhibiting a desired dynamic response with a desired standard deviation, even when the engine is operating with an intake ratio less than one. When an internal combustion engine signal is filtered as described, the filtered signal can have a desired standard deviation, enabling precise control of the engine's air-fuel ratio. Furthermore, other internal combustion engine actuators, such as camshafts and intake manifolds, can be controlled more accurately when the engine intake ratio changes or is a fractional value.The finite impulse response filter can be implemented via instructions in a controller, so that the modification of filter coefficients can be synchronized with cylinder mode changes.

[0008] The present description can offer several advantages. Specifically, the approach can improve the air-fuel control of the internal combustion engine. Furthermore, the approach can be applied to a wide variety of different internal combustion engines with varying cylinder configurations. Even further, the approach can eliminate or reduce signal strength at frequencies that tend to increase the signal's standard deviation, thus enabling the trouble-free control of actuators configured to respond to the signal while providing the desired dynamic response. Brief description of the drawings

[0009] The advantages described here become more fully apparent from reading an example of an embodiment, referred to here as the detailed description, either on its own or with reference to the drawings, in which the following applies: Fig. Figure 1 is a schematic representation of an internal combustion engine; Fig. 2A is a schematic representation of an eight-cylinder engine with two cylinder banks; Fig. 2B is a schematic representation of a four-cylinder engine with a single cylinder bank; Fig. Figure 3 shows an internal combustion engine signal that has been filtered according to the state of the art and the present description; Fig. Figure 4 shows a flowchart of a procedure for filtering internal combustion engine signals; and Fig. Figure 5 is a graphical representation of a finite impulse response filter. Detailed description

[0010] The present description concerns the filtering of signals from an internal combustion engine and the control of the internal combustion engine in response to the filtered signals. An internal combustion engine containing cylinders that can be selectively deactivated is described in... Fig. 1 shown. Fig. 2A and Fig. 2B shows exemplary configurations for the in Fig. 1 described internal combustion engine. Fig. Figure 3 shows an exemplary sequence in which the internal combustion engine intake ratio changes and two different types of filters are applied to signals output by an internal combustion engine sensor. An exemplary method for processing a signal and controlling an internal combustion engine in response to the processed signal is shown in Fig. 4 shown.

[0011] With reference to Fig. 1 is an internal combustion engine 10, comprising a plurality of cylinders, one of which is in Fig. As shown in Figure 1, the internal combustion engine is controlled by the electronic combustion engine control unit 12. The internal combustion engine 10 includes a combustion chamber 30 and cylinder walls 32 with a piston 36 positioned therein and connected to a crankshaft 40.

[0012] The combustion chamber 30 is shown communicating with an intake manifold 44 and an exhaust manifold 48 via an intake valve 52 and an exhaust valve 54, respectively. The exhaust valve can be operated by a variable exhaust valve operator 53, which can be actuated mechanically, electrically, hydraulically, or by a combination thereof. For example, the exhaust valve actuators can be of the type described in US 2014 / 0303873A1, US 6321704B1, US 6273039B1, and US 7458345B2, which are hereby incorporated in full for all purposes. The exhaust valve 54 can be held closed by the variable exhaust valve operator 53 throughout an entire combustion engine cycle. Furthermore, the exhaust valve operator can open the exhaust valves 54 synchronously or asynchronously with the crankshaft 40. The position of the exhaust valve 54 can be determined by an exhaust valve position sensor 57.The intake valve 52 is opened and closed by the intake valve operator 51, which can be of the same type as the exhaust valve operator 53. The position of the intake valve 52 can be determined by the intake valve position sensor 59. The intake valve 52 can be held closed for an entire combustion engine cycle by means of a variable intake valve actuator 51 to deactivate a combustion engine cylinder (e.g., no combustion occurs in the cylinder for at least one combustion engine cycle when a cylinder is deactivated). In one example, the intake valve 52 and the exhaust valve 54 are held closed, and no fuel is injected into cylinder 30 when cylinder 30 is deactivated. Other combustion engine cylinders may be engaged while cylinder 30 is deactivated.

[0013] The fuel injection device 66 is positioned, as shown, to inject fuel directly into the cylinder 30, a process known to those skilled in the art as direct injection. Alternatively, fuel can be injected into an intake port, a process known to those skilled in the art as one-nozzle-per-intake injection. The fuel injection device 66 dispenses liquid fuel proportionally to the pulse width of the signal from the control unit 12. Fuel is supplied to the fuel injection device 66 by a fuel system 175. Additionally, the intake manifold 44 communicates, as shown, with an optional electronic throttle 62 (e.g., a butterfly valve), which sets the position of the throttle valve 64 to control the airflow from an air filter 43 and an air inlet 42 to the intake manifold 44. The throttle 62 regulates the airflow from the air filter 43 in the combustion engine air inlet 42 to the intake manifold 44.In one example, a two-stage high-pressure fuel system can be used to generate higher fuel pressures. In some examples, the throttle 62 and the throttle valve 64 can be positioned between the intake valve 52 and the intake manifold 44 such that the throttle 62 acts as an intake port throttle.

[0014] The distributorless ignition system 88 provides a spark to the combustion chamber 30 via a spark plug 92 in response to the control unit 12. According to the diagram, a wideband lambda sensor (UEGO sensor) 126 is coupled to the exhaust manifold 48 upstream of a catalytic converter 70. Alternatively, the UEGO sensor 126 can be replaced by a binary lambda sensor.

[0015] In one example, catalyst 70 can contain multiple catalyst honeycomb bodies. In another example, multiple emission control devices, each with several components, can be used. In one example, catalyst 70 can be a three-way catalyst.

[0016] Control 12 is in Fig. Figure 1 is shown as a conventional microcomputer comprising the following: microprocessor unit 102, input / output ports 104, read-only memory 106 (e.g., non-volatile memory), random access memory 108, keep-alive memory 110, and a conventional data bus. According to the illustration, the controller 12 receives various signals from sensors coupled to the internal combustion engine 10, in addition to the signals discussed previously. These signals include: the internal combustion engine coolant temperature (ECT) from the temperature sensor 112, which is coupled to the cooling sleeve 114; a position sensor 134, which is coupled to an accelerator pedal 130 to detect the force applied by the human driver 132; and a measurement of the internal combustion engine manifold pressure (MAP) from the pressure sensor 122, which is coupled to the intake manifold 44. an internal combustion engine position sensor from a Hall effect sensor 118, which detects the position of the crankshaft 40;a measurement of the air mass entering the combustion engine from sensor 120; a brake pedal position from brake pedal position sensor 154 when the human driver 132 operates a brake pedal 150;a turbocharger wastegate position sensor 156 (if present), alternatively the sensor 156 can be an exhaust pressure sensor positioned in an exhaust manifold, and a measurement of the throttle position from the sensor 58. Atmospheric pressure can also be acquired for processing by the controller 12 (sensor not shown). In a preferred aspect of the present description, the internal combustion engine position sensor 118 generates a predetermined number of evenly spaced pulses at each revolution of the crankshaft, from which the internal combustion engine speed (rpm) can be determined. A user interface 155, which can be referred to as a display or control panel, allows vehicle occupants to query the vehicle mode (e.g., economy / standard) and to receive queries or diagnostic information from the controller 12.

[0017] In some examples, the combustion engine may be coupled to an electric motor / battery system in a hybrid vehicle. Furthermore, other combustion engine configurations may be used in some examples, for example, a diesel engine.

[0018] During operation, each cylinder in the internal combustion engine 10 typically undergoes 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 toward the bottom of the cylinder, thus increasing the volume within the combustion chamber 30. The position at which the piston 36 is near the bottom of the cylinder and at the end of its stroke (e.g., when the combustion chamber 30 has reached its maximum 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, thus compressing the air in the combustion chamber 30.The point at which the piston 36 is closest to the cylinder head at the end of its stroke (e.g., when the combustion chamber 30 has its smallest volume) is typically referred to by those skilled in the art as top dead center (TDC). In a process hereinafter referred to as injection, fuel is introduced into the combustion chamber. In a process hereinafter referred to as ignition, the injected fuel is ignited by known ignition means, such as the spark plug 92, resulting in combustion. During the power stroke, the expanding gases push the piston 36 back to bottom dead center (BDC). The crankshaft 40 converts piston movements into a torque of the crankshaft. Finally, during the exhaust stroke, the exhaust valve 54 opens to release the burnt air-fuel mixture to the exhaust manifold 48, and the piston returns to TDC.It should be noted that the above is merely an example and that the timing of the opening and / or closing of the intake and exhaust valves may vary, for example to provide positive or negative valve overlap, late closing of the intake valve, or various other examples.

[0019] With reference to Fig. Figure 2A now shows an exemplary multi-cylinder internal combustion engine, which includes two cylinder banks. The internal combustion engine includes cylinders and associated components, as shown in Fig. The internal combustion engine described in Figure 10 comprises eight cylinders 30. Each of the eight cylinders is numbered, and the cylinder numbers are included within the cylinders. The fuel injection devices 66 selectively supply fuel to each of the cylinders that are switched on (e.g., burning fuel during an internal combustion engine cycle). Cylinders 1-8 can be selectively deactivated to improve the fuel efficiency of the internal combustion engine when less than the engine's full torque capacity is required. For example, cylinders 2, 3, 5, and 8 can be deactivated during an internal combustion engine cycle (e.g., two revolutions for a four-stroke engine) and can remain deactivated for a variety of internal combustion engine cycles while the internal combustion engine speed and load are constant or vary slightly.During another combustion engine cycle, a second fixed pattern of cylinders 1, 4, 6, and 7 can be deactivated. Furthermore, other patterns of cylinders can be selectively deactivated based on vehicle operating conditions (e.g., combustion engine speed and load). Additionally, combustion engine cylinders can be deactivated in such a way that a fixed pattern of cylinders is not deactivated over a multitude of combustion engine cycles. Instead, the cylinders that are deactivated can change from one combustion engine cycle to the next.

[0020] Each cylinder bank 202 and 204 includes variable valve actuators 53 for switching the intake valves on and off. The variable valve actuators can be operated via camshafts 254. Intake valves are held in a closed position when switched off. Furthermore, each cylinder includes variable exhaust valve actuators 53 for selectively switching the exhaust valves on and off. An internal combustion engine cylinder can be switched off by stopping the fuel flow to the cylinder and holding its intake and exhaust valves in a closed state for an entire internal combustion engine cycle. An internal combustion engine cylinder can be switched on by beginning to open and close the exhaust and intake valves during an internal combustion engine cycle while fuel is supplied to the cylinder. The internal combustion engine 10 includes a first cylinder bank 204, which contains four cylinders 1, 2, 3, and 4.The internal combustion engine 10 also includes a second cylinder bank 202, which contains four cylinders 5, 6, 7 and 8. The cylinders of each bank can be active or deactivated during a cycle of the internal combustion engine.

[0021] Now, with reference to Fig. Figure 2B now shows an exemplary internal combustion engine with multiple cylinders, including one cylinder bank. The internal combustion engine includes cylinders and associated components, as shown in Fig. 1 described internal combustion engine. The internal combustion engine 10 comprises four cylinders 210. Each of the four cylinders is numbered, and the cylinder numbers are included in the cylinders. The fuel injection devices 66 selectively supply fuel to each of the cylinders that are switched on (e.g., burning fuel during a cycle of the internal combustion engine, with the intake and exhaust valves opening and closing during a cycle of the active cylinder). Cylinders 1-4 can be selectively switched off (e.g., not burning fuel during a cycle of the internal combustion engine, with the intake and exhaust valves held in a closed state for an entire cycle of the switched-off cylinder) to improve the internal combustion engine fuel efficiency when less than the full torque capacity of the internal combustion engine is required. For example, cylinders 2 and 3 (e.g.,A fixed pattern of deactivated cylinders can be deactivated during a multitude of engine cycles (e.g., two revolutions for a four-stroke engine). During another engine cycle, a second fixed pattern of cylinders 1 and 4 can be deactivated over a multitude of engine cycles. Furthermore, other patterns of cylinders can be selectively deactivated based on vehicle operating conditions. Additionally, engine cylinders can be deactivated in such a way that a fixed pattern of cylinders is not deactivated over a multitude of engine cycles. Instead, the deactivated cylinders can change from one engine cycle to the next. In this way, the deactivated engine cylinders can rotate or change from one engine cycle to the next.

[0022] The internal combustion engine 10 includes a single cylinder bank 250, which contains four cylinders 1-4. The cylinders of each bank can be active or deactivated during an internal combustion engine cycle. The cylinder bank 250 includes variable intake valve actuators 51 for operating the intake valves. Furthermore, each cylinder includes variable exhaust valve actuators 53 for selectively turning the exhaust valves on and off. The variable valve actuators can be operated via camshafts 254. An internal combustion engine cylinder can be deactivated by stopping the fuel flow to the cylinder and keeping its intake and exhaust valves closed for an entire internal combustion engine cycle. The internal combustion engine cylinder can be turned on by beginning to open and close the exhaust and intake valves during an internal combustion engine cycle while fuel is supplied to the cylinder.

[0023] The system made of Fig. 1-2B provides an internal combustion engine system comprising: an internal combustion engine including one or more cylinder valve shut-off mechanisms; a sensor coupled to the internal combustion engine; an actuator coupled to the internal combustion engine; a controller including executable instructions stored in non-volatile memory to selectively shut off one or more internal combustion engine cylinders and to set coefficients of a finite impulse response filter applied to a signal generated via the sensor; instructions to apply a second filter to the output of the finite impulse response filter in response to a change in the internal combustion engine intake ratio; and instructions to apply the actuator in response to the output of the finite impulse response filter and the output of the second filter.The internal combustion engine system further includes additional executable instructions to set the coefficients via values ​​stored in a table or matrix in the control unit's memory. The internal combustion engine system includes the actuator being a fuel injection device. The internal combustion engine system includes the actuator being an internal combustion engine throttle. The internal combustion engine system includes the second filter being a low-pass filter. The internal combustion engine system includes the second filter consisting of instructions stored in the control unit's memory.

[0024] Now, with reference to Fig. Figure 3 shows a prophetic sequence demonstrating state-of-the-art signal filtering and signal filtering according to the present description. The waveforms are temporally aligned and occur simultaneously. The vertical lines at t0-t4 represent times of interest during the sequence. The signal filtering shown in the present sequence can be implemented using the method described in Fig. 4 together with the system from the Fig. 1-2B will be provided.

[0025] The first course from the top into Fig. Figure 3 shows the combustion engine intake ratio over time. The vertical axis represents the combustion engine intake ratio, which increases in the direction of the arrow on the vertical axis. The horizontal axis represents time, and time increases from the left side of the figure to the right side.

[0026] The second course from the top in Fig. Figure 3 shows the curve of pure (e.g., unfiltered) intake manifold pressure of the internal combustion engine over time. The vertical axis represents the intake manifold pressure of the internal combustion engine, and this pressure increases in the direction of the arrow on the vertical axis. The horizontal axis represents time, and time increases from the left side of the figure to the right side.

[0027] The third course from the top in Fig. Figure 3 shows the intake manifold pressure of the internal combustion engine as a function of time according to a prior art method (e.g., a first-order low-pass filter). In other words, the third graph shows the output of a prior art filtering method that filters the pure signal shown in the second graph. The vertical axis represents the filtered intake manifold pressure of the internal combustion engine, and this pressure increases in the direction of the arrow on the vertical axis. The horizontal axis represents time, and time increases from the left side of the figure to the right side.

[0028] The fourth course from the top in Fig. Figure 3 shows the intake manifold pressure of the internal combustion engine as described above (e.g., a finite impulse response (FIR) filter with adjustable coefficients) versus time. In other words, the fourth graph shows the output of a filter as described above, which filters the pure signal shown in the second graph. The vertical axis represents the filtered intake manifold pressure of the internal combustion engine, and the filtered intake manifold pressure of the internal combustion engine increases in the direction of the arrow on the vertical axis. The horizontal axis represents time, and time increases from the left side of the figure to the right side of the figure.

[0029] The intake manifold pressure scaling of the internal combustion engine is equivalent for the second, third, and fourth curves. Therefore, the scaling and range of the vertical axes of the second, third, and fourth curves are equivalent.

[0030] At time t0, the combustion engine intake ratio is a value of one, indicating that all combustion engine cylinders are active. The combustion engine is burning air and fuel in all cylinders (not shown). The signal for the pure intake manifold pressure of the combustion engine is at a lower value, and both the prior art filtration method and the filtration method described here are at lower values.

[0031] Between time t0 and time t1, the internal combustion engine is operating with all its cylinders active (e.g., burning air and fuel). The raw intake manifold pressure of the internal combustion engine exhibits a small standard deviation. The output of the prior art filtering method smooths the raw intake manifold pressure signal of the internal combustion engine and provides a filtered output with an even smaller standard deviation. The output of the filter according to the present description similarly provides a smoothed intake manifold pressure of the internal combustion engine.

[0032] At time t1, the combustion engine intake ratio is reduced in response to the combustion engine operating conditions (not shown). The pure intake manifold pressure of the combustion engine increases when the intake ratio decreases, allowing the combustion engine to deliver a nearly constant amount of torque. The intake manifold pressure of the combustion engine can be increased by opening the combustion engine throttles (not shown). The output size of the prior art filtration method increases in response to the increase in the pure intake manifold pressure of the combustion engine. The output size of the filter according to the present description also increases in response to the increase in the pure intake manifold pressure of the combustion engine. Coefficients for the filter according to the present description are adjusted in response to changes in the combustion engine intake ratio.

[0033] Between time t1 and time t2, the internal combustion engine operates, with fewer than all of its cylinders active (e.g., burning air and fuel). The standard deviation of the pure intake manifold pressure of the internal combustion engine has increased significantly. The output of the prior art filtration method exhibits nearly the same standard deviation as the pure intake manifold pressure signal of the internal combustion engine. The size of the filter output in the prior art varies such that the control of the internal combustion engine's air-fuel ratio based on its output can vary more than desired. The filter output size according to the present description provides a smoothed intake manifold pressure of the internal combustion engine, which allows for more precise control of the internal combustion engine's air-fuel ratio.

[0034] At time t2, the combustion engine intake ratio is reduced again in response to the combustion engine operating conditions (not shown). The pure intake manifold pressure of the combustion engine is further increased as the intake ratio decreases, allowing the combustion engine to deliver a nearly constant amount of torque. The output size of the prior art filtration method increases in response to the increase in the pure intake manifold pressure of the combustion engine. The output size of the filter according to the present description also increases in response to the increase in the pure intake manifold pressure of the combustion engine. Coefficients for the filter according to the present description are adjusted a second time in response to the change in the combustion engine intake ratio.

[0035] Between time t2 and time t3, the internal combustion engine is operating, although fewer than all of its cylinders are active (e.g., burning air and fuel). The standard deviation of the pure intake manifold pressure of the internal combustion engine remains large. The standard deviation of the output of the prior art filtration method also remains large. However, the filter output according to the present description provides a smoothed intake manifold pressure of the internal combustion engine, which allows for more precise control of the air-fuel ratio of the internal combustion engine. In other words, the standard deviation of the intake manifold pressure output from the filter according to the present description is smaller than the standard deviation of the intake manifold pressure according to the prior art method.This can enable an internal combustion engine control unit to provide a smoother air-fuel ratio from the internal combustion engine, exhibiting less noise, thereby improving internal combustion engine emissions.

[0036] At time t3, the combustion engine intake ratio is reduced a third time (not shown) in response to the combustion engine operating conditions. The pure intake manifold pressure of the combustion engine is further increased as the intake ratio decreases, allowing the combustion engine to deliver a nearly constant amount of torque. The output size of the prior art filtration method increases in response to the increase in the pure intake manifold pressure of the combustion engine. The output size of the filter according to the present description also increases in response to the increase in the pure intake manifold pressure of the combustion engine. Coefficients for the filter according to the present description are set a third time in response to the change in the combustion engine intake ratio.

[0037] Between time t3 and time t4, the internal combustion engine is operating, although fewer than all of its cylinders are active (e.g., burning air and fuel). The standard deviation of the pure intake manifold pressure of the internal combustion engine remains large. The standard deviation of the output of the prior art filtration method also remains large. However, the filter output according to the present description provides a smoothed intake manifold pressure of the internal combustion engine, which allows for more precise control of the air-fuel ratio of the internal combustion engine. In other words, the standard deviation of the intake manifold pressure output from the filter according to the present description is smaller than the standard deviation of the intake manifold pressure according to the prior art method.This can enable an internal combustion engine control unit to provide a smoother air-fuel ratio from the internal combustion engine, exhibiting less noise, thereby improving internal combustion engine emissions.

[0038] At time t4, the combustion engine intake ratio is reduced a fourth time (not shown) in response to the combustion engine operating conditions. The pure intake manifold pressure of the combustion engine is further increased as the intake ratio decreases, allowing the combustion engine to deliver a nearly constant amount of torque. The output size of the prior art filtration method increases in response to the increase in the pure intake manifold pressure of the combustion engine. The output size of the filter according to the present description also increases in response to the increase in the pure intake manifold pressure of the combustion engine. Coefficients for the filter according to the present description are adjusted a fourth time in response to the change in the combustion engine intake ratio.

[0039] After time t4, the internal combustion engine is operating, although fewer than all of its cylinders are active (e.g., burning air and fuel). The standard deviation of the pure intake manifold pressure of the internal combustion engine remains large. The standard deviation of the output of the prior art filtration process also remains large. However, the filter output according to the present description provides a smoothed intake manifold pressure for the internal combustion engine, which allows for more precise control of the air-fuel ratio of the internal combustion engine.

[0040] In this way, a pure signal output from an internal combustion engine sensor can be filtered via a finite impulse response filter, and the filter coefficients can be adjusted each time to adapt a filter output in response to the internal combustion engine intake ratio and frequencies in the sensor output that may be associated with the internal combustion engine intake ratio.

[0041] With reference to Fig. Figure 4 shows a flowchart describing a method for operating an internal combustion engine. The method may involve filtering the output of an internal combustion engine sensor in response to an internal combustion engine intake ratio, and the coefficients of a filter that modifies the output of the internal combustion engine sensor may be adjusted in response to the internal combustion engine intake ratio. Adjusting the coefficients can improve the filter response and characteristics (e.g., standard deviation) of signals output from the filter. The method from Fig. 4 can be added to the system from the Fig. 1-2B be included and cooperate with it. Furthermore, at least parts of the procedure can be derived from Fig. 4. The instructions are included as executable instructions stored in non-volatile memory, while other parts of the procedure can be carried out via a controller that translates the operating states of devices and actuators into the physical domain. The vehicle's internal combustion engine rotates and burns air and fuel in at least one cylinder while the procedure 400 is active.

[0042] In case 402, procedure 400 determines an internal combustion engine intake ratio. In an example, the internal combustion engine intake ratio can be determined by the following equation: ir=nd where i rThe internal combustion engine intake ratio is , n is the actual total number of active cylinders (e.g., cylinders burning air and fuel), and d is the actual total number of internal combustion engine cylinders. For example, if the internal combustion engine has eight cylinders and three cylinders fire during an engine cycle, the internal combustion engine intake ratio for that engine cycle is 0.375. The internal combustion engine intake ratio can be changed in response to engine speed and load, as well as other internal combustion engine operating conditions. Procedure 400 transitions to 404.

[0043] In procedure 400, method 404 determines the order of a finite impulse response (FIR) or infinite impulse response (IIR) filter. The filter order determines the attenuation rate of frequencies in the filtered signal. The filter has a maximum gain of one, and frequencies that are attenuated are determined by the position of the filter's zeros. The attenuation rate for unwanted frequencies entering the filter increases with increasing filter order. However, the computational load for determining the filter output also increases with the filter order. The filter order can impair the filter output and the computational load for filtering a signal. In one example, the filter order is predetermined, and the number of filter coefficients is determined from the filter order. The filter order may depend on characteristics of the internal combustion engine and sensor output.For example, a second-order FIR filter can be applied to the output of a pressure sensor coupled to an eight-cylinder internal combustion engine. Conversely, a first-order FIR filter can be applied to the output of a pressure sensor coupled to a four-cylinder internal combustion engine. The order of the FIR filter can be determined empirically and stored in the control unit's memory. The filter order can be retrieved from memory by referencing memory according to the vehicle configuration. Procedure 400 transitions to 406.

[0044] At 406, the procedure retrieves 400 FIR or IIR filter coefficients from control memory. In one example, FIR filter coefficients can be empirically determined based on frequencies in the raw sensor output signal that may be undesirable. The filter coefficients can be selected to attenuate unwanted frequencies, and the unwanted frequencies can vary according to the given combustion engine intake ratio. In one example, a table or matrix of FIR coefficients is stored in control memory. The dimensions of the table or matrix can be N rows and M columns. The value of N is the maximum order of an FIR filter obtained from the table.For example, if the maximum order of the FIR filter is one (a first-order filter), the value N=2, where one table entry is reserved for each internal combustion engine intake ratio for a b0 coefficient and one table entry is reserved for each internal combustion engine intake ratio for a b1 coefficient. M is the actual total number of available internal combustion engine intake ratios. It should be noted that the order of the FIR filter can be set to zero by selecting appropriate filter coefficients. For example, if N=8, then the order of the FIR filter can be set between 0 and 7.

[0045] Thus, the dimensions of the matrix or table are based on the filter order and the internal combustion engine intake ratios. Filter coefficients for internal combustion engine intake ratios that do not have specific entries in the table or matrix can be interpolated or extrapolated. The empirically determined values ​​in the table or matrix can be referenced via the internal combustion engine intake ratio or the filter order. In some examples, the filter order may be fixed, and the table or matrix can only be referenced using the internal combustion engine intake ratio. Procedure 400 retrieves the filter coefficients and proceeds to 408.

[0046] In module 408, a sensor coupled to the internal combustion engine (e.g., a MAP sensor, a MAF sensor, an internal combustion engine speed sensor, a wastegate position sensor, or a camshaft position sensor) is polled at a predetermined frequency, and the raw sensor output is fed into the FIR or IIR filter. In other words, the FIR or IIR filter is applied to the output of an internal combustion engine sensor. For example, the FIR filter can be implemented according to the following equation: yk=∑i=0Nbiuk−i where y k where k is the output of the FIR filter, i is the time step, i is an indexing variable, b is an FIR filter coefficient, N is the order of the filter, and u k-i These are pure combustion engine sensor values ​​taken at defined query intervals. The filter can be expressed graphically, as in Fig. 5 shown. Procedure 400 transitions to 410 after the input from the combustion engine sensor has been filtered.

[0047] At step 410, procedure 400 determines whether a transition in the combustion engine intake ratio is currently occurring. For example, if the combustion engine intake ratio is currently or has just changed from a value of 0.8 to a value of 0.5, the answer is yes, and procedure 400 proceeds to step 412. Otherwise, the answer is no, and procedure 400 proceeds to step 414. Procedure 400 performs an evaluation of the combustion engine intake ratio so that the output of the filter from step 408 of this iteration of procedure 400 can be smoothed with the output of the filter from step 408 of the next iteration of procedure 400. In some examples, procedure 400 can be executed every time the combustion engine sensor is queried.

[0048] In Procedure 412, a second filter can be applied to the output of the FIR or IIR filter described in 408. The second filter can smooth out irregularities resulting from changes in filter coefficients and changes in sensor output that may be related to changes in the internal combustion engine intake ratio. In one example, the second filter can be another FIR filter; in another example, the second filter can be a first-order bandpass filter. Procedure 400 applies the second filter to the output of the FIR or IIR filter, and the filtered internal combustion engine intake manifold pressure is made available for calculating other variables within the control system. Procedure 400 transitions to 414.

[0049] In procedure 414, procedure 400 sets one or more internal combustion engine actuators in response to the output of the FIR or IIR filter, or the output of the second filter. Procedure 400 can set the one or more internal combustion engine actuators in response to the output of the second filter while a change in the internal combustion engine intake ratio is in progress, or within a predetermined actual number of internal combustion engine sensor queries following a change in the internal combustion engine intake ratio. For example, while a change in the internal combustion engine intake ratio is in progress, procedure 400 can set internal combustion engine actuators in response to the most recent value output from the second filter and the output of the second filter for the next five times procedure 400 is executed, each time following an internal combustion engine sensor query.However, if the internal combustion engine intake ratio has not changed and a predetermined total number of queries to the internal combustion engine sensor have been performed since the last change in the internal combustion engine intake ratio, the procedure 400 can adjust the internal combustion engine actuator in response to the output of the FIR filter.

[0050] Method 400 sets actuators that have positions or states based on filtered output from the internal combustion engine sensor. In one example, Method 400 sets fuel injection pulse widths in response to filtered internal combustion engine sensor output (e.g., output from the FIR or IIR filter, or the second filter). For example, if the sensor is a MAP sensor, the amount of fuel injected by a fuel injection device can be set in response to an internal combustion engine air volume (e.g., airflow through the internal combustion engine), where the internal combustion engine air volume is estimated from the filtered MAP sensor output and the ideal gas law. In another example, Method 400 sets the position of an EGR valve and throttle in response to a filtered MAP sensor output.In other examples, the timing of the internal combustion engine's camshaft can be adjusted in response to the filtered MAP sensor output. Procedure 400 concludes after the internal combustion engine actuators have been adjusted in response to the filtered output of the internal combustion engine sensor.

[0051] According to this, the procedure is Fig. 4. A method for operating an internal combustion engine is provided, comprising the following: receiving a signal to a controller; setting coefficients of a finite impulse response filter in response to an internal combustion engine intake ratio; filtering the signal (MAP, internal combustion engine airflow, or cam timing signals) through the finite impulse response filter; and setting one or more actuators in response to the filtered signal. The method involves determining the coefficients by reference to a matrix or table of predetermined coefficients in response to the internal combustion engine intake ratio and the order of the finite impulse response filter. The method further involves interpolation between entries in the matrix. The method involves the actuator being a fuel injection device. The method involves the actuator being a camshaft of the internal combustion engine.The method involves the actuator being a throttle of the internal combustion engine. The method involves the internal combustion engine intake ratio being the actual total number of cylinders burning air and fuel in one cylinder cycle, divided by the actual total number of internal combustion engine cylinders.

[0052] The procedure from Fig. Section 4 also provides an internal combustion engine operating procedure that includes: receiving a signal to a controller; retrieving coefficients of a finite impulse response filter from a table or matrix in the controller's memory by referencing the table or matrix via an internal combustion engine intake ratio; applying the coefficients of a finite impulse response filter; filtering the signal through the finite impulse response filter; and adjusting one or more actuators in response to the filtered signal. The procedure implies that the matrix is ​​an N x N matrix. The procedure implies that N is an actual overall order of the finite impulse response filter. The procedure implies that M is an internal combustion engine intake ratio. The procedure implies that the internal combustion engine intake ratio is adjusted in response to the internal combustion engine operating conditions.The method involves increasing the combustion engine intake ratio with the combustion engine load. The method further includes filtering the signal through a second filter in response to a change in the combustion engine intake ratio.

[0053] With reference to Fig. Figure 5 shows a graphical example of an FIR filter with coefficients set in response to the internal combustion engine intake ratio. A pure, unfiltered output from an internal combustion engine sensor is fed into the FIR filter and is represented as U k The internal combustion engine intake ratio refers to a lookup table or matrix 502, and the table gives the coefficients b0, b1, ... b NThe corresponding coefficients are multiplied by current and previous values ​​of the pure combustion engine sensor output in multiplication blocks 504, 510, 514, and 520. Blocks 506, 512, and 518 each represent a delay of one query. Outputs from the multiplication blocks are then added in summation blocks 508, 516, and 522. Furthermore, the output of summation block 508 is added to the output of multiplication block 514 and summation block 516. The output of the FIR filter is designated as Y. k specified and is the output of summing block 522.

[0054] It should be noted that the exemplary control and estimation routines contained herein can be used with various internal combustion engine and / or vehicle system configurations. The control methods and routines disclosed herein can be stored as executable instructions in non-volatile memory and can be executed by the control system, which includes the control unit in combination with the various sensors, actuators, and other internal combustion engine hardware. The specific routines described herein can represent one or more from any number of processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, and the like. Accordingly, various illustrated actions, operations, and / or functions can be performed in the illustrated sequence or in parallel, or in some cases, omitted.Similarly, the processing sequence is not strictly necessary to achieve the features and advantages of the exemplary embodiments described here, but is provided to facilitate illustration and description. One or more of the illustrated actions, operations, and / or functions can be performed repeatedly, depending on the specific strategy employed. Furthermore, at least some of the described actions, operations, and / or functions can graphically represent code to be programmed into non-volatile memory of the computer-readable storage medium in the control system.Furthermore, the control actions can transform the operating state of one or more sensors or actuators in the physical world when the described actions are carried out by executing the instructions in a system that includes the various internal combustion engine hardware components in combination with one or more controllers.

[0055] This concludes the description. A person skilled in the art will find many changes and modifications upon reading it, without altering the spirit and scope of the description. For example, the present description could be advantageously used for I3, I4, I5, V6, V8, V10, and V12 internal combustion engines operating on natural gas, gasoline, diesel, or alternative fuel configurations. Furthermore, the internal combustion engine may be turbocharged or supercharged.

[0056] According to the present invention, an internal combustion engine operating method is provided which comprises: receiving a signal to a controller; setting coefficients of a finite impulse response filter in response to an internal combustion engine intake ratio; filtering the signal through the finite impulse response filter; and setting one or more actuators in response to the filtered signal.

[0057] According to one embodiment, the coefficients are determined by reference to a matrix or table of predetermined coefficients in response to the combustion engine intake ratio and the order of the finite impulse response filter.

[0058] According to one embodiment, the above invention is further characterized by interpolation between entries in the matrix.

[0059] According to one embodiment, the actuator is a fuel injection device.

[0060] According to one embodiment, the actuator is a camshaft of the internal combustion engine.

[0061] According to one embodiment, the actuator is an internal combustion engine throttle and the signal is provided via a manifold absolute pressure sensor, an air mass sensor, an internal combustion engine speed sensor, a cam position sensor, an exhaust manifold pressure sensor or a wastegate position sensor.

[0062] According to one embodiment, the internal combustion engine intake ratio is the actual total number of cylinders that burn air and fuel in a cylinder cycle, divided by the actual total number of internal combustion engine cylinders.

[0063] According to the present invention, an internal combustion engine operating method is provided, comprising: receiving a signal to a controller; retrieving coefficients of a finite impulse response filter from a table or matrix in the controller's memory by referencing the table or matrix via an internal combustion engine intake ratio; applying the coefficients of a finite impulse response filter; filtering the signal through the finite impulse response filter; and adjusting one or more actuators in response to the filtered signal.

[0064] According to one embodiment, the matrix is ​​an N x N matrix.

[0065] According to one embodiment, N is an order of the filter with a finite impulse response.

[0066] According to one embodiment, M is a number of available internal combustion engine intake ratios.

[0067] According to one embodiment, the combustion engine intake ratio is adjusted in response to the combustion engine operating conditions.

[0068] According to one embodiment, the combustion engine intake ratio increases with the combustion engine load.

[0069] According to one embodiment, the above invention is further characterized by filtering the signal via a second filter in response to a change in the combustion engine intake ratio.

[0070] According to the present invention, an internal combustion engine system is provided comprising: an internal combustion engine including one or more cylinder valve deactivation mechanisms; a sensor coupled to the internal combustion engine; an actuator coupled to the internal combustion engine; a controller comprising executable instructions stored in non-volatile memory to selectively deactivate one or more internal combustion engine cylinders and to set coefficients of a finite impulse response filter applied to a signal generated via the sensor; instructions to apply a second filter to the output of the finite impulse response filter in response to a change in the internal combustion engine intake ratio; and instructions to apply the actuator in response to the output of the finite impulse response filter and the output of the second filter.

[0071] According to one embodiment, the foregoing invention is further characterized by additional executable instructions for setting the coefficients via value, which are stored in a table or matrix in the memory of the controller.

[0072] In one embodiment, the actuator is a fuel injection device. In another embodiment, the actuator is an internal combustion engine throttle. In another embodiment, the second filter is a low-pass filter.

[0073] According to one embodiment, the second filter consists of instructions stored in the control memory.

Claims

[1] Internal combustion engine operating procedures, comprising: Receiving a signal to a controller (12); Setting coefficients (b0, b1, ... b N ) of a filter with a finite impulse response in response to an internal combustion engine intake ratio (i r ); Filtering the signal through the finite impulse response filter; Filtering the output of the finite impulse response filter via a low-pass filter in response to a change in the combustion engine intake ratio (i r ); Non-filtering of the finite impulse response output of the low-pass filter in response to a lack of change in the combustion engine intake ratio; and Setting one or more actuators in response to the filtered signal. [2] Method according to claim 1, wherein the coefficients (b0, b1, ... b N) via references to a matrix or a table of predetermined coefficients (b0, b1, ... b N ) as a reaction to the combustion engine intake ratio and an order of the filter with a finite impulse response. [3] Method according to claim 2, further comprising interpolating between entries in the matrix. [4] Method according to claim 1, wherein an actuator of one or more actuators is a fuel injection device (66). [5] Method according to claim 1, wherein an actuator of one or more actuators is a camshaft (254) of the internal combustion engine. [6] Method according to claim 1, wherein an actuator of one or more actuators is an internal combustion engine throttle (62) and wherein the signal is provided via a manifold absolute pressure sensor (122), an air mass sensor (120), an internal combustion engine speed sensor (118), a cam position sensor (57, 59), an exhaust manifold pressure sensor (156) or a wastegate position sensor (156). [7] Method according to claim 1, wherein the internal combustion engine intake ratio is an actual total number of cylinders (1 - 8) that burn air and fuel in a cylinder cycle, divided by an actual total number of internal combustion engine cylinders. [8] Internal combustion engine operating procedures, comprising: Receiving a signal to a controller; Retrieving coefficients (b0, b1, ... b N) of a finite impulse response filter from a table or matrix in the controller's memory via references to the table or matrix via an internal combustion engine intake ratio (i r ); Applying the coefficients (b0, b1, ... b N ) on the finite impulse response filter; filtering the signal through the finite impulse response filter; Filtering the output of the finite impulse response filter via a low-pass filter in response to a change in the combustion engine intake ratio (i r ); Non-filtering of the output of the finite impulse response filter via the low-pass filter in response to a lack of change in the combustion engine intake ratio (i r ); and Setting up at least one actuator in response to the filtered signal. [9] Internal combustion engine system, comprising: an internal combustion engine that includes one or more cylinder valve deactivation mechanisms; a sensor that is coupled to the combustion engine; an actuator that is coupled to the internal combustion engine; a control system, including executable instructions stored in non-volatile memory, to selectively shut down one or more internal combustion engine cylinders and coefficients (b0, b1, ... b N ) of a finite impulse response filter applied to a signal generated via the sensor; instructions to set a second filter for the output of the finite impulse response filter in response to a change in the internal combustion engine intake ratio (i r ) to apply; and instructions to adjust the actuator in response to the output of the finite impulse response filter and the output of the second filter. [10] Internal combustion engine system according to claim 9, further comprising additional executable instructions to determine the coefficients (b0, b1, ... b N ) to set values ​​stored in a table or matrix in the controller's memory and not to apply the second filter to the output of the finite impulse response filter in response to a lack of change in the combustion engine intake ratio (i r ). [11] Internal combustion engine system according to claim 9, wherein the actuator is a fuel injection device. [12] Internal combustion engine system according to claim 9, wherein the actuator is an internal combustion engine throttle. [13] Internal combustion engine system according to claim 9, wherein the second filter is a low-pass filter. [14] Internal combustion engine system according to claim 9, wherein the second filter consists of instructions stored in the control memory.

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