RU2575675C2 - Fuel injection control in two-fuel ice - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: invention can be used in internal combustion engine fuel feed control systems. Claimed invention discloses the ICE operation whereat, in transient modes, amount of injected first fuel of the first reactivity is increased (decreased) and that of the second fuel of second reactivity is decreased (increased) subject to the amount of air forced into the ICE. Besides, the invention discloses the ICE system for implementation of proposed processes.

EFFECT: higher stability of combustion under ICE transient operating conditions.

19 cl, 11 dwg

Description

FIELD OF THE INVENTION

The present invention relates to dual-fuel engines, and more particularly to fuel injection systems comprising injectors for two different fuels.

State of the art

Controlled Reactivity Compression Ignition (RCCI) uses two fuels with different reactivity and multiple fuel injection to control the reactivity of the air-fuel mixture in the engine cylinders. In addition, one type of fuel has a lower reactivity compared to another type of fuel. A uniform charge is formed in the engine cylinder, including low reactivity fuel, exhaust gas recirculation (EGR) and air. As the piston in the cylinder compresses the homogeneous mixture, fuel with greater reactivity can be injected into the moment before ignition of the homogeneous mixture. Thus, it is possible to control the combustion of the air-fuel mixture to reduce the content of NOx and particulate matter in the exhaust gases, as well as improve fuel economy. However, changes in oxygen concentration in the cylinder and / or boost related to transient conditions of the engine can affect the charge composition of the mixture in the cylinder and degrade combustion characteristics.

Disclosure of invention

To overcome the above drawbacks, a method of engine operation was developed, which includes: increasing the amount of the first fuel with the first reactivity injected into the cylinder during a transition exceeding the threshold value, in response to an error in the concentration of oxygen supplied to the engine; a decrease in the amount of the second fuel with a second reactivity injected into the cylinder during the transition, in response to an error in the concentration of oxygen supplied to the engine; ignition of the first and second fuel from compression.

By adjusting the amount of fuel having different reactivity indicators injected into the cylinder during transient conditions in response to an error in the concentration of oxygen supplied to the engine, it is possible to improve the emission characteristics of the engine during the transition and at the same time provide the desired engine torque. For example, under steady state operating conditions, the concentration of oxygen supplied to the engine can be monitored, as a result of which the content of NOx and particulate matter in the exhaust gas can be reduced. However, under transient conditions, an error in the concentration of oxygen supplied to the engine may occur compared to the desired concentration of oxygen supplied to the engine.

The error in the concentration of oxygen supplied to the engine can be eliminated by increasing the amount of the first fuel with the first reactivity injected into the cylinder during the cycle of the cylinder, and reducing the amount of second fuel injected into the cylinder during the cycle of the cylinder. Thus, it is possible to control engine emissions during transient engine operating conditions in order to approach the engine emission characteristics at steady state under similar engine operating conditions.

An engine operating method may also include that the concentration error of oxygen supplied to the engine increases in response to a change in the air mass flow in the engine.

The present invention may provide several advantages. In particular, this approach can reduce harmful engine emissions under conditions of combustion in a fuel engine with different reactivity. In addition, this method can help to reduce the size of the devices for the subsequent processing of exhaust gases, due to the fact that improved emission characteristics in transient conditions of the engine. In addition, the method can improve vehicle controllability under certain conditions by providing the desired level of engine torque instead of misfiring or ignition vibrations.

The above and other advantages and characteristics of the present invention will be apparent from the following detailed description, taken separately or in conjunction with the accompanying drawings. It should be understood that the above disclosure of the invention is given to bring in a simplified form a number of selected concepts, the further description of which is given below in the detailed description. A summary of the invention is not aimed at determining the main or essential characteristics of the claimed subject matter, the scope of which is uniquely determined by the claims following the detailed description. In addition, the claimed subject matter is not limited to embodiments of the invention that address any of the disadvantages indicated above or in any part of this disclosure.

Brief Description of the Drawings

In FIG. 1 is a schematic illustration of an engine;

In FIG. 2-9 show exemplary operating sequences under transient engine operating conditions; and

In FIG. 10-11, a flow chart of an exemplary method for controlling the injection of two types of fuel with two different reactivity indices is presented.

The implementation of the invention

The present description relates to the control of fuel injection into an engine. In FIG. 1 illustrates one example of a direct injection and turbocharged engine, and the method illustrated in FIG. 10 and 11 can adjust the fuel injection to compensate for transient engine conditions. In FIG. 2-9 are examples of engine operating sequences for comparing differences between compensated and uncompensated transient engine operating conditions.

For main combustion during compression ignition with controlled reactivity, the injection of two types of fuel is determined empirically, and data on the moments of fuel injection and the injection quantity are placed in a table that can be indexed based on engine speed and load. Data on the moments of fuel injection and the amount injected are determined when the engine is running at a constant speed and constant load. The fuel injection moments and the injection quantity are adjusted to provide the desired combustion phasing, which controls the formation of particulate matter in the engine exhaust and NOx. However, if the moments of fuel injection and the amount of fuel injected that are determined for a steady state of engine operation (for example, engine speed and load are substantially constant) are applied when the engine's air charge, exhaust gas recirculation (EGR) flow or boost changes by an amount exceeding the threshold value, then due to changes in the engine mixture, the formation of additional NOx and particulate matter in the exhaust gases of the engine is possible. The method and system described herein controls fuel injection times (e.g., the moment the injection starts) and the amount of fuel injected, whereby the desired level of particulate matter and NOx in the exhaust gas can be achieved. In particular, the described method does not merely retrieve data about the moments of fuel injection at a steady state for two different types of fuel under transient conditions and displays corrected moments of injection. The method and system described herein controls the phasing of combustion under transient conditions by increasing the amount of one fuel and decreasing the amount of other fuel, while providing the desired torque. Thus, it is possible to control the phasing of combustion under transient conditions of engine operation.

As shown in FIG. 1, control of an internal combustion engine 10 comprising a plurality of cylinders, one of which is shown in FIG. 1, is carried out using an electronic controller 12 of the engine. The engine 10 comprises a combustion chamber 30 and cylinder walls 32 with a piston 36 disposed therein and connected to the crankshaft 40. The combustion chamber 30 is shown in communication with the intake manifold 44 and exhaust manifold 48 through a respective intake valve 52 and exhaust valve 54. Each intake and the exhaust valve can be actuated by the intake cam 51 and the exhaust cam 53. The position of the intake cam 51 can be detected by the intake cam sensor 55. The position of the exhaust cam 53 can be detected by the exhaust cam sensor 57.

The fuel injector 66 is shown arranged so as to inject fuel directly into the combustion chamber 30, which is known to specialists in this field as "direct injection". Fuel injector 66 delivers fuel in proportion to the pulse width of the FPW signal from controller 12. Fuel is supplied to fuel injector 66 by a fuel system (not shown) comprising a fuel tank, a fuel pump and a fuel relay (not shown). The pressure of the fuel supplied by the fuel system can be controlled by changing the position of the valve controlling the flow of fuel to the fuel pump (not shown). In addition, the metering valve is located inside or next to the fuel rail for full control of fuel consumption. In one example, fuel injector 66 delivers a first type of fuel with a high level of reactivity to the combustion chamber 30.

A fuel injector 68 is shown arranged so as to inject fuel into the intake manifold 44 for suction into the combustion chamber 30, which is known to those skilled in the art as injection into the inlet channel. Fuel injector 68 delivers fuel in proportion to the pulse width of the FPW signal from controller 12. In one example, fuel injector 68 delivers a second type of fuel with a lower level of reactivity to combustion chamber 30. Alternatively, fuel with less reactivity can be injected through an additional direct injector 67. Fuel with less reactivity can be supplied from a second fuel tank that is isolated from a fuel tank containing fuel with more reactivity. In one example, a fuel with a higher reactivity may be diesel fuel and a fuel with a lower reactivity may be gasoline. However, in other examples, diesel and gasoline can be replaced with other fuels. For example, fuels with greater and less reactivity can be diesel and alcohol.

The intake manifold 44 is shown in communication with an optional electronic throttle 62, which adjusts the position of the throttle valve 64 to control the air flow from the inlet discharge chamber 46. Compressor 162 draws air from the air intake 42 to be supplied to the discharge chamber 46. The exhaust gases untwist the turbine 164, which is connected to compressor 162 through shaft 161. In some cases, a charge air cooler may be installed. The speed of the compressor can be adjusted by adjusting the position of the controller 72 with rotary blades (bypass damper, west gate) or bypass valve 158 of the compressor. Regulator 72 allows exhaust gases to bypass turbine 164, thereby reducing the amount of energy entering the turbine. The bypass valve 158 of the compressor allows the compressed air at the output of the compressor 162 to return to the input of the compressor 162. In this case, the efficiency of the compressor 162 can be reduced to change the flow passing through the compressor 162.

Combustion is initiated in the combustion chamber 30 when the fuel is automatically ignited when the piston 36 reaches the top dead center of the stroke. In some examples, a Universal Exhaust Gas Oxygen (UEGO) sensor may be coupled to the exhaust manifold 48 upstream of the emission control device 70. In other cases, the UEGO sensor may be located downstream of one or more exhaust emission reduction devices. Alternatively, the UEGO sensor can be replaced with a NOx sensor (nitrogen oxide sensor).

An emission control device 70 may in one case include a particulate filter and catalytic units. Alternatively, multiple emission control devices may be used, each of which has several units. In one case, the emission control device 70 may include an oxidation catalyst. In other cases, the emission control device may include a lean NOx trap or an SCR (selective catalytic reduction) system.

The engine may be provided with recirculated exhaust gases through an EGR valve 80. EGR valve 80 is a three-way valve that shuts off or passes exhaust gases from a downstream emission reduction device 70 to a location in the engine intake system upstream of compressor 162. In alternative examples, recirculated exhaust gases may come from a location upstream of the 164 k turbine the intake manifold 44. The recirculated exhaust gas may bypass the EGR cooler 85 or, alternatively, the recirculated exhaust gas may be cooled by passing through 85 EGR cooler.

Controller 12 is shown in FIG. 1 as a conventional microcomputer, comprising: a microprocessor 102 (CPU), input and output ports 104, read-only memory 106 (ROM), random access memory 108 (RAM), non-volatile random access memory 110 (KAM) and a conventional data bus. The controller 12 is shown receiving various signals from sensors connected to the engine 10. In addition to the signals described above, the controller also receives data about the temperature of the engine coolant (ECT) from the temperature sensor 112 connected to the cooling channel 114; a position sensor 134 connected to the gas pedal 130 for measuring a pressing force by a foot 132; measuring the pressure in the engine manifold (MAP) from a pressure sensor 121 connected to the intake manifold 44; about the boost pressure from the pressure sensor 122, about the concentration of oxygen in the exhaust gases from the oxygen sensor 126; about the phase of the engine from the sensor 118 on the Hall effect, reading the position of the crankshaft 40; the readings of the sensor 120 of the air mass entering the engine (for example, a heat meter air flow); and indications of the throttle position of the sensor 58. Also, for the controller 12, barometric pressure can be measured (sensor not shown). According to a preferred embodiment of the invention, the Hall effect sensor 118 generates a predetermined number of uniform pulses in each crankshaft cycle, based on which the engine speed (RPM) can be determined.

In some examples, in a hybrid vehicle, the engine may be coupled to an electric motor / battery system. A car with a hybrid drive can have parallel and serial configurations, as well as their combinations and variations.

During operation, each cylinder in the engine 10 usually goes through 4 duty cycles: inlet, compression, stroke and exhaust. During the inlet, the outlet valve 54 is typically closed and the inlet valve 52 is opened. Air enters the combustion chamber 30 through the intake manifold 44, and the piston 36 moves toward the bottom of the cylinder so as to increase the volume inside the combustion chamber 30. The position in which the piston 36 is near the bottom of the cylinder and at the end of its stroke (i.e. when the combustion chamber 30 has the largest volume) is usually called specialists in this field the bottom dead center (BDC). During the compression stroke, the inlet valve 52 and the exhaust valve 54 are closed. The piston 36 moves towards the cylinder head to compress the air inside the combustion chamber 30. The point at which the piston 36 is at the end of its stroke and closest to the cylinder head (ie, when the combustion chamber has the smallest volume) is usually called specialists in given area of top dead center (TDC). In the process, hereinafter referred to as “injection”, the fuel enters the combustion chamber. In the process, hereinafter referred to as “ignition”, the injected fuel is ignited using known ignition methods, such as spark plug 92, which leads to combustion. During the stroke, the expanding gases push the piston 36 back to the BDC. The crankshaft 40 converts the movement of the piston into the torque of the rotating shaft. Finally, during the course of the discharge, the exhaust valve 54 is opened to release the ignited mixture of air and fuel into the exhaust manifold 48, and the piston returns to the TDC. It can be noted that the foregoing is given by way of example only, and the timing of opening and / or closing of the intake and exhaust valves may be varied so as to provide positive or negative valve closure, late closing of the intake valve, or various other options. In addition, in some cases, instead of a four-stroke cycle, a push-pull cycle can be used.

Thus, the system of FIG. 1 is an engine system including: a diesel injector injecting diesel fuel directly into an engine cylinder, a diesel fuel having a first reactivity index; a second fuel injector injecting a second type of fuel into the engine cylinder, the second type of fuel having a second reactivity index; and a controller that contains instructions for increasing the amount of diesel fuel at a steady state, scheduled for injection, based on an error in the amount of air supplied to the engine during the transition of the operating state of the engine, a controller that further contains instructions for reducing the amount of second fuel at a steady state, planned for injection, based on an error in the amount of air supplied to the engine during the transition. This engine system includes additional controller instructions to increase the amount of diesel fuel in a steady state, planned for injection, based on boost error during the transition of the engine operation state. The engine system contains additional controller instructions to reduce the amount of second fuel in a steady state, planned for injection, based on boost error during the transition. In one example, the engine system comprises a second fuel injector, which is a fuel injector for injection into the inlet channel. The engine system also provides options where the second fuel injector is a direct fuel injection injector, the second type of fuel being gasoline, compressed natural gas, liquefied propane gas or alcohol, and when the start time of the second fuel injection is controlled in response to the transition. The engine system also includes additional controller instructions to reduce the amount of diesel fuel at a steady state scheduled for injection, based on an error in the amount of air supplied to the engine, includes additional instructions for regulating the amount of diesel fuel at a steady state scheduled for injection, by based on the temperature of the air supplied to the engine.

Turning now to FIG. 2-9, which show seven control parameters of the engine for different operating conditions. In each of FIG. 2-9, the same engine control parameters are shown under different engine operating conditions. In each of FIG. 2, 4, 6, and 8 control parameters of the engine are shown when the operation of the engine is not compensated by controlling the injection of two types of fuel with different reactivity indices. In each of FIG. Figures 3, 5, 7, and 9 show the engine control parameters under conditions when the engine operation is compensated by regulating the injection of two types of fuel with different reactivity indices.

In the first top graph of FIG. Figure 2-9 shows the engine torque request. A request for engine torque can be transmitted through an input signal from the operator (for example, through the gas pedal) or through the engine controller. The X axis represents time, which increases from right to left. The y-axis represents the amount of request for engine torque, which increases in the direction of the arrow of the y-axis.

In the second top graph of FIG. 2-9 show the phase of combustion in the engine (for example, the location of the maximum pressure in the cylinder). The combustion phase can be changed by adjusting the moment of fuel injection, a small amount of fuel with more and less reactivity, and the temperature of the air-fuel mixture. The X axis represents time, which increases from right to left. The Y-axis shows the combustion phase in the engine, which increases in the direction of the arrow of the Y-axis.

In the third top graph of FIG. Figure 2-5 shows the desired and actual engine boost (for example, the level of compressed air supplied to the engine through a compressor). The desired boost is indicated by a solid line, while the actual boost is indicated by a dashed line. The boost value can be adjusted by changing the position of the variable geometry turbocharger nozzle, the exhaust gas bypass flap or the compressor bypass valve. The X axis represents time, which increases from right to left. The Y-axis shows the engine boost level, which increases in the direction of the Y-axis arrow.

In the third top graph of FIG. 6-9 show the desired and actual concentration of oxygen supplied to the engine. The oxygen concentration can be adjusted by changing the position of the EGR valve, throttle, or when the engine valve opens or closes. The desired oxygen concentration is shown by a solid line, while the actual oxygen concentration is shown by a dashed line. The X axis represents time, which increases from right to left. The y-axis represents the EGR value of the engine, which increases in the direction of the arrow of the y-axis.

In the fourth top graph of FIG. 2-9 show the amount of fuel with greater reactivity from the two types of fuel injected into the engine. The amount of fuel with greater reactivity can be adjusted by increasing the duration of the pulse supplied to the fuel injector, increasing the pressure of the fuel or increasing the pressure of the fuel and the duration of the fuel injection pulse. The X axis represents time, which increases from right to left. The Y axis represents the amount of fuel with greater reactivity, which increases in the direction of the arrow of the Y axis.

In the fifth top graph of FIG. 2-9 show the moment of fuel injection with greater reactivity of the two types of fuel injected into the engine. The moment of fuel injection with greater reactivity can be adjusted by adjusting the start of the fuel injection pulse relative to the engine crankshaft. The X axis represents time, which increases from right to left. The Y axis shows the phase of the distribution (synchronization) of fuel injection times relative to the crankshaft of the fuel engine with greater reactivity, which shifts in the direction of the arrow of the Y axis.

In the sixth top graph of FIG. 2-9 show the amount of fuel with less reactivity of the two types of fuel injected into the engine. The amount of fuel with less reactivity can be adjusted by increasing the duration of the pulse supplied to the fuel injector or by increasing the fuel pressure. The X axis represents time, which increases from right to left. The Y axis represents the amount of fuel with less reactivity, which increases in the direction of the arrow of the Y axis.

In the seventh top graph of FIG. 2-9 show the moment of fuel injection with less reactivity of the two types of fuel injected into the engine. The moment of fuel injection with less reactivity can be adjusted by adjusting the start of the fuel injection pulse relative to the engine crankshaft. The X axis represents time, which increases from right to left. The Y axis shows the phase of the distribution of moments of fuel injection with less reactivity relative to the crankshaft of the engine, which moves in the direction of the arrow of the Y axis.

Turning now to FIG. 2, which shows signals of interest during an uncompensated change in torque and boost. In the example shown in FIG. 2, there is a decrease in the requested engine torque. A vertical mark 240 indicates the beginning of a change in engine operating conditions. A vertical mark of 250 indicates the end of a change in engine operating conditions. In the example shown in FIG. 2, the desired and actual pressurization are substantially equal up to a vertical mark of 240 and after a vertical mark of 250.

At section 202, the engine torque request changes from a higher level to a lower level. The desired boost is also reduced, as shown in section 206, since less boost is required to match the desired torque. However, the actual boost 208 continues to be at a higher level until the pressure is released by the pressure cylinders at a vertical elevation of 250. The boost error is represented by the area between curve 206 and curve 208. As a result of excessive boost at the beginning, the combustion phase goes to the next phase after torque request changes. Over time, the combustion phase stabilizes late at the moment after the vertical mark 250. Thus, before the torque request passes at 202, the phasing of the combustion is on the first distribution of injection moments, and the phasing of the combustion goes to the second distribution of injection moments, related to the amount of injected fuel , the moment of fuel injection and the properties of the air-fuel mixture (for example, the reactivity of the mixed fuel composition formed by the fuel injection with greater reactivity and opliva less reactivity) when vertical mark 250.

The amount of fuel with greater reactivity injected into the engine decreases in section 210 in response to a decrease in torque in section 202. Similarly, the amount of fuel with less reactivity injected in the engine decreases in section 214 in response to a decrease in engine torque in section 202. In addition, the moment of injection of fuel with greater reactivity is delayed in section 212 in response to a change in torque in section 202. The moment of injection of fuel with less reactivity remains constant, so ak this fuel is injected through the inlet channel.

Thus, without compensating for the difference between the desired and actual boost levels, the phasing of the combustion can be shifted, with a consequent increase in the possibility of deterioration in engine emission characteristics. In addition, the engine torque may follow the phasing of combustion, and thus may follow a less desirable path, as a result of which the engine control device may experience interference from misfire or undesired torque changes.

Turning now to FIG. 3, which shows the signals of interest for a compensated change in torque and boost. In the example shown in FIG. 3, the requested engine torque is reduced. Vertical mark 340 indicates the beginning of changes in engine operating conditions. A vertical mark 350 indicates the completion of a change in engine operating conditions. In the example shown in FIG. 3, the desired and actual boost levels are substantially equal up to the vertical mark 340 and after the vertical mark 350.

At section 302, the engine torque request changes from a higher level to a lower level. The desired boost is also reduced, as shown in section 306, since less boost is required to match the desired torque. However, the actual boost 308 continues to be at a higher level until the pressure is released by the pressure cylinders at the vertical mark 350. The boost error is represented by the area between curve 306 and curve 308. In the example shown in FIG. 3, excessive boost does not cause fluctuations in the combustion phase, as in the example of FIG. 2, since the injection of fuel with greater reactivity and fuel with less reactivity is adjusted. The combustion phase stabilizes shortly after stabilizing the torque in section 302. Thus, before the request for torque in section 302 passes, the phasing of combustion is in the first distribution of injection moments and switches to the second distribution of injection moments, related to the amount of fuel injected, the moment of fuel injection and the properties of the air-fuel mixture (for example, the reactivity of a mixed fuel composition formed by injecting fuel with greater reactivity and fuel with less reactive ) after requesting a torque in section 302, but well before vertical mark 350, when the desired and actual boost levels are substantially equal. In the future, the tendency of the phasing of the combustion to oscillate may be less due to the achievement of a stable distribution of the phases of the combustion at a stable state of engine operation after the transition of engine torque.

The amount 310 of compensated fuel with greater reactivity injected into the engine decreases in response to a decrease in torque in section 302 and / or the desired boost in section 306. The amount of 310 compensated fuel with more reactivity decreases more than the amount of 312 uncompensated fuel with more reactivity. The amount 320 of compensated fuel with less reactivity injected into the engine is reduced to a lesser extent than the amount of 318 uncompensated fuel with less reactivity injected into the engine in response to a decrease in torque in section 302 and / or desired boost. The moment of injection 314 of compensated fuel with greater reactivity is characterized by a greater delay than the moment of injection 316 of uncompensated fuel with greater reactivity, in response to a change in torque at section 302 and / or the desired boost. The moment of fuel injection with less reactivity remains constant, because this fuel is injected through the inlet channel.

Thus, the installation of the injection moment (for example, the moment of the beginning of fuel injection) and the amount of injected fuel of two types with different reactivity can compensate for the difference between the desired and actual boost during a transition state exceeding the threshold level. Thus, it is possible to control the phasing of combustion and the pressure in the cylinder so as to reduce the possibility of deterioration in engine emission characteristics. In addition, the propensity of the engine torque to change following the transition when the engine boost is behind the desired engine boost may be less. Therefore, for engine operating conditions that accelerate combustion (for example, a higher boost, a higher temperature of the intake mixture, an increased concentration of oxygen absorbed into the engine), an additional amount of fuel with less reactivity can be injected into the engine, while the amount of fuel with more reactivity injected into the engine is reduced. Thus, the distribution of the combustion phases can be adjusted to the desired distribution of the combustion phases, and the engine torque can correspond to the desired engine torque in order to improve the engine torque response and the emission composition. Alternatively, for engine operating conditions that slow down combustion (for example, less boost, lower intake temperature, lower oxygen concentration in the air-fuel mixture), a reduced amount of fuel with less reactivity can be injected into the engine, while the amount of fuel with more reactivity injected into the engine increases. In addition, in conditions of excessive boost or a small fraction of the exhaust gas, the injection moments of the two types of fuel can be adjusted under a transitional condition to reduce engine noise and NOx. On the other hand, in conditions of reduced boost or a large fraction of exhaust gases, the injection moments of two types of fuel can be adjusted during the transition to reduce misfire, torque disturbances, carbon monoxide (CO) and hydrocarbon (HC) emissions.

Turning now to FIG. 4, which shows signals of interest with an uncompensated change in torque and boost. In the example shown in FIG. 4, an increase in the requested engine torque occurs. Vertical mark 440 indicates the beginning of a change in engine operating conditions. A vertical mark of 450 indicates the completion of a change in engine operating conditions. In the example shown in FIG. 4, the desired and actual pressurization are substantially equal to the vertical mark 440 and after the vertical mark 450.

At 402, the engine torque request changes from a lower level to a higher level. The desired boost is also increased, as shown in section 404, since additional boost is required to match the desired torque. However, the actual boost 406 continues to remain lower until the pressure increases with the help of a compressor that corresponds to the vertical mark 450. The boost error is represented by the area between curve 404 and curve 406. The decrease in boost results in the initial delay of the combustion phase after changing the requested torque moment. Over time, the combustion phase stabilizes on the distribution of injection moments, shifted towards the acceleration, after the vertical mark 450. Thus, before the requested torque in section 402 passes, the phasing of combustion is on the first distribution of injection moments, and the phasing of combustion switches to the second distribution of injection moments, associated with the amount of fuel injected, the moment of fuel injection and the properties of the air-fuel mixture (for example, the reactivity of the mixed fuel composition, is formed th injection with greater reactivity and a lower reactivity fuel) after vertical mark 450.

The amount of 410 fuel with a higher reactivity injected into the engine increases in response to an increase in engine torque in section 402. Similarly, the amount of 414 fuel with less reactivity injected in an engine increases in response to an increase in torque in section 402. In addition, the distribution of 412 moments of fuel injection with greater reactivity is shifted from the lead side in response to a change in engine torque in section 402. The distribution of moments of fuel injection with a lower reactivity activity remains constant, since this fuel is injected through the inlet.

Thus, without compensating for the difference between the desired and actual boost with increasing boost, the phasing of the combustion can be shifted, increasing the likelihood of deterioration of the emission characteristics of the engine. In addition, the engine torque may follow the phasing of combustion and may follow a less desirable path, as a result of which the engine control unit may experience interference.

Turning now to FIG. 5, which shows the signals of interest for a compensated change in torque and boost. In the example shown in FIG. 2, an increase in the requested engine torque occurs. A vertical mark 540 indicates the beginning of a change in engine operating conditions. A vertical mark 550 indicates the completion of a change in engine operating conditions. In the example shown in FIG. 5, the desired and actual pressurization are substantially equal to the vertical mark 540 and after the vertical mark 550.

At 502, the requested torque changes from a lower level to a higher level. The desired boost is also increased, as shown in section 504, since less boost is required to match the desired torque. However, the actual boost 506 remains at a lower level until the compressor builds up pressure, which corresponds to the vertical mark 550. The boost error is represented by the area between curve 504 and curve 506. In the example shown in FIG. 5, the reduced boost does not lead to a fluctuation in the combustion phase, as in FIG. 4, since the injection of fuel with greater reactivity and fuel with less reactivity is adjusted. The combustion phase stabilizes shortly after stabilization of the requested torque in section 502. Thus, prior to the transition of the requested torque in section 502, the phasing of combustion is in the first distribution of injection moments and switches to the second distribution of injection moments related to the amount of injected fuel and the moment of fuel injection and the properties of the air-fuel mixture (for example, the reactivity of a mixed fuel composition formed by injecting fuel with greater reactivity and top willow less reactivity), when the requested torque to portion 502, but before long vertical mark 550, when the desired and actual boost levels are substantially equal. In addition, the tendency of the phasing of the combustion to oscillate until a steady state of phasing is achieved when the engine operating conditions are stable after the transition of the engine torque is less.

The amount 508 of compensated fuel with greater reactivity injected into the engine increases in response to an increase in engine torque in section 502 and / or the desired boost in section 504. The amount of 508 compensated fuel with more reactivity increases more than the amount of uncompensated fuel with more reactivity 510. The amount of 522 compensated fuel with less reactivity injected into the engine is reduced to a lesser extent compared to the amount of 520 uncompensated about fuel with less reactivity injected into the engine, in response to a decrease in torque in section 502 and / or desired boost 504. The distribution of 512 injection moments of compensated fuel with more reactivity is more advanced than the distribution of 514 injection moments of uncompensated fuel with greater reactivity, in response to a change in engine torque in section 502 and / or the desired boost 504. The distribution of fuel injection moments with less reactivity remains tinuous, since a fuel is injected through the inlet channel.

Thus, by compensating for the difference between the desired and actual boost when the boost increases, the phasing of the combustion can be controlled in order to reduce the likelihood of degradation of the emission characteristics. In addition, the propensity of the engine torque to change due to a shift in conditions where the actual engine boost is behind the desired engine boost may be less.

Turning now to FIG. 6, which shows signals of interest with an uncompensated change in torque and oxygen concentration supplied to the engine. In the example shown in FIG. 6, the requested engine torque is reduced. Vertical mark 640 indicates the beginning of a change in engine operating conditions. A vertical mark 650 indicates the completion of a change in engine operating conditions. In the example shown in FIG. 6, the desired and actual concentrations of air supplied to the engine are substantially equal up to a vertical mark of 640 and after a vertical mark of 650.

At 602, the requested engine torque is changed from a higher level to a lower level. The desired concentration of oxygen supplied to the engine also increases, as shown in section 606. However, the actual concentration of oxygen 608 supplied to the engine continues to remain lower until oxygen is added by the intake manifold through the engine air intake at a vertical mark of 650. A reduced oxygen concentration results to the initial delay of the combustion phase after changing the requested torque. Over time, the combustion phase stabilizes in the advanced phase, after a vertical mark of 650. Thus, before the requested torque passes to the plot 602, the phasing of the combustion is on the first distribution of injection moments, and switches to the second distribution of injection moments, related to the amount of injection fuel, the moment of fuel injection and the properties of the air-fuel mixture (for example, the reactivity of the composition of the mixed fuel formed by injecting fuel with greater reactivity fuel and fuel with less reactivity), after a vertical mark of 650.

The amount of fuel injected into the engine with more reactivity 610 decreases in response to a decrease in engine torque in section 602. Similarly, the amount 614 of fuel injected into the engine with less reactivity decreases in response to a decrease in engine torque in section 602. In addition, the distribution of 612 moments fuel injection with greater reactivity is delayed in response to a change in engine torque in section 602. The distribution of fuel injection moments with less reactivity remains toyannym, since a fuel is injected through the inlet channel.

Thus, without compensating for the difference between the desired and the actual concentration of oxygen supplied to the engine, the phasing of the combustion can be shifted, which increases the possibility of deterioration of the emission characteristics of the engine. In addition, the engine torque may follow the phasing of combustion and may follow a less desirable path, as a result of which the engine control unit may experience interference.

Turning now to FIG. 7, which shows the signals of interest for a compensated change in torque and EGR. In the example shown in FIG. 7, the requested engine torque is reduced. Vertical mark 740 marks the beginning of a change in engine operating conditions. A vertical mark 750 indicates the end of a change in engine operating conditions. In the example shown in FIG. 7, the desired and actual concentration of oxygen supplied to the engine is substantially equal up to a vertical mark of 740 and after a vertical mark of 750.

At section 702, the requested engine torque is changed from a higher level to a lower level. The desired concentration of oxygen supplied to the engine increases, as shown in section 706, since under the present engine operating conditions less EGR is required. However, the actual concentration of air 708 supplied to the engine continues to remain at a lower level until the concentration of oxygen supplied to the engine increases through the engine air intake located upstream of the throttle, as shown at vertical elevation 750. In other examples, the desired concentration level of oxygen supplied to the engine may increase in response to reduced torque. Thus, FIG. 7 is presented for purposes of illustration and is not intended to limit the system and methods disclosed herein. In the example shown in FIG. 7, a lower concentration of air supplied to the engine does not lead to fluctuations in the combustion phase, as in FIG. 6, since the injection of fuel with greater reactivity and fuel with less reactivity is adjusted. The combustion phase stabilizes shortly after stabilization of the requested torque in section 702. Thus, before the requested torque passes in section 702, the phasing of combustion is in the first distribution of injection moments and switches to the second distribution of injection moments associated with the amount of injected fuel and the moment of fuel injection and the properties of the air-fuel mixture (for example, the reactivity of a mixed fuel composition formed by injecting fuel with greater reactivity and top willow less reactivity) after torque request portion 702, but before long vertical mark 750, when the desired and actual levels of concentration of oxygen supplied to the engine are substantially equal. In addition, the tendency of the phasing of combustion to oscillate until a steady state of phasing of combustion is achieved when the engine operating conditions are stable after the transition of engine torque is less.

The amount 712 of compensated fuel with greater reactivity injected into the engine decreases in response to a decrease in engine torque in section 702 and / or an increase in the desired concentration of oxygen supplied to the engine in section 706. The amount of 712 compensated fuel with more reactivity decreases to a lesser extent. than the amount of 714 uncompensated fuels with greater reactivity. The amount 722 of compensated fuel injected into the engine with less reactivity is reduced to a greater extent than the amount 720 of uncompensated fuel injected into the engine with less reactivity, in response to a decrease in torque in section 702 and / or a reduced concentration of oxygen supplied to the engine. The distribution of 716 moments of injection of compensated fuel with greater reactivity is delayed to a greater extent than the distribution of 718 moments of injection of uncompensated fuel with greater reactivity, in response to a change in engine torque in section 702 and / or an increased desired concentration of oxygen 706 supplied to the engine. The distribution of moments of fuel injection with less reactivity remains constant, since this fuel is injected through the inlet channel.

Thus, by compensating for the difference between the desired and actual concentration of oxygen supplied to the engine, the phasing of the combustion can be controlled in order to reduce the possibility of deterioration of the emission characteristics of the engine. In addition, the tendency of the engine torque to change due to a transition under conditions where the concentration of oxygen supplied to the engine is behind the desired concentration of oxygen supplied to the engine may be less.

Turning now to FIG. 8, which shows the signals of interest with an uncompensated change in torque and oxygen concentration supplied to the engine. In the example of FIG. 8, an increase in the requested torque occurs. Vertical mark 840 marks the beginning of a change in engine operating conditions. A vertical mark of 850 indicates the completion of a change in engine operating conditions. In the example shown in FIG. 8, the desired and actual concentrations of oxygen supplied to the engine are substantially equal up to a vertical mark of 840 and after a vertical mark of 850.

At 802, the requested torque changes from a lower level to a higher level. The desired concentration of oxygen supplied to the engine is reduced, as shown in section 804. However, the actual concentration of oxygen supplied to the engine 806 remains at a higher level until oxygen is pumped out through the engine’s pressure cylinders at a vertical elevation of 850. Reduced concentration of oxygen supplied to the engine leads to an initial shift in the distribution of injection moments in the lead after changing the requested torque. Over time, the combustion phase stabilizes at a greater delay after a vertical mark of 850. Thus, prior to the transition of the requested torque in section 802, the phasing of the combustion is on the first distribution of injection moments, and transfers to the second distribution of injection moments, related to the amount of fuel injected, the moment of fuel injection and properties of the air-fuel mixture (for example, the reactivity of a mixed fuel composition formed by injecting fuel with greater reactivity and fuel with m nshey reactivity) after vertical mark 850.

The number 810 of fuel injected into the engine with greater reactivity increases in response to an increase in torque in section 802. Similarly, the number 814 of fuel injected into the engine with less reactivity increases in response to an increase in torque in section 802. In addition, the distribution of 812 injection moments fuel with a higher reactivity is advanced in response to a change in engine torque in section 802. Distribution of moments of fuel injection with less reactivity It ceases constant, since a fuel is injected through the inlet channel.

Thus, without compensating for the difference between the desired and actual concentration of oxygen supplied to the engine, with a decrease in the concentration of oxygen supplied to the engine, the phasing of the combustion can be shifted, increasing the likelihood of deterioration of the emission characteristics of the engine. In addition, the engine torque may follow the phasing of combustion and may follow a less desirable path, as a result of which the engine control unit may experience interference.

Turning now to FIG. 9, which shows the signals of interest with a compensated change in torque and oxygen concentration supplied to the engine. In the example shown in FIG. 9, an increase in the requested engine torque occurs. Vertical mark 940 marks the beginning of a change in engine operating conditions. A vertical mark of 950 indicates the completion of a change in engine operating conditions. In the example shown in FIG. 9, the desired and actual concentrations of oxygen supplied to the engine are substantially equal up to a vertical mark of 940 and after a vertical mark of 950.

At section 902, the requested torque changes from a lower level to a higher level. The desired concentration of oxygen supplied to the engine is reduced, as shown in section 904, since the engine can operate with additional EGR. However, the actual concentration 906 of oxygen supplied to the engine continues to remain at a higher level until the amount of oxygen decreased by pumping produced by the engine cylinders at a vertical mark of 950. In other examples, the level of the desired concentration of oxygen supplied to the engine may increase in response to an increase in the requested torque. moment. Thus, FIG. 9 is presented for purposes of illustration and is not intended to limit the system and methods disclosed herein. In the example shown in FIG. 9, the increased concentration of oxygen supplied to the engine does not lead to fluctuations in the combustion phase, as in FIG. 8, since the injection of fuel with greater reactivity and fuel with less reactivity is adjusted. The combustion phase stabilizes shortly after stabilization of the requested torque in section 902. Thus, prior to the transition of the requested torque in section 902, the phasing of the combustion is in the first distribution of injection moments and switches to the second distribution of injection moments related to the amount of injected fuel, the moment of injection of fuel and properties of a fuel-air mixture (for example, the reactivity of a mixed fuel composition formed by injecting fuel with greater reactivity and fuel willow with less reactivity), after requesting torque in section 902, but well before the vertical mark of 950, when the desired and actual concentrations of oxygen supplied to the engine are essentially equal. In addition, the tendency of the phasing of combustion to oscillate until a steady state of phasing of combustion is achieved when the engine operating conditions are stable after the transition of engine torque is less.

The amount of 912 compensated fuel injected into the engine with greater reactivity increases in response to an increase in engine torque in section 902 and / or a reduced desired concentration of oxygen supplied to the engine in section 904. The amount of 912 compensated fuel with greater reactivity increases to a lesser extent than 910 uncompensated fuels with greater reactivity. The amount of 918 compensated fuel injected into the engine with less reactivity increases to a greater extent than the amount 920 of uncompensated fuel injected into the engine with less reactivity in response to an increase in engine torque in section 902 and / or a reduced desired concentration of oxygen supplied to the engine in section 904 The distribution of 916 moments of injection of compensated fuel with a higher reactivity is shifted to the front to a lesser extent than the distribution of m uncompensated fuel injection moments with greater reactivity in response to a change in engine torque in section 902 and / or a reduced desired concentration of oxygen supplied to the engine in section 904. The distribution of fuel injection moments with less reactivity remains constant, since this fuel is injected through the inlet channel.

Thus, by compensating for the difference between the desired and actual concentrations of oxygen supplied to the engine while decreasing the concentration of oxygen supplied to the engine, the phasing of combustion can be controlled in order to reduce the likelihood of degradation of emissions. In addition, the tendency of the engine torque to change due to a transition under conditions where the concentration of oxygen supplied to the engine is behind the desired concentration of oxygen supplied to the engine may be less.

Turning now to FIG. 10 and 11, which shows a flowchart of an example method for controlling the injection of two types of fuel with different reactivity indices. The method shown in FIG. 10 and 11 may be implemented using the instructions of the controller 12 of FIG. 1. Furthermore, the method of FIG. 10 and 11 may provide control of engine parameters, as illustrated in FIG. 2-9.

At 1002, method 1000 determines whether a change in one or more path parameters of the air flow into the engine occurs. For example, method 1000 determines whether changes in EGR, boost, or engine air value occur. In one example, a change in EGR, boost or engine air value exceeds a threshold value for a change in EGR, boost or engine air value to fall within the definition of a transition state. The change in EGR value can be determined by monitoring the position of the EGR valve or by changing the air mass, manifold pressure, and temperature that are introduced into the engine. The change in the amount of air in the engine can be determined based on the position of the throttle. The change in the concentration of oxygen supplied to the engine can be determined based on the output value of the oxygen sensor. If the change in one or more path parameters of the air flow to the engine exceeds a threshold value, method 1000 proceeds to step 1004. Otherwise, method 1000 ends.

The rate of change of the parameters or variables of the engine air intake system may be less than the rate at which the fuel supplied to the engine can change. For example, the distribution of injection moments can be changed between combustion events in the engine cylinders, while the complete transition of the boost or EGR from the first steady state to the second steady state can take several seconds. Therefore, it is desirable to adjust the distribution of fuel injection times and the amount of fuel injected in order to compensate for slowly changing parameters or variables of air intake into the engine.

At 1004, method 1000 determines whether there is an error in the concentration of oxygen supplied to the engine. The error in the concentration of oxygen supplied to the engine can be determined by determining the difference between the desired concentration of oxygen supplied to the engine and the actual concentration of oxygen supplied to the engine. The desired concentration of oxygen supplied to the engine can be determined empirically when testing the engine to provide the desired engine emissions. In one example, a table of desired oxygen concentration values supplied to the engine is indexed based on engine speed and torque value. The desired concentration values of oxygen supplied to the engine are based on steady state conditions of the engine (for example, when engine operating conditions change by an amount that is less than a threshold value). If there are changes in the concentration of oxygen supplied to the engine, method 1000 proceeds to step 1006. Otherwise, method 1000 proceeds to step 1024.

At 1006, method 1000 determines whether the error in the concentration of oxygen supplied to the engine is positive. A positive error indicates that the actual concentration of oxygen supplied to the engine is less than the desired concentration of oxygen supplied to the engine. If method 1000 determines that the concentration error of oxygen supplied to the engine is positive, method 100 proceeds to step 1018. Otherwise, method 1000 proceeds to step 1008.

At 1008, method 1000 reduces the amount of fuel with greater reactivity injected into the engine to the amount of fuel with greater reactivity injected into the engine under steady-state engine conditions. For example, if the amount of fuel injected at steady state decreases in accordance with the change in engine speed and load, then even less fuel is injected into the engine than planned according to the amount of fuel injected at steady state. Less fuel with greater reactivity can be injected into the engine by reducing the fuel pressure and / or reducing the amount of time that the nozzle is open. By reducing the amount of fuel injected into the engine with greater reactivity, when the concentration error of the oxygen supplied to the engine is negative, the increased concentration of oxygen supplied to the engine can be compensated. In one example, the amount of fuel by which the fuel supply is reduced compared to the amount of fuel with a higher reactivity supplied in a steady state can be empirically determined and stored in a table indexed based on engine speed and engine torque. In an alternative example, the amount of fuel with a greater reactivity by which the fuel supply of a steady state fuel charge is reduced may be based on the difference between the desired and actual concentrations of oxygen supplied to the engine (for example, based on an error in the concentration of oxygen supplied to the engine). The amount of fuel by which the fuel supply is reduced compared to the quantity of fuel with a higher reactivity supplied in a steady state can be indexed based on the error in the concentration of oxygen supplied to the engine. The amount of fuel with greater reactivity at steady state is corrected by subtracting the amount by which the fuel supply was reduced from the amount of fuel supply with greater reactivity at steady state. Thus, the concentrations of oxygen supplied to the engine under transient conditions can be compensated under conditions when two types of fuel with different reactivity are injected into the engine.

In some examples, the number and distribution of moments of fuel injection with greater reactivity can also be adjusted in response to the temperature of the oxygen supplied to the engine. For example, if the temperature of the oxygen supplied to the engine increases, the amount of fuel with greater reactivity can be reduced, while the amount of fuel with less reactivity can be increased compared to the quantities of fuel with more and less reactivity when steady.

At 1010, method 1000 biases the distribution of fuel injection times under current engine operating conditions compared to steady state operating conditions. The distribution of moments of fuel injection can be shifted to the side of delay or lead by adjusting the distribution of moments of the beginning of fuel injection. The lag of the moment of injection of fuel for fuel with greater reactivity can be determined empirically and stored in the table in order to extract this value later. In one example, a fuel injection timing chart may be indexed based on engine speed and torque. In addition, in some examples, an error in the concentration of oxygen supplied to the engine may be the basis for controlling the moments of fuel injection with greater reactivity. For example, a table containing the values of the delay in the moments of fuel injection can be indexed based on the error in the concentration of oxygen supplied to the engine, and the distribution of moments of fuel injection can be shifted in the direction of delay by the value extracted from this table.

At 1012, method 1000 increases the amount of fuel injected into the engine with less reactivity compared to the amount of fuel with less reactivity injected into the engine under steady-state engine conditions. In one example, the amount of fuel by which the value of the injected fuel with less reactivity has been increased can be based on the amount of fuel by which the value of the fuel with more reactivity injected when steady is reduced. In particular, the energy intensity of the fuel is determined, the amount of which was subtracted from the amount of injected fuel with greater reactivity compared to the amount of fuel with greater reactivity injected at a steady state, and the amount of injected fuel with less reactivity increases by the amount of fuel having the same energy intensity that and the amount of fuel with high reactivity, which was reduced by the amount of fuel with greater reactivity injected at steady state. Thus, the total energy intensity of the injected fuel is adjusted so as to match the required engine torque. Alternatively, an empirically determined amount of fuel can be determined by indexing a table or a function to increase the amount of injected fuel and adding the amount of fuel contained in the table to the amount of fuel with less reactivity injected when steady. After increasing the amount of fuel with less reactivity, method 1000 proceeds to step 1014.

It should be noted that in some examples, the total amount of fuel injected into the engine is based on the desired level of engine torque. For example, a situation may arise in which it is desirable to provide 80% of the desired magnitude of the engine torque with a fuel with a higher reactivity and provide 20% of the desired magnitude of the engine torque with a fuel with a lower reactivity. Therefore, the desired torque can be increased by 80% to determine the amount of energy that should be provided with fuel with greater reactivity. Accordingly, a fuel pulse with a higher reactivity can be transmitted to the engine, which corresponds to the amount of fuel with a higher reactivity necessary to provide the requested energy. The amount of fuel with less reactivity can be determined in a similar way.

On the other hand, if the answer is “yes” at step 1006, the method 1000 proceeds to step 1018, where the method 1000 increases the amount of fuel injected into the engine with greater reactivity relative to the amount of fuel with greater reactivity injected into the engine under steady state operating conditions . Additional amounts of fuel with greater reactivity can be injected into the engine by increasing the fuel pressure and / or by increasing the length of time that the nozzle is open. By increasing the amount of fuel injected into the engine when the concentration of oxygen supplied to the engine is positive, the concentration of oxygen supplied to the engine can be compensated by increasing the amount of fuel injected into the engine with greater reactivity. In one example, the amount of additional fuel added to the amount of fuel injected in a steady state can be empirically determined and stored in a table indexed based on engine speed and engine torque. In an alternative example, the amount of additional fuel added to the amount of fuel injected in a steady state may be based on the difference between the desired and actual concentrations of oxygen supplied to the engine. An amount additional to the amount of fuel with greater reactivity injected in a steady state can be indexed based on an error in the concentration of oxygen supplied to the engine. The amount of fuel with greater reactivity at steady state is adjusted by adding the amount of fuel added to the amount of fuel injected in the steady state. Thus, the concentrations of oxygen supplied to the engine under transient conditions can be compensated under conditions when two types of fuel with different reactivity are injected into the engine.

At 1020, method 1000 shifts ahead of the distribution of fuel injection times under current engine operating conditions compared to steady state operating conditions. The magnitude of the shift in the direction of advancing the moments of fuel injection with greater reactivity can be determined empirically and stored in the table in order to extract this value later. In one example, a fuel injection timing chart may be indexed based on engine speed and torque. In addition, in some examples, the error in the concentration of oxygen supplied to the engine may be the basis for regulating the distribution of moments of injection of more jet fuel. For example, a table containing shift values ahead of the distribution of moments of fuel injection can be indexed based on the value of the error in the concentration of oxygen supplied to the engine, and the distribution of moments of fuel injection can be shifted ahead of the curve by the value extracted from the table.

At 1022, method 1000 reduces the amount of fuel injected into the engine with less reactivity. In one example, the amount of fuel by which the fuel supply with less reactivity has been reduced can be based on the amount of fuel by which the amount of fuel with more reactivity increased in steady state conditions has been increased. In particular, the energy intensity of the fuel added to the amount of more jet fuel injected at a steady state is determined, and the amount of injected fuel with less reactivity is reduced by the amount of fuel having the same energy intensity as the amount of fuel added to the amount of more jet fuel injected at steady state. Thus, the total energy consumption of the injected fuel is adjusted to match the required engine torque. Alternatively, the amount of fuel determined empirically can be determined by indexing the table or the function of decreasing the amount of fuel injected and subtracting the amount of fuel contained in the table from the amount of fuel with less reactivity injected at steady state. Method 1000 proceeds to step 1014 after reducing the amount of fuel with less reactivity.

At 1014, a distribution of fuel injection times with less reactivity can be adjusted. If fuel with less reactivity is injected directly into the engine cylinder, the distribution of the moments of the start and end of the injection can be adjusted. For example, the distribution of the moments of the beginning and end of injection can be shifted in the direction of advance or delay relative to the position of the crankshaft of the engine. The method 1000 proceeds to step 1016 after adjusting the distribution of moments of fuel injection with less reactivity.

At 1016, method 1000 determines whether a change in the desired boost level occurs. In one example, a change in boost can be determined based on a change in position of the bypass damper of the turbocharger or guide vane. In some examples, the threshold value for changing the desired boost should be exceeded before proceeding to step 1024. If method 1000 determines whether there is a change in the desired boost, then method 1000 proceeds to step 1024. Otherwise, method 1000 ends.

At step 1024, method 1000 determines whether the desired boost level is increased. If it rises, then method 1000 proceeds to step 1026. Otherwise, method 1000 proceeds to step 1034.

The method 1000, which reduced the amount of injected fuel with greater reactivity in step 1026, shifts the timing of the injection of fuel with greater reactivity in step 1028 and increases the amount of fuel with greater reactivity in step 1030, as described in steps 1008-1012. However, in steps 1026-1030, method 1000 controls both the number and distribution of moments of fuel injection with greater reactivity and the number and distribution of moments of fuel injection with less reactivity in response to a change in boost level rather than a change in the concentration of oxygen supplied to the engine . Thus, the method 1000 provides for individual adjustment of the number and distribution of moments of fuel injection with greater reactivity based on changes in the level of boost. In addition, the method 1000 provides for individual adjustment of the number and distribution of moments of fuel injection with less reactivity based on changes in the level of boost.

Similarly, method 1000 increases the amount of injected fuel with greater reactivity in step 1034, shifts the timing of the injection of fuel with more reactivity in step 1036, and reduces the amount of fuel with less reactivity in step 1038, as described in steps 1018-1022. However, in steps 1034-1038, method 1000 controls both the number and distribution of fuel injection moments with greater reactivity, and the number and distribution of fuel injection moments with less reactivity in response to a change in boost level rather than a change in the concentration of oxygen supplied to the engine. Thus, the method 1000 provides for individual adjustment of the number and distribution of moments of fuel injection with greater reactivity based on changes in the level of boost. In addition, the method 1000 provides for individual adjustment of the number and distribution of moments of fuel injection with less reactivity based on changes in the level of boost.

At 1032, the timing of fuel injection with less reactivity can be adjusted. As described above with respect to step 1014, if fuel with less reactivity is injected directly into the engine cylinders, the distribution of the moments of the start and end of the injection can be adjusted. For example, the distribution of the moments of the beginning and end of injection can be shifted in the direction of advance or delay relative to the position of the crankshaft of the engine. The method 1000 proceeds to step 1034 after the distribution of moments of fuel injection with less reactivity is adjusted.

At 1034, method 1000 outputs data on adjusting the distribution of injection times and the amount of fuel supplied to injectors that inject fuel with greater and less reactivity. The adjustment of fuel injectors delivering fuel with greater and less reactivity is carried out in such a way that both types of injectors operate in accordance with updated fuel quantities and distribution of injection moments during the same engine cycle. Thus, the quantities and distribution of moments of fuel injection with greater and less reactivity can be adjusted to compensate for delays in the engine air intake system.

Thus, the method of FIG. 10 and 11 provides the operating sequences illustrated in FIG. 2-9 and an engine operating method, including: increasing an amount of a first type of fuel with a first reactivity injected into a cylinder at a transition exceeding a threshold value in response to an error in the concentration of oxygen supplied to the engine; a decrease in the amount of a second type of fuel with a second reactivity injected into the cylinder upon transition, in response to an error in the concentration of oxygen supplied to the engine; and ignition of the first and second types of fuel from compression in the cylinder. Thus, the injection of two types of fuel can compensate for errors in the concentration of oxygen supplied to the engine, which can occur from engine torque disturbances, EGR disturbances, engine air flow disturbances. The method of operating the engine also includes a shift in advance of the distribution of moments of injection of the first fuel during the transition, in which the amount of the first fuel increases during cylinder cycles between the beginning and end of the transition, and in which the amount of the second fuel decreases during cylinder cycles between the beginning and end transition. The method of operating the engine provides for cases where the transition is a change in engine torque, when the number and distribution of the moments of injection of the first fuel at a steady state are regulated, and when the amount of the second fuel is regulated. An engine operation method involves cases where an error in the concentration of oxygen supplied to the engine indicates an excess of the desired concentration of oxygen supplied to the engine in a steady state and when the first reactivity is greater than the second reactivity. The engine operation method also includes controlling the amounts of the first fuel and the second fuel in response to a boost error. An engine operation method involves cases where the error of oxygen supplied to the engine increases in response to an EGR valve position. The engine operation method also includes controlling the amount of the first fuel in response to the difference between the desired boost value and the actual boost value. A method of operating an engine involves cases where the desired boost value is the boost value under steady-state conditions of the engine, and when the amount of oxygen supplied to the engine is the concentration of oxygen contained in the engine cylinders before combustion in the cylinder during the cylinder cycle, when the amount of the first fuel increases in response to an error in the concentration of oxygen supplied to the engine.

In addition, the method of FIG. 10 and 11 provides for the sequence of FIG. 2-9 and a method of operating an engine, comprising: increasing the amount of the first fuel in a steady state, scheduled for injection between the start and end of the transition, the first fuel having a first reactivity; reducing the amount of the second fuel in steady state, scheduled for injection between the beginning and end of the transition, the second fuel having a second reactivity; and compression ignition of the first and second fuel in the air-fuel mixture. The method of operating the engine also includes a shift in advance of the distribution of moments of injection of the first fuel during the transition. The engine operation method also includes cases where the transition is a change in engine torque, and when the quantity and distribution of injection times of the first fuel at steady state and the quantity and distribution of injection moments of the second fuel at steady state are adjusted to provide the requested engine torque. The engine operation method also includes cases where the amount of the first fuel in steady state, scheduled for injection between the start and end of the transition, is the amount of fuel based on the engine speed and engine torque in steady state. The engine operation method also includes controlling the amount of the first fuel in response to the difference between the desired EGR value and the actual EGR value. The engine operation method also includes cases where the desired EGR value is the desired EGR value under the conditions of engine operation at steady state. The engine operation method also includes controlling the amount of the first fuel in response to the difference between the desired boost value, the actual boost value. Thus, the phasing of combustion can be adjusted to compensate for changes in EGR, the amount of engine air and boost above a threshold value. The engine operation method also includes cases where the desired boost value is the boost amount under steady state engine conditions.

In another example, the method of FIG. 10 and 11 is a method of operating an engine, including: transition from a first operating state of an engine to a second operating state; regulation of the number and distribution of moments of injection of the first fuel with the first reactivity injected into the cylinder to a level that is greater or less than the level planned for operating conditions in a stable state between the first and second operating states of the engine; and adjusting the amount of the second fuel with the second reactivity injected into the cylinder to a level that is greater or less than the level planned for the steady state operation between the first and second operating states of the engine, the direction of the change in the amount of the second injected fuel is opposite to the direction of the change in the amount of the first injected fuel , and the second reactivity is less than the first reactivity. The engine operation method provides for cases when the direction of the change in the amount of the second fuel is a decrease, and the direction of the change in the amount of the second fuel is an increase. The engine operation method also includes cases where the direction of the change in the amount of the second fuel is an increase, and the direction of the change in the amount of the second fuel is a decrease. The engine operation method also includes cases where the first fuel with the first reactivity is diesel fuel and the second fuel with the second reactivity is gasoline or alcohol. The engine operation method also includes cases where the regulation of the first fuel with the first reactivity is based on an EGR error. The engine operation method involves cases where the regulation of the amount of the first fuel with the first reactivity is based on a boost error.

It will be understood by those skilled in the art that the method described in FIG. 10 and 11 can reproduce one or more execution strategies, for example, event control, interrupt control, multitasking, multithreading, and others. In this regard, various steps or functions can be performed in the presented sequence, in parallel, and in some cases can be skipped. Also, the execution order does not have to be the same as it is shown; it is given for visual representation and description of the process. Also, experts in this field can see that some steps, methods or functions may be repeated depending on the option used.

Specialists in this field should bear in mind that there are various options and modifications of the presented method without going beyond the scope of the invention. For example, it is possible to use the presented method for engines with a single cylinder, I2, I3, I4, I5, V6, V8, V10, V12 and V16, working on natural gas, gasoline, diesel or other alternative fuels.

Claims (19)

1. The method of operation of the engine, including:
an increase in the amount of first fuel with first reactivity injected into the cylinder during a transition exceeding a threshold value in response to an error in the concentration of oxygen supplied to the engine;
a decrease in the amount of a second fuel with a second reactivity injected into the cylinder during a transition exceeding a threshold value in response to an error in the concentration of oxygen supplied to the engine; and
compression ignition of the first and second fuel in the cylinder. 2. The method according to claim 1, further comprising shifting in advance of the injection moment of the first fuel during the transition, the amount of the first fuel increasing during cylinder cycles between the beginning and the end of the transition, and the amount of the second fuel decreasing during the cylinder cycles between the beginning and completion of the transition. 3. The method according to p. 2, in which the transition is a change in engine torque, which regulate the number and distribution of moments of injection of the first fuel at a steady state and in which regulate the amount of the second fuel. 4. The method according to claim 1, in which the error in the concentration of oxygen supplied to the engine indicates an excess of the desired concentration of oxygen supplied to the engine when the state is stable, and in which the first reactivity is greater than the second reactivity. 5. The method according to p. 1, in which additionally carry out the regulation of the quantities of the first fuel and the second fuel in response to a boost error. 6. The method according to claim 1, in which the error in the concentration of oxygen supplied to the engine increases in response to a change in the air mass flow in the engine. 7. The method according to p. 1, in which additionally regulate the amount of the first fuel in response to the difference between the desired boost value and the actual boost value. 8. The method according to p. 7, in which the desired boost value is the boost value under steady-state conditions of the engine and in which the amount of oxygen supplied to the engine is the oxygen concentration in the engine cylinders before combustion in the cylinders during the cylinder cycle, where the first fuel is increased in response to an error in the oxygen supplied to the engine. 9. A method of operating an engine in which:
carry out the transition from the first operating state of the engine to the second operating state of the engine;
regulate the number and distribution of moments of injection of the first fuel injected into the cylinder with the first reactivity to a level that is greater than or less than the level planned for stable operating conditions between the first and second operating states of the engine; and
regulate the amount of second fuel injected into the cylinder with a second reactivity to a level that is greater or less than the level planned for stable operating conditions between the first and second operating states of the engine, and the direction of change of the amount of the second injected fuel is opposite to the direction of change of the amount of the first injected fuel, and the second reactivity is less than the first reactivity,
moreover, the amount of the first fuel with the first reactivity is adjusted based on the boost error 10. The method according to p. 9, in which the amount of the second fuel is reduced, and the amount of the first fuel is increased. 11. The method according to p. 9, in which the amount of the second fuel is increased, and the amount of the first fuel is reduced. 12. The method according to claim 9, in which the first fuel with the first reactivity is diesel fuel, and the second fuel with the second reactivity is gasoline or alcohol. 13. The method according to p. 9, in which the amount of the first fuel with the first reactivity is adjusted based on an error in the amount of air supplied to the engine. 14. The engine system, including:
a diesel fuel injector configured to directly inject diesel into the engine cylinder, the diesel fuel having a first reactivity index;
a second fuel injector configured to inject a second fuel into the engine cylinder, the second fuel having a second reactivity index; and
a controller containing instructions for increasing the amount of diesel fuel planned for injection at a steady state based on an error in the amount of air supplied to the engine during a transition in the working state of the engine, as well as additional instructions for reducing the amount of second fuel at a steady state scheduled for injection based on errors in the amount of air supplied to the engine during the specified transition. 15. The engine system according to claim 14, in which the controller further comprises instructions for increasing the amount of diesel fuel planned for injection at a steady state based on a boost error during a transition in an operational state of the engine. 16. The engine system of claim 15, wherein the controller further comprises instructions for decreasing the amount of the second fuel planned for injection in a steady state based on a boost error during a transition in an operational state of the engine. 17. The engine system of claim 15, wherein the second fuel injector is an injector for injection into the inlet channel. 18. The engine system of claim 15, wherein the second fuel injector is a fuel injector for direct injection, wherein the second fuel is gasoline or alcohol, and the distribution of the timing of the start of injection of the second fuel can be adjusted in response to said transition. 19. The engine system of claim 15, wherein the controller further comprises instructions for decreasing the amount of diesel fuel scheduled for injection in a steady state based on an error in the amount of air supplied to the engine, as well as additional instructions for adjusting the amount of diesel fuel scheduled for injection in a steady state based on the temperature of the air supplied to the engine.

Images