Control system for internal combustion engines
The control system for internal combustion engines addresses the lack of novel motoring operations by moving gas between cylinders and using a heating device to warm up the engine, enhancing fuel atomization and catalyst activation.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- MITSUBISHI MOTORS CORP
- Filing Date
- 2023-02-15
- Publication Date
- 2026-05-19
AI Technical Summary
Existing control systems for internal combustion engines lack the capability to perform novel motoring operations beyond catalyst warming.
A control system for an internal combustion engine incorporating a first and second cylinder, a rotary electric machine, and a control device that enables motoring operations by moving gas between cylinders and utilizing a heating device to warm up the engine.
The system effectively warms up the internal combustion engine through novel motoring operations, improving fuel atomization, reducing emissions, and optimizing catalyst activation temperature.
Smart Images
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Abstract
Description
Technical Field
[0001] The present disclosure relates to a control system for an internal combustion engine.
Background Art
[0002] Conventionally, a control system for an internal combustion engine having a motor and an internal combustion engine and performing a motoring operation for driving the internal combustion engine by the motor is known (see, for example, Patent Document 1). The control system for the internal combustion engine of Patent Document 1 performs a motoring operation for warming up an adsorption catalyst by reciprocating air between the adsorption catalyst and an electric heater.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] Motoring can be used not only for warming up the catalyst.
[0005] An object of the present disclosure is to provide a control system for an internal combustion engine capable of realizing a new motoring operation.
Means for Solving the Problems
[0006] The control system for an internal combustion engine according to the present disclosure includes an internal combustion engine having a first cylinder and a second cylinder different from the first cylinder, a rotary electric machine capable of driving the internal combustion engine, and a control device that controls the internal combustion engine and the rotary electric machine. The control device drives the internal combustion engine by the rotary electric machine and executes a first motoring control for moving the gas in the first cylinder from the first cylinder to the second cylinder.
[0007] According to this internal combustion engine control system, the internal combustion engine can be warmed up by performing a first motoring operation that moves the gas from the first cylinder to the second cylinder. [Effects of the Invention]
[0008] According to this disclosure, a control system for an internal combustion engine that can realize novel motoring can be provided. [Brief explanation of the drawing]
[0009] [Figure 1] A system diagram of an electric vehicle according to one embodiment of the present disclosure. [Figure 2] A system diagram of an internal combustion engine according to one embodiment of the present disclosure. [Figure 3] A diagram showing the cam profiles of a firing cam and a motoring cam according to one embodiment of the present disclosure. [Figure 4] A diagram showing the cam operation in each stroke by a motor cam according to one embodiment of the present disclosure. [Figure 5] A diagram showing the gas flow during heating motoring according to one embodiment of the present disclosure. [Figure 6] A diagram showing the gas flow during heat retention motoring according to one embodiment of the present disclosure. [Figure 7] A flowchart illustrating a control procedure performed by a control device according to one embodiment of the present disclosure. [Figure 8] A diagram showing the gas flow during heating motoring according to another embodiment of the present disclosure. [Modes for carrying out the invention]
[0010] Hereinafter, one embodiment of this disclosure will be described with reference to the drawings.
[0011] As shown in Figure 1, the control system 3 for the internal combustion engine 1 of this embodiment is mounted on an electric vehicle C that drives the wheels C1 using the internal combustion engine 1 and the motor (FrM) 2 as power sources. However, the internal combustion engine 1 may also be mounted on a vehicle that uses only the internal combustion engine 1 as a power source.
[0012] The electric vehicle C comprises an internal combustion engine 1, a motor 2, a generator (GEN: an example of a rotating electric machine) 4, a drive battery (BT: an example of a battery) 6 including a secondary battery such as a lithium-ion battery, and a transaxle 8. The generator 4 is connected to the internal combustion engine 1 and can drive the internal combustion engine 1. While the vehicle is powered by electricity from the drive battery 6, the generator 4 performs motoring to drive the internal combustion engine 1. On the other hand, the generator 4 generates electricity when driven by the internal combustion engine 1 while the internal combustion engine 1 is running. Therefore, the generator 4 is a motor-generator capable of both powering and generating electricity. The transaxle 8 has multiple gears and a clutch 8a. The internal combustion engine 1 is connected to the generator 4 and the axle 10 via the transaxle 8. When the clutch 8a is open, power transmission between the internal combustion engine 1 and the axle 10 is interrupted, and when the clutch 8a is engaged, power from the internal combustion engine 1 is transmitted to the axle 10. The motor 2 is connected to the axle 10 via the transaxle 8. The electric vehicle C may also have a vehicle control device (an example of a control device) 12, an engine control device 14 that controls the internal combustion engine 1, an accelerator pedal 16 operated by the user of the electric vehicle C, an inverter 18 that controls the motor 2 and the generator 4, and a charging button (not shown). In this embodiment, the electric vehicle C is a plug-in hybrid vehicle (PHEV) having a charger 20 that can be connected to an external power source and a power supply device 22 that can supply power from the drive battery 6 to external devices such as home appliances. However, the electric vehicle C may be a hybrid vehicle that does not have such devices.
[0013] The electric vehicle C of this embodiment has various modes, including EV mode, series mode, parallel mode, and charging mode. In EV mode, the electric vehicle C drives the motor 2 with power from the drive battery 6. In series mode, the electric vehicle C drives the generator 4 with the internal combustion engine 1, and uses the power generated by the generator 4 to drive the motor 2. In parallel mode, the electric vehicle C engages the clutch 8a and uses the power of the internal combustion engine 1 to drive the axle 10. In charging mode, the electric vehicle C drives the generator 4 with the internal combustion engine 1, and stores the power generated by the generator 4 in the drive battery 6. Depending on the state of the accelerator pedal 16 and the operation state of the charging button, the vehicle control device 12 switches between modes, controls the motor 2 and generator 4 via the inverter 18, and causes the engine control device 14 to control the internal combustion engine 1.
[0014] As shown in Figure 2, the internal combustion engine 1 comprises a port injection valve 30, a spark plug 32, an intake cam 34, an intake valve 35, an exhaust cam 36, an exhaust valve 37, a heating device 38, a catalyst 40, a throttle 42, and a temperature sensor 44. In this embodiment, the internal combustion engine 1 is a gasoline engine that ignites a fuel-air mixture injected from the port injection valve 30 with intake air using a spark plug 32. Also, as shown in Figures 1 and 2, in this embodiment, the internal combustion engine 1 has four cylinders 50, with two intake valves 35 and two exhaust valves 37 arranged in each cylinder. The temperature sensor 44 is a sensor that detects the operating temperature of the heating device 38 by detecting the temperature of the catalyst 40.
[0015] In this embodiment, the intake cam 34 and exhaust cam 36 each have a firing cam and a motoring cam. As shown in Figure 2, the intake cam 34 has an intake cam switching device 34a that switches between the intake firing cam and the intake motoring cam of the intake cam 34. The exhaust cam 36 has an exhaust cam switching device 36a that switches between the exhaust firing cam and the exhaust motoring cam of the exhaust cam 36.
[0016] As shown in FIG. 3, the firing cam opens and closes the intake valve 35 and the exhaust valve 37 in the order of the intake stroke, compression stroke, expansion stroke, and exhaust stroke of the internal combustion engine 1. Specifically, as shown in the cam profiles of the intake firing cam and the exhaust firing cam indicated by the broken lines in FIG. 3, the firing cam opens and closes the intake valve 35 during the intake stroke. The firing cam closes the intake valve 35 and the exhaust valve 37 by the intake firing cam and the exhaust firing cam during the compression stroke and the expansion stroke. The firing cam opens and closes the exhaust valve 37 by the exhaust firing cam during the exhaust stroke. Thus, the firing cam is a cam used to transition the internal combustion engine 1 in the order of the intake stroke, compression stroke, expansion stroke, and exhaust stroke and to burn the air-fuel mixture.
[0017] The motoring cam is a cam for realizing warm-up motoring control (an example of the first motoring control) and temperature-rising motoring control (an example of the second motoring control). The motoring cam sucks the gas in the exhaust passage 46 (the air in the exhaust passage 46 in this embodiment) into the cylinder 50 by opening the exhaust valve 37 at the timing corresponding to the intake stroke or the expansion stroke (the timing when the piston 48 in FIG. 2 descends). The motoring cam returns the gas in the cylinder 50 to the exhaust passage 46 by opening the exhaust valve 37 at the timing corresponding to the exhaust stroke or the compression stroke (the timing when the piston 48 in FIG. 2 ascends).
[0018] Specifically, as shown in the profiles of the intake motoring cam and the exhaust motoring cam indicated by the solid lines in FIG. 3, the motoring cam opens the exhaust valve 37 using the exhaust motoring cam from the intake stroke to the compression stroke. The motoring cam similarly opens the exhaust valve 37 using the exhaust motoring cam from the expansion stroke to the exhaust stroke. During this period, the motoring cam closes the intake valve 35 in the entire stroke using the intake motoring cam. That is, the exhaust motoring cam is an elliptical cam. The intake motoring cam is a circular cam without a cam peak.
[0019] Also, when the internal combustion engine 1 has a plurality of cylinders 50, the motoring cam can prevent the gas discharged from the cylinder 50 from being sucked into another cylinder during warm-up motoring control. Specifically, as shown in FIG. 4, the motoring cam can keep the exhaust valve 37 closed by executing a cylinder cut-off operation that partially stops the operation of the exhaust motoring cam.
[0020] The solid line in FIG. 4 indicates the operation of the exhaust motoring cam during warm-up motoring control. As shown by the solid line in FIG. 4, in order to prevent the gas in the intake passage 49 (see FIG. 2) from flowing into the cylinder 50 during warm-up motoring, the motoring cam keeps some of the cylinders 50 in a state where the exhaust valve 37 is not opened in addition to the intake valve 35, and performs cylinder cut-off.
[0021] As shown by the solid line in FIG. 4 and FIG. 5, for example, when the piston 48 of the first cylinder 50a is descending, the intake valve 35 of the first cylinder 50a is closed and the exhaust valve 37 is opened (see the expansion stroke and exhaust stroke of the first cylinder in FIG. 4). Similarly, since the piston 48 of the fourth cylinder 50d is also descending, the intake valve 35 of the fourth cylinder 50d is closed and the exhaust valve 37 is opened (see the intake stroke and compression stroke of the fourth cylinder in FIG. 4). On the other hand, the motoring cam puts the second cylinder 50b adjacent to the first cylinder 50a into a cylinder cut-off state where the intake valve 35 and the exhaust valve 37 are not opened (see the second cylinder in FIG. 4). The motoring cam also puts the third cylinder 50c adjacent to the fourth cylinder 50d into a cylinder cut-off state in the same way (see the third cylinder in FIG. 4). As shown in FIG. 5, by operating in this way, the motoring cam allows the first cylinder 50a and the fourth cylinder 50d to take in the gas in the exhaust passage 46 and then discharge it back into the exhaust passage 46, causing the gas in the exhaust passage 46 to reciprocate between the cylinder 50 and the heating device 38. During warm-up motoring control, the motoring cam also causes the gas to reciprocate between the cylinder 50 and the heating device 38 for the second cylinder 50b and the third cylinder 50c in the same way when they are not in cylinder cut-off.
[0022] The dashed line in Figure 4 shows the operation of the exhaust motoring cam during thermal motoring control. When there are four cylinders 50, as shown by the dashed line in Figure 4 and in Figure 6, the exhaust valve 37 of the second cylinder 50b opens while gas is being discharged from cylinder 50 in the first cylinder 50a. As shown in Figure 6, the motoring cam, by performing this operation, directs the gas from the first cylinder 50a to the second cylinder 50b. The motoring cam similarly directs the gas from the fourth cylinder 50d to the third cylinder 50c. The motoring cam also directs the gas from the second cylinder 50b to the first cylinder 50a. The motoring cam similarly directs the gas from the third cylinder 50c to the fourth cylinder 50d. In this way, the motoring cam moves the gas from one cylinder 50 to another cylinder 50 during thermal motoring control.
[0023] As shown in Figure 2, the heating device 38 is a device that heats the gas in the exhaust passage 46. In this embodiment, the heating device 38 is an electric heater that heats the gas using an electric heating element. The heating device 38 is electrically connected to the low-voltage battery 52. The low-voltage battery 52 is supplied with power that has been stepped down from the power of the drive battery 6.
[0024] In the temperature rise motoring control, the heating device 38 heats the gas. In the temperature rise motoring control, the gas heated by the heating device 38 moves back and forth between the exhaust passage 46 and the heating device 38. As a result, the heated gas is supplied from the first cylinder 50a to the fourth cylinder 50d.
[0025] The vehicle control device 12 is electrically connected to the generator 4 via the inverter 18 and controls the generator 4. The vehicle control device 12 also sends instructions to the engine control device 14, such as at least heat retention motoring control and heat rise motoring control, to cause the engine control device 14 to control the internal combustion engine 1. The vehicle control device 12 is an ECU (Electronic Control Unit) composed of a microcomputer including an arithmetic unit, memory, and input / output buffers. The vehicle control device 12 performs various controls on the electric vehicle C based on maps and programs stored in memory.
[0026] Furthermore, the vehicle control device 12 is electrically connected to the control unit (not shown) of the drive battery 6, and can obtain information such as the state of charge (SOC) and battery temperature of the drive battery 6 from the control unit of the drive battery 6.
[0027] The engine control device 14 is electrically connected to various devices of the internal combustion engine 1 and is a control device that controls the internal combustion engine 1. In practice, the engine control device 14 is an ECU (Electronic Control Unit) composed of a microcomputer including an arithmetic unit, memory, and input / output buffers. The engine control device 14 performs various controls on the internal combustion engine 1 based on maps and programs stored in memory. Note that the control of the internal combustion engine 1 may also be performed by the vehicle control device 12 in addition to the engine control device 14.
[0028] When the engine control device 14 receives an instruction from the vehicle control device 12 for either heat retention motoring control or heat rise motoring control, if the internal combustion engine 1 is in a firing state, it stops firing (stops fuel injection and ignition) and switches to the motoring cam. Also, when the engine control device 14 receives an instruction for heat rise motoring control, it activates the heating device 38.
[0029] Next, the control procedure performed by the vehicle control device 12 will be explained using the flowchart in Figure 7. For example, when the conditions for starting the internal combustion engine 1 are met, or when the conditions for stopping or cutting fuel for the internal combustion engine 1 are met, the vehicle control device 12 determines that the conditions for performing motoring have been met and starts the control procedure.
[0030] In step S1, the vehicle control device 12 obtains the temperature T of the internal combustion engine 1. In this embodiment, the temperature T of the internal combustion engine is the ambient temperature of the electric vehicle C. However, the temperature T of the internal combustion engine 1 can be obtained using various values, such as the water temperature of the internal combustion engine 1 or the temperature of the catalyst 40 obtained by the temperature sensor 44. Once the vehicle control device 12 obtains the temperature T of the internal combustion engine 1, it proceeds to step S2.
[0031] In step S2, the vehicle control device 12 determines whether or not it is an extremely cold start. In this embodiment, if the temperature T obtained in step S1 is the ambient temperature, the vehicle control device 12 determines that it is an extremely cold start if it is minus 10 degrees Celsius or lower. However, the vehicle control device 12 may also determine whether or not it is an extremely cold start based on the water temperature or the like. If the vehicle control device 12 determines that it is an extremely cold start (step S2 YES), it proceeds to step S3.
[0032] In step S3, the vehicle control device 12 obtains the motoring time. The motoring time may be calculated by the vehicle control device 12 based on, for example, the relationship between the output of the generator 4 under the heat retention motoring control during extremely cold startup (the power consumed by the motoring of the internal combustion engine 1 by the generator 4) and the state of charge (SOC) of the drive battery 6, or based on the power that the drive battery 6 can output. Once the vehicle control device 12 obtains the motoring time, it proceeds to step S4.
[0033] In step S4, the vehicle control device 12 performs heat retention motoring control. Specifically, when the vehicle control device 12 starts heat retention motoring control, it powers the generator 4 and motors the internal combustion engine 1. The vehicle control device 12 also sends a signal to the engine control device 14 to perform heat retention motoring. Furthermore, the engine control device 14 controls the intake cam switching device 34a and the exhaust cam switching device 36a and switches to the motoring cam. When the electric vehicle C is running, the vehicle control device 12 lowers the rotational speed of the internal combustion engine 1 due to heat retention motoring control (hereinafter referred to as motoring rotational speed) compared to when the electric vehicle C is stopped. Specifically, when the electric vehicle C is running, the motoring rotational speed may be set to the initial combustion range of the internal combustion engine 1 (for example, around 600 rpm), and when the electric vehicle C is stopped, it may be set to the idle range (for example, around 700 rpm). This can suppress energy consumption by the generator 4. After the vehicle control device 12 performs heat retention motoring control, it proceeds to step S5.
[0034] In step S5, the vehicle control device 12 determines whether or not it is possible to perform temperature-boosting motoring control. The vehicle control device 12 may determine whether or not it is possible to perform temperature-boosting motoring control based on the load on the generator 4 or the power that the drive battery 6 can output. Alternatively, the vehicle control device 12 may determine that temperature-boosting motoring is possible when the internal combustion engine 1 has been warmed up by the heat-retention motoring control and the friction of the internal combustion engine 1 has decreased. If the vehicle control device 12 determines that temperature-boosting motoring is possible (step S5 YES), it proceeds to step S6.
[0035] In step S6, the vehicle control device 12 performs temperature-boosting motoring control. Specifically, it turns on the heating device 38 and causes the motoring cam to deactivate the cylinder, supplying gas heated by the heating device 38 to the cylinder 50. After performing temperature-boosting motoring control, the vehicle control device 12 proceeds to step S7.
[0036] If the vehicle control device 12 determines in step S5 that it is not possible to perform the temperature rise motoring control (step S5 NO), the vehicle control device 12 proceeds to step S7 and skips the temperature rise motoring control.
[0037] In step S7, the vehicle control device 12 determines whether or not to terminate motoring. The vehicle control device 12 may decide to terminate motoring if, for example, it determines that the motoring time has elapsed. In addition, the vehicle control device 12 may decide to terminate motoring if it determines that the water temperature of the internal combustion engine 1 has reached a temperature sufficient for the fuel in cylinder 50 to vaporize (for example, 20 degrees Celsius or higher). If the vehicle control device 12 decides to terminate motoring (step S7 YES), it terminates the control procedure. In the case of extremely cold start and cold start, the vehicle control device 12 starts the internal combustion engine 1 after terminating the control procedure. In the case of fuel cut, the vehicle control device 12 restarts fuel injection and ignition after terminating the control procedure.
[0038] If, in step S7, the vehicle control device 12 determines that it will not terminate motoring (step S7 NO), the process proceeds to step S2.
[0039] If the vehicle control device 12 determines in step S2 that it is not an extremely cold start (step S2 NO), the vehicle control device 12 proceeds to step S8. In step S8, the vehicle control device 12 determines whether or not it is a cold start. In this embodiment, the vehicle control device 12 determines that it is a cold start if the ambient temperature obtained in step S1 is greater than minus 10 degrees Celsius and 10 degrees Celsius or less. Also, the vehicle control device 12 determines that it is a cold start if the temperature of the catalyst 40 obtained by the temperature sensor 44 is below the activation temperature of the catalyst 40. However, the vehicle control device 12 may also determine whether or not it is a cold start based on the water temperature or the like. If the vehicle control device 12 determines that it is a cold start (step S8 YES), it proceeds to step S9.
[0040] In step S9, the vehicle control device 12 obtains the motoring time. The motoring time may be calculated by the vehicle control device 12 based on, for example, the relationship between the output of the generator 4 under temperature rise motoring control during cold start and the state of charge (SOC) of the drive battery 6, or the power that the drive battery 6 can output. At this time, the power consumed by the heating device 38 may also be taken into consideration. Once the vehicle control device 12 obtains the motoring time, it proceeds to step S10.
[0041] In step S10, the vehicle control device 12 performs temperature-boosting motoring control. Specifically, when the vehicle control device 12 starts temperature-boosting motoring control, it powers the generator 4. The vehicle control device 12 also turns on the heating device 38. Furthermore, the vehicle control device 12 sends a signal to the engine control device 14 to perform temperature-boosting motoring. The engine control device 14 then controls the intake cam switching device 34a and the exhaust cam switching device 36a to switch to the motoring cam. The engine control device 14 controls the motoring cam to perform cylinder deactivation. Once the vehicle control device 12 has performed temperature-boosting motoring control, it proceeds to step S11.
[0042] In step S11, the vehicle control device 12 determines whether or not it is possible to perform heat retention motoring control. The vehicle control device 12 may determine whether or not it is possible to perform heat retention motoring control based on the load on the generator 4. That is, if the state of charge (SOC) of the drive battery 6 decreases and energy consumption due to heat rise motoring is suppressed, the vehicle control device 12 may determine that it is possible to perform heat retention motoring control. Also, if it determines that it is possible to reach a temperature sufficient to vaporize the fuel in the internal combustion engine 1 (for example, 20 degrees Celsius or higher) by performing heat retention motoring control, the vehicle control device 12 may determine that it is possible to perform heat retention motoring control. If the vehicle control device 12 determines that it is possible to perform heat retention motoring (step S11 YES), it proceeds to step S12.
[0043] In step S12, the vehicle control device 12 performs heat retention motoring control. Specifically, it turns off the heating device 38 and stops the motoring cam from shutting down. After performing heat retention motoring control, the vehicle control device 12 proceeds to step S7.
[0044] If the vehicle control device 12 determines in step S11 that it is not possible to perform the heat retention motoring control (step S11 NO), the vehicle control device 12 proceeds to step S7 and skips the heat rise motoring control.
[0045] If the vehicle control device 12 determines in step S8 that it is not a cold start (step S8 NO), the vehicle control device 12 proceeds to step S13. In step S13, the vehicle control device 12 determines whether or not it is performing a fuel cut. If the vehicle control device 12 determines that it is performing a fuel cut (step S13 YES), it proceeds to step S14.
[0046] In step S14, the vehicle control device 12 obtains the motoring time. The motoring time may be calculated by the vehicle control device 12 in the same way as in step S3. Once the vehicle control device 12 obtains the motoring time, it proceeds to step S15.
[0047] In step S15, the vehicle control device 12 performs heat retention motoring control, similar to step S4. After performing heat retention motoring control, the vehicle control device 12 proceeds to step S7.
[0048] In this manner, the vehicle control device 12 switches between warming motoring control and warming motoring control depending on the operating state of the internal combustion engine 1, such as cold start, extremely cold start, and fuel cut-off. The vehicle control device 12 prioritizes warming motoring control in the extremely cold state. In the extremely cold state, the friction of the internal combustion engine 1 during motoring is large due to the viscosity of the oil in the internal combustion engine 1. In warming motoring control, the movement of gas from the first cylinder 50a to the second cylinder 50b can assist in the downward pushing action of the piston 48 of the second cylinder 50b. For this reason, warming motoring control can suppress pump loss compared to warming motoring control. In addition, power consumption can be reduced because the heating device 38 is not turned on. In warming motoring control, the gas that has received frictional heat from the sliding of the piston 48 of the first cylinder 50a flows into the second cylinder 50b, and that gas receives frictional heat from the sliding of the piston 48 of the second cylinder 50b. Furthermore, the air is compressed within each cylinder 50, causing the temperature of each cylinder 50 to rise. This repeated process warms up the internal combustion engine 1. This improves fuel atomization when the internal combustion engine 1 is ignited and fuel is injected. As a result, emissions during the startup of the internal combustion engine 1 are improved.
[0049] Furthermore, the vehicle control device 12 prioritizes warm-up motoring control during cold starts. During cold starts, the friction of the internal combustion engine 1 is lower than during extremely cold starts. Therefore, the load on the generator 4 is also lower than during extremely cold starts. In addition, the power that the drive battery 6 can output is also greater than during extremely cold starts. In such cases, the vehicle control device 12 quickly warms up the internal combustion engine 1 by prioritizing warm-up motoring control. This allows the engine to reach a temperature state where fuel atomization is optimal more quickly. Also, with warm-up motoring control, the heating device 38 is turned on, which shortens the time it takes for the catalyst 40 to reach its activation temperature.
[0050] Furthermore, the vehicle control device 12 performs thermal motoring control when fuel is cut off. When fuel is cut off, the internal combustion engine 1 is rotating, so the rotational speed is higher than when starting. Therefore, if motoring is performed in this state, the load on the generator 4 is also high. For this reason, it is preferable to reduce the load on the generator 4 by performing thermal motoring control. Moreover, with thermal motoring control, the exhaust remains in the exhaust passage 46, which suppresses the temperature drop of the catalyst 40. As a result, the decrease in the purification performance of the catalyst 40 when fuel is restored after cut off can be suppressed.
[0051] As explained above, this disclosure provides a control system for an internal combustion engine that can realize novel motoring.
[0052] <Other Embodiments> Although embodiments of the present disclosure have been described above, the present disclosure is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention. In particular, the various modifications described herein can be combined as needed.
[0053] (a) In the above embodiments, an example in which the internal combustion engine 1 has four cylinders 50 has been described, but the disclosure is not limited thereto. The internal combustion engine 1 may have at least two or more cylinders 50.
[0054] (b) In the embodiments described above, an example was described in which temperature-keeping motoring control and temperature-raising motoring control were performed by switching between a firing cam and a motoring cam, but the disclosure is not limited thereto. The intake valve 35 and the exhaust valve 37 may be operated in any way that enables temperature-keeping motoring control and temperature-raising motoring control to be performed.
[0055] (c) In the above embodiment, examples of prioritizing either the heat retention motoring control or the heat rise motoring control according to the load on the generator 4 were given using the extremely cold start, cold start, and fuel cut-off as examples, but the disclosure is not limited thereto. Any other operating state of the internal combustion engine 1 is acceptable as long as either the heat retention motoring control or the heat rise motoring control is prioritized according to the load on the generator 4.
[0056] (d) In the above embodiment, an example in which a heating device 38 is provided in the exhaust passage 46 was used for explanation, but the disclosure is not limited thereto. For example, as shown in Figure 8, a heating device 38 may be provided in the intake passage 49. In this case, a heating device 38 may be provided in each port from the first cylinder 50a to the fourth cylinder 50d. Furthermore, in this case, the intake motoring cam may be the same cam as the exhaust motoring cam. The vehicle control device 12 may perform the heat retention motoring control by the intake motoring cam when the throttle 42 is closed. [Explanation of symbols]
[0057] 1: Internal combustion engine, 4: Generator (an example of a rotating electric machine) 38: Heating device, 40: Catalyst 50: Cylinder, 50a: 1st cylinder, 50b: 2nd cylinder
Claims
1. An internal combustion engine having a first cylinder and a second cylinder different from the first cylinder, A rotating electric machine capable of driving the aforementioned internal combustion engine, A control device that controls the internal combustion engine and the rotating electric machine, A heating device for heating the aforementioned gas, Equipped with, The control device is capable of performing a first motoring control, which drives the internal combustion engine with the rotating electric machine to move the gas in the first cylinder from the first cylinder to the second cylinder, and a second motoring control, which drives the internal combustion engine with the rotating electric machine to move the gas heated by the heating device to the first cylinder. The control device prioritizes executing the first motoring control when the load on the rotating electric machine is above a predetermined level, and prioritizes executing the second motoring control when the load on the rotating electric machine is below a predetermined level. Control system for internal combustion engines.
2. The control system for an internal combustion engine according to claim 1, wherein the control device performs the first motoring control when it performs fuel cut-off for the internal combustion engine.
3. The control system for an internal combustion engine according to claim 1, wherein the control device prioritizes executing the first motoring control when performing an extremely cold start of the internal combustion engine.
4. The control system for an internal combustion engine according to claim 1, wherein the control device prioritizes executing the second motoring control when performing a cold start of the internal combustion engine.