Control device for internal combustion engine

Abstract

Provided is a control device for an internal combustion engine capable of suppressing abnormal combustion caused by an overlong fuel injection period. A control device for an internal combustion engine calculates a torque upper limit value such that the torque upper limit value becomes smaller as the fuel pressure in a fuel tank detected by a tank pressure sensor becomes lower. A control device for an internal combustion engine compares a requested torque with a torque upper limit value, and when the requested torque is equal to or less than the torque upper limit value (step S140: YES), sets a fuel injection period so as to inject a fuel in an amount necessary to generate a torque corresponding to the requested torque. On the other hand, when the required torque is greater than the torque upper limit value (step S140: No), the control device of the internal combustion engine sets the fuel injection period so as to inject fuel in an amount necessary to generate torque corresponding to the torque upper limit value. A control device for an internal combustion engine controls an injector in accordance with the set fuel injection period (step S120).

Description

Technical Field

[0001] This invention relates to a control device for an internal combustion engine. Background Technology

[0002] Patent Document 1 discloses a control device for an internal combustion engine that burns hydrogen-containing fuel. This control device detects the temperature and pressure of the fuel supplied from the fuel tank to the injector, and adjusts the opening time of the injector that injects fuel into one cylinder in one cycle based on this temperature and pressure. That is, it adjusts the fuel injection period based on the injector. When the fuel tank pressure is low, this control device ensures the injection quantity by extending the injection period, thereby enabling the injection of the desired amount of fuel from the injector.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2023-057489 Summary of the Invention

[0004] If the injection period is too long, an ideal mixture of hydrogen and air cannot be formed in the combustion chamber, which may cause abnormal combustion.

[0005] The following describes the solutions used to address the above problems and their effects.

[0006] The control device for an internal combustion engine designed to solve the aforementioned problems includes a processing circuit. The processing circuit calculates an upper limit torque value such that the lower the fuel pressure in the fuel tank detected by a tank pressure sensor, which detects the fuel pressure in the fuel tank, the smaller the upper limit torque value. The processing circuit compares the required torque with the upper limit torque value. If the required torque is below the upper limit torque value, the processing circuit sets the fuel injection period of the internal combustion engine's injector in a manner that injects the amount of fuel required to generate a torque equivalent to the required torque. Conversely, if the required torque is greater than the upper limit torque value, the processing circuit sets the fuel injection period of the internal combustion engine's injector in a manner that injects the amount of fuel required to generate a torque equivalent to the upper limit torque value. The internal combustion engine's injector is controlled according to the fuel injection period set by the processing circuit.

[0007] Invention Effects

[0008] The aforementioned control device for internal combustion engines can prevent excessively long fuel injection periods, thus suppressing abnormal combustion. Attached Figure Description

[0009] Figure 1 This is a schematic diagram illustrating the fuel injection system of a vehicle equipped with a control device for an internal combustion engine according to the embodiments. Figure 2 This is a schematic diagram illustrating the process of determining the fuel injection period of the internal combustion engine injector in a vehicle's fuel injection system. Figure 3 This is a schematic diagram illustrating the process of determining the upper limit of torque using a control device for an internal combustion engine according to the same implementation method. Figure 4 This is a flowchart illustrating a series of processes related to the control of the injector in a control device for an internal combustion engine based on the same implementation. Detailed Implementation

[0010] The following is for reference. Figures 1-4 The control device 40 of the internal combustion engine 30 according to the embodiment will be described.

[0011] <Vehicle fuel injection system>

[0012] The control device 40 of the internal combustion engine 30 according to the embodiment is mounted on a vehicle and constitutes the vehicle's fuel injection system. The control device 40 includes a processing circuit 41. The processing circuit 41 performs various processes for controlling the internal combustion engine 30. For example... Figure 1 As shown, the vehicle's fuel injection system includes, from the fuel tank 10 side, a tank shut-off valve 11, a pressure reducing valve 14, a safety valve 20, a delivery shut-off valve 21, and an internal combustion engine 30. The internal combustion engine 30 includes a delivery pipe 31, an injector 34, and an output shaft 35.

[0013] Fuel tank 10 is a container for storing hydrogen used during vehicle operation under high pressure. Tank shut-off valve 11 is a valve that controls the flow of hydrogen from fuel tank 10. When driving begins, tank shut-off valve 11 opens, and hydrogen is delivered from fuel tank 10.

[0014] The hydrogen supplied from fuel tank 10 is at a very high pressure, and pressure reducing valve 14 is used to reduce this high pressure to an appropriate level. Pressure reducing valve 14 adjusts the pressure of the hydrogen from fuel tank 10 to a pressure suitable for fuel injection from injector 34. A tank pressure sensor 12, which monitors the pressure of the hydrogen within fuel tank 10, is installed in the section of the fuel supply line between tank shut-off valve 11 and pressure reducing valve 14. A tank temperature sensor 13, which monitors the temperature of the hydrogen within fuel tank 10, is also installed in the section of the fuel supply line between tank shut-off valve 11 and pressure reducing valve 14.

[0015] Safety valve 20 is closed during normal driving, but opens to release excessive pressure in the event of abnormally high pressure in the fuel injection line. This ensures that the pressure within the fuel injection system remains within a safe range.

[0016] The supply shut-off valve 21 cuts off the hydrogen supply when the engine is stopped. Conversely, the supply shut-off valve 21 opens when the engine is started, supplying hydrogen to the supply pipe 31. The supply shut-off valve 21 also cuts off the hydrogen supply in an emergency. The supply pipe 31 is a passage for supplying hydrogen to the injector 34. A supply pressure sensor 32 for monitoring the pressure of the hydrogen within the supply pipe 31 and a supply temperature sensor 33 for monitoring the temperature of the hydrogen within the supply pipe 31 are installed on the supply pipe 31.

[0017] The injector 34 opens and closes according to the operating state of the internal combustion engine 30, supplying hydrogen to the combustion chamber. The internal combustion engine 30 generates power by mixing hydrogen and air and burning them. When hydrogen is supplied from the injector 34, the combustion process in the internal combustion engine 30 begins. The energy generated by this combustion becomes the rotational force of the output shaft 35, which in turn becomes the driving force of the vehicle. The internal combustion engine speed sensor 36 measures the internal combustion engine speed. The internal combustion engine speed is the rotational speed of the output shaft 35. The internal combustion engine speed is used for output control of the internal combustion engine 30 or adjustment of the fuel supply.

[0018] The control unit 40 of the internal combustion engine 30 processes information from various sensors from the fuel tank 10 to the injector 34, and controls the optimization of hydrogen supply, the adjustment of the operation of the internal combustion engine 30, and the operation of safety functions. Thus, the process of supplying hydrogen from the fuel tank 10 to the combustion chamber via the injector 34 and utilizing it as power for the vehicle ends.

[0019] <The process of determining the fuel injection period of the injector 34 of the internal combustion engine 30>

[0020] Figure 2 The processing circuit 41 of the control device 40 determines the process during fuel injection by the injector 34 of the internal combustion engine 30. For example... Figure 2 As shown, the processing circuit 41 uses throttle opening, vehicle speed, and gear shift to calculate the required torque output of the internal combustion engine 30. This calculation determines the "required torque." Required torque refers to the torque that the internal combustion engine 30 should produce based on the vehicle's current driving conditions, such as throttle opening, vehicle speed, and gear shift.

[0021] Next, processing circuit 41 calculates the amount of fuel to be injected from injector 34, i.e., the required injection quantity, based on the required torque calculated above. The required injection quantity is the amount of fuel injected in one cylinder cycle required to achieve the required torque. If the required injection quantity is calculated, processing circuit 41 uses the calculated required injection quantity, fuel pressure in delivery pipe 31, fuel temperature, and internal combustion engine speed to determine the fuel injection period corresponding to the required injection quantity. The fuel injection period is determined based on the valve opening and closing periods of injector 34. By determining the valve opening and closing periods of injector 34, processing circuit 41 determines the period of fuel injection and the duration of continuous fuel injection, i.e., the fuel injection period.

[0022] Thus, the processing circuit 41 uses information from multiple sensors, such as the delivery pressure sensor 32, the delivery temperature sensor 33, and the internal combustion engine speed sensor 36, to control the operation of the injector 34. Furthermore, the processing circuit 41 also uses information from the tank pressure sensor 12 and the tank temperature sensor 13 to precisely control the operation of the injector 34. The control of the injector 34 using information from the tank pressure sensor 12 will be described later.

[0023] The control device 40 of the internal combustion engine 30 achieves optimal fuel supply corresponding to the driving conditions of the vehicle.

[0024] As described above, starting with the calculation of the required torque, the injection timing of the injector 34 and the fuel injection period are ultimately determined. By actuating the injector 34 to achieve the determined injection timing and fuel injection period, the internal combustion engine 30 produces a torque equivalent to the required torque.

[0025] Furthermore, the control device 40 of the internal combustion engine 30 sets a torque upper limit value and generates torque within a range not exceeding the torque upper limit value.

[0026] <The process by which the control device 40 of the internal combustion engine 30 determines the upper limit value of torque>

[0027] Figure 3 This describes the process by which the control device 40 of the internal combustion engine 30 determines the upper limit value of the torque. This process is executed by the processing circuit 41 of the control device 40.

[0028] like Figure 3 As shown, firstly, the processing circuit 41 calculates the upper limit of flow rate using the fuel pressure in the fuel tank 10 detected by the tank pressure sensor 12 and the fuel pressure in the delivery pipe 31 detected by the delivery pressure sensor 32. The control device 40 stores a flow rate upper limit calculation mapping designed to output the upper limit of flow rate by inputting the pressure in the fuel tank 10 and the pressure in the delivery pipe 31. The upper limit of flow rate is the maximum fuel flow rate that can be supplied to the injector 34, estimated based on the fuel pressure in the fuel tank 10 and the fuel pressure in the delivery pipe 31. The flow rate upper limit calculation mapping is a stored operational mapping of the upper limit of flow rate corresponding to the combination of the fuel pressure in the fuel tank 10 and the fuel pressure in the delivery pipe 31. The flow rate upper limit calculation mapping is designed based on the results of experiments or simulations conducted during the design phase, such that the lower the fuel pressure in the fuel tank 10, the smaller the output upper limit of flow rate, and the lower the fuel pressure in the delivery pipe 31, the smaller the output upper limit of flow rate.

[0029] Next, the processing circuit 41 uses the calculated upper limit of flow rate and the internal combustion engine speed to calculate the upper limit of injection quantity. The control device 40 stores an upper limit of injection quantity calculation map designed to output the upper limit of injection quantity by inputting the upper limit of flow rate and the internal combustion engine speed. The upper limit of injection quantity is the maximum amount of fuel that can be injected from the injector 34, estimated based on the upper limit of flow rate and the internal combustion engine speed. The upper limit of injection quantity calculation map is designed based on the results of experiments or simulations conducted during the design phase, such that the smaller the upper limit of flow rate, the smaller the upper limit of injection quantity, and the higher the internal combustion engine speed, the smaller the upper limit of injection quantity.

[0030] Furthermore, the processing circuit 41 uses the calculated upper limit of the injection quantity and the internal combustion engine speed to calculate the upper limit of the torque. The control device 40 stores a torque upper limit calculation map designed to output the upper limit of torque by inputting the upper limit of the injection quantity and the internal combustion engine speed. The upper limit of torque is the maximum torque that the engine can produce, estimated based on the upper limit of the injection quantity and the internal combustion engine speed. The torque upper limit calculation map is designed based on the results of experiments or simulations conducted during the design phase, so that the smaller the upper limit of the injection quantity, the smaller the upper limit of torque, and the higher the internal combustion engine speed, the smaller the upper limit of torque.

[0031] <Control of injector 34 based on control device 40>

[0032] The following is for reference. Figure 4 The control of the injector 34 based on the control device 40 will be described. Whenever in reference... Figure 2 When the required torque is calculated during the explanation process, the processing circuit 41 executes... Figure 4 The series of processes shown.

[0033] First, in step S100, the processing circuit 41 determines whether the fuel pressure in the fuel tank 10 is above a predetermined value. The predetermined value is, for example, the lower limit of the pressure range that can be adjusted by the pressure reducing valve 14. In this case, the predetermined value is set to determine that the remaining amount of fuel in the fuel tank 10 is too low to maintain the pressure downstream of the pressure reducing valve 14. The magnitude of the predetermined value is set such that if the fuel pressure in the fuel tank 10 is lower than the predetermined value, it can be determined that the pressure downstream of the pressure reducing valve 14 cannot be maintained.

[0034] In step S100, if the processing circuit 41 determines that the fuel pressure in the fuel tank 10 is above a predetermined value (step S100: "Yes"), the processing proceeds to step S110. In step S110, the processing circuit 41 proceeds according to the reference... Figure 2The process described involves calculating the fuel injection period of the injector 34 of the internal combustion engine 30 in such a way that the amount of fuel required to generate a torque equivalent to the desired torque is injected. Furthermore, in step S120, the processing circuit 41 controls the injector 34 in a manner that implements the fuel injection period calculated in step S110. When the injector 34 is controlled in this way, the processing circuit 41 temporarily terminates this series of processes.

[0035] On the other hand, in step S100, if the processing circuit 41 determines that the fuel pressure in the fuel tank 10 is less than a predetermined value (step S100: "No"), the processing proceeds to step S130. In step S130, the processing circuit 41 follows the reference... Figure 3 The process described uses the fuel pressure in the fuel tank 10 and the fuel pressure in the delivery pipe 31 to calculate the upper limit of torque. Furthermore, the processing circuit 41 initiates step S140, comparing the required torque with the upper limit of torque calculated in step S130.

[0036] In step S140, if the processing circuit 41 determines that the required torque is below the upper limit of the torque value (step S140: "Yes"), the processing proceeds to step S110, according to the reference... Figure 2 The process described involves calculating the fuel injection period of the injector 34 of the internal combustion engine 30 in such a way that the amount of fuel required to generate a torque equivalent to the desired torque is injected. Furthermore, in step S120, the processing circuit 41 controls the injector 34 in a manner that implements the fuel injection period calculated in step S110. When the injector 34 is controlled in this way, the processing circuit 41 temporarily terminates this series of processes.

[0037] On the other hand, in step S140, if it is determined that the required torque is greater than the upper limit of torque (step S140: "No"), the processing circuit 41 proceeds to step S150. In step S150, the processing circuit 41 calculates the amount of fuel required to generate torque equivalent to the upper limit of torque during the fuel injection period of the injector 34 of the internal combustion engine 30. At this time, the processing circuit 41 refers to... Figure 2 During the process, the torque will be changed to the upper limit value to calculate the fuel injection period of the injector 34. Furthermore, the processing circuit 41 initiates step S120 to control the injector 34 in accordance with the fuel injection period calculated in step S150. While controlling the injector 34 in this way, the processing circuit 41 temporarily terminates this series of processes.

[0038] <The function of this implementation method>

[0039] The control device 40 of the internal combustion engine 30 includes a processing circuit 41. The processing circuit 41 calculates a torque upper limit value such that the lower the fuel pressure in the fuel tank 10 detected by the tank pressure sensor 12 (which detects fuel pressure within the fuel tank 10), the smaller the torque upper limit value. The processing circuit 41 compares the required torque with the torque upper limit value. If the required torque is below the torque upper limit value (step S140: "Yes"), it sets the fuel injection period of the injector 34 of the internal combustion engine 30 to the amount of fuel required to generate a torque equivalent to the required torque (step S110). On the other hand, if the required torque is greater than the torque upper limit value (step S140: "No"), the processing circuit 41 sets the fuel injection period of the injector 34 of the internal combustion engine 30 to the amount of fuel required to generate a torque equivalent to the torque upper limit value (step S150). The processing circuit 41 controls the injector 34 according to the fuel injection period set by the processing in step S110 or step S150 (step S120).

[0040] The fuel injection period set according to the upper limit of torque is shorter than the fuel injection period set according to the required torque. Therefore, in situations where abnormal combustion would occur if the fuel injection period was set according to the required torque due to low fuel pressure in the fuel tank 10, a fuel injection period shorter than the fuel injection period set according to the required torque is set.

[0041] <Effects of this implementation method>

[0042] (1) The control device 40 of the internal combustion engine 30 can prevent the fuel injection period from being too long, thus suppressing abnormal combustion.

[0043] (2) In the control device 40 of the internal combustion engine 30, the processing circuit 41 uses the fuel pressure in the fuel tank 10 detected by the tank pressure sensor 12, and also uses the internal combustion engine speed to calculate the upper limit of torque in such a way that the higher the internal combustion engine speed, the smaller the upper limit of torque.

[0044] The higher the internal combustion engine speed, the shorter the fuel injection period suitable for forming an ideal air-fuel mixture. In addition to using the fuel pressure in the fuel tank 10 detected by the tank pressure sensor 12, the control device 40 of the internal combustion engine 30 also uses the internal combustion engine speed to calculate the upper limit of torque. Thus, because the internal combustion engine speed is taken into account when calculating the upper limit of torque, the control device 40 of the internal combustion engine 30 can accurately calculate the upper limit of torque even if the internal combustion engine speed changes.

[0045] Therefore, the control device 40 of the internal combustion engine 30 can limit the required torque to an upper limit value corresponding to the driving conditions of the vehicle, and thus can more appropriately control the fuel injection period of the injector 34.

[0046] (3) In the control device 40 of the internal combustion engine 30, the processing circuit 41 uses the fuel pressure in the fuel tank 10 detected by the tank pressure sensor 12, and also uses the fuel pressure in the delivery pipe 31 detected by the delivery pressure sensor 32 that detects the fuel pressure in the delivery pipe 31 that supplies fuel from the fuel tank 10 to the injector 34, to calculate the upper limit of torque, so that the lower the fuel pressure in the delivery pipe 31, the smaller the upper limit of torque.

[0047] The amount of fuel injected from the injector 34 changes due to variations in fuel pressure within the delivery pipe 31. Since the fuel pressure within the delivery pipe 31 is taken into account when calculating the upper limit of torque, the control device 40 of the internal combustion engine 30 can accurately calculate the upper limit of torque even when the fuel pressure within the delivery pipe 31 changes.

[0048] Therefore, the control device 40 of the internal combustion engine 30 can calculate an appropriate upper limit of torque that reflects the fuel pressure in the fuel tank 10 and the fuel pressure in the delivery pipe 31, and control the fuel injection period of the injector 34.

[0049] (4) In the control device 40 of the internal combustion engine 30, the processing circuit 41 uses the fuel pressure in the fuel tank 10 detected by the tank pressure sensor 12 and the fuel pressure in the delivery pipe 31 detected by the delivery pressure sensor 32, which detects the fuel pressure in the delivery pipe 31 that supplies fuel from the fuel tank 10 to the injector 34, to calculate the maximum flow rate of fuel flowing to the injector 34 in one cycle, i.e., the upper limit of flow rate. The processing circuit 41 uses the calculated upper limit of flow rate and the internal combustion engine speed to calculate the maximum amount of fuel that can be injected from the injector 34 in one cycle, i.e., the upper limit of injection quantity. The processing circuit 41 uses the calculated upper limit of injection quantity and the internal combustion engine speed to calculate the upper limit of torque.

[0050] If the fuel pressure in the fuel tank 10 and the fuel pressure in the delivery pipe 31 decreases, the maximum flow rate of fuel that can be supplied to the injector 34, i.e., the upper limit of the flow rate, decreases. If the upper limit of the flow rate is small, then the maximum amount of fuel that can be injected from the injector 34 in one cycle, i.e., the upper limit of the injection amount, also decreases.

[0051] The control device 40 of the internal combustion engine 30 uses the fuel pressure in the fuel tank 10, the fuel pressure in the delivery pipe 31, and the internal combustion engine speed to calculate the upper limit value of the flow rate and the upper limit value of the injection quantity. Thus, based on an estimate of the upper limit value of the injection quantity corresponding to the fuel pressure in the fuel tank 10, the control device 40 of the internal combustion engine 30 uses the internal combustion engine speed to calculate the upper limit value of the torque.

[0052] Therefore, the control device 40 of the internal combustion engine 30 can calculate the upper limit of torque taking into account the fuel pressure in the fuel tank 10 and the current driving state of the internal combustion engine 30.

[0053] (5) In the control device 40 of the internal combustion engine 30, the processing circuit 41 does not calculate the upper limit of torque when the fuel pressure in the fuel tank 10 is above a predetermined value, and sets the fuel injection period of the injector 34 in such a way as to inject the amount of fuel required to generate a torque equivalent to the required torque.

[0054] If the fuel pressure in the fuel tank 10 is sufficiently high, the required amount of fuel can be injected even if the fuel injection period of the injector 34 is short. Therefore, if the fuel pressure in the fuel tank 10 is sufficiently high, the control device 40 of the internal combustion engine 30 does not need to limit the required torque by a torque upper limit value. When the fuel pressure in the fuel tank 10 is above a predetermined value, the control device 40 of the internal combustion engine 30 does not calculate the torque upper limit value and sets the fuel injection period according to the required torque.

[0055] Therefore, the control device 40 of the internal combustion engine 30 can suppress the excessive limitation of the required torque by the upper limit of torque.

[0056] <Example of Change>

[0057] This embodiment can be modified as follows. This embodiment and the following modifications can be combined with each other within the scope of technical inconsistency.

[0058] In one embodiment, a delivery pipe 31 is provided on the fuel injection line of the vehicle's fuel injection system, but it is not always necessary, and the pressure reducing valve 14 and the delivery pipe 31 may not be provided. In this case, the control device 40 of the internal combustion engine 30 calculates the upper limit of torque using only the fuel pressure in the fuel tank 10 detected by the tank pressure sensor 12, so that the lower the fuel pressure in the fuel tank 10, the smaller the upper limit of torque. In this case, the processing circuit 41 uses the required injection quantity, the fuel pressure in the fuel tank 10, the fuel temperature, and the internal combustion engine speed to determine the fuel injection period corresponding to the required injection quantity.

[0059] In the control device 40 of the internal combustion engine 30 according to the embodiment, the upper limit of torque is calculated using the internal combustion engine speed, so that the higher the internal combustion engine speed, the smaller the upper limit of torque. However, the control device 40 of the internal combustion engine 30 described above may calculate the upper limit of torque without using the internal combustion engine speed, but using the fuel pressure in the fuel tank 10 detected by the tank pressure sensor 12 and the fuel pressure in the delivery pipe 31 detected by the delivery pressure sensor 32.

[0060] Symbol Explanation

[0061] 10-Fuel tank, 11-Tank shut-off valve, 12-Tank pressure sensor, 13-Tank temperature sensor, 14-Pressure reducing valve, 20-Safety valve, 21-Delivery shut-off valve, 30-Internal combustion engine, 31-Delivery pipe, 32-Delivery pressure sensor, 33-Delivery temperature sensor, 34-Injector, 35-Output shaft, 36-Internal combustion engine speed sensor, 40-Control device, 41-Processing circuit.

Claims

1. A control device for an internal combustion engine, mounted in a vehicle, for controlling an internal combustion engine that supplies fuel using fuel pressure, characterized in that... Equipped with processing circuitry, The processing circuit calculates the upper limit of torque in such a way that the lower the fuel pressure in the fuel tank, as detected by a tank pressure sensor, the lower the torque. The processing circuit compares the required torque with the upper limit of torque. If the required torque is below the upper limit of torque, it sets the fuel injection period of the internal combustion engine's injector in such a way that it injects the amount of fuel required to generate torque equivalent to the required torque. If the required torque is greater than the upper limit of torque, it sets the fuel injection period of the internal combustion engine's injector in such a way that it injects the amount of fuel required to generate torque equivalent to the upper limit of torque. The injectors of the internal combustion engine are controlled according to the fuel injection period set by the processing circuit.

2. The control device for an internal combustion engine according to claim 1, characterized in that, The processing circuit performs the following processing: In addition to the fuel pressure inside the fuel tank detected by the tank pressure sensor, the upper limit of torque is calculated using the internal combustion engine speed, such that the higher the internal combustion engine speed, the smaller the upper limit of torque.

3. The control device for an internal combustion engine according to claim 2, characterized in that, The processing circuit performs the following processing: In addition to the fuel pressure in the fuel tank detected by the tank pressure sensor, the upper limit of torque is calculated using the fuel pressure in the delivery pipe detected by the delivery pressure sensor that detects the fuel pressure in the delivery pipe that supplies fuel from the fuel tank to the injector, in such a way that the lower the fuel pressure in the delivery pipe, the smaller the upper limit of torque.

4. The control device for an internal combustion engine according to claim 3, characterized in that, The processing circuit performs the following processing: Using the fuel pressure in the fuel tank detected by the tank pressure sensor and the fuel pressure in the delivery pipe detected by the delivery pressure sensor that detects the fuel pressure in the delivery pipe that supplies fuel from the fuel tank to the injector, the maximum flow rate of fuel flowing to the injector in one cycle is calculated, i.e., the upper limit of the flow rate. Using the calculated upper limit of the flow rate and the internal combustion engine speed, calculate the maximum amount of fuel that can be injected from the injector in one cycle, i.e., the upper limit of the injection quantity. and The upper limit of the injection quantity and the internal combustion engine speed are used to calculate the upper limit of the torque.

5. The control device for an internal combustion engine according to claim 1, characterized in that, The processing circuit performs the following processing: When the fuel pressure in the fuel tank is above a predetermined value, the upper limit of torque is not calculated, but the fuel injection period of the injector is set in such a way that the amount of fuel required to generate a torque equivalent to the required torque is injected.

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