JP4155168B2 - Common rail fuel injection system - Google Patents

Description

  The present invention relates to a common rail fuel injection device, and more particularly to control of an intake metering valve (hereinafter referred to as SCV) that adjusts the pressure of a common rail by adjusting the flow rate of fuel sucked into a supply pump.

The common rail type fuel injection device is configured to supply high pressure fuel from a supply pump to the common rail and inject high pressure fuel accumulated in the common rail from the injector. The common rail pressure is adjusted by a suction metering valve mounted on the supply pump, and the common rail pressure is controlled by varying a drive current value of a solenoid mounted on the suction metering valve (for example, a patent) Reference 1).
JP 2000-282929 A

(1) First Problem When starting an internal combustion engine (hereinafter referred to as an engine), an ECU (abbreviation of engine control unit) is configured to output a pump discharge amount (from a program given in advance) according to the engine start. (Calculated value) is calculated, the drive current value corresponding to the pump discharge amount is given to the SCV, and the actual rail pressure (common rail actual pressure) is set to the target rail pressure (common rail target pressure according to engine start). The engine is starting up.
However, when starting the engine with a low outside air temperature, such as in the cold season, the fuel viscosity increases due to the low temperature, and the actual rail pressure starts even if the SCV opening reaches the target opening. There is a possibility that the target rail pressure corresponding to the time is not reached and the startability is lowered.

(2) Second Problem FIG. 6 shows the relationship between the drive current value (I) given from the ECU to the SCV and the discharge amount (Q) of the supply pump. In FIG. 6, as indicated by a broken line, the discharge amount (Q) of the supply pump varies with the difference in the supply pump, etc. with respect to the drive current value (drive current I in the figure).

The common rail fuel injection device corrects the drive current value (or the basic pump discharge amount before calculating the drive current value) based on the differential pressure between the target rail pressure and the actual rail pressure, and suppresses the above-described machine difference variation. Feedback control (hereinafter, feedback is referred to as F / B) is provided.
In this F / B control, a proportional term and an integral term are obtained based on the differential pressure between the target rail pressure and the actual rail pressure, and a drive current value (or a drive current value before the drive current value is calculated based on the proportional term and the integral term). Basic pump discharge amount) is corrected.

  On the other hand, in the common rail fuel injection device, learning correction of the supply pump is performed. This learning correction is performed when the learning condition (for example, when the engine is in a stable state such as idling and the value of the integral term continues for a certain time or longer) is satisfied when the engine is in a stable state such as idling. The integral term in the B control is stored as a learning value, and the driving current value (or basic pump discharge amount before calculating the driving current value) is corrected using the stored learning value.

  Here, referring to FIG. 7, the actual rail pressure (rail pressure in the figure) and the opening degree of SCV (in the figure) when foreign matter is caught in SCV in the engine stable state (idling state). , SCV opening), drive current value (pump drive current I in the figure), proportional term (F / B proportional term Ip in the figure), integral term (F / B integral term Ii in the figure), learning value ( In the figure, the time series change of the learning value Iq) will be described.

  When a foreign object is caught in the SCV (see a1 in the figure) and the opening of the SCV increases (see a2 in the figure), oversupply of the supply pump occurs and the actual rail pressure rises (in the figure, a3). As a result, in order to make the actual rail pressure coincide with the target rail pressure, the proportional term (Ip) and the integral term (Ii) change (see a4 in the figure), and the drive current value (I) is corrected (in the figure). A5). As a result, the actual rail pressure is corrected to the target rail pressure.

In this way, when the foreign matter is caught in the SCV and the supply pump is over-pressured, the integral term (Ii) becomes a negative value (a value that reduces the discharge amount), and the learning condition is satisfied in that state ( The integral term (Ii) is converted into a learning value (Iq) (see a7 in the drawing), and the integral term (Ii) is reset.
When restarting while foreign matter is caught in the SCV (see the right side of the broken line in the figure), the learning value (Iq) before restarting is reflected in the drive current value (I) (a8 in the figure). reference). For this reason, the actual rail pressure rises to the target rail pressure due to cranking in which the engine is rotationally driven by the starter. As a result, the engine can be started well when the engine is restarted.

A time-series change of each value when the foreign matter caught in the SCV is removed will be described with reference to FIG.
When the foreign matter caught in the SCV is removed (see b1 in the figure), the SCV opening is returned to normal (see b2 in the figure). However, since the learned value (Iq) before the foreign matter is removed is reflected in the drive current value (I), the supply pump is insufficiently pumped and the actual rail pressure starts to decrease (see b3 in the figure). . Then, in order to make the actual rail pressure coincide with the target rail pressure, the proportional term (Ip) and the integral term (Ii) change (see b4 in the figure), and the drive current value (I) is corrected (b5 in the figure). reference). As a result, the actual rail pressure is corrected to the target rail pressure.
As described above, when the foreign matter caught in the SCV is removed and the supply pump is insufficiently pumped, the integral term (Ii) becomes a positive value (a value for increasing the discharge amount), and the learning condition is satisfied in that state ( The integral term (Ii) is converted into a learning value (Iq) (see the broken line b7 in the figure), and the integral term (Ii) is returned to the state before the foreign object bites. As a result, the engine can be started well after the engine is stopped.

However, it is conceivable that the engine is stopped before the learning condition is satisfied after the foreign matter caught in the SCV is removed.
In such a case, the learning value (Iq) before the restart is reflected in the drive current value (I) and the opening degree of the SCV is suppressed even though the foreign matter caught in the SCV is removed. (Refer to b8 in the figure) Even if the cranking is carried out for a long time, the increase in the actual rail pressure is suppressed. As a result, the cranking time at the time of restart becomes longer and the startability is poor.

[Object of invention]
The present invention has been made in view of the above problems, and its purpose is to (1) When the engine starts, (1) When the viscosity of the fuel increases at low temperatures and the discharge capacity of the supply pump decreases, 2) Even when the foreign matter caught in the SCV has been removed, even if the supply value of the supply pump is reduced without returning the learning value in the state where the foreign matter is stuck, the start time Is to provide a common rail fuel injection device capable of shortening the fuel consumption.

[Means of Claims 1 and 2]
The common rail type fuel injection device adopting the means of claims 1 and 2 increases the gain of the integral term when the cranking time of the engine passes a predetermined time.
As a result, the opening of the SCV at the start of the engine is increased, the discharge capacity of the supply pump is increased, and the actual rail pressure is rapidly increased, so that the startability can be improved and the start time can be shortened. That is, for example, even in a state where the viscosity of the fuel increases at low temperatures and the discharge capacity of the supply pump decreases, the SCV opening at the start of the engine is widened by increasing the gain of the integral term. Since the discharge capacity of the pump is increased and the actual rail pressure is increased, the startability can be improved and the start time can be shortened.

[Means of claim 3]
A common rail fuel injection device employing the means of claim 3 stores an integral term as a learned value when a predetermined learning condition is satisfied, and corrects the drive current value or the pump discharge amount using the stored learned value. Provide learning means.
By adopting this configuration, the engine is maintained in a state in which the discharge capacity of the supply pump is suppressed without returning the learned value in the state in which the foreign matter is caught while the foreign matter caught in the SCV is removed. May be stopped.
When restarting the engine in such a state, the learning value before the restart is reflected in the drive current value and the opening degree of the SCV is suppressed even though the foreign matter caught in the SCV is removed. Even if the cranking is performed for a long time, the increase in the actual rail pressure is suppressed.
However, in combination with the means of claim 1, the discharge value of the supply pump is suppressed without returning the learning value in the state where the foreign matter is caught even though the foreign matter caught in the SCV is removed. Even when the engine is cranked for a predetermined period of time, the gain of the integral term is increased, so that the opening of the SCV at the start of the engine is widened and the discharge capacity of the supply pump is increased. Since the actual rail pressure increases to increase the startability, the start time can be shortened.

[Means of claim 4]
The common rail type fuel injection device adopting the means of claim 4 gradually increases the gain of the integral term when the engine cranking time elapses a predetermined time.

The common rail fuel injection device of the best mode 1 includes a control device including an injector, a common rail, a supply pump, an SCV, and a feedforward control means for calculating a drive current value to be applied to the solenoid in accordance with the operating state of the engine.
The control device obtains a proportional term and an integral term based on the differential pressure between the target rail pressure and the actual rail pressure according to the operating state of the engine, and feedback control that corrects the drive current value based on the proportional term and the integral term. And an integral gain correcting means for increasing the gain of the integral term when the engine cranking time has passed a predetermined time.

The common rail type fuel injection device of the best mode 2 includes an injector, a common rail, a supply pump, an SCV, and feedforward control means for calculating the pump discharge amount of the supply pump according to the operating state of the engine, and according to the pump discharge amount. And a controller for supplying the drive current to the solenoid.
The control device obtains a proportional term and an integral term based on the differential pressure between the target rail pressure and the actual rail pressure according to the operating state of the engine, and the pump discharge amount (drive current value) based on the proportional term and the integral term. Feedback control means for correcting the basic pump discharge amount before calculating), and integral gain correction means for increasing the gain of the integral term when the cranking time of the engine passes a predetermined time.

  The common rail fuel injection device of the best mode 3 stores an integral term as a learned value when a predetermined learning condition is satisfied, in addition to the best mode 1 or the best mode 2, and uses the stored learned value. Learning means for correcting the drive current value or the pump discharge amount (basic pump discharge amount before calculating the drive current value) is provided.

A first embodiment will be described with reference to FIGS.
First, the configuration of the common rail fuel injection device will be described with reference to FIGS.
The common rail type fuel injection device is a device that injects fuel into, for example, a diesel engine (hereinafter referred to as an engine) 1 and includes a common rail 2, an injector 3, a supply pump 4, an ECU 5 (corresponding to a control device), and the like.

The common rail 2 is a pressure accumulating container for accumulating high-pressure fuel supplied to the injector 3, and the high-pressure fuel is connected via a fuel pipe (high-pressure fuel flow path) 6 so that a common rail pressure corresponding to the fuel injection pressure is continuously accumulated. Is connected to a discharge port of a supply pump 4 that discharges water.
The leaked fuel from the injector 3 is returned to the fuel tank 8 via a leak pipe (fuel return path) 7.
A pressure limiter 11 is attached to a relief pipe (fuel return path) 9 from the common rail 2 to the fuel tank 8. The pressure limiter 11 is a pressure safety valve that opens when the fuel pressure in the common rail 2 exceeds the limit set pressure, and keeps the fuel pressure in the common rail 2 below the limit set pressure.

  The injector 3 is installed in each cylinder of the engine 1 and supplies fuel to each cylinder by injection. The injector 3 is connected to the downstream ends of a plurality of branch pipes branched from the common rail 2 and is accumulated in the common rail 2. A fuel injection nozzle that injects fuel into each cylinder and an electromagnetic valve that performs lift control of a needle accommodated in the fuel injection nozzle are mounted.

The supply pump 4 will be described with reference to FIG.
This supply pump 4 feeds fuel compressed to a high pressure to the common rail 2 and is composed of a feed pump 12 (disclosed in a state of 90 ° expansion in the figure), a regulator valve 13, an SCV 14, a high-pressure pump 15, and the like. Is done.

The feed pump 12 is a low-pressure supply pump that sucks fuel from the fuel tank 8 and sends the fuel to the high-pressure pump 15, and is constituted by a trochoid pump that is rotationally driven by a camshaft 16. When the feed pump 12 is driven, the fuel sucked from the fuel inlet 17 is supplied to the high-pressure pump 15 via the SCV 14.
The camshaft 16 is a pump drive shaft, and is rotated by a crankshaft 18 of the engine 1 as shown in FIG.

  The regulator valve 13 is disposed in a fuel flow path 19 that communicates the discharge side and the supply side of the feed pump 12 and opens when the discharge pressure of the feed pump 12 rises to a predetermined pressure. The predetermined pressure is not exceeded.

The SCV 14 is disposed in a fuel passage 21 that guides fuel from the feed pump 12 to the high-pressure pump 15, and adjusts the amount of fuel sucked into the pressurizing chamber 22 (plunger chamber) of the high-pressure pump 15 to adjust the common rail pressure. Change and adjust.
The SCV 14 includes a valve 23 that changes the opening degree of the fuel passage 21 that guides fuel from the feed pump 12 to the high-pressure pump 15, and a linear solenoid 24 that adjusts the valve opening degree of the valve 23 by a drive current supplied from the ECU 5. In the first embodiment, a normally closed type in which the valve opening is fully closed when the energization of the solenoid 24 is stopped will be described as an example.

The high-pressure pump 15 is a plunger pump that compresses the fuel supplied from the SCV 14 to a high pressure and supplies the compressed fuel to the common rail 2. A suction valve 26 for supplying fuel to the pressure chamber 22 and a discharge valve 27 for discharging the fuel compressed in the pressurizing chamber 22 toward the common rail 2 are provided.
The plunger 25 is pressed against a cam ring 29 mounted around the eccentric cam 28 of the camshaft 16 by a spring 30. When the camshaft 16 rotates, the plunger 25 reciprocates with the eccentric operation of the cam ring 29.
When the plunger 25 is lowered and the pressure in the pressurizing chamber 22 is lowered, the discharge valve 27 is closed and the intake valve 26 is opened to supply the fuel adjusted by the SCV 14 into the pressurizing chamber 22. . Conversely, when the plunger 25 rises and the pressure in the pressurizing chamber 22 rises, the suction valve 26 closes. When the pressure pressurized in the pressurizing chamber 22 reaches a predetermined pressure, the discharge valve 27 is opened, and the high-pressure fuel pressurized in the pressurizing chamber 22 is discharged toward the common rail 2.

The ECU 5 is a CPU that performs control processing and arithmetic processing, a storage device (ROM, standby RAM or EEPROM, memory such as RAM) that stores various programs and data, an input circuit, an output circuit, a power supply circuit, an injector drive circuit, and a pump drive It is configured to include functions such as circuits. Various arithmetic processes are performed on the basis of sensors signals read by the ECU 5 (engine parameters: signals corresponding to the operating state of the occupant, the operating state of the engine 1, etc.).
As shown in FIG. 4, the sensors connected to the ECU 5 include an accelerator sensor 41 that detects the accelerator opening, a rotation speed sensor 42 that detects the engine rotation speed, and a water temperature that detects the cooling water temperature of the engine 1. Sensor 43, intake air temperature sensor 44 for detecting the intake air temperature sucked into engine 1, rail pressure sensor 45 for detecting the actual rail pressure, fuel temperature sensor 46 for detecting the fuel temperature supplied to injector 3, and other sensors There is class 47.

[Features of Example 1]
The drive current control of the SCV 14 by the ECU 5 will be described.
The ECU 5 is a feedforward control means (program: hereinafter referred to as F / F) that calculates a basic drive current value (Ibase) to be applied to the solenoid 24 of the SCV 14 in accordance with the operation state (value detected by each sensor). ) And F / B control means (program) for correcting the basic drive current value (Ibase) calculated by the F / F control means based on the differential pressure (deviation) between the target rail pressure and the actual rail pressure, and corrected A duty signal calculating means (program) for converting the drive current value (I) into a duty signal.

  The F / F control means calculates the pump discharge amount (fuel consumption = injector injection amount + leakage amount) from the engine speed (NE), the actual rail pressure, the commanded injection amount of the injector 3, the fuel temperature, etc., and the pump A basic drive current value (Ibase) corresponding to the discharge amount is obtained by a map or the like.

The F / B control means obtains the proportional term (Ip) and the integral term (Ii) based on the differential pressure between the target rail pressure corresponding to the operating state and the actual rail pressure detected by the rail pressure sensor 45, and this proportionality is obtained. The basic drive current value (Ibase) is corrected by the term (Ip) and the integral term (Ii).
The proportional term (Ip) is a correction current value proportional to the differential pressure between the target rail pressure and the actual rail pressure.
The integral term (Ii) is a correction current value corresponding to the product of the difference between the target rail pressure and the actual rail pressure and the passage of time, and the gain (α) is provided so as to vary depending on the operating state. ing. The variable control of the gain (α) will be described later.

On the other hand, the ECU 5 stores the integral term (Ii) as a learning value (Iq) when a predetermined learning condition is satisfied, and corrects the basic drive current value (Ibase) using the stored learning value (Iq). Learning means are provided.
That is, the drive current value (I) given to the solenoid 24 of the SCV 14 is
I = Ibase + Ip + Ii · α + Iq (1)
Is required.

  Next, referring to FIG. 1, the actual rail pressure (in the figure, rails) when foreign matter is caught in SCV 14 while engine 1 is stable, such as at idling, and then the foreign matter is removed. Pressure), SCV14 opening (SCV opening in the figure), drive current value (pump drive current I in the figure), proportional term (F / B proportional term Ip in the figure), integral term (F in the figure) / B integral term Ii), the time series change of the learning value (the learning value Iq in the figure) will be described.

  When a foreign object is caught in the SCV 14 (see a1 in the figure) and the opening of the SCV 14 increases (see a2 in the figure), oversupply of the supply pump 4 occurs and the actual rail pressure starts to rise ( (See a3 in the figure). As a result, in order to make the actual rail pressure coincide with the target rail pressure, the proportional term (Ip) and the integral term (Ii) change (see a4 in the figure), and the drive current value (I) is corrected (in the figure). A5). As a result, the actual rail pressure is corrected to the target rail pressure.

In this way, when the foreign matter is caught in the SCV 14 and the overpumping of the supply pump 4 occurs, the integral term (Ii) becomes a negative value (a value that reduces the discharge amount), and the learning condition is satisfied in that state. (Refer to a6 in the figure), the integral term (Ii) is converted into a learning value (Iq) (see a7 in the figure), and the integral term (Ii) is reset.
When restarting in a state where foreign matter is caught in the SCV 14, the learning value (Iq) before restarting is reflected in the driving current value (I). The rail pressure rises to the target rail pressure. As a result, the engine 1 can be started well when the engine 1 is restarted.

However, there is a possibility that the foreign matter caught in the SCV 14 is removed during operation of the engine 1 (see b1 in the figure), and then the engine 1 stops before the learning condition is satisfied.
When the engine 1 is started in such a state, the learning value (Iq) before the engine is stopped is reflected in the drive current value (I), even though the foreign matter caught in the SCV 14 is removed. Since the opening degree is suppressed (see b8 in the figure), even if cranking is performed for a long time, an increase in the actual rail pressure is suppressed. As a result, the cranking time at the time of restart becomes longer and the startability becomes worse.

Therefore, in the ECU 5 of the first embodiment, the cranking time (starter operating time) of the engine 1 is a predetermined time (for example, the average time from when the starter is turned on in the mounted vehicle model to completion of the complete explosion). After that, there is provided an integral gain correction means (program) for increasing the gain (α) of the integral term (Ii) described above.
Specifically, in the first embodiment, as shown in FIG. 2, when the cranking time (Tcr) of the engine 1 has passed a predetermined time, the gain (Ii) of the integral term (Ii) according to the cranking time (Tcr) ( It is provided to gradually increase α).

A control example of the integral gain correcting means will be described with reference to the flowchart of FIG.
When the ECU 5 is actuated (start), it is first determined whether or not the engine is being started (a cranking state in which the starter switch is turned on) (step S1). If the determination result in step S1 is NO, the process returns.
If the determination result in step S1 is YES, whether or not the rail pressure is below a certain value (for example, the state where the actual rail pressure detected by the rail pressure sensor 45 has not reached the target rail pressure calculated by the ECU 5). Is determined (step S2).

If the determination result in step S2 is YES, as shown in FIG. 2, the gain (α) corresponding to the cranking time (Tcr) is obtained from a map or the like (step S3). By controlling the step S3, the gain (α) of the integral term (Ii) can be gradually increased according to the cranking time (Tcr) when the cranking time (Tcr) of the engine 1 elapses a predetermined time. it can.
Subsequently, the drive current value (I) is calculated using the above-described equation (1), the drive current value (I) is given to the SCV 14 (step S4), and then the process returns.
If the determination result in step S2 is NO, it is not necessary to change the gain (α), the gain (α) is set to 1.0 (step S5), and then the process proceeds to step S4 described above.

The operation by providing the integral gain correction means will be described with reference to FIG. 1 again.
As described above, when the engine 1 is in operation, the foreign matter caught in the SCV 14 is removed (see b1 in the figure), and then when the engine 1 is stopped before the learning condition is satisfied, The learning value (Iq) before restart is reflected in the drive current value (I) and the opening degree of the SCV 14 is suppressed, even though the foreign matter caught in the SCV 14 is removed.

  However, when the cranking time (Tcr) at the time of start elapses a predetermined time, the gain (α) of the integral term (Ii) is increased by the integral gain correcting means (see the broken line c1 in the figure), and the drive given to the SCV 14 The current value (I) increases (see the broken line c2 in the figure). As a result, the opening of the SCV 14 at the start of the engine 1 is expanded (see the c3 broken line in the figure), the discharge capacity of the supply pump 4 is increased, and the actual rail pressure is increased (see the c4 broken line in the figure).

(Effect of Example 1)
As described above, even if the foreign matter caught in the SCV 14 is removed, the cranking of the engine 1 is performed even in a state where the learning value (Iq) in the state where the foreign matter is stuck is not returned. When the time (Tcr) elapses a predetermined time, the gain (α) of the integral term (Ii) is increased, so that the discharge capacity of the supply pump 4 is increased, the actual rail pressure is increased, and the startability can be improved. You can save time.
Further, even in a state where the viscosity of the fuel is increased due to a low temperature such as in the extremely cold season and the discharge capacity of the supply pump 4 is decreased, the gain (α) of the integral term (Ii) is increased to start the engine 1. The opening of the SCV 14 is widened, and the discharge capacity of the supply pump 4 is increased. As a result, even when the viscosity of the fuel is increased, the actual rail pressure can be increased, so that the startability can be improved and the start time can be shortened.

A second embodiment will be described.
The ECU 5 according to the first embodiment shows an example in which the drive current value (basic drive current value Ibase) calculated according to the driving state is corrected with the correction current value (proportional term Ip + integral term Ii).
On the other hand, the ECU 5 of the second embodiment obtains a pump discharge amount (basic pump discharge amount before calculating the drive current value) according to the operation state, and calculates the pump discharge amount as a proportional term (Ip) and an integral term. The correction is made at (Ii).

More specifically, the F / F control means calculates the pump discharge amount (injector injection amount + leakage amount) from the engine speed (NE), the actual rail pressure, the commanded injection amount of the injector 3, the fuel temperature, and the like.
The F / B control means obtains the proportional term (Ip) and the integral term (Ii) based on the differential pressure between the target rail pressure corresponding to the operating state and the actual rail pressure detected by the rail pressure sensor 45, and this proportionality is obtained. The pump discharge amount is corrected based on the term (Ip) and the integral term (Ii).
The proportional term (Ip) is a corrected discharge amount proportional to the differential pressure between the target rail pressure and the actual rail pressure.
The integral term (Ii) is a corrected discharge amount corresponding to the product of the difference between the target rail pressure and the actual rail pressure and the passage of time, and the gain (α) is obtained by the integral gain correcting means described in the first embodiment. , And increases according to the cranking time (Tcr).
Even if provided in this way, the same effect as in the first embodiment can be obtained.

[Modification]
In the above embodiment, when the cranking time (Tcr) elapses a predetermined time, the gain (α) increases proportionally. However, when the cranking time (Tcr) elapses the predetermined time, the gain is increased. The gain (α) may be increased by other means such as increasing (α) abruptly, stepwise, or increasing the increase rate as the cranking time (Tcr) becomes longer.
In the above embodiment, the normally closed SCV 14 in which the valve opening is fully closed when the energization of the solenoid 24 is stopped is shown as an example, but conversely, when the energization of the solenoid 24 is stopped, the valve is opened. A normally open type SCV 14 that is fully open may be used. In this case, when the drive current value of the solenoid 24 is increased, the opening degree of the SCV 14 is decreased. Therefore, the increase / decrease control of the drive current value of the solenoid 24 is performed in reverse to the above embodiment.

It is a time chart explaining the time series change of an actual rail pressure, the opening degree of SCV, a drive current value, a proportional term, an integral term, and a learning value. It is a graph which shows the relationship between cranking time and a gain (integral term correction coefficient). It is a flowchart which shows the example of control of an integral gain correction | amendment means. It is the schematic of a common rail type fuel injection device. It is sectional drawing of a supply pump. It is a graph which shows the relationship between a drive current value and the discharge amount (injection amount) of a supply pump. It is a time chart explaining the time series change of an actual rail pressure, the opening degree of SCV, a drive current value, a proportional term, an integral term, and a learning value.

Explanation of symbols

1 engine (internal combustion engine)
2 Common rail 3 Injector 4 Supply pump 5 ECU (control device programmed with functions of feedforward control means, feedback control means, integral gain correction means and learning means)
14 SCV (Suction metering valve)
22 Pressurizing chamber 24 Solenoid

Claims (4)

An injector for injecting high-pressure fuel stored in a common rail;
A supply pump for supplying high pressure fuel to the common rail;
An intake metering valve that adjusts the flow rate sucked into the pressurizing chamber of the supply pump by varying the drive current value applied to the solenoid, and adjusts the pressure of the common rail;
A control device comprising a feedforward control means for calculating a drive current value to be given to the solenoid according to an operating state of the internal combustion engine;
In a common rail fuel injection device comprising:
The controller is
A proportional term and an integral term are obtained based on a differential pressure between a target rail pressure corresponding to an operating state of the internal combustion engine and an actual rail pressure that is an actual pressure of the common rail, and the driving is performed based on the proportional term and the integral term. Feedback control means for correcting the current value;
Integral gain correction means for increasing the gain of the integral term when the cranking time of the internal combustion engine passes a predetermined time;
A common rail fuel injection device comprising: An injector for injecting high-pressure fuel stored in a common rail;
A supply pump for supplying high pressure fuel to the common rail;
An intake metering valve that adjusts the flow rate sucked into the pressurizing chamber of the supply pump by varying the drive current value applied to the solenoid, and adjusts the pressure of the common rail;
A control device that includes feedforward control means for calculating a pump discharge amount of the supply pump according to an operating state of the internal combustion engine, and that supplies a drive current according to the pump discharge amount to the solenoid;
In a common rail fuel injection device comprising:
The controller is
A proportional term and an integral term are obtained based on a differential pressure between a target rail pressure corresponding to an operating state of the internal combustion engine and an actual rail pressure that is an actual pressure of the common rail, and the pump is obtained based on the proportional term and the integral term. Feedback control means for correcting the discharge amount;
Integral gain correction means for increasing the gain of the integral term when the cranking time of the internal combustion engine passes a predetermined time;
A common rail fuel injection device comprising: In the common rail type fuel injection device according to claim 1 or 2,
The control device includes learning means for storing the integral term as a learning value when a predetermined learning condition is satisfied, and correcting the driving current value or the pump discharge amount using the stored learning value. A common rail fuel injection device. In the common rail type fuel injection device according to any one of claims 1 to 3,
The integral gain correcting means includes
A common rail fuel injection device, which is provided so as to gradually increase the gain of the integral term when a cranking time of the internal combustion engine passes a predetermined time.

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