JP2003269203A - Start control device of diesel engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the increase of HC in exhaust emission at the time of starting of a diesel engine 1 having a turbo-supercharger 30 connected to a rotary electric machine (turbo-motor 24). <P>SOLUTION: The turbo-motor 24 is operated by a motor at the time of starting of the engine 1 to supercharge intake air by the turbo supercharger 30 (SD2-5). The rotating speed nt of the turbo-motor 24 is controlled so that an intake pressure Pin exceeds a first set pressure Pin1 (SD3). When the intake pressure Pin exceeds a specified pressure Pin0, the EGR valve 35 is opened to recirculate exhaust emission. When the intake pressure Pin exceeds the first set pressure Pin1, the injection to supply fuel by injectors 5 for cylinders 2 is started. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a starting control device for a diesel engine equipped with a turbocharger, and more particularly,
The present invention relates to a turbocharger with a rotating electric machine attached to a turbine.

[0002]

2. Description of the Related Art Conventionally, as a diesel engine equipped with a turbocharger, for example, as disclosed in Japanese Unexamined Patent Publication No. 9-25828, a rotary electric machine mounted on a turbine is used as a motor or a motor depending on the operating state of the engine. It is known to operate as a generator. With this engine, the rotating electric machine is operated by a motor in the engine low speed range where the exhaust energy is small and the supercharging capacity of the turbocharger is low, and while the supercharging capacity is improved, the exhaust energy is large and the supercharging capacity is sufficient. When the above is obtained, the rotating electric machine is operated as a generator to recover the surplus exhaust energy.

[0003]

By the way, in general, a diesel engine burns fuel by self-ignition, so that the fuel is dispersed as much as possible by the flow of air sucked into the cylinder and mixed with air. It is desirable to promote the air utilization factor to promote a good combustion state with less exhaust gas harmful components.

However, when the engine is started, supercharging by the turbocharger is rarely performed until the combustion starts, so that the flow in the cylinder becomes extremely weak and the air utilization rate decreases. easy. Moreover, since the fuel supply amount is made relatively large in order to secure the startability, the air will be insufficient as a whole. For this reason, the concentration of unburned hydrocarbons (HC) in the exhaust gas temporarily increases rapidly, and soot may be generated, which is a problem.

The present invention has been made in view of the above circumstances, and an object of the present invention is to connect a rotary electric machine to a turbocharger of a diesel engine, and to connect the rotary electric machine at the time of starting the engine. It is to suppress the emission of harmful components (HC etc.) by devising the control procedure.

[0006]

In order to achieve the above object, in the present invention, the rotary electric machine is operated by a motor when the engine is started so that the turbocharger supercharges intake air.

[0007] Specifically, the invention of claim 1 is a starting control device for a diesel engine equipped with a turbocharger, the rotation control being connected so as to rotate in conjunction with a turbine of the turbocharger. An electric machine and a rotating electric machine control means for supercharging intake air by rotating the turbine by the rotating electric machine when the engine is started.

With the above construction, when the engine is started, the turbine of the turbocharger is rotated by the control of the rotary electric machine by the rotary electric machine control means, and the intake air is supercharged by the turbocharger. Therefore, even if the exhaust gas does not have effective energy before combustion starts in the cylinder of the engine, supercharging enhances the flow in the cylinder to promote the mixing of fuel and air, thereby improving the air utilization rate. It is possible to suppress the discharge of harmful components (HC and the like) as a good combustion state of high temperature.

According to a second aspect of the present invention, as the rotary electric machine control means, the supercharging pressure of intake air by the turbocharger is preset based on a value (eg, HC concentration) relating to the amount of a predetermined harmful component in the exhaust gas. It is assumed that the rotating electric machine is controlled so as to be equal to or higher than the set pressure of 1. Then, the first set pressure is
The effect of the invention of claim 1 is set in advance based on an experiment or the like so that the flow in the cylinder becomes sufficiently strong and a good combustion state is achieved, and the concentration of, for example, HC in the exhaust gas falls within an allowable range. Is sufficiently obtained.

According to a third aspect of the present invention, in the second aspect of the invention, there is provided fuel control means for starting fuel supply to the engine after the supercharging pressure of intake air becomes equal to or higher than a first set pressure when the engine is started. Be prepared. In this way, the fuel will be supplied only after the turbocharger has supercharged the intake air and the flow in the cylinder has become sufficiently strong, so that the emission of harmful components such as HC is further improved. It can be surely suppressed.

According to the fourth aspect of the present invention, an exhaust gas recirculation passage that connects the intake passage and the exhaust passage of the engine, an opening / closing valve that opens and closes the exhaust gas recirculation passage, and the opening / closing valve that is opened when the engine is started to recirculate exhaust gas. Exhaust gas recirculation control means for recirculating at least a part of exhaust gas to the intake passage through the passage.

As a result, at least a part of the exhaust gas once discharged from the cylinder is supplied to the cylinder again, and HC and the like contained therein are burned, so that the HC and the like is discharged from the engine. The amount can be further reduced.

According to a fifth aspect of the present invention, there is provided a variable valve mechanism according to the fourth aspect of the present invention, which is capable of changing at least one of the opening / closing timing and the lift amount of the intake valve of the engine, and the actual cylinder of the cylinder at the warm start of the engine. And a valve mechanism control means for operating the variable valve mechanism so that the compression ratio becomes relatively low. The actual compression ratio is a substantial compression ratio when the gas sucked into the cylinder before the intake valve of the cylinder is closed is compressed at the compression top dead center. Unlike the geometric compression ratio of
It is almost close to the ratio of the combustion chamber volume at the compression top dead center to the combustion chamber volume when the intake valve is closed.

With the above construction, at the time of warm starting of the engine, the variable valve mechanism is controlled by the valve mechanism controlling means to change at least one of the opening / closing timing and the lift amount of the intake valve of the engine. This substantially reduces the compression ratio of the cylinder. That is, for example, if the closing timing of the intake valve is set to a side that is significantly retarded from the bottom dead center of the cylinder, some of the gas in the cylinder will be blown back into the intake passage, so the actual compression of the gas The ratio is smaller than the geometric compression ratio of the cylinder. As a result, the pump work of the cylinder is reduced, the angular velocity variation of the crankshaft of the engine is reduced accordingly, and the vibration at the time of engine start is reduced.

On the other hand, if the actual compression ratio of the cylinder is lowered, the compression temperature of the cylinder is lowered, which may impair the ignitability. However, when the engine is warm-started, it recirculates into the cylinder. Since the temperature condition of the exhaust gas is higher than that of the outside air, the temperature condition of the intake air is raised by the recirculation of the exhaust gas, and the vaporization and atomization of the fuel spray is promoted, so that the ignitability is secured.

According to a sixth aspect of the present invention, the exhaust gas recirculation control means according to the fourth or fifth aspect of the present invention is opened and closed so that the amount of exhaust gas recirculated through the exhaust gas recirculation passage becomes a predetermined amount or more when the engine is warm started. The rotary electric machine control means controls the opening degree of the valve, and the rotary electric machine control means allows the supercharging pressure of the intake air by the turbocharger to recirculate the predetermined amount of exhaust gas to the intake passage.
It is assumed that the rotating electric machine is controlled so as to be equal to or lower than the set pressure of.

That is, since the downstream end of the exhaust gas recirculation passage is generally connected to the intake passage downstream of the blower of the turbocharger, if the supercharging pressure of intake air by the turbocharger is too high, It becomes difficult for the exhaust gas to flow back into the intake passage having such a high pressure state. Therefore, in the present invention, the supercharging pressure of the intake air by the turbocharger is set to be equal to or lower than the second set pressure, and the recirculation amount of the exhaust gas in the exhaust gas recirculation passage is set to a predetermined amount or more,
The effect of the invention of claim 4 or 5 can be sufficiently obtained.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(Overall Structure) FIG. 1 shows an example of a combustion control device A for a diesel engine according to an embodiment of the present invention, and 1 is a diesel engine mounted on a vehicle.
The engine 1 has a plurality of cylinders 2, 2, ... (Only one is shown), and a piston 3 is reciprocally fitted in each cylinder 2, and each cylinder 2 is fitted by the piston 3.
A combustion chamber 4 is defined inside. As shown in FIG. 2 in an enlarged manner, an injector 5 is provided on the ceiling of the combustion chamber 4, and an injection nozzle 5 integrally provided at the tip of the injector 5.
0 protrudes from a substantially central portion of the ceiling surface 40 of the combustion chamber 4 by a predetermined amount. On the other hand, a cavity 3a is formed on the top surface of the piston 3 which is the bottom of the combustion chamber 4, and in the vicinity of the compression top dead center of the cylinder 2, the injection nozzle 5 of the injector 5 is formed.
The fuel is radially injected from 0 to the inner peripheral wall of the cavity 3a positioned so as to surround the periphery.

Further, four intake / exhaust ports 41, 41, 42, 42 are formed so as to surround the injector 5 on all sides, and each of them is opened to face the combustion chamber 4.
Two of the intake ports 41, 41 (only one of which is shown) are curved and extend obliquely upward from the combustion chamber 4, and are open on one side surface of the engine 1 (right side surface in FIG. 1). On the other hand, the two exhaust ports 42, 42 merge into one on the way, and the other side surface of the engine 1 (the left side surface in FIG. 1)
Has been extended to. And each port 4 facing the combustion chamber 4
An intake valve 43 and an exhaust valve 44 are arranged at the open ends of 1, 42, ... To open and close them.

The intake valve 43 and the exhaust valve 44 are shown only in FIG.
The camshafts 45 and 46 of the book are timing belts (not shown)
By being rotationally driven by the crankshaft 8 via the, the opening / closing operation is performed at a predetermined timing for each cylinder 2 as schematically shown in FIG. That is, as shown by the solid line in the figure, basically, the closing timing EX of the exhaust valve 44 is
C is on the retard side with respect to the intake top dead center (TDC) of the cylinder 2, while the valve opening timing IO of the intake valve 43 is on the advance side with respect to TDC. It overlaps with the valve opening period of the valve 44. Further, the closing timing IC of the intake valve 43 is on the retard side with respect to the intake bottom dead center (BDC).

The intake side camshaft 45 has a known variable valve mechanism 47 (Valiable Valve T) for continuously changing the rotational phase with respect to the crankshaft 8 within a predetermined angle range.
iming: hereinafter, abbreviated as VVT) is attached, and the opening / closing timing of the intake valve 43 is changed by the operation of the VVT 47. This VVT47
Has a schematic structure as shown in FIG. 4, and includes a rotor 47a fixed to an end of the cam shaft 45, and a casing 47c arranged so as to cover the rotor 47a and fixed to a sprocket 47b. There is. The outer periphery of the rotor 47a is provided with four vanes protruding radially outward, while the inner periphery of the casing 47c is provided with four partition walls extending inward. A plurality of hydraulic working chambers 47d, 47 are provided between the vane and the partition wall.
are formed, and the oil pressure of the engine oil as the operating oil is adjusted by the oil control valve 47f (hereinafter, referred to as OCV).

More specifically, the hydraulic working chambers 47d, 4
.. are alternately divided into those on the advance side and those on the retard side in the circumferential direction, and when the oil pressure in the hydraulic operation chambers 47d, 47d ,. 47
a is rotated in a direction in which the cam shaft 45 rotates with respect to the casing 47c (indicated by an arrow in the figure), whereby the intake valve 4
The valve opening timing IO and valve closing timing IC of 3 shift to the advance side. On the other hand, on the contrary, the hydraulic working chambers 47e, 47e,
When the hydraulic pressure of ... Increases, the rotor 47a moves to the casing 4
7c, the cam shaft 45 is rotated in the opposite direction to the rotating direction, whereby the opening timing IO and closing timing of the intake valve 43 are increased.
IC shifts to the retard side. Due to the shift to the retard side, as shown by the phantom line in FIG. 3, the opening / closing timing I of the intake valve 43 is
O and IC are changed by about 20 ° at maximum.

As shown in FIG. 1, the injector 5 for each cylinder 2 is connected to a common fuel supply pipe 6 (common rail) by branch pipes 6a, 6a, ... (Only one shown). . The common rail 6 is connected to a high pressure supply pump 9 by a fuel supply pipe 8 and is in a high pressure state so that the fuel supplied from the high pressure supply pump 9 can be supplied to the injectors 5, 5, ... At any timing. A fuel pressure sensor 7 for detecting the fuel pressure (common rail pressure) inside the fuel pressure sensor 7 is provided. The high-pressure supply pump 9 is connected to a fuel supply system (not shown), and is drivingly connected to the crankshaft 10 by a toothed belt or the like to send the fuel under pressure to the common rail 6 and a part of the fuel through an electromagnetic valve. The amount of fuel supplied to the common rail 6 is adjusted by returning to the fuel supply system via the. The opening of the electromagnetic valve is controlled by the ECU 38 (described later) according to the value detected by the fuel pressure sensor 7, so that the fuel pressure is changed to the engine 1
Is controlled to a predetermined value corresponding to the operating state of.

A crank angle sensor 11 composed of an electromagnetic pickup for detecting the rotation angle (crank angle) of the crank shaft 10 is attached to the crank shaft 10, and a starter motor 12 is drivingly connected to the crank shaft 10. That is, the toothed pulley 10a is fixed to the end of the crankshaft 10,
A toothed belt (shown by a virtual line) is wound between the pulley 10a and the pulley of the starter motor 12, and an electromagnetic clutch is arranged between the drive shaft of the starter motor 12 and the pulley. However, the rotational force is transmitted or interrupted by the operation of this clutch. Although not shown, the starter motor 12 is
It is connected to a large-capacity battery via a control circuit having an inverter and the like, and operates a motor that receives electric power from the battery to drive the crankshaft 10, and a generator that is rotated by the crankshaft 10 to generate electricity. It can be switched to operation. Furthermore, engine 1
A cam angle sensor (not shown) that detects the rotation angle of the intake-side cam shaft 45 and an engine water temperature sensor 13 that detects the temperature of engine cooling water are provided in the engine.

An intake passage 16 for supplying the air (fresh air) filtered by the air cleaner 15 to the combustion chamber 4 of each cylinder 2 is connected to one side surface (right side in the drawing) of the engine 1. . A surge tank 17 is provided at the downstream end of the intake passage 16, and each of the passages branched on the downstream side communicates with the combustion chamber 4 of each cylinder 2 through an intake port 41. Further, the surge tank 17 is provided with an intake pressure sensor 18 for detecting the pressure state of intake air.

The intake passage 16 is driven by a hot film type air flow sensor 19 for detecting the flow rate of air sucked into the engine 1 from the outside in order from the upstream side to the downstream side, and a turbine 27 described later. A blower 20 for compressing the intake air is provided, an intercooler 21 for cooling the intake air compressed by the blower 20, and an intake throttle valve 22 formed of a butterfly valve. The intake throttle valve 22 has its valve shaft rotated by a stepping motor 23 to be in an arbitrary state from fully closed to fully open. Even in the fully closed state, the intake throttle valve 22 and the intake passage 16 are not closed. It is configured so that a gap is left between the peripheral wall and air to flow in.

On the other hand, an exhaust passage 26 is connected to a side surface on the opposite side (left side in the drawing) of the engine 1 so as to exhaust combustion gas (exhaust gas) from the combustion chamber 4 of each cylinder 2. An upstream end portion of the exhaust passage 26 is an exhaust manifold that branches for each cylinder 2 and communicates with the combustion chamber 4 through an exhaust port 42. The exhaust passage 26 downstream of the exhaust manifold has an upstream side to a downstream side. In order towards the side,
A turbine 27 that receives the exhaust flow and is rotated, and a catalytic converter 28 that can purify harmful components (HC, CO, NOx, soot, etc.) in the exhaust are provided.

The turbocharger 30 including the turbine 27 and the blower 20 in the intake passage 16 changes the cross-sectional area (nozzle cross-sectional area) of the exhaust passage to the turbine 27 by the movable flaps 31, 31, .... Is a variable turbo (hereinafter referred to as VGT) that is adapted to
1, ... are respectively drivingly connected to the diaphragm 32 via a link mechanism (not shown), and the diaphragm 32
Is adjusted by a solenoid valve 33 for controlling the negative pressure, the rotational position of the flaps 31, 31, ... Is adjusted, and the nozzle cross-sectional area is changed. ing.

A motor 24 (rotary electric machine: hereinafter referred to as a turbo motor) is attached to the turbocharger 30 so as to rotate in association with the turbine 27. As shown in an enlarged view in FIG. 5, the turbo motor 24 includes a rotor 24 a that is connected to the rotating shafts of the turbine 27 and the blower 20 so as to rotate integrally, and a turbocharger 30.
And a stator 24b fixed to the casing 30a, and a position sensor 24c for detecting the rotation angle of the rotor 24a is attached to the casing 30a. Further, the turbo motor 24 is connected to a battery (not shown) via a control circuit 25 having an inverter or the like, and the turbo motor 24 is connected to the battery according to a change in the frequency of the alternating current applied from the control circuit 25 to the stator 24b. The operation of the motor for driving the turbocharger 30 by receiving the electric power of the above is switched to the operation of the generator for rotating the turbocharger 30 to generate electric power.

In the exhaust passage 26, the turbine 2
An upstream end of an exhaust gas recirculation passage (hereinafter referred to as an EGR passage) 34 that recirculates a part of the exhaust gas to the intake side is connected so as to branch from a portion on the exhaust gas upstream side of 7. This EGR
The downstream end of the passage 34 is connected to the intake throttle valve 22 and the surge tank 1.
7 is connected to the intake passage 16 and is connected to the exhaust passage 26.
A part of the exhaust gas taken out from the exhaust gas is recirculated to the intake passage 16. An exhaust gas recirculation amount control valve (hereinafter referred to as E) whose opening degree can be adjusted is provided near the downstream end in the middle of the EGR passage 34.
A GR valve) 35 is arranged. This EGR valve 3
Reference numeral 5 is a negative pressure responsive type, and like the flaps 31, 31, ... Of the VGT 30, the magnitude of the negative pressure to the diaphragm is adjusted by the solenoid valve 36, so that the EG
The passage cross-sectional area of the R passage 34 is adjusted linearly to adjust the flow rate of the exhaust gas recirculated to the intake passage 16.

The injectors 5, high pressure supply pump 9, intake throttle valve 22, VGT 30, EGR valve 35, etc.
Both are control units (Electronic Contorol
It operates by receiving a control signal from a unit (hereinafter referred to as ECU) 38. On the other hand, at least output signals from the fuel pressure sensor 7, the crank angle sensor 11, the cam angle sensor, the engine water temperature sensor 13, the intake pressure sensor 18, the air flow sensor 19, the position sensor 24c, etc. are input to the ECU 38, Further, output signals from a vehicle speed sensor 37 (not shown) that detects the traveling speed of the vehicle and an accelerator opening sensor 39 that detects the amount of accelerator pedal depression (accelerator opening) of the vehicle are input. .

Then, the engine 1 by the ECU 38
As a basic control during the operation of, the target fuel injection amount is mainly determined based on the accelerator opening degree, the fuel injection amount and the injection timing are controlled by the operation control of the injector 5, and the high pressure supply pump 9 is controlled. The operation controls the fuel pressure, that is, the injection pressure of the fuel amount. Further, the recirculation ratio of the exhaust gas to the combustion chamber 4 is controlled by controlling the operation of the intake throttle valve 22 and the EGR valve 35, and the supercharging efficiency of the intake air is controlled by controlling the operation of the flaps 31, 31, ... Of the VGT 30. Is trying to improve.

Further, in this embodiment, the operation of the engine 1 is automatically stopped (so-called idle stop) or automatically restarted under a predetermined condition. Starter motor 1 by
A control signal is output to the control circuit of No. 2 and the starter motor 1
2, the crankshaft 10 is rotated, and a control signal is output from the ECU 38 to the control circuit 25 of the turbo motor 24, which will be described in detail later.
Thus, the turbocharger 30 is operated to supercharge the intake air.

(Engine Start Control) Next, as a feature of the present invention, a specific control procedure of the engine 1, the starter motor 12, and the turbo motor 24, mainly at the time of starting, will be described in detail with reference to FIGS. Explained.

First, in the flow of the fuel injection control shown in FIG. 6, in step SA1 after the start, the fuel pressure sensor 7, the crank angle sensor 11, the cam angle sensor, the engine water temperature sensor 13, the intake pressure sensor 18, the air flow sensor 1 are detected.
9, the output signals from the vehicle speed sensor 37, the accelerator opening sensor 39, etc. are input, respectively, and the value of the ignition determination flag F (described later) is read from the memory of the ECU 38 (data input). Then, in step SA2, the target torque Trq is read from the target torque map electronically stored in the memory of the ECU 38 based on the accelerator opening Acc and the vehicle speed V (setting of the target torque). For example, as shown in FIG. 7A, the target torque map is set so that the target torque Trq increases as the accelerator opening Acc increases and the vehicle speed V increases.

Subsequently, in step SA3, it is determined whether or not the engine 1 is being started. This is because, for example, the target torque Trq is not set value Trq0 ≈ 0 where Trq>Trq> Trq
q0) And when the engine 1 is not ignited, it is at the time of starting Y
If it is determined to be ES, the process proceeds to step SA4, and if not, it is determined to be NO when the engine is not started, and step S to be described later.
Proceed to A10. That is, for example, when the accelerator pedal is depressed while the vehicle is stopped and the engine 1 is not ignited, it is determined that the engine 1 is started. At this time, the fact that the engine 1 has not been ignited means that an ignition determination flag F described later is used.
It judges based on the value of. Then, in step SA4 which is judged as YES when the engine is started, the control amount Mt of the starter motor 12 is set. This is because a basic control amount Mtb is read from a table (not shown) preset based on the target torque Trq, is output to the control circuit of the starter motor 12, and is also based on the signal from the crank angle sensor 11. Feedback correction. That is, in step SA5, a control signal is output to the control circuit of the starter motor 12, and electric power is supplied to the starter motor 12 from this circuit to drive the crankshaft 8
To rotate (motor operation).

Then, in step SA6, the intake pressure P
It is determined whether in (supercharging pressure) is equal to or higher than the first set pressure Pin1. That is, as will be described in detail later, when the engine 1 is started, the turbo motor 24 is operated to supercharge the intake air by the turbocharger 30, and the intake pressure Pin rises due to this supercharging. But the intake pressure P
While in is less than the first set pressure (judgment is NO), the routine returns to step SA1, while if the intake pressure Pin is equal to or higher than the first set pressure (judgment is YES: Pin ≧ Pin1), the routine proceeds to step SA7. Then, the target injection amount Q of fuel and the target injection timing IT are set. The fuel injection amount Q and the target injection timing IT are set by reading the corresponding values at the time of starting from maps (see FIGS. 7 (b) and (c): described later) that are electronically stored in the memory of the ECU 38. Just do it.

Then, in step SA8, it is determined that the set injection timing IT has been reached for each of the cylinders 2, 2, ... Of the engine 1 and waits until this injection timing IT is reached (determination is NO), If the injection timing IT is reached (determination is YES)
In step SA9, a control signal is output to the injector 5 (injection execution). Then, in step SA10, the ignition determination of the engine 1 is performed, and then the process returns.

That is, when the engine 1 is started, the intake pressure Pin becomes equal to or higher than the first set pressure due to supercharging, and the intake flow in the cylinder 2 becomes sufficiently strong so that the fuel supply is started for the first time. ing. In other words, the first set pressure Pin1 is such an intake pressure Pin that is set in advance based on an experiment.

Further, the above-mentioned ignition determination (step SA1
0), as described above, the engine 1
When the crankshaft 8 is driven by the starter motor 12 at the start of
The electric power supplied to the starter motor 12 is feedback-controlled so that the detected value becomes a predetermined value. Therefore, when the engine 1 ignites and starts to rotate by itself, the starter motor 1
The power supplied to No. 2 is significantly reduced, and the ignition can be determined based on this. When it is determined that ignition has occurred, the ignition determination flag F is turned on (F ← 1).

When the start of the engine 1 is completed in this way, it is determined in step SA3 based on the value of the ignition determination flag F that it is NO when the engine 1 is not started. At this time, therefore, the routine proceeds to step SA11. , It is determined whether or not the vehicle is decelerating. That is, for example, when the vehicle speed V is decreasing, is greater than the set vehicle speed V1, and the target torque Trq is substantially zero (Trq =
Trq0), while the vehicle is decelerating, it is determined to be YES and proceeds to step SA12, and otherwise, it is determined to be NO and proceeds to step SA14. Then, in step SA12 which is determined as decelerating as described above, the control amount to the control circuit of the starter motor 12 is controlled according to the vehicle speed V and the battery charge amount so that the starter motor 12 is operated by the generator due to the running inertia of the vehicle. Mt is set, and in step SA13 that follows, the starter motor 12 is operated as a generator to convert the kinetic energy of the vehicle into electrical energy and store it in a battery (energy regeneration). Then, the injector 5 does not inject the fuel and returns.

That is, the injector 5 is used when the vehicle is decelerating.
Fuel injection is stopped (fuel cut), and energy is regenerated while applying a braking force to the vehicle by the operation of the starter motor 12 as a generator. The reason why the energy regeneration is limited when the vehicle speed V is higher than the set vehicle speed V1 is in consideration of the driving feeling.

On the other hand, if the vehicle is not decelerating in step SA11, the determination is NO and the operation proceeds to step SA14.
Then, next, whether to make the engine 1 a normal operating state,
Alternatively, it is determined whether the idle stop should be performed. That is,
When the target torque Trq is substantially zero (Trq = Trq0) and the vehicle speed V is less than or equal to the set vehicle speed (V ≦ V1), it is determined that the idle stop is YES and fuel injection by the injector 5 is not performed, and ignition is determined. Turn off the flag F (step SA
15: F ← 0), and returns.

In step SA14, the target torque Trq is not substantially zero (Trq> Trq0) or the vehicle speed V
Is determined to be greater than the set vehicle speed V1 (V> V1),
In step SA16, the target injection amount Q of fuel and the target injection timing IT for normal operation control are set. The target fuel injection amount Q is set based on the operating state (target torque Trq and engine speed ne) of the engine 1 from the fuel injection amount map electronically stored in the memory of the ECU 38. It is sufficient to read Qb and correct it according to the intake pressure, engine water temperature, and the like. In the fuel injection amount map illustrated in FIG. 7B, the injection amount Qb
Is set to a larger value as the target torque Trq is larger and the engine rotation speed ne is higher.

Further, the target injection timing IT may be set based on the injection timing map as illustrated in FIG. 7 (c) as well. In this map, the injection timing IT is set to a value on the advance side as the target torque Trq is larger and the engine speed ne is higher. Then, in step SA17, the injection timing IT set above is set for each cylinder 2, 2, ... Of the engine 1.
When the injection timing IT is reached (the determination is YE, the determination is NO).
S) Proceed to step SA18, output a control signal to the injector 5 (execute injection), and then return.

That is, the engine 1 is automatically stopped under a predetermined condition, that is, when the target torque Trq of the engine 1 is a set value (Trq0) of substantially zero and the vehicle is stopped or is about to stop, and thereafter, for example, When the accelerator pedal is depressed and the target torque Trq becomes large, the engine 1 is automatically started. Then, the control procedure of steps SA3 to SA10 in the flow shown in FIG. 6 constitutes the start control section 38a for automatically starting the engine 1, and the control procedure of steps SA14 and SA15 is performed under predetermined conditions. A stop controller 38b that automatically stops the engine 1 is configured.

(VVT Control) Next, V by the ECU 38
The control procedure of the VT 47 will be specifically described based on the flowchart of FIG. 8. First, in step SB1 after the start, the crank angle sensor 11, the cam angle sensor, the engine water temperature sensor 13, the vehicle speed sensor 37, the accelerator opening sensor. Output signals from 39 and the like are input, and the value of the ignition determination flag F is read from the memory of the ECU 38. In the following step SB2, the process shown in FIG.
Similar to step SA3 of the fuel injection control flow shown in, it is determined whether or not the engine 1 is being started. This judgment is YE
If it is S, the process proceeds to step SB6 described later, while if the determination is NO, the process proceeds to step SB3, where it is determined whether or not the vehicle is decelerating as in step SA11 of the fuel injection control flow. If this determination is YES, the process proceeds to step SB6, which will be described later, whereas if the determination is NO, the process proceeds to step SB4, where it is determined whether or not the idle stop is to be performed as in step SA14 of the fuel injection control flow. If the determination is YES, the process proceeds to step SB6, while if the determination is NO, the step S6 is performed.
Go to B5.

In step SB5, the operating state of the engine 1 (target torque Trq and engine speed n) is calculated from the valve timing map electronically stored in the memory of the ECU 38.
The target value VT of the closing timing of the intake valve 43 corresponding to e) is read. In this valve timing map, as shown in an example in FIG. 9, the valve closing timing VT of the intake valve 43 is set to be retarded as the target torque Trq is higher and the engine speed ne is higher. Has been done. On the other hand, in step SB6, the target value VT of the closing timing of the intake valve 43 is set to the set value VT1 on the relatively retarded side (shown by a virtual line on the map of FIG. 9). Then, in step SB7, a control signal for operating the VVT 47 so that the closing timing of the intake valve 43 becomes the target value VT is output to the OCV 47f, and this OCV 4
7 is duty-operated (VVT operation), and then the process returns.

The set value VT1 on the retard side of the closing timing of the intake valve 43 is such that a part of the intake air temporarily sucked into the cylinder 2 during the opening of the intake valve 43 is the intake port 41 path. Is set to such a value that the efficiency of charging the intake air into the cylinder 2 is reduced due to the blowback to the cylinder 2 and thereby the compression ratio of the cylinder 2 is substantially reduced. As a result, even if the turbocharger 30 is used to supercharge intake air when the engine 1 is started, the compression work of the cylinder 2 does not increase so much, and therefore the angular velocity fluctuation of the crankshaft 10 is excessively large. Therefore, it is possible to prevent excessive vibration from being generated at the time of starting.

Step SB2 of the flow shown in FIG.
4. In order to reduce the actual compression ratio of the cylinder 2 at the time of starting the engine 1 by the starter motor 12, decelerating the engine 1 or idling the engine 1 by the control procedure of SB6, the intake valve 43 of the intake valve 43 is reduced. A VVT control unit 38c (valve operating mechanism control means) that operates the VVT 47 is configured such that the valve closing timing is relatively retarded.
The VVT control unit 38c may be configured to control the operation of the VVT 47 as described above only when the engine 1 is started or particularly when it is warm started.

(Control of intake throttle valve 22 and EGR valve 35) Next, the intake throttle valve 22 and EGR by the ECU 38
A specific control procedure of the valve 35 will be described with reference to the flowchart of FIG.

First, in step SC1 after the start, the crank angle sensor 11, the engine water temperature sensor 13,
Output signals from the vehicle speed sensor 37, the accelerator opening sensor 39, etc. are input, and the value of the ignition determination flag F is read from the memory of the ECU 38. Then, step S
At C2, it is determined whether or not the engine 1 is being started, as in step SA3 of the fuel injection control flow shown in FIG. If the determination is NO, the process proceeds to step SC9 described later, while if the determination is YES, the process proceeds to step SC3 to determine whether the intake pressure Pin (supercharging pressure) is equal to or lower than the predetermined pressure Pin0. If this determination is YES (Pin ≦ Pin0), the routine proceeds to step SC4, where the target value EGR of the opening degree of the EGR valve 35
Is set to the first set opening EGRi that is close to full closure, but the determination is NO.
If so (Pin> Pin0), the process proceeds to step SC5, where EG
Set the target value EGR of the opening of the R valve 35 to the second set opening EGRs> EGRi
And The second set opening degree EGRs is such that the EGR valve 35 is in an open state closer to full open than in full close (for example, 4/5 to full open state).
2/3).

Subsequently, in step SC6, the control target value is set so that the intake throttle valve 22 is brought into an open state closer to full open than full close (for example, about 4/5 to 2/3 of full open state).
Tv is set (Tv = tv1), and the solenoid valve 3 of the diaphragm of the EGR valve 35 is controlled by the ECU 38 in step SC7.
A control signal is output to 6 (operation of the EGR valve), and in the subsequent step SC8, the ECU 38 outputs a control signal to the stepping motor 23 of the intake throttle valve 22 (operation of the intake throttle valve), and then returns.

That is, when the engine 1 is started, the intake pressure Pin
When the pressure exceeds a predetermined pressure Pin02, the EGR valve 35 is relatively opened so that the EGR passage 34 recirculates exhaust gas in a predetermined amount or more. By doing this, cylinder 2,
At least a part of the exhaust gas once discharged from the cylinders 2, ... Is again supplied to the cylinders 2, 2 ,.
C etc. will burn. Moreover, since the temperature of the exhaust gas is higher than that of the outside air when the engine 1 is warm, the temperature condition of the intake air becomes high due to the recirculation of the exhaust gas, the vaporization and atomization of the fuel spray is promoted, and the ignitability is improved. To do.

While the intake pressure Pin is equal to or less than the predetermined value Pin0,
The opening degree of the EGR valve 35 is made small in order to prevent the intake air supercharged by the turbocharger 30 from flowing out to the exhaust passage 26 via the EGR passage 34. The operation efficiency of 24 can be improved.

On the other hand, in step SC2, step SC which is judged to be NO when the engine 1 is not started and proceeds to step SC
At 9, it is determined whether or not the vehicle is decelerating, as in step SA11 of the fuel injection control flow. If the determination is NO, the process proceeds to step SC12, which will be described later, while if the determination is YES, the process proceeds to step SC10 to set the target value EGR of the opening degree of the EGR valve 35 to the substantially fully opened third set opening degree EGRr, and subsequently. , Go to steps SC6 to SC8, and
By operating the GR valve 35 and the intake throttle valve 22, respectively,
Then return.

That is, at the time of deceleration of the vehicle, the intake throttle valve 22 is opened in the same manner as at the time of starting the engine so that the pump work of the engine 1 is suppressed from increasing. Since the engine brake is relieved, the energy recovery efficiency by the generator operation of the starter motor 12 can be improved.

At step SC11, which has been judged as NO when the vehicle is not decelerating at step SC9, it is judged whether or not the engine is idling at this time, similarly to step SA14 of the fuel injection control flow. If the determination is NO, the process proceeds to step SC13, while the determination is Y.
If it is ES, the process proceeds to step SC12 and the EGR valve 35
The target value EGR of the opening of is set to the first set opening EGRi of substantially fully closed,
The routine proceeds to steps SC6 to SC8 to operate the EGR valve 35 and the intake throttle valve 22, respectively, and then returns.

Further, in step SC11, the process proceeds to step SC which is judged to be NO, which is not the idle stop.
At 13, the E corresponding to the operating state of the engine 1 is calculated from the EGR map electronically stored in the memory of the ECU 38.
The target value EGR of the opening degree of the GR valve 35 is read. In this map, as shown in FIG. 11A, as the target torque Trq is larger and the engine speed ne is higher, the EG
The opening degree of the R valve 35 is set to be small. Then, in step SC14, the target value Tv of the opening degree of the intake throttle valve 22 corresponding to the operating state of the engine 1 is read from the table electronically stored in the memory of the ECU 38. In this table, as shown in FIG. 11B, the opening of the intake throttle valve 22 is set to gradually increase as the engine speed ne increases. Then, the process proceeds to steps SC7 and SC8 to drive the EGR valve 35 and the intake throttle valve 22, respectively, and then returns.

Step SC of the flow shown in FIG.
5, the EGR control unit 38d (exhaust gas recirculation control means) is configured to open the EGR valve 35 relatively large at the time of starting the engine 1 to recirculate exhaust gas of a predetermined amount or more into the intake passage 16 by the control procedures of 5 and SC7. ing.

(Control of Turbo Motor) Next, the ECU 38
The control procedure of the turbo motor 24 according to the above will be specifically described based on the flowchart of FIG.
In step SD1 after the start, the crank angle sensor 11, the engine water temperature sensor 13, the position sensor 2
4c, the vehicle speed sensor 37, the output signal from the accelerator opening sensor 39, etc., respectively, and the value of the ignition determination flag F is read from the memory of the ECU 38. In the following step SD2, it is determined whether or not the engine 1 is being started, as in step SA3 of the fuel injection control flow shown in FIG. If this determination is YES, step SD3
The target value of the rotation speed nt (turbo rotation speed) of the turbocharger 30 is set to a preset value nts (see FIG. 13 described later).
(Indicated by a virtual line on the map). This target value nts
Is when the supercharging pressure Pin is the first set pressure Pin when the engine 1 is started.
It is set based on experiments in advance so that the flow rate in the cylinder 2 becomes sufficiently strong when it becomes 1 or more, and the concentration of harmful components (for example, HC) in the exhaust gas falls below the allowable range by good combustion. is there.

On the other hand, if the determination in step SD2 is NO, the process proceeds to step SD4, in which the operating state of the engine 1 (target torque Trq and engine speed n) is determined from the turbo map electronically stored in the memory of the ECU 38.
Read the target value of turbo rotation speed nt corresponding to e).
In this map, the rotational speed of the turbocharger 30 is preliminarily tested so that the total operating efficiency of the engine 1 main body and the turbocharger 30 is maximized according to the operating state of the engine 1. As shown in an example in FIG. 13, the target turbo rotation speed nt is set to be higher as the target torque Trq is larger and the engine rotation speed ne is higher. .

Then, in step SD5, a control signal is output to the control circuit 25 of the turbo motor 24 so that the rotational speed nt of the turbocharger 30 becomes the target value set in step SD3 or step SD4, Electric power is supplied from the control circuit 25 to the turbo motor 24 to rotate the blower 20 of the turbocharger 30 (operation of the turbo motor), and then the process returns. At this time, the rotation speed of the turbo motor 24 (the rotation speed nt of the turbocharger 30) is detected based on the signal from the position sensor 24c,
In response to this, the frequency of the alternating current applied from the control circuit 25 to the turbo motor 24 is feedback-corrected.

That is, while the engine 1 is in operation, the turbo motor on the low speed and low load side where the exhaust gas energy tends to be insufficient so that the total operation efficiency of the engine 1 main body and the turbocharger 30 is maximized. Motor the 24,
While improving the supercharging ability of the turbocharger 30, on the high speed side or the high load side where the exhaust energy is large and a sufficient supercharging ability is obtained, the turbo motor 24 is operated to generate a surplus exhaust energy. I have to.

Further, when the engine 1 is started, the turbocharger 30 is driven by the turbomotor 24, and the intake pressure Pin is raised to the first set pressure Pin1 or more by supercharging to sufficiently enhance the intake flow in the cylinder 2. By doing so, it is possible to realize a good combustion state, but if the intake pressure Pin is too high, the recirculation amount of the exhaust gas cannot reach a predetermined amount or more, so the target value nts of the turbo rotation speed nt. Is the second set pressure Pin at which the intake pressure Pin can recirculate exhaust gas at a predetermined amount or more.
It is preferable to set it to be 2 (Pin2> Pin1) or less.

Step SD of the flow shown in FIG.
According to the control procedure of 2, SD3, SD5, the turbine 2 is driven by the operation of the turbo motor 24 when the engine 1 is started.
A turbo motor control unit 38e (rotating electric machine control means) that rotates 7 to supercharge intake air by the turbocharger 30 is configured.

Next, automatic stop and restart of the diesel engine 1 according to this embodiment will be described with reference to the time chart of FIG. First, while the vehicle is traveling, the accelerator pedal is closed and fuel injection by the injector 5 is stopped (fuel cut). As a result, the vehicle speed V decreases and it is determined that the vehicle is decelerating (t = t
0), the EGR valve 35 is substantially fully opened by the EGR control unit 38d of the ECU 38, and the intake throttle valve 22 is also opened relatively large. In addition, the VVT control unit 38
By controlling the operation of the VVT 47 by c, the closing timing of the intake valve 43 is greatly retarded, and the cylinder 2 of the engine 1
The actual compression ratio of 2, ... Is lower than the geometrical value. As a result, the pump work of the engine 1 becomes small,
Since the effectiveness of the engine brake is reduced, the kinetic energy of the vehicle is effectively transmitted to the starter motor 12 that operates the generator, and the energy recovery efficiency is improved.

When the vehicle speed V drops below the set vehicle speed V1 (t = t1), it is determined that the vehicle is idling and the EGR control unit 38d closes the EGR valve 35 to a substantially fully closed state, after which the vehicle is stopped. Then (t = t2), the operation of the engine 1 is automatically stopped.

Then, when the accelerator pedal is depressed (t = t3), the crankshaft 10 of the engine 1 is driven by the starter motor 12, and the driving force of the starter motor 12 is transmitted to the wheels via the transmission. , The turbocharger 3 is driven by the turbo motor 24 as the vehicle starts.
0 is activated, intake air is supercharged, and intake pressure Pin (supercharging pressure)
Quickly rises. At this time, the EGR valve 35 is kept in a substantially closed state, and the supercharged intake air flows into the EGR passage 34.
Since it is possible to prevent the gas from flowing out to the exhaust passage 26 via the, the operating efficiency of the turbo motor 24 is improved. Also, at this time, the closing timing of the intake valve 43 is still largely retarded, which reduces the pump work of the cylinders 2, 2, ..., The driving force of the starter motor 12 is reduced. In addition to being effectively transmitted to the wheels, the vibration of the engine 1 does not become so large even when the engine speed ne is extremely low, and the engine speed ne rises quickly.

When the intake pressure Pin exceeds the predetermined pressure Pin0 (t = t4), the EGR valve 35 is greatly opened and a large amount of high-temperature exhaust gas flows into the intake passage 16 and the cylinders 2, 2 and 2 together with the outside air. Is supplied to the intake pressure P.
When in becomes equal to or higher than the first set pressure Pin1 (t = t5), injection and supply of fuel by the injector 5 is started, and the engine 1 starts to rotate by ignition combustion of this fuel spray (start of the engine 1). .

At this time, the intake pressure Pin is increased by supercharging and the intake flow in the cylinder 2 is sufficiently strengthened, so that the fuel is dispersed relatively widely in the cylinder 2 and the mixing with the air is promoted. As a result, the air utilization rate can be increased, and as a result, the concentration of HC and the like in the exhaust gas can be suppressed within the allowable range in a favorable combustion state. Further, as described above, even if the closing timing of the intake valve 43 is retarded and the actual compression ratio of the cylinders 2, 2, ... The vaporization and atomization of the fuel spray is promoted, which also leads to good flammability.

When the engine 1 is completely started,
After that, the opening degrees of the intake throttle valve 22 and the EGR valve 35 are controlled according to the operating state of the engine 1, and the operation control of the VVT 47 is performed so that the opening / closing timing of the intake valve 43 returns to the advance side. Further, the starter motor 12 stops the power transmission with the crankshaft 10 and stops immediately.

Therefore, according to the startability control apparatus A for the diesel engine according to this embodiment, first, the turbo motor 24 is operated by the motor when the engine 1 is started, and the turbocharger 30 supercharges intake air. In order to obtain a good combustion state in which the intake air is effectively supercharged to sufficiently enhance the flow in the cylinder 2 even when the exhaust gas does not have effective energy and the discharge amount of harmful components such as HC is small. You can

Moreover, since the fuel supply to the engine 1 is started only after the intake pressure Pin becomes equal to or higher than the first set pressure Pin1 due to supercharging, the discharge of HC and the like can be suppressed more reliably.

Further, at this time, since the EGR valve 35 is opened wide so that the exhaust gas of a predetermined amount or more is recirculated to the intake passage 16, the HC in the exhaust gas is reburned to further increase the exhaust amount thereof. In addition to being able to reduce the amount of fuel, the high temperature exhaust gas recirculation promotes the atomization and atomization of the fuel to further improve its combustibility.

Further, at that time, the compression ratio of the cylinder 2 can be substantially reduced by significantly retarding the closing timing of the intake valve 43 by the operation of the VVT 47, and as a result, as described above. Even if the turbocharger 30 is used to supercharge the intake air, the increase in the compression work of the cylinder 2 is suppressed,
It is possible to prevent an increase in engine vibration.

The structure of the present invention is not limited to that of the above-described embodiment, and includes various other structures. That is, the engine 1 of the above embodiment is provided with the VVT 47 that advances or retards the opening timing and the closing timing of the intake valve 43 in synchronization with each other as a variable valve mechanism.
The present invention is not limited to this, and although not shown, for example, a cam shaft 45 on the intake side may be provided with a switch for changing the working angle of the cam with respect to the intake valve 43. Alternatively, an electromagnetic valve mechanism that opens and closes the intake valve 43 directly by an electromagnetic solenoid or the like without using the camshaft 45 is provided, and the opening / closing timing of the intake valve 43 is changed by controlling energization of the electromagnetic solenoid. You may do it.

[0079]

As described above, according to the starting control device for a diesel engine according to the first aspect of the present invention, in a turbocharger to which a rotary electric machine is connected, the rotary electric machine is driven by a motor when the engine is started. By operating the turbocharger to supercharge the intake air, even when the exhaust gas does not have effective energy at the start, the supercharging of the intake air strengthens the flow in the cylinder to generate fuel. It is possible to promote the mixing with air and suppress the discharge of harmful components (HC and the like) in a good combustion state with a high air utilization rate.

According to the second aspect of the present invention, the concentration of, for example, HC in the exhaust can be kept within the allowable range by setting the supercharging pressure of intake air to be equal to or higher than the first set pressure when the engine is started.
The effect of the invention of claim 1 is sufficiently obtained.

According to the third aspect of the present invention, the fuel supply to the engine is started for the first time after the supercharging pressure becomes equal to or higher than the first set pressure and the flow in the cylinder becomes sufficiently strong.
The discharge of harmful components such as C can be suppressed more reliably.

According to the fourth aspect of the present invention, the exhaust gas is recirculated when the engine is started, so that the HC and the like in the exhaust gas can be re-combusted, and the exhaust amount thereof can be further reduced.

According to the fifth aspect of the present invention, at the time of warm starting of the engine, the vibration can be reduced by changing the opening / closing timing of the intake valve or the like to substantially reduce the compression ratio of the cylinder. Moreover, the ignitability can be ensured by raising the intake air temperature by recirculating the exhaust gas having a temperature higher than that of the outside air.

According to the sixth aspect of the present invention, the intake supercharging pressure by the turbocharger is set to be equal to or lower than the second set pressure so that exhaust gas of a predetermined amount or more can be recirculated. The effects of the invention can be sufficiently obtained.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a start control device according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing the structure of a combustion chamber.

FIG. 3 is an explanatory diagram showing valve stroke characteristics of an intake valve and an exhaust valve.

FIG. 4 is a perspective view showing a schematic configuration of a variable valve mechanism with a part thereof cut away.

FIG. 5 is an enlarged view schematically showing a schematic configuration of a turbo motor.

FIG. 6 is a flowchart showing a procedure of fuel injection control when the engine is started.

FIG. 7 is an explanatory diagram showing an example of a target torque map (a), an injection amount map (b) and an injection timing map (c) of the engine.

FIG. 8 is a flowchart showing a procedure of VVT control when the engine is started.

FIG. 9 is an explanatory diagram showing an example of an engine valve timing map.

FIG. 10 is a flowchart showing a control procedure of an EGR valve and an intake throttle valve when starting an engine.

FIG. 11 is an explanatory diagram showing an example of an engine EGR control map (a) and an intake throttle control map (b).

FIG. 12 is a flowchart showing a control procedure of the turbo motor at the time of starting the engine.

FIG. 13 is an explanatory diagram showing an example of a turbo rotation speed control map.

FIG. 14: Accelerator opening degree, fuel supply state, vehicle speed, engine speed, E when decelerating, automatically stopping and restarting the vehicle
GR valve opening, intake throttle opening, intake valve opening / closing timing,
FIG. 4 is a time chart diagram showing changes in intake pressure and turbo rotation speed in association with each other.

[Explanation of symbols]

A Diesel engine start control device 1 engine Two cylinder 16 Intake passage 24 Turbo motor (rotary electric machine) 26 Exhaust passage 27 turbine 30 VGT (turbo supercharger) 34 EGR passage (exhaust gas recirculation passage) 35 EGR valve (open / close valve) 38 Control unit 38c VVT control section (valve mechanism control means) 38d EGR control section (exhaust gas recirculation control means) 38e Turbomotor control unit (rotating electric machine control means) 43 Intake valve 47 VVT (Variable valve mechanism)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F02D 13/02 F02D 13/02 D 3G301 15/00 15/00 E 17/00 17/00 Q 21/08 301 21/08 301D 311 311B 41/06 370 41/06 370 375 375 43/00 301 43/00 301H 301N 301R 301S 301Z F02M 25/07 F02M 25/07 A 570 570E 570P F Term (reference) 3G005 DA02 EA04 EA15 EA15 EA16 EA20 FA35 GA00 GA04 GD07 GE01 GE08 GE09 HA05 HA09 HA12 HA15 JA24 JA40 JB00 JB02 JB17 3G018 AA11 AA12 BA33 CA20 DA82 EA21 EA35 FA07 FA26 FA27 GA32 3G0606 A08 GA10 BA01 GA01 GA01 GA01 GA08 GA08 GA08 GA08 GA08 GA08 GA08 GA08 GA01 GA01 GA08 GA08 GA08 GA08 GA08 GA08 GA08 GA08 GA08 GA08 GA08 GA08 FA07 FA10 FA11 FA12 FA20 FA33 FA38 3G092 AA18 AC03 BA02 BB01 BB10 DA01 DA09 DA14 D B03 DB04 DC03 DC09 DD03 DG05 DG07 EA08 EA12 EC08 EC09 FA18 GA01 HA01Z HA05Z HA06Z HA13X HA16X HB01X HC07Z HE01Z HE03Z HE08Z HF05X HF19Z 3G301 HA02 HA11 HA19 JA26 KA01 LA07 LB11 LC03 LC08 MA25 NC02 PA01Z PA07Z PA11Z PA16Z PB08Z PD15Z PE01Z PE03Z PE08Z

Claims (6)

[Claims] 1. A start control device for a diesel engine including a turbocharger, comprising: a rotating electric machine connected to rotate in conjunction with a turbine of the turbocharger; and the rotating electric machine when the engine is started. A starting control device for a diesel engine, comprising: a rotating electric machine control unit that supercharges intake air by rotating a turbine by operating a motor of the electric machine. 2. The rotating electric machine control means according to claim 1, wherein the supercharging pressure of intake air by the turbocharger is equal to or higher than a first set pressure preset based on a value relating to a predetermined harmful component amount in exhaust gas. A starting control device for a diesel engine, characterized in that the rotating electric machine is controlled as described above. 3. The diesel engine according to claim 2, further comprising fuel control means for starting fuel supply to the engine after the supercharging pressure of intake air becomes equal to or higher than a first set pressure when the engine is started. Engine start control device. 4. The exhaust gas recirculation system according to claim 1, wherein an exhaust gas recirculation passage that connects an intake passage and an exhaust passage of the engine, an opening / closing valve that opens and closes the exhaust gas recirculation passage, and the opening / closing valve that opens when the engine starts. An engine start control device for a diesel engine, comprising: exhaust gas recirculation control means for recirculating at least a part of exhaust gas to an intake passage through a passage. 5. The variable valve mechanism according to claim 4, wherein at least one of the opening / closing timing and the lift amount of the intake valve of the engine can be changed, and the actual compression ratio of the cylinder is relatively low at the time of warm starting of the engine. A starting control device for a diesel engine, comprising: a valve operating mechanism control means for operating the variable valve operating mechanism. 6. The exhaust gas recirculation control means according to claim 4 or 5, wherein the exhaust gas recirculation control means controls the opening degree of the on-off valve so that the amount of exhaust gas recirculated through the exhaust gas recirculation passage becomes equal to or more than a predetermined amount when the engine is warmly started. The rotary electric machine control means controls the rotary electric machine so that the supercharging pressure of the intake air by the turbocharger becomes equal to or lower than the second set pressure at which the predetermined amount of exhaust gas can be recirculated to the intake passage. A starting control device for a diesel engine, which is characterized by being a thing.