JP2018025176A - Vehicle control method and control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize appropriate restriction against fire loss of deposit accumulated in a combustion chamber or accumulation of deposit in the combustion chamber by performing an effective increasing of a temperature within a cylinder of a Diesel engine.SOLUTION: A vehicle control system comprises a Diesel engine E having a fuel injection valve 20; and an air conditioner system including a refrigerant passage 151, a compressor 152, a condenser 153, a condenser fan 154 and an evaporator 157. A control device 60 controls a fuel injection amount to keep a specified engine speed. Additionally, when it is judged that the deposit is accumulated, the control device 60 performs a controlling operation to decrease an output of the condenser so as to increase a refrigerant pressure at an upstream side of the compressor 152 than when it is not judged that the deposit is accumulated and this controlling operation is carried out at the time of maintenance of a vehicle and when the vehicle is not driven.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a control method and a control system for a vehicle including a diesel engine and an air conditioner system.

  Conventionally, as a method of removing deposits accumulated in a cylinder of a diesel engine, for example, there is a method described in Patent Document 1. In the method described in Patent Document 1, the concept of “heat generation rate centroid position” is introduced as an index value representing the combustion state of the engine, and the heat generation rate centroid position at which the sum of the cooling loss and the exhaust loss is minimized. The crank angle is set as the reference crank angle. When deposits accumulate on the top land of the piston more than a certain amount, the heat generation rate gravity center position is advanced from the reference crank angle, thereby raising the temperature of the piston top land and burning the deposit. Yes.

JP 2016-14380 A

  By the way, the deposit may be deposited not only on the top land of the piston as described above, but also in other parts such as around the fuel injection valve. In this case, in order to burn off the deposited deposit, It is necessary to increase the temperature at such a part. In this regard, in the method of burning out the top land deposit of the piston as described above, the piston is exposed to various temperature conditions in the cylinder as the piston moves up and down in the cylinder. It is easy to make an opportunity to raise the temperature necessary for burning. On the other hand, generally, the fuel injection valve is fixed to the upper part of the cylinder. Therefore, in order to burn off the deposit accumulated on the fuel injection valve, the temperature at this specific location must be increased, and the temperature conditions required for deposit burning are more severe.

  For example, in a diesel engine with a low compression ratio, the volume of the combustion chamber at the top dead center is relatively large even if the heat release rate gravity center position is advanced from the reference crank angle as described in Patent Document 1. For this reason, the in-cylinder temperature cannot be increased to a temperature sufficient to burn out deposits deposited on the fuel injection valve.

  The present invention has been made in order to solve the above-described problems of the prior art, and effectively increases the in-cylinder temperature of a diesel engine so that deposits deposited in the combustion chamber are burned out or deposited in the combustion chamber. It is an object of the present invention to provide a vehicle control method and a control system that can appropriately suppress deposition.

In order to achieve the above object, the present invention provides a diesel engine having a fuel injection valve for directly injecting fuel into a combustion chamber, and an air conditioner system driven by the diesel engine, wherein the air conditioner system circulates a refrigerant. And a refrigerant passage provided on the refrigerant passage and driven by a diesel engine so as to compress the refrigerant, and provided on a refrigerant passage downstream of the compressor and compressed by the compressor. An air conditioner system having a condenser that cools the refrigerant, a condenser fan that blows air toward the condenser, and an evaporator that is provided on a refrigerant passage downstream of the condenser and vaporizes the refrigerant from the condenser. A method for controlling a vehicle based on a required torque during vehicle travel The step of controlling the fuel injection amount of the fuel injection valve, the step of determining whether or not deposits are deposited in the combustion chamber, and the deposit is deposited when it is determined that the deposits are deposited. A step of advancing the fuel injection timing of the fuel injection valve and lowering the output of the condenser fan so that the refrigerant pressure on the upstream side of the compressor becomes higher than when not judged. The control for advancing the timing and reducing the output of the condenser fan is performed during maintenance of the vehicle and when the vehicle is not running.
According to the present invention configured as described above, when deposits are accumulated, the fuel injection timing of the fuel injection valve is advanced, and the condenser fan output is controlled to increase the refrigerant pressure, so that the predetermined engine The amount of fuel injection required to maintain the rotational speed is increased. Thereby, a relatively large amount of fuel can be burned to effectively increase the in-cylinder maximum temperature, and deposits accumulated in the combustion chamber (especially the fuel injection valve) can be surely burnt down.
Further, when the control for burning out the deposit as described above is performed during actual vehicle travel, a sense of incongruity (especially noise) may be generated. However, according to the present invention, the control is performed for vehicle maintenance. Since it is performed at the time of non-traveling, occurrence of such a sense of incongruity can be appropriately suppressed.

In another aspect, in order to achieve the above object, the present invention provides an engine having a fuel injection valve for supplying fuel into a combustion chamber, and an air conditioner system driven by the engine, the air conditioner system comprising a refrigerant A refrigerant passage for circulating the refrigerant, a compressor provided on the refrigerant passage and driven by the engine so as to compress the refrigerant, and provided on a refrigerant passage downstream of the compressor and compressed by the compressor. An air conditioner system having a condenser that cools the cooled refrigerant, a condenser fan that blows air toward the condenser, and an evaporator that is provided on a refrigerant passage downstream of the condenser and vaporizes the refrigerant from the condenser. A vehicle control method comprising: fuel injection of a fuel injection valve based on a required torque when the vehicle is running When the request for increasing the engine resistance applied to the engine is issued, the condenser fan is set so that the refrigerant pressure on the upstream side of the compressor becomes higher than when the request for increasing the engine resistance is not issued. And a step of performing a control to reduce the output of.
According to the present invention configured as described above, when a request for increasing the engine resistance is issued (for example, the request is a situation where deposits are likely to accumulate in the combustion chamber, in one example, the combustion gas temperature is relatively low. Controlled by the condenser fan output, the refrigerant pressure is increased to increase the amount of fuel injection required to maintain a predetermined engine speed. Thereby, a relatively large amount of fuel can be burned to effectively increase the in-cylinder maximum temperature, and deposit accumulation in the combustion chamber can be suppressed in advance.

In another aspect, in order to achieve the above object, the present invention provides a diesel engine having a fuel injection valve that directly injects fuel into a combustion chamber, and an air conditioner system driven by the diesel engine, the air conditioner system Is provided on a refrigerant passage for circulating and flowing the refrigerant, a compressor provided on the refrigerant passage, driven by a diesel engine to compress the refrigerant, and a refrigerant passage on the downstream side of the compressor, An air conditioner having a condenser that cools the refrigerant compressed by the compressor, a condenser fan that blows air toward the condenser, and an evaporator that is provided on a refrigerant passage downstream of the condenser and vaporizes the refrigerant from the condenser. And a control method for a vehicle comprising: A step of controlling the fuel injection amount of the fuel injection valve based on the flow rate, a step of determining whether or not deposits are deposited in the combustion chamber, and deposits when it is determined that deposits are deposited. Performing a first control for advancing the fuel injection timing of the fuel injection valve and lowering the output of the condenser fan so that the refrigerant pressure on the upstream side of the compressor becomes higher than when it is not determined that When the engine resistance increase request given to the diesel engine is issued, the fuel injection timing of the fuel injection valve is advanced and the refrigerant pressure on the upstream side of the compressor is compared with the case where the engine resistance increase request is not issued. And performing a second control for reducing the output of the condenser fan so that the power becomes high. The first control is performed during maintenance of the vehicle and when the vehicle is not running. Is, the second control is performed during running of the vehicle, amount of advancing the fuel injection timing in the second control is smaller than an amount to advance the fuel injection timing in the first control, characterized in that.
According to the present invention configured as described above, the in-cylinder maximum temperature can be effectively increased by controlling the condenser fan output and increasing the refrigerant pressure to increase the fuel injection amount. As a result, the deposit accumulated in the combustion chamber can be appropriately burned down by the first control when the vehicle is being maintained and not running, and the deposit in the combustion chamber can be properly burned by the second control when the vehicle is running. Accumulation can be suppressed in advance.
Further, according to the present invention, the advance amount of the fuel injection timing applied to the second control is made smaller than the advance amount of the fuel injection timing applied to the first control, so that the second control is performed when the vehicle is traveling. Therefore, it is possible to appropriately suppress the deterioration of combustion stability and the occurrence of discomfort (noise, etc.) due to the advance of the fuel injection timing.

In the present invention, it is preferable to further include a step of estimating the combustion gas temperature in the combustion chamber and reducing the degree of decreasing the output of the condenser fan as the difference between the combustion gas temperature and the predetermined temperature is smaller.
According to the present invention configured as described above, it is possible to minimize an increase in engine resistance due to an increase in refrigerant pressure and to suppress fuel consumption deterioration caused by the control as much as possible.

In the present invention, preferably, the method further includes a step of increasing the degree of decreasing the output of the condenser fan as the outside air temperature is lower.
According to the present invention configured as described above, the lower the outside air temperature, the greater the degree to which the output of the condenser fan is reduced. In other words, the higher the outside air temperature is, the smaller the degree to which the output of the condenser fan is reduced. . As a result, the refrigerant pressure on the upstream side of the compressor can be appropriately increased regardless of the outside air temperature, and the fuel injection amount can be appropriately increased as described above.

In the present invention, the control for advancing the fuel injection timing and reducing the output of the condenser fan is preferably performed in a state where the air conditioner system is set to heating.
According to the present invention configured as described above, it is possible to suppress the stoppage of the operation of the air conditioner system due to the freezing of the air after passing through the evaporator, which may occur by performing the above control in a state where the air conditioner system is set to cooling in midwinter or the like. be able to.

In another aspect, in order to achieve the above object, the present invention provides a diesel engine having a fuel injection valve that directly injects fuel into a combustion chamber, and an air conditioner system driven by the diesel engine, the air conditioner system Is provided on a refrigerant passage for circulating and flowing the refrigerant, a compressor provided on the refrigerant passage, driven by a diesel engine to compress the refrigerant, and a refrigerant passage on the downstream side of the compressor, An air conditioner having a condenser that cools the refrigerant compressed by the compressor, a condenser fan that blows air toward the condenser, and an evaporator that is provided on a refrigerant passage downstream of the condenser and vaporizes the refrigerant from the condenser. System and control device for controlling fuel injection valve and air conditioner system The control system controls the fuel injection amount of the fuel injection valve based on the required torque when the vehicle is running, determines whether or not deposit is accumulated in the combustion chamber, and the deposit is When it is determined that the deposit is accumulated, the condenser fan is advanced so that the fuel injection timing of the fuel injection valve is advanced and the refrigerant pressure on the upstream side of the compressor is higher than when the deposit is not determined to be accumulated. The control is performed to reduce the output of the vehicle, and this control is performed during maintenance of the vehicle and when the vehicle is not running.
According to the present invention thus configured, by increasing the refrigerant pressure by controlling the condenser fan and increasing the fuel injection amount, a relatively large amount of fuel is burned and the maximum in-cylinder temperature is effectively increased. Thus, deposits accumulated in the combustion chamber (particularly the fuel injection valve) can be reliably burned out. In addition, according to the present invention, since the above control is performed when the vehicle is being maintained and when the vehicle is not traveling, it is possible to appropriately suppress the occurrence of a sense of incongruity caused by the control.

In another aspect, in order to achieve the above object, the present invention provides an engine having a fuel injection valve for supplying fuel into a combustion chamber, and an air conditioner system driven by the engine, the air conditioner system comprising a refrigerant A refrigerant passage for circulating the refrigerant, a compressor provided on the refrigerant passage and driven by the engine so as to compress the refrigerant, and provided on a refrigerant passage downstream of the compressor and compressed by the compressor. An air conditioner system comprising: a condenser for cooling the generated refrigerant; a condenser fan for blowing air toward the condenser; and an evaporator provided on a refrigerant passage downstream of the condenser and vaporizing the refrigerant from the condenser; And a control device for controlling the injection valve and the air conditioner system. The control device controls the fuel injection amount of the fuel injection valve based on the required torque when the vehicle travels, and when the request for increasing the engine resistance applied to the engine is issued, the request for increasing the engine resistance is issued. It is configured to perform control to reduce the output of the condenser fan so that the refrigerant pressure on the upstream side of the compressor becomes higher than when there is no compressor.
According to the present invention thus configured, by increasing the refrigerant pressure by controlling the condenser fan and increasing the fuel injection amount, a relatively large amount of fuel is burned and the maximum in-cylinder temperature is effectively increased. It is possible to suppress deposit accumulation in the combustion chamber.

In another aspect, in order to achieve the above object, the present invention provides a diesel engine having a fuel injection valve that directly injects fuel into a combustion chamber, and an air conditioner system driven by the diesel engine, the air conditioner system Is provided on a refrigerant passage for circulating and flowing the refrigerant, a compressor provided on the refrigerant passage, driven by a diesel engine to compress the refrigerant, and a refrigerant passage on the downstream side of the compressor, An air conditioner having a condenser that cools the refrigerant compressed by the compressor, a condenser fan that blows air toward the condenser, and an evaporator that is provided on a refrigerant passage downstream of the condenser and vaporizes the refrigerant from the condenser. System and control device for controlling fuel injection valve and air conditioner system The control system controls the fuel injection amount of the fuel injection valve based on the required torque when the vehicle is running, determines whether or not deposit is accumulated in the combustion chamber, and the deposit is When it is determined that the deposit is accumulated, the condenser fan is advanced so that the fuel injection timing of the fuel injection valve is advanced and the refrigerant pressure on the upstream side of the compressor is higher than when the deposit is not determined to be accumulated. When the request for increasing the engine resistance applied to the diesel engine is issued, the fuel injection timing of the fuel injection valve is higher than when the request for increasing the engine resistance is not issued. When the vehicle is being serviced, the second control is performed to reduce the output of the condenser fan so that the refrigerant pressure on the upstream side of the compressor is increased. The first control is performed when the vehicle is not traveling, the second control is performed when the vehicle is traveling, and the amount by which the fuel injection timing is advanced in the second control is made smaller than the amount by which the fuel injection timing is advanced in the first control. It is characterized by being comprised.
According to the present invention configured as described above, the deposit accumulated in the combustion chamber can be appropriately burned off by the first control when the vehicle is being maintained and not running, and when the vehicle is running, By control, deposit accumulation in the combustion chamber can be suppressed in advance. Further, according to the present invention, the advance amount of the fuel injection timing applied to the second control is made smaller than the advance amount of the fuel injection timing applied to the first control, so that the second control is performed when the vehicle is traveling. Therefore, it is possible to appropriately suppress the deterioration of combustion stability and the occurrence of discomfort (noise, etc.) due to the advance of the fuel injection timing.

In the present invention, preferably, the control device is configured to estimate the combustion gas temperature in the combustion chamber, and to reduce the degree of decreasing the output of the condenser fan as the difference between the combustion gas temperature and the predetermined temperature is smaller. Yes.
According to the present invention configured as described above, it is possible to minimize an increase in engine resistance due to an increase in refrigerant pressure and to suppress fuel consumption deterioration caused by the control as much as possible.

In the present invention, preferably, the control device is configured to increase the degree of reduction of the output of the condenser fan as the outside air temperature is lower.
According to the present invention configured as described above, the refrigerant pressure on the upstream side of the compressor can be appropriately increased regardless of the outside air temperature, and the fuel injection amount can be appropriately increased as described above.

In the present invention, preferably, the control device is configured to perform the control to advance the fuel injection timing and reduce the output of the condenser fan while the air conditioner system is set to heating.
According to the present invention configured as described above, it is possible to suppress the stoppage of the operation of the air conditioner system due to the freezing of the air after passing through the evaporator, which may occur by performing the above control in a state where the air conditioner system is set to cooling in midwinter or the like. be able to.

  According to the control method and control system for a vehicle according to the present invention, the in-cylinder temperature of the diesel engine is effectively increased, and the deposit accumulated in the combustion chamber is appropriately burned out or the deposit accumulation in the combustion chamber is appropriately suppressed. can do.

1 is a schematic configuration diagram of an engine system according to an embodiment of the present invention. It is a block diagram which shows the electric constitution of the control apparatus by embodiment of this invention. It is an expanded sectional view of the fuel injection valve by this embodiment of the present invention. It is a schematic structure figure showing an air-conditioner system by an embodiment of the present invention. It is explanatory drawing about the relationship between the output of an air-conditioner condenser fan, the refrigerant | coolant pressure of the upstream of a compressor, and an air-conditioner load. It is a time chart at the time of controlling an air-conditioner condenser fan at the time of deposit burning control in the embodiment of the present invention. It is a flowchart which shows the main control by embodiment of this invention. It is a flowchart which shows the deposit accumulation determination process by embodiment of this invention. It is a flowchart which shows the deposit burnout control by embodiment of this invention. It is a time chart at the time of controlling an air-conditioner condenser fan at the time of deposit burning control in the modification of embodiment of this invention.

  Hereinafter, a vehicle control method and a control system according to embodiments of the present invention will be described with reference to the accompanying drawings.

<System configuration>
First, a system to which a vehicle control method and a control system according to an embodiment of the present invention are applied will be described with reference to FIGS. 1 and 2. Specifically, FIG. 1 is a schematic configuration diagram of an engine system according to an embodiment of the present invention, and FIG. 2 is a block diagram showing an electrical configuration of a control device according to the embodiment of the present invention.

  As shown in FIG. 1, the engine system 200 mainly includes an engine E as a diesel engine, an intake system IN that supplies intake air to the engine E, a fuel supply system FS that supplies fuel to the engine E, It has an exhaust system EX that exhausts exhaust gas of the engine E, and sensors 101 to 122 that detect various states relating to the engine system 200.

  First, the intake system IN has an intake passage 1 through which intake air passes, and an air cleaner 3 that purifies air introduced from the outside in order from the upstream side, and intake air that passes through the intake passage 1. The compressor 5a of the turbocharger 5 that compresses and raises the intake pressure, the intake shutter valve 7 that adjusts the flow rate of the intake air that passes through, and the water-cooled intercooler that cools the intake air using the coolant that has passed through 8, a water pump 9 that controls the flow rate of the cooling water flowing through the intercooler 8, and a cooling water passage 10 that connects the intercooler 8 and the water pump 9 and circulates the cooling water therebetween. And a surge tank 12 for temporarily storing the intake air supplied to the engine E.

  In the intake system IN, an air flow sensor 101 for detecting the intake air amount and an intake air temperature sensor 102 for detecting the intake air temperature are provided on the intake passage 1 immediately downstream of the air cleaner 3. 5 is provided with a turbo rotational speed sensor 103 for detecting the rotational speed (turbo rotational speed) of the compressor 5a, and the intake shutter valve 7 is provided with an intake shutter for detecting the opening degree of the intake shutter valve 7. A valve position sensor 105 is provided, and an intake air temperature sensor 106 for detecting the intake air temperature and an intake air pressure sensor 107 for detecting the intake air pressure are provided on the intake passage 1 immediately downstream of the intercooler 8. Is provided with an intake manifold temperature sensor 108. Various sensors 101 to 103 and 105 to 108 provided in the intake system IN output detection signals S101 to S103 and S105 to S108 corresponding to the detected parameters, respectively, to the control device 60 (see FIG. 2).

Next, the engine E includes an intake valve 15 that introduces intake air supplied from the intake passage 1 (specifically, an intake manifold) into the combustion chamber 17, a fuel injection valve 20 that directly injects fuel into the combustion chamber 17, The glow plug 21 as an auxiliary heat source for ensuring ignitability at the time of cold start or the like, the piston 23 reciprocating by combustion of the air-fuel mixture in the combustion chamber 17, and the reciprocating motion of the piston 23 are rotated. A crankshaft 25 and an exhaust valve 27 for discharging exhaust gas generated by combustion of the air-fuel mixture in the combustion chamber 17 to the exhaust passage 41 are provided. Further, the engine E is provided with an alternator 26 that generates electric power using the output of the engine E. The electric power generated by the alternator 26 is supplied to a battery (not shown), and this electric power is supplied to various auxiliary machines (for example, the rear differential 141 and the headlight 142) in the vehicle to drive the various auxiliary machines.
The fuel injection valve 20 includes a plurality of injection holes on the injection surface, that is, is configured as a multi-hole type, and injects fuel from these injection holes in a plurality of directions. In addition, the glow plug 21 is disposed so that the heat generating portion provided in the combustion chamber 17 is positioned between the plurality of sprays from the plurality of nozzle holes of the fuel injection valve 20. That is, the heat generating part of the glow plug is disposed at a position where it does not directly contact the fuel spray. By doing so, problems (such as failure of the glow plug 21) due to the direct application of fuel to the heat generating portion of the glow plug 21 are prevented. Basically, when the glow plug 21 is energized, the heat generating portion generates heat, and combustion starts in the cylinder using this heat as a heat source. And the in-cylinder pressure rises by this combustion, and the ignitability in the whole cylinder is ensured.

  Further, the engine E includes a cooling water temperature sensor 109 that detects the temperature (water temperature) of cooling water that cools the engine E and the like, a crank angle sensor 110 that detects the crank angle of the crankshaft 25, and hydraulic pressure and / or oil. An oil pressure / oil temperature sensor 111 for detecting the temperature and an optical oil level sensor 112 for detecting the oil level are provided. These various sensors 109 to 112 provided in the engine E output detection signals S109 to S112 corresponding to the detected parameters to the control device 60, respectively.

Next, the fuel supply system FS includes a fuel tank 30 for storing fuel, and a fuel supply passage 38 for supplying fuel from the fuel tank 30 to the fuel injection valve 20. In the fuel supply passage 38, a low-pressure fuel pump 31, a high-pressure fuel pump 33, and a common rail 35 are provided in order from the upstream side. The low pressure fuel pump 31 is provided with a fuel warmer 32, the high pressure fuel pump 33 is provided with a fuel pressure regulator 34, and the common rail 35 is provided with a common rail pressure reducing valve 36.
In the fuel supply system FS, the high-pressure fuel pump 33 is provided with a fuel temperature sensor 114 that detects the fuel temperature, and the common rail 35 is provided with a fuel pressure sensor 115 that detects the fuel pressure. These various sensors 114 and 115 provided in the fuel supply system FS output detection signals S114 and S115 corresponding to the detected parameters to the control device 60, respectively.

  Next, the exhaust system EX has an exhaust passage 41 through which the exhaust gas passes. The exhaust passage 41 is rotated by the exhaust gas passing through the exhaust passage 41 in order from the upstream side. A turbine 5b of the turbocharger 5 that drives the compressor 5a, a diesel oxidation catalyst (DOC) 45 having a function of purifying exhaust gas, a diesel particulate filter (DPF) 46, and a passage And an exhaust shutter valve 49 for adjusting the exhaust flow rate. The DOC 45 is a catalyst that oxidizes hydrocarbon (HC), carbon monoxide (CO), and the like using oxygen in the exhaust gas to change it into water and carbon dioxide, and the DPF 46 is a particulate substance ( It is a filter that collects PM (Particulate Matter).

In the exhaust system EX, an exhaust pressure sensor 116 for detecting the exhaust pressure and an exhaust temperature sensor 117 for detecting the exhaust temperature are provided on the exhaust passage 41 on the upstream side of the turbine 5b of the turbocharger 5. Exhaust temperature sensors 118 and 119 for detecting the exhaust temperature are respectively provided immediately upstream of the DOC 45 and between the DOC 45 and the DPF 46. On the exhaust passage 41 near the DPF 46, upstream and downstream of the DPF 46 are provided. A DPF differential pressure sensor 120 for detecting a difference in exhaust pressure with respect to the exhaust side (hereinafter referred to as “DPF differential pressure”) is provided, and a linear for detecting oxygen concentration is provided on the exhaust passage 41 immediately downstream of the DPF 46. An O ₂ sensor 121 and an exhaust temperature sensor 122 for detecting the exhaust temperature are provided. These various sensors 116 to 122 provided in the exhaust system EX output detection signals S116 to S122 corresponding to the detected parameters to the control device 60, respectively.

  The turbocharger 5 is configured in a small size so that the turbocharging can be performed efficiently even at low speed rotation with low exhaust energy. The turbocharger 5 is provided with a plurality of movable flaps 5c so as to surround the entire circumference of the turbine 5b, and these flaps 5c change the flow cross-sectional area (nozzle cross-sectional area) of the exhaust gas to the turbine 5b. This is configured as a variable geometry turbocharger (VGT). For example, the flap 5c is rotated by an actuator with the magnitude of the negative pressure acting on the diaphragm adjusted by an electromagnetic valve. Further, a VGT opening sensor 104 is provided for detecting the opening of the flap 5c (which is the flap opening, hereinafter referred to as “VGT opening” as appropriate) depending on the position of the actuator. The VGT opening sensor 104 outputs a detection signal S104 corresponding to the detected VGT opening to the control device 60.

  Further, the engine system 200 includes a high pressure EGR device 43 and a low pressure EGR device 48. The high-pressure EGR device 43 connects the exhaust passage 41 upstream of the turbine 5b of the turbocharger 5 and the intake passage 1 downstream of the compressor 5b of the turbocharger 5 (specifically, downstream of the intercooler 8). And a high pressure EGR valve 43b that adjusts the flow rate of exhaust gas that passes through the high pressure EGR passage 43a. The low pressure EGR device 48 includes an exhaust passage 41 on the downstream side of the turbine 5b of the turbocharger 5 (specifically, on the downstream side of the DPF 46 and the upstream side of the exhaust shutter valve 49) and the upstream side of the compressor 5b of the turbocharger 5. A low pressure EGR passage 48a that connects the intake passage 1 of the engine, a low pressure EGR cooler 48b that cools the exhaust gas that passes through the low pressure EGR passage 48a, and a low pressure EGR valve 48c that adjusts the flow rate of the exhaust gas that passes through the low pressure EGR passage 48a. And a low pressure EGR filter 48d.

  Next, referring to FIG. 2, in addition to the detection signals S101 to S122 of the various sensors 101 to 122 shown in FIG. 1, the control device 60 detects an outside air temperature sensor 98 that detects the outside air temperature, and detects the atmospheric pressure. Detection signals S98 to S100 output from the pressure sensor 99 and the accelerator opening sensor 100 that detects the opening (accelerator opening) of the accelerator pedal 95 are input. Further, the control device 60 switches on / off the rear differential 141 (formally “rear defogger”, but the term “rear def” is generally used as an abbreviation in this specification). A rear differential switch 94, a headlight switch 95 for switching on / off of the headlight 142, an air conditioner switch 96 for switching on / off of the air conditioner system, and an air volume changeover switch 97 for switching the air volume of the air conditioner system. The signals S94 to S97 output by are input.

  The control device 60 includes at least a PCM (Power-train Control Module), and controls various components in the vehicle based on the signals S94 to S122 described above. Specifically, the control device 60 controls a control signal for an actuator (not shown) that drives the flap 5c in order to control the opening (VGT opening) of the flap 5c in the turbine 5b of the turbocharger 5. S130 is output. Further, the control device 60 outputs a control signal S131 to an actuator (not shown) that drives the intake shutter valve 7 in order to control the opening degree of the intake shutter valve 7. Further, the control device 60 outputs a control signal S132 to the glow plug 21 in order to control the voltage and / or current applied to the glow plug 21. Further, the control device 60 outputs a control signal S133 to the fuel injection valve 20 in order to control the fuel injection amount and fuel injection timing of the engine E. In the present embodiment, the control device 60 controls the fuel injection valve 20 so as to perform at least two pre-injections before the main injection (main injection). The pre-injection is a fuel injection for creating a fire type in advance in the combustion chamber 17 of the engine E in order to reduce NOx and improve combustion noise. Main injection is fuel injection for generating engine torque to be output, and fuel injection for actively controlling engine torque.

  In addition, the control device 60 outputs control signals S134, S135, S136, and S137 to control the alternator 26, the fuel warmer 32, the fuel pressure regulator 34, and the common rail pressure reducing valve 36, respectively. Further, the control device 60 outputs a control signal S138 to an actuator (not shown) that drives the high pressure EGR valve 43b in order to control the opening degree of the high pressure EGR valve 43b. Further, the control device 60 outputs a control signal S139 to an actuator (not shown) that drives the low pressure EGR valve 48c in order to control the opening degree of the low pressure EGR valve 48c. Further, the control device 60 outputs a control signal S140 to an actuator (not shown) that drives the exhaust shutter valve 49 in order to control the opening degree of the exhaust shutter valve 49.

  In addition, the control device 60 supplies control signals S141 and S142 to each of the rear differential 141 and the headlight 142 as auxiliary machines in the vehicle. Further, the control device 60 outputs a control signal S154 to the air conditioner condenser fan 154 in order to control the operation of the air conditioner condenser fan 154 for cooling the refrigerant passing through the condenser of the air conditioner system. Further, the control device 60 outputs a control signal S159 to the air conditioner compressor clutch 159 so as to switch connection / disconnection of the air conditioner compressor clutch 159 provided in the compressor for compressing the refrigerant of the air conditioner system.

  The control device 60 includes a CPU, various programs that are interpreted and executed on the CPU (including basic control programs such as an OS and application programs that are activated on the OS to realize specific functions), programs, and various types of programs. It is constituted by a computer having an internal memory such as a ROM or RAM for storing data.

<Deposit deposit>
In the present embodiment, the control device 60 performs deposit burnout control in which when the deposit is accumulated in the combustion chamber 17 (particularly, the fuel injection valve 20), the temperature of the combustion chamber 17 is raised to burn out the deposited deposit. Hereinafter, the deposit burnout control for the purpose of burning the deposit accumulated on the fuel injection valve 20 will be described.

FIG. 3 is an enlarged cross-sectional view of the fuel injection valve 20 according to the present embodiment. As shown in FIG. 3, the fuel injection valve 20 includes a substantially cylindrical main body 20a, a needle valve 20b that can move in the axial direction inside the main body 20a, and a circumferentially equal interval on the tip side of the main body 20a. And a plurality of nozzle holes 20c formed on the surface. On the outer surface of the main body 20a, a substantially cylindrical recess 20d having a diameter larger than that of the nozzle hole 20c is formed at a position corresponding to the nozzle hole 20c.
The fuel injection valve 20 is arranged so that the tip end side thereof protrudes into the combustion chamber 17 of the engine E, so that the injection hole 20 c opens into the combustion chamber 17.

In the fuel injection valve 20 having such a structure, when the needle valve 20b moves in the axial direction, a gap is formed between the main body 20a and the needle valve 20b, and fuel passing through the gap burns from the nozzle hole 20c. It is injected into the chamber 17.
Here, a recess 20d is formed around the injection hole 20c, and a small amount of the injected fuel adheres in the recess 20d. The fuel adhering in this way does not easily mix with the air in the combustion chamber 17 and does not burn well, and remains in the recess 20d as a deposit.

When the operation is performed at a high load, the temperature in the combustion chamber 17 becomes high, and most of the generated deposit is burned out. However, in operation with a low load, the temperature in the combustion chamber 17 is not so high. For this reason, when the operation at a low load is repeated, the deposit does not burn out and tends to accumulate in the recess 20d. In particular, since the recess 20d of the fuel injection valve 20 is recessed from the outer surface of the main body 20a of the fuel injection valve 20, it is far from the combustion gas, and the surface area of the recess 20d is relatively large. It is easy to become. Moreover, since the nozzle hole 20c is cooled by the heat of vaporization of the fuel when the fuel is injected from the nozzle hole 20c, the space in the recess 20d is also likely to become low temperature. For this reason, the deposit in the recess 20d is easily deposited without being burned out.
If deposits accumulate in the recess 20d of the fuel injection valve 20 in this way, good fuel injection from the injection hole 20c is hindered, and homogeneous combustion in the combustion chamber 17 is not performed, causing problems such as deterioration in fuel consumption. Occur.

In the present embodiment, focusing on the deposit accumulated in the recess 20d of the fuel injection valve 20, the control device determines that the deposit has accumulated in the recess 20d for the purpose of burning the deposit accumulated in this portion. 60 performs deposit burning control for burning the deposit.
In order to burn off the deposit accumulated in the recess 20d, the surface temperature of the fuel injection valve 20 requires a temperature of, for example, 250 ° C. or higher. As described above, the concave portion 20d of the fuel injection valve 20 is a portion in which the temperature does not easily rise in the combustion chamber 17, and therefore, in order to make the surface temperature of the fuel injection valve 20 higher than such a temperature, The maximum temperature (in other words, the maximum temperature of the combustion gas, which corresponds to the in-cylinder temperature at the compression top dead center) needs to be much higher than usual, for example, 1500 K (or 1227 ° C.) or higher. Therefore, in this embodiment, the required in-cylinder temperature for deposit burnout control is set to 1500 K (or 1227 ° C.) or higher.

<Advance control of fuel injection timing>
In order to burn out the deposit in the recess 20d of the fuel injection valve 20, in the present embodiment, the control device 60 performs the fuel injection timing rather than during normal operation (when the deposit burnout control is not performed. The same applies hereinafter). By advancing (fuel injection start timing), the combustion gravity center position is advanced, the in-cylinder maximum temperature is increased, and the surface temperature of the fuel injection valve 20 necessary for deposit burnout is increased to a predetermined value or more. Specifically, the control device 60 determines the first crank angle of the engine cycle at the fuel injection timing of the fuel injection valve 20 when the vehicle is traveling at a certain rotation speed and required torque of the engine E during normal operation. When the crank angle is used, during the deposit burnout control, the second crank angle (at least in compression) is advanced from the first crank angle at the same rotational speed and required torque as in the normal operation. The fuel injection is started at the crank angle before the dead center).

  In the present embodiment, fuel injection is performed in three stages (two pre-injections and then main injection), and the fuel injection that starts at the second crank angle is a main injection that mainly contributes to the start of combustion. Point to. Therefore, the second crank angle is set as a crank angle at a position where the main injection is started and advanced by a predetermined advance amount ΔT (defined by the rotation angle of the crankshaft 25) from the compression top dead center. Is done.

(1) Setting of minimum required advance amount The minimum value ΔT _min of the advance amount ΔT with respect to the compression top dead center of the second crank angle, that is, the minimum required advance amount is set as follows.

  Basically, the higher the fuel injection timing of the main injection is earlier than the compression top dead center (TDC), the higher the maximum temperature of the combustion gas. The advance amount ΔT is set to a fuel injection timing that can realize a combustion start timing at which the maximum temperature of the combustion gas is equal to or higher than the required in-cylinder temperature (1500 K (or 1227 ° C. in this embodiment)).

  Further, the maximum temperature of the combustion gas changes according to the geometric compression ratio of the engine E. When the geometric compression ratio of the engine E becomes low, the maximum temperature of the combustion gas becomes low. Here, in this embodiment, a low compression ratio diesel engine having a geometric compression ratio of about 14 is employed. For this reason, even if fuel is injected in the compression stroke and combustion is started, the degree of compression of the gas up to the compression top dead center is reduced as compared with an engine with a high compression ratio. Temperature does not rise easily. Therefore, in order to achieve the required in-cylinder temperature, it is necessary to increase the advance amount ΔT and set the fuel injection timing earlier than when the geometric compression ratio is relatively high. Thus, by relatively advancing the fuel injection timing, the temperature increase period due to compression after combustion becomes longer, and the maximum temperature of the combustion gas in the cylinder increases. Therefore, from this viewpoint, the advance amount ΔT is set to be larger as the geometric compression ratio is lower.

  As described above, the advance amount ΔT changes in accordance with the geometric compression ratio of the engine E. From the above viewpoint, the present inventor has a relationship between the geometric compression ratio and the advance amount ΔT. And the following formula was found.

ΔT ≧ a ₁ × CR + b ₁

Here, ΔT is the advance amount from the compression top dead center, and CR is the geometric compression ratio of the engine E. Further, a ₁ and b ₁ are constants, and a ₁ <0.

In the above functions, a ₁ and b ₁ are constants determined according to the operating condition of the engine E. In this embodiment, the operating conditions at the time of deposit burnout control are as follows: engine E rotation speed 1750 rpm, supercharging pressure 130 kPa, engine water temperature 82 ° C., fuel injection pressure 70 MPa, intake air temperature 25 ° C., load (average The effective pressure is set to be 300 kPa. Under this condition, a ₁ and b ₁ are a ₁ = −3.56 and b ₁ = 88.7, respectively. It should be noted that the specific values of a ₁ and b ₁ are the engine values in the case where control is performed such as reduction of the EGR gas amount described later, increase in supercharging pressure, increase in engine resistance due to energization of the glow plug 21, etc. It is a numerical value calculated under the condition of E.
In the present embodiment, using such a function, the range of the advance amount ΔT is obtained according to the geometric compression ratio, and the minimum value ΔT _min of the advance amount ΔT is determined.

(2) Setting of Maximum Required Advance Amount The maximum value ΔT _max of the advance amount ΔT with respect to the compression top dead center of the second crank angle, that is, the maximum required advance amount is set as follows.

  Basically, the earlier the fuel injection timing of main injection is from the compression top dead center (TDC), the lower the temperature of the injected fuel. The advance amount ΔT is set at a fuel injection timing such that the temperature of the injected fuel reaches a predetermined ignition possible temperature.

Further, the temperature of the injected fuel changes according to the geometric compression ratio of the engine E, and when the geometric compression ratio of the engine E becomes low, the temperature of the injected fuel becomes low. Here, in this embodiment, a low compression ratio diesel engine having a geometric compression ratio of about 14 is employed. For this reason, if the advance amount ΔT is too large, when the fuel is injected, the fuel does not reach the ignition temperature and combustion is not started at a desired timing, or the combustion becomes incomplete, and the maximum in-cylinder temperature is reached. May become insufficient. Therefore, in this embodiment, it is necessary to set the advance angle amount ΔT to be smaller and the fuel temperature at the fuel injection timing to be higher than when the geometric compression ratio is relatively high.
Therefore, from this point of view, the advance amount ΔT is set smaller as the geometric compression ratio is lower.

  As described above, the advance amount ΔT changes in accordance with the geometric compression ratio of the engine E. From the above viewpoint, the present inventor has a relationship between the geometric compression ratio and the advance amount ΔT. And the following formula was found.

ΔT ≦ a ₂ × CR + b ₂

Here, ΔT is the advance amount from the compression top dead center, and CR is the geometric compression ratio of the engine E. A ₂ and b ₂ are constants, and a ₂ > 0.

Among the above functions, a ₂ and b ₂ are constants determined according to the operating condition of the engine E. In the present embodiment, as described above, the operating conditions at the time of deposit burnout control are as follows: engine E rotation speed is 1750 rpm, supercharging pressure is 130 kPa, engine water temperature is 82 ° C., fuel injection pressure is 70 MPa, and intake air temperature is 25 The temperature (degree C) and the load (average effective pressure) are set to 300 kPa. Under this condition, a ₂ and b ₂ are a ₂ = 4.2 and b ₂ = −47, respectively. It should be noted that the specific values of a ₂ and b ₂ are engine E values when control is performed such as reduction of the EGR amount described later, increase of supercharging pressure, increase of engine resistance due to energization of the glow plug 21, and the like. It is a numerical value calculated under the conditions of
In the present embodiment, using such a function, the range of the advance amount ΔT is obtained according to the geometric compression ratio, and the maximum value ΔT _max of the advance amount ΔT is determined.

With the setting method as described above, the minimum value ΔT _min and the maximum value ΔT _max of the advance amount ΔT are determined, and the advance amount ΔT is determined within the range of ΔT _min ≦ ΔT ≦ ΔT _max .
In this embodiment, ΔT is set to 40 °, and therefore the second crank angle is 40 ° before compression top dead center. In the present embodiment, the control device 60 performs two pre-injections by the fuel injection valve 20 at 56 ° before compression top dead center and 48 ° before compression top dead center, and performs main injection at 40 ° before compression top dead center. At the second crank angle, combustion is started at a position 25 ° before compression top dead center.

<Control of EGR gas amount during deposit burnout control>
In the present embodiment, when the fuel injection timing is advanced as described above, the control device 60 performs control to reduce the EGR gas amount from that during normal operation, thereby increasing the in-cylinder oxygen concentration, Increase the maximum temperature effectively. In particular, in the present embodiment, the control device 60 controls both the high-pressure EGR valve 43b of the high-pressure EGR device 43 and the low-pressure EGR valve 48c of the low-pressure EGR device 48 to be fully closed during the deposit burnout control, and enters the intake system IN. The introduction of EGR gas is cut off.

  When the amount of EGR gas is reduced as described above, the intake pressure becomes relatively high, the resistance is increased in the intake stroke in which the piston 23 is lowered, and the pump loss is increased. Therefore, the fuel injection amount required to maintain the desired engine speed increases (the diesel engine does not adjust the intake air amount with the throttle valve unlike the gasoline engine, so the desired engine speed is maintained. In order to adjust the fuel injection amount). As a result, by burning a relatively large amount of fuel, the in-cylinder gas temperature rises, and the deposit accumulated on the fuel injection valve 20 can be effectively burned out.

<Glow plug control during deposit burnout control>
In the present embodiment, the control device 60 increases the energization amount of the glow plug 21 (meaning an energization current or energization voltage; the same shall apply hereinafter) during the deposit burnout control as compared to during normal operation. Specifically, the control device 60 determines the energization amount to the glow plug 21 at the time of deposit burnout control when the energization amount to the glow plug 21 at a certain rotation speed and required torque during normal operation is set as the first energization amount. The second energization amount is controlled to be higher than the first energization amount.

  As described above, if the advance amount ΔT with respect to the compression top dead center of the second crank angle is excessively increased, when the fuel is injected, the fuel does not reach the ignition temperature and combustion is not started at a desired timing. Or combustion may become incomplete and there exists a possibility that the in-cylinder maximum temperature may become inadequate. Therefore, it is preferable to improve the ignition environment by increasing the energization amount of the glow plug 21 so that the in-cylinder temperature reaches the fuel ignition temperature at a desired time.

  Therefore, in the present embodiment, the higher in-cylinder maximum temperature in the combustion chamber 17 is realized by increasing the energization amount to the glow plug 21 to increase the in-cylinder temperature and advance the combustion start timing of the fuel. To do. Specifically, in the present embodiment, during normal operation, the glow plug 21 is energized only at the time of warm-up at the start of operation of the engine E. Therefore, the rotational speed and required torque of the engine E during deposit burnout control At the same rotation speed and required torque, the glow plug 21 is not energized during normal operation. Therefore, basically, the first energization amount of the glow plug 21 applied during normal operation is zero. On the other hand, during the deposit burnout control, the second energization amount is controlled so that the glow plug 21 reaches a target temperature (for example, 1200 ° C.).

  Since the glow plug 21 uses the electric power generated by the alternator 26, if the energization amount of the glow plug 21 is increased during the deposit burnout control as described above, the required power generation amount at the alternator 26 is increased and applied to the engine E. Resistance (load) to be increased. As a result, the amount of fuel injection required to maintain the desired engine speed increases. As a result, by burning a relatively large amount of fuel, the in-cylinder gas temperature rises, and the deposit accumulated on the fuel injection valve 20 can be effectively burned out.

<Control of supercharging pressure during deposit burnout control>
In the present embodiment, the control device 60 performs control to increase the supercharging pressure by the turbocharger 5 more than during normal operation during deposit burnout control. In this way, the in-cylinder pressure is increased to improve the ignition environment in the combustion chamber 17, and the deterioration of fuel ignitability and incomplete combustion due to the advance of the fuel injection timing as described above are suppressed. To do. Further, when the boost pressure is increased in this way, the resistance applied to the engine E, particularly the resistance applied to the piston 23 (hereinafter referred to as “piston resistance” as appropriate) increases, so that the desired engine rotation speed is increased. The amount of fuel injection required to maintain the number will increase. As a result, by burning a relatively large amount of fuel, the in-cylinder gas temperature rises, and the deposit accumulated on the fuel injection valve 20 can be effectively burned out.

  The controller 60 sets, as a target value (target engine speed), an engine speed that is higher than the idling speed and at which a certain level of supercharging pressure is ensured during deposit burnout control. . More specifically, the control device 60 sets a low engine speed as a target engine speed so as to appropriately maintain a relatively slow piston speed in order to secure the time required for fuel injection and fuel diffusion, and deposit burnout. Execute control. For example, the control device 60 sets the target rotational speed to 1750 rpm.

<Control of auxiliary machine drive resistance during deposit burnout control>
In the present embodiment, the control device 60 performs control to increase the resistance (auxiliary drive resistance) applied to the engine E to drive the auxiliary equipment in the vehicle at the time of deposit burnout control, and sets the target rotational speed. Increase the amount of fuel injection required to maintain. The auxiliary machine is, for example, a headlight 142 or a rear differential switch 94. Since the resistance (load) applied to the engine E increases even when the glow plug 21 is energized as described above, the glow plug 21 may be included in the auxiliary equipment here.

  When such an auxiliary device is driven, for example, when the glow plug 21, the headlight 142, the rear differential 141, or the like is operated, the power of the battery that charges the generated power of the alternator 26 is consumed. As a result, in order to increase the power generation amount of the alternator 26, the work amount of the engine E (that is, auxiliary machine drive resistance) for generating the alternator 26 increases, and the fuel injection amount necessary to maintain the target rotational speed Will increase.

<Control of air-conditioner condenser fan during deposit burnout control>
In the present embodiment, the control device 60 performs control to weaken the output of the air conditioner condenser fan 154 (hereinafter referred to as “capacitor fan 154” as appropriate) during the deposit burnout control, compared with that during normal operation. The refrigerant pressure (refrigerant temperature) on the upstream side of the compressor is increased. By doing this, the amount of work required for the compressor of the air conditioner system connected to the output shaft of the engine E is increased, and the resistance applied to the engine E is increased, so that the fuel necessary to maintain the target rotational speed Increase the injection amount. The “output of the condenser fan 154” is typically defined by the air volume and the air pressure by the condenser fan 154.

  Here, with reference to FIG. 4, the air-conditioning system by embodiment of this invention is demonstrated. FIG. 4 is a schematic configuration diagram showing an air conditioner system according to an embodiment of the present invention.

  As shown in FIG. 4, the air conditioner system 150 includes a refrigerant passage 151 configured to circulate a refrigerant (air conditioner gas), a compressor 152 provided on the refrigerant passage 151, a condenser 153, a condenser fan 154, A receiver 155, an expansion valve 156, an evaporator 157, and a blower fan 158 are included. Specifically, first, the drive shaft 152a of the compressor 152 is connected to the output shaft 201 of the engine E via the belt 202 (the drive shaft 152a of the compressor 152 and the output shaft of the engine E by the air conditioner compressor clutch 159 described above). And the engine E is driven to compress the refrigerant. By such compression by the compressor 152, the refrigerant becomes a semi-liquid state at a relatively high temperature and high pressure.

  Next, the condenser 153 is provided on the refrigerant passage 151 on the downstream side of the compressor 152, and cools the refrigerant supplied from the compressor 152 by blowing air from the condenser fan 154. Such cooling by the capacitor 153 further promotes liquefaction of the refrigerant. Next, the receiver 155 is provided on the refrigerant passage 151 on the downstream side of the condenser 153, separates the refrigerant that has not been liquefied in the condenser 153 from the liquid refrigerant, and removes moisture and impurities with a desiccant and a strainer.

  Next, the expansion valve 156 is provided on the refrigerant passage 151 on the downstream side of the receiver 155, and injects the refrigerant supplied from the receiver 155 toward the evaporator 157 through a minute nozzle hole. Thus, the refrigerant | coolant injected by the evaporator 157 vaporizes at a stretch. Next, the evaporator 157 is provided on the refrigerant passage 151 on the downstream side of the expansion valve 156, and the heat is taken away and cooled by the refrigerant vaporized by the injection from the expansion valve 156. Cold air is created by allowing the wind of the blower fan 158 to pass through the evaporator 157 thus cooled, and this cold air is sent out into the passenger compartment. Then, the refrigerant after passing through the evaporator 157 is supplied to the compressor 152, and the same processing as described above is performed again.

  Next, the relationship among the output of the condenser fan 154, the refrigerant pressure upstream of the compressor 152, and the air conditioner load will be described with reference to FIG.

  FIG. 5A shows a fan duty for driving the condenser fan 154 (which is a duty ratio for controlling the motor of the condenser fan 154 and corresponds to the output of the condenser fan 154 described above), and upstream of the compressor 152. The relationship with the refrigerant pressure on the side is shown. In FIG. 5A, graph G1 shows the relationship between fan duty and refrigerant pressure when the outside air temperature is low, and graph G2 shows the relationship between fan duty and refrigerant pressure when the outside air temperature is high. ing. As shown in the graphs G1 and G2, in both cases where the outside air temperature is low and high, the refrigerant pressure basically decreases as the fan duty increases. In other words, the refrigerant pressure increases as the fan duty decreases. Also, when the outside air temperature is low when viewed at the same fan duty, the refrigerant pressure is lower than when the outside air temperature is high, in other words, when the outside air temperature is high when viewed at the same fan duty, The refrigerant pressure is higher than when the temperature is low.

  On the other hand, FIG. 5B shows the relationship between the refrigerant pressure upstream of the compressor 152 and the air conditioner load (corresponding to torque (load torque) for driving the compressor 152). As shown in FIG. 5B, the air conditioner load increases as the refrigerant pressure increases.

  In the present embodiment, when the control device 60 performs deposit burnout control, the refrigerant pressure on the upstream side of the compressor 152 falls within a predetermined range A11 on the relatively high pressure side (see FIGS. 5A and 5B). In addition, the fan duty of the condenser fan 154 is controlled. Basically, the control device 60 performs control to lower the fan duty during deposit burnout control than during normal operation. In this case, from the relationship between the graph G1 and the graph G2 described above, the control device 60 increases the degree of lowering the fan duty as the outside air temperature is lower so that the refrigerant pressure is appropriately maintained within the predetermined range A11. In other words, the degree of lowering the fan duty is reduced as the outside air temperature is higher.

  When the fan duty of the condenser fan 154 is controlled so that the refrigerant pressure falls within the predetermined range A11 in this way, the air conditioner load increases (see arrow A12 in FIG. 5B). As a result, the resistance applied to the engine E increases, so that the amount of fuel injection necessary to maintain the target rotational speed increases.

  Note that the lower limit value of the predetermined range A11 of the refrigerant pressure is determined according to the air conditioner load at which a desired increase in the fuel injection amount is realized. Further, the upper limit value of the predetermined range A11 of the refrigerant pressure is from the viewpoint of suppressing the operation of the compressor 152 of the air conditioner system 150 due to the refrigerant temperature (corresponding to the refrigerant pressure) becoming too high in summer and the like. It has been established.

  Next, a time chart when the condenser fan 154 is controlled at the time of deposit burnout control in the embodiment of the present invention will be described with reference to FIG. FIG. 6 shows the engine speed, gear stage, accelerator opening, fuel injection timing, combustion center of gravity position (corresponding to the above-described heat generation rate center of gravity position), air conditioner switch state, upstream side of the compressor 152 in order from the top. The refrigerant pressure, the fuel injection amount, the surface temperature of the fuel injection valve 20, and the deposit amount deposited on the fuel injection valve 20 (particularly, the deposit amount deposited in the recess 20d of the injection hole 20c) are shown.

  As shown in FIG. 6, the control device 60 performs deposit burning control for burning the deposit accumulated on the fuel injection valve 20 from time t11 to time t12 (for example, 120 seconds). In the present embodiment, from the viewpoint of ensuring safety, the control device 60 performs deposit burnout control in a state where the accelerator opening is 0 (that is, the accelerator is off) and the gear stage of the transmission is set to neutral. I do. More specifically, the control device 60 performs deposit burnout control during maintenance of the vehicle and when the vehicle is not traveling.

  When the deposit burnout control is started at time t11, the control device 60 advances the fuel injection timing of the fuel injection valve 20, advances the combustion center of gravity, and lowers the output of the condenser fan 154 ( Reduce the fan duty) and increase the refrigerant pressure upstream of the compressor 152. Although the increase in the refrigerant pressure increases the resistance applied to the engine E, the actual engine speed tends to decrease. However, the control device 60 appropriately sets the actual engine speed to the target engine speed. Therefore, the fuel injection amount of the fuel injection valve 20 is increased.

  Due to the advance of the fuel injection timing and the increase of the fuel injection amount due to the increase of the refrigerant pressure, the combustion gas temperature is greatly increased, and the surface temperature of the fuel injection valve 20 is greatly increased. As a result, the deposit accumulated in the recess 20d of the injection hole 20c of the fuel injection valve 20 is effectively burned out. Thereafter, at time t12, the control device 60 ends the control for advancing the fuel injection timing and the control for increasing the refrigerant pressure to end the deposit burnout control, that is, the fuel injection timing before starting the deposit burnout control and Return to refrigerant pressure.

  Control of the condenser fan 154 at the time of deposit burnout control as described above is preferably performed in a state where the air conditioner system 150 is set to heating. This is because if the control is performed in the mid-winter state with the air conditioner system 150 set to cooling, the evaporator 157 is too cold and the air after passing through the evaporator 157 freezes, and the operation of the air conditioner system 150 may stop. Because there is.

<Deposit accumulation judgment of fuel injection valve>
When deposit accumulates in the recess 20 d of the injection hole 20 c of the fuel injection valve 20, the fuel injected from the fuel injection valve 20 is not easily diffused into the combustion chamber 17. Therefore, homogeneous combustion is not performed in the combustion chamber 17 and PM (soot) is easily generated, and the rate at which PM is collected in the DPF 46 is increased. As a result, the process (DPF regeneration) for burning and removing the PM collected by the DPF 46 tends to be executed with high frequency. Therefore, in the present embodiment, the control device 60 determines whether or not deposits are accumulated on the fuel injection valve 20 based on the execution frequency of DPF regeneration. In particular, in the present embodiment, the control device 60 obtains a distance (corresponding to an interval at which DPF regeneration is performed) that the vehicle has traveled since DPF regeneration was performed last time until DPF regeneration is performed this time. By comparing the travel distance and a predetermined determination distance, it is determined whether or not deposits have accumulated on the fuel injection valve 20. In one example, the control device 60 determines that deposits have accumulated on the fuel injection valve 20 when the travel distance corresponding to the interval at which DPF regeneration is performed is less than the determination distance. Details of the deposit accumulation determination method according to the present embodiment will be described later.

<Control flow>
Next, a specific flow of control (processing) according to the embodiment of the present invention will be described.

  First, with reference to FIG. 7, the control (main control) mainly performed in the embodiment of the present invention will be described. FIG. 7 is a flowchart showing main control according to the embodiment of the present invention. In this flow, in addition to the control for realizing the target oxygen concentration and the target intake air temperature according to the required injection amount, a deposit for determining whether or not deposits are accumulated on the fuel injection valve 20 Judgment processing is performed. The flow is typically repeatedly executed at a predetermined cycle by the control device 60 after the ignition of the vehicle is turned on.

  First, in step S11, the control device 60 acquires at least one or more of the signals S94 to S122 output from the various sensors 94 to 122 described above.

  Next, in step S <b> 12, the control device 60 sets a target torque to be output from the engine E based on the accelerator opening detected by the accelerator opening sensor 100. In step S13, the control device 60 sets a required injection amount to be injected from the fuel injection valve 20 based on the target torque set in step S12 and the engine speed.

  Next, in step S14, the control device 60 determines the fuel injection pattern, fuel pressure, target oxygen concentration, target intake air temperature, and EGR control based on the required injection amount set in step S13 and the engine speed. A mode (a mode in which both or one of the high pressure EGR device 43 and the low pressure EGR device 48 is operated, or a mode in which neither the high pressure EGR device 43 nor the low pressure EGR device 48 is operated) is set.

  Next, in step S15, the control device 60 sets a state quantity that realizes the target oxygen concentration and the target intake air temperature set in step S14. For example, this state quantity includes the amount of exhaust gas recirculated to the intake system IN by the high pressure EGR device 43 (high pressure EGR gas amount) and the amount of exhaust gas recirculated to the intake system IN by the low pressure EGR device 48 (low pressure EGR gas amount). And a supercharging pressure by the turbocharger 5 is included.

  Next, in step S <b> 16, the control device 60 controls each actuator that drives each component of the engine system 200 based on the state quantity set in step S <b> 15. In this case, the control device 60 sets a limit value or a limit range according to the state quantity, sets a control amount of each actuator such that the state value complies with the limit value or the limit range, and executes control. .

  Further, in parallel with the processes in steps S11 to S16 described above, the control device 60 executes a deposit determination process for determining whether or not deposits are accumulated on the fuel injection valve 20 in step S17.

  Next, the deposit determination process according to the embodiment of the present invention will be specifically described with reference to FIG. FIG. 8 is a flowchart showing deposit determination processing according to the embodiment of the present invention. This flow is executed by the control device 60 in step S17 of FIG.

  First, in step S <b> 21, the control device 60 acquires the DPF differential pressure (the difference in exhaust pressure between the upstream side and the downstream side of the DPF 46) detected by the DPF differential pressure sensor 120.

  If the result of determination in step S22 is that the DPF differential pressure is less than the predetermined pressure (step S22: No), the process ends. In this case, since the amount of PM collected by the DPF 46 does not exceed a predetermined amount, the control device 60 determines that the DPF regeneration is not in a situation. On the other hand, when the DPF differential pressure is equal to or higher than the predetermined pressure (step S22: Yes), the process proceeds to step S23, where the control device 60 determines that the DPF regeneration should be performed and sets the DPF regeneration execution flag. Set to on and issue a DPF regeneration execution request. In this case, the control device 60 executes control for raising the temperature of the DPF 46 to a temperature at which the PM collected by the DPF 46 can be removed by combustion.

  Next, in step S24, the control device 60 acquires the travel distance when the DPF regeneration execution flag is turned on this time, in other words, the travel distance when the DPF regeneration is performed this time. This travel distance is stored in a predetermined memory or the like. In step S25, the control device 60 obtains the distance traveled when the DPF regeneration execution flag was turned on this time and the distance traveled when the DPF regeneration execution flag was previously turned on, acquired in step S24. Calculate the difference. That is, the control device 60 calculates the distance traveled by the vehicle from the previous execution of DPF regeneration to the current execution of DPF regeneration. Hereinafter, the distance is appropriately referred to as “calculated travel distance”.

  Next, in step S26, the control device 60 determines whether or not the calculated travel distance obtained in step S25 is less than 50 km. As a result of the determination, if the calculated travel distance is less than 50 km (step S26: Yes), the process proceeds to step S27, and the control device 60 increments a predetermined counter (50 km counter) by 1. In step S28, the control device 60 determines whether or not the 50 km counter is 3 or more. As a result of the determination, if the 50 km counter is 3 or more (step S28: Yes), the process proceeds to step S35. In this case, since the DPF regeneration has been executed at a relatively high frequency, the control device 60 determines that the deposit has accumulated on the fuel injection valve 20, and turns on the deposit burnout flag for burning this deposit. (Step S35). Then, the process proceeds to step S <b> 36, and the control device 60 turns on a warning lamp indicating that deposits are accumulated on the fuel injection valve 20.

  On the other hand, when the calculated travel distance obtained in step S25 is 50 km or more (step S26: No), the process proceeds to step S29, and the control device 60 determines whether the calculated travel distance is less than 70 km. As a result of the determination, if the calculated travel distance is less than 70 km (step S29: Yes), the process proceeds to step S30, and the control device 60 increments a predetermined counter (70 km counter) by one. Then, the process proceeds to step S31, and the control device 60 determines whether or not the 70 km counter is 20 or more. As a result of the determination, when the 70 km counter is 20 or more (step S31: Yes), the process proceeds to step S35. Also in this case, since the DPF regeneration is executed at a relatively high frequency, the control device 60 determines that the deposit is accumulated on the fuel injection valve 20, and sets the deposit burnout flag to ON (step S35). . Then, the process proceeds to step S <b> 36, and the control device 60 turns on a warning lamp indicating that deposits are accumulated on the fuel injection valve 20.

  On the other hand, when the calculated travel distance obtained in step S25 is 70 km or more (step S29: No), the process proceeds to step S32, and the control device 60 determines whether the calculated travel distance is less than 100 km. As a result of the determination, if the calculated travel distance is less than 100 km (step S32: Yes), the process proceeds to step S33, and the control device 60 increments a predetermined counter (100 km counter) by one. Then, the process proceeds to step S34, and the control device 60 determines whether or not the 100 km counter is 50 or more. As a result of the determination, if the 100 km counter is 50 or more (step S34: Yes), the process proceeds to step S35. Also in this case, since the DPF regeneration is executed at a relatively high frequency, the control device 60 determines that the deposit is accumulated on the fuel injection valve 20, and sets the deposit burnout flag to ON (step S35). . Then, the process proceeds to step S <b> 36, and the control device 60 turns on a warning lamp indicating that deposits are accumulated on the fuel injection valve 20.

  On the other hand, when the calculated travel distance obtained in step S25 is 100 km or more (step S32: No), the process ends. In this case, since the execution interval of DPF regeneration is long, the control device 60 determines that no deposit is accumulated on the fuel injection valve 20.

  When the 50 km counter is less than 3 (step S28: No), the 70 km counter is less than 20 (step S31: No), and the 100 km counter is less than 50 (step S34: No). In either case, the process ends. Also in this case, the control device 60 determines that no deposit is accumulated on the fuel injection valve 20. In the situation where the process proceeds to step S28, step S31 and step S34, since the execution interval of DPF regeneration is relatively short, there is a possibility that deposits are accumulated on the fuel injection valve 20, but deposits on the fuel injection valve 20 are accumulated. There is a possibility that an execution request for DPF regeneration has been issued due to other factors (for example, an operation that frequently switches between depression and depression of the accelerator pedal 95 or an operation that operates the engine E for a long time in a high load range). Conceivable. Therefore, in the case described above, control device 60 does not set the deposit burnout flag to ON. By doing so, erroneous determination of deposit accumulation in the fuel injection valve 20 is prevented.

  Thus, in this embodiment, the travel distance from when DPF regeneration is executed last time until DPF regeneration is executed this time is determined using a plurality of determination distances (50 km, 70 km, and 100 km), and the plurality of these distances are determined. A plurality of counters (a 50 km counter, a 70 km counter, and a 100 km counter) corresponding to the determination distance are defined, and the number of times the DPF regeneration is executed is separately counted. Then, using a plurality of determination values corresponding to the plurality of counters, specifically, a determination value that decreases as the determination distance corresponding to the counter decreases (for a counter for 50 km, for 3, 70 km) 20 is used for the counter and 50 is used for the 100 km counter, and it is determined whether or not deposits are accumulated on the fuel injection valve 20. By doing so, deposit accumulation in the fuel injection valve 20 is accurately determined.

  The 50 km counter, the 70 km counter, and the 100 km counter are each reset after execution of deposit burnout control, which will be described later, that is, set to 0.

  Next, deposit burnout control according to the embodiment of the present invention will be specifically described with reference to FIG. FIG. 9 is a flowchart showing deposit burnout control according to the embodiment of the present invention. This flow is executed by the control device 60 when the vehicle is stored in the dealer and maintenance is performed (assuming that the vehicle is in a non-traveling state). Prior to starting the flow, the control device 60 acquires various types of information on the vehicle in advance.

  First, in step S41, control device 60 determines whether or not a predetermined operation for starting deposit burnout control has been performed by a mechanic or the like. As a result of this determination, when the predetermined operation is performed (step S41: Yes), the process proceeds to step S42, and when the predetermined operation is not performed (step S41: No), the process ends.

  Next, in step S42, control device 60 determines whether or not the deposit burnout flag is on. This deposit burnout flag is set in the deposit determination process of FIG. As a result of the determination in step S42, if the deposit burnout flag is on (step S42: Yes), the process proceeds to step S43. If the deposit burnout flag is not on (step S42: No), the process ends.

  Next, in step S43, control device 60 determines whether or not the gear position of the transmission is set to neutral. As a result of this determination, if the gear stage is set to neutral (step S43: Yes), the process proceeds to step S44. If the gear stage is not set to neutral (step S43: No), the process ends. . In the present embodiment, from the viewpoint of ensuring safety, the deposit burnout control is performed in a state where the output of the engine E is not transmitted to the wheels.

  Next, in step S44, the control device 60 determines whether or not the accelerator pedal 95 is depressed, that is, whether or not the accelerator is off, based on the output of the accelerator opening sensor 100. As a result of the determination, if the accelerator is off (step S44: Yes), the process proceeds to step S45. If the accelerator is not off (step S44: No), the process ends. In the present embodiment, from the viewpoint of ensuring safety, the deposit burnout control is performed in the accelerator off state.

  Next, in step S45, the control device 60 determines that the water temperature (cooling water temperature) and the oil temperature are equal to or higher than a predetermined temperature (for example, 80 to 90 ° C.) based on the outputs of the cooling water temperature sensor 109 and the hydraulic pressure / oil temperature sensor 111. It is determined whether or not there is. As a result of the determination, when the water temperature and the oil temperature are equal to or higher than the predetermined temperature (step S45: Yes), the process proceeds to step S46, and when the water temperature and the oil temperature are lower than the predetermined temperature (step S45: No), the process is performed. finish. In the present embodiment, the deposit burnout control is performed in a state where the engine E is heated up to a temperature at which the deposit of the fuel injection valve 20 can be burned out efficiently.

  Next, in step S46, the control device 60 determines whether or not the headlight switch 95 is on. As a result of this determination, if the headlight switch 95 is on (step S46: Yes), the process proceeds to step S47. If the headlight switch 95 is off (step S46: No), the process ends. In the present embodiment, the auxiliary drive resistance applied to the engine E is increased by the power consumption due to the lighting of the headlight 142 as an auxiliary machine (specifically, the power generation of the alternator 26 by the power consumption of the headlight 142). The deposit burnout control is performed when the amount increases and the load of the engine E for generating the alternator 26 increases. From the viewpoint of effectively increasing the auxiliary machine driving resistance by the headlight 142, it is preferable to set the headlight 142 to a high beam (generally, the power consumption of the headlight 142 tends to increase when the high light beam is set). .

  Next, in step S47, the control device 60 determines whether or not the air conditioner switch 96 is on. As a result of the determination, if the air conditioner switch 96 is on (step S47: Yes), the process proceeds to step S48. If the air conditioner switch 96 is off (step S47: No), the process ends. In the present embodiment, the load applied to the engine E to operate the air conditioner system 150 is high (specifically, since the compressor 152 of the air conditioner system 150 is operated by the engine E, The deposit burnout control is performed when the load of the engine E increases during operation.

  Next, in step S48, the control device 60 connects the air conditioner compressor clutch 159 provided in the compressor 152 of the air conditioner system 150 because the air conditioner switch 96 is turned on. In this way, the output of the engine E is transmitted to the compressor 152 of the air conditioner system 150. Then, the process proceeds to step S49.

  Next, in step S49, the control device 60 determines whether or not the rear differential switch 94 is on. If the result of this determination is that the rear differential switch 94 is on (step S49: Yes), the process proceeds to step S50. If the rear differential switch 94 is off (step S49: No), the process ends. In the present embodiment, a state in which the auxiliary drive resistance applied to the engine E is high due to power consumption by energizing the rear differential 141 as an auxiliary machine (specifically, the power generation amount of the alternator 26 by the power consumption of the rear differential 141). And the load on the engine E for generating power from the alternator 26 is increased).

  Next, in step S50, the control device 60 determines whether the air volume of the air conditioner system 150 (that is, the output of the blower fan 158) is maximum based on the output of the air volume changeover switch 97 of the air conditioner system 150. As a result of this determination, when the air volume of the air conditioner system 150 is maximum (step S50: Yes), the process proceeds to step S51. When the air volume of the air conditioner system 150 is not maximum (step S50: No), the process ends. In the present embodiment, in order to increase the auxiliary machine drive resistance, the air volume of the air conditioner system 150 is maximized (specifically, the power generation amount of the alternator 26 increases due to the power consumption of the blower fan 158, and the alternator 26 generates power). In this case, the deposit burnout control is performed.

  When all the above-described conditions of steps S41 to S47, S49, and S50 are satisfied, the control device 60 performs control for burning out deposits deposited on the fuel injection valve 20 after step S51. First, in step S51, the control device 60 sets the target rotational speed to 1750 rpm. The control device 60 sets such a relatively low rotation speed as the target rotation speed, thereby maintaining a relatively slow piston speed and ensuring the time required for fuel injection and diffusion. The control device 60 applies the target rotational speed and executes the main control shown in FIG. 7 so that the actual engine rotational speed is maintained at the target rotational speed.

Next, in step S <b> 52, the control device 60 performs control for energizing the glow plug 21, that is, performs control for applying current / voltage to the glow plug 21. By doing so, deterioration of fuel ignitability and incomplete combustion due to the advance of the fuel injection timing are suppressed. In addition, by increasing the resistance imparted to the engine E by the power consumption of the glow plug 21 (specifically, the power generation amount of the alternator 26 is increased by energization of the glow plug 21 and the load on the engine E is increased). The in-cylinder gas temperature is raised by increasing the fuel injection amount necessary to maintain the rotational speed.
Specifically, in step S52, the control device 60 sets a substantially upper limit temperature within a range in which the reliability of the glow plug 21 is appropriately secured as a target temperature (for example, 1200 ° C.), and the glow plug 21 sets the target temperature. Energization control is performed so that In this case, the control device 60 estimates the temperature of the glow plug 21 using a predetermined model based on the water temperature, the intake air temperature, the intake air amount, the engine speed, the fuel injection amount, and the like, and compares the estimated temperature with the target temperature. However, energization control is performed so that the glow plug 21 is maintained at the target temperature. By doing so, failure of the glow plug 21 due to the temperature of the glow plug 21 exceeding the target temperature relatively greatly is suppressed.

Next, in step S53, the control device 60 performs control to weaken the output of the condenser fan 154 than during normal operation so as to increase the refrigerant pressure (refrigerant temperature) on the upstream side of the compressor 152 of the air conditioner system 150. For example, the control device 60 performs control to reduce the duty for driving the capacitor fan 154. By doing this, the work amount of the compressor 152 connected to the engine E (the work amount for compressing the refrigerant) is increased, and the resistance applied to the engine E is increased, thereby maintaining the target rotational speed. The amount of fuel injection required for this is increased.
Specifically, in step S53, the control device 60 controls the output of the condenser fan 154 based on the outside air temperature so that the refrigerant pressure upstream of the compressor 152 falls within a predetermined range A11 on the relatively high pressure side. In this case, the control device 60 basically sets the output of the condenser fan 154 lower than that during normal operation, but increases the output of the condenser fan 154 as the outside temperature increases (that is, as the outside temperature increases). The degree of lowering the output of the condenser fan 154 is reduced). By doing so, it is possible to prevent the compressor 152 of the air conditioner system 150 from being stopped due to the refrigerant temperature becoming too high in summer or the like.
In addition, the control device 60 performs the control of the condenser fan 154 as described above in a state where the air conditioner system 150 is set to heating. This is because if the control is performed in the mid-winter state with the air conditioner system 150 set to cooling, the evaporator 157 is too cold and the air after passing through the evaporator 157 freezes, and the operation of the air conditioner system 150 may stop. Because there is.

  Next, in step S54, the control device 60 fully closes both the high pressure EGR valve 43b of the high pressure EGR device 43 and the low pressure EGR valve 48c of the low pressure EGR device 48 in order to stop the recirculation of the EGR gas to the intake system IN. Control. By doing so, the oxygen concentration of the gas supplied to the engine E is increased, and the maximum in-cylinder temperature is effectively increased (in other words, the heat generation rate is increased). In addition, the fuel injection amount necessary to maintain the target rotational speed is increased due to an increase in pump loss of the engine E resulting from the reduction in the EGR gas amount.

  Next, in step S55, the control device 60 controls the VGT opening degree (opening degree of the flap 5c) of the turbocharger 5 to the closed side so as to increase the supercharging pressure by the turbocharger 5. In this way, the in-cylinder pressure is increased to improve the ignition environment in the combustion chamber 17, and the deterioration of fuel ignitability and incomplete combustion due to the advance of the fuel injection timing are suppressed. . In addition, the amount of fuel injection required to maintain the target rotational speed is increased by increasing the resistance of the piston 23 due to the increase in the supercharging pressure.

  Next, in step S56, the control device 60 increases the in-cylinder temperature at the compression top dead center (in-cylinder maximum temperature) so as to increase the period during which the combustion gas is compressed in the combustion chamber 17. Advance the fuel injection timing. In this case, the control device 60 advances the fuel injection timing (that is, limits the degree to which the fuel injection timing is advanced) within a range in which the ignitability of the fuel is ensured and incomplete combustion does not occur. Specifically, the control device 60 advances the fuel injection timing in accordance with the geometric compression ratio of the engine E. More specifically, based on the above two expressions indicating the range of the advance amount, the fuel injection timing corresponding to the geometric compression ratio of the target engine E is determined in advance. The fuel injection timing determined as described above is applied.

  Next, in step S57, control device 60 determines whether or not a predetermined time (for example, 120 seconds) has elapsed since the start of deposit burnout control. As a result of this determination, if the predetermined time has elapsed (step S57: Yes), the process proceeds to step S58, where the control device 60 ends the deposit burnout control and sets the deposit burnout flag to OFF. On the other hand, when the predetermined time has not elapsed (step S57: No), the process returns to step S57. In this case, the control device 60 repeats the determination in step S57 until a predetermined time has elapsed.

  In the deposit burnout control described above, the operation condition of the control is that the rear differential switch 94, the air conditioner switch 96, the headlight switch 95, and the air volume changeover switch 97 are manually operated by a mechanic (step S46, (See S47, S49, and S50). In another example, the manual operation by such a mechanic may not be set as an execution condition, and the rear differential 141, the headlight 142, and the air conditioner system 150 may be automatically controlled when the deposit burnout control is executed. In other words, when the deposit burnout control is executed, the rear differential 141, the air conditioner system 150, and the headlight 142 are automatically turned on, and the air volume of the air conditioner system 150 is automatically maximized. .

<Effect>
Next, functions and effects of the vehicle control method and control system according to the embodiment of the present invention will be described.

  In the present embodiment, the control device 60 advances the fuel injection timing of the fuel injection valve 20 at the time of deposit burnout control, and lowers the output of the condenser fan 154 so that the refrigerant pressure upstream of the compressor 152 increases. I do. As a result, the work amount of the compressor 152 increases, and the resistance applied to the engine E increases, so that the fuel injection amount necessary to maintain the target rotational speed increases. Therefore, according to the present embodiment, a relatively large amount of fuel can be burned to effectively increase the in-cylinder maximum temperature, and deposits deposited on the fuel injection valve 20 (particularly, deposited on the recesses 20d of the injection holes 20c). It becomes possible to burn out the deposit).

  In addition, according to the present embodiment, the control device 60 performs such deposit burnout control during maintenance of the vehicle and when the vehicle is not traveling, and thus gives a sense of incongruity (noise, etc.) by performing the control during actual vehicle traveling. Can be suppressed.

  Further, in the present embodiment, the control device 60 increases the degree of lowering the output of the condenser fan 154 as the outside air temperature is lower, in other words, the degree of lowering the output of the condenser fan 154 as the outside air temperature is higher. Make it smaller. Accordingly, the refrigerant pressure upstream of the compressor 152 can be appropriately set within the predetermined range A11 on the desired high pressure side regardless of the outside air temperature, and the fuel injection amount can be appropriately increased as described above. it can. In addition, in summer and the like, it is possible to prevent the refrigerant temperature (corresponding to the refrigerant pressure) from becoming too high and the compressor 152 of the air conditioner system 150 from being stopped.

  Moreover, in this embodiment, the control apparatus 60 performs the control of the condenser fan 154 at the time of deposit burnout control as described above in a state where the air conditioner system 150 is set to heating. Thereby, the stop of the operation of the air conditioner system 150 due to the freezing of the air after passing through the evaporator 157, which can be generated by performing the control in the state where the air conditioner system 150 is set to cooling in midwinter or the like, can be suppressed.

<Modification>
Next, a modification of the above embodiment will be described. Note that the various controls and processes described in the above-described embodiments are also applied as appropriate in the modified examples described below.

  In the above-described embodiment, when it is determined that the deposit is accumulated on the fuel injection valve 20, the control device 60 performs the deposit burning control for burning the deposit when the vehicle is being maintained and when the vehicle is not traveling. . In the modification, the control device 60 suppresses deposit accumulation for suppressing deposit accumulation on the fuel injection valve 20 when a request for increasing the engine resistance applied to the engine E is issued when the vehicle is traveling. Control may be performed. In particular, in this modification, the control device 60 issues a request to increase engine resistance and performs deposit accumulation suppression control in an operating state where deposits are highly likely to accumulate on the fuel injection valve 20. Specifically, the control device 60, when traveling, when the combustion gas temperature in the combustion chamber 17 is lower than a predetermined temperature (typically, the engine E is warming up, at this time, the fuel injection valve 20 In addition, the fuel injection timing of the fuel injection valve 20 is advanced, and the output of the condenser fan 154 is controlled to increase the refrigerant pressure upstream of the compressor 152.

  With reference to FIG. 10, the deposit accumulation suppression control according to the modification of the embodiment of the present invention will be specifically described. FIG. 10 shows a time chart when the capacitor fan 154 is controlled during deposit accumulation suppression control in a modification of the embodiment of the present invention. Specifically, FIG. 10 shows, in order from the top, engine speed, gear stage, accelerator opening, fuel injection timing, combustion center of gravity position (corresponding to the above-mentioned heat generation rate center of gravity position), air conditioner switch state, compressor The refrigerant pressure upstream of 152, the fuel injection amount, the surface temperature of the fuel injection valve 20, and the deposit amount deposited on the fuel injection valve 20 (particularly, the deposit amount deposited in the recess 20d of the injection hole 20c) are shown. In FIG. 10, regarding the fuel injection timing and the combustion gravity center position, the solid line indicates the fuel injection timing and the combustion gravity center position applied in the deposit accumulation suppression control according to the present modification, and the broken line indicates the deposit burnout control according to the above-described embodiment. 2 shows the fuel injection timing and the position of the center of gravity of combustion applied. In addition, regarding the deposit amount, the solid line indicates the deposit amount when the deposit accumulation suppression control according to this modification is performed, and the broken line indicates the deposit amount when the deposit accumulation suppression control is not performed.

  As shown in FIG. 10, the control device 60 starts deposit accumulation suppression control for suppressing deposit accumulation on the fuel injection valve 20 from time t21. Specifically, the control device 60 estimates the combustion gas temperature in the combustion chamber 17 using a predetermined model or the like, and performs deposit accumulation suppression control when the estimated combustion gas temperature is lower than the predetermined temperature. Typically, control device 60 performs deposit accumulation suppression control while engine E is not warmed up and the vehicle is traveling at a low speed (that is, during light load operation).

When the deposit accumulation suppression control is started at time t21, the control device 60 advances the fuel injection timing of the fuel injection valve 20 to advance the combustion gravity center position. In this case, the control device 60 makes the advance amount of the fuel injection timing smaller than when performing the above-described deposit burnout control. By doing so, it is possible to suppress the deterioration of combustion stability and the occurrence of a sense of incongruity (noise, etc.) caused by the advance of the fuel injection timing during vehicle travel in which deposit accumulation suppression control is performed. In addition, the control device 60 advances the fuel injection timing and simultaneously reduces the output of the condenser fan 154 (decreases the fan duty) and increases the refrigerant pressure on the upstream side of the compressor 152. Although the increase in the refrigerant pressure increases the resistance applied to the engine E, the actual engine speed tends to decrease. However, the control device 60 appropriately sets the actual engine speed to the target engine speed. Therefore, the fuel injection amount of the fuel injection valve 20 is increased.
When the controller 60 reduces the output of the condenser fan 154, the degree to which the output of the condenser fan 154 is reduced as the difference (absolute value) between the combustion gas temperature estimated as described above and the predetermined temperature is smaller. Make it smaller. By doing so, an increase in resistance of the engine E due to an increase in the refrigerant pressure is minimized, and a deterioration in fuel consumption due to deposit accumulation suppression control is suppressed as much as possible.

  The combustion gas temperature rises and the surface temperature of the fuel injection valve 20 rises due to the advance of the fuel injection timing and the increase of the fuel injection amount due to the increase of the refrigerant pressure. As a result, deposit accumulation in the recess 20d of the injection hole 20c of the fuel injection valve 20 is appropriately suppressed as compared with the case where the deposit accumulation suppression control is not performed. After that, at time t22, the control device 60 ends the control for advancing the fuel injection timing and the control for increasing the refrigerant pressure to end the deposit accumulation suppression control, that is, the fuel before the start of the deposit accumulation suppression control. Return to injection timing and refrigerant pressure. Basically, the control device 60 ends the deposit accumulation suppression control when the combustion gas temperature becomes equal to or higher than a predetermined temperature. In addition, when the water temperature becomes equal to or higher than a predetermined temperature, or when the DOC 45 and / or the DPF 46 becomes equal to or higher than the predetermined temperature, the deposit accumulation suppression control may be ended.

  As described above, in the present modification, the control device 60 advances the fuel injection timing of the fuel injection valve 20 and the refrigerant pressure upstream of the compressor 152 when the combustion gas temperature is lower than the predetermined temperature. Is controlled so as to decrease the output of the condenser fan 154 so that the voltage becomes higher. As a result, the work amount of the compressor 152 increases, and the resistance applied to the engine E increases, so that the fuel injection amount necessary to maintain the target rotational speed increases. Therefore, according to this modification, a relatively large amount of fuel can be burned to effectively increase the in-cylinder maximum temperature, and deposit accumulation in the fuel injection valve 2 (particularly deposit accumulation in the recess 20d of the injection hole 20c). (Deposition) can be suppressed in advance.

  In the above-described modification, in the deposit accumulation suppression control, in addition to the control of the condenser fan 154 for increasing the refrigerant pressure, the control for advancing the fuel injection timing is performed. However, in the further modification, the deposit accumulation suppression control is performed. In the accumulation suppression control, the control of the condenser fan 154 for increasing the refrigerant pressure may be performed without performing the control for advancing the fuel injection timing. In such a case, it is possible to reliably suppress the deterioration of combustion stability and the occurrence of a sense of incongruity (such as noise) caused by the advance angle of the fuel injection timing.

  In addition, about an above described modification, it is not limited to application to a diesel engine, It can apply also to a gasoline engine. In addition, the modification is not limited to application to the fuel injection valve 20 that directly injects fuel into the combustion chamber 17, and the fuel is injected into a passage connected to the combustion chamber 17 (that is, port injection). It can also be applied to a fuel injection valve.

DESCRIPTION OF SYMBOLS 1 Intake passage 5 Turbocharger 20 Fuel injection valve 21 Glow plug 41 Exhaust passage 43 High pressure EGR device 45 DOC
46 DPF
48 Low-pressure EGR device 60 Control device 150 Air-conditioner system 151 Refrigerant passage 152 Compressor 153 Condenser 154 Air-conditioner condenser fan 157 Evaporator 200 Engine system E Engine

Claims (12)

A diesel engine having a fuel injection valve for directly injecting fuel into the combustion chamber;
An air conditioner system driven by the diesel engine, the air conditioner system being provided on the refrigerant passage for circulating and flowing the refrigerant, and driven by the diesel engine so as to compress the refrigerant. A compressor that is provided on the refrigerant passage downstream of the compressor, cools the refrigerant compressed by the compressor, a condenser fan that blows air toward the condenser, and the refrigerant downstream of the condenser An air conditioner system provided on a passage and configured to vaporize a refrigerant from the condenser, and a vehicle control method comprising:
Controlling the fuel injection amount of the fuel injection valve based on the required torque during vehicle travel;
Determining whether deposits are deposited in the combustion chamber;
When it is determined that the deposit is accumulated, the fuel injection timing of the fuel injection valve is advanced and the refrigerant pressure on the upstream side of the compressor is compared with the case where it is not determined that the deposit is accumulated. Performing a control to reduce the output of the capacitor fan so that the
Have
The vehicle control method is characterized in that the control for advancing the fuel injection timing and reducing the output of the condenser fan is performed during maintenance of the vehicle and when the vehicle is not running. An engine having a fuel injection valve for supplying fuel into the combustion chamber;
An air conditioner system driven by the engine, wherein the air conditioner system is provided with a refrigerant passage for circulating and flowing the refrigerant, and a compressor provided on the refrigerant passage and driven by the engine to compress the refrigerant. A condenser that is provided on the refrigerant passage on the downstream side of the compressor and that cools the refrigerant compressed by the compressor, a condenser fan that blows air toward the condenser, and the refrigerant passage on the downstream side of the condenser An air conditioner system comprising: an evaporator that vaporizes refrigerant from the condenser; and a vehicle control method comprising:
Controlling the fuel injection amount of the fuel injection valve based on the required torque during vehicle travel;
The output of the condenser fan is such that the refrigerant pressure on the upstream side of the compressor is higher when a request for increasing the engine resistance applied to the engine is issued than when a request for increasing the engine resistance is not issued. A step of performing control to reduce
A vehicle control method characterized by comprising: A diesel engine having a fuel injection valve for directly injecting fuel into the combustion chamber;
An air conditioner system driven by the diesel engine, the air conditioner system being provided on the refrigerant passage for circulating and flowing the refrigerant, and driven by the diesel engine so as to compress the refrigerant. A compressor that is provided on the refrigerant passage downstream of the compressor, cools the refrigerant compressed by the compressor, a condenser fan that blows air toward the condenser, and the refrigerant downstream of the condenser An air conditioner system provided on a passage and configured to vaporize a refrigerant from the condenser, and a vehicle control method comprising:
Controlling the fuel injection amount of the fuel injection valve based on the required torque during vehicle travel;
Determining whether deposits are deposited in the combustion chamber;
When it is determined that the deposit is accumulated, the fuel injection timing of the fuel injection valve is advanced and the refrigerant pressure on the upstream side of the compressor is compared with the case where it is not determined that the deposit is accumulated. Performing a first control to reduce the output of the condenser fan so as to increase
When the demand for increasing the engine resistance applied to the diesel engine is issued, the fuel injection timing of the fuel injection valve is advanced and the upstream side of the compressor is compared with the case where the demand for increasing the engine resistance is not issued. Performing a second control to reduce the output of the condenser fan so that the refrigerant pressure on the side increases,
Have
The first control is performed when the vehicle is being maintained and not running, and the second control is performed when the vehicle is running,
The vehicle control method according to claim 1, wherein an amount by which the fuel injection timing is advanced in the second control is smaller than an amount by which the fuel injection timing is advanced in the first control.   4. The method according to claim 2, further comprising a step of estimating a combustion gas temperature in the combustion chamber and reducing a degree of decreasing the output of the condenser fan as a difference between the combustion gas temperature and a predetermined temperature is smaller. Vehicle control method.   The vehicle control method according to any one of claims 1 to 4, further comprising a step of increasing a degree of decreasing the output of the condenser fan as the outside air temperature is lower.   The vehicle control according to any one of claims 1 to 5, wherein the control for advancing the fuel injection timing and reducing the output of the condenser fan is performed in a state where the air conditioning system is set to heating. Method. A diesel engine having a fuel injection valve for directly injecting fuel into the combustion chamber;
An air conditioner system driven by the diesel engine, the air conditioner system being provided on the refrigerant passage for circulating and flowing the refrigerant, and driven by the diesel engine so as to compress the refrigerant. A compressor that is provided on the refrigerant passage downstream of the compressor, cools the refrigerant compressed by the compressor, a condenser fan that blows air toward the condenser, and the refrigerant downstream of the condenser An evaporator provided on a passage and vaporizing a refrigerant from the condenser;
A control system for controlling the fuel injection valve and the air conditioner system;
The controller is
Controlling the fuel injection amount of the fuel injection valve based on the required torque during vehicle travel,
Determining whether deposits are deposited in the combustion chamber;
When it is determined that the deposit is accumulated, the fuel injection timing of the fuel injection valve is advanced and the refrigerant pressure on the upstream side of the compressor is increased compared to the case where it is not determined that the deposit is accumulated. Control is performed to reduce the output of the condenser fan so as to increase, and this control is configured to be performed when the vehicle is being maintained and not running,
A vehicle control system. An engine having a fuel injection valve for supplying fuel into the combustion chamber;
An air conditioner system driven by the engine, wherein the air conditioner system is provided with a refrigerant passage for circulating and flowing the refrigerant, and a compressor provided on the refrigerant passage and driven by the engine to compress the refrigerant. A condenser that is provided on the refrigerant passage on the downstream side of the compressor and that cools the refrigerant compressed by the compressor, a condenser fan that blows air toward the condenser, and the refrigerant passage on the downstream side of the condenser And an evaporator that vaporizes the refrigerant from the condenser, and the air conditioning system,
A control system for controlling the fuel injection valve and the air conditioner system;
The controller is
Controlling the fuel injection amount of the fuel injection valve based on the required torque during vehicle travel,
The output of the condenser fan is such that the refrigerant pressure on the upstream side of the compressor is higher when a request for increasing the engine resistance applied to the engine is issued than when a request for increasing the engine resistance is not issued. Configured to perform control to reduce the
A vehicle control system. A diesel engine having a fuel injection valve for directly injecting fuel into the combustion chamber;
An air conditioner system driven by the diesel engine, the air conditioner system being provided on the refrigerant passage for circulating and flowing the refrigerant, and driven by the diesel engine so as to compress the refrigerant. A compressor that is provided on the refrigerant passage downstream of the compressor, cools the refrigerant compressed by the compressor, a condenser fan that blows air toward the condenser, and the refrigerant downstream of the condenser An evaporator provided on a passage and vaporizing a refrigerant from the condenser;
A control system for controlling the fuel injection valve and the air conditioner system;
The controller is
Controlling the fuel injection amount of the fuel injection valve based on the required torque during vehicle travel,
Determining whether deposits are deposited in the combustion chamber;
When it is determined that the deposit is accumulated, the fuel injection timing of the fuel injection valve is advanced and the refrigerant pressure on the upstream side of the compressor is increased compared to the case where it is not determined that the deposit is accumulated. Performing a first control to reduce the output of the condenser fan so as to increase,
When the demand for increasing the engine resistance applied to the diesel engine is issued, the fuel injection timing of the fuel injection valve is advanced and the upstream side of the compressor is compared with the case where the demand for increasing the engine resistance is not issued. Performing a second control to reduce the output of the condenser fan so that the refrigerant pressure on the side increases.
Performing the first control when the vehicle is being maintained and not running, and performing the second control when the vehicle is running,
A control system for a vehicle, wherein an amount by which the fuel injection timing is advanced in the second control is configured to be smaller than an amount by which the fuel injection timing is advanced in the first control.   The control device is configured to estimate a combustion gas temperature in the combustion chamber, and to reduce a degree to which the output of the condenser fan is reduced as a difference between the combustion gas temperature and a predetermined temperature is smaller. The vehicle control system according to 8 or 9.   The vehicle control system according to any one of claims 7 to 10, wherein the control device is configured to increase a degree of decreasing the output of the condenser fan as the outside air temperature is lower.   12. The control device according to claim 7, wherein the control device is configured to perform control for advancing the fuel injection timing and reducing the output of the condenser fan in a state where the air conditioner system is set to heating. The vehicle control system according to claim 1.

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