JP2018016092A - Hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the occurrence of abnormal sound caused by vibration of a fuel supply device for supplying fuel to a port injection valve and a cylinder injection valve or the like.SOLUTION: An engine is controlled so that a request output is output from the engine. A first pump is controlled so that discharge amount of the first pump becomes larger when the request output is large as compared with a case where the request output is small and so that discharge amount of the first pump becomes larger when a target fuel pressure of fuel supplied to a port injection valve is high as compared with a case where the target fuel pressure is low. When the target fuel pressure is lowered after starting the operation of the engine, the request output is increased as compared with before the target fuel pressure is lowered.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a hybrid vehicle, and more particularly, to a vehicle including an engine, a fuel supply device, a generator, and a battery.

  Conventionally, an automobile including an engine having a port injection valve and an in-cylinder injection valve, and a fuel supply device that supplies fuel to the port injection valve and the in-cylinder injection valve has been proposed (for example, Patent Document 1). reference). Here, the fuel supply device includes a fuel tank, a feed pump that supplies fuel from the fuel tank to the first passage connected to the port injection valve, a check valve provided in the first passage, and a first passage. A high-pressure fuel pump that pressurizes fuel on the port injection valve side of the check valve and supplies the pressurized fuel to the second passage connected to the in-cylinder injection valve. In this automobile, the feed pump is controlled so that the fuel pressure of the fuel supplied to the port injection valve becomes the target fuel pressure.

JP2015-218595A

  In the above-described automobile, when the target fuel pressure of the fuel supplied to the port injection valve is lowered after the engine starts, the feed pump discharge amount is reduced, so that the feed pump side of the first passage is more than the check valve. The check valve may close because the fuel pressure is below the fuel pressure on the port injection valve side. When the check valve is closed, the pulsation of the fuel pressure in the first passage generated by driving the high-pressure fuel pump increases, and the fuel supply device or the like may vibrate and generate abnormal noise.

  The main purpose of the hybrid vehicle of the present invention is to suppress the generation of noise due to vibrations of a fuel supply device that supplies fuel to a port injection valve or an in-cylinder injection valve.

  The hybrid vehicle of the present invention employs the following means in order to achieve the main object described above.

The hybrid vehicle of the present invention
An engine having a port injection valve for injecting fuel into the intake pipe, and an in-cylinder injection valve for injecting fuel into the cylinder;
A fuel tank; a first pump for supplying fuel from the fuel tank to a first passage to which the port injection valve is connected; and a fuel pressure provided in the first passage and on the first pump side A check valve that opens when the fuel pressure is higher than the fuel pressure of the first injection pump and closes when the fuel pressure on the first pump side is equal to or lower than the fuel pressure on the port injection valve side, and more than the check valve in the first passage. A fuel supply device having a second pump for pressurizing the fuel on the port injector side and supplying the fuel to the second passage connected to the cylinder injection valve;
A generator that generates power using power from the engine;
A battery that exchanges power with the generator;
A control device for controlling the engine, the fuel supply device and the generator;
A hybrid vehicle comprising:
The control device controls the engine so that a required output is output from the engine, and when the required output is large, the discharge amount of the first pump is larger than when the required output is small and the port injection valve When the target fuel pressure of the fuel to be supplied to is high, the first pump is controlled so that the discharge amount of the first pump is larger than when the target fuel pressure is low,
Further, when the control device decreases the target fuel pressure after the start of operation of the engine, the control device increases the required output as compared to before reducing the target fuel pressure.
This is the gist.

  In the hybrid vehicle of the present invention, the engine is controlled so that the required output is output from the engine, and when the required output is large, the discharge amount of the first pump is larger than when it is small and supplied to the port injection valve. When the target fuel pressure of the fuel to be used is high, the first pump is controlled so that the discharge amount of the first pump is larger than when the target fuel pressure is low. When the target fuel pressure is reduced after the engine is started, the required output is increased as compared to before the target fuel pressure is reduced. Therefore, a decrease in the discharge amount of the first pump due to the decrease in the target fuel pressure can be suppressed by an increase in the discharge amount of the first pump due to an increase in the required output. Thereby, it can suppress that the fuel pressure by the side of a 1st pump becomes less than the fuel pressure by the side of a port injection valve rather than the check valve in a 1st channel | path, and can suppress that a check valve closes. . As a result, it is possible to suppress an increase in the pulsation of the fuel pressure in the first passage caused by the driving of the second pump, and it is possible to suppress the generation of noise due to the vibration of the fuel supply device.

  In such a hybrid vehicle of the present invention, the control device includes: a first condition in which a storage ratio of the battery is higher than a predetermined ratio when the target fuel pressure is the first predetermined fuel pressure and a predetermined time has elapsed; At least one of the second condition in which the temperature is lower than the first predetermined temperature and the third condition in which the temperature of the battery is higher than the second predetermined temperature higher than the first predetermined temperature can be satisfied. In some cases, the target fuel pressure may be maintained. Here, the “first condition” is a condition for suppressing overcharging due to an increase in charging power of the battery, and the “second condition” is a battery that suppresses an increase in charging power in a low temperature environment of the battery. The “third condition” is a condition for suppressing an excessive increase in temperature of the battery by suppressing an increase in the amount of heat generated due to an increase in charging power of the battery. When the target output is held, the required output (battery charging power) does not need to be increased, so that the battery can be further protected.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. FIG. 2 is a configuration diagram showing an outline of configurations of an engine 22 and a fuel supply device 60. It is a flowchart which shows an example of the target fuel pressure setting routine performed by engine ECU24 of an Example.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention, and FIG. 2 is a configuration diagram showing an outline of the configuration of an engine 22 and a fuel supply device 60.

  As shown in FIG. 1, the hybrid vehicle 20 of the embodiment includes an engine 22, a fuel supply device 60, a planetary gear 30, motors MG1 and MG2, inverters 41 and 42, a battery 50, and a hybrid electronic control unit. (Hereinafter referred to as “HVECU”) 70.

  The engine 22 is configured as an internal combustion engine that outputs power using a fuel such as gasoline or light oil. As shown in FIG. 2, the engine 22 includes a port injection valve 125 that injects fuel into the intake port and an in-cylinder injection valve 126 that injects fuel into the cylinder. The engine 22 includes the port injection valve 125 and the in-cylinder injection valve 126, so that the engine 22 can be operated in any of the port injection mode, the in-cylinder injection mode, and the common injection mode.

  In the port injection mode, air cleaned by the air cleaner 122 is sucked through the throttle valve 124 and fuel is injected from the port injection valve 125 to mix the air and fuel. Then, the air-fuel mixture is sucked into the combustion chamber via the intake valve 128 and is explosively burned by an electric spark by the spark plug 130. The reciprocating motion of the piston 132 pushed down by the energy is converted into the rotational motion of the crankshaft 26. . In the in-cylinder injection mode, air is sucked into the combustion chamber in the same manner as in the port injection mode, fuel is injected from the in-cylinder injection valve 126 during the intake stroke or the compression stroke, and explosive combustion is performed by an electric spark from the spark plug 130. Thus, the rotational movement of the crankshaft 26 is obtained. In the common injection mode, the fuel is injected from the port injection valve 125 when air is sucked into the combustion chamber, and the fuel is injected from the in-cylinder injection valve 126 in the intake stroke or the compression stroke. Thus, the rotational movement of the crankshaft 26 is obtained. These injection modes are switched based on the operating state of the engine 22.

  Exhaust gas from the combustion chamber is discharged to the outside air through a purification device 134 having a purification catalyst (three-way catalyst) that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). Is done.

  As shown in FIG. 2, the fuel supply device 60 is configured as a device that supplies fuel to the port injection valve 125 and the in-cylinder injection valve 126 of the engine 22. The fuel supply device 60 includes a fuel tank 61, a feed pump (first pump) 62 that supplies fuel from the fuel tank 61 to a low-pressure side passage (first passage) 63 to which the port injection valve 125 is connected, and a low-pressure side passage. And a high pressure side passage (second passage) to which the cylinder injection valve 126 is connected by pressurizing fuel on the side of the port injection valve 125 relative to the check valve 64 in the low pressure side passage 63. And a high-pressure fuel pump (second pump) 65 for supplying to 66.

  The feed pump 62 and the check valve 64 are disposed in the fuel tank 61. The feed pump 62 is configured as an electric pump that operates by receiving power supplied from the battery 50. The check valve 64 is opened when the fuel pressure (fuel pressure) on the feed pump 62 side in the low pressure side passage 63 is higher than the pressure on the port injection valve 125 side, and the pressure on the feed pump 62 side is set on the port injection valve 125 side. The valve is closed when the pressure is less than.

  The high-pressure fuel pump 65 is a pump that is driven by power from the engine 22 (rotation of the camshaft) and pressurizes the fuel in the low-pressure side passage 63. The high-pressure fuel pump 65 is connected to the suction port and opens and closes when the fuel is pressurized. The high-pressure fuel pump 65 is connected to the discharge port to prevent the back flow of the fuel and holds the fuel pressure in the high-pressure side passage 66. And a check valve 65b. The high-pressure fuel pump 65 sucks fuel from the feed pump 62 when the electromagnetic valve 65a is opened during operation of the engine 22, and uses the power from the engine 22 when the electromagnetic valve 65a is closed. The fuel supplied to the high pressure side passage 66 is pressurized by intermittently feeding the fuel compressed by the operating plunger (not shown) to the high pressure side passage 66 through the check valve 65b. When the high pressure fuel pump 65 is driven, the fuel pressure in the low pressure side passage 63 and the fuel pressure in the high pressure side passage 66 pulsate according to the rotation of the engine 22 (rotation of the camshaft).

  The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24. Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU, and includes, in addition to the CPU, a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port. .

  Signals from various sensors necessary for controlling the operation of the engine 22 and controlling the fuel supply device 60 are input to the engine ECU 24 via an input port. Examples of signals input to the engine ECU 24 include a crank position θcr from the crank position sensor 140 that detects the rotational position of the crankshaft 26, and a coolant temperature Tw from the coolant temperature sensor 142 that detects the temperature of coolant in the engine 22. Can be mentioned. Another example is the cam position θca from the cam position sensor 144 that detects the rotational position of the intake camshaft that opens and closes the intake valve 128 and the exhaust camshaft that opens and closes the exhaust valve. Further, the throttle opening TH from the throttle valve position sensor 146 for detecting the position of the throttle valve 124, the intake air amount Qa from the air flow meter 148 attached to the intake pipe, and the temperature sensor 149 attached to the intake pipe. The intake air temperature Ta can also be mentioned. In addition, the air-fuel ratio AF from the air-fuel ratio sensor 135a attached to the exhaust pipe and the oxygen signal O2 from the oxygen sensor 135b attached to the exhaust pipe can also be mentioned. Further, the fuel pressure Pfp of the fuel supplied to the port injection valve 125 from the fuel pressure sensor 68 attached in the vicinity of the port injection valve 125 in the low pressure side passage 63 of the fuel supply device 60 and the cylinder in the high pressure side passage 66 of the fuel supply device 60. The fuel pressure Pfd of the fuel supplied to the in-cylinder injection valve 126 from the fuel pressure sensor 69 attached in the vicinity of the inner injection valve 126 can also be mentioned.

  Various control signals for controlling the operation of the engine 22 or controlling the fuel supply device 60 are output from the engine ECU 24 via the output port. Examples of the signal output from the engine ECU 24 include a drive signal to the port injection valve 126, a drive signal to the in-cylinder injection valve 126, a drive signal to the throttle motor 136 that adjusts the position of the throttle valve 124, and an integral with the igniter. A control signal to the ignition coil 138 can be given. Further, a drive control signal to the feed pump 62 and a drive control signal to the electromagnetic valve 65a of the high-pressure fuel pump 65 can be cited.

  The engine ECU 24 is connected to the HVECU 70 via a communication port. The engine ECU 24 calculates the rotational speed Ne of the engine 22 based on the crank angle θcr from the crank position sensor 140. Further, the engine ECU 24 determines the volume efficiency (the volume of air actually sucked in one cycle with respect to the stroke volume per cycle of the engine 22) based on the intake air amount Qa from the air flow meter 148 and the rotational speed Ne of the engine 22. Ratio) KL is calculated.

  As shown in FIG. 1, the planetary gear 30 is configured as a single pinion type planetary gear mechanism. The sun gear of planetary gear 30 is connected to the rotor of motor MG1. The ring gear of the planetary gear 30 is connected to a drive shaft 36 that is coupled to the drive wheels 39a and 39b via a differential gear 38. A crankshaft 26 of the engine 22 is connected to the carrier of the planetary gear 30 via a damper 28.

  The motor MG1 is configured as, for example, a synchronous generator motor, and the rotor is connected to the sun gear of the planetary gear 30 as described above. The motor MG2 is configured as, for example, a synchronous generator motor, and a rotor is connected to the drive shaft 36. Inverters 41 and 42 are connected to motors MG <b> 1 and MG <b> 2 and to battery 50 via power line 54. The motors MG1 and MG2 are driven to rotate by switching control of a plurality of switching elements (not shown) of the inverters 41 and 42 by a motor electronic control unit (hereinafter referred to as “motor ECU”) 40.

  Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . The motor ECU 40 receives signals from various sensors necessary for driving and controlling the motors MG1 and MG2, for example, rotational positions θm1 from rotational position detection sensors 43 and 44 that detect rotational positions of the rotors of the motors MG1 and MG2. , Θm2, and the temperature tm2 of the motor MG2 from the temperature sensor that detects the temperature of the motor MG2 are input via the input port. From the motor ECU 40, switching control signals to a plurality of switching elements (not shown) of the inverters 41 and 42 are output via an output port. The motor ECU 40 is connected to the HVECU 70 via a communication port. The motor ECU 40 calculates the rotational speeds Nm1, Nm2 of the motors MG1, MG2 based on the rotational positions θm1, θm2 of the rotors of the motors MG1, MG2 from the rotational position detection sensors 43, 44.

  The battery 50 is configured as, for example, a lithium ion secondary battery or a nickel hydride secondary battery, and is connected to the inverters 41 and 42 via the power line 54. The battery 50 is managed by a battery electronic control unit (hereinafter referred to as “battery ECU”) 52.

  Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. . Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 via the input port. Examples of signals input to the battery ECU 52 include a battery voltage Vb from a voltage sensor 51 a installed between terminals of the battery 50, a battery current Ib from a current sensor 51 b attached to an output terminal of the battery 50, and a battery 50. The battery temperature Tb from the temperature sensor 51c attached to can be mentioned. The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 calculates the storage ratio SOC based on the integrated value of the battery current Ib from the current sensor 51b. The storage ratio SOC is a ratio of the capacity of power that can be discharged from the battery 50 to the total capacity of the battery 50.

  Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and includes a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port in addition to the CPU. Signals from various sensors are input to the HVECU 70 via input ports. Examples of the signal input to the HVECU 70 include an ignition signal from the ignition switch 80 and a shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81. Further, the accelerator opening Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83, the brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, and the vehicle speed sensor 88 The vehicle speed V can also be mentioned. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port.

  The hybrid vehicle 20 of the embodiment configured in this manner travels in a hybrid travel (HV travel) mode or an electric travel (EV travel) mode. Here, the HV traveling mode is a mode in which the engine 22 is operated while the engine 22 is operated, and the EV traveling mode is a mode in which the engine 22 is not operated.

  In the HV traveling mode, the HVECU 70 first sets the required torque Td * required for the drive shaft 36 based on the accelerator opening Acc and the vehicle speed V, and the rotational speed Nd of the drive shaft 36 is set to the set required torque Td *. To calculate the required power Pd * required for the drive shaft 36. Here, as the rotational speed Nd of the drive shaft 36, for example, the rotational speed Nm2 of the motor MG2 or the rotational speed obtained by multiplying the vehicle speed V by a conversion factor can be used. Subsequently, the required charging power Pch * of the battery 50 is set based on the storage ratio SOC of the battery 50, and the sum of the required power Pd * and the required charging power Pch * is calculated as the required power Pe * required for the vehicle. . Then, the target rotational speed Ne * and the target torque Te * of the engine 22 and the torque command Tm1 of the motors MG1 and MG2 are output so that the required power Pe * is output from the engine 22 and the required torque Td * is output to the drive shaft 36. Set * and Tm2 *. Then, the target rotational speed Ne * and the target torque Te * of the engine 22 are transmitted to the engine ECU 24, and torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the motor ECU 40. When the engine ECU 24 receives the target rotational speed Ne * and the target torque Te * of the engine 22, the engine ECU 24 controls the intake air amount of the engine 22 so that the engine 22 is operated based on the target rotational speed Ne * and the target torque Te *. Fuel injection control, ignition control, etc. are performed. The engine ECU 24 also controls the feed pump 62 and the high-pressure fuel pump 65 of the fuel supply device 60 when operating the engine 22. When motor ECU 40 receives torque commands Tm1 * and Tm2 * of motors MG1 and MG2, switching control of a plurality of switching elements of inverters 41 and 42 is performed such that motors MG1 and MG2 are driven by torque commands Tm1 * and Tm2 *. To do. In this HV travel mode, when the stop condition of the engine 22 is satisfied, such as when the required power Pe * reaches the stop threshold value Pstop or less, the operation of the engine 22 is stopped and the EV travel mode is entered.

  Here, intake air amount control and fuel injection control of the engine 22, and control of the feed pump 62 and the high-pressure fuel pump 65 of the fuel supply device 60 will be described.

  In the intake air amount control, first, the target air amount Qa * is set based on the target torque Te *. Subsequently, the target throttle opening TH * is set so that the intake air amount Qa becomes the target air amount Qa *. Then, the throttle motor 136 is controlled so that the throttle opening TH becomes the target throttle opening TH *.

  In the fuel injection control, first, the execution injection mode is set from the port injection mode, the in-cylinder injection mode, and the common injection mode based on the rotational speed Ne of the engine 22 and the volumetric efficiency KL. Subsequently, based on the target air amount Qa * and the execution injection mode, the target injection amounts of the port injection valve 125 and the in-cylinder injection valve 126 so that the air-fuel ratio AF becomes the target air-fuel ratio AF * (for example, the theoretical air-fuel ratio). Qfp * and Qfd * are set. Then, the target injection times τfp * and τfd * of the port injection valve 125 and the in-cylinder injection valve 126 are set based on the target injection amounts Qfp * and Qfd * and the fuel pressures Pfp and Pfd. When the target injection times τfp * and τpd * are thus set, the in-cylinder injection valve 125 and the port injection valve 126 so that the fuel injection for the target injection times τfp * and τfd * is performed from the in-cylinder injection valve 125 and the port injection valve 126. To control.

  In the control of the feed pump 62, first, the total target injection as the sum of the target fuel pressure Pfp * of the fuel supplied to the port injection valve 125 and the target injection amounts Qfp * and Qfd * of the port injection valve 125 and the in-cylinder injection valve 126. Based on the amount Qfsum, the target discharge amount Qpp * of the feed pump 62 is set. Here, a method for setting the target fuel pressure Pfp * will be described later. Further, in the embodiment, the target discharge amount Qpp * is set so as to increase when the target fuel pressure Pfp * is high compared to when it is low, and to increase when the total target injection amount Qfsum is small. It was. Specifically, the target discharge amount Qpp * is set to increase as the target fuel pressure Pfp * increases and to increase as the total target injection amount Qfpsum increases. When the target discharge amount Qpp * is thus set, the feed pump 62 is controlled so that the discharge amount (fuel amount) from the feed pump 62 becomes the target discharge amount Qpp *.

  In the control of the high-pressure fuel pump 65, first, the target discharge of the high-pressure fuel pump 65 is determined based on the target fuel pressure Pfd * of the fuel supplied to the in-cylinder injection valve 126 and the target injection amount Qfd * of the in-cylinder injection valve 126. Set the quantity Qpd *. Here, as the target fuel pressure Pfd *, for example, about several MPa to several tens of MPa can be used. Further, in the embodiment, the target discharge amount Qpd * is set so as to increase when the target fuel pressure Pfd * is high compared to when it is low and to increase when the target injection amount Qfd * is large compared to when it is small. It was. Specifically, the target discharge amount Qpd * is set to increase as the target fuel pressure Pfd * increases and to increase as the target injection amount Qfd increases. When the target discharge amount Qpd * is thus set, the electromagnetic valve 65a of the high-pressure fuel pump 65 is controlled so that the discharge amount (fuel amount) from the high-pressure fuel pump 65 becomes the target discharge amount Qpd *.

  In the EV travel mode, the HVECU 70 sets the required torque Td * of the drive shaft 36 based on the accelerator opening Acc and the vehicle speed V, sets a value 0 to the torque command Tm1 * of the motor MG1, and sets the required torque Td *. The torque command Tm2 * of the motor MG2 is set, and the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are transmitted to the motor ECU 40. When motor ECU 40 receives torque commands Tm1 * and Tm2 * of motors MG1 and MG2, switching control of a plurality of switching elements of inverters 41 and 42 is performed such that motors MG1 and MG2 are driven by torque commands Tm1 * and Tm2 *. To do. In this EV travel mode, when the start condition of the engine 22 is satisfied, such as when the required power Pe * calculated in the same manner as in the HV travel mode reaches a start threshold Pstart greater than the stop threshold Pstop, the engine 22 22 is started to shift to the HV traveling mode.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the processing when setting the target fuel pressure Pfp * of the fuel supplied to the port injection valve 125 will be described. FIG. 3 is a flowchart illustrating an example of a target fuel pressure setting routine executed by the engine ECU 24 of the embodiment. This routine is executed when the operation of the engine 22 is started.

  When the target fuel pressure setting routine is executed, the engine ECU 24 first sets a relatively high predetermined fuel pressure Pfpup to the target fuel pressure Pfp * (step S100). Here, for example, 510 kPa, 530 kPa, 550 kPa, or the like can be used as the predetermined fuel pressure Pfpup. In this way, by setting the target fuel pressure Pfp * to a relatively high predetermined fuel pressure Pfpup, fuel atomization is promoted as compared with the case where the target fuel pressure Pfp * is set to a relatively low predetermined fuel pressure Pfpno described later. Can do.

  When the predetermined fuel pressure Pfpup is set to the target fuel pressure Pfp * in this way, it waits for the predetermined time T1 to elapse (step S110). Here, for example, 5 seconds, 6 seconds, 7 seconds, or the like can be used as the predetermined time T1. And when predetermined time T1 passes, the electrical storage ratio SOC and battery temperature Tb of the battery 50 are input (step S120). Here, the storage ratio SOC of the battery 50 is calculated based on the integrated value of the battery current Ib from the current sensor 51b and is input from the battery ECU 52 via the HVECU 70 by communication. The battery temperature Tb of the battery 50 is input from the battery ECU 52 via the HVECU 70 by communication, as detected by the temperature sensor 51c.

  Next, the power storage ratio SOC of the battery 50 is compared with the threshold value Sref (step S130), and it is determined whether or not the battery temperature Tb of the battery 50 is not less than the threshold value Tblo and not more than the threshold value Tbhi (step S140). Here, for example, 70%, 75%, 80%, or the like can be used as the threshold value Sref. For example, −20 ° C., −15 ° C., −10 ° C., or the like can be used as the threshold value Tblo, and the threshold value Tbhi can be used. For example, 45 ° C., 50 ° C., 55 ° C., or the like can be used. Details of the threshold value Sref, the threshold value Tblo, and the threshold value Tbhi will be described later.

  In steps S130 and S140, when the storage ratio SOC of the battery 50 is equal to or lower than the threshold value Sref and the battery temperature Tb of the battery 50 is equal to or higher than the threshold value Tblo and equal to or lower than the threshold value Tbhi, a charge power increase command is transmitted to the HVECU 70 ( In step S150), the target fuel pressure Pfp * is switched from the predetermined fuel pressure Pfpup to a predetermined fuel pressure Pfpno lower than that (step S160), and this routine is terminated. Here, for example, 380 kPa, 400 kPa, 420 kPa, or the like can be used as the predetermined fuel pressure Pfpno. When this routine is completed, the target fuel pressure Pfp * is maintained at the predetermined fuel pressure Pfpno. When receiving the charge power increase command, the HVECU 70 adds a value (Pchtmp + α) obtained by adding a positive predetermined value α (for example, about several kW) to the basic value Pchtmp based on the storage ratio SOC of the battery 50 for a predetermined time T2. Set as charge request power Pch *. Note that the basic value Pchtmp is set to the charge request power Pch * when the charge power increase command is not received or after a predetermined time T2 has elapsed since the charge power increase command was received. Therefore, after the HVECU 70 receives the charge power increase command (after the target fuel pressure Pfp * is switched from the predetermined fuel pressure Pfpup to the predetermined fuel pressure Pfpno), the charge request power Pch is longer than the other times during the predetermined time T2. * Charging power increase processing to increase * is performed.

  Consider a case where the target fuel pressure Pfp * is switched (decreased) from the predetermined fuel pressure Pfpup to the predetermined fuel pressure Pfpno. When the target fuel pressure Pfp * is decreased, the discharge amount of the feed pump 62 is reduced. Therefore, the pressure on the feed pump 62 side of the low pressure side passage 63 becomes lower than the pressure on the port injection valve 125 side, and the reverse is reversed. The stop valve 64 may close. When the check valve 64 is closed, the pulsation of the fuel pressure in the low-pressure side passage 63 generated by driving the high-pressure fuel pump 65 increases, and the fuel supply device 60 (low-pressure side passage 63, fuel tank 61, etc.) or the fuel supply device 60 The vibration of the vehicle body where the vehicle is placed becomes large, and abnormal noise may occur. In the embodiment, when the target fuel pressure Pfp * is decreased, the required charging power Pch * is increased. Therefore, the required power Pe * and the target torque Te * are increased, and the total target injection of the port injection valve 125 and the in-cylinder injection valve 126 is increased. The quantity Qfsum (= Qfp * + Qfd *) can be increased. As a result, it is possible to suppress the discharge amount of the feed pump 62 from being reduced, so that the pressure on the feed pump 62 side becomes lower than the pressure on the port injection valve 125 side with respect to the check valve 64 in the low pressure side passage 63. Therefore, the check valve 64 can be prevented from closing. As a result, it is possible to suppress the pulsation of the fuel pressure in the low-pressure side passage 63 generated by driving the high-pressure fuel pump 65, and the fuel supply device 60 (the low-pressure side passage 63, the fuel tank 61, etc.), the vehicle body, etc. Generation of abnormal noise due to vibration can be suppressed.

  The predetermined value α is preferably set so that the check valve 64 can be prevented from closing. Further, the above-described threshold value Sref is a threshold value used to determine whether or not there is a possibility of overcharging when the charging power increase process is performed. The threshold value Tblo is a threshold value that is used to determine whether or not the battery 50 is in a low temperature environment when the charging power increase process is performed, so that the deterioration of the battery 50 may be accelerated. The threshold value Tbhi is a threshold value used to determine whether or not there is a possibility that an excessive temperature rise of the battery 50 will occur due to an increase in the amount of heat generated when the charging power increase process is performed.

  When the power storage ratio SOC of the battery 50 is larger than the threshold value Sref in step S130, or when the battery temperature Tb of the battery 50 is lower than the threshold value Tblo or higher than the threshold value Tbhi in step S140, the processes of steps S150 and S160 are executed. That is, the target fuel pressure Pfp * is held at the predetermined fuel pressure Pfpup, and this routine is terminated. As a result, overcharging due to an increase in charging power of the battery 50 is suppressed, deterioration of the battery 50 is suppressed by suppressing an increase in charging power in the low temperature environment of the battery 50, or due to an increase in charging power of the battery 50 An increase in the amount of heat generation can be suppressed, and an excessive temperature rise of the battery 50 can be suppressed. In this case, the target fuel pressure Pfp * is predetermined when the storage ratio SOC of the battery 50 is equal to or lower than the threshold value Sref and the battery temperature Tb of the battery 50 is equal to or higher than the threshold value Tblo and equal to or lower than the threshold value Tbhi. It is good also as what switches to fuel pressure Pfpno.

  In the hybrid vehicle 20 of the embodiment described above, when the target fuel pressure Pfp * is set to the target fuel pressure Pfp * at the start of operation of the engine 22 and the target fuel pressure Pfp * is switched to the predetermined fuel pressure Pfpno lower than the predetermined fuel pressure Pfpup, Compared to the previous case, the required power Pe * of the engine 22 and thus the target torque Te * are increased by increasing the required charging power Pch *, and the total target injection amount Qfsum of the port injection valve 125 and the in-cylinder injection valve 126 is increased. To do. As a result, when the target fuel pressure Pfp * is lowered, the discharge amount of the feed pump 62 can be prevented from being lowered, and the pressure on the feed pump 62 side is higher than the check valve 64 in the low pressure side passage 63. It is possible to suppress the pressure from becoming lower than the pressure on the 125 side, and it is possible to suppress the check valve 64 from closing. As a result, it is possible to suppress the pulsation of the fuel pressure in the low-pressure side passage 63 generated by driving the high-pressure fuel pump 65, and the fuel supply device 60 (the low-pressure side passage 63, the fuel tank 61, etc.), the vehicle body, etc. Generation of abnormal noise due to vibration can be suppressed.

  In the hybrid vehicle 20 of the embodiment, when the predetermined fuel pressure Pfpup is set to the target fuel pressure Pfp * and the predetermined time T1 has elapsed, the target fuel pressure Pfp * is set to the predetermined fuel pressure Pfpno according to the storage ratio SOC of the battery 50 and the battery temperature Tb. It was determined whether to switch or hold at a predetermined fuel pressure Pfpup. However, when the predetermined fuel pressure Pfpup is set to the target fuel pressure Pfp * and the predetermined time T1 has elapsed, the target fuel pressure Pfp * is set to the predetermined fuel pressure Pfpno according to only one of the storage ratio SOC of the battery 50 and the battery temperature Tb. It is good also as what judges whether it changes to or hold | maintains with predetermined fuel pressure Pfpup. Further, when the predetermined fuel pressure Pfpup is set to the target fuel pressure Pfp * and the predetermined time T1 has elapsed, the target fuel pressure Pfp * may be switched to the predetermined fuel pressure Pfpno regardless of the storage ratio SOC of the battery 50 or the battery temperature Tb. Good. When the target fuel pressure Pfp * is switched, the same effect as in the embodiment can be obtained by increasing the required power Pe * by increasing the required charging power Pch * by performing the charging power increasing process. it can.

  In the hybrid vehicle 20 of the embodiment, the engine ECU 24, the motor ECU 40, and the HVECU 70 are provided. However, the engine ECU 24, the motor ECU 40, and the HVECU 70 may be configured as a single electronic control unit.

  In the embodiment, the engine 22 and the motor MG1 are connected to the drive shaft 36 connected to the drive wheels 39a and 39b via the planetary gear 30, and the motor MG2 is connected to the drive shaft 36. However, a configuration of a so-called one-motor hybrid vehicle in which a motor is connected to a drive shaft connected to a drive wheel via a transmission and an engine is connected to a rotation shaft of the motor via a clutch. Alternatively, a so-called series hybrid vehicle may be configured in which a travel motor is connected to a drive shaft coupled to a drive wheel and a power generation motor that exchanges electric power with the travel motor is connected to an output shaft of the engine.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to the “engine”, the motor MG1 corresponds to the “generator”, the battery 50 corresponds to the “battery”, the fuel supply device 60 corresponds to the “fuel supply device”, the engine The ECU 24, the motor ECU 40, and the HVECU 70 correspond to a “control device”.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. Therefore, the elements of the invention described in the column of means for solving the problems are not limited. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of hybrid vehicles.

  20 hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 28 damper, 30 planetary gear, 36 drive shaft, 38 differential gear, 39a, 39b drive wheel, 40 electronic control unit for motor (motor) ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51a voltage sensor, 51b current sensor, 51c temperature sensor, 52 battery electronic control unit (battery ECU), 54 power line, 60 fuel supply device , 61 Fuel tank, 62 Feed pump, 63 Low pressure side passage, 64 Check valve, 65 High pressure fuel pump, 65a Solenoid valve, 65b Check valve, 66 High pressure side passage, 68, 69 Fuel pressure sensor, 70 Hybrid Electronic control unit (HV ECU), 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 122 air cleaner, 124 throttle Valve, 125 port injection valve, 126 In-cylinder injection valve, 128 Intake valve, 130 Spark plug, 132 Piston, 134 Purifier, 135a Air-fuel ratio sensor, 135b Oxygen sensor, 136 Throttle motor, 138 Ignition coil, 140 Crank position sensor, 142 water temperature sensor, 144 cam position sensor, 146 throttle valve position sensor, 148 air flow meter, 149 temperature Sensor, MG1, MG2 motor.

Claims (1)

An engine having a port injection valve for injecting fuel into the intake pipe, and an in-cylinder injection valve for injecting fuel into the cylinder;
A fuel tank; a first pump for supplying fuel from the fuel tank to a first passage to which the port injection valve is connected; and a fuel pressure provided in the first passage and on the first pump side A check valve that opens when the fuel pressure is higher than the fuel pressure of the first injection pump and closes when the fuel pressure on the first pump side is equal to or lower than the fuel pressure on the port injection valve side, and more than the check valve in the first passage. A fuel supply device having a second pump for pressurizing the fuel on the port injector side and supplying the fuel to the second passage connected to the cylinder injection valve;
A generator that generates power using power from the engine;
A battery that exchanges power with the generator;
A control device for controlling the engine, the fuel supply device and the generator;
A hybrid vehicle comprising:
The control device controls the engine so that a required output is output from the engine, and when the required output is large, the discharge amount of the first pump is larger than when the required output is small and the port injection valve When the target fuel pressure of the fuel to be supplied to is high, the first pump is controlled so that the discharge amount of the first pump is larger than when the target fuel pressure is low,
Further, when the control device decreases the target fuel pressure after the start of operation of the engine, the control device increases the required output as compared to before reducing the target fuel pressure.
Hybrid car.

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