JP2009228445A - Fuel feeding method and fuel feeding device for engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reliably prevent abnormal combustion or misfire when the fuel feed pressure is too low. <P>SOLUTION: A fuel in a fuel tank 43 is fed to fuel injection valves 11, 12 of an engine EG. When the pressure in the fuel tank 43 is higher than the predetermined value, the fuel is injected at least from the fuel injection valve 12 for executing the direct fuel injection into a cylinder. When the pressure in the fuel tank 43 is lower than the predetermined pressure, the fuel is injected only from the fuel injection valve 11 for injecting the fuel into an intake passage. When the pressure in the fuel tank 43 is smaller than the predetermined value, the minimum fuel injection from the first fuel injection valve 11 is corrected to increase. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fuel supply method and supply device for an engine.

In an engine using gaseous fuel as fuel, as shown in Patent Document 1, a port injection unit that injects fuel into an intake passage and a direct injection unit that directly injects fuel into a cylinder are provided as fuel injection units. There is something to prepare. Further, in Patent Document 2, in an engine using gasoline as a fuel, a port injection unit and a direct injection unit are provided, and when the pressure of fuel supplied to the injection unit becomes low, fuel injection by the direct injection unit is performed. There is disclosed an apparatus in which the state is switched from fuel injection by the port injection means.
JP 2007-303403 A Japanese Patent Laid-Open No. 4-132876

  By the way, if the supply pressure of the fuel to the injection means decreases, mixing is not performed well, causing abnormal combustion and misfire, and some measures are desired in this respect. In particular, in the case of gaseous fuel, since it is common to supply gaseous fuel to the injection means using the pressure in the fuel tank that stores the high-pressure gaseous fuel, when the pressure in the fuel tank decreases, The supply pressure of the gaseous fuel supplied to the injection means must be reduced.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an engine fuel supply method in which abnormal combustion or misfire does not occur even when the fuel supply pressure to the injection means decreases, and It is to provide a supply device.

In order to achieve the above object, the following first solution is adopted in the fuel supply method of the present invention. That is, as described in claim 1 in the claims,
An engine fuel supply method comprising a port injection means for supplying fuel to an intake passage of an engine as a fuel supply means,
When the supply pressure of the fuel to the port injection means is lower than a predetermined pressure, the minimum fuel amount supplied to the engine is increased and corrected as compared with the case where the pressure is higher than the predetermined pressure;
It is like that. According to the above solution, since the minimum fuel amount is corrected to increase, stable combustion is ensured, and abnormal combustion and misfire can be reliably prevented.

A preferred mode based on the first solution is as set forth in claims 2 and 3 in the claims. That is,
The fuel is a gaseous fuel,
The fuel supply means further includes a direct injection means for directly injecting fuel into the cylinder of the engine,
When the fuel supply pressure to each of the injection means is equal to or higher than the predetermined pressure, at least a part of the fuel is supplied from the direct injection means, while when the fuel supply pressure to each of the injection means falls below the predetermined pressure , Supplying fuel only from the port injection means,
(Corresponding to claim 2). In this case, in order to directly inject gaseous fuel into the cylinder against the high pressure in the cylinder, a fuel supply pressure higher than a certain level is required. From this point of view, when the fuel supply pressure is high, at least a part of the gaseous fuel is directly injected into the cylinder so as to obtain the advantages of direct injection such as improvement of fuel consumption and ensuring responsiveness of fuel supply, When the fuel supply pressure is low, the fuel can be reliably supplied by injecting gaseous fuel into the intake passage.

A vehicle receives at least one of an engine, a generator driven by the engine, a power storage device that receives power generated from the power generator, and power that is generated from the power generator and power that is discharged from the power storage device. With a motor for driving the vehicle,
A first operating region in which the vehicle is driven to travel by the motor without driving the engine, and a second operating region in which the required output is set larger than the first operating region to drive the vehicle while driving the engine are set. And
In the second operating region, when the fuel supply pressure falls below the predetermined pressure, the minimum fuel amount supplied to the engine is corrected to be increased and the first operating region is expanded.
(Corresponding to claim 3). In this case, when the vehicle is driven by a motor, when the required output is small, the engine is stopped and driven by the motor (first operation region), while the engine is driven when the required output is large. By doing so, it is possible to generate electricity and to ensure a large amount of power supplied to the motor (second operation region). Further, in the second operation region, while preventing abnormal combustion and misfiring by reliably increasing the minimum fuel amount, expanding the first operation region along with this increase correction makes it possible to perform appropriate operation according to the increase correction. The area can be set.

In order to achieve the above object, the following second solution is adopted in the fuel supply device of the present invention. That is, as described in claim 4 in the claims,
Port injection means for supplying fuel to the intake passage of the engine;
Supply pressure detection means for detecting the supply pressure of fuel to the port injection means;
A controller that receives the output from the supply pressure detection means and controls the port injection means;
With
The controller increases and corrects the minimum amount of fuel supplied from the port injection means to the engine when the supply pressure detected by the supply pressure detection means falls below a predetermined pressure, compared to when the supply pressure is higher than the predetermined pressure. ,
It is like that. According to the above solution, a fuel supply apparatus for executing the fuel supply method of claim 1 is provided.

Preferred embodiments based on the second solution are as described in claims 5 and 6 in the claims. That is,
The fuel is a gaseous fuel,
Direct injection means for directly injecting fuel into the cylinder of the engine;
The controller is set to control the port injection means and the direct injection means;
The controller supplies at least part of the fuel from the direct injection means when the supply pressure detected by the supply pressure detection means is equal to or higher than the predetermined pressure, while the supply pressure detected by the supply pressure detection means When the pressure falls below the predetermined pressure, fuel is supplied only from the port injection means.
(Corresponding to claim 5). In this case, a fuel supply apparatus for executing the fuel supply method of claim 5 is provided.

A vehicle receives at least one of an engine, a generator driven by the engine, a power storage device that receives power generated from the power generator, and power that is generated from the power generator and power that is discharged from the power storage device. With a motor for driving the vehicle,
The controller includes a first operation region in which the vehicle is driven to travel by the motor without driving the engine, and a second operation in which the vehicle is driven to travel while driving the engine with a required output larger than the first operation region. Area and remember
When the fuel supply pressure detected by the supply pressure detection means falls below the predetermined pressure in the second operation region, the controller corrects the minimum amount of fuel to be supplied to the engine and corrects the increase in the first operation region. To enlarge the
(Corresponding to claim 6). In this case, a fuel supply apparatus for executing the fuel supply method of claim 3 is provided.

  According to the present invention, it is possible to reliably prevent abnormal combustion and misfire when the fuel supply pressure to the injection means decreases.

  In FIG. 1, EG is an engine, which is a Wankel type rotary piston engine having two cylinders of a first cylinder E1 and a second cylinder E2. The supply of intake air to each of the cylinders E1 and E2 is performed from the common intake passage 1 through the branch intake passage 2. The fuel is supplied to the cylinders E1 and E2 from the first and second fuel injection valves 11 and 12, respectively. The fuel injection valves 11 and 12 each inject hydrogen as gaseous fuel, as will be described later. The first fuel injection valve 11 performs fuel injection into the branch intake passage 2. Further, the second fuel injection valve 12 performs fuel injection directly into the cylinder. An exhaust gas purification catalyst 21 is connected to the exhaust passage 20 of the engine EG. In FIG. 1, 13 is a throttle valve, 14 is a spark plug, 15 is a rotor, and 16 is a rotor housing.

  FIG. 2 shows an example of a fuel supply path to the fuel injection valves 11 and 12. In FIG. 2, reference numeral 40 denotes a common path to which the fuel injection valves 11 and 12 are connected. The common path 40 is connected to the fuel tank 43 via the first path 41. The fuel tank 43 stores hydrogen as a gaseous fuel, and the maximum pressure during storage is, for example, 35 MPa. An electromagnetic first cutoff valve 45 is connected to the first path 41, and a pressure reducing valve 50 is connected downstream of the first cutoff valve 45. As will be described later, the pressure reducing valve 50 reduces the high-pressure hydrogen in the fuel tank 43 to a predetermined pressure (for example, 0.6 PMa) and supplies it to the common path 40 (that is, the fuel injection valves 11 and 12). It has become. When the pressure from the fuel tank 43 side becomes smaller than the predetermined pressure, the pressure reducing valve 50 is substantially cut off and cannot supply hydrogen to the fuel injection valves 11 and 12. .

  A second path 42 is connected to the first path 41 in the form of a bypass passage that bypasses the pressure reducing valve 50. That is, the second path 42 as a bypass passage has one end connected to the first path 41 between the first shutoff valve 45 and the pressure reducing valve 50, and the other end connected to the pressure reducing valve 50 and the common path 40. Are connected to the first path 41. An electromagnetic second shut-off valve 46 is connected to the second path 42.

  FIG. 3 shows an example of the pressure reducing valve 50. In FIG. 3, reference numeral 51 denotes a housing, and a primary side chamber 52 and a secondary side chamber 53 are formed in the housing 51. The primary side chamber 52 is supplied with hydrogen in the fuel tank 43 from an inlet 54 formed in the housing 51, and the inlet 54 serves as a connection port to the fuel tank 43 side. The secondary side chamber 53 discharges hydrogen from an outlet 55 formed in the housing 51, and this outlet 55 serves as a connection port to the common path 40 (that is, the fuel injection valves 11 and 12). ing.

  The primary side chamber 52 and the secondary side chamber 53 communicate with each other via a communication port 56, and the opening degree of the communication port 56 is adjusted by a valve body 57. The valve body 57 is fixed to a diaphragm 59 disposed above the secondary side chamber 53 via a valve shaft 58. The diaphragm 59 is urged downward by a spring 60. The pressure of the secondary side chamber 53 is applied to the lower surface of the diaphragm 59 via the communication port 61. The upper space of the diaphragm 59 is communicated with the atmosphere via the atmosphere release port 62. In FIG. 5, reference numeral 63 denotes a heat radiating fin integrated with the housing 51.

  The pressure regulation operation by the pressure reducing valve 50 is performed as follows. That is, the same pressure as that in the fuel tank 43 is applied to the primary side chamber 52 on the assumption that the first shutoff valve 45 is opened. Now, if the pressure in the secondary side chamber 53 is smaller than a predetermined pressure (0.6 PMa in the embodiment), the diaphragm 59 is displaced downward by the urging force of the spring 60, and the valve element 57 moves through the communication port 56. open. By opening the communication port 56, the hydrogen in the primary side chamber 52 flows into the secondary side chamber 53. When the pressure in the secondary side chamber 53 becomes larger than the predetermined pressure, the diaphragm 59 is displaced upward against the urging force of the spring 60, and the valve body 57 closes the communication port 56, and the secondary side chamber 53. Is prevented from becoming higher than a predetermined pressure. In this manner, the pressure in the secondary side chamber 53 is maintained at a predetermined pressure while the diaphragm 59, that is, the valve body 57 is displaced up and down. However, when the pressure in the primary side chamber 52 (pressure in the fuel tank 43) becomes lower than the predetermined pressure, the valve body 57 remains closed at the communication port 56, and therefore, the supply of hydrogen to the secondary side chamber 53 is prevented. Will be blocked.

  FIG. 4 shows an example when the engine EG is mounted on a vehicle. The automobile VC as a vehicle has an AC motor 71. The AC motor 71 drives the left and right front wheels 73FR and 73FL via the differential gear 72. The left and right rear wheels 73RR and 73RL are driven wheels.

Reference numeral 80 denotes a high voltage battery as a power storage device. A direct current from the high voltage battery 80 is converted into an alternating current by a DC-AC converter 81 including an inverter as a converter, and the converted alternating current is converted into an alternating current. Supplied to AC motor 71. Reference numeral 83 denotes an AC generator driven by the engine EG. The electric power generated by the generator 83 is supplied to the high voltage battery 80 via the AC-DC converter 84 formed of an inverter, and is also supplied to the AC motor 71 via the DC-AC converter 81. It has become. In addition,
A low voltage battery (not shown) (for example, a 12V battery) is also charged via the DC-AC converter 81, and the starter motor 93 (see FIG. 5) of the engine EG, fuel, and the like are charged by the low voltage battery. In addition to the injection valves 11 and 12 and the spark plug 14, power is supplied to various lamps and the like.

  FIG. 5 is a block diagram showing the control system of the present invention. In the figure, U is a controller (control unit) configured using a microcomputer. Signals from the sensors 31 to 35 are input to the controller U. The sensor 31 detects the intake air amount. The sensor 32 detects the opening degree of the throttle valve. The sensor 33 detects the vehicle speed. The sensor 34 detects the engine speed. The sensor 35 detects the pressure in the fuel tank 43 and constitutes supply pressure detection means. On the other hand, the controller U controls the fuel injection valves 11 and 12, the spark plug 14, and the shut-off valves 45 and 46, the AC motor 71, the generator 83, the starter motor 93 for starting the engine EG, and the shut-off valves. 45, 46, DC-AC converter 81 and the like are controlled.

  Next, the control contents of the controller U will be described focusing on the supply of hydrogen to the fuel injection valves 11 and 12, the operation of the fuel injection valves 11 and 12, and the operation of the engine EG. The first shut-off valve 45 is opened when the ignition switch is ON, and is closed when the ignition switch is OFF. The first shut-off valve 45 is opened. I will explain it on the premise. First, the controller U basically closes the second shut-off valve 46 when the pressure in the fuel tank 43 is higher than a predetermined pressure, and the hydrogen in the fuel tank 43 is connected to the first pressure valve 50 connected to the pressure reducing valve 50. It is supplied only through the first path 41 (there is no hydrogen supply from the second path 42). Thus, the hydrogen after being regulated to a predetermined pressure is supplied to the fuel injection valves 11 and 12 by the action of the pressure reducing valve 50. Further, when the pressure in the fuel tank 43 becomes smaller than the predetermined pressure, the controller U opens the second shutoff valve 46. As a result, hydrogen is supplied to the fuel injection valves 11 and 12 only from the second path 42 (as described above, when the pressure in the fuel tank 43 is lower than the predetermined pressure, the pressure reducing valve 50 is closed).

  The predetermined pressure (0.6 PMa in the embodiment) set by the pressure reducing valve 50 is set as the lowest pressure at which fuel can be directly injected into the cylinder. That is, in order to inject hydrogen against the pressure in the cylinder, a pressure of a certain level or more is required as the pressure of hydrogen supplied to the fuel injection valves 11 and 12. Therefore, the fuel injection mode is changed depending on whether the pressure of hydrogen supplied to the fuel injection valves 11 and 12 is a predetermined pressure or smaller than the predetermined pressure. That is, when hydrogen at a predetermined pressure can be supplied to the fuel injection valves 11 and 12 (when hydrogen is supplied from the first path 41), both of the engine rotation speeds are higher than the predetermined rotation speed. While hydrogen is injected from the fuel injection valves 11 and 12 (improvement of mixing performance), when it is lower than the predetermined rotational speed, hydrogen is injected only from the second fuel injection valve 12.

  On the other hand, when the pressure in the fuel tank 43 is lower than a predetermined pressure (when hydrogen is supplied via the second path 42), hydrogen is injected only from the first fuel injection valve 11 (so-called port injection). . This is because the in-cylinder injection cannot be performed or becomes insufficient when the pressure of the supplied hydrogen is lower than a predetermined pressure. Further, when the pressure in the fuel tank 43 is smaller than the predetermined pressure, the minimum fuel injection amount from the second fuel injection valve 12 is corrected to be increased. As a result, when the fuel supply pressure is low, abnormal combustion and misfire are reliably prevented.

  FIG. 9 shows how the minimum fuel injection amount is increased and corrected in the case of port injection in which fuel is injected only from the first fuel injection valve 11 when the fuel supply pressure is smaller than the predetermined pressure. That is, in FIG. 9, when the pressure in the fuel tank 43 is equal to or higher than a predetermined pressure, fuel is injected in the stroke shown in FIG. 9F1. More specifically, fuel injection is started at the timing e2 when the intake pressure becomes negative pressure, and the fuel injection is finished at timing e1 when the intake pressure rises to near the positive pressure. On the other hand, when the pressure in the fuel tank 43 becomes smaller than the predetermined pressure, the fuel injection is executed within the range shown in FIG. 9F2, and the end timing of the fuel injection is when the pressure in the fuel tank 43 is equal to or higher than the predetermined pressure. The fuel injection start timing e4 is set earlier than when the pressure in the fuel tank 43 is equal to or higher than a predetermined pressure. Note that, in the fuel injection range of F2, the range from e4 to e3 is a substantial increase correction amount, and the range from e3 to e2 is in terms of control for compensating that the fuel supply pressure has decreased. (The absolute increase in fuel injection amount is the same as the minimum injection amount when the fuel supply pressure is large by executing fuel injection in the range from e3 to e1 with apparent increase correction) .

  The controller U stores a map in which an operation region as shown in FIG. 6 is set. This map is set with the accelerator opening (same as the throttle opening at the engine load) and the vehicle speed as parameters, and is divided into three operating regions by the α1 line and the β line. An operation region having a small required torque limited by the α1 line is defined as a first operation region. Further, a range surrounded by the α1 line and the β line is a second operation region in which the required torque is larger than that in the first operation region. Further, the range of the required torque that is larger than the β line is set as the third operation region.

  In the first operation region, the engine EG is stopped and the AC motor 71 is driven only by the electric power from the high voltage battery 80. In the second operation region, the engine EG is driven, and the AC motor 1 is driven only by the generated power from the generator 83 (the high voltage battery 80 does not supply power to the AC motor 1). In the third operation region, the engine EG is operated, and the AC motor 71 is driven by receiving both the generated power from the generator 83 and the power from the high voltage battery 80.

  In the second operation region where the engine EG is driven, the minimum fuel injection amount is corrected to be increased. That is, in FIG. 8, the minimum injection amount when the fuel supply pressure is high is indicated by δ1, the minimum injection amount when the fuel supply pressure is low is indicated by δ2, and δ1 <δ2. With the increase correction of the minimum injection amount, the α1 line that becomes the boundary line between the setting of the operation region, in particular, the first operation region where the engine EG is stopped and the second operation region where the engine EG is driven is shown in FIG. As shown, the torque is corrected in the direction of increasing torque as compared with the case of FIG. 6 (the first operation region is corrected to be enlarged).

  Note that, even in the first operating region, the engine EG is driven to a high level when the charged amount (charge amount) of the high voltage battery 80 becomes equal to or less than a first predetermined value (for example, 30% of the full charge amount). The voltage battery 80 is charged, and this charging is stopped when the charge amount of the high voltage battery 80 reaches a second predetermined value (for example, 80% of the full charge amount of the high voltage battery 80).

  The details of the control performed by the controller U will be described with reference to the flowcharts shown in FIGS. In the following description, S indicates a step, and it is assumed that the ignition switch is turned on and the first shut-off valve 45 is opened. Further, the controller U controls the selection of the fuel injection valve to be injected (FIG. 10), the map selection control shown in FIGS. 6 and 7 (FIG. 11), and the change of the power supply mode to the AC motor 71. Control (FIG. 12) is sequentially performed.

  Based on the above, first, the pressure in the fuel tank 43 detected by the sensor 35 is read in S1 of FIG. Next, it is determined whether or not the pressure read in S1 is lower than 0.6 PMa as a predetermined pressure. When the determination in S2 is NO, in S3, the second shutoff valve 46 is closed. Thereafter, in S4, it is determined whether or not the engine speed detected by the sensor 34 is a high speed at which the engine speed is equal to or higher than a predetermined speed. When the determination in S4 is YES, in S5, fuel injection is executed from both fuel injection valves 11 and 12 (port injection + in-cylinder injection). Further, when the determination in S4 is NO, in S6, fuel injection is executed only from the second fuel injection valve 12 (in-cylinder injection). If the determination in S2 is YES, the second shutoff valve 46 is opened in S7. Thereafter, in S8, fuel injection is executed only from the first fuel injection valve 11 (port injection), and the minimum injection amount is increased (increase correction control is executed during fuel injection from the fuel injection valve 12). )

  After the control in FIG. 10 is completed, the control in FIG. 11 is executed. First, in S11, the pressure in the fuel tank 43 detected by the sensor 35 is read. Next, in S12, it is determined whether or not the read pressure in the fuel tank 43 is lower than 0.6 PMa as a predetermined pressure. When the determination in S12 is NO, in S13, the map A when the fuel pressure is large as shown in FIG. 6 is selected as the map used for control. When the determination in S12 is YES, the map B when the fuel pressure is low as shown in FIG. 7 is selected, and a process for increasing the minimum injection amount is corrected.

  After the control of FIG. 11 is completed, the control of FIG. 12 is executed. First, in S21, the vehicle speed, the accelerator opening degree, and the charge amount of the high voltage battery 80 are read. Thereafter, in S22, the accelerator opening (throttle opening) and the vehicle speed are collated with the map selected by the control of FIG. 11, and the required torque is set to the first threshold value (α1 line of FIG. 6 or FIG. 7). It is determined whether or not (α2 line) has been exceeded, that is, whether or not the range of the first operating region has been exceeded. When the determination in S22 is NO, since this is the first operation region, the AC motor 71 is driven by receiving power only from the high voltage battery 80 in S23. If the determination in S22 is YES, it is determined in S24 whether or not the required torque exceeds the second threshold value (β line in FIGS. 6 and 7). When the determination in S24 is NO, since this is the second operation region, in S25, the engine EG is driven to generate power by the generator 83, and the AC motor 71 is driven only by the power generated by the generator 83. To do. When the determination in S24 is YES, it is in the third operating region. In this case, in S26, the AC motor 71 causes both the power generated by the generator 83 and the discharged power from the high voltage battery 80 to be both. Driven by.

  Although the embodiment has been described above, the present invention is not limited to the embodiment, and can be appropriately changed within the scope described in the claims, and includes, for example, the following cases. . The engine may be a reciprocating type, and can also be applied to a vehicle that is not a hybrid vehicle. When applied to a hybrid vehicle, the output of the engine EG may be used for driving the vehicle. The gaseous fuel is not limited to hydrogen, and can be selected from appropriate fuels such as natural gas and propane gas. The fuel is not limited to gaseous fuel, and may be liquid fuel such as gasoline, light oil, bioethanol and the like. Each step or group of steps shown in the flowchart can be expressed as a means for realizing the function. Of course, the object of the present invention is not limited to what is explicitly stated, but also implicitly includes providing what is substantially preferred or expressed as an advantage.

1 is an overall system diagram illustrating an example of an engine to which the present invention is applied. The figure which shows an example of a fuel system | strain. Sectional drawing which shows an example of a pressure-reduction valve. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a simplified system diagram illustrating an example of a vehicle that is driven by a motor. The figure which shows the example of a control system of this invention in a block diagram. The figure which shows the example of a setting of an operation area | region when fuel supply pressure is high. The figure which shows the example of a setting of an operation area | region when fuel supply pressure is low. The figure which shows the increase correction of the minimum fuel injection amount. The figure which shows the aspect of the fuel injection for ensuring the minimum fuel injection quantity in contrast with the time when the fuel supply pressure is high and low. The flowchart which shows the example of control of this invention. The flowchart which shows the example of control of this invention. The flowchart which shows the example of control of this invention.

Explanation of symbols

EG: Engine E1, E2: Cylinder 1: Common intake passage 2: Branch intake passage 11: First fuel injection valve (for port injection)
12: Second fuel injection valve (for in-cylinder injection)
32: Sensor (for detecting throttle opening)
33: Sensor (for detecting vehicle speed)
34: Sensor (for detecting engine speed)
35: Sensor (for detecting the pressure in the fuel tank)
41: First path 42: Second path (for low fuel pressure)
50: Pressure reducing valve 71: AC motor 80: High voltage battery (power storage device)
81: DC-AC converter 83: Generator

Claims (6)

An engine fuel supply method comprising a port injection means for supplying fuel to an intake passage of an engine as a fuel supply means,
When the supply pressure of the fuel to the port injection means is lower than a predetermined pressure, the minimum fuel amount supplied to the engine is increased and corrected as compared with the case where the pressure is higher than the predetermined pressure;
The fuel supply method of the engine characterized by the above-mentioned. In claim 1,
The fuel is a gaseous fuel,
The fuel supply means further includes a direct injection means for directly injecting fuel into the cylinder of the engine,
When the fuel supply pressure to each of the injection means is equal to or higher than the predetermined pressure, at least a part of the fuel is supplied from the direct injection means, while when the fuel supply pressure to each of the injection means falls below the predetermined pressure , Supplying fuel only from the port injection means,
The fuel supply method of the engine characterized by the above-mentioned. In claim 1 or claim 2,
A vehicle receives at least one of an engine, a generator driven by the engine, a power storage device that receives power generated from the power generator, and power that is generated from the power generator and power that is discharged from the power storage device. With a motor for driving the vehicle,
A first operating region in which the vehicle is driven to travel by the motor without driving the engine, and a second operating region in which the required output is set larger than the first operating region to drive the vehicle while driving the engine are set. And
In the second operating region, when the fuel supply pressure falls below the predetermined pressure, the minimum fuel amount supplied to the engine is corrected to be increased and the first operating region is expanded.
The fuel supply method of the engine characterized by the above-mentioned. Port injection means for supplying fuel to the intake passage of the engine;
Supply pressure detection means for detecting the supply pressure of fuel to the port injection means;
A controller that receives the output from the supply pressure detection means and controls the port injection means;
With
The controller increases and corrects the minimum amount of fuel supplied from the port injection means to the engine when the supply pressure detected by the supply pressure detection means falls below a predetermined pressure, compared to when the supply pressure is higher than the predetermined pressure. ,
A fuel supply device for an engine. In claim 4,
The fuel is a gaseous fuel,
Direct injection means for directly injecting fuel into the cylinder of the engine;
The controller is set to control the port injection means and the direct injection means;
The controller supplies at least part of the fuel from the direct injection means when the supply pressure detected by the supply pressure detection means is equal to or higher than the predetermined pressure, while the supply pressure detected by the supply pressure detection means When the pressure falls below the predetermined pressure, fuel is supplied only from the port injection means.
A fuel supply device for an engine. In claim 4 or claim 5,
A vehicle receives at least one of an engine, a generator driven by the engine, a power storage device that receives power generated from the power generator, and power that is generated from the power generator and power that is discharged from the power storage device. With a motor for driving the vehicle,
The controller includes a first operation region in which the vehicle is driven to travel by the motor without driving the engine, and a second operation in which the vehicle is driven to travel while driving the engine with a required output larger than the first operation region. Area and remember
When the fuel supply pressure detected by the supply pressure detection means falls below the predetermined pressure in the second operation region, the controller corrects the minimum amount of fuel to be supplied to the engine and corrects the increase in the first operation region. To enlarge the
A fuel supply device for an engine.

Images