JP2008190407A - Control device of vehicle equipped with dual fuel engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress drop of an electric storage amount of a battery while suppressing increase of exhaust emission as much as possible in a situation requiring power supply to a motor from the battery when engine operation control is being executed by using hydrogen as fuel, in a hybrid vehicle equipped with a dual fuel engine. <P>SOLUTION: In executing engine operation control by using hydrogen as fuel (yes in step SA5), when target supply power of a motor 17 (power required for the motor 17) exceeds the maximum power generated by a generator 13 obtained by using hydrogen as fuel, and an electric storage amount of the battery is set below a predetermined value (yes in step SA7), a mixture fuel of hydrogen and gasoline is used as a fuel. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention belongs to a technical field related to a control device for a vehicle including a dual fuel engine.

  2. Description of the Related Art Conventionally, there has been known a dual fuel engine that improves exhaust emission by switching and using two fuels having different engine torques when used under the same engine operating conditions. For example, in Patent Document 1, it is possible to switch between CNG (gaseous fuel) and gasoline fuel (liquid fuel) having a larger engine torque under the same engine operating conditions than CNG.

  Moreover, in general, as a hybrid vehicle having an engine and a motor and excellent in fuel efficiency, the engine power is exclusively used for power generation of a generator and is driven only by the power of the motor, and the engine and motor The parallel system and the series / parallel system are known.

  In the series type hybrid vehicle, the motor is driven by power supplied from at least one of a battery and a generator, and is connected to a drive wheel of the vehicle to transmit power to the drive wheel. It is configured to be possible. On the other hand, in the parallel type or series / parallel type hybrid vehicle, the motor can be driven by at least the power supplied from the battery, and is connected to the drive wheel of the vehicle together with the engine to power the drive wheel. It is configured to be able to communicate.

In the series, parallel, or series / parallel hybrid vehicle, when the required vehicle power required for driving the drive wheels cannot be provided only by the engine power, power is supplied from the battery to the motor. There is known a battery assist technique in which driving of a vehicle is assisted by power of a motor that is supplied and obtained by supplying the electric power.
JP 2003-293807 A

  By the way, in recent years, while global warming is largely handled as an environmental problem, there is a demand for the development of a vehicle (automobile) having excellent fuel efficiency while suppressing the generation of exhaust emissions.

  Therefore, it is conceivable to mount the dual fuel engine shown in Patent Document 1 described above on a hybrid vehicle having an engine and a motor and having excellent fuel efficiency.

  In this case, in order to reduce the exhaust emission, it is desirable to operate the engine using the gaseous fuel that uses less exhaust emission when used than the liquid fuel.

  However, when the engine is operated using gaseous fuel as the fuel used, the engine power (power output from the engine) is also lower because the engine torque is lower than when using liquid fuel as the fuel. In some cases, the power required by the engine alone cannot provide the required vehicle power.

  In view of this, it is conceivable that the above-described battery assist technology is introduced into the hybrid vehicle having the dual fuel engine to assist the driving of the vehicle and satisfy the required power of the vehicle.

  However, when the battery assist technology is introduced, when the engine is operated using gaseous fuel as the fuel to be used, the engine power is lower than when the liquid fuel is used, so that power is frequently supplied from the battery to the motor. As a result, there is a problem that the amount of electricity stored in the battery tends to decrease.

  Therefore, when the amount of electricity stored in the battery has fallen, the power supply from the battery to the motor is suppressed by switching the fuel used to liquid fuel and increasing the engine power, thereby preventing a reduction in the amount of electricity stored in the battery. However, there is a problem that exhaust emission increases by using liquid fuel as the fuel.

  The present invention has been made in view of such a point, and the object of the present invention is to improve the configuration and the control method of a hybrid vehicle equipped with a dual fuel engine so that gaseous fuel can be produced. In the case where engine operation control is being performed as the fuel to be used, and when it is necessary to supply power from the battery to the motor, an attempt is made to suppress a decrease in the amount of charge of the battery while suppressing an increase in exhaust emission as much as possible. is there.

  In order to achieve the above object, according to the present invention, when engine operation control is performed using gaseous fuel as a used fuel, the vehicle required power is obtained only by the engine power obtained by using the gaseous fuel as the used fuel. When the battery could not be satisfied and the stored amount of the battery became a predetermined amount or less, a mixed fuel of gaseous fuel and liquid fuel was used as the used fuel.

  Specifically, according to the first aspect of the present invention, as the fuel to be used, the liquid fuel and the gaseous fuel capable of reducing the exhaust emission while reducing the engine power under the same engine operating condition as compared with the liquid fuel and the liquid. The present invention is directed to a vehicle control device including a dual fuel engine that can be used by switching between a fuel and a mixed fuel obtained by mixing the gaseous fuel at a predetermined mixing ratio.

  And a generator that can be driven by the engine, a battery that is charged with at least power generated from the generator, and is connected to a drive wheel of the vehicle, and receives power from at least one of the generator and the battery. , A motor for driving the driving wheel, a battery storage amount detecting means for detecting the storage amount of the battery, and a request required for the motor to obtain a vehicle required power required for driving the driving wheel. Battery discharging means capable of discharging the power of the difference between the required power and the generated power of the generator from the battery to supply the motor when the power exceeds the generated power of the generator; Engine operation control means for performing engine operation control using one of the liquid fuel, the gaseous fuel, and the mixed fuel as a used fuel, and the engine When the engine control is performed using the gaseous fuel as the operating fuel, the operation control means is configured such that the required power exceeds the maximum generated power of the generator obtained by using the gaseous fuel as the operating fuel, and the battery When the fuel switching condition that the stored amount of the battery detected by the stored amount detecting means is less than or equal to the predetermined amount is satisfied, the gaseous fuel is used as the used fuel by switching the used fuel from the gaseous fuel to the mixed fuel. As compared with the above, it is assumed that the discharge power from the battery to the motor by the battery discharge means is reduced by increasing the power of the engine and increasing the power generated by the generator.

  With this configuration, in the so-called series-type hybrid vehicle in which the engine is used exclusively for power generation and travels only by the power of the motor, the engine operation control means performs engine operation control using gaseous fuel as the used fuel. In addition, the required power of the motor exceeds the maximum generated power of the generator obtained by using the gaseous fuel as the used fuel, and the charged amount of the battery detected by the battery charged amount detecting means is not more than a predetermined amount. When the fuel switching condition is satisfied, that is, when it is necessary to supply electric power from the battery to the motor and the stored amount of the battery is less than a predetermined amount, the fuel used is switched from the gaseous fuel to the mixed fuel. Compared to the case where is used fuel, the power of the engine (power output from the engine) is increased to By the battery discharging means by increasing the generated power can be reduced discharge power discharged to the motor from the battery.

  That is, the mixed fuel is a fuel obtained by mixing a gaseous fuel and a liquid fuel having higher engine power than the gaseous fuel at a predetermined mixing ratio. By switching from the gas fuel to the mixed fuel, the engine power increases, and accordingly, the generated power of the generator driven by the engine also increases. As a result, since the difference between the motor required power and the power generated by the generator is reduced, the power supplied from the battery to the motor by the battery discharging means is also reduced.

  Therefore, when engine operation control is being performed using gaseous fuel as the fuel to be used, when the battery needs to be discharged and the battery charge is below a predetermined level, A decrease in the amount can be suppressed.

  By the way, the above-mentioned liquid fuel fuel is assumed to have more exhaust emissions during use than gaseous fuel. For this reason, if the fuel used is switched to liquid fuel when the fuel switching condition is satisfied, the battery power is increased due to an increase in engine power. Although it is possible to suppress the decrease in the amount of stored electricity, there is a problem that the exhaust emission is increased.

  However, according to the present invention, when the fuel switching condition is satisfied, the used fuel is switched to the mixed fuel of the liquid fuel and the gaseous fuel capable of reducing the exhaust emission as compared with the liquid fuel. While suppressing the increase as much as possible, it is possible to suppress a decrease in the amount of electricity stored in the battery.

  According to the second aspect of the present invention, as the fuel to be used, the liquid fuel and the gaseous fuel capable of reducing the exhaust emission while the engine power under the same engine operating condition is lower than that of the liquid fuel, the liquid fuel, and the gaseous fuel. The present invention is directed to a control device for a vehicle including a dual fuel engine that can be used by switching between a mixed fuel in which the fuel is mixed at a predetermined mixing ratio.

  A generator that can be driven by the engine, a battery that is charged with at least power generated from the generator, and connected to the driving wheels of the vehicle, together with the engine that is supplied with power from the battery. A motor capable of transmitting power to the drive wheels; battery storage amount detection means for detecting the storage amount of the battery; and vehicle demand power required to drive the drive wheels exceeds the engine power. Battery discharge means capable of discharging the battery and supplying the discharge power to the motor so that the difference power between the vehicle required power and the engine power can be supplied by the motor, the liquid fuel, the gas fuel, and Engine operation control means for performing engine operation control using one of the mixed fuels as a used fuel, and the engine operation control means includes: When engine operation control is performed using gaseous fuel as the fuel used, the vehicle required power exceeds the maximum engine power obtained by using the gaseous fuel as the fuel used, and the battery storage amount detection means detects When the fuel switching condition in which the storage amount of the battery is equal to or less than the predetermined amount is satisfied, the engine power is switched by switching the fuel used from the gaseous fuel to the mixed fuel, compared with the case where the gaseous fuel is used as the used fuel. It is assumed that the discharge power from the battery to the motor by the battery discharging means is reduced by increasing the power.

  With this configuration, in a so-called parallel type or series / parallel type hybrid vehicle that travels with power from both the engine and the motor, when the engine operation control is performed using the gaseous fuel as the used fuel, the gaseous fuel is used. When the fuel switching condition is established in which the required power of the vehicle exceeds the maximum engine power obtained by using the fuel and the battery storage amount detected by the battery storage amount detection means is equal to or less than a predetermined amount, the fuel used is Discharge power discharged from the battery to the motor by the battery discharging means by increasing the power of the engine by switching from the gaseous fuel to the mixed fuel as compared with the case where the gaseous fuel is used as a fuel. Can be reduced. Therefore, the same effect as that of the invention of claim 1 can be obtained.

  According to a third aspect of the invention, in the first or second aspect of the invention, the mixing ratio of the mixed fuel is configured to change according to the magnitude of the vehicle required power while the fuel switching condition is established. Shall.

  As a result, it is possible to more reliably suppress a decrease in the amount of power stored in the battery while the fuel switching condition is established.

  That is, for example, when the vehicle required power increases while the fuel switching condition is established, the mixing ratio of the mixed fuel is changed so that the ratio of the liquid fuel in the mixed fuel increases in accordance with the increase, thereby It is possible to increase the power to increase the power generated by the generator driven by the engine. Accordingly, the discharge power from the battery to the motor is reduced in accordance with the magnitude of the required vehicle power, and this makes it possible to more reliably suppress a reduction in the amount of electricity stored in the battery.

  According to a fourth aspect of the present invention, in the first or second aspect of the present invention, the amount of charge of the battery detected by the battery charge amount detecting means while the fuel switching condition is satisfied is less than the predetermined amount and more than the predetermined amount. When it is within the range of the set amount that is set low, the mixing ratio of the mixed fuel is assumed to be a constant value.

  As a result, when the fuel switching condition is satisfied and the stored amount of the battery is equal to or less than the predetermined amount and within a set amount that is set lower than the predetermined amount, a decrease in the stored amount of the battery is suppressed. On the other hand, it is possible to more reliably suppress an increase in exhaust emission.

  That is, for example, when the vehicle required power increases while the fuel switching condition is satisfied, the ratio of liquid fuel is increased in accordance with the increase by setting the mixing ratio to a constant value regardless of the increase in the vehicle required power. Compared with the case where it does in this way, the increase in the exhaust emission by the increase in liquid fuel can be suppressed.

  According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the mixing ratio of the mixed fuel is such that the amount of charge of the battery detected by the battery charge amount detecting means is less than the set amount while the fuel switching condition is satisfied. When it is, it shall be comprised so that it may change according to the magnitude | size of the said vehicle request | requirement power.

  As a result, when the fuel switching condition is satisfied and the stored amount of the battery is less than the set amount set lower than the predetermined amount, the stored amount of the battery is further reduced as in the third aspect of the invention. It becomes possible to suppress it reliably.

  In the invention of claim 6, in the invention of claims 1 to 5, the mixing ratio of the mixed fuel is a value such that the amount of the gaseous fuel contained in the mixed fuel is larger than the amount of the liquid fuel. It shall be said that.

  As a result, an increase in exhaust emission during the establishment of the fuel switching condition can be more reliably suppressed.

  As described above, according to the control apparatus for a vehicle equipped with the dual fuel engine of the present invention, the engine is used only for power generation, and the gas fuel is used in the series type hybrid vehicle that travels using only the motor as the driving source. When engine operation control is performed as fuel, when it is necessary to supply power from the battery to the motor, it is possible to suppress a decrease in the stored amount of the battery while suppressing an increase in exhaust emission as much as possible.

  According to another aspect of the present invention, there is provided a control device for a vehicle including a dual-fuel engine. In a parallel-type or series-parallel type hybrid vehicle that can run using both an engine and a motor as a drive source, The same effect as a vehicle can be obtained.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a vehicle 1 including a dual fuel engine (hereinafter referred to as an engine) 11 on which a control device according to an embodiment of the present invention is mounted. The vehicle 1 includes an engine 11 and a motor 17 as power sources. The engine 11 is used only for power generation, and all the power for moving the vehicle 1 depends on an AC motor 17 (hereinafter referred to as a motor 17). It is a series hybrid vehicle. In addition to the engine 11 and the motor 17, the vehicle 1 includes a high voltage battery 12 (hereinafter referred to as a battery 12), a generator 13 as a generator (alternator) driven by the engine 11, and a generator 13. An AC-DC converter 20a that converts AC power generated at the DC to DC power, and a DC-AC converter 20b that converts AC power supplied from at least one of the AC-DC converter 20a and the battery 12 to DC power. I have. The AC-DC converter 20a and the DC-AC converter 20b are connected in series with each other in a state where the AC-DC converter 20a is connected to the generator 13 and the DC-AC converter 20b is connected to the motor 17, A power path 40 for supplying power from the battery 12 is connected to a connection line between the AC-DC converter 20a and the DC-AC converter 20b.

  The engine 11 uses gasoline (liquid fuel) as the fuel and reduces exhaust emissions while lowering the engine torque when used under the same operating conditions as in gasoline, that is, at the same engine speed and throttle opening. It is configured to be able to switch between possible hydrogen (gaseous fuel) and mixed fuel in which hydrogen and gasoline are mixed at a predetermined mixing ratio (mass ratio) (see FIG. 3).

  Here, the engine power (power output from the output shaft of the engine 11) is calculated by the product of the engine torque and the engine speed, so that when gasoline is used as fuel under the same operating conditions, Is larger than when hydrogen is used as the fuel.

  Accordingly, the engine 11 mixes gasoline, hydrogen, and hydrogen, which can reduce exhaust emissions, while using gasoline as the fuel to be used and lowering engine power under the same engine operating conditions as compared to the gasoline. It can also be said that it is configured to be usable by switching between the mixed fuel.

  For this reason, when driving the motor 17 with electric power from the generator 13 driven by the engine 11, such as during high torque operation and medium torque operation, which will be described later, hydrogen is used as fuel by using gasoline as fuel. Compared with the case of the above, larger power can be transmitted to the rotor (not shown) of the generator 13, and as a result, more electric power can be supplied from the generator 13 to the motor 17. Therefore, the power of the motor 17 (power output from the output shaft of the motor) is also the same when the gasoline is used as the used fuel at the same engine speed and throttle opening as compared with the case where hydrogen is used as the used fuel. growing.

  As shown in FIG. 2, the engine 11 includes a rotor housing chamber (hereinafter referred to as a cylinder) 23 surrounded by a bowl-shaped rotor housing having a trochoid inner peripheral surface and a side housing. It is configured to be accommodated, and three working chambers are defined on the outer peripheral side of the rotor 24. Although not shown, the engine 11 is integrated with two rotor housings sandwiched between three side housings, and the rotors 24 and 24 are accommodated in two cylinders 23 and 23 formed therebetween, respectively. FIG. 2 shows the two rotors 23 and 23 in an expanded state.

  Each of the rotors 24 rotates while rotating around the eccentric shaft 25 in a state where seal portions respectively disposed at three tops of the outer periphery of the rotor 24 are in contact with the inner surface of the trochoid of the rotor housing. Revolves around 25 axes. Then, while the rotor 24 makes one rotation, the working chambers formed between the tops of the rotor 24 move in the circumferential direction, and the intake, compression, expansion (combustion), and exhaust strokes are performed. Is generated from the eccentric shaft 25 via the rotor 24.

  Each cylinder 23 of the engine 11 is provided with two spark plugs 14, 14. The two spark plugs 14, 14 are respectively disposed near the minor axis of the rotor housing, The cylinders 23 are each provided with two hydrogen injection injectors 4 for directly injecting hydrogen supplied from the hydrogen fuel tank 16 (see FIG. 1) into the cylinder (one in each cylinder 23 in FIG. 2). 2), the two injectors 4 provided in each cylinder 23 are arranged in the axial direction of the eccentric shaft 25 in the vicinity of the long axis of the rotor housing.

  In addition, the intake passage 2 communicates with each cylinder 23 so as to communicate with the working chamber in the intake stroke, and the exhaust passage communicates with the working chamber in the exhaust stroke. The intake passage 2 is one on the upstream side, but is divided into two on the downstream side and communicates with the working chambers of the cylinders 23. Further, an exhaust purification device 30 using a three-way catalyst (catalyst) is disposed in the middle of the exhaust passage 29 in order to purify harmful components such as HC, CO, NOx in the exhaust gas.

  A throttle valve 22 that is driven by an actuator 21 such as a stepping motor and adjusts the cross-sectional area (valve opening) of the passage 2 is disposed upstream of the branch portion of the intake passage 2. Downstream of the section, gasoline injectors 5 and 5 for injecting gasoline supplied from the gasoline fuel tank 15 (see FIG. 1) into the intake passage 2 (branched portion) are arranged. Yes.

  The ignition plug 14, the actuator 21 of the throttle valve 22, and the injectors 4 and 5 for hydrogen and gasoline injection are controlled by a powertrain control module 6 (hereinafter referred to as PCM 6) as engine operation control means. It has become so.

  That is, each spark plug 14 is ignited at a predetermined timing according to the rotational position of the rotor 24. The actuator 21 of the throttle valve 22 is controlled by the PCM 6 according to the output signal of the accelerator opening sensor 33 (see FIG. 2) that detects the amount of depression of the accelerator pedal (accelerator opening) of the occupant of the vehicle 1. The opening degree of the valve 22 is adjusted. That is, the opening value of the throttle valve 22 corresponds to the output value of the throttle opening sensor 33 (in this embodiment, the actuator 21 also serves as an actuator 21) that detects the opening. And adjust to a predetermined value. Further, the injector 4 for hydrogen injection injects hydrogen into the cylinder 23 (working chamber) at a predetermined timing according to the rotational position of the rotor 24 when the fuel used is hydrogen, and the injector 5 for gasoline injection. Injects gasoline into the intake passage 2 at a predetermined timing according to the rotational position of the rotor 24 when the fuel used is gasoline.

  The motor 17 is controlled by a motor controller 27 (see FIG. 2), which will be described later, which operates in response to a control signal from the PCM 6, and is connected to both drive wheels 18 via a differential gear 19. ing.

  The motor 17 has an output torque required when the required power required for driving the drive wheels 18 (hereinafter referred to as vehicle required power) is low, such as during constant speed operation of the vehicle 1. During low-torque operation or when the vehicle is started (hereinafter referred to as “motor required torque”), it is driven by electric power supplied from the battery 12 (EV traveling), and is supplied from the generator 13 driven by the engine 11 during medium-torque operation. When the vehicle required power is high, such as during rapid acceleration, that is, when the motor required torque is high and the torque is high, the vehicle required power is satisfied only with the power from the generator 13. The battery is driven by the power supplied from both the battery 12 and the generator 13 (hereinafter referred to as the battery). It called a cyst state. See Fig. 5). In the present embodiment, when the engine is operated using gasoline with a large engine torque as the fuel to be used, the generator 13 can generate enough power to satisfy the vehicle required power. Battery assist during torque operation is not performed (see FIG. 4). The vehicle required power is calculated by the PCM 6 based on a vehicle speed detected by a vehicle speed sensor 32 described later and an accelerator opening detected by an accelerator opening sensor 33.

  The battery 12 is controlled in operation by a battery controller 28 (see FIG. 2), which will be described later, which operates in response to a control signal from the PCM 6. That is, the charging / discharging operation and charging / discharging power of the battery 12 are controlled by the battery controller 28. The battery 12 receives necessary signals from the battery controller 28 during the low torque operation and the high torque operation. While supplying predetermined electric power to the motor 17 by discharging, when the amount of electricity stored is insufficient (when it is determined by the PCM 6 that the amount of electricity stored is equal to or less than the predetermined amount of charge required for charging), Based on the signal from the battery controller 28, the generator 13 is supplied with power and charged.

  The generator 13 has its generated power (power generation amount) controlled by a generator controller 26 (described later) that operates in response to a control signal from the PCM 6.

  The AC-DC converter 20 a and the DC-AC converter 20 b are controlled by the motor controller 27 and the battery controller 28 to perform power conversion among the battery 12, the generator 13, and the motor 17.

  Each signal is input to the PCM 6 from a battery current / voltage sensor 31, a vehicle speed sensor 32, an accelerator opening sensor 33, and a fuel changeover switch 34.

  The PCM 6 controls the generator controller 26, the motor controller 27, the battery controller 28, and the devices of the engine 11 such as the injectors 4 and 5 based on the input signals by outputting necessary signals.

  The battery current / voltage sensor 31 detects the current intensity and voltage of the battery 12. When the battery current / voltage sensor 31 detects the current intensity and voltage of the battery 12, the battery current / voltage sensor 31 outputs a detection signal to the PCM 6. When the PCM 6 receives the detection signal from the battery current / voltage sensor 31, the PCM 6 calculates the storage amount of the battery 12 and the charge / discharge amount of the battery 12. Thus, the battery current / voltage sensor 31 and the PCM 6 constitute a battery charge amount detection means for detecting the charge amount of the battery 12.

  The accelerator opening sensor 33 detects the opening of an accelerator (not shown) of the vehicle 1 and outputs a detection signal to the PCM 6 when the accelerator opening is detected.

  The vehicle speed sensor 32 detects the vehicle speed of the vehicle 1 and outputs a detection signal to the PCM 6 when the vehicle speed is detected.

  The fuel changeover switch 34 is for selecting a fuel required by the occupant as the fuel to be used (hereinafter referred to as occupant required fuel) from gasoline and hydrogen, and is a navigation provided on an instrument panel (not shown). An occupant can display instructions on a touch panel display 74 (see FIG. 11) of the apparatus. In the present embodiment, the fuel changeover switch 34 is configured so that one of gasoline and hydrogen can be selected as the occupant demand fuel. However, the present invention is not limited to this. You may comprise so that a fuel can be selected.

  As shown in FIG. 11, the fuel changeover switch 34 includes a hydrogen selection button 34a for selecting hydrogen and a gasoline selection button 34b for selecting gasoline, and the two buttons 34a, 34b. When one of the buttons is selected by touching the finger with a finger, the selection signal corresponding to the selected button 34a, 34b is continuously output to the PCM 6. Specifically, for example, when the hydrogen selection button 34a is selected, the fuel changeover switch 34 continuously outputs a selection signal corresponding to the button 34a to the PCM 6, and after the selection, the gasoline selection button 34b. When is newly selected, the selection signal is switched to a signal corresponding to the gasoline selection button 34b and continuously output to the PCM 6. The PCM 6 receives the selection signal from the fuel changeover switch 34 and identifies the occupant demand fuel. Specifically, when the PCM 6 receives a selection signal corresponding to the hydrogen selection button 34a, it identifies that the occupant demand fuel is hydrogen, and when it receives a selection signal corresponding to the gasoline selection button 34b, The required fuel is identified as gasoline.

  The motor controller 27 controls the power conversion of the AC-DC converter 20a and the DC-AC converter 20b based on a control signal from the PCM 6 so that the power supplied from the battery 12 and the generator 13 is AC with a predetermined frequency. This is converted into electric power, thereby controlling the rotation speed and torque of the motor 17.

  Specifically, the motor controller 27 outputs necessary control signals to the AC-DC converter 20a and the DC-AC converter 20b during the medium torque operation and the high torque operation, thereby generating the generator 13. The AC power generated in step 1 is once converted into DC power by the AC-DC converter 20a, and then again converted from DC power to AC power of a predetermined frequency by the DC-AC converter 20b and supplied to the motor 17.

  In addition, the motor controller 27 outputs a necessary control signal to the DC-AC converter 20b during the low torque operation or the high torque operation, so that the DC power discharged from the battery 12 is supplied to the DC-AC. The converter 20 b converts the AC power into a predetermined frequency and supplies it to the motor 17.

  The battery controller 28 controls the charge / discharge operation of the battery 12 and its charge / discharge power based on a control signal from the PCM 6.

  Specifically, when charging the battery 12, the battery controller 28 outputs the necessary control signal to the AC-DC converter 20 a so that the AC power generated by the generator 13 is The AC-DC converter 20 a converts it into DC power having a predetermined voltage and supplies it to the battery 12 through the power path 40.

  The generator controller 26 controls the generated power of the generator 13 by controlling the target load torque applied to the generator 13 based on the control signal from the PCM 6. This target load torque is calculated by PCM6. Specifically, the target load torque is calculated from an operation map (see FIG. 6) of the engine 11 described later based on the generated power required for the generator 13. The target load torque usually coincides with the engine torque.

  Information regarding the operation map is stored in advance in the PCM 6, and this operation map is shown in FIG. Line g and line h are operation lines of the engine 11 when hydrogen and gasoline are used as fuels, respectively, and the combined efficiency of the engine 11 and the generator 13 is the best in generating a predetermined amount of power in the generator 13. It is preset so that Here, in the region where the engine speed is lower than about 4000 rpm, the line g is located above the line h. That is, except for the battery assist state, the engine torque when the engine 11 is operated using gasoline as the used fuel is larger at the same engine speed than when the engine 11 is operated using hydrogen.

  Line R and Line Q are lines indicating the maximum engine torque when hydrogen and gasoline are used as fuel for the engine 11, respectively, and the maximum engine torque line Q when gasoline is used as fuel is It is located above the maximum engine torque line R when hydrogen is used as the fuel. That is, the maximum engine torque at the same engine speed is greater when the engine 11 is operated using gasoline as the fuel than when hydrogen 11 is used.

  Here, the operating line h of the engine 11 when hydrogen is used as a fuel is a line where the engine speed is constant (4000 rpm in this embodiment) at the intersection with the maximum torque line R. A line with a constant rotation speed corresponds to a battery assist state (the state at the time of high torque operation) in which power is supplied from the battery 12 to the motor 17 when the power generation by the generator 13 reaches the limit.

  Here, the driving line h is depicted as if the engine torque increases while the engine speed remains constant in the battery assist state, but in reality, the engine torque remains constant and increases. The minute torque (torque corresponding to S in FIG. 6) indicates the torque of the motor 17 (battery assist torque) increased by the power supply from the battery.

  The operation line g of the engine 11 when gasoline is used as a fuel does not have a line with a constant rotation speed as described above. That is, when the engine 11 is operated using gasoline as the fuel used, the engine torque is higher than that when hydrogen is used as the fuel. Therefore, battery assist is not performed and the generated power from the generator 13 driven by the engine 11 is not generated. Only the power supplied to the motor 17 is covered.

A plurality of lines P arranged in the vertical direction are equal output lines of the motor 17 and indicate lines where the output of the motor 17 is constant, that is, lines where the power supplied to the motor 17 is constant (constant power supply line). Yes. Therefore, except for the battery assist state, the power supplied to the motor 17 and the power generated by the generator 13 are equal to each other. Therefore, the power generated by the generator 13 (power generation amount) is constant for each of the plurality of lines P. It can also be said that it is a power generation line. Here, each line P corresponds to a line of electric power Pn (kw) supplied to the motor 17 (a line of generated electric power Pn (kw) of the generator 13), and the line located at the upper side, that is, the subscript n becomes larger. The generated power increases. That is, P ₁ <P ₂ <P ₃ ... <P _n . In the following description, the plurality of lines P are referred to as an equal power generation amount line of the generator 13 or a constant power supply line to the motor 17.

Further, a plurality of lines η _h and η _g drawn concentrically indicate lines having a constant combination efficiency when hydrogen and gasoline are used as fuels for the engine 11, respectively. As the subscript n (in FIG. 4, only n = 1 to 6) is increased, the efficiency is lowered. That is, η ₁ <η ₂ <η ₃ ... <Η _n .

Here, the point D on the operation line g corresponds to an engine operation state in which the combined efficiency becomes the maximum efficiency η ₁ when gasoline is used as fuel, and the generated power of the generator 13 in this state is P ₇ ( kw). Further, point B on the operation line h corresponds to an engine operation state in which the combined efficiency becomes the maximum efficiency η ₁ when hydrogen is used as fuel, and the generated power of the generator 13 in this state is P ₄ (kw ). When gasoline is used as the fuel for the engine 11, as shown in the operation line g, the combination efficiency also decreases as the engine torque decreases in the region where the generated power is P ₇ (kw) or less. Further, when hydrogen is used as the fuel for the engine 11, as shown in the operation line h, the combination efficiency also decreases as the engine torque decreases in the region where the generated power is P ₄ (kw) or less.

  The PCM 6 calculates the vehicle required power necessary for driving the drive wheels 18 based on detection signals from the accelerator opening sensor 33 (see FIG. 2) and the vehicle speed sensor 32, and obtains the vehicle required power. The required power required for the motor 17 (hereinafter referred to as motor required power) is calculated. Further, the PCM 6 calculates a target supply power (required power required for the motor 17) to be supplied to the motor 17 in order to obtain the required motor power.

  Further, when the calculated target supply power (required power required for the motor 17) exceeds the generated power of the generator 13, the PCM 6 outputs a control signal necessary for the battery controller 28 to output the target control power. While the difference power between the supplied power and the generated power of the generator 13 can be discharged from the battery 12 and supplied to the motor 17, the target supplied power (required power required for the motor 17) is generated by the generator 13. When the electric power is lower than the electric power, the electric power of the difference between the target supply electric power and the electric power generated by the generator 13 is supplied from the generator 13 to the battery 12 so that the battery 12 can be charged.

  Thus, when the battery controller 28 requires the required power required for the motor 17 in order to obtain the required vehicle power required for driving the drive wheels 18, the generated power of the generator 13 (generator 13) is exceeded. In addition, a battery discharging means that can discharge the power difference between the required power and the power generated by the generator 13 from the battery 12 and supply the power to the motor 17 is configured.

  The PCM 6 performs engine operation control using the occupant-requested fuel selected by the fuel switch 34 as a use fuel, except when a fuel switching condition described later is satisfied (while the fuel switching condition is satisfied).

  In addition, when the engine operation control is performed using hydrogen as a fuel, the PCM 6 uses the target supply power of the motor 17 (requested from the motor 17) as the maximum generated power of the generator 13 obtained by using the hydrogen as a fuel. When the fuel switching condition is satisfied that the stored power amount of the battery 12 is less than or equal to a predetermined stored power amount (which is set to 45% SOC (state of charge) in the present embodiment). Regardless of the occupant demand fuel selected by the fuel changeover switch 34, the fuel used is switched from hydrogen to the mixed fuel, so that the power of the engine 11 is increased compared to the case where hydrogen is used as the fuel. 13 from the battery 12 controlled by the battery controller 28 by increasing the generated power of 13 And it is configured to reduce the discharge power to the chromatography data 17 (refer to FIG. 7 (a) and (b)). It is calculated as SOC (%) = (remaining capacity) / (full charge amount) × 100.

  Further, the PCM 6 controls the fuel injection amount of gasoline and hydrogen to control the fuel injection amount of gasoline and hydrogen according to the magnitude of the vehicle required power, that is, the magnitude of the target supply power to the motor while the fuel switching condition is established. Change the mixing ratio. A specific method for determining the mixing ratio will be described later.

  When the PCM 6 determines that the charged amount of the battery 12 falls below the charge required charged amount (in this embodiment, the SOC is set to 40%) while the fuel switching condition is established, the fuel used is changed from the mixed fuel to the gasoline. By switching, the engine operation control is performed so that the generated power of the generator 13 exceeds the target supply power of the motor 17, and a necessary control signal is output to the battery controller 28. To the battery 12 to charge the battery 12.

  Next, specific processing operations regarding the operation control processing of the engine 11 and the motor 17 in the PCM 6 will be described with reference to FIGS.

  First, in the first step SA1, detection signals output from the vehicle speed sensor 32, the accelerator opening sensor 33, and the battery current / voltage sensor 31 are read and used fuel information (for example, operation signals of the injectors 4 and 5). ).

  In step SA2, the required vehicle power is calculated based on the detection signal read in step SA1. Specifically, the vehicle speed is detected (calculated) based on the detection signal from the vehicle speed sensor 32, and the accelerator opening (calculation) is detected based on the detection signal from the accelerator opening sensor 33. The required vehicle power is calculated from the vehicle speed and the accelerator opening.

  In step SA3, the motor required power is calculated based on the vehicle required power calculated in step SA2, and the target supply power to the motor 17 necessary for obtaining the motor required power (required power required for the motor 17). To decide.

  In step SA4, the charged amount of the battery 12 is calculated based on the detection signal from the battery current / voltage sensor 31 read in step SA1. Specifically, the storage amount of the battery 12 is calculated by calculating charge / discharge power based on the product of the current and voltage calculated based on the detection signal from the battery current / voltage sensor 31.

  In step SA5, it is determined based on the used fuel information read in step SA1 whether or not the used fuel of the engine 11 is hydrogen. If this determination is YES, the process proceeds to step SA6, and if NO. The process proceeds to step SA12.

In step SA6, it is determined whether or not the target supply power to the motor 17 exceeds the maximum generated power P ₇ (generated power corresponding to the T point in FIG. 6) kw of the generator 13 when hydrogen is used as the fuel. If this determination is YES, the process proceeds to step SA7, and if NO, the process proceeds to step SA14.

  In step SA7, it is determined whether or not the battery storage amount is equal to or less than the predetermined storage amount. If this determination is YES, the process proceeds to step SA8, and if it is NO, the process proceeds to step SA14.

  In step SA8, the fuel used is changed to a mixed fuel of hydrogen and gasoline.

  In step SA9, the target engine speed and the target engine torque are provisionally determined.

  The target engine speed and target engine torque are provisionally determined as the engine speed and engine torque corresponding to the operating state required of the engine 11 when hydrogen is used as the fuel.

More specifically, assuming that the target supply power to the motor 17 is P ₁₀ (kw) when the fuel used for the engine 11 is hydrogen, the operation line h of the engine 11 when hydrogen is the fuel used, and An intersection M with the motor supply power constant line P at which the target supply power to the motor becomes P ₁₀ (kw) is determined as an operation point of the engine 11, and this M point is included in the battery assist region as described above. Therefore, the operation point of the engine 11 is actually the T point, and the generated power P ₇ (kw) of the generator 13 in the state of the T point is supplied to the motor 17 and the remaining power (= P ₁₀ − P ₇ (kw)) is covered by the discharged power from the battery 12. Thus, the operating conditions required for the engine 11 when the hydrogen and fuel used is a T point, the engine torque N _T and the engine speed R _T each the target engine speed and the target engine corresponding to the T point Temporarily determined as torque.

  In step SA10, the hydrogen fuel injection amount is determined from the target engine speed and target engine torque provisionally determined in step SA9. Specifically, in this PCM 6, fuel map information (not shown) regarding the fuel injection amount uniquely determined from the engine torque, the engine speed, and the fuel (gasoline or hydrogen) used is stored in advance. The hydrogen fuel injection amount is determined based on the map information.

  In step SA11, a target engine torque is determined by adding a predetermined amount of torque to the tentatively determined target engine torque in accordance with a target supply power (required power of the motor 17) to the motor 17, and the predetermined amount Then, the fuel injection amount of gasoline is determined so as to increase the torque, and the process proceeds to step SA16 (see FIG. 9). Here, a value obtained by dividing a predetermined amount of the added torque by the temporarily determined target engine torque is defined as a torque added width (%).

In the present embodiment, as shown in FIG. 10, when the target supply power to the motor 17 is equal to or greater than P ₇ (kw) and less than P ₈ (kw), the additional torque width is set to 10%. When the supplied power is greater than or equal to P ₈ (kw) and less than P ₉ (kw), the additional torque width is set to 20%, and when the target supplied power is greater than or equal to P ₉ (kw) and less than P ₁₀ (kw), the torque is set. The extra width is set to 30%. That is, the additional torque width is set so as to increase stepwise as the target power supply to the motor 17 increases. Therefore, the fuel injection amount of gasoline also increases stepwise as the target supply power to the motor 17 (required power required for the motor 17) increases. In other words, the mixing ratio of hydrogen and gasoline increases in a step-like manner as the target power supply to the motor 17 increases.

  Note that the torque addition width is set in advance such that the gasoline injection amount is smaller than the hydrogen injection amount. Therefore, in the present embodiment, the amount of hydrogen contained in the mixed fuel is larger than the amount of gasoline at least within the range where the additional width of torque is up to 30%.

  In step SA12, which advances to NO in step SA5, gasoline is continuously used as the fuel used, and the target engine speed and target engine torque of the engine 11 are determined.

More specifically, for example, when the target supply electrical power to the motor 17 is determined to _P 11 (kw) at step SA3, as illustrated in FIG. 6, the electric power supplied to the motor 17 is _P 11 (kw) become the intersection a of the motor supply constant power line P and the fuel used and the engine operating line g when formed into a gasoline is determined as the operating conditions required for the engine 11, the engine torque N _a and the engine corresponding to the point a The rotation speed R _A (approximately 4500 rpm in the present embodiment) is determined as the target engine torque and the target engine rotation speed, respectively.

  In step SA13, the fuel injection amount of gasoline is determined based on the fuel map information from the target engine speed and target engine torque determined in step SA12, and the process proceeds to step SA16 (see FIG. 9).

  In step SA14 which proceeds when NO in step SA6 and step SA7, the target engine speed and the target engine torque are calculated.

Specifically, for example, when the target supply power to the motor 17 is determined to be P ₄ (<maximum generated power P ₇ of the generator 13) kw in step SA3 (NO in step SA6), FIG. As shown in FIG. 5, the intersection B between the motor supply power constant line P where the supply power to the motor 17 is P ₄ (kw) and the engine operation line h when the fuel used is hydrogen is the operation required for the engine 11. It is determined as a state, _{(approximately} 2300rpm in the present embodiment) engine torque N _B and the engine speed R _B corresponding to the point B is determined as the target engine torque and the target engine speed, respectively.

When the target supply power to the motor 17 is determined to be P ₁₀ (> maximum generated power P ₇ of the generator 13) kw (YES in step SA6), as described above, point M in FIG. Is the operating point of the engine 11, but since the M point is included in the battery assist region, the operating point of the engine 11 is actually the T point, and the generated power P ₇ of the generator 13 in the state of the T point is (Kw) is supplied to the motor 17 and the remaining electric power (= P ₁₀ −P ₇ (kw)) is supplied from the electric power from the battery 12. Thus, the operating conditions required for the engine 11 when the hydrogen and fuel used is a T point, the engine torque N _T and the engine speed R _T each the target engine speed and the target engine corresponding to the T point Temporarily determined as torque.

  In step SA15, the fuel injection amount of hydrogen is determined based on the fuel map information from the target engine speed and target engine torque determined in step SA14, and the process proceeds to step SA16 (see FIG. 9).

  In step SA16, the predicted generated power of the generator 13 is calculated based on the target engine torque and the target engine speed calculated in steps SA11, SA12, and SA14. Here, the predicted generated power of the generator 13 is generated power that is expected to be generated by the generator 13 when the engine 11 is operated at the calculated target engine torque and target engine speed.

  Specifically, the predicted generated power of the generator 13 is calculated by the product of the target engine speed, the target engine torque, and the power generation efficiency of the generator 13.

  That is, (predicted power generation of generator 13) = (target engine speed) × (target engine torque) × (power generation efficiency of generator 13).

  Note that, in a region where battery assist is not performed, the predicted generated power of the generator 13 is equal to the power supplied to the motor 17, and therefore the predicted generated power of the generator 13 is calculated based on the engine torque as described above. Instead of this, the predicted generated power of the generator 13 may be calculated as the target supply power to the motor 17.

  In step SA17, the carry-out power (discharge power) from the battery 12 is calculated and it is determined whether or not the carry-out power is less than 0 kW. If this determination is YES, the discharge power from the battery 12 is supplied to the motor 17. If it is not necessary, the process proceeds to step SA18. If NO, that is, if it is necessary to supply the discharge power from the battery 12 to the motor 17, the process proceeds to step SA21.

  Here, the carry-out power from the battery 12 is calculated as (take-out power from the battery 12) = (target supply power to the motor 17) − (expected power generation of the generator 13).

  In step SA18, it is determined whether or not the predicted generated power of the generator 13 calculated in step SA16 exceeds the target supply power to the motor 17. If this determination is YES, the process proceeds to step SA19, and if NO The process proceeds to step SA23.

  In step SA19, control signals corresponding to the fuel injection amounts of hydrogen and gasoline determined in steps SA8 and SA10 are output to the injectors 4 and 5, and a predetermined signal is supplied to the actuator 21 of the throttle valve 22. By outputting a control signal so that the throttle valve opening is reached, the engine 11 is operated at the target engine torque and the target engine speed. Here, the predetermined throttle valve opening is a valve opening that can secure the intake air amount necessary for burning the determined injection amount of hydrogen and gasoline. When hydrogen is used as fuel, the fuel injection amount of gasoline is 0, and when gasoline is used as fuel, the fuel injection amount of hydrogen is 0.

  The generator controller 26 outputs a control signal so that the load torque of the generator 13 becomes equal to the target engine torque, and causes the generator 13 to generate power.

  In step SA20, all the generated power of the generator 13 is supplied to the motor 17 by outputting a necessary control signal to the motor controller 27.

  In step SA21 that proceeds to NO in step SA17, the same processing as in step SA19 is performed, and thus the description thereof is omitted.

  In step SA22, a necessary control signal is output to the motor controller 27 to supply all the generated power of the generator 13 to the motor 17, and a necessary control signal is also output to the battery controller 28. The electric power equal to the carry-out electric power (calculated in step SA17) is discharged from the battery 12 and supplied to the motor 17.

  In step SA23, which advances to NO in step SA18, the same processing as step SA19 is performed, and thus the description thereof is omitted.

  In step SA24, by outputting a necessary control signal to the motor controller 27, the power corresponding to the target supply power to the motor 17 among the generated power of the generator 13 is supplied to the motor 17, and By outputting a necessary control signal to the battery controller 28, surplus power that is not supplied to the motor 17 among the generated power of the generator 13 is supplied to the battery 12 to charge the battery 12.

  As described above, in the first embodiment, the PCM 6 determines that the fuel switching condition is satisfied (step SA7) when the engine operation control is performed using hydrogen as a fuel (YES in step SA5). If YES, the engine 11 is switched from hydrogen to the mixed fuel regardless of the occupant demand fuel selected by the fuel changeover switch 34, compared with the case where hydrogen is used as the fuel. The power generated by the generator 13 is increased to increase the power generated by the generator 13, thereby reducing the discharge power from the battery 12 to the motor 17 controlled by the battery controller 28. As a result, as shown in FIG. 7B, after the fuel to be used is switched from hydrogen to the mixed fuel due to the establishment of the fuel switching condition, the rate of decrease in the charged amount of the battery 12 (corresponding to the slope of the straight line in the figure). It is possible to suppress a decrease in the amount of electricity stored in the battery 12.

  Further, since the fuel used is switched from hydrogen to the mixed fuel when the fuel switching condition is satisfied, an increase in exhaust emission can be suppressed as compared with the case where the fuel is switched from hydrogen to gasoline.

  Further, as described above, the rate of decrease in the stored amount of the battery 12 decreases due to the establishment of the fuel switching condition. For this reason, after the fuel switching condition is satisfied, the stored amount of the battery 12 reaches the charge required storage amount. Can extend the time. Therefore, the chargeable opportunity that the battery 12 can be charged in a state where hydrogen with low engine power is used as fuel (the target supply power to the motor 17 is lower than the maximum generated power of the generator 13 when using hydrogen, It is possible to wait for a long time until the battery 12 can be charged in a state where hydrogen is used as fuel. Therefore, it is possible to prevent the use fuel from being switched from hydrogen to gasoline at an early stage when the storage amount of the battery 12 reaches the charge request storage amount without obtaining the chargeable opportunity, thereby increasing the exhaust emission. It can suppress more reliably.

  In the first embodiment, the mixing ratio of the mixed fuel is determined according to the required vehicle power during the fuel switching condition, that is, the target supply power to the motor 17 (required power required for the motor 17). ) To change according to the size of. That is, the mixing ratio changes so that the ratio of gasoline contained in the mixed fuel increases stepwise as the target power supply to the motor 17 increases. As a result, when the target supply power to the motor 17 (required power required for the motor 17) increases while the fuel switching condition is satisfied, the mixing ratio is set to a constant value regardless of the increase in the target supply power. In comparison, the discharge power supplied from the battery 12 to the motor 17 can be reduced.

  That is, as shown in FIG. 7A, for example, when the target supply power to the motor 17 (required power required for the motor 17) increases while the fuel switching condition is satisfied, Assuming that the mixing ratio is a constant value, the generated power of the generator 13 does not change. As a result, the discharge power supplied from the battery 12 to the motor 17 is Pf (kw). Since the ratio of gasoline in the mixed fuel is increased in accordance with the increase in target supply power (required power required for the motor 17), the generated power of the generator 13 is also increased. The supplied discharge power becomes Pe (<Pf) kw smaller than Pf (kw). Accordingly, it is possible to more reliably suppress a decrease in the amount of power stored in the battery 12.

  In the first embodiment, while the fuel switching condition is established, the amount of hydrogen in the mixed fuel is larger than the amount of gasoline, and therefore an increase in exhaust emission can be more reliably suppressed. .

(Embodiment 2)
FIG. 12 shows a second embodiment of the present invention, in which the operation control processing of the engine 11 and the motor 17 in the PCM 6 is different from that of the first embodiment. In the present embodiment, the hardware configuration such as the engine 11 is the same as that of the first embodiment. That is, the PCM 6 is the set storage amount (in the present embodiment, the SOC 42) in which the fuel switching condition is satisfied and the storage amount of the battery 12 is set to be lower than the predetermined storage amount (predetermined amount) and lower than the predetermined storage amount. When it is determined that it is within the above range), the mixing ratio of the mixed fuel is set to a constant value, whereas when it is determined that the charged amount of the battery 12 is less than the set charged amount, the above embodiment is used. 1, the mixing ratio is changed according to the magnitude of the required vehicle power, that is, according to the target supply power to the motor 17 (required power required for the motor 17).

  Next, specific processing operations for the operation control processing of the engine 11 and the motor 17 in the PCM 6 will be described with reference to FIG.

  The first steps SB1 to SB4 are the same as steps SA1 to SA4 in the first embodiment, and thus the description thereof is omitted.

  In step SB5, it is determined whether the fuel used in the engine 11 is hydrogen. If this determination is YES, the process proceeds to step SB6, and if this determination is NO, the process proceeds to step SB13.

In step SB6, it is determined whether or not the target supply power to the motor 17 exceeds the maximum generated power P ₇ (generated power corresponding to the T point in FIG. 6) kw of the generator 13 when hydrogen is used as the fuel. If this determination is YES, the process proceeds to step SB7, and if NO, the process proceeds to step SB15.

  In step SB7, it is determined whether or not the battery storage amount is less than the predetermined storage amount. If this determination is YES, the process proceeds to step SB8, and if NO, the process proceeds to step SB15.

  In step SB8, it is determined whether or not the battery storage amount is equal to or less than the set storage amount. If this determination is YES, the process proceeds to step SB9, and if this determination is NO, the process proceeds to step SB16.

  In step SB9, the fuel used is changed to a mixed fuel of hydrogen and gasoline.

  In step SB10, the target engine speed and the target engine torque are provisionally determined. Specifically, the same processing as step SA9 in the first embodiment is performed.

  In step SB11, the fuel injection amount of hydrogen is determined from the fuel map information described in the first embodiment, based on the target engine speed and the target engine torque provisionally determined in step SB10.

  In step SB12, a target engine torque is determined by adding a predetermined amount of torque to the target engine torque provisionally determined in step SB10 according to the target supply power to the motor 17 (required power required for the motor 17). At the same time, the fuel injection amount of gasoline is determined so that the predetermined amount of torque is added, and the process proceeds to the next step, step SB21 (not shown).

  Specifically, by performing the same processing as in step SA11 of the first embodiment, the mixing ratio of hydrogen and gasoline corresponds to the increase in the required power of the vehicle 1, that is, according to the increase in the target supply power to the motor 17. It increases in steps.

  In step SB13 which proceeds when NO in step SB5, the target engine speed and the target engine torque are determined. Specifically, the same processing as step SA12 of the first embodiment is performed.

  In step SB14, the fuel injection amount of gasoline is determined from the fuel map information based on the target engine speed and target engine torque determined in step SB13, and the process proceeds to the next step, step SB21 (not shown). .

  In step SB15, the target engine speed and the target engine torque are determined. Specifically, the same processing as in step SA14 is performed.

  In step SB16, the fuel injection amount of hydrogen is determined from the fuel map information based on the target engine speed and target engine torque determined in step SB15, and the process proceeds to the next step, step SB21 (not shown). .

  In step SB17, which proceeds to NO in step SB8, the fuel used is changed to a mixed fuel of hydrogen and gasoline.

  In step SB18, the target engine speed and the target engine torque are provisionally determined. Specifically, the same processing as step SA9 in the first embodiment is performed.

  In step SB19, the fuel injection amount of hydrogen is determined based on the target engine speed and the target engine torque provisionally determined in step SB18. Specifically, the same processing as step SA10 of the first embodiment is performed.

  In step SB20, the target engine torque is determined by adding 10% to the target engine torque provisionally determined in step SB18 with the above-mentioned torque additional width set to 10% regardless of the magnitude of the target supply power to the motor 17. .

  Then, the gasoline injection amount is determined so that the additional width of torque is 10%. In other words, the gasoline injection amount is determined such that the ratio of gasoline in the mixed fuel (mixed ratio of the mixed fuel) becomes a constant value regardless of the magnitude of the target supply power.

  Then, after the gasoline injection amount is determined, the process proceeds to the next step, step SB21 (not shown).

  Since the steps after step SB21 are the same as the steps after step SA16 in the first embodiment, description thereof will be omitted.

  As described above, in the second embodiment, the PCM 6 is the set power storage amount that is set to be less than the predetermined power storage amount (predetermined amount) and lower than the predetermined power storage amount while the fuel switching condition is satisfied. When it is determined that it is within the above range (NO in step SB8), the mixing ratio of the mixed fuel is set to a constant value.

  Thereby, for example, in the state where the charged amount of the battery 12 is equal to or less than a predetermined charged amount while the fuel switching condition is satisfied, but does not become less than the set charged amount and has a margin before reaching the charge requested charged amount. (See FIG. 12B) Even if the target supply power to the motor 17 (required power required for the motor 17) increases, the mixing ratio of the mixed fuel is set to a constant value, so that the engine power does not change. The power generated by the generator 13 is also kept constant. As a result, the discharge power from the battery 12 to the motor 17 slightly increases (in the figure, the discharge power increases from Pg (kw) to Ph (kw)), but the ratio of gasoline in the mixed fuel can be kept constant. Therefore, an increase in exhaust emission due to an increase in the proportion of gasoline in the mixed fuel can be reliably suppressed.

  In the second embodiment, when the PCM 6 determines that the charged amount of the battery 12 is less than the set charged amount (when YES in step SB8), the PCM 6 returns to the motor 17 according to the magnitude of the required vehicle power. The ratio of gasoline in the mixed fuel is increased stepwise according to the target supply power (required power required for the motor 17).

  Thereby, for example, when the storage amount of the battery 12 becomes less than the set storage amount while the fuel switching condition is satisfied and approaches the charge request storage amount (see FIG. 12B), the target supply to the motor 17 is achieved. The blending ratio is changed so that the ratio of gasoline in the blended fuel increases as the electric power increases. Therefore, as the target supply power to the motor 17 increases, that is, the generated power of the generator 13 increases as the vehicle required power increases, the discharge power from the battery 12 to the motor 17 decreases (in the figure, discharge). As a result, electric power is reduced from Ph (kw) to Pi (kw). As a result, it is possible to more reliably suppress a decrease in the amount of power stored in the battery 12.

(Embodiment 3)
FIG. 14 shows a third embodiment of the present invention in which the configuration of the vehicle 1 is different from those of the first and second embodiments. In addition, the same code | symbol is attached | subjected about the component substantially the same as FIG. 1, and the detailed description is abbreviate | omitted suitably. That is, the vehicle 1 is a so-called series / parallel hybrid vehicle capable of driving the drive wheels 18 by both the engine 11 and the motor 17.

  Specifically, the vehicle 1 includes an engine 11 coupled to drive wheels 18, a generator 13 as a generator that can be driven by the engine 11, and a battery that is charged with at least power generated by the generator 13. 12, a motor 17 connected to the drive wheel 18 and supplied with electric power from at least one of the generator 13 and the battery 12 to transmit power to the drive wheel 18 together with the engine 11, and charge / discharge power of the battery 12 An inverter / converter 20 (corresponding to the AC-DC converter 20a and the DC-AC converter 20b) that performs conversion control is provided.

  Here, the engine 11 is connected to the drive wheel 18 via a power distribution mechanism 50. The power distribution mechanism 50 is controlled by the PCM 6 to divide the power from the engine 11 to generate the generator 13 and This is transmitted to the drive wheel 18.

  When the required vehicle power required for driving the drive wheels 18 exceeds the power of the engine 11 during the high torque operation, the PCM 6 uses the difference power between the required vehicle power and the engine power. The battery 12 is discharged by outputting a necessary control signal to the battery controller 28 so as to be covered by the power of the motor 17 so that the discharged power can be supplied to the motor 17. Is less than the engine power, the generator 13 is driven with the power of the difference between the vehicle required power and the engine power, and the generated power of the generator 13 is supplied to the battery 12 to charge the battery 12. It is possible.

  The specific control processing of the operation control processing of the engine 11 and the motor 17 in the PCM 6 is not essentially different from the first embodiment and the second embodiment.

  That is, for example, in a situation where the motor is not driven by the power generated by the generator 13, in the flowcharts (FIGS. 8 and 13) showing the first half of the control processing of the PCM 6 in each of the first embodiment and the second embodiment, the motor The target power supplied to the engine 17 may be replaced with the required power of the vehicle, the generated power of the generator 13 may be replaced with the power of the engine 11, and the maximum generated power of the generator 13 may be replaced with the maximum power of the engine 11.

  Further, in the flowchart (FIG. 9) showing the latter half of the control processing of the PCM 6 in the first embodiment and the second embodiment, step SA20, step SA22, and step SA24 may be read as follows.

  That is, in step SA20, all the power of the engine 11 is transmitted to the drive wheels 18.

  In step SA22, the power of the engine 11 and the power of the motor 17 obtained by supplying the discharge power from the battery 12 to the motor 17 are transmitted to the drive wheels 18.

  In step SA24, the power equal to the vehicle required power among the power of the engine 11 is transmitted to the drive wheels 18, and the generator 13 is driven with the surplus power (the difference power between the vehicle required power and the engine power). The power generated by the generator 13 is supplied to the battery 12.

Note that the operation map shown in FIG. 6, the combination efficiency constant line eta _g, thermal efficiency constant line of the eta _h engine 11 eta _g, and eta _h, the electric power supplied to an equal amount of power generation line P (motor 17 of the generator 13 The power (output) of the engine 11 may be referred to as a constant line.

  In the control device for the vehicle 1 (series / parallel hybrid vehicle) provided with the dual fuel engine 11 according to the third embodiment of the present invention configured as described above, the same functions and effects as those of the first and second embodiments. Can be obtained.

(Other embodiments)
The configuration of the present invention is not limited to the above embodiment, but includes various other configurations. That is, in each of the above-described embodiments, when changing the additional width of the torque in accordance with the target supply power to the motor 17 (when executing the process of step SA11 in the first embodiment and step SB12 in the second embodiment), the torque is increased. The additional width is set to increase stepwise in accordance with the increase in the target supply power to the motor 17, but is not limited to this. For example, as shown in FIG. You may set so that it may increase continuously in proportion to the increase in supply electric power.

  Further, in each of the above embodiments, the PCM 6 switches the fuel to be used from the mixed fuel to gasoline and causes the battery controller 28 to charge the battery 12 when the charged amount of the battery 12 falls below the required charging charged amount. However, the present invention is not necessarily limited to this. For example, the ratio of gasoline in the mixed fuel may be further increased to be used fuel. In addition, it is not always necessary to set the charge required storage amount.

  In the first and second embodiments, the vehicle 1 is a series-type hybrid vehicle. In the third embodiment, the vehicle 1 is a series-parallel hybrid vehicle. However, the present invention is not limited to this. For example, the vehicle 1 may be a parallel hybrid vehicle.

  Moreover, in each said embodiment, although alternating current power generated with the generator 13 is once converted into direct-current power with the AC-DC converter 20a, it is not necessarily restricted to this, For example, this The AC-DC converter 20a may be abolished and the AC power generated by the generator 13 may be directly supplied to the motor 17.

  The present invention is useful for a control device of a hybrid vehicle including a dual fuel engine.

It is a figure showing the whole hybrid vehicle composition provided with the dual fuel engine by which the control device concerning the embodiment of the present invention is carried. It is a schematic block diagram which shows the control apparatus of the hybrid vehicle provided with the dual fuel engine. It is a figure which shows the relationship between a throttle opening and the maximum output torque of an engine. It is a driving map of the vehicle when the fuel used for the engine is gasoline. It is the driving | running map of a vehicle when the fuel used for an engine is made into the mixed fuel or hydrogen of gasoline and hydrogen. It is a map which shows an example of the operation line of a dual fuel engine. (A) It is a graph which shows the change of the generated electric power of a generator and the discharge electric power of a battery accompanying the change of the use electric power and the change of the required electric power requested | required of a motor. (B) It is a graph which shows the change of the amount of electrical storage of the battery accompanying the change of use fuel. It is a flowchart which shows the first half part of the operation control process of an engine and a motor in a powertrain control module. It is a flowchart which shows the second half part of the operation control process of an engine and a motor in a powertrain control module. It is a graph which shows the relationship between the target supply electric power to a motor, and a torque addition width | variety. It is a figure which shows the fuel changeover switch displayed on the display of a navigation apparatus. FIG. 8 is a diagram corresponding to FIG. 7 of the second embodiment. FIG. 9 is a diagram corresponding to FIG. 8 of the second embodiment. FIG. 6 is a view corresponding to FIG. FIG. 11 is a view corresponding to FIG. 10 showing another embodiment.

Explanation of symbols

1 Vehicle 6 Powertrain control module (engine operation control means)
(Battery storage amount detection means)
11 Dual fuel engine 12 Battery 13 Generator (generator)
17 Motor 18 Drive wheel 28 Battery controller (battery discharging means)
31 Battery current / voltage sensor (battery storage amount detection means)

Claims (6)

As the fuel to be used, the engine power under the same engine operating conditions is lower than that of the liquid fuel and the liquid fuel, while the gaseous fuel capable of reducing the exhaust emission is mixed with the liquid fuel and the gaseous fuel at a predetermined mixing ratio. A vehicle control device having a dual fuel engine that can be used by switching between the mixed fuel and
A generator that can be driven by the engine;
A battery that is charged with at least power generated from the generator;
A motor coupled to the drive wheels of the vehicle and powered by at least one of the generator and the battery to drive the drive wheels;
Battery storage amount detection means for detecting the storage amount of the battery;
When the required power required for the motor to obtain the required vehicle power required for driving the drive wheels exceeds the generated power of the generator, the required power and the generated power of the generator Battery discharging means capable of discharging the difference power from the battery and supplying it to the motor;
Engine operation control means for performing engine operation control using one of the liquid fuel, the gas fuel, and the mixed fuel as a use fuel, and
The engine operation control means, when performing the engine operation control using the gaseous fuel as the used fuel, the required power exceeds the maximum generated power of the generator obtained by using the gaseous fuel as the used fuel, and When the fuel switching condition in which the battery storage amount detected by the battery storage amount detection means is equal to or less than a predetermined amount is satisfied, the gaseous fuel is used as the used fuel by switching the gaseous fuel from the gaseous fuel to the mixed fuel. Compared to the case where the power of the engine is increased and the power generated by the generator is increased, the power discharged from the battery to the motor by the battery discharging means is reduced. A control device for a vehicle having a dual fuel engine. As the fuel to be used, the engine power under the same engine operating conditions is lower than that of the liquid fuel and the liquid fuel, while the gaseous fuel capable of reducing the exhaust emission is mixed with the liquid fuel and the gaseous fuel at a predetermined mixing ratio. A vehicle control device having a dual fuel engine that can be used by switching between the mixed fuel and
A generator that can be driven by the engine;
A battery that is charged with at least power generated from the generator;
A motor that is coupled to the drive wheels of the vehicle and that is supplied with electric power from the battery and can transmit power to the drive wheels together with the engine;
Battery storage amount detection means for detecting the storage amount of the battery;
When the required vehicle power required for driving the drive wheels exceeds the engine power, the battery is discharged so that the difference power between the required vehicle power and the engine power can be covered by the motor. Battery discharging means capable of supplying discharge power to the motor;
Engine operation control means for performing engine operation control using one of the liquid fuel, the gas fuel, and the mixed fuel as a use fuel, and
When the engine operation control is performed using the gaseous fuel as the fuel, the engine operation control means exceeds the maximum engine power obtained by using the gaseous fuel as the fuel, and the vehicle required power exceeds the battery power storage. When the fuel switching condition in which the stored amount of the battery detected by the amount detecting means is equal to or less than a predetermined amount is satisfied, the fuel used is changed from the gaseous fuel to the mixed fuel, and the gaseous fuel is used as the used fuel. In comparison, the control device for a vehicle having a dual fuel engine, characterized in that the power discharged from the battery to the motor by the battery discharging means is reduced by increasing the power of the engine. . In the control apparatus of the vehicle provided with the dual fuel engine according to claim 1 or 2,
A control apparatus for a vehicle having a dual fuel engine, wherein the mixing ratio of the mixed fuel is configured to change according to the magnitude of the required vehicle power while the fuel switching condition is satisfied. In the control apparatus of the vehicle provided with the dual fuel engine according to claim 1 or 2,
When the fuel switching condition is satisfied and the battery storage amount detected by the battery storage amount detection means is within the range not less than the predetermined amount and not less than the set amount set lower than the predetermined amount, A control apparatus for a vehicle including a dual fuel engine, wherein a mixing ratio of the mixed fuel is a constant value. In the control apparatus of the vehicle provided with the dual fuel engine according to claim 4,
When the fuel switching condition is satisfied and the battery storage amount detected by the battery storage amount detection means is less than the set amount, the mixture ratio of the mixed fuel depends on the magnitude of the vehicle required power. A vehicle control device comprising a dual fuel engine, characterized in that the vehicle is configured to change. In the control apparatus of the vehicle provided with the dual fuel engine according to any one of claims 1 to 5,
A vehicle equipped with a dual fuel engine, wherein a mixing ratio of the mixed fuel is set to a value such that an amount of the gaseous fuel contained in the mixed fuel is larger than an amount of the liquid fuel. Control device.

Images