JP2015202806A - Vehicle control apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control a hybrid vehicle so as to improve fuel economy appropriately.SOLUTION: A vehicle control apparatus includes: first control means for executing mode control to control a travel mode of a hybrid vehicle depending upon whether a charging cost representing a fuel consumption amount of an internal combustion engine required to accumulate a unit power amount of power stored in a rechargeable battery is smaller than an engine cost representing a fuel consumption amount of the internal combustion engine required to output a unit travel output from the vehicle using the power of the engine, not that of a rotary electrical machine; and second control means for executing efficiency control to control the rotary electrical machine and the engine so as to meet a required output and maximize a drive efficiency of an overall drive source constituted by the rotary electrical machine and the engine. Further, in a case where a characteristic required to the vehicle is a characteristic that emphasizes a fuel economy performance, the mode control is performed after the efficiency control is performed.

Description

  The present invention relates to a technical field of a vehicle control device that controls, for example, a hybrid vehicle.

  A hybrid vehicle including both an internal combustion engine and a rotating electric machine is known as a power source for traveling. In such a hybrid vehicle, as disclosed in Patent Document 1 to Patent Document 3, the operating states of the internal combustion engine and the rotating electrical machine are controlled based on the state of the hybrid vehicle.

JP 2013-163495 A JP 2014-004912 A JP2013-141858A

  However, the control methods disclosed in Patent Document 1 to Patent Document 3 described above have a technical problem that the fuel efficiency of the hybrid vehicle cannot always be improved.

  Examples of problems to be solved by the present invention include the above. An object of the present invention is to provide a vehicle control device capable of controlling a hybrid vehicle so as to preferably improve fuel efficiency.

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A vehicle control device that solves the above-described problem is a vehicle control device that controls a hybrid vehicle including an internal combustion engine and a rotating electrical machine that can be charged with a rechargeable battery that can store electric power by being driven using the power of the internal combustion engine. And (i) a charging cost representing a fuel consumption amount of the internal combustion engine required for accumulating a unit amount of electric power accumulated in the rechargeable battery is obtained without using the power of the rotating electrical machine. When the hybrid vehicle travels using the power of the internal combustion engine, the hybrid vehicle is less than the engine cost representing the fuel consumption of the internal combustion engine required to output a unit travel output corresponding to the unit power amount. When the vehicle travel mode is an electric mode in which the vehicle travels without starting the internal combustion engine, and (ii) the charge cost is greater than the engine cost, First control means for performing mode control for controlling the hybrid vehicle such that the mode becomes an engine mode that travels using the power of the internal combustion engine; and satisfying a required output required for the hybrid vehicle and the rotation A second control means for performing efficiency control for controlling the rotating electrical machine and the internal combustion engine so that the drive efficiency of the entire drive source comprising the electrical machine and the internal combustion engine is maximized, and characteristics required for the hybrid vehicle Is a characteristic in which fuel efficiency is more important than running performance, the mode control is performed by the first control unit after the efficiency control is performed by the second control unit.

  The vehicle control device can control a hybrid vehicle including an internal combustion engine and a rotating electric machine. An internal combustion engine can be driven by consuming fuel. The rotating electrical machine can be driven using the power of the internal combustion engine. As a result, the rotating electrical machine can charge the rechargeable battery. That is, the rotating electrical machine can substantially function as a generator.

  The hybrid vehicle can travel in the electric mode. Furthermore, the hybrid vehicle can travel in the engine mode. The “electric mode” is a traveling mode in which the hybrid vehicle travels while maintaining the state where the internal combustion engine is not operating (that is, the internal combustion engine is not driven or the internal combustion engine is not consuming fuel). is there. In this case, the hybrid vehicle may travel using, for example, the power of a rotating electrical machine different from the rotating electrical machine that functions as a generator or the power of a rotating electrical machine that functions as a generator. The “engine mode” is a traveling mode in which traveling is performed using the power of the internal combustion engine.

  In order to control such a hybrid vehicle (in particular, to switch the travel mode of the hybrid vehicle), the vehicle control device includes first control means.

  The first control means performs mode control for determining the travel mode of the hybrid vehicle according to the magnitude relationship between the charging cost and the engine cost. Specifically, when the charging cost is lower than the engine cost, the first control means performs mode control for controlling the hybrid vehicle so that the traveling mode of the hybrid vehicle becomes the electric mode. On the other hand, the first control means performs mode control for controlling the hybrid vehicle so that the travel mode of the hybrid vehicle becomes the engine mode when the engine cost is lower than the charging cost.

  Here, the “charging cost” directly or indirectly represents the fuel consumption of the internal combustion engine required to store the unit power amount of the power stored in the rechargeable battery (in other words, the total power). It is an index value. In other words, the “charging cost” directly or indirectly represents the fuel consumption of the internal combustion engine required to store the power of the unit power amount among the power (total power) stored in the rechargeable battery. It is an index value. Furthermore, in other words, “charging cost” means “fuel consumption of the internal combustion engine per unit of electric energy required to store electric power (total electric power) stored in the rechargeable battery at the time when the charging cost is calculated. "Is an index value that directly or indirectly represents" ". That is, the “charging cost” is not an index value simply representing the fuel consumption of the internal combustion engine required to store the electric power (total electric power) stored in the rechargeable battery, but the electric power stored in the rechargeable battery. An index that directly or indirectly represents the amount of fuel consumed by the internal combustion engine required to store the power as the amount of fuel consumed to store the power of the unit power (that is, a numerical value per unit of power) Value. For example, the total amount of power stored in the rechargeable battery is “X1”, and the fuel consumption of the internal combustion engine required to store the power of “X1” stored in the rechargeable battery is “Y1”. In this case, the charging cost may be an index value that directly or indirectly represents a numerical value of “Y1 (that is, fuel consumption) / X1 (that is, total amount of power)”.

  On the other hand, the “engine cost” directly represents the fuel consumption of the internal combustion engine required for the hybrid vehicle to output a unit travel output corresponding to the unit power amount using the power of the internal combustion engine without using the power of the rotating electrical machine. It is an index value that is indicated either indirectly or indirectly. In other words, the “engine cost” is assumed to be a “unit” that is estimated to be required for the hybrid vehicle to travel using the power of the internal combustion engine without using the power of the rotating electrical machine when the engine cost is calculated. This is an index value that directly or indirectly indicates “fuel consumption of the internal combustion engine per driving output”. For example, the unit travel output corresponding to the unit power amount is “X2”, and the fuel consumption amount of the internal combustion engine that is estimated to be required for the hybrid vehicle to output the travel output of “X2” is “ In the case of “Y2”, the engine cost may be an index value that directly or indirectly represents a numerical value “Y2 (ie, fuel consumption) / X2 (ie, travel output)”. Alternatively, for example, the travel output required for the hybrid vehicle is “X3”, and the fuel consumption of the internal combustion engine that is estimated to be required for the hybrid vehicle to output the travel output of “X3” from now on. Is “Y3”, the engine cost may be an index value that directly or indirectly represents a numerical value “Y3 (ie, fuel consumption) / X3 (ie, travel output)”. .

  Here, considering that the charging cost represents the fuel consumption of the internal combustion engine required to store the power of the unit electric energy stored in the rechargeable battery, the charging cost is substantially It can also be said that it represents the fuel consumption of the internal combustion engine required for the hybrid vehicle to output the unit travel output using the power of the rotating electrical machine that is driven using the electric power stored in the rechargeable battery. That is, it can be said that the charging cost represents the fuel consumption of the internal combustion engine required for the hybrid vehicle to output the unit travel output in the electric mode. On the other hand, the engine cost can be said to represent the fuel consumption of the internal combustion engine that is required for the hybrid vehicle to output the unit travel output using the power of the internal combustion engine. That is, it can be said that the engine cost represents the fuel consumption of the internal combustion engine required for the hybrid vehicle to output the unit travel output in the engine mode. Then, if it is determined that the charging cost is lower than the engine cost, the fuel consumption required to output the unit travel output using the power of the rotating electrical machine that is driven using the electric power stored in the rechargeable battery Is less than the fuel consumption required to output the unit travel output using the power of the internal combustion engine driven by consuming the fuel. That is, when it is determined that the charging cost is lower than the engine cost, the fuel consumption of the hybrid vehicle that outputs the unit travel output in the electric mode is the fuel consumption of the hybrid vehicle that outputs the unit travel output in the engine mode. Less than. On the other hand, if it is determined that the charging cost is higher than the engine cost, the fuel consumption required to output the unit travel output using the power of the internal combustion engine that consumes and drives the fuel is charged to the rechargeable battery. This is less than the fuel consumption required to output the unit travel output using the power of the rotating electrical machine driven using the stored electric power. That is, when it is determined that the charging cost is larger than the engine cost, the fuel consumption of the hybrid vehicle that outputs the unit travel output in the engine mode is the fuel consumption of the hybrid vehicle that outputs the unit travel output in the electric mode. Less than.

  In consideration of the relationship between the magnitude relationship between the charging cost and the engine cost and the magnitude relationship between the fuel consumptions required to output the unit travel output, the control means determines that the travel mode of the hybrid vehicle has the unit travel output. It can be said that the hybrid vehicle is controlled so as to achieve a desired travel mode in which the fuel consumption required for output is reduced. That is, it can be said that the control means controls the hybrid vehicle so that the traveling mode of the hybrid vehicle becomes a desired traveling mode in which the fuel consumption required for traveling of the hybrid vehicle is reduced.

  In particular, since the charging cost represents fuel consumption per unit electric energy, the charging cost reflects the driving efficiency (for example, thermal efficiency) of the internal combustion engine driven to store electric power in the rechargeable battery. Yes. Specifically, depending on the driving efficiency of the internal combustion engine, even when the same amount of power is stored in the rechargeable battery, the fuel consumption required to store the power is not always the same. Absent. Similarly, depending on the driving efficiency of the internal combustion engine, even when electric power is accumulated in the rechargeable battery due to consumption of the same amount of fuel, the total amount of accumulated electric power is not always the same. That is, depending on the driving efficiency of the internal combustion engine, the value of the electric power stored in the rechargeable battery is not always the same. Thus, even if the value of electric power is not necessarily the same, the charging cost depends on the total amount of electric power stored in the rechargeable battery and the fuel consumption required for the electric power storage ( For example, it can be said that the value of electric power is appropriately represented because it fluctuates (according to the driving efficiency of the internal combustion engine when electric power is accumulated). For this reason, the vehicle control device considers the value of the electric power stored in the rechargeable battery (in other words, the driving efficiency of the internal combustion engine driven to store the electric power in the rechargeable battery), and then the driving mode of the hybrid vehicle. However, it is possible to control the hybrid vehicle so as to achieve a desired travel mode in which the fuel consumption required for outputting the unit travel output is reduced.

  A reduction in fuel consumption required to output the unit travel output leads to an improvement in the fuel consumption of the hybrid vehicle (particularly, the fuel consumption when viewed as a whole travel of the hybrid vehicle). Therefore, the vehicle control device can control the hybrid vehicle so as to be in a desired travel mode in which fuel efficiency is good. That is, the vehicle control device can control the hybrid vehicle so as to improve the fuel efficiency.

  Furthermore, the vehicle control device takes into account the charging cost for all the power stored in the rechargeable battery, and the fuel consumption required for the driving mode of the hybrid vehicle to output the unit driving output is small. The hybrid vehicle can be controlled so that the desired traveling mode is obtained. That is, the vehicle control device takes into consideration not only the charging cost for only the newly accumulated power in the rechargeable battery but also the charging cost for the power already accumulated in the rechargeable battery, The hybrid vehicle can be controlled so that a desired travel mode is achieved in which the amount of fuel consumed to output the unit travel output is reduced. In other words, the vehicle control device performs charging for all the power stored in the rechargeable battery instead of the magnitude relationship between the charging cost and the engine cost only for the power newly stored in the rechargeable battery. The hybrid vehicle is controlled based on the magnitude relationship between the cost and the engine cost. Accordingly, the travel mode of the hybrid vehicle is a travel mode in which the amount of fuel consumption required to output the unit travel output is reduced (that is, the fuel efficiency is improved). Therefore, the vehicle control apparatus can control the hybrid vehicle so as to reduce the fuel consumption required to output the unit travel output (that is, to improve the fuel efficiency suitably).

  The vehicle control device further includes second control means in addition to the first control means. The second control means performs efficiency control for controlling the rotating electrical machine and the internal combustion engine so as to satisfy a required output required for the hybrid vehicle.

  In particular, the second control means performs efficiency control for controlling the rotary electric machine and the internal combustion engine so that the drive efficiency of the entire drive source including the rotary electric machine and the internal combustion engine is maximized. For example, the drive efficiency of the entire drive source composed of the rotating electrical machine and the internal combustion engine may be a drive efficiency obtained by multiplying the drive efficiency of the rotary electrical machine and the drive efficiency of the internal combustion engine. In this case, the second control means performs efficiency control for controlling the rotary electric machine and the internal combustion engine so that the drive efficiency obtained by multiplying the drive efficiency of the rotary electric machine and the drive efficiency of the internal combustion engine is maximized. Also good.

  Here, for example, in a hybrid vehicle, the rotating electrical machine and the internal combustion engine are often controlled so that the drive efficiency of the internal combustion engine is maximized. However, when the rotating electrical machine and the internal combustion engine are controlled so that the driving efficiency of the internal combustion engine is maximized, the driving efficiency of the rotating electrical machine may not be maximized or improved. For example, when the hybrid vehicle is traveling at a relatively high vehicle speed and the rotational speed of the internal combustion engine is relatively low (that is, the output is relatively low), the rotating electrical machine that is driven using the power of the engine The driving efficiency may not be good. In this case, although the driving efficiency of the rotating electrical machine is improved by adjusting the output of the rotating electrical machine, there is a possibility that the driving efficiency of the internal combustion engine may deteriorate due to the adjustment of the output of the rotating electrical machine. However, the vehicle control device includes the rotating electrical machine and the internal combustion engine even when the driving efficiency of the internal combustion engine deteriorates while the driving efficiency of the rotating electrical machine is improved by adjusting the output of the rotating electrical machine. The rotating electrical machine and the internal combustion engine can be controlled so that the drive efficiency of the entire drive source is maximized. Therefore, the vehicle control apparatus can arbitrarily increase / decrease the output of the rotating electrical machine or arbitrarily increase / decrease the output of the internal combustion engine while maintaining the drive efficiency of the entire drive source at a maximum. As a result, the vehicle control device does not cause a serious deterioration in the fuel consumption of the hybrid vehicle compared to the case where the rotating electric machine and the internal combustion engine are controlled so that the drive efficiency of the internal combustion engine is always maximized. Drive efficiency can be improved. Therefore, the rotating electrical machine can be driven so that the charging operation of the rechargeable battery is performed efficiently without extremely deteriorating the fuel consumption of the hybrid vehicle.

  In particular, the vehicle control device performs mode control by the first control means after performing the efficiency control by the second control means when the characteristic required for the hybrid vehicle is a characteristic in which fuel efficiency is more important than the driving performance. I do. As a result of the efficiency control by the second control means, the rotating electrical machine is likely to be able to be driven with relatively good driving efficiency as compared with the case where the efficiency control by the second control means is not performed. This is as described above. That is, as a result of performing the efficiency control by the second control means, there is a high possibility that the charging cost is relatively reduced. When the charging cost is relatively small, the frequency at which it is determined that the charging cost is smaller than the engine cost increases. That is, when the charging cost is relatively low, the frequency of the hybrid vehicle traveling in the electric mode is relatively high. As a result, the fuel efficiency of the hybrid vehicle is improved. As described above, the vehicle control device suitably improves the fuel consumption by performing the mode control by the first control unit after the charging cost is relatively reduced by performing the efficiency control by the second control unit. The hybrid vehicle can be controlled.

  These effects and other advantages of the present invention will be further clarified from the embodiments described below.

It is a block diagram which shows an example of a structure of the hybrid vehicle of this embodiment. It is a flowchart which shows an example of the flow of operation | movement (especially operation | movement which controls each operating point of an engine and a motor generator) of the hybrid vehicle of this embodiment. It is a flowchart which shows an example of the flow of operation | movement of the hybrid vehicle of this embodiment (especially operation | movement which controls the driving mode of a hybrid vehicle). It is an alignment chart of a motor generator and an engine. 4 is a map showing a relationship between the engine operating point and the engine efficiency, and a map showing a relationship between the motor generator operating point and the MG1 efficiency.

  Hereinafter, an embodiment of a vehicle control device of the present invention will be described with reference to the drawings. In the following, description will be given using the hybrid vehicle 10 to which the embodiment of the vehicle control device of the present invention is applied.

(1) Configuration of Hybrid Vehicle First, the configuration of the hybrid vehicle 10 of the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing an example of the configuration of the hybrid vehicle 10 of the present embodiment.

  As shown in FIG. 1, the hybrid vehicle 10 is a specific example of an axle 11, wheels 12, an ECU (Electronic Control Unit) 100 that is a specific example of a “vehicle control device”, and a “internal combustion engine”. Engine ENG, motor generator MG1 which is a specific example of “rotating electric machine”, motor generator MG2, power split mechanism 300, inverter 400, and battery 500 which is a specific example of “storage battery”.

  The axle 11 is a transmission shaft for transmitting the power output from the engine ENG and the motor generator MG2 to the wheels. The wheel 12 is means for transmitting power transmitted via an axle 11 described later to the road surface.

  The ECU 100 is an electronic control unit configured to be able to control the entire operation of the hybrid vehicle 10. Particularly in the present embodiment, the ECU 100 includes a driving mode control unit 101, which is a specific example of “first control means”, and a fuel consumption rate calculation unit 102 as logical or physical processing blocks realized therein. And a fuel consumption rate comparison unit 103 and an operating point control unit 104 which is a specific example of “second control means”.

  The travel mode control unit 101 controls the travel mode of the hybrid vehicle 10. Specifically, the travel mode control unit 101 controls the hybrid vehicle 10 so that the travel mode of the hybrid vehicle 10 becomes a desired travel mode. For example, the travel mode control unit 101 may control the hybrid vehicle 10 so that the travel mode of the hybrid vehicle 10 is an HV (Hybrid Vehicle) mode in which the vehicle travels using the power of the engine ENG. For example, traveling mode control unit 101 sets the traveling mode of hybrid vehicle 10 to an EV (Electric Vehicle) mode in which traveling is performed using at least one power of motor generator MG1 and motor generator MG2 without operating engine ENG. In addition, the hybrid vehicle 10 may be controlled.

  In the EV mode, the engine ENG is not operating (in other words, the engine ENG is not driven, in other words, the engine ENG is not consuming fuel). For this reason, the fuel efficiency of the hybrid vehicle 10 improves as the traveling frequency in the EV mode increases.

  Particularly in the present embodiment, the travel mode control unit 101 controls the hybrid vehicle 10 so that the travel mode of the hybrid vehicle 10 becomes a travel mode determined based on the comparison result of the fuel consumption rate comparison unit 103. The travel mode determined based on the comparison result of the fuel consumption rate comparison unit 103 will be described in detail later (see FIG. 3 and the like).

  The fuel consumption rate calculation unit 102 determines a fuel consumption rate to be compared by the fuel consumption rate comparison unit 103 (specifically, a battery fuel consumption rate F and a running engine fuel consumption rate, which will be described later), when the driving mode of the hybrid vehicle 10 is determined. H) is calculated. The details of the calculation method of the battery fuel consumption rate F and the running engine fuel consumption rate H by the fuel consumption rate calculation unit 102 will be described in detail later (see FIG. 2 and the like).

  The fuel consumption rate comparison unit 103 compares the battery fuel consumption rate F calculated by the fuel consumption rate calculation unit 102 with the running engine fuel consumption rate H. Specifically, the fuel consumption rate comparison unit 103 determines the magnitude relationship between the battery fuel consumption rate F and the running engine fuel consumption rate H. The fuel consumption rate comparison unit 103 transmits the comparison result (that is, the determination result of the magnitude relationship) to the travel mode control unit 101.

  The operating point control unit 104 controls the operating point of the engine ENG and the operating point of the motor generator MG1. For example, the operating point control unit 104 may control the operating point of the engine ENG by controlling at least one of the rotational speed and torque of the engine ENG. For example, the operating point control unit 104 may control the operating point of the motor generator MG1 by controlling at least one of the rotation speed and torque of the motor generator MG1. Particularly in the present embodiment, the operating point control unit 104 multiplies the drive efficiency of the engine ENG (hereinafter referred to as “engine efficiency” as appropriate) and the drive efficiency of the motor generator MG1 (hereinafter referred to as “MG1 efficiency” as appropriate). Each of the operating point of engine ENG and the operating point of motor generator MG1 is controlled so that the parameter obtained by the combination is maximized. The operation of controlling the operating point of engine ENG and the operating point of motor generator MG1 by operating point control unit 104 will be described in detail later (see FIG. 2 and the like).

  The engine ENG is driven by burning fuel such as gasoline or light oil. The engine ENG functions as a main power source of the hybrid vehicle 10. In addition, engine ENG functions as a power source for rotating (in other words, driving) a rotation shaft of motor generator MG1 described later.

  Motor generator MG1 functions as a generator for charging battery 500. When motor generator MG1 functions as a generator, the rotation shaft of motor generator MG1 is rotated by the power of engine ENG. However, motor generator MG <b> 1 may function as an electric motor that supplies power of hybrid vehicle 10 by being driven using electric power stored in battery 500.

  Motor generator MG <b> 2 functions as an electric motor that supplies power of hybrid vehicle 10 by being driven using electric power stored in battery 500. In addition, motor generator MG2 may function as a generator for charging battery 500. When motor generator MG2 functions as a generator, the rotation shaft of motor generator MG2 is rotated by the power transmitted from axle 11 to motor generator MG2.

  The power split mechanism 300 is a planetary gear mechanism including a sun gear, a planetary carrier, a pinion gear, and a ring gear (not shown). The rotation shaft of the sun gear is connected to the rotation shaft of motor generator MG1. The rotation shaft of the ring gear is connected to the rotation shaft of motor generator MG2. The rotating shaft of the planetary carrier located between the sun gear and the ring gear is connected to the rotating shaft (that is, the crankshaft) of the engine ENG. The rotation of the engine ENG is transmitted to the sun gear and the ring gear by the planetary carrier and the pinion gear. That is, the power of the engine ENG is divided into two systems. In the hybrid vehicle 10, the rotating shaft of the ring gear is connected to the axle 11 in the hybrid vehicle 10, and the driving force is transmitted to the wheels 12 through the axle 11.

  Inverter 400 converts the DC power extracted from battery 500 into AC power and supplies it to motor generator MG1 and motor generator MG2. Further, inverter 400 converts AC power generated by motor generator MG1 and motor generator MG2 into DC power and supplies it to battery 500. The inverter 400 may be configured as a part of a so-called PCU (Power Control Unit).

  Battery 500 is a power supply source that supplies electric power for driving motor generator MG1 and motor generator MG2 to motor generator MG1 and motor generator MG2. The battery 500 is a rechargeable storage battery.

(2) Operation of Hybrid Vehicle 10 Subsequently, referring to FIG. 2 and FIG. 3, the operation of the hybrid vehicle 10 (particularly, after the respective operating points of the engine ENG and the motor generator MG1 are controlled) The operation for controlling the mode will be described. FIG. 2 is a flowchart showing an example of the flow of the operation of hybrid vehicle 10 (particularly, the operation for controlling the operating points of engine ENG and motor generator MG1). FIG. 3 is a flowchart showing an example of the flow of the operation of the hybrid vehicle 10 (particularly, the operation for controlling the travel mode of the hybrid vehicle 10).

  As shown in FIG. 2, the operating point control unit 104 determines whether or not the MG1 efficiency is smaller than the first threshold (step S41). The determination in step S41 is mainly a determination of whether or not the MG1 efficiency is small (or whether or not the MG1 efficiency has deteriorated) so that it is preferable to adjust the operating point of the motor generator MG1 in order to improve the MG1 efficiency. It is. For this reason, an appropriate value determined according to the specification of the hybrid vehicle 10 from the viewpoint of whether or not it is preferable to adjust the operating point of the motor generator MG1 to improve the MG1 efficiency is used as the first threshold value. preferable.

  The MG1 efficiency is an index value that represents the ratio of the total amount of energy output by the motor generator MG1 to the total amount of energy input to the motor generator MG1. For example, as described above, when motor generator MG1 functions as a generator, motor generator MG1 is driven using the power of engine ENG. Therefore, in this case, the MG1 drive efficiency is the ratio of the total amount of energy generated by the motor generator MG1 using the energy input from the engine ENG to the total amount of energy input from the engine ENG to the motor generator MG1. The index value to represent may be sufficient. In other words, MG1 power generation efficiency P may be an index value that represents a ratio of the total amount of power output from motor generator MG1 as a result of power generation to the total amount of energy input to motor generator MG1 for power generation. .

  The operating point control unit 104 refers to a map representing the correspondence relationship between the operating point of the motor generator MG1 (for example, the operating point specified by the torque of the motor generator MG1 and the rotational speed of the motor generator MG1) and the MG1 efficiency. It is preferable to calculate the MG1 efficiency.

  As a result of the determination in step S41, when it is determined that the MG1 efficiency is smaller than the first threshold (step S41: Yes), it is preferable to adjust the operating point of the motor generator MG1 in order to improve the MG1 efficiency. Therefore, the operating point control unit 104 controls the operating points of the engine ENG and the motor generator MG1 in order to improve the MG1 efficiency. However, when the SOC (State Of Charge) of the battery 500 is excessively small, it is preferable that the battery 500 is preferentially charged (typically, fast charging). Therefore, the operating point control unit 104 first determines whether or not the SOC of the battery 500 is smaller than a predetermined second threshold value (step S42).

  As a result of the determination in step S42, when it is determined that the SOC of the battery 500 is not smaller than the second threshold value (step S43: No), the operating point control unit 104 increases the engine ENG in order to improve the MG1 efficiency. And each operating point of motor generator MG1 is controlled (step S42).

  Here, with reference to FIG. 4 and FIG. 5, the operation of “controlling the respective operating points of the engine ENG and the motor generator MG1 to improve the MG1 efficiency” shown in step S42 of FIG. 2 will be described in more detail. . FIG. 4 is a collinear diagram of motor generators MG1 and MG2 and engine ENG. FIG. 5 is a map showing the relationship between the operating point of engine ENG and engine efficiency, and a map showing the relationship between the operating point of motor generator MG1 and MG1 efficiency. In the following, for the sake of simplification of explanation, the hybrid vehicle 10 running at a relatively high vehicle speed in a state where the rotational speed of the engine ENG is relatively low (that is, the output is relatively low) is taken as an example. Will be described.

  As shown by the thick line in FIG. 4, the hybrid vehicle 10 is traveling at a relatively high vehicle speed (see the uppermost graph in FIG. 4), and the engine ENG has a relatively low rotational speed (the middle stage in FIG. 4). In the case of the operating point E1 in the graph), the rotational speed of the motor generator MG1 is relatively low and the torque of the motor generator MG1 is relatively high (see the operating point M1 in the lowermost graph of FIG. 4). . In this case, as shown in FIG. 5, the MG1 efficiency is relatively low. As a result, when motor generator MG1 functions as a generator, motor generator MG1 generates power with a relatively poor MG1 efficiency.

  Thus, as one method for improving the MG1 efficiency, a method of increasing the rotation speed (or output) of the motor generator MG1 as shown in FIG. However, although the MG1 efficiency is increased by increasing the rotation speed of the motor generator MG1, the increase in the rotation speed of the motor generator MG1 leads to a change in the operating point of the engine ENG. For example, as shown in FIG. 4, when the operating point of motor generator MG1 is shifted from M1 to M2 due to an increase in the rotational speed of motor generator MG1, the operating point of engine ENG is shifted from E1 to E2. As a result, as shown in FIG. 5B, although the MG1 efficiency is increased by increasing the rotation speed of the motor generator MG1, the engine efficiency may be deteriorated.

  In particular, as the SOC of the battery 500 decreases, the total amount of power to be input to the battery 500 increases. Therefore, the output (for example, the rotational speed) of the motor generator MG1 that is driven to charge the battery 500 further increases. There is a tendency. Therefore, as the SOC of the battery 500 decreases, the rotational speed of the engine ENG also tends to increase further. As a result, the engine efficiency may be further deteriorated.

  In view of such a situation, in the present embodiment, the operating point control unit 104 controls the operating points of the engine ENG and the motor generator MG1 in the following manner in order to improve the MG1 efficiency (in other words, adjustment) Or change).

  Specifically, considering that it is preferable to increase the output (for example, the rotational speed) of the motor generator MG1 in order to increase the MG1 efficiency, the operating point control unit 104 determines the motor generator MG1 and the engine ENG. The operating points of the motor generator MG1 and the engine ENG are controlled so that the output (for example, the rotational speed) increases.

  At this time, it goes without saying that the operating point control unit 104 controls the operating points of the engine ENG and the motor generator MG1 so that the required output required for the hybrid vehicle 10 is satisfied. That is, it goes without saying that the operating point control unit 104 controls the operating points of the engine ENG and the motor generator MG1 so that the output of the engine ENG + the output of the motor generator MG1 = the required output.

  Further, at this time, the operating point control unit 104 sets each parameter of the engine ENG and the motor generator MG1 so that the parameter (that is, MG1 efficiency × engine efficiency) obtained by multiplying the MG1 efficiency and the engine efficiency is maximized. Control the operating point. In other words, the operating point control unit 104 sets each of the engine ENG and the motor generator MG1 so that the drive efficiency of the single drive source is maximized when the motor generator MG1 and the engine ENG are regarded as a single drive source. Control the operating point. As a result, increasing the number of revolutions of the motor generator MG1 may increase the MG1 efficiency, while the engine efficiency may deteriorate. However, the efficiency of the hybrid vehicle 10 as a whole is extremely deteriorated. Little or no. Therefore, motor generator MG1 can generate electric power with a relatively good MG1 efficiency.

  The operating point control unit 104 controls the operating points of the engine ENG and the motor generator MG1 so that the parameter obtained by multiplying the MG1 efficiency and the engine efficiency is maximized. The operating points of engine ENG and motor generator MG1 may be controlled such that becomes equal to or higher than the first predetermined value and engine efficiency equals or exceeds the second predetermined value. For example, the operating point control unit 104 may control the operating points of the engine ENG and the motor generator MG1 so that the MG1 efficiency is 90% or higher and the engine efficiency is 38% or higher. Thereafter, the operation shown in FIG. 3 (specifically, the operation continued from # 1 in FIG. 3) is performed.

  In FIG. 2 again, on the other hand, when it is determined that the SOC of the battery 500 is smaller than the second threshold value as a result of the determination in step S42 (step S42: Yes), the operating point control unit 104 The operating points of engine ENG and motor generator MG1 are controlled so as to be charged (typically, fast charging) (step S43). For example, the operating point control unit 104 may control the operating points of the engine ENG and the motor generator MG1 so that the output of the engine ENG becomes a certain value or more. Thereafter, the operation shown in FIG. 3 (specifically, the operation continued from # 1 in FIG. 3) is performed.

  On the other hand, as a result of the determination in step S41, when it is determined that the MG1 efficiency is not smaller than the first threshold value (step S41: No), the operating point control unit 104 performs the engine in the manner shown in step S42 or step S43. It is not necessary to control the operating points of ENG and motor generator MG1. In this case, the operating point control unit 104 may control the operating points of the engine ENG and the motor generator MG1 so that the engine efficiency is maximized. Thereafter, the operation shown in FIG. 3 (specifically, the operation continued from # 1 in FIG. 3) is performed.

  Thereafter, as shown in FIG. 3, the fuel consumption rate calculation unit 102 sets initial values of the battery fuel consumption rate F, the battery power integration amount a, and the battery fuel consumption amount J (step S11). Hereinafter, the battery fuel consumption rate F, the battery power integration amount a, and the battery fuel consumption amount J will be described in order. The battery fuel consumption rate F corresponds to a specific example of “charging cost”.

  The battery fuel consumption rate F is an index value that represents the fuel consumption amount of the engine ENG per unit electric energy required for accumulating the electric power (total electric power) accumulated in the battery 500. In other words, the battery fuel consumption rate F represents the fuel consumption amount of the engine ENG that is required to store the unit power amount of the electric power stored in the battery 500. In other words, the battery fuel consumption rate F represents the fuel consumption amount of the engine ENG that is required to store the power of the unit power amount when the power stored in the battery 500 is stored. For example, an amount of electric power “X4 (where X is 0 or more)” is stored in the battery 500, and an amount of fuel “Y4” is stored by the engine ENG in order to store this amount of electric power “X4”. When consumed, the battery fuel consumption rate F may be an index value representing a numerical value specified by the mathematical expression “Y4 / X3”. In the following, for convenience of explanation, the description will be made assuming that the unit of the battery fuel consumption rate F is “g / kWh”.

  The fuel consumption rate calculation unit 102 may set an arbitrary fixed value predetermined for each vehicle type or specification of the hybrid vehicle 10 as an initial value of the battery fuel consumption rate F. In this case, as a fixed value, a battery fuel consumption rate (for example, 280 g / kWh) calculated from a simulation when it is assumed that the hybrid vehicle 10 has traveled on a specific travel route may be employed. Alternatively, the fuel consumption rate calculation unit 102 may set the battery fuel consumption rate F at the time when the operation shown in FIG.

  The battery power integration amount a represents the total amount of power stored in the battery 500. For example, the battery power integration amount a may correspond to a value calculated by multiplying the total amount of power that can be stored in the battery 500 by the actual SOC when the SOC becomes 100%. In the following description, for convenience of explanation, the description will be made assuming that the unit of the battery power integrated amount a is “kWh”.

  The fuel consumption rate calculation unit 102 may set a fixed value corresponding to the amount of power stored in the battery 500 as the initial value of the battery power integration amount a when the SOC becomes a constant value. Alternatively, the fuel consumption rate calculation unit 102 may set the battery power integrated amount a at the time when the operation shown in FIG. 2 is completed last time as the initial value of the battery power integrated amount a. Alternatively, the fuel consumption rate calculation unit 102 calculates or estimates the total amount of power stored in the battery 500 by referring to the SOC output from the SOC sensor (not shown), and calculates the total amount of power calculated or estimated. The battery power integrated amount a may be set to an initial value.

  The battery fuel consumption amount J is an index value that represents the fuel consumption amount (in other words, the total amount) of the engine ENG required to store the electric power (total electric power) stored in the battery 500. The battery fuel consumption amount J is calculated from a mathematical expression of battery fuel efficiency F × battery power integration amount a. Therefore, the fuel consumption rate calculation unit 102 is a value calculated by multiplying the initial value of the battery fuel consumption rate F set in the above-described manner by the initial value of the battery fuel consumption rate F set in the above-described manner. May be set to the initial value of the battery fuel consumption amount J. In the following description, for convenience of explanation, it is assumed that the unit of the battery fuel consumption J is “g”.

  Thereafter, the fuel consumption rate calculation unit 102 determines whether or not the battery 500 is newly charged (that is, whether or not power is newly input to the battery 500) (step S22).

  As a result of the determination in step S22, when it is determined that the battery 500 is newly charged (that is, power is newly input to the battery 500) (step S22: Yes), the fuel consumption rate calculation unit 102 The battery fuel consumption rate F ′ after the battery 500 is newly charged is calculated (step S23).

  Specifically, the fuel consumption rate calculation unit 102 calculates the battery power integration amount a ′ after the battery 500 is newly charged (step S23). When the battery 500 is newly charged, the battery power integrated amount a ′ is greater than the battery power integrated amount a before the battery 500 is newly charged. (Hereinafter referred to as “battery input power amount d”) should increase. Therefore, the fuel consumption rate calculation unit 102 calculates the battery power integration amount a ′ by adding the battery input power amount d to the battery power integration amount a. That is, the fuel consumption rate calculation unit 102 calculates the battery power integration amount a ′ using the mathematical formula: battery power integration amount a ′ = battery power integration amount a + battery input power amount d.

  In addition, the fuel consumption rate calculation unit 102 calculates the battery fuel consumption J 'after the battery 500 is newly charged (step S23). When the battery 500 is newly charged, the battery fuel consumption amount J ′ is stored in the battery input power amount d more than the battery fuel consumption amount J before the battery 500 is newly charged. The required fuel consumption amount J of the engine ENG should be increased (hereinafter referred to as “battery input fuel consumption amount j1”). Therefore, the fuel consumption rate calculation unit 102 calculates the battery input fuel consumption amount j1 and calculates the battery fuel consumption amount J ′ by adding the calculated battery input fuel consumption amount j1 to the battery fuel consumption amount J. . That is, the fuel consumption rate calculation unit 102 calculates the battery fuel consumption amount J ′ by using the mathematical formula: battery fuel consumption amount J ′ = battery fuel consumption amount J + battery input fuel consumption amount j1.

  The fuel consumption rate calculation unit 102 may calculate the battery input fuel consumption amount j1 using a mathematical formula: battery input fuel consumption amount j1 = power generation engine fuel consumption rate G × correction coefficient α × battery input power amount d.

  The engine fuel consumption rate G during power generation is an index value representing the fuel consumption amount of the engine ENG per unit power amount required for newly storing the battery input power amount d in the battery 500. In other words, the engine fuel consumption rate G during power generation represents the fuel consumption of the engine ENG that is required to accumulate the unit power amount of the battery input power amount d in the battery 500. In other words, the engine fuel consumption rate G during power generation is the fuel consumption of the engine ENG required to store the unit power amount in the battery 500 when the battery input power amount d is newly stored in the battery 500. Represents an amount. For example, when an amount of fuel “Y5” is consumed by the engine ENG in order to store the electric power of the battery input electric energy d, the engine fuel consumption rate G during generation is specified by an equation “Y5 / d”. It may be an index value representing a numerical value. In the following, for convenience of explanation, the description will be made assuming that the unit of the power generation engine fuel consumption rate G is “g / kWh”.

  The fuel consumption rate calculation unit 102 refers to a map representing a correspondence relationship between the operating point of the engine ENG (for example, the operating point specified by the torque of the engine ENG and the engine speed) and the engine fuel consumption rate, thereby generating power. It is preferable to calculate the hour engine fuel efficiency G.

  The battery 500 is typically newly charged when the motor generator MG1 functions as a generator. In this case, engine ENG functions as a power source for rotating (in other words, driving) the rotation shaft of motor generator MG1. Therefore, when the motor generator MG1 functions as a generator, the fuel consumption rate calculation unit 102 preferably calculates the engine fuel consumption rate G during power generation.

  On the other hand, battery 500 may be newly charged when motor generator MG2 functions as a generator. That is, the battery 500 may be newly charged by so-called regenerative power generation. In this case, engine ENG does not function as a power source for rotating (in other words, driving) the rotation shaft of motor generator MG2. When motor generator MG2 functions as a generator, the fuel consumption amount of engine ENG required for newly storing battery input power amount d in battery 500 is zero. Therefore, when the motor generator MG2 functions as a generator, the fuel consumption rate calculation unit 102 preferably sets the engine fuel consumption rate G during power generation to 0 [g / kWh].

  The correction coefficient α is multiplied by the reciprocal of the power generation efficiency P of the motor generator MG1 (hereinafter referred to as “MG1 power generation efficiency P”) and the reciprocal of the charging efficiency Q of the battery 500 (hereinafter referred to as “battery charging efficiency Q”). It is an index value calculated by combining them.

  MG1 power generation efficiency P is always 100% (that is, all energy input from engine ENG to motor generator MG1 is always converted into electric power by motor generator MG1) and battery charging efficiency Q is always 100% (that is, In an ideal hybrid vehicle in which all of the electric power generated by the motor generator MG1 is always stored in the battery 500), the fuel consumption rate calculation unit 102 does not take the correction coefficient α into consideration, and the engine fuel consumption rate G during power generation described above. Is multiplied by the battery input power amount d to calculate the battery input fuel consumption amount j1. However, in actual hybrid vehicle 10, MG1 power generation efficiency P is less than 100% (that is, only part of the energy input from engine ENG to motor generator MG1 is converted into electric power), and battery charging efficiency Q is 100. (That is, only a part of the electric power generated by the motor generator MG1 is stored in the battery 500). That is, in the actual hybrid vehicle 10, a part of the energy input from the engine ENG to the motor generator MG1 is often lost and a part of the electric power generated by the motor generator MG1 is often lost. In consideration of such a loss occurrence in the actual hybrid vehicle 10, the fuel consumption rate calculation unit 102 calculates the correction coefficient α.

  The MG1 power generation efficiency P is the MG1 efficiency when the motor generator MG1 functions as a generator among the MG1 efficiency described above. For example, when the total amount of energy input to the motor generator MG1 for power generation is “E1” and the total amount of power output from the motor generator MG1 as a result of power generation is “E2”, the MG1 power generation efficiency P may be an index value representing a numerical value specified by the mathematical expression E2 / E1. Hereinafter, for convenience of explanation, the description will be made assuming that the unit of the MG1 power generation efficiency P is “%”.

  The fuel consumption rate calculation unit 102 refers to a map representing the correspondence between the operating point of the motor generator MG1 (for example, the operating point specified by the torque of the motor generator MG1 and the rotation speed of the motor generator MG1) and the MG1 power generation efficiency P. Thus, it is preferable to calculate the MG1 power generation efficiency P.

  The battery charging efficiency Q is the ratio of the total amount of power energy actually stored in the battery 500 when the energy generated by the motor generator MG1 is input to the battery 500 with respect to the total amount of power energy generated by the motor generator MG1. Is an index value representing In other words, the battery charging efficiency Q is an index value that represents a ratio of the total amount of energy of power stored in the battery 500 as a result of charging to the total amount of energy input to the battery 500 for charging. For example, when the total amount of energy input to the battery 500 for charging is “E3” and the total amount of energy stored in the battery 500 as a result of charging is “E4”, the MG1 power generation efficiency P May be an index value representing a numerical value specified by the mathematical expression E2 / E1. In the following, for convenience of explanation, the description will be made assuming that the unit of the battery charging efficiency Q is “%”.

  The battery charging efficiency Q varies depending on the internal resistance of the battery 500 and the like. The internal resistance of the battery 500 is mainly determined by the specifications of the battery 500. Therefore, the fuel consumption rate calculation unit 102 is. A fixed value determined by the specifications of the battery 500 may be set as the battery charging efficiency Q. Alternatively, considering that the internal resistance or the like of the battery 500 has temperature dependency or the like, the fuel consumption rate calculation unit 102 refers to a map representing the correspondence relationship between the parameters such as the temperature and the battery charging efficiency Q. Thus, the battery charging efficiency Q may be calculated.

  As described above, the fuel consumption rate calculation unit 102 can calculate the power generation engine fuel consumption rate G and the correction coefficient α. As a result, the fuel consumption rate calculation unit 102 uses the following equation: battery input fuel consumption amount j1 = power generation engine fuel consumption rate G × correction coefficient α × battery input power amount d. A battery input fuel consumption j1 that is a fuel consumption of the engine ENG required for accumulation can be calculated. As a result, the fuel consumption rate calculation unit 102 determines that the battery fuel consumption amount J ′ = battery fuel consumption amount J + battery input fuel consumption amount j1 (= battery fuel consumption amount J + power generation engine fuel consumption rate G × correction coefficient α × battery input power amount. The battery fuel consumption J ′ can be calculated using the mathematical formula d).

  Thereafter, the fuel consumption rate calculation unit 102 divides the battery fuel consumption amount J ′ after the battery 500 is newly charged by the battery power integration amount a ′ after the battery 500 is newly charged, so that the battery Battery fuel consumption rate F ′ after 500 is newly charged is calculated (step S23). That is, the fuel consumption rate calculation unit 102 calculates the battery fuel consumption rate F ′ using a mathematical formula: battery fuel consumption rate F ′ = battery fuel consumption amount J ′ / battery power integrated amount a ′.

  Thereafter, the fuel consumption rate calculation unit 102 updates the battery fuel consumption rate F, the battery power integration amount a, and the battery fuel consumption amount J (step S26). Specifically, the fuel consumption rate calculation unit 102 sets the battery fuel consumption rate F ′ calculated in step S23 to a new battery fuel consumption rate F. The fuel consumption rate calculation unit 102 sets the battery power integration amount a ′ calculated in step S23 to a new battery power integration amount a. The fuel consumption rate calculation unit 102 sets the battery fuel consumption amount J ′ calculated in step S23 as a new battery fuel consumption amount J.

  On the other hand, as a result of the determination in step S22, when it is determined that the battery 500 is not newly charged (that is, no new electric power is input to the battery 500) (step S22: No), the fuel consumption rate The calculation unit 102 determines whether or not the battery 500 is newly discharged (that is, whether or not power is newly output from the battery 500) (step S24).

  As a result of the determination in step S24, when it is determined that the battery 500 is newly discharged (that is, new power is output from the battery 500) (step S24: Yes), the fuel consumption rate calculation unit 102 Battery fuel consumption rate F ′ after 500 is newly discharged is calculated (step S25).

  Specifically, the fuel consumption rate calculation unit 102 calculates the battery power integration amount a ′ after the battery 500 is newly discharged (step S25). When the battery 500 is newly discharged, the battery power integrated amount a ′ is greater than the battery power integrated amount a before the battery 500 is newly discharged, and the total amount c of power that the battery 500 has newly discharged (hereinafter, It should be reduced by “battery output power amount c”). Therefore, the fuel consumption rate calculation unit 102 calculates the battery power integration amount a ′ by subtracting the battery output power amount c from the battery power integration amount a. That is, the fuel consumption rate calculation unit 102 calculates the battery power integration amount a ′ using the mathematical formula: battery power integration amount a ′ = battery power integration amount a−battery output power amount c.

  In addition, the fuel consumption rate calculation unit 102 calculates the battery fuel consumption J ′ after the battery 500 is newly discharged (step S25). When the battery 500 is newly discharged, since the battery power integration amount a ′ is smaller than the battery power integration amount a, the battery fuel consumption amount J ′ is the battery before the battery 500 is newly discharged. The fuel consumption J should be reduced by the fuel consumption J of the engine ENG (hereinafter referred to as “battery output fuel consumption j2”) required for accumulating the battery output power c. . Therefore, the fuel consumption rate calculation unit 102 calculates the battery output fuel consumption amount j2 and calculates the battery fuel consumption amount J ′ by subtracting the calculated battery output fuel consumption amount j2 from the battery fuel consumption amount J. . That is, the fuel consumption rate calculation unit 102 calculates the battery fuel consumption amount J ′ by using the mathematical formula: battery fuel consumption amount J ′ = battery fuel consumption amount J−battery output fuel consumption amount j2.

  The fuel consumption rate calculation unit 102 may calculate the battery output fuel consumption amount j using a mathematical formula: battery output fuel consumption amount j2 = battery fuel consumption rate F × battery output power amount c. This is because the power of the battery output power amount c newly discharged from the battery 500 is a part of the power of the battery power integrated amount a stored in the battery 500. Accordingly, the battery fuel consumption rate F when the battery power integration amount c is stored should be the same as the battery fuel consumption rate F when the battery power integration amount a is stored. Accordingly, the battery output fuel consumption j2 that is the fuel consumption of the engine ENG required to store the power of the battery output power amount c that is a part of the battery power integration amount a is battery fuel consumption rate F × battery output power. It is calculated from a mathematical formula called quantity c.

  Thereafter, the fuel consumption rate calculation unit 102 divides the battery fuel consumption J ′ after the battery 500 is newly discharged by the battery power integrated amount a ′ after the battery 500 is newly discharged, so that the battery 500 The battery fuel consumption rate F ′ after newly discharging is calculated (step S25). That is, the fuel consumption rate calculation unit 102 calculates the battery fuel consumption rate F ′ using a mathematical formula: battery fuel consumption rate F ′ = battery fuel consumption amount J ′ / battery power integrated amount a ′. Thereafter, the fuel consumption rate calculation unit 102 updates the battery fuel consumption rate F, the battery power integration amount a, and the battery fuel consumption amount J (step S26).

  On the other hand, as a result of the determination in step S24, when it is determined that the battery 500 is not newly discharged (that is, no new power is output from the battery 500) (step S24: Yes), the battery 500 is determined. It is estimated that the total amount of electric power stored in has not changed. That is, it is estimated that the battery fuel consumption rate F, the battery power integration amount a, and the battery fuel consumption amount J are not substantially changed. Therefore, in this case, the fuel consumption rate calculation unit 102 does not have to calculate the battery fuel consumption rate F ′. In other words, the fuel consumption rate calculation unit 102 does not have to update the battery fuel consumption rate F, the battery power integration amount a, and the battery fuel consumption amount J.

  Thereafter, the fuel consumption rate comparison unit 103 determines whether or not the battery fuel consumption rate F updated in step S26 is greater than the running engine fuel consumption rate H calculated by the fuel consumption rate calculation unit 102 (step S31). The running engine fuel consumption rate H is a specific example of “engine cost”.

  The engine fuel consumption rate H at the time of travel is the engine ENG per unit travel output that is estimated to be required for the hybrid vehicle 10 to travel using the power of the engine ENG while not using the power of the motor generators MG1 and MG2. This is an index value representing the fuel consumption. In other words, the engine fuel consumption rate HG during travel is determined by the hybrid vehicle 10 not using the power of the motor generators MG1 and MG2 while using the power of the engine ENG. This represents the fuel consumption amount of the engine ENG that is estimated to be required to output a unit travel output corresponding to (quantity). For example, in order to output the travel output “X6” when the hybrid vehicle 10 travels using the power of the engine ENG while the power of the motor generators MG1 and MG2 is not used. When it is estimated that the amount of fuel “Y6” will be consumed by the engine ENG, the running engine fuel efficiency H is an index value representing a numerical value specified by the mathematical formula “Y6 / X6”. May be. Hereinafter, for convenience of explanation, the description will be made assuming that the unit of the engine fuel efficiency during running H is “g / kWh”. However, the unit of the engine fuel efficiency H during travel is preferably the same as the unit of the battery fuel efficiency F.

  Similarly to the power generation engine fuel consumption rate G, the fuel consumption rate calculation unit 102 can calculate the running engine fuel consumption rate H by referring to a map representing the correspondence relationship between the operating point of the engine ENG and the engine fuel consumption rate. preferable. For example, the fuel consumption rate calculation unit 102 refers to the position on the map of the operating point of the engine ENG when the hybrid vehicle 10 travels using the power of the engine ENG while not using the power of the motor generators MG1 and MG2. Thus, the engine fuel consumption rate H during traveling is calculated.

  As a result of the determination in step S31, when it is determined that the battery fuel consumption rate F is greater than the running engine fuel consumption rate H (step S31: Yes), the travel mode control unit 101 determines that the travel mode of the hybrid vehicle 10 is HV. The hybrid vehicle 10 is controlled so as to be in the mode (step S11).

  On the other hand, as a result of the determination in step S <b> 31, when it is determined that the running engine fuel efficiency H is higher than the battery fuel efficiency F (step S <b> 31: No), the travel mode control unit 101 travels the hybrid vehicle 10. The hybrid vehicle 10 is controlled so that the mode becomes the EV mode (step S13).

  However, even if it is determined that the running engine fuel efficiency H is greater than the battery fuel efficiency F, if the SOC of the battery 500 is excessively reduced (for example, smaller than a predetermined threshold) ( In step S12: Yes), the traveling mode control unit 101 controls the hybrid vehicle 10 so that the traveling mode of the hybrid vehicle 10 becomes the HV mode (step S13). As a result, the SOC of battery 500 is recovered (that is, increased) by motor generator MG1 functioning as a generator using the power of engine ENG.

  As described above, in the hybrid vehicle 10 of the present embodiment, the travel mode of the hybrid vehicle 10 is determined based on the determination result of whether or not the battery fuel consumption rate F is greater than the running engine fuel consumption rate H. As a result, the hybrid vehicle 10 can travel while selecting a travel mode that can suitably improve fuel efficiency. The reason will be described below.

  First, the battery fuel consumption rate F represents the fuel consumption amount of the engine ENG per unit electric energy required for accumulating the electric power accumulated in the battery 500. Therefore, it can be said that the battery fuel consumption rate G substantially represents the fuel consumption of the hybrid vehicle 10 that travels in the EV mode using the electric power stored in the battery 500. In other words, it can be said that the battery fuel consumption rate G substantially represents the fuel consumption of the hybrid vehicle 10 that outputs the unit travel output in the EV mode. On the other hand, the engine fuel consumption rate H during travel exactly represents the fuel consumption of the hybrid vehicle 10 that travels in the HV mode using the power of the engine ENG. In other words, it can be said that the engine fuel efficiency during running H represents the fuel consumption of the hybrid vehicle 10 that outputs the unit running output in the HV mode.

  Therefore, when the battery fuel consumption rate F is larger than the running engine fuel consumption rate H, the fuel consumption amount (specifically, the fuel consumption amount per unit travel output) of the hybrid vehicle 10 traveling in the EV mode is HV. It is assumed that the fuel consumption of the hybrid vehicle 10 traveling in the mode (specifically, the fuel consumption per unit travel output) is larger. Here, the increase in the fuel consumption amount per unit travel output leads to the deterioration of the fuel consumption of the hybrid vehicle 10 (particularly, the fuel consumption when viewed from the entire travel of the hybrid vehicle 10). Therefore, when the battery fuel consumption rate F is larger than the running engine fuel consumption rate H, it is assumed that the fuel consumption of the hybrid vehicle 10 traveling in the EV mode is worse than the fuel consumption of the hybrid vehicle 10 traveling in the HV mode. Is done.

  On the other hand, when the running engine fuel efficiency H is larger than the battery fuel efficiency F, the fuel consumption (specifically, the fuel consumption per unit travel output) of the hybrid vehicle 10 traveling in the HV mode is: It is assumed that the fuel consumption of the hybrid vehicle 10 traveling in the EV mode (specifically, the fuel consumption per unit travel output) is larger. Therefore, when the running engine fuel consumption rate H is larger than the battery fuel consumption rate F, it is assumed that the fuel consumption of the hybrid vehicle 10 traveling in the HV mode is worse than the fuel consumption of the hybrid vehicle 10 traveling in the EV mode. Is done.

  Therefore, in the present embodiment, when the battery fuel consumption rate F is greater than the running engine fuel consumption rate H, the hybrid vehicle 10 travels in the HV mode in which the fuel consumption per unit travel output is relatively small. On the other hand, when the running engine fuel efficiency H is higher than the battery fuel efficiency F, the hybrid vehicle 10 travels in the EV mode in which the fuel consumption per unit travel output is relatively small. As a result, in the present embodiment, the hybrid vehicle 10 can travel while appropriately determining a travel mode in which the fuel consumption per unit travel output is relatively small. Here, the reduction in fuel consumption per unit travel output leads to an improvement in the fuel consumption of the hybrid vehicle 10 (particularly, the fuel consumption when viewed as a whole travel of the hybrid vehicle 10). Therefore, the hybrid vehicle 10 can travel while appropriately determining a travel mode that can suitably improve fuel consumption.

  In particular, in the present embodiment, the battery fuel consumption rate F represents the fuel consumption amount of the engine ENG per unit amount of electric power. Therefore, the battery fuel consumption rate F includes the engine driven to accumulate electric power in the battery 500. The ENG drive efficiency (that is, the engine efficiency described above) is reflected.

  For example, when a predetermined amount of electric power is accumulated in the battery 500 by driving the engine ENG in a state where the engine efficiency is relatively poor, the total amount of fuel consumption becomes relatively large. F becomes relatively large. On the other hand, when the same predetermined amount of power is accumulated in the battery 500 by driving the engine ENG with relatively good engine efficiency, the total amount of fuel consumption is relatively small. The battery fuel consumption rate F becomes relatively small. As described above, even when the same amount of power is stored in the battery 500, the fuel consumption required to store the power is not necessarily the same. That is, even when the same amount of power is stored in the battery 500, the value of the power stored in the battery 500 is not necessarily the same. Thus, even if the battery fuel consumption rate F is the case where the same amount of electric power is stored in the battery 500, the fuel consumption required to store the electric power (in other words, when the electric power is stored) It can be said that the value of electric power is appropriately represented because it varies depending on the engine efficiency of the engine ENG.

  Similarly, for example, when the engine ENG consumes a predetermined amount of fuel while the engine efficiency is relatively poor in order to store power in the battery 500, the total amount of power stored in the battery 500 is relatively Therefore, the battery fuel consumption rate F is relatively increased. On the other hand, when the engine ENG consumes the same predetermined amount of fuel while the engine efficiency is relatively good in order to store power in the battery 500, the total amount of power stored in the battery 500 is relatively Therefore, the battery fuel consumption rate F becomes relatively large. As described above, even when electric power is stored in the battery 500 because the engine ENG consumes the same amount of fuel, the total amount of stored electric power is not always the same. That is, even if electric power is stored in the battery 500 because the engine ENG consumes the same amount of fuel, the value of the electric power stored in the battery 500 is not necessarily the same. Thus, the battery fuel consumption rate F is the total amount of electric power stored in the battery 500 (in other words, electric power even if electric power is stored in the battery 500 due to the engine ENG consuming the same amount of fuel). Therefore, it can be said that the value of electric power is appropriately represented.

  For this reason, in the present embodiment, the hybrid vehicle 10 has a traveling mode in which the fuel efficiency is relatively good (or optimal) in consideration of the value of the electric power stored in the battery 500. It is possible to travel while appropriately determining. Therefore, the hybrid vehicle 10 can travel while appropriately determining a travel mode that can suitably improve fuel consumption.

  In addition, in the present embodiment, the battery fuel consumption rate F represents the fuel consumption amount of the engine ENG per unit electric energy required to accumulate all the electric power accumulated in the battery 500. That is, the battery fuel consumption rate F is a unit of the amount of electric power required to store only the electric power newly stored in the battery 500 (in other words, only a part of the total electric power stored in the battery 500). It does not represent the fuel consumption of the engine ENG. Therefore, the hybrid vehicle 10 accumulates not only the fuel consumption of the engine ENG per unit electric energy required for accumulating the electric power newly accumulated in the battery 500 but also the electric power already accumulated in the battery 500. In consideration of the fuel consumption amount of the engine ENG per unit electric energy required for this, it is possible to travel while appropriately determining a travel mode in which the fuel efficiency is relatively good (or optimal).

  Here, as a comparative example, for example, the battery fuel consumption rate of the comparative example representing the fuel consumption amount of the engine ENG per unit electric energy required for storing only the electric power newly stored in the battery 500 is the engine fuel consumption during driving. A hybrid vehicle of a comparative example that travels in the EV mode when the rate H is smaller is assumed. The hybrid vehicle of the comparative example travels with the battery fuel efficiency of the comparative example without depending on the amount of fuel consumption of the engine ENG per unit power amount required to store the electric power already stored in the battery 500. When the hour engine fuel consumption rate H is smaller, the vehicle travels in the EV mode. However, even if the battery fuel consumption rate of the comparative example is smaller than the engine fuel consumption rate H during driving, the fuel consumption of the engine ENG per unit electric energy required to store the power already stored in the battery 500 The amount may be relatively large. That is, the fuel consumption rate of the engine ENG per unit electric energy required to store all the electric power stored in the battery 500 while the battery fuel consumption rate of the comparative example is smaller than the engine fuel consumption rate H during traveling. There is a possibility that the battery fuel consumption rate F becomes larger than the running engine fuel consumption rate H. In such a case, the hybrid vehicle of the comparative example does not always have a relatively small fuel consumption per unit travel output (that is, the fuel efficiency is not always improved). ) However, the hybrid vehicle 10 of the present embodiment is stored in the battery 500 instead of the fuel consumption of the engine ENG per unit electric energy required to store only the electric power newly stored in the battery 500. The travel mode is determined based on the battery fuel consumption rate F representing the fuel consumption amount of the engine ENG per unit power amount required to store all the electric power. Therefore, compared to the hybrid vehicle of the comparative example, the hybrid vehicle 10 of the present embodiment has a relatively small fuel consumption per unit travel output (that is, the fuel efficiency becomes relatively good or optimum). ) It is possible to travel while appropriately determining the travel mode. Therefore, compared with the hybrid vehicle of the comparative example, the hybrid vehicle 10 of the present embodiment can travel while appropriately determining a travel mode that can suitably improve fuel efficiency.

  Furthermore, in the present embodiment, the operating point control unit 104 controls the operating points of the engine ENG and the motor generator MG1 before the travel mode control unit 103 determines the travel mode. That is, before the travel mode control unit 103 determines the travel mode, the MG1 efficiency (MG1 power generation efficiency P) becomes a relatively good value. Here, when the MG1 efficiency becomes a relatively good value, the initial value of the battery fuel efficiency F becomes relatively small. This is because the fuel consumption of the engine ENG required for accumulating the same amount of power in the battery 500 decreases as the MG1 efficiency becomes a relatively good value. Further, considering that the MG1 efficiency (MG1 power generation efficiency P) is used for calculating the battery fuel consumption J ′ (in other words, updating the battery fuel consumption J) as part of the correction coefficient α, MG1 When the efficiency is a relatively good value (that is, the correction coefficient α is relatively small), the battery fuel consumption J is relatively small. As a result, when the MG1 efficiency is a relatively good value, the battery fuel consumption rate F is relatively small as compared to the case where the MG1 efficiency is not a relatively good value. That is, when the MG1 efficiency becomes a relatively good value, it is determined that the battery fuel efficiency rate F is larger than the traveling engine fuel efficiency rate H compared to the case where the MG1 efficiency does not become a relatively good value. It becomes difficult to be done. As a result, the frequency with which the hybrid vehicle 10 travels in the EV mode becomes relatively high. Accordingly, the fuel efficiency of the hybrid vehicle 10 is relatively improved.

  However, the operating point control unit 104 may control the operating points of the engine ENG and the motor generator MG1 after the travel mode control unit 103 determines the travel mode. Even in this case, as a result of the control of the operating points of the engine ENG and the motor generator MG1 by the operating point control unit 104, the motor generator MG1 can generate electric power with a relatively good MG1 efficiency. There is no change.

  In consideration of the fact that the fuel efficiency of the hybrid vehicle 10 is relatively improved by controlling the outputs of the engine ENG and the motor generator MG1 before the travel mode is determined, the travel characteristics with an emphasis on fuel efficiency performance are obtained. The timing at which the travel mode control unit 103 determines the travel mode and the timing at which the operating point control unit 104 controls the outputs of the engine ENG and the motor generator MG1 depending on whether or not the hybrid vehicle 10 is required. It may be adjusted. For example, when the hybrid vehicle 10 is required to have a driving characteristic that places greater emphasis on fuel consumption performance than driving performance (driving response), the operating point control unit 104 before the driving mode control unit 103 determines a driving mode. The operating points of engine ENG and motor generator MG1 may be controlled in the manner shown in FIG. On the other hand, for example, when the hybrid vehicle 10 is required to have a driving characteristic that emphasizes the driving performance rather than the fuel efficiency, the operating point control unit 104 determines the driving mode after the driving mode control unit 103 determines the driving mode. The operating points of engine ENG and motor generator MG1 may be controlled in the manner shown in FIG.

  It should be noted that the present invention can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification, and a vehicle control device that includes such a change is also included in the technical concept of the present invention. included.

10 Hybrid vehicle 100 ECU
DESCRIPTION OF SYMBOLS 101 Travel mode control part 102 Fuel consumption rate calculation part 103 Fuel consumption rate comparison part 104 Operating point control part 500 Battery ENG Engine MG1, MG2 Motor generator F, F 'Battery fuel consumption rate H Engine fuel consumption rate

Claims (1)

A vehicle control device for controlling a hybrid vehicle comprising an internal combustion engine and a rotating electrical machine capable of charging a rechargeable battery capable of storing electric power by being driven using the power of the internal combustion engine,
(I) The charging cost representing the fuel consumption of the internal combustion engine required to store the unit electric energy of the electric power stored in the rechargeable battery is the power of the internal combustion engine without using the power of the rotating electrical machine. When the hybrid vehicle is smaller than the engine cost representing the fuel consumption of the internal combustion engine required for the hybrid vehicle to output a unit travel output corresponding to the unit power amount, the travel mode of the hybrid vehicle is the internal combustion engine. (Ii) when the charging cost is greater than the engine cost, the driving mode is an engine mode that uses the power of the internal combustion engine to drive the engine. First control means for performing mode control for controlling the hybrid vehicle;
The efficiency control is performed to control the rotating electrical machine and the internal combustion engine so that the required output required for the hybrid vehicle is satisfied and the driving efficiency of the entire drive source including the rotating electrical machine and the internal combustion engine is maximized. 2 control means,
When the characteristic required for the hybrid vehicle is a characteristic in which fuel efficiency is more important than driving performance, the mode control is performed by the first control unit after the efficiency control is performed by the second control unit. A vehicle control device characterized by that.

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