JP2012086645A - Control device and controlling method of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the control device of a hybrid vehicle which can guarantee following property of an internal combustion engine to a required output, even when an increase in power generation output is requested since a capacitor cannot output requested output power.SOLUTION: The control device of the vehicle includes: a power generating part including a combustion engine and a power generator generating power by driving of the combustion engine; a power storage part for supplying power to a motor which is the driving source of the vehicle; and a driving part driving the vehicle by power supply from at least one of the power storage part or the power generator part. When the control device determines that, after output power requested to the driving part is derived, according to AP opening and the state of the motor, the power generating part can not output power corresponding to output power requested to the driving part, and the power storage part can not output power storage part required output which is a difference between the output power requested to the driving part and the output power of the power generator, a parameter related to burning control of the combustion engine is derived, corresponding to a correction power generator output which is a difference between the output requested to the driving part and the possible output of the power storage part, and a storage power part output limit amount which is a difference between power storage part required output and the possible output amount of a capacitor.

Description

  The present invention relates to a control device and a control method for a hybrid vehicle.

  The battery control device disclosed in Patent Literature 1 controls charging / discharging restrictions according to the magnitude of charging / discharging power. The battery control device includes: a first determination unit configured to determine whether a cell voltage is equal to or lower than a first overdischarge comparison voltage in a battery in which a plurality of battery cells are connected in series; A second determination unit configured to determine whether the voltage is lower than a second low overdischarge comparison voltage; and a second discharge limitation unit configured to limit the discharge power of the battery when the cell voltage is equal to or lower than the second overdischarge comparison voltage. . The second discharge limiting means controls the limit of the discharge power according to the time until the cell voltage reaches the second overdischarge comparison voltage from the first overdischarge comparison voltage. Thereby, the restriction | limiting according to the magnitude | size of discharge electric power can be performed. In other words, when the discharge power is large and the cell voltage suddenly decreases, or when the discharge power is small and the cell voltage changes slowly, overdischarge or excessive discharge restriction may occur. Can be suppressed.

  Patent Document 1 describes that the battery control device described above is mounted on, for example, a series hybrid vehicle. FIG. 13 is a block diagram showing a schematic configuration of the series hybrid vehicle disclosed in Patent Document 1. As shown in FIG. As shown in FIG. 13, the power train of the series hybrid vehicle includes an engine 1, a power generation motor 2 that converts power of the engine 1 directly connected to the engine 1 into power, and power generated by the power generation motor 2 or a hybrid vehicle. The battery 6 which stores the electric power which arises by driving | running | working is provided. In addition, a drive motor 3 that is driven by using the electric power stored in the battery 6 is provided, and the torque of the drive motor 3 is transmitted to the tire 5 via the final gear 4. The engine 1 is operated at a rotation speed that can be output at the best fuel ratio.

JP 2004-166368 A

  A series hybrid vehicle equipped with the above-described battery control device may be liable to decrease drivability in some situations due to discharge power limit control. FIG. 14 is a graph showing the passage of time of (a) the output of the drive motor 3, (b) the output of the engine 1, and (c) the output of the battery 6 when the discharge power is limited. In FIG. 14A, the required output of the drive motor 3 corresponding to the required drive force is represented by a dotted line. Although the output of the battery 6 increases in accordance with the required driving force, the output reaches a discharge power limit value indicated by a one-dot chain line in FIG. 14C due to the discharge power limit control. On the other hand, the engine 1 drives the generator motor 2 to supplement the output of the battery 6. However, the output of the engine 1 increases according to the characteristics regardless of whether or not the discharge power limit control is performed. As a result, as indicated by a solid line in FIG. 14A, the actual output of the drive motor 3 while the output of the battery 6 is suppressed to the discharge power limit value does not satisfy the required output indicated by the dotted line. .

  14 (a) to 14 (c) show an example in which the output of the battery 6 is suppressed by the discharge power limiting control by the battery control device, but the remaining capacity (SOC: State of Charge) and deterioration of the battery 6 are shown. The output of the battery 6 can also be limited by the state, temperature, and the like. For example, regarding the temperature, in general, the output of the secondary battery decreases when the temperature is high or low. Therefore, the discharge power that can be output from the battery 6 at the time of high temperature or low temperature is lower than normal, and the actual output of the drive motor 3 may not satisfy the required output as in the above example.

  Even if the above-described discharge power limit control is performed, even if the battery 6 is at a high temperature or a low temperature, if the capacity of the battery 6 is sufficient, sufficient drivability can be achieved even in the worst environment assumed. Is obtained. However, since a battery having a large capacity is expensive and heavy, a method of simply increasing the capacity of the battery is not preferable.

  Further, as shown in FIG. 14C, when the actual output of the battery 6 does not satisfy the required output, the output of the generator motor 2 driven by the engine 1 can be supplemented with the output that does not satisfy the required output. If possible, drivability can be prevented from decreasing. However, when the engine 1 is operated at a fixed point at a constant rotational speed with the best fuel efficiency, followability to the required output is not good. For this reason, the drivability degradation which is a problem in the above example cannot be solved.

  An object of the present invention is to provide a control device and a control method for a hybrid vehicle capable of ensuring the follow-up performance of an internal combustion engine with respect to a required output even when an increase in power generation output is required because the capacitor cannot output the required output. Is to provide.

  In order to solve the above-described problems and achieve the object, a hybrid vehicle control device according to a first aspect of the present invention includes an internal combustion engine (for example, the internal combustion engine 109 in the embodiment) and an operation of the internal combustion engine. A power generation unit (for example, the power generation unit 123 in the embodiment) having a power generator (for example, the power generator 111 in the embodiment) and a capacitor (for example, a power supply that supplies electric power to an electric motor that is a drive source of the hybrid vehicle) The power storage unit (for example, the power storage unit 121 in the embodiment) having the power storage unit 101 in the embodiment, and the electric motor (for example, implementation) driven by power supply from at least one of the power storage unit and the generator And a drive unit (for example, the drive unit 125 in the embodiment) having the electric motor 107 in the form of the hybrid vehicle control device (for example, the embodiment) Management ECU 119), and a drive unit required output deriving unit (for example, for deriving an output required for the drive unit in accordance with an accelerator pedal opening corresponding to an accelerator operation and a state of the electric motor in the hybrid vehicle) Based on the characteristics of the required drive force calculation unit 201 and the drive unit required output calculation unit 203) and the power generation unit in the embodiment, the power generation unit can output an output corresponding to the output requested of the drive unit A power generation unit output capability determination unit (for example, a power generation unit output capability determination unit 205 in the embodiment) that determines whether or not the power generation unit cannot output an output corresponding to the output requested of the drive unit When determined, the power storage unit outputs the power storage unit required output, which is the difference between the output requested of the drive unit and the output of the power generation unit, based on the information about the battery. Power storage unit output enable determination unit (for example, power storage unit required output calculation unit 207 and power storage unit output enable determination unit 209 in the embodiment) for determining whether or not the power storage unit outputs the power storage unit required output When it is determined that it cannot be performed, the corrected power generation unit output that is the difference between the output requested by the drive unit and the output that can be performed by the power storage unit, and the power storage that is the difference between the output required by the power storage unit and the output that can be performed by the battery A combustion control value deriving unit (for example, a corrected power generation unit output calculating unit 211 and a combustion control value deriving unit 213 in the embodiment) for deriving a parameter related to combustion control of the internal combustion engine according to a partial output limit amount; An internal combustion engine operating point deriving unit (for example, an internal combustion engine operating point deriving unit 215 in the embodiment) for deriving a target operating point of the internal combustion engine according to the corrected power generation unit output and the power storage unit output limit amount; With this It is characterized by.

  Furthermore, in the hybrid vehicle control device according to claim 2, the combustion control value deriving unit sets the power storage unit output limit to a basic parameter related to combustion control of the internal combustion engine according to the corrected power generation unit output. A parameter relating to combustion control of the internal combustion engine is derived by multiplying a correction coefficient corresponding to the amount.

  Further, in the control apparatus for a hybrid vehicle according to a third aspect of the present invention, the combustion control of the internal combustion engine is EGR control, Atkinson control, air-fuel ratio adjustment control, or a combination of these controls.

  Furthermore, in the hybrid vehicle control apparatus according to claim 4, when the combustion control of the internal combustion engine is EGR control, the parameter relating to the combustion control of the internal combustion engine indicates an introduction amount of EGR, and the correction is performed. The coefficient is smaller as the power storage unit output limit amount is larger.

  Furthermore, in the hybrid vehicle control apparatus according to the fifth aspect of the present invention, when the combustion control of the internal combustion engine is Atkinson control, the parameter relating to the combustion control of the internal combustion engine is the slow closing of the intake valve in the internal combustion engine. The correction coefficient is smaller as the power storage unit output limit amount is larger.

  Furthermore, in the hybrid vehicle control device according to the sixth aspect of the present invention, when the combustion control of the internal combustion engine is air-fuel ratio adjustment control, the parameter relating to the combustion control of the internal combustion engine includes the power storage unit output limit amount. If it is less than a predetermined value, it indicates permission of the lean operation of the internal combustion engine, and if the power storage unit output limit amount is not less than the predetermined value, it indicates prohibition of the lean operation of the internal combustion engine.

  Further, in the hybrid vehicle control device of the invention according to claim 7, the internal combustion engine operating point deriving unit derives a target operating point having a higher rotational speed as the power storage unit output limit amount increases. .

  Furthermore, in the hybrid vehicle control method according to the eighth aspect of the present invention, an internal combustion engine, a power generation unit having a power generator that generates power by the operation of the internal combustion engine, and a capacitor that supplies power to an electric motor that is a drive source of the hybrid vehicle. And a drive unit having the electric motor driven by power supply from at least one of the power storage unit and the generator, the accelerator operation in the hybrid vehicle The output required for the drive unit is derived according to the accelerator pedal opening according to the condition and the state of the electric motor, and the output corresponding to the output required for the drive unit is obtained based on the characteristics of the power generation unit. It is determined whether or not the power generation unit can output, and it is determined that the power generation unit cannot output an output corresponding to the output requested of the drive unit. And determining whether or not the power storage unit can output a power storage unit required output, which is a difference between the output requested of the drive unit and the output of the power generation unit, based on the information related to the power storage unit. Determines that the power storage unit required output cannot be output, the corrected power generation unit output that is the difference between the output requested by the drive unit and the power storage unit possible output, and the power storage unit required output and the battery A parameter relating to combustion control of the internal combustion engine in accordance with the power storage unit output limit amount, which is a difference in power output, and a target operation of the internal combustion engine in accordance with the corrected power generation unit output and the power storage unit output limit amount It is characterized by deriving points.

  According to the hybrid vehicle control device of the first to seventh aspects of the invention and the hybrid vehicle control method of the eighth aspect of the invention, when the power generation device is unable to produce the required output, an increase in the power generation output is required. Even so, the followability of the internal combustion engine to the required output can be ensured.

Block diagram showing the internal configuration of a series-type HEV Conceptual diagram of the internal configuration of the internal combustion engine 109 in which EGR control or the like is performed The block diagram which shows the internal structure of management ECU119 The figure which shows the input-output relationship and efficiency of the electrical storage part 121, the electric power generation part 123, and the drive part 125. The flowchart which shows the control method of the internal combustion engine 109 by management ECU119 of 1st Example. The flowchart which shows the control method of the internal combustion engine 109 by management ECU119 of 1st Example. Diagram showing output-target NE graph The figure which shows the graph which shows the characteristic regarding the thermal efficiency of the internal combustion engine 109 Conceptual diagram showing the process of deriving the target EGR value by the combustion control value deriving unit 213 The figure which shows correction | amendment electric power generation part output-target NE graph The figure which shows the graph which shows the characteristic regarding the thermal efficiency of the internal combustion engine 109 Conceptual diagram showing the process of deriving the target INV value by the combustion control value deriving unit 213 Block diagram showing a schematic configuration of a series hybrid vehicle disclosed in Patent Document 1 A graph showing the elapsed time of (a) the output of the drive motor 3, (b) the output of the engine 1, and (c) the output of the battery 6 when the discharge power is limited.

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

  A HEV (Hybrid Electrical Vehicle) includes an electric motor and an internal combustion engine, and travels by the driving force of the electric motor and / or the internal combustion engine according to the traveling state of the vehicle. There are two types of HEVs: a series method and a parallel method. The series-type HEV travels by the power of the electric motor. The internal combustion engine is used only for power generation, and the electric power generated by the power generator by the power of the internal combustion engine is charged in the capacitor or supplied to the electric motor. On the other hand, the parallel HEV travels by the power of either or both of the electric motor and the internal combustion engine.

  A series / parallel HEV in which both the above systems are combined is also known. In this method, the transmission system for driving force is switched to either the series method or the parallel method by disconnecting or engaging (disengaging) the clutch according to the traveling state of the vehicle. In particular, the clutch is disengaged during low-speed traveling to form a series structure, and particularly during medium-high speed traveling, the clutch is engaged to form a parallel structure.

  In the embodiments described below, a hybrid vehicle control device according to the present invention is mounted on a series-type HEV. The series-type HEV includes an electric motor, an internal combustion engine, and a generator, and travels by using the power of an electric motor that is mainly driven by a capacitor as a power source. The internal combustion engine is used only for power generation, and the electric power generated by the generator by the power of the internal combustion engine is supplied to the electric motor or charged in the capacitor.

  The series-type HEV performs “EV traveling” or “series traveling”. In “EV traveling”, HEV travels by the driving force of an electric motor that is driven by power supply from a capacitor. At this time, the internal combustion engine is not driven. Further, in “series travel”, the HEV travels by the driving force of an electric motor that is driven by the supply of power from both the power storage device and the generator or the supply of power from only the generator. At this time, the internal combustion engine is driven for power generation in the generator. When the HEV performs series travel, the battery also supplies power to the electric motor when the required driving force cannot be satisfied with the power generation output of the generator driven by the internal combustion engine. That is, the output of the capacitor compensates for the shortage of the generator output relative to the required driving force.

  FIG. 1 is a block diagram showing the internal configuration of a series-type HEV. As shown in FIG. 1, a series-type HEV includes a battery (BATT) 101, a converter (CONV) 103, a first inverter (first INV) 105, an electric motor (Mot) 107, and an internal combustion engine (ENG) 109. And a generator (GEN) 111, a second inverter (second INV) 113, a gear box (hereinafter simply referred to as “gear”) 115, and a management ECU (MG ECU) 119.

  The storage battery 101 has a plurality of storage cells connected in series, and supplies a high voltage of, for example, 100 to 200V. The storage cell is, for example, a lithium ion battery or a nickel metal hydride battery. Converter 103 boosts or steps down the DC output voltage of battery 101 while maintaining DC. The first inverter 105 converts a DC voltage into an AC voltage and supplies a three-phase current to the electric motor 107. Further, the first inverter 105 converts the AC voltage input during the regenerative operation of the electric motor 107 into a DC voltage and charges the battery 101.

  The electric motor 107 generates power for running the HEV. Torque generated by the electric motor 107 is transmitted to the drive shaft 151 via the gear 115. Note that the rotor of the electric motor 107 is directly connected to the gear 115. In addition, the electric motor 107 operates as a generator during regenerative braking, and the electric power generated by the electric motor 107 is charged in the capacitor 101. The internal combustion engine 109 is used to drive the generator 111 when the HEV travels in series. The internal combustion engine 109 is directly connected to the rotor of the generator 111. The internal combustion engine 109 uses techniques such as EGR (Exhaust Gas Recirculation) control, Atkinson control that delays the closing timing of the intake valve according to the load, or air-fuel ratio adjustment control. Note that the management ECU 119 performs these controls for the internal combustion engine 109.

  FIG. 2 is a conceptual diagram of an internal configuration of the internal combustion engine 109 in which EGR control or the like is performed. As shown in FIG. 2, the internal combustion engine 109 is provided with an EGR passage 161b that connects the exhaust system and the intake system of the internal combustion engine 109, and an EGR valve 161a that adjusts the EGR amount. In the internal combustion engine 109, the amount of exhaust gas to be recirculated is controlled by adjusting the opening degree of the EGR valve 161a provided in the EGR passage 161b. Further, in the internal combustion engine 109 in which Atkinson control is performed, control for delaying the closing timing of the intake valve 163 from normal is performed according to the load. By making the intake valve 163 closing timing later than usual, the amount of intake air is reduced, and it is not necessary to throttle the intake pipe 167 with the throttle valve 165. Therefore, the pumping loss can be reduced and the fuel consumption can be improved. Further, in the internal combustion engine 109 in which the air-fuel ratio adjustment control is performed, the lean operation that makes the air-fuel mixture thinner than the stoichiometric air-fuel ratio by adjusting the amount of fuel injected by the fuel injection valve 169, and the stoichiometric equivalent to the stoichiometric air-fuel ratio. Either the operation or the rich operation in which the air-fuel mixture is made thinner than the stoichiometric air-fuel ratio is performed.

  The generator 111 is driven by the power of the internal combustion engine 109 to generate electric power. The electric power generated by the generator 111 is charged in the battery 101 or supplied to the electric motor 107. The second inverter 113 converts the AC voltage generated by the generator 111 into a DC voltage. The electric power converted by the second inverter 113 is charged in the battery 101 or supplied to the electric motor 107 via the first inverter 105.

  The gear 115 is a one-stage fixed gear corresponding to, for example, the fifth speed. Therefore, the gear 115 converts the driving force from the electric motor 107 into a rotation speed and torque at a specific gear ratio, and transmits them to the drive shaft 151.

  The management ECU 119 performs control of the internal combustion engine 109 and the electric motor 107 and the like. In addition, the management ECU 119 performs switching control of the switching elements that constitute the first inverter 105 and the second inverter 113, respectively. Further, as shown by a dotted line in FIG. 1, the management ECU 119 includes information indicating the temperature of the battery 101, information indicating the rotation speed and torque of the electric motor 107, information indicating the rotation speed and torque of the generator 111, and Information indicating the accelerator pedal opening (AP opening) corresponding to the accelerator operation of the HEV driver is acquired. These pieces of information are sent to the management ECU 119 from a sensor (not shown) that detects each parameter.

  FIG. 3 is a block diagram showing an internal configuration of the management ECU 119. As shown in FIG. 3, the management ECU 119 includes a required driving force calculation unit 201, a drive unit required output calculation unit 203, a power generation unit output capability determination unit 205, a power storage unit required output calculation unit 207, and a power storage unit output possible. The determination unit 209, the corrected power generation unit output calculation unit 211, the combustion control value deriving unit 213, and the internal combustion engine operating point deriving unit 215 are included. In addition, the solid line arrow in FIG. 3 indicates value data, and the dotted line indicates control data including instruction contents.

  Hereinafter, the operation of each component of the management ECU 119 in the HEV during series travel and a method for controlling the internal combustion engine 109 by the management ECU 119 will be described. In the following description, as shown in FIG. 4, converter 103 and battery 101 are collectively referred to as “power storage unit 121”. Further, the internal combustion engine 109, the generator 111, and the second inverter 113 are collectively referred to as a “power generation unit 123”. Further, the first inverter 105 and the electric motor 107 are collectively referred to as a “drive unit 125”. It is assumed that there is no energy transmission loss between each part.

(First embodiment)
5 and 6 are flowcharts showing a method of controlling the internal combustion engine 109 by the management ECU 119 of the first embodiment. As shown in FIG. 5 and FIG. 6, the required driving force calculation unit 201 requests the electric motor 107 based on the AP opening, and the rotational speed (motor rotational speed NE) and torque (motor torque Tr) of the electric motor 107. The output (hereinafter referred to as “required driving force”) Pr is calculated (step S101). Based on the required driving force Pr and the driving unit efficiency m, the driving unit required output calculation unit 203 outputs (hereinafter referred to as “driving unit required output”) Mr requested from the driving unit 125 according to the following equation (1). Is calculated (step S103).
Mr = Pr / m (1)

  The power generation unit output possibility determination unit 205 determines whether the power generation unit 123 can output the drive unit required output Mr based on the characteristics of the internal combustion engine 109 and the generator 111 (step S105). When the drive unit required output Mr can be output, the process proceeds to step S107, and when it cannot be output, the process proceeds to step S109. In step S107, the internal combustion engine operating point deriving unit 215 uses the map based on the output-target NE graph shown in FIG. 7 and the graph showing the characteristics relating to the thermal efficiency of the internal combustion engine 109 shown in FIG. A target operating point of the corresponding internal combustion engine 109 is derived.

On the other hand, in step S109, the power storage unit required output calculation unit 207 determines the following equation (2) based on the drive unit required output Mr and the actual output of the power generation unit 123 (hereinafter referred to as “actual power generation unit output”) Gc. Thus, an output (hereinafter referred to as “required output of power storage unit”) Br required for the power storage unit 121 is calculated.
Br = Mr-Gc (2)

  After step S109, the power storage unit output possibility determination unit 209 detects information such as the temperature, internal resistance, voltage between terminals, input / output current, and remaining capacity (SOC: State of Charge) of the battery 101 (step S111). Next, the power storage unit output possibility determination unit 209 determines whether or not the power storage unit 121 can output the power storage unit required output Br based on at least one of these pieces of information acquired in step S109. Is determined (step S113). Note that the management ECU 119 limits the output of the power storage unit 121 to a predetermined value or less so that no overcurrent flows through the power storage unit 121. Further, when the SOC of the battery 101 is less than a predetermined level, or when the temperature of the battery 101 is less than a predetermined value, the management ECU 119 controls the output of the power storage unit 121 so that the battery 101 does not overdischarge. Thus, the output of the power storage unit 121 is limited according to the state of the battery 101 and the like.

  If it is determined in step S113 that the power storage unit 121 can output the power storage unit required output Br, the process proceeds to step S115. If it is determined that the power storage unit required output Br cannot be output, the process proceeds to step S117. In step S115, the internal combustion engine operating point deriving unit 215 uses the map based on the output-target NE graph shown in FIG. 7 and the graph showing the characteristics relating to the thermal efficiency of the internal combustion engine 109 shown in FIG. A target operating point of the corresponding internal combustion engine 109 is derived.

  On the other hand, in step S117, the corrected power generation unit output calculation unit 211 determines the difference between the drive unit required output Mr and the output possible by the power storage unit 121 (hereinafter referred to as “power storage unit possible output”) Bp (drive unit required output Mr−power storage unit). The possible output Bp) is calculated as the corrected power generation unit output Ga. Next, the combustion control value deriving unit 213 calculates the difference between the power storage unit required output Br and the power storage unit possible output Bp (power storage unit required output Br−power storage unit possible output Bp) as the power storage unit output limit amount Bl (step S119). ).

  Next, the combustion control value deriving unit 213 uses the introduction amount of EGR as a target combustion control value of the internal combustion engine 109 according to the rotational speed NEg of the generator 111, the corrected power generation unit output Ga, and the power storage unit output limit amount Bl. A certain target EGR value is derived (step S121). The target EGR value is derived only when a predetermined condition is satisfied. The predetermined conditions are that the air-fuel ratio feedback control (Air-Fuel Ratio feedback control) is in operation, that the engine water temperature is above a predetermined value, that the fuel is not being cut, and that the engine is not in the engine start mode. .

  FIG. 9 is a conceptual diagram showing a process for deriving a target EGR value by the combustion control value deriving unit 213. As shown in FIG. 9, the combustion control value deriving unit 213 derives a target EGR basic value EGRs according to the corrected power generation unit output Ga using the basic EGR map. In this process, different basic EGR maps are used according to the rotational speed NEg of the generator 111. Combustion control value deriving unit 213 derives a correction coefficient corresponding to power storage unit output limit amount Bl using the correction coefficient map. As shown in FIG. 9, the correction coefficient decreases as the power storage unit output limit amount B1 increases. The combustion control value deriving unit 213 derives a target EGR value by multiplying the target EGR basic value EGRs by a correction coefficient.

  Next, the internal combustion engine operating point derivation unit 215 uses the map based on the corrected power generation unit output-target NE graph shown in FIG. 10 and the graph showing the characteristics relating to the thermal efficiency of the internal combustion engine 109 shown in FIG. A target operating point of the internal combustion engine 109 is derived according to Ga and the power storage unit output limit amount Bl (step S123). As shown in FIG. 10, the target rotational speed of internal combustion engine 109 with respect to corrected power generation unit output Ga varies depending on power storage unit output limit amount Bl. As shown in FIG. 11, even if the target rotational speed is the same, the target operating point of the internal combustion engine 109 differs depending on the power storage unit output limit amount Bl.

  The management ECU 119 controls the internal combustion engine 109 to operate the internal combustion engine 109 at the target operating point derived as described above and to perform EGR according to the target EGR value when the target EGR value is derived.

  As described above, according to the present embodiment, when the HEV is traveling in series, when the output of the power generation unit 123 is required because the battery 101 cannot output the requested output, the power storage unit output limit amount Bl is set. A corresponding amount of EGR is performed, and the internal combustion engine 109 is driven at an operating point corresponding to the EGR amount. When EGR is performed, the output responsiveness of the internal combustion engine 109 is increased, so that the followability of the power generation unit 123 with respect to the required output to the power generation unit 123 can be ensured. Therefore, it is possible to prevent the drivability from decreasing due to the output limitation or the output decrease of the battery 101.

(Second embodiment)
In the second embodiment, the combustion control value deriving unit 213 derives a target INV (In-Valve close timing) value as the target combustion control value of the internal combustion engine 109 in step S121 of the flowchart shown in FIG. The INV value indicates the degree of slow closing of the intake valve in the internal combustion engine 109. The management ECU 119 performs Atkinson control according to the target INV value for the internal combustion engine 109. Except for this point, the second embodiment is the same as the first embodiment.

  The target INV value is derived only when a predetermined condition is satisfied. The predetermined conditions are that the air-fuel ratio feedback control is operating, the engine water temperature is equal to or higher than a predetermined value, and that the engine start mode is not being performed.

  FIG. 12 is a conceptual diagram showing a process for deriving a target INV value by the combustion control value deriving unit 213. As shown in FIG. 12, the combustion control value deriving unit 213 derives a target INV basic value INVs corresponding to the corrected power generation unit output Ga using the basic INV map. In this process, different basic INV maps are used depending on the rotational speed NEg of the generator 111. Combustion control value deriving unit 213 derives a correction coefficient corresponding to power storage unit output limit amount Bl using the correction coefficient map. As shown in FIG. 12, the correction coefficient is smaller as the power storage unit output limit amount B1 is larger. The combustion control value deriving unit 213 derives the target INV value by multiplying the target INV basic value INVs by a correction coefficient.

  As described above, according to the present embodiment, when the HEV is traveling in series, when the output of the power generation unit 123 is required because the battery 101 cannot output the requested output, the power storage unit output limit amount Bl is set. The timing control for delaying the closing of the intake valve of the internal combustion engine 109 is performed, and the internal combustion engine 109 is driven at an operating point corresponding to the delay closing amount. Since the output responsiveness of the internal combustion engine 109 is increased by reducing the slow closing amount of the intake valve of the internal combustion engine 109, the followability of the power generation unit 123 with respect to the required output to the power generation unit 123 can be ensured. Therefore, it is possible to prevent the drivability from decreasing due to the output limitation or the output decrease of the battery 101.

(Third embodiment)
In the third embodiment, the combustion control value deriving unit 213 derives the lean operation determination value as the target combustion control value of the internal combustion engine 109 in step S121 of the flowchart shown in FIG. The lean operation determination value indicates whether the lean operation in the internal combustion engine 109 that makes the air-fuel mixture thinner than the stoichiometric air-fuel ratio is permitted or prohibited. Combustion control value deriving unit 213 derives a lean operation determination value that permits lean operation if power storage unit output limit amount Bl is less than a predetermined value, and prohibits lean operation if it is greater than or equal to a predetermined value. The management ECU 119 controls the internal combustion engine 109 to perform lean operation when the lean operation determination value indicates permission of lean operation, and performs the stoichiometric operation or rich operation when the lean operation determination value indicates prohibition of lean operation. The internal combustion engine 109 is controlled. Except for this point, the second embodiment is the same as the first embodiment.

  The lean operation determination value is derived only when a predetermined condition is satisfied. The predetermined conditions are that the air-fuel ratio feedback control is operating, that the engine water temperature is equal to or higher than a predetermined value, that the engine start mode is not being performed, and that a load range in which lean operation is possible is established.

  As described above, according to the present embodiment, when the HEV is traveling in series, when the output of the power generation unit 123 is required because the battery 101 cannot output the requested output, the power storage unit output limit amount Bl is set. In response, control for permitting or prohibiting the lean operation of the internal combustion engine 109 is performed. Compared to the lean operation, the output responsiveness of the internal combustion engine 109 is increased by performing the stoichiometric operation or the rich operation, so that the followability of the power generation unit 123 to the required output to the power generation unit 123 can be ensured. Therefore, it is possible to prevent the drivability from decreasing due to the output limitation or the output decrease of the battery 101.

  In the above embodiment, the EGR control is controlled in the first example, the Atkinson control is controlled in the second example, and the air-fuel ratio adjustment control is controlled in the third example. May be controlled.

  In the above-described embodiment, an example in which the hybrid vehicle control device according to the present invention is included in a series HEV has been described. However, the hybrid vehicle control apparatus may be included in a parallel HEV or a series / parallel HEV.

101 Battery (BATT)
103 Converter (CONV)
105 1st inverter (1st INV)
107 Electric motor (Mot)
109 Internal combustion engine (ENG)
111 Generator (GEN)
113 Second inverter (second INV)
115 Gearbox 119 Management ECU (MG ECU)
121 power storage unit 123 power generation unit 125 drive unit 201 required driving force calculation unit 203 drive unit required output calculation unit 205 power generation unit output capability determination unit 207 power storage unit required output calculation unit 209 power storage unit output capability determination unit 211 corrected power generation unit output calculation unit 213 Combustion control value deriving unit 215 Internal combustion engine operating point deriving unit

Claims (8)

A power generation unit having an internal combustion engine and a generator that generates power by operation of the internal combustion engine;
A power storage unit having a capacitor for supplying electric power to an electric motor that is a drive source of the hybrid vehicle;
A drive unit having the electric motor driven by power supply from at least one of the power storage unit and the generator, and a control device for the hybrid vehicle comprising:
A drive unit required output deriving unit for deriving an output required for the drive unit according to an accelerator pedal opening and a state of the electric motor according to an accelerator operation in the hybrid vehicle;
Based on the characteristics of the power generation unit, a power generation unit output enable determination unit that determines whether the power generation unit can output an output corresponding to the output requested of the drive unit;
When it is determined that the power generation unit cannot output an output corresponding to the output requested of the drive unit, based on the information on the battery, the difference between the output requested of the drive unit and the output of the power generation unit A power storage unit output enable determination unit that determines whether the power storage unit can output a certain power storage unit required output; and
When it is determined that the power storage unit cannot output the power storage unit required output, a corrected power generation unit output that is a difference between an output requested by the drive unit and an output that the power storage unit is capable of, and the power storage unit required output A combustion control value deriving unit for deriving a parameter related to combustion control of the internal combustion engine according to a power storage unit output limit amount that is a difference in output that is possible for the battery;
An internal combustion engine operating point deriving unit for deriving a target operating point of the internal combustion engine according to the corrected power generation unit output and the power storage unit output limit amount;
A control apparatus for a hybrid vehicle, comprising: The hybrid vehicle control device according to claim 1,
The combustion control value deriving unit
Deriving a parameter related to combustion control of the internal combustion engine by multiplying a basic parameter related to combustion control of the internal combustion engine according to the corrected power generation unit output by a correction coefficient corresponding to the power storage unit output limit amount A hybrid vehicle control device. The hybrid vehicle control device according to claim 1 or 2,
The control apparatus for a hybrid vehicle, wherein the combustion control of the internal combustion engine is EGR control, Atkinson control, air-fuel ratio adjustment control, or a combination of these controls. A control device for a hybrid vehicle according to claim 3,
When the combustion control of the internal combustion engine is EGR control,
The parameter relating to the combustion control of the internal combustion engine indicates the amount of EGR introduced,
The control apparatus for a hybrid vehicle, wherein the correction coefficient is smaller as the power storage unit output limit amount is larger. A control device for a hybrid vehicle according to claim 3,
When the combustion control of the internal combustion engine is Atkinson control,
The parameter relating to the combustion control of the internal combustion engine indicates the degree of slow closing of the intake valve in the internal combustion engine,
The control apparatus for a hybrid vehicle, wherein the correction coefficient is smaller as the power storage unit output limit amount is larger. A control device for a hybrid vehicle according to claim 3,
When the combustion control of the internal combustion engine is air-fuel ratio adjustment control,
The parameter relating to combustion control of the internal combustion engine indicates permission of lean operation of the internal combustion engine if the power storage unit output limit amount is less than a predetermined value, and if the power storage unit output limit amount is equal to or greater than the predetermined value, A control device for a hybrid vehicle, which indicates prohibition of lean operation of an internal combustion engine. A control device for a hybrid vehicle according to any one of claims 1 to 6,
The control apparatus for a hybrid vehicle, wherein the internal combustion engine operating point deriving unit derives a target operating point having a higher rotational speed as the power storage unit output limit amount increases. A power generation unit having an internal combustion engine and a generator that generates power by operation of the internal combustion engine;
A power storage unit having a capacitor for supplying electric power to an electric motor that is a drive source of the hybrid vehicle;
A drive unit having the electric motor driven by power supply from at least one of the power storage unit and the generator, and a control method for the hybrid vehicle comprising:
According to the accelerator pedal opening and the state of the electric motor according to the accelerator operation in the hybrid vehicle, the output required for the drive unit is derived,
Based on the characteristics of the power generation unit, determine whether the power generation unit can output an output corresponding to the output requested of the drive unit,
When the power generation unit determines that the output corresponding to the output requested by the drive unit cannot be output, it is a difference between the output requested by the drive unit and the output of the power generation unit based on information on the battery Determine whether the power storage unit can output the power storage unit required output,
When it is determined that the power storage unit cannot output the power storage unit required output, a corrected power generation unit output that is a difference between the output requested by the drive unit and the power storage unit is possible, and the power storage unit required output and Deriving parameters related to combustion control of the internal combustion engine according to the power storage unit output limit amount, which is a difference in output that can be performed by the battery,
A control method for a hybrid vehicle, wherein a target operating point of the internal combustion engine is derived according to the corrected power generation unit output and the power storage unit output limit amount.

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