WO2014167413A1

WO2014167413A1 - Hybrid vehicle

Info

Publication number: WO2014167413A1
Application number: PCT/IB2014/000560
Authority: WO
Inventors: Kazuma Aoki; Koji HOKOI; Hiroki Endo
Original assignee: Toyota Jidosha Kabushiki Kaisha
Priority date: 2013-04-08
Filing date: 2014-04-08
Publication date: 2014-10-16
Also published as: JP2014201245A

Abstract

A hybrid vehicle includes an engine (22); a motor (MG1, MG2) that generates electric power using power from the engine (22); a battery (50) that transmits and receives electric power to and from the motor (MG1, MG2); and a control unit (24, 40, 70) configured to control the engine (22) and the motor (MG1, MG2) so that a power storage amount of the battery is increased at an indicated increase rate, in response to an instruction to promote charging of the battery and an instruction indicating the increase rate of the power storage amount of the battery.

Description

HYBRID VEHICLE

BACKGROUND OF THE INVENTION 1. Field of the Invention

[0001] The present invention relates to a hybrid vehicle, and more particularly, to a hybrid vehicle including an engine, a motor that generates electric power using power from the engine, and a battery that transmits and receives electric power to and from the motor.

2. Description of Related Art

[0002] As this type of hybrid vehicle in related art, a hybrid vehicle has been proposed which includes an engine, a first motor-generator generating electric power using the engine as a power source, a second motor-generator driving the vehicle, and a battery being charged with electric power generated by the first motor-generator and supplying electric power to the second motor-generator and in which when the battery is charged with the electric power generated by the first motor-generator, the power generation time is increased when a "+" lever of a paddle shift is pressed after the charging is started, the power generation time is decreased when a "-" lever is pressed, and the charging of the battery is performed with the power generation time increased or decreased in this manner (for example, see Japanese Patent Application Publication No. 2012-46121 (JP 2012-46121 A)). In this vehicle, the battery can be charged within a desired time through this control.

[0003] However, in a hybrid vehicle including an engine outputting power for traveling, a motor receiving and outputting the power for traveling, and a battery transmitting and receiving electric power to and from the motor, for example, in a case where a destination is a region in which only a vehicle not discharging exhaust gas at all can be allowed to run, a user may request a power storage amount of the battery to reach a target power storage amount at the destination in preparation for a motor running operation in which the vehicle runs with only the power from the motor without operating the engine. As a technique of dealing with such a user's request, a technique is conceivable in which the engine or the motor is controlled so that the power storage amount of the battery reaches the target power storage amount when a user requests the battery to be charged. However, in such a technique, when an increase rate, at which the power storage amount of the battery is increased, is low, the vehicle may arrive at the destination before the power storage amount reaches the target power storage amount.

SUMMARY OF THE INVENTION

[0004] An object of a hybrid vehicle according to the present invention is to increase a power storage amount of a battery at an increase rate desired by a user, in response to an instruction to promote charging of the battery.

[0005] An aspect of the present invention relates to a hybrid vehicle that includes an engine; a motor that generates electric power using power from the engine; a battery that transmits and receives the electric power to and from the motor; and a control unit configured to control the engine and the motor so that a power storage amount of the battery is increased at an indicated increase rate, in response to an instruction to promote charging of the battery and an instruction indicating the increase rate of the power storage amount of the battery.

[0006] In the hybrid vehicle according to the above-mentioned aspect of the present invention, the engine and the motor are controlled so that the power storage amount of the battery is increased at the indicated increase rate, in response to the instruction to promote the charging of the battery and the instruction indicating the increase rate of the power storage amount of the battery. Thus, it is possible to increase the power storage amount of the battery at the increase rate desired by a user, in response to the instruction to promote the charging of the battery.

[0007] In the hybrid vehicle according to the above-mentioned aspect, the increase rate of the power storage amount of the battery may be indicated by indicating a necessary charging time until the power storage amount of the battery reaches a target power storage amount; and the increase rate may be a rate at which the power storage amount is increased so as to reach the target power storage amount at or after a time at which the necessary charging time elapses after the instruction to promote the charging is provided. Thus, the power storage amount of the battery may be caused to reach the target power storage amount at a timing closer to the timing desired by the user. In this case, the control unit may be configured to control the engine so that the engine outputs power corresponding to a sum of running required power and power obtained by limiting charging required power by using an upper-limit charging power, the running required power being power required for running, the charging required power being power required for charging the battery to make the power storage amount equal to the target power storage amount, and the upper-limit charging power being an upper limit value of permissible electric power permitted for charging the battery. Thus, it is possible to cause the power storage amount of the battery to reach the target power storage amount by charging the battery with the power from the engine.

[0008] The hybrid vehicle according to the aspect of the present invention in which the target power storage amount and the necessary charging time is indicated by a user may further include a notification unit that notifies information, wherein the control unit is configured to control the notification unit so that the notification unit notifies an estimated necessary time in response to the instruction to promote the charging of the battery, the estimated necessary time being an estimated value of a necessary time until the power storage amount reaches the target power storage amount after the instruction to promote the charging of the battery is provided. Thus, it is possible to prevent the user from feeling discomfort when the power storage amount does not reach the target power storage amount within the necessary charging time indicated by the user.

[0009] In the hybrid vehicle according to the aspect of the present invention that includes the notification unit, the control unit may be configured to compute the estimated necessary time using the necessary charging time that is input, estimated running power that is an estimated value of the running required power until the power storage amount of the battery reaches the target power storage amount, and power obtained by limiting average charging power by using the upper-limit charging power, the average charging power being an average value of power for charging the battery until the power storage amount of the battery reaches the target power storage amount. In this case, the estimated running power may be set to an average value of the running required power in a period of time from an ignition switch is turned on until the ignition switch is turned off before the instruction to promote the charging of the battery is provided.

[0010] In the hybrid vehicle according to the aspect of the present invention including a notification unit, the notification unit may visually display the information.

[0011] The hybrid vehicle according to the above-mentioned aspect of the present invention may further include an external power supply device that supplies electric power from the battery to an external device when the external device is connected to the external power supply device.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Features, advantages, and technical and industrial significance of exemplary embodiments of the invention will be described below with reference to the accompanying drawings, in which like numerals denote like elements, and wherein:

FIG. 1 is a diagram schematically illustrating a configuration of a hybrid vehicle 20 according to an embodiment of the present invention;

FIG 2 is a flowchart illustrating an example of a switch-on processing routine which is performed by an HVECU 70 according to the embodiment;

FIG 3 is a diagram illustrating an example of a target value selection screen

; displayed on a touch panel 98;

FIG. 4 is a diagram illustrating an example of a temporary charging-discharging required power setting map;

FIG. 5 is a flowchart illustrating an example of an estimated necessary time displaying process;

FIG 6 is a diagram illustrating an example of a state where an estimated necessary time tend is displayed on the touch panel 98;

FIG 7 is a diagram schematically illustrating a configuration of a hybrid vehicle 120 according to a modification example; FIG. 8 is a diagram schematically illustrating a configuration of a hybrid vehicle 220 according to another modification example;

FIG. 9 is a diagram schematically illustrating a configuration of a hybrid vehicle 320 according to another modification example; and

FIG 10 is a diagram schematically illustrating a configuration of a hybrid vehicle 420 according to another modification example.

DETAILED DESCRIPTION OF EMBODIMENTS

[0013] Hereinafter, embodiments of the present invention will be described.

[0014] FIG. 1 is a diagram schematically illustrating a configuration of a hybrid vehicle 20 according to a first embodiment of the present invention. As illustrated in FIG. 1, the hybrid vehicle 20 according to the first embodiment includes an engine 22 that outputs power using fuel such as gasoline or light oil, an engine electronic control unit (hereinafter, referred to as engine ECU) 24 that controls driving of the engine 22, a single pinion type planetary gear 30 whose carrier is connected to a crank shaft 26 of the engine 22 and whose ring gear is connected to a drive shaft 36 connected to drive wheels 38a, 38b via a differential gear 37, a motor MG1 which is configured, for example, as a synchronous generator-motor and whose rotor is connected to a sun gear of the planetary gear 30, a motor MG2 which is configured, for example, as a synchronous generator-motor and whose rotor is connected to the drive shaft 36, inverters 41, 42 that drive the motors MG1, MG2, a motor electronic control unit (hereinafter, referred to as motor ECU) 40 that controls driving of the motors MG1, MG2 by controlling switching of switching elements (not illustrated) of the inverters 41, 42, a high- voltage battery 50 that is configured, for example, as a lithium-ion secondary battery and that transmits and receives electric power to and from the motors MG1, MG2 via the inverters 41, 42, a battery electronic control unit (hereinafter, referred to as battery ECU) 52 that manages the high-voltage battery 50, a charger 60 that is connected to an external power source such as a household power source and that charges the high-voltage battery 50, a receptacle 94 into which a plug of an external device (for example, a household electronic product) other than elements of the vehicle is inserted, and a DC/AC converter 96 that converts DC power of a power line 54 connected to the inverters 41, 42 and the high-voltage battery 50 into AC power of a predetermined voltage (for example, 100 V) and supplies the AC power to the receptacle 94 (external device) when the plug of the external device is inserted into the receptacle 94, a touch panel 98 that displays input image information and that senses a touched screen position and outputs information signal when a user touches an image displayed on a screen with a finger or a dedicated pen, and a hybrid electronic control unit (hereinafter, referred to as HVECU) 70 that controls the vehicle as a whole. The receptacle 94 and the DC/AC converter 96 correspond to the "external power supply device" of the present invention.

port, signals from various sensors for detecting a state of the engine 22, for example, a crank position from a crank position sensor for detecting a rotation position of the crank shaft 26, a coolant temperature Tw from a coolant sensor for detecting a temperature of a coolant of the engine 22, a throttle position from a throttle valve position sensor for detecting a position of a throttle valve, and an intake air quantity Qa from an air flow meter attached to an intake pipe. The engine ECU 24 outputs, via the output port, various control signals for driving the engine 22, for example, a drive signal for a fuel injection valve, a drive signal for a throttle motor for adjusting the position of the throttle valve, and a control signal for an ignition coil. The engine ECU 24 communicates with the HVECU 70, controls the operating of the engine 22 in accordance with the control signal from the HVECU 70, and outputs data on the operating state of the engine 22 if necessary. The engine ECU 24 computes a rotation speed of the crank shaft 26, that is, a rotating speed Ne of the engine 22, on the basis of the crank position from the crank position sensor.

[0016] The motor ECU 40 is configured as a microprocessor including a CPU (not illustrated) as a main component. The motor ECU 40 includes a ROM that stores a processing program, a RAM that temporarily stores data, input and output ports, and a communication port in addition to the CPU. The motor ECU 40 receives, via the input port, signals necessary for controlling driving of the motors MGl, MG2, for example, rotation positions 0ml, 0m2 from rotation position sensors 43, 44 for detecting rotation positions of the rotors of the motors MGl, MG2, and phase currents applied to the motors MGl, MG2 and detected by current sensors (not illustrated). The motor ECU 40 outputs, via the output port, switching control signals or the like for switching elements (not illustrated) of the inverters 41, 42. The motor ECU 40 communicates with the HVECU 70, controls the driving of the motors MGl, MG2 in accordance with the control signal from the HVECU 70, and outputs data on the operating states of the motor MGl, MG2 to the HVECU 70 if necessary. The motor ECU 40 computes rotational angular velocities ωιηΐ, ωπι2 and rotation speeds Nml, Nm2 of the motors MGl, MG2 on the basis of the rotation positions 0ml, 0m2 of the rotors of the motors MGl, MG2 from the rotation position sensors 43, 44.

[0017] The battery ECU 52 is configured as a microprocessor including a CPU

(not illustrated) as a main component. The battery ECU 52 includes a ROM that stores a processing program, a RAM that temporarily stores data, input and output ports, and a communication port in addition to the CPU. The battery ECU 52 receives signals necessary for managing the high-voltage battery 50, for example, an inter-terminal voltage Vb from a voltage sensor 51a installed between the terminals of the high- voltage battery 50, a charging and discharging current lb from a current sensor 51b fitted to a power line connected to the output terminal of the high- voltage battery 50, and a battery temperature Tb from a temperature sensor 51c fitted to the high- voltage battery 50. The battery ECU 52 transmits data on the state of the high-voltage battery 50 to the HVECU 70 by communications, if necessary. In order to manage the high-voltage battery 50, the battery ECU 52 computes a power storage ratio (state of charge) SOC, which is a ratio of the power which can be discharged from the high-voltage battery 50 at that time, to the total capacity on the basis of the accumulated value of the charging and discharging current lb detected by the current sensor 51b, and computes input and output limit values Win and Wout which are permissible input power with which the high-voltage battery 50 can be charged and permissible output power that can be discharged from the high-voltage battery 40, on the basis of the computed power storage ratio SOC and the battery temperature Tb. The input and output limit values Win and Wout of the high-voltage battery 50 can be set by setting basic values of the input and output limit values Win and Wout on the basis of the battery temperature Tb, setting an output-limit correction coefficient and an input-limit correction coefficient on the basis of the power storage ratio SOC of the high-voltage battery 50, and multiplying the basic values of the set input and output limit values Win and Wout by the correction coefficients.

[0018] The charger 60 is connected to a high-voltage power line 54a via a relay

62 and includes an AC DC converter 66 converting AC power supplied from an external power source via a power supply plug 68 into DC power, and a DC/DC converter 64 converting the voltage of the DC power from the AC/DC converter 66 and supplying the DC power whose voltage has been converted, to the high- voltage power line 54a.

[0019] The HVECU 70 is configured as a microprocessor including a CPU as a main component. The HVECU 70 includes a ROM that stores a processing program, a RAM that temporarily stores data, input and output ports, and a communication port in addition to the CPU. The HVECU 70 receives, via the input port, an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 for detecting an operation position of a shift lever 81, an accelerator operation amount Acc from an acceleration pedal position sensor 84 for detecting a depression amount of an accelerator pedal 83, a brake pedal position BP from a brake pedal position sensor 86 for detecting a depression amount of a brake pedal 85, a vehicle speed V from a vehicle speed sensor 88, an outside air temperature Tout from an outside air temperature sensor 89, an SOC recovery instruction signal indicating ON/OFF of ah SOC recovery instruction switch 90, and information signal from the touch panel 98. The HVECU 70 outputs image information to the touch panel 98. As described above, the HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via a communication port, and transmits and receives various control signals or data to and from the engine ECU 24, the motor ECU 40, and the battery ECU 52. The shift position SP includes a parking position (P position), a neutral position (N position), a drive position for forward running (D position), and a reverse position for backward running (R position).

[0020] In the hybrid vehicle 20 according to the embodiment having the above-mentioned configuration, a required torque Tr* to be output to the drive shaft 36 is calculated on the basis of the accelerator operation amount Acc corresponding to the depression amount of the accelerator pedal depressed by a driver and the vehicle speed V, and operations of the engine 22, the motor MG1, and the motor MG2 are controlled so as to output required power corresponding to the required torque Tr* to the drive shaft 36. Modes of the operation control on the engine 22, the motor MGl, and the motor MG2 include a torque conversion operation mode in which the operation of the engine 22 is controlled so that power corresponding to the required power is output from the engine 22 and the operations of the motor MG1 and the motor MG2 are controlled so that the entire power output from the engine 22 is subjected to torque conversion through the use of the planetary gear 30, the motor MGl, and the motor MG2 and the torque-converted power is output to the drive shaft 36; a charging-discharging operation mode in which the operation of the engine 22 is controlled so that power corresponding to the sum of the required power and the power necessary for charging and discharging of the high- voltage battery 50 is output from the engine 22 and the operations of the motor MGl and the motor MG2 are controlled so that charging or discharging of the high- voltage battery 50 is performed, all or a part of the power output from the engine 22 is subjected to torque conversion by the planetary gear 30, the motor MGl, and the motor MG2, and the required power is output to the drive shaft 36; and a motor operation mode in which the operation of the engine 22 is stopped and the operation is controlled so that the power corresponding to the required power is output from the motor MG2 to the drive shaft 36. The torque conversion operation mode and the charging-discharging operation mode are modes in which the engine 22, the motor MGl, and the motor MG2 are controlled so as to output the required power to the drive shaft 36 with the operation of the engine 22 and have no substantial difference in control therebetween. Thus, both of the torque conversion operation mode and the charging-discharging operation mode are collectively referred to as an engine operation mode.

[0021] In the hybrid vehicle 20 according to the embodiment, when the system of the vehicle is stopped at home or a predetermined charging point, and then the power supply plug 68 is connected to an external power source, and the connection is detected by a connection sensor 69, a system main relay 55 and a relay 62 are turned on and the charger 60 is controlled to charge the high-voltage battery 50 with power from the external power source. When the high-voltage battery 50 is charged and then the system is started, a motor-running priority mode is employed until the power storage ratio SOC of the high-voltage battery 50 becomes equal to a threshold value Shv (for example, 20% or 30%) set to a value at which the engine 22 can be started. In the motor-running priority mode, a motor-running operation in which the vehicle runs using only the power from the motor MG2 has priority over a hybrid-running operation in which the vehicle runs using the power from the engine 22 and the power from the motor MG2. At or after the time at which the power storage ratio SOC of the high-voltage battery 50 becomes equal to the threshold value Shv, a hybrid-running priority mode is employed. In the hybrid-running priority mode, the hybrid-running operation has priority over the motor-running operation.

[0022] In the motor-running priority mode, a required torque Tr*(to be output to the drive shaft 36) required for running is set on the basis of the accelerator operation amount Acc corresponding to the depression amount of the accelerator pedal 83 and the vehicle speed V, and running power Pdrv* required for running is calculated by multiplying the set required torque Tr* by the rotation speed Nr of the drive shaft 36 (for example, the rotation speed Nm2 of the motor MG2 or the rotation speed obtained by multiplying the vehicle speed V by a conversion coefficient). Then, when the running power Pdrv* is equal to or less than the output limit value Wout of the high- voltage battery 50, the motor MG2 is controlled so that the running power Pdrv* is output from the motor MG2 in a state where the operation of the engine 22 is stopped and the required torque Tr* is output to the drive shaft 36, and thus, the hybrid vehicle 20 runs in the motor-running operation. When the running power Pdrv* becomes greater than the output limit value Wout of the high-voltage battery 50, the engine 22 is started and the engine 22 and the motors MG1, MG2 are controlled so that the running power Pdrv* is set as the required power Pe* to be output from the engine 22, the required power Pe* is output from the engine 22, and the required torque Tr* is output to the drive shaft 36, and thus, the hybrid vehicle 20 runs in the hybrid-running operation. Thereafter, when the running power Pdrv* becomes equal to or less than the output limit value Wout of the high-voltage battery 50, the operation of the engine 22 is stopped, and the motor-running operation in which the running power Pdrv* is output from the motor MG2 is performed again.

[0023] In the hybrid-running priority mode, charging-discharging required power Pb* (which has a negative value when it is discharged from the high-voltage battery 50) of the high- voltage battery 50 is set on the basis of the power storage ratio SOC of the high-voltage battery 50, and the running power Pdrv* is added to the set charging-discharging required power Pb* to set the required power Pe* to be output from the engine 22. When the required power Pe* is equal to or greater than a predetermined operation threshold value Pop as the lowest power at which the engine 22 can be relatively efficiently operated, the engine 22, the motor MG1, and the motor MG2 are controlled so that the required power Pe* is output from the engine 22 and the required power Tr* is output to the drive shaft 36, and thus, the hybrid-running operation is performed. When the required power Pe* is less than the operation threshold value Pop, the engine 22 cannot be relatively efficiently operated. Accordingly, the operation of the engine 22 is stopped and the running operation transitions to the motor-running operation in which the running power Pdrv* is output from the motor MG2 for running. When a driver depresses the accelerator pedal 83 while the hybrid vehicle 20 is running in the motor-running operation, the running power Pdrv* increases, and the required power Pe* is equal to or greater than the operation threshold value Pop, the engine 22 is started and the running operation transitions to the hybrid-running operation in which the required power Pe* is output from the engine 22 for running. The operation threshold value Pop is set to a value much smaller than the output limit value Wout of the high- voltage battery 50.

[0024] Operations of the hybrid vehicle 20 according to the embodiment, particularly, operations when the SOC recovery instruction switch 90 is turned on by a user, will be described below. FIG. 2 is a flowchart illustrating an example of a switch-on processing routine which is performed by the HVECU 70. This routine is performed when the SOC recovery instruction switch 90 is turned on by the user. The SOC recovery instruction switch 90 is used to provide an instruction to promote charging of the high-voltage battery 50. The SOC recovery instruction switch 90 may be regarded as "a first device", but the first device is not limited to the SOC recovery instruction switch 90.

[0025] When the SOC recovery instruction switch-on processing routine is performed, the CPU 72 of the HVECU 70 performs a process in which a power storage ratio SOC is input from the battery ECU 52 (step SI 00). Then, screen information on a target value selection screen for setting a target power storage ratio SOC* and a target charging time Tc* is transmitted to the touch panel 98 (step SI 10), and the routine waits until the target power storage ratio SOC* and the target charging time tc* are input from the touch panel 98 (step SI 20). FIG. 3 is a diagram illustrating an example of the target value selection screen displayed on the touch panel 98. Rectangular icons 110 and 111 including characters such as "FULLY CHARGED" and "INTERMEDIATELY CHARGED", an icon 112 including characters indicating the target charging time, and an icon 113 including characters "+" and. "-" are visibly displayed on the touch panel 98. When a user touches one of the displayed icons 110 and 111, the touch panel 98 transmits, to the HVECU 70, information on the state of charge displayed on the touched icon as the target power storage ratio SOC* input by the user, on the basis of the position information of the touched icon. The icon 113 is used to set the time to be displayed in the icon 112. The target time displayed in the icon 112 increases each time the user touches the character of "+" in the icon 113, and the target time displayed in the icon 112 decreases each time the user touches the character of "-" in the icon 113. When a state where the user does not touch the icon 113 is maintained for a predetermined time (for example, 10 seconds), the touch panel 98 transmits the time displayed in the icon 112 as the target charging time tc*, to the HVECU 70. At this time, the color of the icon touched by the user out of the icons 110 and 112 may be changed or the icon as a whole may flicker. The touch panel 98 may be regarded as "a second device", but the second device is not limited to the touch panel 98.

[0026] When the target power storage ratio SOC* and the target charging time tc* are input in this way, an estimated necessary time displaying process to be described later is performed (step SI 30), a power storage ratio change rate s is set by dividing a value, which is obtained by subtracting the current power storage ratio SOC from the input target power storage ratio SOC*, by the target charging time tc* (step SI 40), and a value which is obtained by adding the power storage ratio change rate Ks to a control target power storage ratio SOCc* is set again as the control target power storage ratio SOCc* (step SI 50). The control target power storage ratio SOCc* as an initial value is set to the power storage ratio SOC input in the process of step SI 00.

[0027] After the control target power storage ratio SOCc* is set in this way, a temporary charging-discharging required power Pbtmp for making the power storage ratio SOC equal to the control target power storage ratio SOCc* is set using the power storage ratio SOC and the control target power storage ratio SOCc* of the high- voltage battery 50 and a temporary charging-discharging required power setting map stored in the ROM 74 (step SI 60). An example of the temporary charging-discharging required power setting map is illustrated in FIG. 4. As illustrated in the drawing, when the power storage ratio SOC is greater than the control target power storage ratio SOCc*, the temporary charging-discharging required power Pbtmp is set to power having a negative value so that the absolute value of the temporary charging-discharging required power Pbtmp tends to increase so as to cancel a difference between the control target power storage ratio SOCc* and the power storage ratio SOC, as the difference increases. When the power storage ratio SOC is smaller than the control target power storage ratio SOCc*, the temporary charging-discharging required power Pbtmp is set to power having a positive value so that the absolute value of the temporary charging-discharging required power Pbtmp tends to increase so as to cancel the difference between the control target power storage ratio SOCc* and the power storage ratio SOC, as the difference increases. By setting the temporary charging-discharging required power Pbtmp in this way, the power storage ratio SOC can be changed to the control target power storage ratio SOCc*. The temporary charging-discharging required power setting map is stored in the ROM 74 for each control target power storage ratio SOCc*.

[0028] After the temporary charging-discharging required power Pbtmp is set in this way, one of the temporary charging-discharging required power Pbtmp and an upper-limit charging power Pbmax, which is smaller than the other, is set as the charging-discharging required power Pb* (step SI 70). The upper-limit charging power Pbmax is an upper limit value of the permissible power storage amount of the high- voltage battery 50. After the charging-discharging required power Pb* is set in this way, the engine 22 and the motors MG1, MG2 are controlled so that the hybrid vehicle 20 runs while power, which is obtained by adding the running power Pdrv* to the set charging-discharging required power Pb*, is output from the engine 22 in the hybrid-running priority mode. Accordingly, the hybrid vehicle 20 can run while the high- voltage battery 50 is charged with the electric power generated by the motor MG1 using the power output from the engine 22.

[0029] After the charging-discharging required power Pb* is set in this way, it is determined whether a predetermined ending condition is satisfied. The predetermined ending condition includes, for example, a .condition that the SOC recovery instruction switch 90 is turned off and/or a condition that the power storage ratio SOC of the high-voltage battery 50 becomes equal to the target power storage ratio SOC* (step SI 80). When the predetermined ending condition is not satisfied, the battery ECU 52 inputs the power storage ratio SOC (step SI 90). Then, the routine returns to the process of step SI 50, and the control target power storage ratio SOCc* is set. The processes of steps SI 50 to SI 90 are repeated until the predetermined ending condition is satisfied, the power obtained by adding the power storage ratio change rate Ks to the control target power storage ratio SOCc* is set again as the control target power storage ratio SOCc*, the temporary charging-discharging required power Pbtmp is set using the power storage ratio SOC and the control target power storage ratio SOCc* of the high-voltage battery 50 and the charging-discharging required power setting map stored in the ROM 74, one of the temporary charging-discharging required power Pbtmp and the upper-limit charging power Pbrhax, which is smaller than the other, is set as the charging-discharging required power Pb*, and the power storage ratio SOC is input from the battery ECU 52. Since the high-voltage battery 50 is charged with the power in the range up to the upper-limit charging power Pbmax through these processes, the power storage ratio SOC can be changed to the target power storage ratio SOC*. At this time, the power storage ratio SOC can be changed by the change amount based on the power storage ratio change rate Ks set using the target charging time tc* input by the user. Accordingly, as compared to a case where the power storage ratio SOC approaches the target power storage ratio SOC* immediately when the SOC recovery instruction switch 90 is turned on, it is possible to change the power storage ratio SOC to the target power storage ratio SOC* in the target charging time tc* input by the user and it is thus possible to make the power storage ratio SOC equal to the target power storage ratio SOC* at a timing closer to the timing desired by the user.

[0030] The estimated necessary time displaying process which, is performed in step SI 30 will be described below. FIG. 5 is a flowchart illustrating an example of the estimated necessary time displaying process. In the estimated necessary time displaying process, in order to change the current power storage ratio SOC to the target power storage ratio SOC* in the target charging time tc* (in order to make the current power storage ratio SOC equal to the target power storage ratio SOC*), the power required for charging or discharging of the high-voltage battery 50 per unit time is set as the temporary average charging-discharging power Pbavtmp using Expression (1) (step S200), and the smaller one of the temporary average charging-discharging power Pbavtmp and the upper-limit charging power Pbamx used in the process of step SI 70 is set as average charging-discharging power Pbav (step S210). "Kw" in Expression (1) represents a conversion coefficient for converting the power storage ratio SOC of the high-voltage battery 50 into power.

Pbavtmp = Kw-(SOC*-SOC) / tc... (I

[0031] After the average charging-discharging power Pbav is set in this way, the estimated necessary time tend until the power storage ratio SOC reaches the target power storage ratio SOC* when the vehicle runs with estimated running power Pdav after the SOC recovery instruction switch 90 is turned on is computed by Expression (2) using the target charging time tc*, the average charging-discharging power Pbav, the temporary average charging-discharging power Pbavtmp, and the estimated running power Pdav which is estimated to be average running power of the vehicle when the high-voltage battery 50 is being charged (S220), image information is output to the touch panel 98 so as to display the estimated necessary time tend on the touch panel 98 (step S230), and then this routine ends. FIG. 6 illustrates an example of a state where the estimated necessary time tend is displayed on the touch panel 98. The estimated running power Pdav is the average value of running required power (power required for running) Pdrv* based on the accelerator operation amount Acc and the vehicle speed V in previous one trip from the ignition switch 80 is turned on until it is turned off. Since the high-voltage battery 50 is permitted to be charged with the power in the range up to the upper-limit charging power Pbmax, the actual necessary time until the power storage ratio SOC reaches the target power storage ratio SOC* after the SOC recovery instruction switch 90 is turned on may be different from the target charging time tc* input by the user. When this difference occurs, the charging of the high-voltage battery 50 is not finished in spite of the elapse of the target charging time tc* input by the user, and thus the user may feel discomfort. However, by computing the estimated necessary time tend and displaying the computed estimated necessary time on the touch panel 98, the user can be notified that a difference occurs between the target charging time tc* input by the user and the time in which the charging of the high-voltage battery 50 is actually finished and it is thus possible to prevent the user from feeling discomfort. The average value of running required power Pdrv* in previous one trip from the ignition switch 80 is turned on until it is turned off is used to compute the estimated necessary time tend. Accordingly, it is possible to reflect a user's personal driving habit such as an accelerator operation manner and thus to compute the estimated necessary time tend with high accuracy.

tend = tc* + (Pbavtmp - Pbav)-tc*/(Pdav + Pbav)...(2) [0032] In the above-mentioned hybrid vehicle 20 according to the embodiment, when the SOC recovery instruction switch 90 is turned on, the power storage ratio SOC of the high-voltage battery 50 can be made equal to the target power storage ratio SOC* at a timing closer to the timing desired by the user, by controlling the engine 22 or the motors MG1, MG2 so that the charging-discharging required power Pb* is output from the engine 22. The charging-discharging required power Pb*is set within the range up to the upper-limit charging power Pbmax so that the power storage ratio SOC reaches the target power storage ratio SOC* when the target charging time to* input by the user elapses after the SOC recovery instruction switch 90 is turned on.

[0033] By computing the estimated necessary time tend using the target charging time tc*, the average charging-discharging power Pbav, the temporary average charging-discharging power Pbavtmp, and the estimated running power Pdav and displaying the computed estimated necessary time on the touch panel 98, the user can visually recognize that a difference occurs between the target charging time tc* input by the user and the time in which the charging of the high- voltage battery 50 is actually finished, and it is possible to prevent the user from feeling discomfort due to occurrence of the difference.

[0034] In the hybrid vehicle 20 according to the embodiment, the average value of the running required power Pdrv* based on the accelerator operation amount Acc and the vehicle speed V in previous one trip from the ignition switch 80 is turned on until it is turned off is used as the estimated running power Pdav. However, in a vehicle equipped with a navigation system providing route guidance, the estimated running power Pdav may be computed from road conditions (for example, gradient of a road surface, and a downtown area or a relatively suburban area) from a point at which the SOC recovery instruction switch 90 is turned on to a destination, and/or the running distance.

[0035] In the hybrid vehicle 20 according to the embodiment, the estimated necessary time tend is computed using the target charging time tc*, the average charging-discharging power Pbav, the temporary average charging-discharging power Pbavtmp, and the estimated running power Pdav in the process of step S220. However, the relationship between the target power storage ratio SOC* and the target charging time tc* input by the user, the power storage ratio SOC, and the estimated necessary time tend may be calculated in advance by experiments or analysis and the estimated necessary time tend may be derived from the acquired relationship when the target power storage ratio SOC* and the target charging time tc* are given.

[0036] In the hybrid vehicle 20 according to the embodiment, the processes of step SI 50 and steps subsequent thereto are performed using the power storage ratio change rate Ks set using the target power storage ratio SOC* and the target charging time tc* input by the user in the processes of steps SI 10 to SI 40 of FIG. 2. However, the user may input the power storage ratio change rate Ks instead of the target power storage ratio SOC* and the target charging time tc* and the processes of step S150 and steps subsequent thereto may be performed using the input power storage ratio change rate Ks.

[0037] In the hybrid vehicle 20 according to the embodiment, the estimated necessary time tend is displayed on the touch panel 98. However, the present invention is not limited to the configuration in which the estimated necessary time is displayed on the touch panel 98 and the estimated necessary time may be notified to the user with a sound from a speaker (not illustrated).

[0038] In the hybrid vehicle 20 according to the embodiment, the power from the motor MG2 is output to the drive shaft 36. However, the power from the motor MG2 may be output to an axle (axle connected to vehicle wheels 39a, 39b in FIG. 7) other than the axle (axle connected to drive wheels 38a, 38b) connected to the drive shaft 36, as illustrated in a hybrid vehicle 120 according to a modification example of FIG. 7.

[0039] In the hybrid vehicle 20 according to the embodiment, the power from the engine 22 is output to the drive shaft 36 connected to the drive wheels 38a, 38b via the planetary gear 30. However, a dual-rotor electric motor 230 may be provided which includes an inner rotor 232 connected to the crank shaft of the engine 22 and an outer rotor 234 connected to the drive shaft 36 for outputting the power to the drive wheels 38a, 38b, which transmits a part of the power from the engine 22 to the drive shaft 36, and which converts the rest of the power into electric power, as illustrated in a hybrid vehicle 220 according to a modification example of FIG. 8.

[0040] In the hybrid vehicle 20 according to the embodiment, the power from the engine 22 is output to the drive shaft 36 connected to the drive wheels 38a, 38b via the planetary gear 30 and the power from the motor MG2 is output to the drive shaft 36. However, a so-called series type hybrid vehicle may be employed which includes a motor MG2 for outputting running power and a motor MG1 for generating electric power using the power from the engine 22, as illustrated in a hybrid vehicle 320 according to a modification example of FIG. 9. A hybrid vehicle may be employed which has a configuration in which a motor is attached to the drive shaft 36 connected to the drive wheels 38a, 38b via a continuously variable transmission and the engine 22 is connected to the rotation shaft of the motor via the clutch, the power from the engine 22 is output to the drive shaft via the rotation shaft of the motor and the continuously variable transmissioii and the power from the motor is output to the drive shaft via the continuously variable transmission. The present invention is not limited to a so-called plug-in hybrid vehicle which includes a charger 60 having a DC/DC converter and an AC/DC converter for converting AC power from an external power source into DC power and charging the battery, but may be applied to a hybrid vehicle 420 including an engine 22 and a motor MG1 that are connected to the planetary gear 30 and a motor MG2 capable of outputting and receiving power to and from the drive shaft 36, as illustrated in the hybrid vehicle 420 according to a modification example of FIG. 10.

[0041] In the embodiment, the engine 22 corresponds to the "engine", the motor MG1 and the motor MG2 correspond to the "motor", and the high-voltage battery 50 corresponds to the "battery". The HVECU 70, the engine ECU 24, and the motor ECU 40 correspond to the "control unit". The HVECU 70, the engine ECU 24, and the motor ECU 40 perform the switch-on processing routine in FIG. 2 in which when the SOC recovery instruction switch 90 is turned on, the charging-discharging required power Pb* is set within the range up to the upper-limit charging power Pbmax so that the power storage ratio SOC reaches the target power storage ratio SOC* when the target charging time tc* input by the user elapses after the SOC recovery instruction switch 90 is turned on, and the process in which the engine 22 and the motors MGl, MG2 are controlled so that the power corresponding to the sum of the set charging-discharging required power Pb* and the running required power Pdrv* is output from the engine 22.

[0042] The "engine" is not limited to the engine that outputs power using hydrocarbon-based fuel such as gasoline or light oil, and may be any type of engine such as a hydrogen engine as long as it can output running power. The "motor" is not limited to the motor MGl and the motor MG2 configured as synchronous generator-motors, and may be any type of electric motor such as an induction motor as long as it can generate electric power using the power from the engine. The "battery" is not limited to the high-voltage battery 50 as a secondary battery, and may be any device as long as it can transmit and receive power to and from the motor. The "control unit" is not limited to the combination including the HVECU 70, the engine ECU 24, and the motor ECU 40, and may be configured by a single electronic control unit or the like. The "control unit" is not limited to the control unit that sets the charging-discharging required power Pb* within the range up to the upper-limit charging power Pbmax so that the power storage ratio SOC reaches the target power storage ratio SOC* when the target charging time to* input by the user elapses after the SOC recovery instruction switch 90 is turned on, and that controls the engine 22 and the motors MGl, MG2 so that the power corresponding to the sum of the set charging-discharging required power Pb* and the running required power Pdrv* is output from the engine 22. The "control unit" may be of any type as long as it can control the engine and the motor so that the power storage amount of the battery is increased at an indicated increase rate in response to an instruction to promote charging of the battery, the instruction indicating the increase rate of the power storage amount of the battery.

[0043] While the embodiments of the present invention have been described above, the present invention is not limited to the embodiments and various modifications may be made to the embodiments without departing from the scope of the present invention.

[0044] The present invention is applicable to industries of manufacturing a hybrid vehicle or the like.

Claims

CLAIMS:

1. A hybrid vehicle comprising:

an engine;

a motor that generates electric power using power from the engine;

a battery that transmits and receives the electric power to and from the motor; and a control unit configured to control the engine and the motor so that a power storage amount of the battery is increased at an indicated increase rate, in response to an instruction to promote charging of the battery and an instruction indicating the increase rate of the power storage amount of the battery.

2. The hybrid vehicle according to claim 1, wherein:

the increase rate of the power storage amount of the battery is indicated by indicating a necessary charging time until the power storage amount of the battery reaches a target power storage amount; and

the increase rate is a rate at which the power storage amount is increased so as to reach the target power storage amount at or after a time at which the necessary charging time elapses after the instruction to promote the charging is provided.

3. The hybrid vehicle according to claim 2, wherein the control unit is configured to control the engine so that the engine outputs power corresponding to a sum of running required power and power obtained by limiting charging required power by using an upper-limit charging power, the running required power being power required for running, the charging required power being power required for charging the battery to make the power storage amount equal to the target power storage amount, and the upper-limit charging power being an upper limit value of permissible electric power permitted for charging the battery.

4. The hybrid vehicle according to claim 2 or 3, further comprising a notification unit that notifies information,

wherein the control unit is configured to control the notification unit so that the notification unit notifies an estimated necessary time in response to the instruction to promote the charging of the battery, the estimated necessary time being an estimated value of a necessary time until the power storage amount reaches the target power storage amount after the instruction to promote the charging of the battery is provided.

5. The hybrid vehicle according to claim 4, wherein the control unit is configured to compute the estimated necessary time using the necessary charging time that is input, estimated running power that is an estimated value of the running required power until the power storage amount of the battery reaches the target power storage amount, and power obtained by limiting average charging power by using the upper-limit charging power, the average charging power being an average value of power for charging the battery until the power storage amount of the battery reaches the target power storage amount.

6. The hybrid vehicle according to claim 1, further comprising:

a first device that is operated to provide the instruction to promote the charging of the battery; and

a second device that is operated to provide the instruction indicating the increase rate.