JP6674790B2 - Power supply system and transportation equipment - Google Patents

Description

  The present invention relates to a power supply system that supplies power to an electric load such as an electric motor using two power storage devices.

  2. Description of the Related Art Conventionally, as this type of power supply system, for example, the one shown in Patent Document 1 is known. Patent Literature 1 discloses that power is supplied to an electric motor of a vehicle by using two power storage devices, a high-capacity power storage device and a high-output power storage device having a relatively high output power upper limit. A system configured to obtain is described.

  In this system, charging of a high-capacity power storage device can be performed by an external charging device, but charging of the high-capacity power storage device from the load side (electric motor side) is prevented by a diode. It is supposed to be.

JP 2014-143817 A

  In general, a high-capacity power storage device has lower resistance to deterioration with respect to charging than a high-output power storage device or the like. For this reason, when a high-capacity power storage device is charged (particularly at a high rate), deterioration is likely to occur.

  Therefore, it is desirable that charging of the high-capacity power storage device is not performed as much as possible. In charging, charging is performed at a low rate (low speed) as much as possible, and the progress of deterioration of the power storage device is suppressed as much as possible. It is desirable.

  Here, in the system disclosed in Patent Document 1, although the high-capacity power storage device can be charged by an external charging device, the high-capacity power storage device can be charged from the load side (electric motor side). Charging of the power storage device is prevented by the diode. For this reason, charging of a high-capacity power storage device having low resistance to deterioration with charging is limited to charging by an external charging device, and the regenerative electric power of the electric motor is charged to the high-capacity power storage device while the vehicle is running. Never.

  However, in the system disclosed in Patent Literature 1, for example, when a high-output power storage device breaks down and power cannot be supplied from the power storage device to the electric motor, only the high-capacity power storage device is used. Power is supplied to the electric motor. In this case, since the high-capacity power storage device cannot charge the regenerative power of the electric motor, the remaining capacity of the high-capacity power storage device decreases with power supply to an electric load such as the electric motor. Just do it.

  For this reason, in the system disclosed in Patent Literature 1, when the high-output power storage device fails, power cannot be supplied to the electric motor (the electric loads of the two power storage devices) early after that. Easy to get rid of.

  In addition, in a situation where the high-output type power storage device is almost fully charged, regenerative power of the electric motor cannot be charged to both the high-output type power storage device and the high-capacity type power storage device. Therefore, it is necessary to satisfy a braking request for the electric motor by a braking device such as a brake. As a result, the regenerative power that can be received by the system is reduced, so that the energy efficiency (power consumption) of the entire system is deteriorated.

  The present invention has been made in view of such a background, and even if one of the two power storage devices fails, it is possible to extend the period during which power can be supplied from another power storage device as much as possible. It is an object to provide a power supply system that can be used.

  It is another object of the present invention to provide a transportation device including the power supply system.

The power supply system of the present invention, in order to achieve the above object,
A first power storage device and a second power storage device;
An electric load operable by receiving power supply from at least one of the first power storage device and the second power storage device and capable of outputting regenerative power without receiving the power supply; the first power storage device; A power transmission path is provided between the power storage device and the power storage device, and power transmission between the electric load and the first power storage device and the second power storage device can be controlled according to a given control signal. A power transmission circuit unit configured in
A braking device that generates a braking force applied to the electric load,
A control device having a function of controlling the power transmission circuit unit and the braking device, respectively.
The control device includes:
Failure detection information indicating the presence or absence of a failure in each of the first power storage device and the second power storage device, and a required braking force at the time of braking the electric load, can be acquired;
When the electric load is braked when both the first power storage device and the second power storage device are in a failure-free state, one or both of the first power storage device and the second power storage device are charged with the regenerative power. The power transmission circuit unit and the braking unit are configured to satisfy the required braking force of the electric load by at least one of a regenerative braking force generated thereby and a non-regenerative braking force that is a braking force generated by the braking device. A first braking process that controls at least one of the devices, and includes a process that controls the power transmission circuit unit to charge at least a part of the regenerative power to the second power storage device. Functions to perform,
When the electric load is braked when the first power storage device is in a failure-free state and the second power storage device is in a faulty state, the regenerative power is generated by charging the one power storage device. At least one of the power transmission circuit unit and the braking device is controlled such that a required braking force of the electric load is satisfied by at least one of a regenerative braking force and a non-regenerative braking force generated by the braking device. And a function of executing a second braking process including a process of controlling the power transmission circuit unit to charge the regenerative power only to the first power storage device. the shall be the basic configuration.
In the first invention, the first power storage device is a power storage device having lower deterioration resistance to charging than the second power storage device, and the control device performs the first braking process when braking the electric load. When the regenerative power index value indicating the magnitude of the regenerative power to be output from the electric load is smaller than a predetermined A threshold, the regenerative power is charged only to the first power storage device, and the regenerative power index value is calculated. Is larger than the A-th threshold, the regenerative power is charged to one or both of the first and second power storage devices including at least the second power storage device. The A-th threshold is configured to control a transmission circuit unit, and a range smaller than the A-th threshold is larger than the A-th threshold in the range equal to or less than a maximum value of the regeneration amount index value. To a range smaller than the range Characterized in that it is set to so that.

  Here, the terms related to the present invention will be supplemented. “Regenerative power” means the amount of electricity output from the electric load due to the regenerative operation (power generation operation) of the electric load. In this case, the “electric amount” and the “regenerative power” are represented, for example, by an electric energy amount (for example, electric power value) per unit time or a charge amount (for example, current value) per unit time.

  The “requested braking force” of the electric load means a required value of a braking force to be applied to a movable part (a rotating part, a translation part, and the like) of the electric load.

  In addition, the "braking force" (non-regenerative braking force) generated by the braking device is externally added to a movable portion of the electric load, separately from the regenerative braking force generated by the electric load outputting regenerative power. Braking force (for example, braking force due to frictional force).

  The fact that the “power transmission circuit unit” can control power transmission between the electric load and the first power storage device and the second power storage device means that the “power transmission circuit unit” This means that it has at least a function of controlling the amount of electricity transferred between each of the power storage device and the second power storage device and the electric load.

  Further, the “remaining capacity” indicates the amount of power (for example, the amount of power in units of [Ah]) stored in the power storage device (the first power storage device or the second power storage device) and the full amount of the power storage device. Any of the charging rates [%] obtained by dividing by the charging capacity may be used.

  The present invention will be described on the premise of the above.

According to the above basic configuration , the control device executes the first braking process when braking the electric load when both the first power storage device and the second power storage device are in a failure-free state. Thus, the required braking force is realized by one or both of the regenerative braking force and the non-regenerative braking force.

  In this case, the first braking process includes a process of controlling the power transmission circuit unit to charge at least a part of the regenerative power to the second power storage device. For this reason, a situation occurs in which the second power storage device is charged with the regenerative power during braking of the electric load. As a result, a state where power can be supplied from the second power storage device to the electric load can be maintained as long as possible.

  Further, when braking the electric load in a case where the first power storage device has no failure and the second power storage device has a failure, the control device executes the second braking process. . Thus, the required braking force is realized by one or both of the regenerative braking force and the non-regenerative braking force. However, in this case, since the second power storage device is in a faulty state, generating the regenerative braking force means that the regenerative power is transmitted to the first power storage device of the first power storage device and the second power storage device. It can be realized by charging only.

  Then, the second braking process includes a process of controlling the power transmission circuit unit to charge the regenerative power only to the first power storage device. For this reason, a situation occurs in which the first power storage device is charged by the regenerative power during braking of the electric load. As a result, even when a failure occurs in the second power storage device, a state where power can be supplied from the first power storage device in a failure-free state to the electric load can be maintained as long as possible.

Therefore, according to the first invention, even if one of the two power storage devices fails (second power storage device), power can be supplied from another power storage device (first power storage device) to the electric load. The period can be extended as much as possible .
Further, in the first invention, the first power storage device is a power storage device having lower deterioration resistance to charging than the second power storage device. In the first braking process, when the regenerative amount index value indicating the magnitude of the regenerative power to be output from the electric load during braking of the electric load is smaller than a predetermined A threshold, Charging the regenerative power only to the first power storage device, and when the regenerative amount index value is larger than the A-th threshold value, regenerates the regenerative power to the first power storage device and the second power storage device. The power transmission circuit unit is controlled to charge at least one or both power storage devices including the second power storage device. Further, the A-th threshold value is set such that a range smaller than the A-th threshold value is a range narrower than a range larger than the A-th threshold value, out of a range equal to or less than the maximum value of the regeneration amount index value. ing
According to this, in the first braking process, in a situation where the regenerative electric power is output from the electric load, the regenerative power of the first power storage device per unit time (charging speed) is prevented from increasing as much as possible. It is possible to charge all or part of the power to the first power storage device. As a result, the first power storage device can be charged with regenerative power while suppressing the progress of the deterioration of the first power storage device.
Further, in this case, the second power storage device has a relatively high resistance to deterioration with respect to charging. Therefore, in the first braking process, the second power storage device is prevented from deteriorating while the second power storage device is being deteriorated. The remaining capacity can be quickly increased by the regenerative power.

  In the first invention, the first power storage device is a power storage device having a higher energy density than the second power storage device, and the second power storage device is a power storage device having a higher output density than the first power storage device. It is preferable to have the second invention (second invention).

  According to this, when both the first power storage device and the second power storage device are normal (there is no failure), the energy density of the first power storage device is relatively high, so that power is supplied to the electric load. Can be extended. Further, since the output density of the second power storage device is relatively high, the amount of power supplied to the electric load (supply to the electric load) (The amount of electricity generated) can be changed with high responsiveness.

  Therefore, an energy source in which both the output density and the energy density are increased can be realized by the entirety of the first power storage device and the second power storage device.

  In general, when the remaining capacity of the second power storage device having a relatively high output density is too small or too large, the deterioration of the second power storage device is likely to proceed early, but the electric load of the second power storage device is relatively high. In the first braking process in braking, the second power storage device can be appropriately charged with the regenerative power. Therefore, it is possible to prevent the remaining capacity of the second power storage device from becoming too small or too large, and to suppress the progress of the deterioration of the second power storage device. As a result, the power density of the energy source can be increased so that power can be supplied to the electric load with high responsiveness.

  Supplementally, the “required output” means a value that defines a required value of the amount of electricity required for operating the electric load. As the “required output”, the required value of the quantity of electricity itself can be used. Further, when the electric load generates, for example, a mechanical output (power or kinetic energy) corresponding to the amount of electricity supplied, the required value of the mechanical output is set to “ It can also be used as "request output."

In the basic configuration , in the first braking process, charging the regenerative power to the first power storage device may not be performed. However, in the first braking process, a process of controlling the power transmission circuit unit to charge the regenerative power only to the first power storage device, and a process of charging the regenerative power only to the second power storage device. a process of controlling the power transmission circuit section, has preferably comprise two or more processing among the processing for charging the regenerative power to both of the first power storage device and the second power storage device.
In the first invention, in the first braking process, when a regenerative amount index value indicating the magnitude of the regenerative power to be output from the electric load during braking of the electric load is smaller than a predetermined A threshold, When the regenerative power is charged only to the first power storage device, and when the regenerative amount index value is larger than the A threshold, the regenerative power is transferred to at least a first power storage device of the first power storage device and the second power storage device. The power transmission circuit unit is controlled to charge one or both power storage devices including the two power storage devices.

  According to this, in the first braking process, not only the second power storage device but also the first power storage device can be appropriately charged with the regenerative power. Therefore, it is possible to realize the required braking force at the time of braking of the electric load only by the regenerative braking force, or as much as possible by using the regenerative braking force without using the non-regenerative braking force by the braking device. Become. As a result, it is possible to increase the energy use efficiency of the power supply system.

  In addition, the amount of charge of the first power storage device and the second power storage device by the regenerative power can be appropriately adjusted by reflecting the remaining capacity or the state of deterioration of the first power storage device and the second power storage device.

In the first aspect , the control device may include a regenerative amount index value indicating a magnitude of the regenerative electric power to be output from the electric load during braking of the electric load, and a remaining capacity of the second power storage device. At least one of the regenerative powers can be obtained, and in the first braking process, a ratio of a charge amount of the regenerative power to the first power storage device to a charge amount of the second power storage device is determined by the regenerative amount index value. It is preferable that the power transmission circuit unit is controlled so as to change in accordance with at least one of the remaining power and the remaining capacity of the second power storage device ( third invention).

  Note that the “regeneration amount index value” means an index value that increases with an increase in regenerative power. The “regenerative amount index value” may be the value of the regenerative power itself, or may be another parameter value. For example, a regenerative braking force generated when the electric load outputs regenerative electric power can be used as the “regeneration amount index value”.

According to the third aspect , the ratio between the charge amount of the first power storage device and the charge amount of the second power storage device in the regenerative power output from the electric load is determined by the magnitude of the regenerative power, or The second power storage device can be changed in an appropriate form reflecting the state of the remaining capacity.

In the first to third inventions, when the first power storage device is a power storage device having lower deterioration resistance to charging than the second power storage device, the second braking process includes generating the regenerative electric power by the second power storage device. It is preferable to include a process of controlling the power transmission circuit unit to charge only one power storage device, and a process of controlling the braking device to generate the non-regenerative braking force (a fourth invention).

  According to this, in the second braking process, generation of a regenerative braking force by charging the regenerative electric power to the first power storage device and generation of a non-regenerative braking force by the braking device are performed in parallel. Becomes possible. For this reason, even when the required braking force is relatively large, the required braking force of the electric load is realized while keeping the amount of charge (charging speed) per unit time of the first power storage device from increasing as much as possible. It is possible to do. Therefore, in the second braking process, it is possible to charge the first power storage device while minimizing the progress of deterioration of the first power storage device.

In the fourth invention, in the second braking process, the control device controls the power transmission circuit unit to charge the regenerative power only to the first power storage device. The charging speed is limited to a predetermined speed threshold or less, and the predetermined speed threshold is set to be less than or equal to the predetermined speed threshold. The first power storage device responds to an increase in the charging speed in a speed range greater than the speed threshold. It is preferable that the degree of progress of the deterioration is a threshold value set in advance so as to be higher than the degree of progress of the deterioration of the first power storage device with respect to an increase in the charging speed in a speed range smaller than the speed threshold value ( Fifth invention).

  Here, in general, the first power storage device having relatively low deterioration resistance to charging tends to rapidly deteriorate when its charging speed exceeds a certain value. Therefore, in the seventh invention, the speed threshold is set as described above, and the charging is performed by limiting the charging speed of the first power storage device to the speed threshold or less.

  According to this, in the second braking process, the charging speed of the first power storage device by the regenerative power is limited to a relatively small speed range equal to or lower than the speed threshold, so that the deterioration of the first power storage device progresses. It is possible to charge the first power storage device while suppressing it with higher reliability. As a result, the progress of deterioration of the first power storage device caused by charging the first power storage device with the regenerative power can be effectively suppressed.

In the fourth to fifth aspects, the control device can acquire a remaining capacity of the first power storage device, and in the second braking process, determines a share ratio of the regenerative braking force in the required braking force. It is preferable that the first power storage device is configured to be changed according to the remaining capacity ( sixth invention).

  According to this, in the second braking process, it is possible to charge the first power storage device with an amount of regenerative power adapted to the remaining capacity of the first power storage device.

In the sixth aspect , in the second braking process, when the remaining capacity of the first power storage device is larger than a predetermined remaining capacity threshold, the control device may determine whether the regenerative braking force of the required braking forces It is preferable that the braking device is controlled such that the non-regenerative braking force matches the required braking force with the burden ratio being zero (a seventh invention).

  According to this, in the second braking process, when the remaining capacity of the first power storage device is smaller than the remaining capacity threshold, the first power storage device can be charged with regenerative power, while the first power storage device can be charged. When the remaining capacity of the device is larger than the remaining capacity threshold, charging of the first power storage device with regenerative power is not performed. Therefore, charging of the first power storage device with the regenerative power can be performed only in a highly necessary situation. Therefore, the progress of the deterioration of the first power storage device can be suppressed as much as possible.

In the first to seventh inventions described above, for example, an electric motor may be used as the electric load ( eighth invention).

Further, in the eighth invention, the power transmission circuit unit converts the output voltage of at least one of the first power storage device and the second power storage device and outputs the converted voltage, and the first power storage device or It is preferable to include an inverter that converts DC power input from the second power storage device or the voltage converter into AC power and supplies power to the electric motor (a ninth invention).

  According to this, power transmission between the electric motor as the electric load, the first power storage device, and the second power storage device can be appropriately controlled.

Further, a transportation device of the present invention includes the power supply system of the first to ninth inventions (a tenth invention). According to this transportation device, it is possible to realize a transportation device having the effects described in relation to the first to ninth aspects.

Further, a control method of a power supply system according to the present invention includes a first power storage device and a second power storage device,
A braking device that is operable by receiving power supply from at least one of the first power storage device and the second power storage device, and that generates a braking force that is applied to an electric load capable of outputting regenerative power in a state where the power supply is not received. A control method of a power supply system comprising:
Detecting whether each of the first power storage device and the second power storage device has a failure,
When the electric load is braked when both the first power storage device and the second power storage device are in a failure-free state, one or both of the first power storage device and the second power storage device are charged with the regenerative power. Control processing for generating the required braking force of the electric load by at least one of the regenerative braking force generated by the regenerative braking force and the non-regenerative braking force that is the braking force generated by the braking device. Executing a first braking process including a process of charging at least a part of the electric power to the second power storage device;
When the electric load is braked when the first power storage device is in a failure-free state and the second power storage device is in a faulty state, the regenerative power is generated by charging the one power storage device. A control process for generating a required braking force of the electric load by at least one of a regenerative braking force and a non-regenerative braking force generated by the braking device, wherein the regenerative electric power is applied only to the first power storage device. you; and a step of performing a second braking process including a process of charging a.

  According to this, similarly to the first invention, even if one of the two power storage devices (the second power storage device) fails, the other power storage device (the first power storage device) transfers the electric load to the electric load. The period during which power can be supplied can be extended as much as possible.

FIG. 1 is a diagram illustrating an overall configuration of a power supply system according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a circuit configuration of an example of a voltage converter included in the power supply system according to the embodiment. FIG. 2 is a diagram illustrating a circuit configuration of an example of an inverter included in the power supply system of the embodiment. 4 is a flowchart illustrating control processing of a control device included in the power supply system of the embodiment. FIG. 5 is a diagram showing, in a map form, a relationship between a required driving force and a remaining capacity of a second power storage device in a normal combined control process in a first control mode executed in STEP 4 of FIG. 4. 5 is a flowchart showing a normal combination control process executed in STEP 4 of FIG. 5 is a flowchart showing a normal combination control process executed in STEP 4 of FIG. 5 is a flowchart showing a normal combination control process executed in STEP 4 of FIG. 9 is a flowchart showing the processing of STEP 19 of FIG. 7 or STEP 25 of FIG. 10 is a graph showing the relationship between the coefficient α used in the processing of FIG. 9 and the remaining capacity of the second power storage device. FIG. 5 is a diagram showing, in a map form, a relationship between a required driving force and a remaining capacity of a second power storage device in a normal combined control process in a second control mode executed in STEP 4 of FIG. 4. FIG. 5 is a diagram showing, in a map form, a relationship between a required driving force and a remaining capacity of a second power storage device in a normal combined control process in a third control mode executed in STEP 4 of FIG. 4. 5 is a flowchart showing a stop extension control process executed in STEP 6 of FIG. 5 is a graph showing an example of a form of a change with time of a set of remaining capacity of each of a first power storage device and a second power storage device. 6 is a graph illustrating an example of a form of a change with time in a remaining capacity of a first power storage device. 7 is a graph illustrating an example of a form of a change with time in the remaining capacity of a second power storage device. 7 is a graph illustrating an example of a change over time in the remaining capacity of the first power storage device and the second power storage device during the execution of the stop extension control process. 5 is a flowchart illustrating a control process of the control device when braking the electric motor. FIG. 19A, FIG. 19B, and FIG. 19C are diagrams illustrating modes of the braking process in the first braking mode, the second braking mode, and the third braking mode, respectively. 19 is a flowchart showing the processing in STEP54 of FIG. 18 in the first braking mode (first embodiment). 19 is a flowchart showing the processing in STEP54 of FIG. 18 in the second braking mode. 19 is a flowchart showing the processing in STEP54 of FIG. 18 in the third braking mode. 9 is a graph illustrating a charge rate characteristic of the first power storage device. FIG. 5 is a diagram illustrating an example of a change with time of each of a first power storage device and a second power storage device before and after a failure of a second power storage device. 19 is a flowchart showing the processing in STEP54 of FIG. 18 in a first braking mode (second embodiment). The figure which shows the form of the braking process in 1st braking mode (2nd Embodiment or 3rd Embodiment). 19 is a flowchart showing the processing of STEP 54 in FIG. 18 in the first braking mode (third embodiment).

[First Embodiment]
A first embodiment of the present invention will be described below with reference to FIGS . Note that the first embodiment is an embodiment in which a later-described braking process in a first braking mode is a process of a reference example related to the first braking process in the present invention. With reference to FIG. 1, a power supply system 1 of the present embodiment is a system that supplies electric power to an electric motor 100 as an example of an electric load.

  In one example of the present embodiment, the power supply system 1 is mounted on a transportation device that uses the electric motor 100 as a propulsion force source, for example, an electric vehicle (not shown). In this case, the electric motor 100 performs a regenerative operation that outputs regenerative electric power by kinetic energy of an electric vehicle (hereinafter, sometimes simply referred to as a vehicle), in addition to a power running operation that generates a driving force by receiving power supply. Is possible.

  The power supply system 1 includes a first power storage device 2 and a second power storage device 3 as power sources, an electric motor 100, a power transmission line 4 disposed between the first power storage device 2 and the second power storage device 3, A control device 5 having a function of controlling the operation of the power supply system 1 and a braking device 6 for generating a braking force applied to the electric motor 100 are provided. Note that the electric load of the power supply system 1 may further include an electric load of accessories and the like in addition to the electric motor 100.

  In the present embodiment, the first power storage device 2 and the second power storage device 3 are power storage devices having different characteristics, and both are chargeable power storage devices. Specifically, first power storage device 2 and second power storage device 3 have the following characteristics.

  The first power storage device 2 is a power storage device having a higher energy density than the second power storage device 3. The energy density is the amount of electrical energy that can be stored per unit weight or per unit volume. The first power storage device 2 can be configured by, for example, a lithium ion battery or the like.

  Further, second power storage device 3 is a power storage device having a higher output density than first power storage device 2. The output density is an amount of electricity (an amount of electric energy per unit time or an amount of electric charge per unit time) that can be output per unit weight or per unit volume. The second power storage device 3 can be configured by, for example, a lithium ion battery, a nickel hydride battery, a capacitor, and the like.

  The first power storage device 2 having a relatively high energy density can store more electric energy than the second power storage device 3. In addition, the second power storage device 3 having a relatively high output density has a smaller impedance than the first power storage device 2, and thus can output large power instantaneously.

  Furthermore, the first power storage device 2 is a power storage device that has lower degradation resistance to fluctuations in its input / output (discharge amount and / or charge amount) than the second power storage device 3. For this reason, if the first power storage device 2 is discharged or charged in such a manner that its input / output fluctuates frequently, the deterioration is more likely to occur than in the second power storage device 3. The first power storage device 2 performs steady discharging or charging in a mode in which the input / output does not easily change, rather than performing discharging or charging in a mode in which the input / output changes frequently, Deterioration progress is suppressed.

  On the other hand, the second power storage device 3 having a relatively high deterioration resistance to input / output fluctuations, compared to the first power storage device, discharges even when the input / output fluctuations occur frequently. Therefore, the deterioration hardly occurs.

  Regarding the characteristics of the first power storage device 2 and the second power storage device 3 with respect to charging, the first power storage device 2 is more resistant to deterioration than charging the second power storage device 3 (particularly, charging at a high rate). Is low (deterioration due to charging easily proceeds). On the other hand, the second power storage device 3 has higher degradation resistance to charging than the first power storage device 2 (deterioration due to charging is less likely to progress).

  Further, the second power storage device 3 discharges or charges the battery such that the remaining capacity is maintained at a medium value, rather than performing the discharging or charging in a state where the remaining capacity is biased toward the high capacity side or the low capacity side. Charging has the characteristic that the progress of deterioration is suppressed. More specifically, as the remaining capacity of the second power storage device 3 increases from a medium value to a higher capacity side or decreases to a lower capacity side, the deterioration of the second power storage device 3 is more likely to progress. Has characteristics.

  In the present embodiment, the brake device 6 is configured by a vehicle brake device (such as a disc brake). In this case, the braking device 6 indirectly applies a braking force to the electric motor 100 by applying a braking force to the drive wheels 101 that are driven to rotate by the electric motor 100 when the vehicle travels.

  The power transmission path 4 is configured by a conducting wire, a wiring pattern of a substrate, or the like. A power transmission circuit unit 11 for controlling power transmission between the first power storage device 2, the second power storage device 3, and the electric motor 100 is provided in the power transmission path 4.

  The power transmission line 4 performs power transmission between the first power storage device 2 and the power transmission circuit unit 11 and power transmission line 4 a that performs power transmission between the first power storage device 2 and the power transmission circuit unit 11. It includes a power transmission path 4b and a power transmission path 4c for transmitting power between the electric motor 100 and the power transmission circuit unit 11. The power transmission lines 4a and 4b are provided with contactors 12 and 13 as switch units for performing respective connection and disconnection.

  The power transmission circuit unit 11 is configured to control power transmission between the first power storage device 2, the second power storage device 3, and the electric motor 100 according to a control signal given from the control device 5. More specifically, the power transmission circuit unit 11 selectively switches between a power supply source and a power supply destination, and supplies a power supply amount (a power supply amount) from the power supply source to the power supply destination according to a given control signal. It is possible to control.

  Specifically, the power transmission circuit unit 11 includes a voltage converter 15 that can step up or down the voltage input from the first power storage device 2 and output the same, and boosts or reduces the voltage input from the second power storage device 3. It comprises a voltage converter 16 capable of stepping down and outputting, and an inverter 17 capable of converting DC power into AC power and outputting the AC power.

  In this case, the voltage converters 15 and 16 are connected in parallel to the input side of the inverter 17. A capacitor 18 for smoothing a DC voltage input to the inverter 17 (a DC voltage output from the voltage converter 15 or 16) is provided on the input side of the inverter 17 (the output side of the voltage converters 15 and 16). It is interposed.

  Note that the power transmission circuit unit 11 may be a circuit unit including the contactors 12 and 13.

  The voltage converters 15 and 16 are so-called DC / DC converters, and each may be a known one. FIG. 2 shows an example circuit configuration of the voltage converters 15 and 16. The voltage converter 15 or 16 having the illustrated circuit configuration is a voltage converter capable of boosting and outputting the output voltage of the first power storage device 2 or the second power storage device 3. The voltage converter 15 or 16 includes a pair of primary terminals 21 a and 21 b connected to the first power storage device 2 or the second power storage device 3, and a pair of secondary terminals 22 a and 22 b connected to the inverter 17. Between them, a capacitor 23, a coil 24, and two high-side and low-side switch portions 27a and 27b are connected as shown. Each of the switch sections 27a and 27b is configured by connecting a semiconductor switch element 25 such as a transistor and a diode 26 in parallel.

  The voltage converter 15 or 16 having such a configuration controls the on / off of the respective semiconductor switch elements 25 of the switch units 27a and 27b by a control signal (a so-called duty signal) having a predetermined duty ratio, thereby providing the primary side. A DC voltage obtained by boosting a DC voltage input to the terminals 21a and 21b at a required boost rate is output from the secondary terminals 22a and 22b, or a DC voltage input to the secondary terminals 22a and 22b. Can be output from the primary terminals 21a and 21b. Then, it is also possible to variably control the above-mentioned step-up rate or step-down rate.

  Further, the voltage converter 15 or 16 can cut off the current supply (power transmission) from the secondary side to the primary side by controlling the semiconductor switch elements 25, 25 of both the switch sections 27a, 27b to be off. It is.

  Supplementally, the voltage converters 15 and 16 may have a circuit configuration other than that shown in FIG. Further, one or both of the voltage converters 15 and 16 may be configured to be able to step down the voltage input from the first power storage device 2 or the second power storage device 3 and output the same. Further, one of the voltage converters 15 and 16 can be omitted. The necessity of the voltage converter 15 or 16 or the type of voltage conversion (step-up or step-down) of the voltage converter 15 or 16 depends on the voltage required for the operation of the electric load, and the first power storage device 2 and the second power storage. Selection can be made in various various combination patterns according to the respective output voltages of the device 3.

  For example, when the first power storage device 2 is a power storage device having a higher voltage than the second power storage device 3, when one of the voltage converters 15 and 16 is omitted, the first power storage device 2 is connected to the first power storage device 2. It is preferable to omit the converted voltage converter 15. As described above, omitting one of the voltage converters 15 and 16 can reduce the cost required for realizing the power supply system.

  The inverter 17 may have a known circuit configuration. For example, FIG. 3 shows a circuit configuration of an example of the inverter 17 when the electric motor 100 is a three-phase electric motor. The illustrated inverter 17 is configured by connecting U-phase, V-phase, and W-phase three-phase arms 32u, 32v, and 32w in parallel between a pair of power terminals 31a and 31b to which a DC voltage is applied. Things. The arms 32u, 32v, 32w of each phase are configured by connecting two high-side and low-side switch sections 35a, 35b in series. Each of the switch sections 35a and 35b is configured by connecting a semiconductor switch element 33 such as a transistor and a diode 34 in parallel. The middle point between the switch sections 35a and 35b of the arms 32u, 32v and 32w of each phase is an output section for three-phase AC power.

  The inverter 17 having such a configuration controls the on / off of the respective semiconductor switch elements 33 of the switch sections 35a and 35b of the arms 32u, 32v and 32w of each phase by a control signal generated by a PWM control method or the like, thereby providing a power supply. The DC power input to the terminals 31a and 31b can be converted into three-phase AC power, and the AC power can be output to the electric motor 100 (the electric motor 100 during power running operation).

  Further, during the regenerative operation of the electric motor 100 (at the time of power generation), the ON / OFF of the semiconductor switch elements 33 of the switch sections 35a, 35b of the arms 32u, 32v, 32w of each phase is controlled to have a predetermined duty ratio. By controlling with a signal (a so-called duty signal), it is also possible to convert three-phase AC power input from the electric motor 100 into DC power and output it from the power supply terminals 31a and 31b.

  Supplementally, the number of phases (the number of arms) of the inverter 17 is set in accordance with the number of phases of AC power necessary for operating the electric load. In addition, when the electric load is an electric load (for example, a DC motor) that operates by supplying DC power, the inverter 17 can be omitted.

  The power transmission circuit unit 11 configured as described above controls the voltage converters 15 and 16 and the inverter 17 (specifically, a control signal for turning on and off the semiconductor switch elements 25 and 33 (having a predetermined duty ratio). By applying the duty signal to each of the voltage converters 15 and 16 and the inverter 17), power transmission between the first power storage device 2, the second power storage device 3, and the electric motor 100 can be controlled.

  For example, during power running operation of the electric motor 100, power is supplied to the electric motor 100 from one or both of the first power storage device 2 and the second power storage device 3, and power is supplied from the first power storage device 2 to the second power storage device 3, The second power storage device 3 can be charged, or one or both of the first power storage device 2 and the second power storage device 3 can be charged with regenerative power during the regenerative operation of the electric motor 100.

  In the present embodiment, the first power storage device 2 is not charged by the second power storage device 3, but the power transmission circuit unit 11 can be controlled to perform the charging.

  The control device 5 is configured by an electronic circuit unit including a CPU, a RAM, a ROM, an interface circuit, and the like. The control device 5 may be configured by a plurality of electronic circuit units that can communicate with each other.

  The control device 5 controls the power transmission circuit unit 11 as a function realized by a hardware configuration to be mounted or a program (software configuration) to be mounted, so that the first power storage device 2 and the second power storage device 3 are controlled. A power transmission control unit 41 that controls power transmission between the power storage device and the electric motor 100; a remaining capacity detection unit 42 that detects the remaining capacity (so-called SOC) of each of the first power storage device 2 and the second power storage device 3; It includes a failure detection unit 43 that detects the presence or absence of a failure in each of the first power storage device 2 and the second power storage device 3, and a braking device control unit 44 that controls the braking device 6.

  The control device 5 includes, as information necessary for realizing the above functions, a required driving force, which is a required value of a driving force (driving torque) to be generated by the electric motor 100 during power running operation, or deceleration of the vehicle. A required driving / braking force, which is a required braking force that is a required value of a braking force to be applied to the electric motor 100 at times, and a control mode that defines a control mode of the power transmission circuit unit 11 during the power running operation of the electric motor 100; Various kinds of sensing data are input.

  When the electric vehicle equipped with the power supply system 1 of the present embodiment is running, the required driving / braking force is, for example, a vehicle (not shown) according to the detected values of the operation amount of the accelerator pedal and the operation amount of the brake pedal. Set by the controller.

  Note that the control device 5 may have a function of setting the required driving / braking force.

  The control mode is set, for example, by a driver of an electric vehicle operating a mode switching operation device (not shown). In the present embodiment, three types of control modes, first to third control modes, which will be described later, are selectively set for the control device 5. Note that the control mode may be automatically set according to the traveling state, traveling environment, and the like of the electric vehicle.

  For example, the following data is input to the control device 5 as the sensing data. That is, a current sensor 51 that detects a current flowing through the first power storage device 2, a voltage sensor 52 that detects an output voltage of the first power storage device 2, a temperature sensor 53 that detects the temperature of the first power storage device 2, and a second power storage device 3, a voltage sensor 55 for detecting the output voltage of the second power storage device 3, a temperature sensor 56 for detecting the temperature of the second power storage device 3, and an input side of the voltage converter 15 (the first side). A current sensor 57 and a voltage sensor 58 for detecting a current and a voltage of the power storage device 2 respectively, a current sensor 59 for detecting a current of an output side of the voltage converter 15 (the inverter 17 side), and an input side of the voltage converter 16 ( A current sensor 60 and a voltage sensor 61 for respectively detecting a current and a voltage of the second power storage device 3), a current sensor 62 for detecting a current of an output side (the inverter 17) side of the voltage converter 16; Each time, each of the detection data of the voltage sensor 63 for detecting the voltage at the input side of the inverter 17 (voltage of each of the output side of the voltage converter 15, 16) is input to the control unit 5.

  The remaining capacity detection unit 42 of the control device 5 determines the remaining capacity of the first power storage device 2 using the detection data of the current sensor 51, the voltage sensor 52, and the temperature sensor 53 of the first power storage device 2, for example. Detect (estimate) sequentially. The remaining capacity detection unit 42 sequentially detects (estimates) the remaining capacity of the second power storage device 3 using the detection data of the current sensor 54, the voltage sensor 55, and the temperature sensor 56 of the second power storage device 3, for example. ).

  Here, various methods for detecting the remaining capacity of the power storage device have been conventionally proposed. Then, as a method for detecting the remaining capacity of the first power storage device 2 and the second power storage device 3, a known method can be employed.

  In addition, the method of detecting the remaining capacity of each of the first power storage device 2 and the second power storage device 3 uses a method that does not use any of the detection data of the energized current, the output voltage, and the temperature, or uses other detection data. May be used. The detection processing of the remaining capacity of each of the first power storage device 2 and the second power storage device 3 may be performed by a detection device different from the control device 5.

  The failure detection unit 43 detects the presence or absence of a failure in the first power storage device 2 using the detection data of the current sensor 51, the voltage sensor 52, and the temperature sensor 53 according to the first power storage device 2, for example.

  Further, the failure detection unit 43 detects the presence or absence of a failure in the second power storage device 3 using, for example, the detection data of the current sensor 54, the voltage sensor 55, and the temperature sensor 56 according to the second power storage device 3.

  In this case, for example, when any of the detected values of the current sensor 51, the voltage sensor 52, and the temperature sensor 53 related to the first power storage device 2 deviates from a predetermined range in a normal state, It is detected that a failure of the first power storage device 2 has occurred. Similarly, the failure detection unit 43 determines, for example, when any one of the detection values of the current sensor 54, the voltage sensor 55, and the temperature sensor 56 of the second power storage device 3 deviates from a normal range. , The failure of the second power storage device 3 is detected.

  Note that the process of detecting the presence or absence of a failure in each of first power storage device 2 and second power storage device 3 may be performed by a detection device different from control device 5.

  In addition, even if the first power storage device 2 and the second power storage device 3 are normal, the current sensor 51 of the first power storage device 2 and the voltage The case where any one of the current sensor 54, the voltage sensor 55, and the temperature sensor 56 of the sensor 52, the temperature sensor 53, and the second power storage device 3 described above may fail may be included.

  In addition, the power transmission control unit 41 includes, for example, detection data of the current sensors 57, 59, 60, 62 and voltage sensors 58, 61, 63, a required driving / braking force of the electric motor 100, and a remaining capacity detection unit 42. The voltage converters 15 and 16 and the inverter 17 of the power transmission circuit unit 11 are controlled using the detected values of the remaining capacity of the first power storage device 2 and the second power storage device 3 according to the above.

  Further, in a situation where the electric motor 100 is braked (when the vehicle is decelerated), the power transmission control unit 41 performs braking in place of or in addition to the regenerative braking force generated by the regenerative operation of the electric motor 100. The target value Br_cmd of the braking force (non-regenerative braking force) to be applied to the electric motor 100 from the device 6 is appropriately set, and the target value Br_cmd (hereinafter, referred to as the target braking force Br_cmd) is instructed to the braking device control unit 44.

  Then, when the target braking force Br_cmd is given from the power transmission control unit 41, the braking device control unit 44 controls the braking device 6 according to the target braking force Br_cmd.

(Control processing of the power transmission control unit)
Next, a control process of the power transmission control unit 41 of the control device 5 will be described in detail below. In the present embodiment, the control process of the power transmission control unit 41 in a state where the first power storage device 2 is normal (a state where the failure of the first power storage device 2 is not detected) will be described, and the first power storage device will be described. The description of the control process in a state where the failure of No. 2 is detected is omitted.

  When both the first power storage device 2 and the second power storage device 3 are normal, the control device 5 controls the power transmission control unit 41 to perform the control processing shown in the flowchart of FIG. It is executed sequentially in the processing cycle. The control process shown in the flowchart of FIG. 4 is a control process at the time of the power running operation of the electric motor 100.

  In STEP 1, the power transmission control unit 41 acquires the currently set control mode. Further, in STEP2, the power transmission control unit 41 detects the remaining value SOC1 of the first power storage device 2 (hereinafter sometimes referred to as the first remaining capacity SOC1) and the remaining value SOC2 of the second power storage device 3 (hereinafter, referred to as SOC1). And a detection value of the second remaining capacity SOC2).

  Next, the power transmission control unit 41 satisfies the condition that the detected value of the first remaining capacity SOC1 is equal to or greater than a predetermined threshold B1_th1 and the detected value of the second remaining capacity SOC2 is equal to or greater than a predetermined lower limit B2_min. It is determined in STEP 3 whether or not this is the case.

  The threshold value B1_th1 relating to the first remaining capacity SOC1 is a threshold value that is predetermined as a limit value of the first remaining capacity SOC1 necessary for performing a normal combination control process described later. As the threshold value B1_th1, for example, the power supply amount required to generate a constant output to the electric motor 100 (for example, the power supply amount required to cause the vehicle to cruise at a predetermined vehicle speed) is determined by the first power storage device 2 only. Can use the limit remaining capacity value at which power can be supplied to the electric motor 100. The threshold value B1_th1 is slightly higher than a lower limit value B1_min (a value close to zero) which is a limit remaining capacity value at which power can be supplied from the first power storage device 2 to the outside so as not to cause deterioration of the first power storage device 2. Is set to a value.

  The lower limit value B2_min for the second remaining capacity SOC2 is a limit remaining capacity value (a value close to zero) at which power can be supplied to the outside from the second power storage device 3 so as not to cause deterioration of the second power storage device 3. is there.

  The situation in which the result of the determination in STEP 3 is positive is a situation in which the first remaining capacity SOC1 and the second remaining capacity SOC2 have values in a normal range (normal range). In this situation, the power transmission control unit 41 executes the normal combination control processing corresponding to the currently set control mode in STEP4. Although the details will be described later, the normal combination control process supplies power to the electric motor 100 from one or both of the first power storage device 2 and the second power storage device 3 in a mode corresponding to the control mode, and performs the first power storage process. This is a process of controlling the power transmission circuit unit 11 to appropriately charge the first power storage device 2 to the second power storage device 3 when power is supplied from the device 2 to the electric motor 100.

  By the execution of the normal combination control process, the second power storage device 3 is appropriately charged from the first power storage device 2, but the remaining capacity SOC1 of the first power storage device 2 decreases. For this reason, the first remaining capacity SOC1 eventually becomes smaller than the threshold value B1_th1, and the determination result in STEP3 becomes negative.

  When the determination result in STEP3 is negative, the power transmission control unit 41 then determines that the detected value of the first remaining capacity SOC1 is equal to or greater than the lower limit B1_min and the detected value of the second remaining capacity SOC2 is It is determined in STEP 5 whether or not the condition that is equal to or more than the lower limit value B2_min is satisfied.

  The situation in which the determination result in STEP 5 is affirmative is, in particular, a situation in which the remaining capacity of the first power storage device 2 is small, but the cooperation between the first power storage device 2 and the second power storage device 3 for a certain period of time. Thus, power can be supplied to the electric motor 100 so as to generate the required driving force.

  In this situation, the power transmission control unit 41 executes the stop extension control process in STEP6. Although the details will be described later, the stop extension control process is a process of controlling the power transmission circuit unit 11 to consume the remaining capacity of both the first power storage device 2 and the second power storage device 3 as much as possible.

  Further, the situation in which the determination result in STEP 5 is negative is a situation in which it is difficult to supply electric power from first power storage device 2 and second power storage device 3 to electric motor 100. In this situation, the power transmission control unit 41 executes a stop process in STEP7. In this stop processing, the power transmission control unit 41 interrupts the output (discharge to the load side) of the first power storage device 2 and the second power storage device 3 and holds the voltage converter 15 so as to maintain the cutoff state. , 16 or the contactors 12, 13 are controlled.

  In this stop processing, the control device 5 informs that the vehicle cannot be driven due to insufficient remaining capacity of the first power storage device 2 and the second power storage device 3, or activates the electric motor 100. A notification output (a visual output or an audible output) is generated for notifying the driver of the vehicle that the vehicle cannot be driven.

(Normal combined control processing)
Next, the normal combination control processing in STEP 4 will be described in detail. Here, the terms in the following description will be supplemented.

  In the following description, “output” or “input” or “power supply amount” or “charge amount” of each of first power storage device 2 and second power storage device 3 is, for example, a power value (electricity per unit time). Energy amount).

  The “power supply amount corresponding to the required driving force DT_dmd” of the electric motor 100 means that when the power supply amount is supplied to the electric motor 100, the driving force generated by the electric motor 100 matches the required driving force DT_dmd. Alternatively, it means the amount of power supply that almost coincides.

  The “supply amount corresponding to the required driving force DT_dmd” is the required driving force DT_dmd and the rotational speed of the electric motor 100 (specifically, the rotor of the electric motor 100 when the “supply amount” is an electric amount represented by an electric power value). Or the rotation speed of the output shaft). In this case, the value of the “electric power supply amount corresponding to the required driving force DT_dmd” can be obtained from a map or an arithmetic expression from the required driving force DT_dmd and the detected value of the rotation speed of the electric motor 100, for example.

  Further, an arbitrary “power supply amount corresponding to the threshold value” regarding the required driving force DT__dmd means a power supply amount corresponding to the required driving force DT_dmd when the required driving force DT_dmd is made to match the threshold value.

(First control mode)
Assuming the above, the case where the control mode is set to the first control mode as the basic control mode among the first to third control modes will be described with reference to FIGS.

  The first control mode is a control mode in which the power transmission circuit unit 11 is controlled so that progress of deterioration of the first power storage device 2 and the second power storage device 3 can be suppressed as much as possible.

  An outline of the normal combination control process in the first control mode will be described with reference to FIG. FIG. 5 is a diagram illustrating the relationship between the amount of power to be supplied to the electric motor 100 (the amount of power supply) to be supplied to the electric motor 100 according to the required driving force DT_dmd of the electric motor 100 in the first control mode. FIG. 7 is a diagram illustrating a relationship between an output burden form and a second remaining capacity SOC2 in a map form.

  The shaded area in FIG. 5 is an area where the whole or a part of the power supply to the electric motor 100 is borne by the first power storage device 2, and the stippled area is the whole or a part of the power supply to the second power storage apparatus 3. Represents an area to be processed.

  More specifically, a hatched area in contact with a line (horizontal axis) where the required driving force DT_dmd = 0 represents an area in which only the first power storage device 2 bears the entire power supply amount to the electric motor 100. The stippling area in contact with the horizontal axis represents an area in which only the second power storage device 3 bears the entire power supply amount to the electric motor 100.

  In addition, the stippling area above the hatched area or the hatched area above the stippling area represents an area where both the first power storage device 2 and the second power storage device bear the amount of power supplied to the electric motor 100. .

  In the normal combined control process in the first control mode, as shown in FIG. 5, the value of the second remaining capacity SOC2 includes a high remaining capacity region in which SOC2 ≧ B2_th1 (including the remaining capacity value (100%) in a fully charged state). ), A case where the battery belongs to a medium remaining capacity region where B2_th1> SOC2 ≧ B2_th2, and a case where it belongs to a low remaining capacity region where B2_th2> SOC2, the first value according to the required driving force DT_dmd of the electric motor 100. The form of burden of each output of the power storage device 2 and the second power storage device 3 is roughly classified. The power supply amount corresponding to the required driving force DT_dmd of the electric motor 100 in one or both of the first power storage device 2 and the second power storage device 3 in a load form corresponding to each of the remaining capacity areas of high, medium, and low. To the electric motor 100.

  In the present embodiment, since the normal combination control process is a process performed when the detected value of the second remaining capacity SOC2 is equal to or more than the lower limit value B2_min, the low remaining capacity region is described in more detail as B2_th2 > SOC2 ≧ B2_min.

  Here, in FIG. 5, the thresholds B2_th1 and B2_th2 for dividing the second remaining capacity SOC2 are predetermined thresholds (fixed values) for the first control mode. These thresholds B2_th1 and B2_th2 are the actual values of the second remaining capacity SOC2 in order that the medium remaining capacity area whose range is defined by the thresholds B2_th1 and B2_th2 minimizes the progress of deterioration of the second power storage device 3. Is set in advance based on an experiment or the like so that the remaining capacity region preferably belongs to. Accordingly, in the middle remaining capacity region, the range of which is defined by the thresholds B2_th1 and B2_th2, charging and discharging of the second power storage device 3 is performed such that the actual value of the second remaining capacity SOC2 is maintained in the middle remaining capacity region as much as possible. This is a remaining capacity region in which the progress of the deterioration of the second power storage device 3 can be suitably suppressed when performed.

  Hereinafter, the normal combination control process in the first control mode will be specifically described.

  In the normal combination control processing, the power transmission control unit 41 sequentially executes the processing shown in the flowcharts of FIGS. 6 to 8 at a predetermined control processing cycle.

  In STEP 11, the power transmission control unit 41 acquires the required driving force DT_dmd of the electric motor 100. Then, the power transmission control unit 41 determines in STEP 12 whether or not the detected value of the second remaining capacity SOC2 acquired in STEP 2 is equal to or greater than the threshold B2_th1, which is the lower limit of the high remaining capacity area.

  The situation in which the determination result in STEP 12 is affirmative is a situation in which the detected value of SOC2 belongs to the high remaining capacity region. In this case, the power transmission control unit 41 next determines in STEP13 whether the required driving force DT_dmd is larger than a predetermined threshold value DT_th1.

  The threshold value DT_th1 is a predetermined fixed value (fixed value) in an example of the present embodiment. As the threshold value DT_th1, for example, in a state where the second remaining capacity SOC2 belongs to the high remaining capacity region, the upper limit driving force value that can be generated by the electric motor 100 by power supply only from the second power storage device 3, or a driving force value close thereto. Values can be adopted. In order to more appropriately suppress the deterioration of the second power storage device 3, the threshold value DT_th1 may be variably set based on a detected value of the temperature of the second power storage device 3 by the temperature sensor 56, or the like.

  The situation in which the determination result in STEP 13 is affirmative is the situation in the hatched area in the high remaining capacity area in FIG. In this case, in STEP 14, the power transmission control unit 41 determines that the output P2 of the second power storage device 3 matches the power supply amount corresponding to the threshold DT_th1, and that the output P1 of the first power storage device 2 The power transmission circuit unit 11 is controlled so as to match the shortage of the power supply amount obtained by subtracting the output P2 of the second power storage device 3 from the power supply amount corresponding to the force DT_dmd.

  The output P1 of the first power storage device 2 is, specifically, an amount of electricity (discharge amount) output from the first power storage device 2, and the output P2 of the second power storage device 3 is, specifically, a second power storage device. This is the amount of electricity (discharge amount) output from No. 3.

  Thus, the sum of the outputs P1 and P2 of the first power storage device 2 and the second power storage device 3 matches the power supply amount corresponding to the required driving force DT_dmd, so that the first power storage device 2 and the second power storage device A power supply amount corresponding to the required driving force DT_dmd is supplied to the electric motor 100 from both the devices 3. At this time, the share (output P2) of the second power storage device 3 in the power supply amount corresponding to the required driving force DT_dmd is set to the power supply amount corresponding to the threshold value DT_th1.

  Specifically, the processing in STEP 14 can be executed, for example, as follows. That is, the target value of the input voltage of the inverter 17 (= the output voltage of the voltage converters 15 and 16) is set according to the detected value of the rotation speed of the electric motor 100 and the like. Further, the power supply amount corresponding to the threshold value DT_th1 is set as a target value of the output power of the voltage converter 16, and the power supply amount corresponding to the required driving force DT_dmd is used to determine the output P2 ( The power supply amount obtained by subtracting the power supply amount corresponding to the threshold value DT_th1) is set as the target value of the output power of the voltage converter 15.

  Then, voltage converters 15 and 16 are controlled by a control signal (duty signal) so as to realize the target value of the input voltage of inverter 17 and the target value of the output power of each of voltage converters 15 and 16. At the same time, the inverter 17 sets a target power set according to the required driving force DT_dmd, or a target power obtained by limiting the target power by limit processing (limit processing for limiting the outputs of the power storage devices 2 and 3). Is feedback-controlled through a control signal (duty signal) so that a target current that can realize the above is supplied to the electric motor 100.

  On the other hand, the situation where the result of determination in STEP 13 is negative is the situation of the stippling area in the high remaining capacity area in FIG. In this case, the power transmission control unit 41 controls the power transmission circuit unit 11 in STEP 15 so that the output P2 of the second power storage device 3 matches the power supply amount corresponding to the required driving force DT_dmd.

  Thus, the electric power supply amount corresponding to the required driving force DT_dmd is supplied to the electric motor 100 only from the second power storage device 3 without using the first power storage device 2.

  The processing in STEP 15 can be specifically executed as follows, for example. That is, the target value of the input voltage of the inverter 17 (= the output voltage of the voltage converter 16) is set according to the detected value of the rotation speed of the electric motor 100 and the like. Further, the power supply amount corresponding to the required driving force DT_dmd is set as a target value of the output power of the voltage converter 16.

  Then, the voltage converter 16 is controlled so as to realize the target value of the input voltage of the inverter 17 and the target value of the output power of the voltage converter 16. At the same time, the inverter 17 is feedback-controlled so that the target current corresponding to the required driving force DT_dmd is supplied to the electric motor 100.

  Further, the voltage converter 15 is controlled to be in a power cutoff state. Alternatively, contactor 12 of first power storage device 2 is controlled to be in the off state.

  As described above, when the detected value of the second remaining capacity SOC2 belongs to the high remaining capacity region, at least the second power storage device 2 and the second power storage device 3 during the power running operation of the electric motor 100. Power is supplied from the power storage device including the power storage device 3 to the electric motor 100. Therefore, the second power storage device 3 can be positively discharged, and the remaining capacity SOC2 of the second power storage device 3 can be made to approach the middle remaining capacity region. Therefore, it is possible to suppress the deterioration of the second power storage device 3 while satisfying the required driving force DT_dmd of the electric motor 100.

  Supplementally, the threshold value DT_th1 used in the determination process in STEP 13 can be set in a different manner from the above. For example, the threshold value is set so that the power supply amount corresponding to the threshold value DT_th1 becomes a predetermined constant value (for example, the upper limit power supply amount that the second power storage device 3 can output in the high remaining capacity area or a constant power supply amount close thereto). DT_th1 may be set. Further, the threshold value DT_th1 may be set to be changed according to the detected value of the second remaining capacity SOC2.

  If the determination result in STEP 12 is negative, the power transmission control unit 41 further determines in STEP 16 that the detected value of the second remaining capacity SOC2 is equal to or greater than the threshold B2_th2, which is the lower limit of the middle remaining capacity area. Is determined.

  The situation in which the determination result in STEP 16 is affirmative is a situation in which the detected value of SOC2 belongs to the middle remaining capacity area. In this situation, the power transmission control unit 41 next determines in STEP 17 (see FIG. 7) whether the required driving force DT_dmd is greater than a predetermined threshold value DT_th2.

  In this case, the predetermined threshold value DT_th2 is a threshold value variably set according to the detected value of the second remaining capacity SOC2, as shown in FIG. 5, for example, in the example of the present embodiment. Specifically, the threshold value DT_th2 is set to increase as the detected value of SOC2 decreases. Further, the threshold value DT_th2 is set to a driving force value larger than a driving force that can be generated by the electric motor 100 when a basic power supply amount P1_base described later is supplied to the electric motor 100.

  The situation in which the determination result in STEP 17 is affirmative is the situation in the shaded area above the stippling area in the middle remaining capacity area in FIG. In this case, in step 18, the power transmission control unit 41 determines that the output P2 of the second power storage device 3 matches the power supply amount of the predetermined value, and that the output P1 of the first power storage device 2 has the required driving force DT_dmd The power transmission circuit unit 11 is controlled so as to match the shortage of the power supply amount obtained by subtracting the output P2 corresponding to the burden on the second power storage device 3 from the power supply amount corresponding to the power supply amount.

  In this case, specific control of the power transmission circuit unit 11 can be performed in the same manner as in STEP 14 of FIG.

  Thus, the sum of the outputs P1 and P2 of the first power storage device 2 and the second power storage device 3 matches the power supply amount corresponding to the required driving force DT_dmd, so that the first power storage device 2 and the second power storage device A power supply amount corresponding to the required driving force DT_dmd is supplied to the electric motor 100 from both the devices 3. Further, at this time, the portion of the power supply amount corresponding to the required driving force DT_dmd that is borne by the second power storage device 3 is set to a predetermined value.

  In this case, as the predetermined amount of power supply output from the second power storage device 3, for example, an upper limit power supply amount that the second power storage device 3 can output in the middle remaining capacity region or a constant value power supply amount close to the upper limit power supply amount is used. obtain. Further, as the power supply amount of the predetermined value, for example, a power supply amount set so as to change according to the detected value of the second remaining capacity SOC2 can be used.

  On the other hand, if the determination result in STEP 17 is negative, then in STEP 19, the power transmission control unit 41 determines the basic power supply amount P1_base, which is the basic value of the output P1 of the first power storage device 2, in the second remaining capacity SOC2. Is determined in accordance with the detected value of.

  Here, the basic power supply amount P1_base is a lower limit that is output from the first power storage device 2 regardless of the required driving force DT_dmd in a state where the detected value of the second remaining capacity SOC2 belongs to the middle remaining capacity region or the low remaining capacity region. Is the quantity of electricity. That is, in the present embodiment, when the detected value of the second remaining capacity SOC2 belongs to the middle remaining capacity area or the low remaining capacity area, the basic power supply amount P1_base, Alternatively, the power transmission circuit unit 11 is controlled such that a larger amount of power is output.

  The basic power supply amount P1_base is set, for example, as shown in the flowchart of FIG. That is, in STEP 31, the power transmission control unit 41 determines a coefficient α that defines a pattern of a change in the basic power supply amount P1_base according to the detected value of the second remaining capacity SOC2 according to the detected value of the SOC2.

  In this case, the coefficient α is set, for example, in a pattern shown in the graph of FIG. In this example, the value of the coefficient α is a value within a range from “0” to “1”. The value of the coefficient α is basically such that the detected value of the SOC2 is small in the remaining capacity region (lower remaining capacity region) obtained by combining the middle remaining capacity region and the low remaining capacity region of the second power storage device 3. Is set to be larger.

  More specifically, when the detected value of SOC2 belongs to the medium remaining capacity area, the value of the coefficient α decreases as the detected value of SOC2 decreases from the upper threshold B2_th1 of the middle remaining capacity area to the lower threshold B2_th2, It is set so as to continuously increase from “0” to “1”.

  Further, when the detected value of the second remaining capacity SOC2 belongs to the low remaining capacity area, the value of α is set to the maximum value “1”.

  Next, in STEP 32, the power transmission control unit 41 multiplies the value of the coefficient α determined as described above by a power supply amount P1b of a predetermined value (fixed value), thereby obtaining a basic power supply amount P1_base (= α × P1b). Is calculated. The power supply amount P1b is the maximum value of the basic power supply amount P1_base.

  Thus, the basic power supply amount P1_base is determined so as to change in the same pattern as the coefficient α according to the detected value of the second remaining capacity SOC2.

  Note that, for example, an upper limit value of the output P1 of the first power storage device 2 is set in accordance with a detected value of the first remaining capacity SOC1, and when the basic power supply amount P1_base calculated as described above exceeds the upper limit value. Alternatively, the basic power supply amount P1_base may be determined by executing a limit process for forcibly restricting the basic power supply amount P1_base to the upper limit subsequent to the process of STEP32.

  Further, for example, instead of the processing of STEPS 31 and 32, the basic power supply amount P1_base may be directly determined from the detected value of the second remaining capacity SOC2 using a map or an arithmetic expression created in advance.

  Returning to FIG. 7, after executing the processing of STEP 19 as described above, the power transmission control unit 41 next determines in STEP 20 whether or not the power supply amount corresponding to the required driving force DT_dmd is equal to or less than the basic power supply amount P1_base. Judge. The determination process in STEP 20 is equivalent to a process of determining whether the required driving force DT_dmd is equal to or less than a threshold value obtained by converting the basic power supply amount P1_base into a driving force value according to a detected value of the rotation speed of the electric motor 100. It is. The threshold in this case is a threshold DT_th4 indicated by a broken line in FIG. The threshold value DT_th4 indicated by a broken line in FIG. 5 is a threshold value when the rotation speed of the electric motor 100 is constant.

  The situation in which the determination result in STEP 20 is affirmative is the situation in the hatched area at the bottom of the middle remaining capacity area in FIG. In this situation, in STEP 21, the power transmission control unit 41 determines that the output P1 of the first power storage device 2 matches the basic power supply amount P1_base, and that the input of the second power storage device 3, that is, the charge amount is the required drive amount from the basic power supply amount P1_base. The power transmission circuit unit 11 is controlled so as to match a surplus power supply amount obtained by subtracting the power supply amount corresponding to the force DT_dmd (excess power supply amount).

  Thereby, the basic power supply amount P1_base set as described above according to the detected value of the second remaining capacity SOC2 is output from the first power storage device 2 without depending on the required driving force DT_dmd, and the basic power supply amount P1_base The power supply amount corresponding to the required driving force DT_dmd is supplied from the first power storage device 2 to the electric motor 100, and the surplus power supply amount obtained by subtracting the power supply amount corresponding to the required driving force DT_dmd from the basic power supply amount P1_base is the first power storage device. 2 to the second power storage device 3.

  The processing in STEP 21 can be specifically executed as follows, for example. That is, the target value of the input voltage of the inverter 17 (= the output voltage of the voltage converter 15) is set according to the detected value of the rotation speed of the electric motor 100 and the like. Further, the basic power supply amount P1_base is set as a target value of the output power of the voltage converter 15, and the power supply amount obtained by subtracting the power supply amount corresponding to the required driving force DT_dmd from the basic power supply amount P1_base is input to the input side of the voltage converter 16. It is set as a target value of the power supplied from the second power storage device 3 to the second power storage device 3.

  The voltage converter 15 is controlled so as to realize the target value of the input voltage of the inverter 17 and the target value of the output power of the voltage converter 15, and the power supplied from the voltage converter 16 to the second power storage device 3. The voltage converter 16 is controlled so as to realize the target value. At the same time, the inverter 17 is feedback-controlled so that the target current corresponding to the required driving force DT_dmd is supplied to the electric motor 100.

  When the basic power supply amount P1_base matches the power supply amount corresponding to the required driving force DT_dmd, the input (charge amount) of the second power storage device 3 becomes zero, so that the voltage converter 16 is controlled to be in the power cutoff state. Alternatively, the contactor 13 on the second power storage device 3 side is controlled to the off state.

  On the other hand, the situation where the determination result of STEP 20 is negative is the situation of the stippling area in the middle remaining capacity area in FIG. In this case, in STEP 22, the power transmission control unit 41 determines that the output P1 of the first power storage device 2 matches the basic power supply amount P1_base, and that the output P2 of the second power storage device corresponds to the required driving force DT_dmd. The power transmission circuit unit 11 is controlled so as to match the shortage power supply amount obtained by subtracting the basic power supply amount P1_base from the power supply amount.

  In this case, specific control of the power transmission circuit unit 11 can be performed in the same manner as in STEP 14 of FIG.

  Thus, the sum of the outputs P1 and P2 of the first power storage device 2 and the second power storage device 3 matches the power supply amount corresponding to the required driving force DT_dmd, so that the first power storage device 2 and the second power storage device A power supply amount corresponding to the required driving force DT_dmd is supplied to the electric motor 100 from both the devices 3. At this time, the share (output P1) of the first power storage device 2 in the power supply amount corresponding to the required driving force DT_dmd is the basic power supply amount set as described above according to the detected value of the second remaining capacity SOC2. P1_base is set.

  Supplementally, in STEP 22 described above, the output P2 of the second power storage device 3 (the insufficient power supply amount obtained by subtracting the basic power supply amount P1_base from the power supply amount corresponding to the required driving force DT_dmd) is used as the second power storage device 3 in the medium remaining capacity region. Is larger than the upper limit power supply amount that can be output, the output P2 of the second power storage device 3 is limited to the upper limit power supply amount, and the power transmission circuit unit 11 is controlled by the same processing as in STEP18. You may.

  Alternatively, the threshold value DT_th2 in the determination process in STEP 17 is a value obtained by adding the fixed amount of the power supply amount at or near the upper limit of the second power storage device 3 to the basic power supply amount P1_base to the power supply amount corresponding to the threshold value DT_th2. May be set to match.

  As described above, when the detected value of the second remaining capacity SOC2 belongs to the middle remaining capacity region, at least the first power storage device 2 and the second power storage device 3 of the first power storage device 2 and the second power storage device 3 during the power running operation of the electric motor 100. Power is supplied from the power storage device including the power storage device 2 to the electric motor 100.

  When the required driving force DT_dmd is equal to or less than the threshold value DT_th2, the output P1 of the first power storage device 2 is held at the basic power supply amount P1_base set according to the detected value of the second remaining capacity SOC2. When the basic power supply amount P1_base is larger than the power supply amount corresponding to the required driving force DT_dmd (in other words, the required driving force DT_dmd is larger than the threshold DT_th4 obtained by converting the basic power supply amount P1_base into the driving force value of the electric motor 100). Is smaller), the power supply amount corresponding to the required driving force DT_dmd of the basic power supply amount P1_base is supplied to the electric motor 100 only from the first power storage device 2, and the surplus power supply amount is supplied to the second power storage device. 3 is charged.

  Further, when the required driving force DT_dmd is equal to or less than the threshold value DT_th2, the basic power supply amount P1_base is smaller than the power supply amount corresponding to the required driving force DT_dmd (in other words, the required driving force DT_dmd is larger than the threshold value DT_th4). In the case), the basic power supply amount P1_base is supplied from the first power storage device 2 to the electric motor 100, and the insufficient power supply amount is supplied from the second power storage device 3 to the electric motor 100.

  Therefore, when the detected value of the second remaining capacity SOC2 belongs to the middle remaining capacity area, a situation occurs in which power is supplied from the second power storage device 3 to the electric motor 100 as compared to the case where the detected value belongs to the high remaining capacity area. It becomes difficult. Further, as the second remaining capacity SOC2 decreases, the range of the required driving force DT_dmd in which the charging from the first power storage device 2 to the second power storage device 3 is performed is expanded, and the second power storage device is also charged. 3 easily increases the charge amount.

  As a result, the second remaining capacity SOC2 can be kept in the middle remaining capacity area as much as possible. As a result, the progress of the deterioration of the second power storage device 3 can be suppressed as much as possible.

  When the required driving force DT_dmd is equal to or less than the threshold value DT_th2, the basic power supply amount P1_base output from the first power storage device 2 is set according to the second remaining capacity SOC2 without depending on the required driving force DT_dmd. . For this reason, the output P2 or the input of the second power storage device 3 fluctuates following the fluctuation of the required driving force DT_dmd, while the fluctuation of the output P1 of the first power storage device 2 changes with respect to the fluctuation of the required driving force DT_dmd. The sensitivity is low.

  As a result, the output P1 of the first power storage device 2 is less likely to fluctuate frequently and has high stability. As a result, the progress of the deterioration of the first power storage device 2 can be suppressed as much as possible.

  Next, a situation in which the result of the determination in STEP 16 is negative is a situation in which the detected value of the second remaining capacity SOC2 belongs to the low remaining capacity area. In this situation, the power transmission control unit 41 next determines whether or not the required driving force DT_dmd is larger than a predetermined threshold DT_th3 in STEP23 (see FIG. 8).

  In this case, the predetermined threshold value DT_th3 is set to a predetermined constant value in one example of the present embodiment. Further, the threshold value DT_th3 is set to a driving force value larger than a driving force that the electric motor 100 can generate when the basic power supply amount P1_base set as described above according to the second remaining capacity SOC2 is supplied to the electric motor 100. Is done.

  The threshold value DT_th3 may be set so that the power supply amount corresponding to the threshold value DT_th3 is the upper limit power supply amount (> P1_base) of the first power storage device 2 or a constant power supply amount close thereto.

  The situation in which the determination result in STEP 23 is affirmative is the situation of the stippling area in the low remaining capacity area in FIG. In this case, in STEP 24, the power transmission control unit 41 determines that the output P1 of the first power storage device 2 matches the power supply amount of the predetermined value, and that the output P2 of the second power storage device 3 is the required driving force DT_dmd The power transmission circuit unit 11 is controlled so as to match the shortage of the power supply amount obtained by subtracting the output P1 corresponding to the load of the first power storage device 2 from the power supply amount corresponding to the power supply amount.

  In this case, specific control of the power transmission circuit unit 11 can be performed in the same manner as in STEP 14 of FIG.

  Thus, the sum of the outputs P1 and P2 of the first power storage device 2 and the second power storage device 3 matches the power supply amount corresponding to the required driving force DT_dmd, so that the first power storage device 2 and the second power storage device A power supply amount corresponding to the required driving force DT_dmd is supplied to the electric motor 100 from both the devices 3. Further, at this time, the portion of the power supply amount corresponding to the required driving force DT_dmd that is borne by the first power storage device 2 is set to a predetermined value.

  In this case, as the predetermined amount of power supply output from first power storage device 2, for example, an upper limit power supply amount that can be output by first power storage device 2 or a constant value power supply amount close to the upper limit power supply amount may be used. Further, as the power supply amount of the predetermined value, it is also possible to use a power supply amount set so as to change according to one or both of the detection value of the first remaining capacity SOC1 and the detection value of the second remaining capacity SOC2. .

  On the other hand, if the determination result in STEP 23 is negative, the power transmission control unit 41 next determines in STEP 25 the basic power supply amount P1_base, which is the basic value of the output P1 of the first power storage device 2, to the second remaining capacity SOC2. Is determined in accordance with the detected value of.

  The processing in STEP25 is the same as the processing in STEP19. Here, in the present embodiment, since the coefficient α in the low remaining capacity region is the maximum value “1”, the basic power supply amount P1_base determined in STEP 25 is the maximum value P1b.

  As in the case of the processing in STEP 19, for example, the upper limit of the output P1 of the first power storage device 2 is set according to the detected value of the first remaining capacity SOC1, and the like, and the upper limit is set according to the second remaining capacity SOC2. When the determined basic power supply amount P1_base exceeds the upper limit value, the basic power supply amount P1_base may be forcibly limited to the upper limit value.

  Also, for example, instead of executing the process of the flowchart of FIG. 9 in STEP 25, the basic power supply amount P1_base is directly determined from the detected value of the second remaining capacity SOC2 using a map or an arithmetic expression created in advance. It may be.

  After executing the processing in STEP 25, the power transmission control unit 41 next determines in STEP 26 whether the power supply amount corresponding to the required driving force DT_dmd is equal to or less than the basic power supply amount P1_base. In the determination process of STEP 26, the required driving force DT_dmd is obtained by converting the basic power supply amount P1 into a driving force value in accordance with the detected value of the rotation speed of the electric motor 100, as in the determination process of STEP 20 described above. 5) It is equivalent to the process of determining whether or not:

  The situation in which the determination result in STEP 26 is affirmative is a situation in which the required driving force DT_dmd is equal to or less than the threshold DT_th4 in a hatched area in the low remaining capacity area in FIG. In this situation, in STEP 27, the power transmission control unit 41 determines that the output P1 of the first power storage device 2 matches the basic power supply amount P1_base, and that the input (charge amount) of the second power storage device 3 is changed from the basic power supply amount P1_base. The power transmission circuit unit 11 is controlled so as to match the surplus power supply amount obtained by subtracting the power supply amount corresponding to the required driving force DT_dmd.

  The specific control of the power transmission circuit unit 11 in this case can be performed in the same manner as in STEP 21 of FIG.

  Thereby, the basic power supply amount P1_base set as described above according to the detected value of the second remaining capacity SOC2 is output from the first power storage device 2 without depending on the required driving force DT_dmd, and the basic power supply amount P1_base The power supply amount corresponding to the required driving force DT_dmd is supplied from the first power storage device 2 to the electric motor 100, and the surplus power supply amount obtained by subtracting the power supply amount corresponding to the required driving force DT_dmd from the basic power supply amount P1_base is the first power storage amount. The second power storage device 3 is charged from the device 2.

  On the other hand, the situation where the determination result of STEP 26 is negative is a situation where the required driving force DT_dmd is larger than the threshold DT_th4 in the shaded area in the low remaining capacity area in FIG. In this case, the power transmission control unit 41 controls the power transmission circuit unit 11 so that the output P1 of the first power storage device 2 matches the power supply amount corresponding to the required driving force DT_dmd in STEP28.

  Thus, the electric power supply amount corresponding to the required driving force DT_dmd is supplied to the electric motor 100 only from the first power storage device 2 without using the second power storage device 3.

  The processing in STEP 28 can be specifically executed as follows, for example. That is, the target value of the input voltage of the inverter 17 (= the output voltage of the voltage converter 15) is set according to the detected value of the rotation speed of the electric motor 100 and the like. Further, the power supply amount corresponding to the required driving force DT_dmd is set as a target value of the output power of the voltage converter 15.

  Then, voltage converter 15 is controlled by a control signal (duty signal) so as to realize the target value of the input voltage of inverter 17 and the target value of the output power of voltage converter 15. At the same time, the inverter 17 sets a target power set according to the required driving force DT_dmd or a target power obtained by limiting the target power by limit processing (limit processing for limiting the output of the first power storage device 2). Feedback control is performed through a control signal (duty signal) so that a achievable target current is supplied to the electric motor 100.

  Further, the voltage converter 16 is controlled to be in a power cutoff state. Alternatively, the contactor 13 on the second power storage device 3 side is controlled to be in the off state.

  As described above, when the detected value of the second remaining capacity SOC2 belongs to the low remaining capacity region, at least the first power storage device 2 and the second power storage device 3 of the first power storage device 2 and the second power storage device 3 during the power running operation of the electric motor 100. Power is supplied from the power storage device including the power storage device 2 to the electric motor 100.

  When the power supply amount corresponding to the required driving force DT_dmd is equal to or less than the basic power supply amount P1_base, the output P1 of the first power storage device 2 is held at the basic power supply amount P1_base irrespective of the required driving force DT_dmd. Then, the power supply amount corresponding to the required driving force DT_dmd of the basic power supply amount P1_base is supplied to the electric motor 100 only from the first power storage device 2, and the surplus power supply amount is used for charging the second power storage device 3. Is done. For this reason, the input of the second power storage device 3 fluctuates following the fluctuation of the required driving force DT_dmd, while the fluctuation of the output P1 (= P1_base) of the first power storage device 2 changes with respect to the fluctuation of the required driving force DT_dmd. And low sensitivity.

  When the power supply amount corresponding to the required driving force DT_dmd is larger than the basic power supply amount P1_base, the required driving force DT_dmd from only the first power storage device 2 to the electric motor 100 until the required driving force DT_dmd exceeds the threshold value DT_th3. Is supplied, and only when the required driving force DT_dmd exceeds the threshold value DT_th3, the second power storage device 3 bears a part of the power supply amount corresponding to the required driving force DT_dmd.

  Therefore, when the detected value of the second remaining capacity SOC2 belongs to the low remaining capacity area, power is supplied from the second power storage device 3 to the electric motor 100 as compared with the case where the detected value belongs to the high remaining capacity area or the middle remaining capacity area. Is less likely to occur.

  Furthermore, since the basic power supply amount P1_base in the low remaining capacity region is the maximum value P1b, the range and the charge amount of the required driving force DT_dmd in which the charging from the first power storage device 2 to the second power storage device 3 is performed. It is larger than the medium remaining capacity area.

  As a result, as long as the state where the required driving force DT_dmd becomes larger than the threshold value DT_th3 does not continue, the second remaining capacity SOC2 easily returns to the middle remaining capacity area from the low remaining capacity area.

  Further, when the power supply amount corresponding to the required driving force DT_dmd is equal to or less than the basic power supply amount P1_base, the basic power supply amount P1_base output from the first power storage device 2 becomes the second remaining capacity SOC2 regardless of the required driving force DT_dmd. It is set according to. In particular, the basic power supply amount P1_base in the low remaining capacity region is a constant value (= P1b). Therefore, the output P1 of the first power storage device 2 does not fluctuate according to the fluctuation of the required driving force DT_dmd.

  Further, in a situation where the required driving force DT_dmd is larger than the threshold value DT_th3, the output P1 of the first power storage device 2 is set to a predetermined constant value, so that the output P1 of the first power storage device 2 is changed according to the required driving force DT_dmd. It does not fluctuate.

  As a result, the output P1 of the first power storage device 2 in the low remaining capacity region does not easily change frequently, and has high stability. As a result, the progress of the deterioration of the first power storage device 2 can be suppressed as much as possible.

  The above is the details of the normal combined control process in the case where the control mode is set to the first control mode as the basic control mode among the first to third control modes.

(Second control mode)
Next, the normal combination control processing when the control mode is set to the second control mode will be described.

  FIG. 11 is a diagram showing the relationship between the amount of electricity to be supplied to the electric motor 100 (the amount of electric power supply) and the amount of electric power to be supplied to the electric motor 100 in the second control mode, according to the required driving force DT_dmd. FIG. 7 is a diagram illustrating a relationship between an output burden form and a second remaining capacity SOC2 in a map form. The meanings of the hatched area and the stippling area in FIG. 11 are the same as those in FIG. Further, a two-dot chain line in FIG. 11 indicates a line of the threshold value DT_th4 indicated by a broken line in FIG. 5 for comparison with the first control mode.

  As can be seen by comparing FIG. 5 relating to the first control mode with FIG. 11 relating to the second control mode, the second control mode is responsible for the output burden of each of the first power storage device 2 and the second power storage device 3. This is a control mode in which the threshold for classifying the form is different from the first control mode.

  In the second control mode in the present embodiment, when the second remaining capacity SOC2 is relatively low, the second power storage device 3 is more easily charged than in the first control mode, and the second remaining capacity SOC2 is compared. In the extremely high state, the range of the required driving force DT_dmd for supplying electric power from the second power storage device 3 to the electric motor 100 is expanded as compared with the first control mode.

  More specifically, in the second control mode in the present embodiment, the upper limit threshold B2_th1 of the middle remaining capacity region of the second remaining capacity SOC2 is set to a value higher than that of the first control mode in advance.

  Further, the basic power supply amount P1_base of the first power storage device 2 in the low remaining capacity region and the medium remaining capacity region of the second power storage device 3 is set to be larger than in the first control mode (in other words, the basic power supply amount P1_base is The threshold value DT_th4 (converted value when the rotation speed is fixed), which is converted into a driving force value according to the rotation speed of the motor 100, is larger than that in the first control mode), and the second remaining capacity SOC2 is Determined according to the detected value.

  Such a basic power supply amount P1_base can be determined in the same manner as in the first control mode. For example, similarly to the case of the first control mode, the basic power supply amount P1_base (= α × P1b) can be determined by the same processing as the processing shown in the flowchart of FIG. However, in this case, the maximum value P1b of the basic power supply amount P1_base is set in advance to a value larger than that in the first control mode. As the maximum value P1b of the basic power supply amount P1_base in the second control mode, for example, an upper limit power supply amount that can be output from the first power storage device 2 or a power supply amount close thereto can be used.

  Note that the basic power supply amount P1_base in the second control mode can be directly determined from, for example, a detected value of the second remaining capacity SOC2 using a map or an arithmetic expression created in advance.

  In the second control mode, the threshold value DT_th1 of the required driving force DT_dmd in the high remaining capacity region and the threshold value DT_th2 of the required driving force DT_dmd in the middle remaining capacity region are both set to be larger than those in the first control mode. Is set to

  Further, in the example shown in FIG. 11, the threshold value DT_th3 of the required driving force DT_dmd in the low remaining capacity region is set so that the corresponding power supply amount matches the basic power supply amount P1_base. However, the power supply amount corresponding to the threshold DT_th3 may be larger than the basic power supply amount P1_base as long as it is equal to or less than the upper limit power supply amount that can be output from the first power storage device 2.

  The manner of setting the threshold values for the second remaining capacity SOC2 and the required driving force DT_dmd in the second control mode is the same as that in the first control mode except for the items described above.

  The normal combination control process in the second control mode is executed according to the flowcharts of FIGS. 6 to 8 as in the first control mode. When the threshold value DT_th3 of the required driving force DT_dmd in the low remaining capacity region is set so that the corresponding power supply amount matches the basic power supply amount P1_base, the processing in STEPS 26 and 28 in FIG. 8 can be omitted.

  The normal combination control process in the second control mode is executed as described above.

  In the second control mode, the remaining capacity area (lower remaining capacity area) combining the low remaining capacity area and the middle remaining capacity area is wider than in the first control mode, and the first power storage device is provided in the remaining capacity area. The range of the required driving force DT_dmd from which the second power storage device 3 is charged to the second power storage device 3 is expanded from the first control mode. For this reason, the second remaining capacity SOC2 is easily maintained in a state close to the high remaining capacity area.

  Further, in the middle remaining capacity region and the high remaining capacity region, the range of the required driving force DT_dmd in which electric power is supplied from the second power storage device 3 to the electric motor 100 is also wider than in the first control mode.

  As a result, in a state where the required driving force DT_dmd is relatively large (a state where DT_dmd> DT_th4), the electric motor 100 is responded to the fluctuation of the required driving force DT_dmd with high responsiveness in a wide range of the required driving force DT_dmd. Can be changed. Consequently, the responsiveness of the actual driving force of the electric motor 100 to the change in the required driving force DT_dmd can be improved.

  In the present embodiment, both the upper limit threshold value B2_th1 of the middle remaining capacity region of the second remaining capacity SOC2 and the basic power supply amount P1_base of the first power storage device 2 are set to values larger than those in the first control mode. , The threshold value B2_th1 or the basic power supply amount P1_base may be set to a value larger than that in the first control mode. Even in this case, the area in which charging from first power storage device 2 to second power storage device 3 is performed can be expanded more than in the first control mode.

(3rd control mode)
Next, the normal combination control processing when the control mode is set to the third control mode will be described.

  FIG. 12 is a diagram illustrating the relationship between the amount of electricity to be supplied to the electric motor 100 (the amount of power supply) and the amount of electric power to be supplied to the electric motor 100 in the third control mode, according to the required driving force DT_dmd. FIG. 7 is a diagram illustrating a relationship between an output burden form and a second remaining capacity SOC2 in a map form. The meanings of the hatched area and the stippling area in FIG. 12 are the same as those in FIG. Further, a two-dot chain line in FIG. 12 indicates a threshold DT_th4 line indicated by a broken line in FIG. 5 for comparison with the first control mode.

  As can be seen by comparing FIG. 5 relating to the first control mode with FIG. 12 relating to the third control mode, the third control mode is responsible for the output burden of each of the first power storage device 2 and the second power storage device 3. This is a control mode in which the threshold for classifying the form is different from the first control mode.

  In the third control mode in the present embodiment, the second power storage device 3 is less likely to be charged than in the first control mode even when the second remaining capacity SOC2 is relatively low, and the second remaining capacity SOC2 is relatively low. In the high state, the range of the required driving force DT_dmd for supplying electric power from the first power storage device 2 to the electric motor 100 is expanded as compared with the first control mode.

  More specifically, in the third control mode in the present embodiment, the upper limit threshold B2_th1 of the middle remaining capacity region of the second remaining capacity SOC2 is set in advance to a value lower than in the first control mode.

  Further, the basic power supply amount P1_base of the first power storage device 2 in the low remaining capacity region and the medium remaining capacity region of the second power storage device 3 is smaller than in the first control mode (in other words, the basic power supply amount P1_base is The threshold value DT_th4 (converted value when the rotation speed is constant) converted into a driving force value according to the rotation speed of the motor 100 is smaller than that in the first control mode), and the second remaining capacity SOC2 is Set according to the detected value.

  Such a basic power supply amount P1_base can be determined in the same manner as in the first control mode. For example, similarly to the case of the first control mode, the basic power supply amount P1_base (= α × P1b) can be determined by the same processing as the processing shown in the flowchart of FIG. However, in this case, the maximum value P1b of the basic power supply amount P1_base is set in advance to a value smaller than that in the first control mode.

  Note that the basic power supply amount P1_base in the third control mode can also be directly set, for example, from a detected value of the second remaining capacity SOC2 using a map or an arithmetic expression created in advance.

  In the third control mode, the threshold value DT_th1 of the required driving force DT_dmd in the high remaining capacity region and the threshold value DT_th2 of the required driving force DT_dmd in the medium remaining capacity region are both smaller than those in the first control mode. Is set to

  The manner of setting the threshold values for the second remaining capacity SOC2 and the required driving force DT_dmd in the third control mode is the same as in the first control mode except for the items described above.

  The normal combination control process in the third control mode is executed according to the flowcharts of FIGS. 6 to 8 as in the first control mode.

  The normal combination control process in the third control mode is executed as described above.

  In the third control mode, the remaining capacity area (lower remaining capacity area) combining the low remaining capacity area and the middle remaining capacity area is narrower than in the first control mode, and the first power storage device is provided in the remaining capacity area. The range of the required driving force DT_dmd in which charging of the second power storage device 3 from 2 is performed is smaller than that in the first control mode. Therefore, a state in which the first power storage device 2 charges the second power storage device 3 is less likely to occur.

  For this reason, the power loss due to the charging can be reduced as compared with the first control mode and the second control mode. As a result, the amount of electric energy consumed by the entire first power storage device 2 and second power storage device 3 per unit traveling distance of the vehicle can be reduced as compared with the first control mode and the second control mode. As a result, the cruising distance of the vehicle can be extended.

  In the present embodiment, both the upper limit threshold value B2_th1 of the middle remaining capacity region of the second remaining capacity SOC2 and the basic power supply amount P1_base of the first power storage device 2 are set to values smaller than those in the first control mode. , One of the threshold value B2_th1 and the basic power supply amount P1_base may be set to a value smaller than that in the first control mode. Even in this case, the area in which the first power storage device 2 is charged to the second power storage device 3 can be made smaller than in the first control mode.

  When the first to third control modes described above are arranged, the first control mode is a so-called “long-lasting mode” whose main purpose is to minimize deterioration of the first power storage device 2 and the second power storage device 3. . The second control mode is a so-called “sports mode” whose main purpose is to increase the responsiveness of the electric motor 100 to the required driving force DT_dmd. The third control mode is a so-called “eco mode” whose main purpose is to increase the power consumption performance of the vehicle (the cruising distance of the vehicle per unit consumption of electric energy).

(Stop extension control processing)
Next, the stop extension control processing in STEP 6 will be described in detail.

  In the stop extension control process, the power transmission control unit 41 performs the power supply operation from the first power storage device 2 to the electric motor 100 as continuously as possible during the power running operation of the electric motor 100, while deficient in the power supply amount corresponding to the required driving force DT_dmd. The power transmission circuit unit 11 is controlled so that only the power is supplied from the second power storage device 3 to the electric motor 100.

  In the stop extension control processing, the power transmission control unit 41 executes the processing shown in the flowchart of FIG. 13 at a predetermined control processing cycle. Specifically, in STEP 41, the power transmission control unit 41 determines an upper limit power supply amount P1_max that can be output from the first power storage device 2 according to the detected value of the first remaining capacity SOC1.

  The upper limit power supply amount P1_max is determined, for example, in a form shown in a graph of FIG. The upper limit power supply amount P1_max is determined to be smaller as SOC1 is smaller.

  Next, the power transmission control unit 41 determines in STEP 42 whether or not the upper limit power supply amount P1_max is larger than the power supply amount corresponding to the required driving force DT_dmd.

  If the determination result in step 42 is affirmative, the power transmission control unit 41 determines in step 43 that the power P1 of the first power storage device 2 matches the power supply amount corresponding to the required driving force DT_dmd. The transmission circuit section 11 is controlled.

  The specific control of the power transmission circuit unit 11 in this case can be performed in the same manner as in STEP 28 of FIG.

  On the other hand, if the determination result in STEP 42 is negative, in STEP 44, the power transmission control unit 41 determines that the output P1 of the first power storage device 2 matches the upper limit power supply amount P1_max and that the second power storage device 3 The power transmission circuit unit 11 is controlled so that the output P2 of the first power storage device 2 matches the shortage of the power supply amount obtained by subtracting the output P1 (= P1_max) of the first power storage device 2 from the power supply amount corresponding to the required driving force DT_dmd.

  In this case, specific control of the power transmission circuit unit 11 can be performed in the same manner as in STEP 14 of FIG.

  In STEP44, when the detected value of the first remaining capacity SOC1 has reached the lower limit value B1_min and the upper limit power supply amount P1_max = 0, the power supply amount corresponding to the required driving force DT_dmd from only the second power storage device 3 is provided. Is supplied to the electric motor 100. In this situation, the voltage converter 15 of the power transmission circuit unit 11 is controlled to be in a power cutoff state, or the contactor 12 of the first power storage device 2 is controlled to be in an off state.

  The stop extension control process is executed as described above. In the stop extension control process, power is supplied to the electric motor 100 by preferentially using the first power storage device 2 that is difficult to output a large power supply amount. Then, even when the upper limit power supply amount P1_max that can be output by the first power storage device 2 is less than the power supply amount corresponding to the required driving force DT_dmd, power is supplied from both the first power storage device 2 and the second power storage device 3 to the electric motor 100. By doing so, the first power storage device 2 can be discharged to the remaining capacity of the lower limit B1_min.

  Then, thereafter, the electric power is supplied from the second power storage device 3 to the electric motor 100, which easily outputs a large power supply amount, so that the second power storage device 3 is discharged to the remaining capacity of the lower limit B2_min or the remaining capacity close thereto. be able to.

  Here, an example of how the first remaining capacity SOC1 and the second remaining capacity SOC2 change by the above-described normal combination control processing and the stop extension control processing will be described with reference to FIGS. Will be explained.

  In this example, the control mode in the normal combination control process is, for example, the first control mode.

  A graph S shown in FIG. 14 shows that the combination of the first remaining capacity SOC1 and the second remaining capacity SOC2 changes in any pattern while the vehicle is running while executing the normal combined control processing. This is an example.

  As can be seen from the graph S, the second remaining capacity SOC2 is maintained at, for example, a value near the threshold value B2_th1 by appropriately charging the first power storage device 2 to the second power storage device 3. While increasing or decreasing, the first remaining capacity SOC1 decreases.

  Bold arrows a1 to a4 in FIG. 14 indicate, for example, the cruise running of the vehicle from the point in time when the set of the first remaining capacity SOC1 and the second remaining capacity SOC2 is at the point Q (time t0). This shows how the set of the first remaining capacity SOC1 and the second remaining capacity SOC2 changes in the case of the above. The cruise traveling is a traveling of the vehicle in a state where the required driving force DT_dmd and the rotation speed of the electric motor 100 are kept almost constant.

  Then, the point b1 and the bold arrows b2 to b4 in FIG. 15 indicate the change of the first remaining capacity SOC1 from the time t0, and the bold arrows c1 and c2, the point c3, and the bold arrow c4 in FIG. The change of the second remaining capacity SOC2 from the time t0 is shown.

  a1, b1, c1 are the period from time t0 to t1, a2, b2, c2 are the period from time t1 to t2, a3, b3, c3 are the period from time t2 to t3, a4, b4, c4 Is for a period after time t3. The time t3 is a time at which the stop extension control process is started when the first remaining capacity SOC1 reaches the threshold value B1_th1. In addition, the required driving force DT_dmd of the electric motor 100 during the cruise traveling is, for example, a value at the height position of c1, c2, c3, and c4 in FIG.

  In the period from time t0 to time t1, power is not supplied from the first power storage device 2 to the electric motor 100 or the second power storage device 3 is charged by the normal combination control process in the first control mode, and the second power storage device 3 is not operated. The electric power is supplied to the electric motor 100 only from this (see FIG. 16). Therefore, as exemplified by the arrow a1 in FIG. 14 and the point b1 in FIG. 15, the first remaining capacity SOC1 is kept constant. Further, as exemplified by the arrow a1 in FIG. 14 and the arrow c1 in FIG. 16, the second remaining capacity SOC2 decreases.

  When the second remaining capacity SOC2 reaches the threshold value B2_th1 at time t1, next, during the period from time t1 to t2, the first power storage device 2 and the second power storage device 3 are controlled by the normal combination control process in the first control mode. Power is supplied to the electric motor 100 from both (see FIG. 16). Therefore, as illustrated by the arrow a2 in FIG. 14 and the arrow b2 in FIG. 15, the first remaining capacity SOC1 decreases, and as illustrated by the arrow a2 in FIG. 14 and the arrow c2 in FIG. 2 The remaining capacity SOC2 decreases.

  At time t2, when second remaining capacity SOC2 reaches a value corresponding to point c3 in FIG. 16, power is supplied to electric motor 100 only from first power storage device 2 by the normal combination control process in the first control mode. become. Therefore, in the period from the time t2 to the time t3, the second remaining capacity SOC2 is kept constant as exemplified by the arrow a3 in FIG. 14 and the point c3 in FIG. Then, as exemplified by the arrow a3 in FIG. 14 and the arrow b3 in FIG. 15, the first remaining capacity SOC1 decreases.

  At time t3, when the first remaining capacity SOC1 decreases to the threshold value B1_th1, the stop extension control process is started. For this reason, after time t3, as illustrated by the arrow a4 in FIG. 14 and the arrow b4 in FIG. 15, while the first power storage device 2 outputs the upper limit power supply amount P1_max, the first remaining capacity SOC1 decreases to the lower limit value B1_min. To decrease. Further, as exemplified by the arrow a4 in FIG. 14 and the arrow c4 in FIG. 16, the second remaining capacity SOC2 decreases to the lower limit value B2_min.

  FIG. 17 shows an example of a temporal change of the first remaining capacity SOC1 and the second remaining capacity SOC2 in the stop extension control process. In the illustrated example, after the start of the stop extension control process, the first remaining capacity SOC1 and the first remaining capacity SOC1 in a state where the output (power supply amount) to the electric motor 100 is maintained at a constant value (that is, the cruising state of the vehicle). 2 shows an example of a temporal change of the remaining capacity SOC2.

  As shown in the drawing, by supplying power to the electric motor 100 from both the first power storage device 2 and the second power storage device 3, the first power storage device 2 and the The remaining capacity SOC1 and SOC2 of the second power storage device 3 can be consumed up to the respective lower limit values B1_min and B2_min.

  By extending the period during which power can be supplied to electric motor 100 by both first power storage device 2 and second power storage device 3 as described above, the period during which power can be supplied only to one power storage device (for example, first power storage device 2). Since the power of both the first power storage device 2 and the second power storage device 3 can be sufficiently used as compared with the case where the length of the vehicle is extended, the period during which power can be supplied to the electric motor 100 and the cruising distance of the vehicle can be further reduced. Can be extended.

  As described above, especially in the normal combined control process in the first control mode, the first remaining capacity SOC1 is reduced while the second remaining capacity SOC2 is maintained in the middle remaining capacity region or a value in the vicinity thereof. You can do so.

  In the stop extension control process, the first power storage device 2 and the second power storage device 3 are sufficiently discharged to the respective lower limit values B1_min and B2_min by the power supply to the electric motor 100, or to the remaining capacity values close thereto. be able to.

  The normal combination control process and the stop extension control process described above are processes executed when both the first power storage device 2 and the second power storage device 3 are normal (there is no failure).

  At the time of power running operation of the electric motor 100 when the first power storage device 2 is normal and the second power storage device 3 is in a failure state, the power transmission control unit 41 operates the contactor 13 on the second power storage device 3 side. In the off state, the voltage converter 15 and the inverter 17 of the power transmission circuit unit 11 are configured to supply the electric power corresponding to the required driving force DT_dmd of the electric motor 100 to the electric motor 100 only from the first power storage device 2. Control. The control process of the power transmission circuit unit 11 in this case is executed in the same manner as in STEP28.

(Control processing during braking)
Next, a control process of the power transmission control unit 41 in a situation where the electric motor 100 is braked (when the vehicle is decelerated) will be described.

  In the present embodiment, when the electric motor 100 is braked, the power transmission control unit 41 executes the processing shown in the flowchart of FIG. 18 at a predetermined control processing cycle. Note that this process is a process when the first power storage device 2 is normal.

  In this process, first, the power transmission control unit 41 determines whether or not the electric power is to be controlled based on the failure detection information of the second power storage device 3 (detection information of the presence or absence of a failure) and the detected value of the remaining capacity SOC1 of the first power storage device 2. A braking processing mode that defines a mode of control processing for braking the motor 100 is set.

  Specifically, in STEP 51, the power transmission control unit 41 acquires the failure detection information of the second power storage device 3 from the failure detection unit 43, and also acquires the remaining capacity SOC1 (first remaining capacity SOC1) of the first power storage device 2. From the remaining capacity detection unit 42.

  Next, in STEP 52, the power transmission control unit 41 determines whether or not the failure detection information is information indicating a state in which the second power storage device 3 has no failure (normal state).

  When the determination result is affirmative (when the second power storage device 3 is normal), the power transmission control unit 41 sets the braking processing mode to the first braking mode in STEP53. Although the details will be described later, the first braking mode realizes the required braking force of the electric motor 100 by the regenerative braking force generated by the regenerative operation of the electric motor 100, and generates the regenerative power output by the electric motor 100, In this mode, one or both of the first power storage device 2 and the second power storage device 3 (mainly, the second power storage device 3) are charged based on a map as shown in FIG. 19A.

  When the determination result in STEP 52 is negative (when the failure of the second power storage device 3 is detected), the power transmission control unit 41 resets the contactor 13 on the second power storage device 3 side in STEP 55. Turn off (cut off). Thus, charging and discharging of the second power storage device 3 is prohibited.

  Further, in STEP 56, the power transmission control unit 41 determines whether or not the detected value of the first remaining capacity SOC1 is equal to or more than a predetermined remaining capacity threshold B1_th2.

  The situation in which the determination result in STEP 56 is affirmative is such that the vehicle can continue traveling (powering operation of the electric motor 100) for a while without charging the first power storage device 2 with regenerative power. This is a situation where one remaining capacity SOC1 is relatively large. In other words, since the first power storage device 2 is fully charged or nearly full, it is not necessary to charge the first power storage device 2 from the viewpoint of suppressing deterioration due to charging.

  In this situation, the power transmission control unit 41 sets the braking processing mode to the second braking mode in STEP 57. Although described in detail later, the second braking mode is a mode in which the required braking force of the electric motor 100 is realized only by the braking force of the braking device 6 without performing the regenerative operation of the electric motor 100.

  Further, the situation in which the determination result in STEP 56 is negative is that the first remaining capacity SOC1 is relatively small, and when the running of the vehicle (powering operation of the electric motor 100) is continued, the first remaining capacity SOC1 is relatively early. This is a situation in which there is a high possibility that the remaining capacity SOC <b> 1 becomes insufficient and it becomes difficult to continue running the vehicle (power running operation of the electric motor 100).

  In this situation, in STEP 58, the power transmission control unit 41 sets the braking processing mode to the third braking mode. Although the details will be described later, the third braking mode is realized by the required braking force of the electric motor 100 by the regenerative braking force or by both the regenerative braking force and the braking force by the braking device 6 (non-regenerative braking force). In this mode, the first power storage device 2 is charged with a relatively small amount of regenerative power output from the electric motor 100.

  After setting the braking process mode as described above, the power transmission control unit 41 executes a braking process for applying a braking force to the electric motor 100 in STEP 54 according to the set braking process mode.

  Next, the braking process in each of the first braking mode, the second braking mode, and the third braking mode will be specifically described.

(Brake process in first brake mode)
In the braking process in the first braking mode, the power transmission control unit 41 executes the process shown in the flowchart of FIG.

  Specifically, in STEP54-1, the power transmission control unit 41 acquires the detected value of the remaining capacity SOC2 (second remaining capacity SOC2) of the second power storage device 3 and the required regeneration amount G_dmd of the electric motor 100. . In the present embodiment, the required regenerative amount G_dmd is the power generated by the electric motor 100 (per unit time) assuming that the required braking force of the electric motor 100 is realized only by the regenerative braking force during the regenerative operation of the electric motor 100. Power generation energy).

  The required regeneration amount G_dmd is obtained, for example, from a required braking force of the electric motor 100 and a detected value of the rotation speed of the electric motor 100 by using a map or an arithmetic expression created in advance.

  Next, in STEP 54-2, the power transmission control unit 41 uses the detected value of the SOC2 and the required regeneration amount G_dmd of the electric motor 100 based on a map created in advance, based on the first power storage device 2 and the second power storage device. 3 to determine the respective target inputs Pc1 and Pc2 (target charge amounts). The target inputs Pc1 and Pc2 are determined such that the sum thereof matches the required regenerative amount G_dmd (therefore, the regenerative braking force of the electric motor 100 matches the required braking force).

  FIG. 19A visually represents the map. In this map, the stippled area where the required regeneration amount G_dmd is equal to or less than the predetermined threshold G_th1 represents an area where only the second power storage device 3 is charged with regenerative power (an area where Pc1 = 0), and the required regeneration amount G_dmd is A hatched area that is larger than the threshold G_th1 indicates an area in which both the first power storage device 2 and the second power storage device 3 are charged with regenerative power.

  The threshold value G_th1 is a threshold value set according to the detected value of the second remaining capacity SOC2. In the illustrated example, the threshold value G_th1 is a predetermined constant value (fixed value) in an area where the second remaining capacity SOC2 is equal to or less than the predetermined value SOC2a, and is equal to the second remaining capacity SOC2 in an area larger than the predetermined value SOC2a. Is set so as to decrease as the number increases. The threshold value G_th1 in a region equal to or less than the predetermined value SOC2a is set to a value close to the maximum value G_max of the required regeneration amount G_dmd.

  In STEP 54-2, when the set of the detected value of SOC2 and the required regeneration amount G_dmd belongs to the stippling region, the target input Pc1 of the first power storage device 2 is set to zero, and the second power storage device is set. The required regeneration amount G_dmd is set as the target input Pc2 of No. 3. Therefore, when the required regeneration amount G_dmd is smaller than the threshold value G_th1, the target inputs Pc1 and Pc2 are set so that only the second power storage device 3 is charged with the regenerative power.

  If the set of the detected value of SOC2 and the required regeneration amount G_dmd belongs to the shaded area, the regeneration amount that matches the threshold value G_th1 is set as the target input Pc2 of the second power storage device 3 and the required regeneration amount is set. The remaining regenerative amount obtained by subtracting the target input Pc2 of the second power storage device 3 from the regenerative amount G_dmd is set as the target input Pc1 of the first power storage device 2.

  Therefore, when the required regeneration amount G_dmd is greater than the threshold value G_th1 and the detected value of the second remaining capacity SOC2 is greater than the predetermined value SOC2a, the target input of the second power storage device 3 in the required regeneration amount G_dmd The ratio of Pc2 is set to decrease as the detected value of SOC2 is increased (in other words, the ratio of target input Pc1 of first power storage device 2 in required regeneration amount G_dmd is increased as the detected value of SOC2 is increased). Target inputs Pc1, Pc2 are set.

  Next, in STEP 54-3, the power transmission control unit 41 determines whether or not the required regeneration amount G_dmd is larger than the threshold G_th1.

  The situation in which the determination result in STEP 53 is affirmative is the situation in the hatched area in FIG. 19A. In this situation, in STEP54-4, the power transmission control unit 41 controls the power transmission circuit unit 11 to charge the first power storage device 2 and the second power storage device 3 with the target inputs Pc1 and Pc2, respectively.

  Specifically, the processing in STEP 54-4 can be executed, for example, as follows. That is, a target value of the output voltage of the inverter 17 (= input voltage of the voltage converters 15 and 16) is set according to the detected value of the rotation speed of the electric motor 100 and the like. Further, the target input Pc1 is set as a target value of output power from the voltage converter 15 to the first power storage device 2, and the target input Pc2 is set as a target value of output power from the voltage converter 16 to the second power storage device 3. Is set as

  Then, the inverter 17 is controlled so as to realize the target value of the output voltage of the inverter 17. At the same time, the voltage converters 15 and 16 are controlled so as to achieve the target value of the output power from each of the voltage converters 15 and 16 to each of the first power storage device 2 and the second power storage device 3.

  On the other hand, the situation in which the determination result in STEP 54-3 is negative is the situation in the stippling area in FIG. 19A. In this situation, in STEP54-5, the power transmission control unit 41 controls the power transmission circuit unit 11 to charge only the second power storage device 3 with the target input Pc2.

  Specifically, the processing in STEP 54-5 can be executed, for example, as follows. That is, the target value of the output voltage of the inverter 17 (= input voltage of the voltage converter 16) is set according to the detected value of the rotation speed of the electric motor 100 and the like. Further, target input Pc2 is set as a target value of output power from voltage converter 16 to second power storage device 3.

  Then, the inverter 17 is controlled so as to realize the target value of the output voltage of the inverter 17. At the same time, the voltage converter 16 is controlled so as to achieve the target value of the output power from the voltage converter 16 to the second power storage device 3.

  Further, the voltage converter 15 is controlled to be in a power cutoff state. Alternatively, contactor 12 of first power storage device 2 is controlled to be in the off state. Thus, discharging from the first power storage device 2 to the second power storage device 3 and charging from the inverter 17 to the first power storage device 2 are prohibited.

  As described above, the braking process in the first braking mode is performed by the power transmission control unit 41.

  By executing the braking process in the first braking mode as described above, the regenerative operation of the electric motor 100 is performed so that the required braking force of the electric motor 100 is realized by the regenerative braking force of the electric motor 100.

  At this time, the regenerative power output from the electric motor 100 is basically charged in the second power storage device 3. Then, only the regenerative power that cannot be fully charged in second power storage device 3 (the amount of regeneration exceeding threshold value G_th1) is charged in first power storage device 2.

  Thereby, while minimizing the occurrence of a situation in which the first power storage device 2 needs to charge the second power storage device 3, the second remaining capacity SOC <b> 2 is reduced in the middle remaining capacity region or in the vicinity thereof. The capacitance value can be maintained. As a result, the energy use efficiency of the entire system increases.

  Although the first power storage device 2 generally has low deterioration resistance to high-rate charging (high-speed charging with a large amount of charge per unit time), the first power storage device 2 reduces the regenerative amount to the first power storage device as much as possible. 1 The deterioration of the power storage device 2 can be suppressed as much as possible.

(Brake process in second brake mode)
Next, in the braking processing in the second braking mode, the power transmission control unit 41 executes the processing shown in the flowchart of FIG.

  Specifically, the power transmission control unit 41 acquires the required regeneration amount G_dmd of the electric motor 100 in STEP 54-11.

  Then, in STEP54-12, the power transmission control unit 41 sets the target braking force Br_cmd of the braking device 6. In this case, a braking force corresponding to the required regeneration amount G_dmd, that is, a required braking force of the electric motor 100 is set as the target braking force Br_cmd.

  Next, in STEP54-13, the power transmission control unit 41 instructs the braking device control unit 44 of the target braking force Br_cmd. At this time, the braking device control unit 44 controls the braking device 6 so as to apply the target braking force Br_cmd to the electric motor 100.

  As described above, the braking process in the second braking mode is executed by the power transmission control unit 41.

  In the second braking mode, since the electric motor 100 does not perform the regenerative operation, the power transmission control unit 41 maintains both of the voltage converters 15 and 16 in the power cutoff state, or both of the contactors 12 and 13. Is kept off.

  As described above, when the second power storage device 3 fails in a state where the first remaining capacity SOC1 is equal to or more than the predetermined remaining capacity threshold B1_th2, the braking process in the second braking mode is performed, as shown in FIG. 19B. As described above, the braking device 6 is controlled such that the braking force corresponding to the required regeneration amount G_dmd (= the required braking force of the electric motor 100) is realized only by the braking force of the braking device 6. Therefore, the share of the regenerative braking force in the required braking force is set to zero.

  Note that in FIG. 19B, the horizontal axis represents the value of the second remaining capacity SOC2 in order to match with FIG. 19A. However, in the second braking mode, the second remaining power storage device 3 is out of order. No value for SOC2 is required.

  In the second braking mode, charging of the first power storage device 2 by the regenerative operation of the electric motor 100 is not performed, so that deterioration of the first power storage device 2 due to charging can be prevented from progressing.

  In addition, in a situation where the braking process in the second braking mode is performed when the electric motor 100 is braked, the remaining capacity SOC1 of the first power storage device 2 is relatively large. The power supply amount corresponding to the required driving force DT_dmd from the device 2 can be continuously supplied to the electric motor 100.

(Braking process in the third braking mode)
Next, in the braking process in the third braking mode, the power transmission control unit 41 executes the process shown in the flowchart of FIG.

  Specifically, the power transmission control unit 41 obtains the required regeneration amount G_dmd of the electric motor 100 in STEP54-21.

  Next, in STEP54-22, the power transmission control unit 41 determines whether or not the required regeneration amount G_dmd of the electric motor 100 is equal to or less than a predetermined threshold G_th3.

  The threshold value G_th3 is a threshold value set to coincide with an upper limit of a charge amount (a charge amount per unit time) that is desirable for preventing deterioration of the first power storage device 2 due to charging as much as possible.

  Here, FIG. 23 shows a charging rate (unit is, for example, [C]) indicating a charging speed (a charging amount per unit time) at the time of charging the first power storage device 2 and deterioration of the capacity of the first power storage device 2. 5 is a graph illustrating a relationship with a capacity deterioration coefficient indicating a degree. The capacity deterioration coefficient is a value calculated by a so-called route rule. Charging at a charging rate of 1 [C] means constant-current charging with a current amount that can complete charging of a discharged power storage device in 1 [h]. For example, assuming that the nominal capacity of the power storage device is X [Ah], charging at a charge rate of 1 [C] means constant current charging at X [A].

  As shown in FIG. 23, when the first power storage device 2 is charged at a high rate at which the charge rate becomes higher than the predetermined value Crx, the charge rate becomes lower at a lower rate at which the charge rate becomes lower than the predetermined value Crx. As compared with the case where the first power storage device 2 is charged, the increase in the capacity deterioration coefficient (the increase in the degree of deterioration of the first power storage device 2) with respect to the increase in the charging rate increases sharply.

  Therefore, in the present embodiment, a charging rate equal to or lower than the predetermined value Crx is set as an allowable range of the charging speed of the first power storage device 2. If the threshold value G_th3 in the determination process in STEP54-22 is a regeneration amount equal to or less than the threshold value G_th3, the first power storage device 2 is charged at a charge rate equal to or less than a predetermined value Crx (a charge rate within an allowable range). Is set to get.

  The situation where the judgment result of STEP54-22 is affirmative is a situation where the regenerative power of the required regeneration amount G_dmd can be charged in the first power storage device 2 within the allowable range of the charging rate. In this case, the power transmission control unit 41 sets the required regeneration amount G_dmd as the target input Pc1 of the first power storage device 2 in STEP54-23.

  Then, in STEP54-24, the power transmission control unit 41 controls the power transmission circuit unit 11 so as to charge the first power storage device 2 with the target input Pc1.

  The processing in STEP54-24 can be specifically executed as follows, for example. That is, the target value of the output voltage of the inverter 17 (= input voltage of the voltage converter 15) is set according to the detected value of the rotation speed of the electric motor 100 and the like. Further, target input Pc1 is set as a target value of output power from voltage converter 15 to first power storage device 2.

  Then, the inverter 17 is controlled so as to realize the target value of the output voltage of the inverter 17. At the same time, the voltage converter 15 is controlled so as to achieve a target value of output power from the voltage converter 15 to the first power storage device 2. In this case, the contactor 13 on the second power storage device 3 side is turned off.

  In the situation where the determination result in STEP 54-22 is negative, if the regenerative power of the required regeneration amount G_dmd is to be charged to the first power storage device 2 as it is, the first power storage device 2 may be charged within the allowable range of the charging rate. It is not possible. In this case, in STEP54-25, the power transmission control unit 41 sets the threshold G_th3 as the target input Pc1 of the first power storage device 2, and sets the required regenerative amount G_dmd as the target braking force Br_cmd of the braking device 6. A braking force corresponding to the remaining regeneration amount obtained by subtracting the threshold value G_th3 (= Pc1) from is set.

  This braking force (= Br_cmd) is a braking force that matches the regenerative braking force generated by the electric motor 100, assuming that the regenerative operation of the electric motor 100 has been performed with the remaining amount of regeneration. Such a braking force can be obtained from a residual regeneration amount (= G_dmd-G_th3) and a detected value of the rotation speed of the electric motor 100 by using a map or an arithmetic expression created in advance.

  Therefore, in STEP54-25, the total braking force of the regenerative braking force generated when the electric motor 100 performs the regenerative operation with the regenerative amount of the threshold G_th3 and the target braking force Br_cmd becomes equal to the required amount of the electric motor G_dmd. The target braking force Br_dmd is set so as to match the regenerative braking force generated when it is assumed that 100 regenerative operations have been performed.

  Next, in STEP54-26, the power transmission control unit 41 controls the power transmission circuit unit 11 so as to charge the first power storage device 2 with the target input Pc1, and also transmits the target braking force Br_cmd to the braking device control unit 44. Command. At this time, the braking device control unit 44 controls the braking device 6 so as to apply the target braking force Br_cmd to the electric motor 100. The control of the power transmission circuit unit 11 in STEP54-26 is performed in the same manner as in STEP54-24.

  As described above, the braking process in the third braking mode is executed by the power transmission control unit 41.

  By performing the braking process in the third braking mode as described above, when the required regeneration amount G_dmd is equal to or less than the threshold value G_th3, as shown in FIG. 19C, the braking force (= electric power) corresponding to the required regeneration amount G_dmd The required braking force of the motor 100) is realized only by the regenerative braking force generated by the electric motor 100 by charging the first power storage device 2 from the electric motor 100 with regenerative power that matches the required regeneration amount G_dmd. Then, the power transmission circuit unit 11 is controlled. In this situation, no braking force is generated by the braking device 6.

  When the required regeneration amount G_dmd is larger than the threshold value G_th3, the braking force (= requested braking force of the electric motor 100) corresponding to the required regeneration amount G_dmd is charged from the electric motor 100 to the first power storage device 2. Is performed with regenerative power that matches the threshold value G_th, so that the electric power transmission circuit unit 11 and the braking device 6 are connected to each other so that both the regenerative braking force generated by the electric motor 100 and the braking force of the braking device 6 are realized. Controlled.

  Note that in FIG. 19C, the horizontal axis represents the value of the second remaining capacity SOC2 in order to match with FIG. 19A. However, in the third braking mode, the second remaining power capacity 3 is broken, No value for SOC2 is required.

  In the third braking mode, the amount of charge (the amount of charge per unit time) of the first power storage device 2 by the regenerative operation of the electric motor 100 can charge the first power storage device 2 at a charge rate within an allowable range. The charge amount is limited to the threshold value G_th3 or less set as described above.

  For this reason, the regenerative electric power is charged to the first power storage device 2 within a range in which the progress of the deterioration of the first power storage device 2 can be sufficiently suppressed. As a result, during traveling of the vehicle in a state where the second power storage device 3 has failed, power can be supplied from the first power storage device 2 to the electric motor 100 while minimizing the progress of deterioration of the first power storage device 2. The period can be extended as much as possible.

  FIG. 24 is a graph showing changes with time in the remaining capacity SOC1 of the first power storage device 2 before and after the failure of the second power storage device 3 and the remaining capacity of the second power storage device 3 before the failure of the second power storage device 3 occurs. 6 is a graph exemplarily showing a change over time of a capacity SOC2.

  In FIG. 24, the failure of the second power storage device 3 occurs at time t1, and at time t2, the first remaining capacity SOC1 decreases to the remaining capacity threshold B1_th2. Accordingly, the period before time t1 is a period during which the braking process in the first braking mode is executed when the electric motor 100 is braked, and the period from time t1 to t2 is the period when the electric motor 100 is braked in the second braking mode during the braking. The period during which the braking process is performed, and the period after time t2, are the periods during which the braking process in the third braking mode is performed when the electric motor 100 is braked.

  In this case, after time t2, the period of Δt1 and the period of Δt2 are periods during which regenerative power is charged in first power storage device 2 during braking of electric motor 100. As described above, when the electric motor 100 is braked, the first power storage device 2 is charged with regenerative power, so that the first remaining capacity SOC1 is recovered to some extent. Therefore, the period during which power can be supplied to the electric motor 100 after time t2 can be extended as much as possible.

  Here, the correspondence between the first embodiment described above and the present invention will be supplemented.

In the present embodiment, the braking processing in the first braking mode corresponds to the processing of the reference example related to the first braking processing in the present invention, and the braking processing in the second braking mode and the braking processing in the third braking mode are performed. The braking process combined with the braking process corresponds to the second braking process in the present invention.

  Further, the required regeneration amount G_dmd during braking of the electric motor 100 (electric load) corresponds to the regeneration amount index value in the present invention.

  Further, the predetermined value Crx of the charging rate shown in FIG. 23 corresponds to a speed threshold relating to the charging speed in the present invention.

[Second embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS. This embodiment is different from the first embodiment only in the braking process in the first braking mode when the electric motor 100 is braked. Therefore, the description of the same items as in the first embodiment will be omitted.

  In the present embodiment, the braking process in the first braking mode at the time of braking the electric motor 100 is executed at a predetermined control processing cycle as shown in the flowchart of FIG.

  Specifically, in STEP 61, the power transmission control unit 41 acquires the detected value of the second remaining capacity SOC2 and the required regeneration amount G_dmd of the electric motor 100. The processing in STEP 61 is the same as the processing in STEP 54-1 in the first embodiment.

  Next, in STEP 62, the power transmission control unit 41 determines whether each of the first power storage device 2 and the second power storage device 3 is based on a map created in advance from the detected value of the SOC2 and the required regeneration amount G_dmd of the electric motor 100. Of the target inputs Pc1 and Pc2 (target charge amounts) are determined.

  FIG. 26 visually shows the map in the present embodiment. In this map, a hatched area where the required regeneration amount G_dmd is equal to or less than a predetermined threshold G_th2 represents an area where only the first power storage device 2 is charged (area where Pc2 = 0), and the required regeneration amount G_dmd is greater than the threshold G_th2. The stippling area where the threshold value is large and equal to or less than the predetermined threshold value G_th1, and the shaded area where the required regeneration amount G_dmd is larger than the threshold value G_th1 are used to charge both the first power storage device 2 and the second power storage device 3. This represents an area in which to perform.

  Of the threshold values G_th1 and G_th2, the threshold value G_th1 is a threshold value set according to the detected value of SOC2, as in the first embodiment.

  In the present embodiment, the threshold value G_th2 is a predetermined fixed value. The threshold G_th2 is a relatively small value (a value close to zero). As the threshold G_th2, for example, the threshold G_th3 used in the braking process in the third braking mode of the first embodiment can be used.

  In the above STEP 62, when the set of the detected value of SOC2 and the required regeneration amount G_dmd belongs to the lowermost shaded area, the target input Pc2 of the second power storage device 3 is set to zero and the first power storage The required regeneration amount G_dmd is set as the target input Pc1 of the device 2.

  Therefore, the target inputs Pc1 and Pc2 are set so that the regenerative power is charged only to the first power storage device 2.

  If the set of the detected value of SOC2 and the required regeneration amount G_dmd belongs to the stippling area, the regeneration amount that matches the threshold value G_th2 is set as the target input Pc1 of the first power storage device 2 and the required regeneration amount is set. The remaining regenerative amount obtained by subtracting the target input Pc1 of the first power storage device 2 from the regenerative amount G_dmd is set as the target input Pc2 of the second power storage device 3.

  If the set of the detected value of SOC2 and the required regeneration amount G_dmd belongs to the uppermost shaded area, a power supply amount that matches the threshold value G_th1 is set as the target input Pc2 of the second power storage device 3. At the same time, the remaining regeneration amount obtained by subtracting the target input Pc2 of the second power storage device 3 from the required regeneration amount G_dmd is set as the target input Pc1 of the first power storage device 2.

  Next, in STEP 63, the power transmission control unit 41 determines whether or not the required regeneration amount G_dmd is equal to or less than the threshold G_th2.

  The situation in which the result of determination in STEP 63 is affirmative is the situation in the lowermost hatched area in FIG. In this situation, in STEP 64, the power transmission control unit 41 controls the power transmission circuit unit 11 so that only the first power storage device 2 is charged with the target input Pc1.

  The processing in STEP 64 can be executed in the same manner as the processing in STEPs 54 to 24 in the third braking mode in the first embodiment.

  On the other hand, the situation in which the determination result in STEP 63 is negative is the situation in the stippling area or the uppermost hatched area in FIG. In this situation, in STEP 65, the power transmission control unit 41 controls the power transmission circuit unit 11 to charge the first power storage device 2 and the second power storage device 3 with the target inputs Pc1 and Pc2, respectively.

  The specific control processing of the power transmission circuit unit 11 in this case can be executed in the same manner as the processing of STEP 54-4 in the first braking mode in the first embodiment.

  In the present embodiment, as described above, the control process of the power transmission control unit 41 during the regenerative operation of the electric motor 100 is executed.

  By executing the control process of the power transmission control unit 41 during the regenerative operation as described above, a small amount of regenerative power equal to or less than the threshold G_th2 is stored in the first power storage device 2 except when the required regeneration amount is larger than the threshold G_th1. Charged. In this case, since the charge amount of first power storage device 2 is small, first power storage device 2 can be charged at a small charge rate (low rate). Therefore, during the regenerative operation, the first power storage device 2 can be charged while the progress of the deterioration of the first power storage device 2 is suppressed. As a result, the cruising distance of the vehicle can be extended.

  Also, the regenerative power exceeding the threshold G_th2 is charged in the second power storage device 3, so that the occurrence of a situation in which the first power storage device 2 needs to charge the second power storage device 3 is reduced. In such a case, the second remaining capacity SOC2 can be maintained at the remaining capacity value in the middle remaining capacity region or in the vicinity thereof.

  Here, the correspondence between the above-described second embodiment and the present invention will be supplemented.

In the present embodiment , the braking process in the first braking mode corresponds to the first braking process in the present invention, and the threshold G_th2 relating to the required regeneration amount G_dmd corresponds to the A-th threshold in the present invention. Except for this, the correspondence between the second embodiment and the present invention is the same as that of the first embodiment.

[Third embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG. This embodiment is different from the second embodiment only in the braking process in the first braking mode when the electric motor 100 is braked. Therefore, the description of the same items as in the second embodiment will be omitted.

  In the present embodiment, the control processing of the power transmission control unit 41 during the regenerative operation of the electric motor 100 is executed at a predetermined control processing cycle as shown in the flowchart of FIG.

  Specifically, in STEP 71, the power transmission control unit 41 acquires the detected value of the second remaining capacity SOC2 and the required regeneration amount G_dmd of the electric motor 100. The processing in STEP 71 is the same as the processing in STEP 51 of the first embodiment.

  Next, in STEP 72, based on a map created in advance from the detected value of SOC2 and the required regeneration amount G_dmd of the electric motor 100, the power transmission control unit 41 controls each of the first power storage device 2 and the second power storage device 3 respectively. Of the target inputs Pc1 and Pc2 (target charge amounts) are determined.

  In this case, the form of the above-described map in the present embodiment (area division by thresholds G_th1, G_th2) is the same as that of the second embodiment (shown in FIG. 26). However, in the present embodiment, the power storage device to be charged in the stippling region where the required regeneration amount G_dmd is larger than the threshold G_th2 and equal to or smaller than the threshold G_th1 is different from the second embodiment.

  That is, in the present embodiment, the stippling region in FIG. 26 is a region where only the second power storage device 3 is charged. When the set of the detected value of SOC2 and the required regeneration amount G_dmd belongs to the stippling region in FIG. 26, the target input Pc1 of the first power storage device 2 is set to zero, and the second power storage device 3 Is set as the target input Pc2.

  Note that the manner of setting the target inputs Pc1 and Pc2 in the lowermost hatched area and the uppermost hatched area in FIG. 26 is the same as in the second embodiment.

  Next, in STEP 73, the power transmission control unit 41 determines whether or not the required regeneration amount G_dmd is equal to or smaller than the threshold G_th2.

  The situation in which the result of determination in STEP 73 is affirmative is the situation in the hatched area at the bottom of FIG. In this situation, the power transmission control unit 41 controls the power transmission circuit unit 11 in STEP 74 so that only the first power storage device 2 is charged with the target input Pc1.

  The specific control process of the power transmission circuit unit 11 in this case can be executed in the same manner as the process of STEP 64 in the second embodiment.

  On the other hand, if the determination result in STEP 73 is negative, the power transmission control unit 41 further determines in STEP 75 whether the required regeneration amount G_dmd is larger than the threshold value G_th1.

  The situation in which the determination result in STEP 75 is affirmative is the situation in the hatched area at the top of FIG. In this situation, in STEP76, the power transmission control unit 41 controls the power transmission circuit unit 11 to charge the first power storage device 2 and the second power storage device 3 with the target inputs Pc1 and Pc2, respectively.

  The specific control processing of the power transmission circuit unit 11 in this case can be executed in the same manner as the processing of STEP 54-4 in the first embodiment.

  The situation where the determination result of STEP 75 is negative is the situation of the stippling area in FIG. In this case, in step 77, the power transmission control unit 41 controls the power transmission circuit unit 11 so that only the second power storage device 3 is charged with the target input Pc2.

  The specific control processing of the power transmission circuit unit 11 in this case can be executed in the same manner as the processing of STEP 54-5 in the first embodiment.

  In the present embodiment, as described above, the control process of the power transmission control unit 41 during the regenerative operation of the electric motor 100 is executed.

  By executing the control process of the power transmission control unit 41 during the regenerative operation as described above, when the required regeneration amount is a small regeneration amount equal to or less than G_th2, the power of the small regeneration amount is reduced to the first power storage device 2. Is charged. In this case, similarly to the second embodiment, the first power storage device 2 can be slowly charged at a small charge rate, so that the deterioration of the first power storage device 2 is suppressed while the first power storage device 2 Charging can be performed. As a result, the cruising distance of the vehicle can be extended.

  When the required regeneration amount is larger than G_th2, only the second power storage device 3 is charged with the regenerative power corresponding to the required regeneration amount unless the required regeneration amount exceeds the threshold G_th1. In this case, the deterioration of the second power storage device 3 does not easily occur even if the second power storage device 3 is not charged at a low charge rate, and therefore, the second power storage device 3 can be charged quickly. Therefore, the stability of the control of the power transmission circuit unit 11 during the regenerative operation can be improved.

  Note that the correspondence between this embodiment and the present invention is the same as that of the second embodiment.

  Supplementally, in the second embodiment or the third embodiment, when the required regeneration amount G_dmd is larger than the threshold G_th1, the difference between the threshold Gth1 and the threshold G_th2 is set as the target input Pc2 of the second power storage device 3. A regenerative amount (a regenerative amount obtained by subtracting a regenerative amount matching the threshold value G_th2 from a regenerative amount matching the threshold value G_th1) is set. The regeneration amount may be set as the target input Pc1 of the first power storage device 2.

[Modification]
Next, some modifications related to the above-described first to third embodiments will be described.

  In the above embodiments, in the braking process of the first braking mode when both the first power storage device 2 and the second power storage device 3 are normal (there is no failure), the required braking force of the electric motor 100 is regenerated. It was realized only by power. However, in the braking process of the first braking mode, part or all of the required braking force may be temporarily borne by the braking force (non-regenerative braking force) of the braking device 6. For example, in a situation where the state of charge SOC1 of the second power storage device 3 is close to the value in the fully charged state, a part or all of the required braking force is reduced by the braking force of the braking device 6 (non-regenerative braking force). May be borne.

  In the braking process in the first braking mode, the ratios of the charged amounts of the first power storage device 2 and the second power storage device 3 during the regenerative operation of the electric motor 100 are determined by the first remaining capacity SOC1 and the second remaining capacity. It is also possible to adjust according to only one of SOC2. Further, the ratio of the charge amount can be changed according to the respective temperatures of first power storage device 2 and second power storage device 3.

  In each of the above embodiments, in the braking process in the third braking mode, the upper limit value of regenerative power for charging the first power storage device 2 (that is, the regenerative amount corresponding to the threshold value G_th3) is set to a constant value. However, the upper limit of the regenerative power may be changed according to, for example, the remaining capacity SOC1 of the first power storage device 2 or the temperature. For example, the upper limit value of the regenerative power may be increased as remaining capacity SOC <b> 1 of first power storage device 2 is smaller, or may be lower as the temperature of first power storage device 2 is lower.

  Further, in each of the embodiments, the power supply system 1 that controls the power transmission circuit unit 11 in the three control modes of the first to third control modes when the electric motor 100 is in the power running operation has been described. However, the number of control modes of the power transmission circuit unit 11 during the power running operation of the electric motor 100 may be two or four or more. Furthermore, the power supply system 1 may be configured to perform the power transmission circuit unit 11 only in one of the first to third control modes.

  Further, the different control modes during the power running operation of the electric motor 100 may be different only in one of the basic power supply amount P1_base and the threshold value B2_th1 relating to the second remaining capacity. For example, only one of the maximum value P1b of the basic power supply amount P1_base and the threshold value B2_th1 adds a control mode different from the first control mode, or employs the control mode instead of the second control mode or the third control mode. It may be.

  Further, the stop extension control process may be omitted.

  In each of the above embodiments, the required driving force DT_dmd of the electric motor 100 is used as the required output of the electric motor 100 (electric load). However, for example, the amount of energy to be supplied to the electric motor 100 per unit time corresponding to the required driving force DT_dmd, or the required value of the energizing current of the electric motor 100 corresponding to the required driving force DT_dmd (the charge per unit time) The required value of the amount) can be used as the required output of the electric motor 100 (electric load).

  In each of the above embodiments, the required regeneration amount G_dmd of the electric motor 100 is used as the regeneration amount index value. However, for example, the required braking force of the electric motor 100 or the required value of the energizing current of the electric motor 100 corresponding to the required braking force can be used as the regeneration amount index value.

  In each of the above embodiments, the case where the electric load is the electric motor 100 has been described as an example. However, the electric load may be an electric load other than the electric motor 100 as long as it can output regenerative electric power.

  Further, the transport equipment on which the power supply system 1 is mounted is not limited to an electric vehicle. For example, the transportation device may be a hybrid vehicle, or may be a ship, a railway vehicle, or the like.

REFERENCE SIGNS LIST 1 power supply system 2 first power storage device 3 second power storage device 4 power transmission path 5 control device 6 braking device 11 power transmission circuit unit 15, 16 voltage converter , 17 ... Inverter, 100 ... Electric motor (electric load).

Claims (10)

A first power storage device and a second power storage device;
An electric load operable by receiving power supply from at least one of the first power storage device and the second power storage device and capable of outputting regenerative power without receiving the power supply; the first power storage device; A power transmission path is provided between the power storage device and the power storage device, and power transmission between the electric load and the first power storage device and the second power storage device can be controlled according to a given control signal. A power transmission circuit unit configured in
A braking device that generates a braking force applied to the electric load,
A control device having a function of controlling the power transmission circuit unit and the braking device, respectively .
The first power storage device is a power storage device having lower degradation resistance to charging than the second power storage device,
The control device includes:
Failure detection information indicating the presence or absence of a failure in each of the first power storage device and the second power storage device, and a required braking force at the time of braking the electric load, can be acquired;
When the electric load is braked when both the first power storage device and the second power storage device are in a failure-free state, one or both of the first power storage device and the second power storage device are charged with the regenerative power. The power transmission circuit unit and the braking unit are configured to satisfy the required braking force of the electric load by at least one of a regenerative braking force generated thereby and a non-regenerative braking force that is a braking force generated by the braking device. A first braking process that controls at least one of the devices, and includes a process that controls the power transmission circuit unit to charge at least a part of the regenerative power to the second power storage device. Functions to perform,
When the electric load is braked when the first power storage device is in a failure-free state and the second power storage device is in a faulty state, the regenerative power is generated by charging the one power storage device. At least one of the power transmission circuit unit and the braking device is controlled such that a required braking force of the electric load is satisfied by at least one of a regenerative braking force and a non-regenerative braking force generated by the braking device. a process of, along with are configured to have a function of executing a second braking process including a process of controlling the power transmission circuit unit to charge the regenerative electric power only to the first power storage device ,
In the first braking process, when the regenerative amount index value indicating the magnitude of the regenerative electric power to be output from the electric load at the time of braking the electric load is smaller than a predetermined A threshold, the regenerative electric power is reduced to the second electric power. When only one power storage device is charged and the regenerative amount index value is larger than the A threshold, the regenerative power is included in at least the second power storage device of the first power storage device and the second power storage device. It is configured to control the power transmission circuit unit to charge one or both power storage devices,
The A-th threshold is set such that, of the range equal to or less than the maximum value of the regeneration amount index value, a range smaller than the A-th threshold is a range narrower than a range larger than the A-th threshold. power supply system, characterized in that. The power supply system according to claim 1,
The first power storage device is a power storage device having a higher energy density than the second power storage device, and the second power storage device is a power storage device having a higher output density than the first power storage device. Power supply system. The power supply system according to claim 1 or 2 ,
The control device can acquire at least one of a regenerative amount index value indicating a magnitude of the regenerative electric power to be output from the electric load during braking of the electric load, and a remaining capacity of the second power storage device. In the first braking process, a ratio of a charge amount of the regenerative electric power to the first power storage device to a charge amount of the second electric power storage device is determined by the regenerative amount index value and the second power storage amount. A power supply system configured to control the power transmission circuit unit to change the power transmission circuit unit according to at least one of the remaining capacity of the device. The power supply system according to any one of claims 1 to 3 ,
The second braking process includes a process of controlling the power transmission circuit unit to charge the regenerative power only to the first power storage device and a process of controlling the braking device to generate the non-regenerative braking force. And a power supply system comprising: The power supply system according to claim 4 ,
In the second braking process, the control device controls the power transmission circuit unit to charge the regenerative electric power only to the first power storage device, and sets the charging speed of the first power storage device to a predetermined speed. The predetermined speed threshold is set to be less than or equal to a threshold, and the degree of deterioration of the first power storage device with respect to an increase in the charging speed in a speed range larger than the speed threshold is: A power supply system, wherein the threshold value is set in advance so as to be higher than a degree of progress of deterioration of the first power storage device with respect to an increase in the charging speed in a speed range smaller than the speed threshold. The power supply system according to claim 4 or 5 ,
The control device is capable of acquiring a remaining capacity of the first power storage device, and in the second braking process, assigns a share ratio of the regenerative braking force of the required braking force to a remaining capacity of the first power storage device. A power supply system, wherein the power supply system is configured to change in response to the change. The power supply system according to claim 6 ,
The control device, in the second braking process, when the remaining capacity of the first power storage device is larger than a predetermined remaining capacity threshold, the load ratio of the regenerative braking force of the required braking force to zero, The power supply system, wherein the braking device is controlled so that the non-regenerative braking force matches the required braking force. The power supply system according to any one of claims 1 to 7 ,
The power supply system, wherein the electric load is an electric motor. The power supply system according to claim 8 ,
The power transmission circuit unit includes a voltage converter that converts and outputs an output voltage of at least one of the first power storage device and the second power storage device, and the first power storage device or the second power storage device or the voltage. A power supply system, comprising: an inverter that converts DC power input from a converter into AC power and supplies power to the electric motor. Transport equipment comprising the power supply system according to any one of claims 1 to 9 .