JP5329366B2 - Electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric vehicle wherein a power storing device can be discharged without bringing discomfort to an occupant. <P>SOLUTION: The electric vehicle includes an equalization circuit 62 that discharges the stored power of at least one of multiple unit cells 76 by discharging resistors 78 respectively connected in parallel with the unit cells 76 to equalize the amounts of stored power of the unit cells 76, a parking time predicting means for predicting the parking time of the electric vehicle, and a stored power control means that discharges the stored power of the power storing device 60 through the equalization circuit 62 in accordance with the parking time predicted by the parking time predicting means and thereby reduces the stored power of the power storing device 60. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an electric vehicle driven by electric power from a power storage device having an assembled battery in which a plurality of unit cells are combined.

  An electric vehicle using a power storage device having an assembled battery in which unit cells such as a lithium ion battery are combined has been developed (for example, Patent Document 1). In Patent Document 1, when the ignition switch (40) is turned off in order to prevent performance deterioration of the power storage device in a state where the electric vehicle is stopped and the power storage device is neither charged nor discharged (soak state), The battery fan (24) and the air conditioner (AC) are operated to discharge the power storage device (4), and the power storage amount of the power storage device is reduced to a predetermined value or less (see, for example, the summary of Patent Document 1).

JP 2007-185005 A

  In Patent Document 1, since the power of the power storage device is consumed by operating the battery fan and the air conditioner, an operation sound of the battery fan or the air conditioner is generated, and there is a concern that the passenger may feel uncomfortable due to the operation sound.

  The present invention has been made in view of such problems, and an object of the present invention is to provide an electric vehicle capable of discharging a power storage device without giving a sense of incongruity to a passenger.

An electric vehicle according to the present invention is driven by electric power from a power storage device having an assembled battery in which a plurality of unit cells are combined, and the plurality of unit cells are connected to each of the plurality of unit cells in parallel. An equalization circuit that discharges at least one stored power among unit cells to equalize the amount of power stored in the plurality of unit cells; a parking time prediction unit that predicts a parking time of the electric vehicle; and the parking time prediction unit Storage power control means for discharging the stored power of the power storage device by the equalization circuit and reducing the stored power of the power storage device to a target stored power according to the parking time predicted by .

According to the present invention, according to the predicted parking time, the stored power of the power storage device is discharged by the discharge resistance of the equalization circuit to reduce the stored power of the power storage device. Since the discharge due to the discharge resistor does not accompany the operation sound, the stored power of the power storage device can be reduced without giving the passenger a sense of discomfort associated with the operation sound.
The stored power control means starts discharging by the equalization circuit before the predicted parking time, and when the stored power is larger than the target stored power when the electric vehicle is actually parked, Alternatively, the discharge by the equalization circuit may be continued.

  The electric vehicle further includes a power generator and power generation control means for controlling the output of the power generator, and the power storage device can be charged with the power generated by the power generator. The allowable upper limit value of the power storage amount of the power storage device may be reduced according to the predicted parking time, and the power generation control unit may limit the output of the generator according to the decrease of the allowable upper limit value. . Thereby, when the allowable upper limit value of the power generation amount of the power storage device is reduced according to the predicted parking time, the output of the generator is limited. Therefore, it is possible to prevent excessive power generation by the generator according to the predicted parking time.

  The generator is a fuel cell, and the stored power control means sets a reduction condition of the generated power of the fuel cell that causes deterioration of the fuel cell, and reduces the allowable upper limit value of the stored power amount of the power storage device. If the lowering condition is satisfied when the upper limit value is satisfied, the lowering of the allowable upper limit value may be stopped. As a result, when there is a decrease in generated power that causes deterioration of the fuel cell, the output limitation of the fuel cell is stopped due to the decrease in the allowable upper limit value of the storage amount, and the decrease in the output of the fuel cell is alleviated. It becomes possible to prevent deterioration.

  The power storage power control means stores a normal travel allowable lower limit value, which is an allowable lower limit value of the power storage amount of the power storage device during the normal travel, during normal travel without discharging according to the predicted parking time. It is a target value for the amount of electricity stored in the electricity storage device when the electric vehicle is parked, during parking preparation for controlling the amount of electricity stored so that the amount of electricity stored in the device does not fall below and discharging according to the predicted parking time. A target power storage amount is set during parking, and the power storage amount is controlled so that the target power storage amount during parking and the power storage amount of the power storage device are equal at the time of parking. It may be set higher than the hourly allowable lower limit value. Thus, for example, if the lower limit value of the storage amount range in which the fuel cell is less likely to deteriorate is set as the allowable lower limit value during normal travel, the stored power amount of the power storage device during parking of the electric vehicle is set to be lower than the allowable lower limit value during normal travel. Can be high. As a result, even if the power storage device spontaneously discharges, it is possible to reduce the possibility of falling below the allowable lower limit during normal driving. Further, along with this, it is possible to store sufficient power in the power storage device, so that the next start-up of the electric vehicle can be performed reliably.

  According to the present invention, according to the predicted parking time, the stored power of the power storage device is discharged by the discharge resistance of the equalization circuit to reduce the stored power of the power storage device. Since the discharge due to the discharge resistor does not accompany the operation sound, the stored power of the power storage device can be reduced without giving the passenger a sense of discomfort associated with the operation sound.

1 is a schematic configuration diagram of an electric vehicle according to a first embodiment of the present invention. It is a schematic block diagram regarding a part of battery unit contained in the said electric vehicle. It is a top view which shows schematic arrangement | positioning about a part of said battery unit. It is a front view which shows schematic arrangement | positioning about a part of said battery unit. 4 is a flowchart for controlling the power generated by the fuel cell and the amount of electricity stored in the battery in the first embodiment. It is a figure which shows an example of the relationship between the electric power (load required electric power) which the load of the whole electric vehicle requires, and the electric power (FC required electric power) which a fuel cell should generate | occur | produce. It is a figure which shows an example of the relationship between the electrical storage amount of a battery, and the correction amount of FC request | requirement electric power. It is a flowchart which shows the specific process of the parking prediction control in 1st Embodiment. It is a flowchart which shows the specific enemy process of parking preparation necessity judgment in 1st Embodiment. It is a time chart which shows an example of the relationship between the amount of electrical storage in 1st Embodiment, the distance between the present position and destination of an electric vehicle, and the operation | movement of an equalization circuit. It is a flowchart which controls the electric power generated of a fuel cell and the electrical storage amount of a battery in 2nd Embodiment. It is a figure which shows an example of the relationship between the ratio which shows the position of the actual electrical storage amount in the range which the electrical storage amount of a battery can take, and the correction amount of FC request | requirement electric power. It is a flowchart which shows the specific process of the parking prediction control in 2nd Embodiment. It is a flowchart which shows the specific process of parking preparation necessity determination in 2nd Embodiment. It is a figure which shows an example, such as the relationship between the distance from the present position of an electric vehicle to the destination, and the necessity of parking preparation. It is a figure which shows an example, such as the relationship between the continuation time of the state whose vehicle speed is below a predetermined threshold value, and the necessity of parking preparation. Time chart showing an example of the relationship between the amount of battery storage, the distance between the current position of the electric vehicle and the destination, the vehicle speed of the electric vehicle, the FC target power, and the operation of the equalization circuit in the second embodiment It is. It is a figure which shows an example of distribution of the frequency of the electrical storage amount at the time of driving | running | working of an electric vehicle, and parking at the time of performing control of the electrical storage amount of the battery which concerns on 2nd Embodiment.

A. First Embodiment 1. FIG. Configuration of Electric Vehicle 10 (1) Overall Configuration FIG. 1 is a circuit diagram of an electric vehicle 10 according to the first embodiment of the present invention. The electric vehicle 10 includes an electric power system 12 and a motor unit 14. The power system 12 is referred to as an FC unit 16, a battery unit 18, a power distributor 20, a low voltage unit 22, and an integrated control unit 24 {hereinafter referred to as “integrated ECU 24” (ECU: Electric Control Unit). }.

  The motor unit 14 generates a travel driving force of the electric vehicle 10 using the travel motor 30 when the electric vehicle 10 is powered, and regenerative power generated by the motor 30 (motor regenerative power Preg) when the electric vehicle 10 is regenerated. ) [W] is supplied to the battery unit 18 and the low voltage unit 22.

  The FC unit 16 supplies electric power (FC generated power Pfc) [W] generated by the fuel cell 40 (hereinafter referred to as “FC40”) to the motor unit 14 when the electric vehicle 10 is powered. During regeneration, the FC generated power Pfc is supplied to the battery unit 18 and the low voltage unit 22.

  The battery unit 18 supplies power (battery output power Pbat) [W] from the power storage device 60 (hereinafter referred to as “battery 60”), which is energy storage, to the motor unit 14 when the electric vehicle 10 is powered. When the electric vehicle 10 is regenerated, the motor regenerative power Preg and the FC generated power Pfc are stored in the battery 60.

  The power distributor 20 distributes power among the motor unit 14, the FC unit 16, the battery unit 18, and the low voltage unit 22. The low voltage unit 22 has an auxiliary machine that operates at a low voltage (for example, 5 V). The integrated ECU 24 controls the motor unit 14, the FC unit 16, the battery unit 18, the power distributor 20, and the low voltage unit 22. Details will be described later.

(2) Motor unit 14
In addition to the motor 30, the motor unit 14 includes a power drive unit 32 (hereinafter referred to as “PDU32”), a speed reducer 34, a shaft 36, and wheels 38.

  The PDU 32 performs DC / AC conversion between the output current (FC output current Ifc) [A] from the FC 40 and the output current (battery output current Ibat) [A] from the battery 60 when the electric vehicle 10 is powered. 30 is supplied to the motor 30 as a current for driving the motor 30 (motor driving current Imd) [A]. The rotation of the motor 30 accompanying the supply of the motor drive current Imd is transmitted to the wheel 38 through the speed reducer 34 and the shaft 36.

  In addition, the PDU 32 performs AC / DC conversion of the regenerative current (motor regenerative current Imr) [A] from the motor 30 when the electric vehicle 10 is regenerated, and supplies it to the battery unit 18 as the battery charging current Ibc. The battery 60 is charged by the supply of the battery charging current Ibc. The battery charging current Ibc may be supplied to a navigation device 82 or a low voltage battery 84 described later of the low voltage unit 22.

  In the first embodiment, the operations of the motor 30 and the PDU 32 are controlled by the integrated ECU 24. Instead, a motor ECU that controls the motor unit 14 may be provided and controlled by the motor ECU.

(3) FC unit 16
The FC unit 16 includes, in addition to the FC 40, a hydrogen tank 42, an air compressor 44, a backflow prevention diode 46, a voltage sensor 48, and a current sensor 50.

  The FC 40 has, for example, a stack structure in which cells formed by sandwiching a solid polymer electrolyte membrane between an anode electrode and a cathode electrode from both sides are stacked. A hydrogen tank 42 and an air compressor 44 are connected to the FC 40 by piping. Pressurized hydrogen in the hydrogen tank 42 is supplied to the anode electrode of the FC 40. Further, air is supplied to the cathode electrode of the FC 40 by the air compressor 44. In the first embodiment, the operations of the hydrogen tank 42 and the air compressor 44 are controlled by the integrated ECU 24. Instead, a fuel cell ECU that controls the FC unit 16 may be provided and controlled by the fuel cell ECU. An FC output current Ifc is generated by an electrochemical reaction between hydrogen (fuel gas), which is a reaction gas, and air (oxidant gas) in the FC 40. The FC output current Ifc is supplied to the PDU 32 through the current sensor 50 and the backflow prevention diode 46, for example, when the electric vehicle 10 is powered, and to the battery unit 18 and the low voltage unit 22 during regeneration. The FC output voltage Vfc [V] as a detection value by the voltage sensor 48 and the FC output current Ifc as a detection value by the current sensor 50 are used for operation control of the FC 40 and the like.

(4) Battery unit 18
In addition to the battery 60, the battery unit 18 includes an equalization circuit 62, a battery control unit 64 (hereinafter referred to as “battery ECU 64”), a voltage sensor 66, a fan 68, contactors 70 a and 70 b, and a battery box 72. (FIGS. 3 and 4).

  FIG. 2 is a schematic configuration diagram regarding the battery 60 and the equalization circuit 62 as a part of the battery unit 18. FIG. 3 is a plan view showing a schematic arrangement of a part of the battery unit 18, and FIG. 4 is a front view showing a schematic arrangement of a part of the battery unit 18.

  As the battery 60, for example, a lithium ion secondary battery or a capacitor can be used. In the first embodiment, a lithium ion secondary battery is used. As shown in FIG. 2, the battery 60 includes an assembled battery 74 in which a plurality of unit cells 76 are combined.

  The equalization circuit 62 includes a discharge resistor 78 and a switch 80 connected in parallel to each unit cell 76. The switch 80 is controlled by the battery ECU 64 and the integrated ECU 24.

  The battery ECU 64 monitors the temperature of the battery 60 (battery temperature Tbat) [° C.], the storage amount SOC (state of charge) [%], and the like, and if a temperature abnormality or overcharge of the battery 60 is detected, the contactor 70a , 70b and the switch 80 are closed to protect the battery 60.

  Specifically, for example, when the battery temperature Tbat is out of the normal range, the battery ECU 64 operates the fan 68 to cool or heat the battery 60. The case where the battery 60 is heated is, for example, a case where the outside air is hotter than the battery 60. In addition, when the storage amount SOC of each unit cell 76 is different, the switch 80 corresponding to the unit cell 76 having a larger storage amount SOC is turned on and discharged using the discharge resistor 78, and the voltage of each unit cell 76 (cell Voltage) is equalized, so that the storage amount SOC of each unit cell 76 is equalized. The storage amount SOC of the battery 60 is measured based on the voltage of the battery 60 (battery voltage Vbat) [V] detected by the voltage sensor 66. The voltage sensor 66 can measure not only the battery voltage Vbat as the voltage of the entire battery 60 but also the cell voltage of each unit cell 76.

  As shown in FIGS. 3 and 4, the battery 60 is accommodated in a battery box 72. The equalizing circuit 62 is disposed on the side surface of the battery box 72, the battery ECU 64 is disposed on the upper surface of the battery box 72, and the fan 68 is disposed on the front surface of the battery box 72.

(5) Power distributor 20
The power distributor 20 distributes power among the motor unit 14, the FC unit 16, the battery unit 18, and the low voltage unit 22.

  For example, the power distributor 20 includes a DC / DC converter (not shown) connected in series between the motor unit 14, the battery unit 18 and the low voltage unit 22, and connected in parallel with the FC unit 16. Have. The DC / DC converter is a so-called chopper step-up / step-down DC / DC converter, and when the electric vehicle 10 is powered, the primary side voltage (primary voltage V1) [V] of the DC / DC converter is boosted. The secondary side voltage (secondary voltage V2) [V] of the DC / DC converter is stepped down and supplied to the primary side when the electric vehicle 10 is regenerated. That is, the regenerative voltage (motor regenerative voltage Vreg) [V] generated by the motor 30 or the secondary voltage V2 that is the FC output voltage Vfc of the FC 40 is converted into a low voltage by the DC / DC converter, and the battery 60 is used. To charge.

  As the configuration of the power distributor 20, for example, those described in JP 2006-073506 A and JP 2008-091319 A can be used.

(6) Low voltage unit 22
As shown in FIG. 1, the low voltage unit 22 includes a downverter 81, a navigation device 82, a low voltage battery 84, a low voltage battery control unit 86 (hereinafter referred to as “low voltage battery ECU 86”), and a contactor. 88. The low voltage unit 22 may include auxiliary devices other than the navigation device 82, for example, a light, a power window, a wiper motor, and an audio device.

  The downverter 81 steps down the output voltage of the motor unit 14, the FC unit 16, or the battery unit 18 and applies it to the navigation device 82 and the low voltage battery 84.

  The navigation device 82 has a GPS antenna and a database of map information, and can detect the current position of the electric vehicle 10. In addition, the navigation device 82 can input the destination of the electric vehicle 10 and can wirelessly communicate with an external information center, obtains traffic information from the information center to the destination, and the like. It is possible to determine an expected time or an expected arrival time for arrival.

  The low voltage battery 84 has a lower voltage (for example, 5 V) than the battery 60 for driving the motor 30. The low voltage battery ECU 86 monitors the voltage or the like of the low voltage battery 84, and when overcharge or abnormality of the low voltage battery 84 is detected, the charge / discharge is limited or stopped by opening the contactor 88, thereby reducing the low voltage battery. 84 is protected.

(7) Integrated ECU 24
The integrated ECU 24 determines the motor unit 14 based on the required power of the motor 30 (motor required power Pmr_req) [W], the required power of the FC unit 16 (air compressor 44, etc.), the required power of auxiliary equipment such as the navigation device 82, and the like. , Each unit such as the FC unit 16, the battery unit 18, the power distributor 20, and the low voltage unit 22 is controlled.

  The integrated ECU 24 has a CPU, ROM, RAM, timer, input / output interfaces such as an A / D converter and a D / A converter, and a DSP (Digital Signal Processor) as necessary. The same applies to the battery ECU 64 and the low voltage battery ECU 86.

  The integrated ECU 24 and the components such as the motor unit 14, the FC unit 16, the battery unit 18, the power distributor 20, and the low voltage unit 22 are connected to each other through a communication line 90 such as a CAN (Controller Area Network) that is an in-vehicle LAN. Has been. The integrated ECU 24 and each unit share input / output information from various switches and various sensors, and each CPU executes various programs by executing programs stored in each ROM with the input / output information from these various switches and various sensors as inputs. Realize the function.

(8) Others As various switches and various sensors for detecting the vehicle state, in addition to the voltage sensors 48 and 66 and the current sensor 50 described above, an ignition switch 100 connected to the communication line 90 (hereinafter referred to as “IGSW100”). , An accelerator sensor 102, a brake sensor 104, a vehicle speed sensor 106, and the like.

2. FIG. 5 is a flowchart for controlling the FC generated power Pfc of the FC 40 and the stored power SOC of the battery 60 in the first embodiment. The process in FIG. 5 is repeated, for example, at a cycle of several milliseconds to several seconds. Further, the integrated ECU 24 mainly controls the FC generated power Pfc in the first embodiment, and the battery ECU 64 and the integrated ECU 24 mainly control the storage amount SOC.

  In step S <b> 1, the integrated ECU 24 calculates electric power (load required electric power Ptotal_req) [W] required by the load of the entire electric vehicle 10 according to the opening degree of an accelerator pedal (not shown) detected by the accelerator sensor 102. In subsequent step S2, the integrated ECU 24 calculates the power (FC required power Pfc_req) [W] to be generated by the FC 40 corresponding to the load required power Ptotal_req.

  FIG. 6 shows an example of the relationship between the load required power Ptotal_req and the FC required power Pfc_req. As shown in FIG. 6, in the present embodiment, the load required power Ptotal_req and the FC required power Pfc_req are in a proportional relationship, and when the load required power Ptotal_req increases, the FC required power Pfc_req also increases.

  In step S3, the charged amount SOC of the battery 60 is detected and notified to the integrated ECU 24 using the voltage sensor 66, the current sensor 50, and the like. The storage amount SOC in the first embodiment can take a value in the range of 0 to 100%, but is usually 0 to 70% so as not to deteriorate the battery 60 or promote deterioration of the battery 60. Control within the range.

  In step S4, the integrated ECU 24 determines the correction amount (correction amount α) [W] of the FC required power Pfc_req based on the storage amount SOC. The correction amount α is added to the FC required power Pfc_req so that the storage amount SOC becomes equal to the target value (target storage amount SOC_tar) [%].

  FIG. 7 shows an example of the relationship between the storage amount SOC and the correction amount α. As shown in FIG. 7, the storage amount SOC and the correction amount α are in a proportional relationship, and the correction amount α decreases as the storage amount SOC increases. When the charged amount SOC is smaller than the target charged amount SOC_tar, the correction amount α is a positive value. When the charged amount SOC is larger than the target charged amount SOC_tar, the corrected amount α is a negative value. By setting the correction amount α in this way, when the storage amount SOC at that time is lower than the target storage amount SOC_tar, the FC generated power Pfc is made larger than the FC required power Pfc_req, and the storage amount is determined by the surplus. The SOC is increased to approach the target storage amount SOC_tar. On the other hand, when the storage amount SOC at that time exceeds the target storage amount SOC_tar, the FC generated power Pfc is made smaller than the FC required power Pfc_req, and the storage amount SOC is reduced due to the shortage to the target storage amount SOC_tar. Get closer.

  In the first embodiment, the target storage amount SOC_tar is variable. Specifically, the target storage amount SOC_tar (the normal storage target storage amount SOC_tar_d) during normal driving (that is, when the electric vehicle 10 is in operation and the parking preparation process described later is not performed), and during parking preparation (That is, when a parking preparation process described later is performed), a target storage amount SOC_tar (parking target storage amount SOC_tar_p) when the electric vehicle 10 is parked is set, and the electric vehicle 10 according to the traveling state of the electric vehicle 10 Thus, the target storage amount SOC_tar_d during normal driving and the target storage amount SOC_tar_p during parking are switched. In the first embodiment, the normal travel target power storage amount SOC_tar_d and the parking target power storage amount SOC_tar_p are both fixed values, and the normal travel target power storage amount SOC_tar_d is, for example, 50%, and the parking target power storage amount SOC_tar_p is For example, 40% is set so that the latter is lower than the former.

  Returning to FIG. 5, in step S5, the integrated ECU 24 calculates a value (FC target power Pfc_tar) [W] reflecting the correction amount α in the FC required power Pfc_req (Pfc_tar = Pfc_req + α). In step S6, the integrated ECU 24 controls the FC unit 16 and the power distributor 20 so that the FC generated power Pfc becomes equal to the FC target power Pfc_tar. For example, the FC 40 target voltage (FC target voltage Vfc_tar) [V] corresponding to the FC target power Pfc_tar is set, and the battery voltage Vbat is set to a DC / DC (not shown) of the power distributor 20 so as to realize the FC target voltage Vfc_tar. Boost with a DC converter.

  In step S7, the integrated ECU 24 executes parking prediction control. The parking prediction control means that when the electric vehicle 10 approaches the destination, the storage amount SOC of the battery 60 is reduced as a preparation when the electric vehicle 10 parks, and the target at the time of parking when the electric vehicle 10 is parked. This control is made equal to SOC_tar_p.

  FIG. 8 is a flowchart showing a specific process of parking prediction control (S7 in FIG. 5). In step S <b> 11, the integrated ECU 24 determines whether or not parking preparation is necessary for determining whether the storage amount SOC of the battery 60 needs to be prepared when the electric vehicle 10 is parked (hereinafter also referred to as “parking preparation”).

  FIG. 9 is a flowchart showing specific processing for determining whether parking preparation is necessary. In step S21, the integrated ECU 24 determines whether the select lever of the electric vehicle 10 is in the parking position (P range), whether the side brake is applied, and whether the IGSW 100 is off. If any of the above is satisfied (that is, the P range is selected by the select lever, the side brake is operating, or the IGSW 100 is off) (S21: YES), in step S22, the integrated ECU 24 It is determined that parking preparation is required for the storage amount SOC of the battery 60.

  If none of the above conditions is satisfied in step S21 (S21: NO), in step S23, the integrated ECU 24 determines whether or not the electric vehicle 10 is approaching the destination. Specifically, the integrated ECU 24 determines whether or not the distance D [m] from the current position of the electric vehicle 10 to the destination is equal to or less than a threshold value TH_D [m]. When the distance D is equal to or less than the threshold value TH_D (S23: YES), it can be determined that the electric vehicle 10 is approaching the destination (coming to the vicinity of the destination). In this case, in step S22, the integrated ECU 24 determines that parking preparation is required. If the distance D is greater than the threshold TH_D (S23: NO), it can be determined that the electric vehicle 10 has not yet approached the destination (has not yet reached the destination). Therefore, in step S24, the integrated ECU 24 determines that parking preparation is not required.

  Returning to FIG. 8, in step S <b> 12, the integrated ECU 24 confirms the result of the parking preparation necessity determination (S <b> 11). When parking preparation is required (S12: YES), the process proceeds to step S13, and parking preparation processing (S13, S14) is performed. When parking preparation is not required (S12: NO), the current parking prediction control is terminated and the process returns to FIG.

  In step S13, the integrated ECU 24 determines whether or not the charged amount SOC of the battery 60 detected in step S3 in FIG. 5 is larger than the parking target charged amount SOC_tar_p. As described above, the parking target storage amount SOC_tar_p is a target value of the storage amount SOC when the electric vehicle 10 is parked, and is set to a fixed value (for example, 40%) in the first embodiment.

  If the charged amount SOC is larger than the parking target charge amount SOC_tar_p (S13: YES), in step S14, the integrated ECU 24 operates the equalization circuit 62 to discharge the battery 60. More specifically, each switch 80 is turned on, and each unit cell 76 is discharged by each discharge resistor 78. Thereby, the amount of stored electricity SOC can be reduced and brought close to the target amount of electricity stored during parking SOC_tar_p. When the charged amount SOC is equal to or less than the parking target charge amount SCO_tar_p (S13: NO), it is not necessary to reduce the charged amount SOC, so the process of FIG. 8 is performed without performing discharge (S14) by the equalization circuit 62. Exit.

  FIG. 10 is a time chart showing an example of the relationship between the storage amount SOC in the first embodiment, the distance D between the current position of the electric vehicle 10 and the destination, and the operation of the equalization circuit 62. Yes. In FIG. 10, until the time t1, none of the selection of the P range, the operation of the side brake, and the OFF of the IGSW 100 are applicable, and the distance D is larger than the threshold value TH_D. For this reason, the operation | movement of the equalization circuit 62 accompanying parking prediction control (S7 of FIG. 5) is not performed. However, the equalization process for equalizing the voltages of the unit cells 76 is appropriately performed by the battery ECU 64 controlling the equalization circuit 62.

  When the distance D becomes equal to the threshold value TH_D at time t1, the integrated ECU 24 determines that parking preparation is required. Further, at the time point t1, the storage amount SOC is higher than the parking target storage amount SOC_tar_p. Therefore, the integrated ECU 24 turns on the equalization circuit 62 and starts discharging the battery 60 by the equalization circuit 62. In this discharge, all the switches 80 are turned on, and all the discharge resistors 78 are operated. Alternatively, a switch 80 to be turned on may be selected as necessary, and only some of the discharge resistors 78 may be activated.

  At time t2, the distance D becomes zero, and the electric vehicle 10 reaches the destination. At this time, the charged amount SOC of the battery 60 is higher than the parking target charge amount SOC_tar_p (SOC> SOC_tar_p). For this reason, the integrated ECU 24 continues the discharge by the equalization circuit 62.

  When the charged amount SOC becomes equal to the parking target charged amount SOC_tar_p at time t3 (SOC = SOC_tar_p), the integrated ECU 24 ends the discharge by the equalization circuit 62.

3. Advantages of the First Embodiment As described above, according to the first embodiment, when the parking preparation is required according to the predicted parking time, that is, when it is determined that parking preparation is required, the storage amount SOC of the battery 60 is equalized. The discharge resistance 78 of the battery 60 discharges the battery 60 to reduce the stored amount SOC. Since the discharge due to the discharge resistor 78 does not accompany the operation sound, the charged amount SOC of the battery 60 can be reduced without giving the passenger an uncomfortable feeling associated with the operation sound. In addition, since the preparation for parking can be started before the electric vehicle 10 is actually parked, it is more efficient than the case where the storage amount SOC of the battery 60 is reduced for the first time after the electric vehicle 10 is actually parked.

B. Second Embodiment 1. FIG. Configuration of the second embodiment (difference in configuration from the first embodiment)
The hardware configuration of the second embodiment is the same as that of the first embodiment, and the difference between the two embodiments is in the processing (software). For this reason, below, it demonstrates using the same referential mark as the component of 1st Embodiment.

2. FIG. 11 is a flowchart for controlling the FC power generation power Pfc of the FC 40 and the power storage amount SOC of the battery 60 in the second embodiment. The process of FIG. 11 is repeated with a period of several milliseconds to several seconds, for example. The integrated ECU 24 mainly controls the FC generated power Pfc in the second embodiment, and the battery ECU 64 and the integrated ECU 24 mainly control the storage amount SOC.

  Steps S31 to S33 are the same as steps S1 to S3 in FIG.

In step S34, the integrated ECU 24 calculates the ratio R using the storage amount SOC, the allowable upper limit value (upper limit SOC_up) [%] of the storage amount SOC, and the allowable lower limit value (lower limit value SOC_low) of the storage amount SOC. To do. The ratio R is obtained by the following formula (1).
R = (SOC-SOC_low) / (SOC_up-SOC_low) (1)

  As can be seen from the above formula (1), the ratio R indicates the position of the charged amount SOC in the range that the charged amount SOC can take (range from the lower limit value SOC_low to the upper limit value SOC_up). In other words, the ratio R indicates whether the charged amount SOC is closer to the lower limit value SOC_low or the upper limit value SOC_up. For example, when the ratio R is close to 1, the storage amount SOC is close to the upper limit value SOC_up, and when the ratio R is close to 0, the storage amount SOC is close to the lower limit value SOC_low. For this reason, if the target value of the ratio R is set and the ratio R is controlled to be equal to the target value, even if the lower limit value SOC_low and the upper limit value SOC_up are changed, the charged amount SOC follows the change. Can do.

  In step S35, the integrated ECU 24 determines the correction amount (correction amount β) [W] of the FC required power Pfc_req based on the ratio R. The correction amount β has the same purpose as the correction amount α of the first embodiment, and is added to the FC required power Pfc_req so that the ratio R becomes equal to the target value (target ratio R_tar).

  FIG. 12 shows an example of the relationship between the ratio R and the correction amount β. As shown in FIG. 12, the ratio R and the correction amount β are in a proportional relationship, and when the ratio R increases, the correction amount β decreases. When the ratio R is smaller than the target ratio R_tar, the correction amount β is a positive value. When the ratio R is larger than the target ratio R_tar, the correction amount β is a negative value. By setting the correction amount β in this way, when the ratio R at that time is lower than the target ratio R_tar, the FC generated power Pfc is made larger than the FC required power Pfc, and the storage amount SOC is set by the surplus. By increasing the ratio, the ratio R is increased to approach the target ratio R_tar. On the other hand, when the ratio R at that time exceeds the target ratio R_tar, the ratio R is decreased by reducing the FC generated power Pfc to be smaller than the FC required power Pfc_req and reducing the storage amount SOC due to the shortage. It approaches the target ratio R_tar.

  In the second embodiment, the target ratio R_tar is a fixed value (for example, 0.5), but may be variable. For example, as in the first embodiment, the target ratio R_tar (the normal driving target ratio R_tar1) during normal driving (that is, when the electric vehicle 10 is in operation and the parking preparation processing is not performed) and the parking preparation are performed. The target ratio R_tar (the target ratio R_tar2 at the time of parking preparation) is set, and the target ratio R_tar1 at the normal driving time and the target at the time of parking preparation are set according to the driving state of the electric vehicle 10 The ratio R_tar2 can be switched.

  Returning to FIG. 11, in step S36, the integrated ECU 24 calculates a value (FC target power Pfc_tar2) [W] reflecting the correction amount β in the FC required power Pfc_req (Pfc_tar2 = Pfc_req + β). In step S37, the integrated ECU 24 controls the FC unit 16 and the power distributor 20 so that the FC generated power Pfc becomes equal to the FC target power Pfc_tar2. For example, the FC target voltage Vfc_tar corresponding to the FC target power Pfc_tar2 is set, and the battery voltage Vbat is boosted by a DC / DC converter (not shown) of the power distributor 20 so as to realize the FC target voltage Vfc_tar.

  In step S37, the integrated ECU 24 executes parking prediction control. The parking prediction control of the second embodiment is similar to the parking prediction control of the first embodiment. When the electric vehicle 10 approaches the destination, the storage amount of the battery 60 is prepared as a preparation when the electric vehicle 10 is parked. In this control, the SOC is decreased and equal to the parking target storage amount SOC_tar_p when the electric vehicle 10 is parked.

  FIG. 13 is a flowchart showing specific processing of parking prediction control in the second embodiment. In step S <b> 41, the integrated ECU 24 determines whether or not parking preparation is necessary for determining whether or not preparation (parking preparation) for the electric vehicle 10 to park is required for the storage amount SOC of the battery 60.

  FIG. 14 is a flowchart showing specific processing for determining whether or not the parking preparation is necessary. In step S51, the integrated ECU 24 determines whether the select lever of the electric vehicle 10 is in the parking position (P range), whether the side brake is applied, and whether the IGSW 100 is off. If any of the above is satisfied (that is, the P range is selected by the select lever, the side brake is operating, or the IGSW 100 is OFF) (S51: YES), in step S52, the integrated ECU 24 It is determined that parking preparation is required for the storage amount SOC of the battery 60.

  If none of the above conditions is satisfied in step 51 (S51: NO), in step S53, the integrated ECU 24 determines whether or not the electric vehicle 10 is approaching the destination. Specifically, as in step S23 of FIG. 9, the integrated ECU 24 determines whether or not the distance D from the current position of the electric vehicle 10 to the destination is less than or equal to the threshold value TH_D, and the distance D is less than or equal to the threshold value TH_D. (S53: YES), the integrated ECU 24 determines that parking preparation is required. When the distance D is greater than the threshold TH_D (S53: NO), the process proceeds to step S54.

  FIG. 15 is a diagram illustrating an example of the relationship between the distance D from the current position of the electric vehicle 10 to the destination and the necessity of parking preparation. As shown in FIG. 15, when the distance D is equal to or less than the threshold value TH_D, it is determined that parking preparation is required, and when the distance D exceeds the threshold value TH_D, it is determined that parking preparation is not required.

  FIG. 15 also shows an example of the relationship between the target power storage amount SOC_tar_d during normal travel, the target power storage amount SOC_tar_p during parking, the upper limit SOC_up, and the lower limit SOC_low. As described above, the normal running target storage amount SOC_tar_d is a target value of the storage amount SOC used during normal driving of the electric vehicle 10, and the parking target storage amount SOC_tar_p is the target of the storage amount SOC used during parking preparation. Value. The upper limit SOC_up and the lower limit SOC_low increase with an increase in the distance D when the distance D is between zero and the threshold TH_D, and are constant when the distance D exceeds the threshold TH_D. The normal travel target power storage amount SOC_tar_d, the parking target power storage amount SOC_tar_p, the upper limit SOC_up, and the lower limit SOC_low will be described in relation to step S45 of FIG.

  Returning to FIG. 14, in step S <b> 54, it is determined whether or not the electric vehicle 10 is traveling slowly. Specifically, the duration T [second] in a state where the vehicle speed V [km / h] of the electric vehicle 10 is equal to or less than the threshold value TH_V [km / h] (for example, 20 km / h) is the threshold value TH_T (for example, 10 seconds). Judge whether it has continued for tens of seconds). At this time, if the travel path of the electric vehicle 10 is congested (especially when it is congested on a highway), it may not be included during slow driving. The determination of the traffic jam can be performed by acquiring the traffic jam information from the information center via the navigation device 82, for example. Or you may acquire by the communication between vehicles between surrounding vehicles, and the road-vehicle communication between optical beacons. In addition, the determination of the expressway can be performed based on the map information that the navigation device 82 has. Furthermore, in order to exclude the signal waiting time from the duration T, it is possible to exclude the time when the vehicle speed V is zero or a value close thereto.

  If the electric vehicle 10 is not traveling slowly (S54: NO), in step S55, the integrated ECU 24 determines that preparation for parking is not required. When the electric vehicle 10 is traveling slowly (S54: YES), in step S52, the integrated ECU 24 determines that parking preparation is required.

  FIG. 16 is a diagram illustrating an example of a relationship between a duration T in a state where the vehicle speed V is equal to or lower than a threshold value TH_V and necessity of parking preparation. As shown in FIG. 16, when the duration T is equal to or less than the threshold TH_T, it is determined that parking preparation is not required, and when the duration T exceeds the threshold TH_T, it is determined that parking preparation is required.

  FIG. 16 also shows an example of the relationship between the target running power storage amount SOC_tar_d, the parking target storage power SOC_tar_p, the upper limit SOC_up, and the lower limit SOC_low. The normal driving target storage amount SOC_tar_d, the parking target storage amount SOC_tar_p, the upper limit SOC_up, and the lower limit SOC_low are the same as those in FIG. 15 and will also be described in relation to step S45 of FIG.

  In addition, as described above, the following effects are obtained by determining whether the vehicle is traveling slowly even though the destination registered in the navigation device 82 is not approached (S53: NO). be able to. For example, when only the home is entered as the destination in the navigation device 82, when going to the nearest large supermarket, moving in the parking lot of the supermarket will reduce the stored energy SOC early when slow driving continues. Can be made.

  Returning to FIG. 13, in step S <b> 42, the integrated ECU 24 checks the result of the parking preparation necessity determination (S <b> 41). When parking preparation is required (S42: YES), the process proceeds to step S43, and parking preparation processing (S43 to S48) is performed. When parking preparation is not required (S42: NO), this parking prediction control is complete | finished and it returns to FIG.

  In step S43, the integrated ECU 24 determines whether or not the storage amount SOC of the battery 60 detected in step S33 of FIG. 11 is greater than the parking target storage amount SOC_tar_p. The parking target storage amount SOC_tar_p is a target value of the storage amount SOC when the electric vehicle 10 is parked, and is set to a fixed value (for example, 40%) in the second embodiment.

  When the charged amount SOC is larger than the parking target charge amount SOC_tar_p (S43: YES), in step S44, the integrated ECU 24 operates the equalizing circuit 62 to discharge the battery 60. Thereby, the amount of stored electricity SOC can be reduced and brought close to the target amount of electricity stored during parking SOC_tar_p. When the charged amount SOC is equal to or less than the parking target charged amount SOC_tar_p (S43: NO), there is no need to reduce the charged amount SOC, so the process proceeds to step S45 without discharging (S44) by the equalization circuit 62.

  In step S45, the integrated ECU 24 performs an SOC upper / lower limit value reduction process (hereinafter also referred to as an “upper / lower limit value reduction process”). In the upper and lower limit value reduction processing, the allowable upper limit value (upper limit value SOC_up) and the allowable lower limit value (lower limit value SOC_low) of the charged amount SOC are set, the distance D from the current position of the electric vehicle 10 to the destination, or the vehicle speed V is the threshold value TH_V. This is a process of lowering according to the duration T of the state as follows.

  Specifically, when it is determined in step S53 of FIG. 14 that the electric vehicle 10 is approaching the destination (S53: YES), the upper limit SOC_up and the lower limit SOC_low are set according to the distance D used for the determination. Reduce. The relationship between the distance D and the upper limit SOC_up and the lower limit SOC_low is, for example, that shown in FIG. When the upper limit value SOC_up and the lower limit value SOC_low are determined, the normal running target storage amount SOC_tar_d is set using the relationship shown in FIG. Furthermore, parking target storage amount SOC_tar_p is set higher than upper limit SOC_up during normal travel.

  Further, when it is determined in step S54 of FIG. 14 that the electric vehicle 10 is traveling slowly (S54: YES), the upper limit SOC_up and the lower limit SOC_low are decreased according to the duration T used for the determination. The relationship between the duration T, the upper limit SOC_up and the lower limit SOC_low is, for example, that shown in FIG. When the upper limit SOC_up and the lower limit SOC_low are determined, the normal running target storage amount SOC_tar_d is set using the relationship shown in FIG. Furthermore, parking target storage amount SOC_tar_p is set higher than upper limit SOC_up during normal travel.

  In FIG. 15 and FIG. 16, the target storage amount SOC_tar_p at the time of parking is present regardless of whether parking preparation is present or not, considering the case of the P range or the like (S51: YES).

  Returning to FIG. 13, in step S46, the integrated ECU 24 refers to the FC target power Pfc_tar2 determined in the current calculation cycle {hereinafter referred to as “FC target power Pfc_tar2 (current)”. } And FC target power Pfc_tar2 determined in the previous calculation cycle {hereinafter referred to as “FC target power Pfc_tar2 (previous)”. } (Difference ΔPfc_tar2) [W] is calculated.

  In step S47, the integrated ECU 24 determines whether or not the absolute value of the difference ΔPfc_tar2 is greater than the threshold value TH_ΔPfc2. The threshold value TH_ΔPfc2 is set to a value that causes or promotes the deterioration of the FC 40 when the absolute value of the difference ΔPfc_tar2 becomes a value larger than that. When the absolute value is larger than the threshold value TH_ΔPfc2 (S47: YES), in step S48, the integrated ECU 24 cancels the lowering of the upper limit value SOC_up and the lower limit value SOC_low performed in step S45, and sets the upper limit value SOC_up and the lower limit value SOC_low. The value is returned to the initial value (value before the SOC upper / lower limit value lowering process is performed). Thereby, it becomes possible to prevent the deterioration of the FC 40 or the promotion thereof. When the absolute value is equal to or smaller than the threshold value TH_ΔPfc2 (S47: NO), the current process of FIG. 13 is terminated without passing through step S48.

  In FIG. 17, the storage amount SOC in the second embodiment, the distance D between the current position and the destination of the electric vehicle 10, the vehicle speed V of the electric vehicle 10, the FC target power Pfc_tar2, and the equalization circuit 62 The time chart which shows an example of the relationship with operation | movement is shown. In FIG. 17, until the time t11, none of the conditions that require parking preparation are satisfied. In other words, none of the selection of the P range, the operation of the side brake, and the turning off of the IGSW 100 are applicable (S51: NO), the destination is not approached (S53: NO), and the vehicle is not traveling slowly (S54: NO). For this reason, the operation | movement of the equalization circuit 62 accompanying parking prediction control is not performed. However, the equalization process for equalizing the voltages of the unit cells 76 is appropriately performed by the battery ECU 64 controlling the equalization circuit 62.

  When the distance D becomes equal to the threshold value TH_D at time t11, the integrated ECU 24 determines that parking preparation is required. Further, at the time t11, the charged amount SOC is higher than the parking target charge amount SOC_tar_p. Therefore, the integrated ECU 24 turns on the equalization circuit 62 and starts discharging the battery 60 by the equalization circuit 62. In this discharge, all the switches 80 are turned on, and all the discharge resistors 78 are operated. Alternatively, a switch 80 to be turned on may be selected as necessary, and only some of the discharge resistors 78 may be activated.

  At time t12, the vehicle speed V becomes equal to or less than the threshold value TH_V, but since the distance D is already equal to or less than the threshold value TH_D, the operation of the equalization circuit 62 is not affected, and the equalization circuit 62 remains on.

  When the FC target output Pfc_tar2 starts to rapidly decrease at time t13 and the absolute value of the difference ΔPfc_tar2 exceeds the threshold value TH_ΔPfc2, the integrated ECU 24 stops decreasing the upper limit SOC_up and the lower limit SOC_low and resets both values. . As a result, the upper limit SOC_up of the battery 60 increases, and the battery 60 can charge more FC generated power Pfc. In addition, when the upper limit SOC_up and the lower limit SOC_low are reset in a state in which the storage amount SOC does not change, the ratio R decreases. As a result, the correction amount β increases and the FC target output Pfc_tar2 decreases gradually.

  When the FC target output Pfc_tar2 gradually decreases at time t14 and the absolute value of the difference ΔPfc_tar2 becomes equal to or smaller than the threshold value TH_ΔPfc2, the integrated ECU 24 resumes lowering of the upper limit value SOC_up and the lower limit value SOC_low, and the normal operation target storage amount SOC_tar_d The decline will resume.

  At time t15, the distance D becomes zero, and the electric vehicle 10 reaches the destination. At this time, the charged amount SOC of the battery 60 is higher than the parking target charge amount SOC_tar_p (SOC> SOC_tar_p). For this reason, the integrated ECU 24 continues the discharge by the equalization circuit 62.

  When the charged amount SOC becomes equal to the parking target charged amount SOC_tar_p at time t16 (SOC = SOC_tar_p), the integrated ECU 24 ends the discharge by the equalization circuit 62.

  FIG. 18 shows an example of the distribution of the frequency [%] of the charged amount SOC when the electric vehicle 10 is traveling and parked when the charged amount SOC is controlled according to the second embodiment. As shown in FIG. 18, when the storage amount SOC according to the second embodiment is controlled, the storage amount SOC during traveling is distributed centering around 50% that is the target storage amount SOC_tar_d during normal travel, and when parked The amount of stored electricity SOC is distributed around the parking target storage amount SOC_tar_p of 40%. Therefore, when the electric vehicle 10 is parked, the storage amount SOC can be reduced to the parking target storage amount SOC_tar_p.

3. Effects of Second Embodiment As described above, in the second embodiment, the following effects can be obtained in addition to the effects obtained in the first embodiment.

  In the second embodiment, the integrated ECU 24 reduces the upper limit value SOC_up of the storage amount SOC of the battery 60 according to the predicted parking time, that is, when it is determined that parking preparation is required, and reduces the upper limit value SOC_up. Accordingly, the output of FC40 is limited. Thereby, when the upper limit SOC_up is lowered, the output of the FC 40 is limited. Therefore, when it is determined that parking preparation is required, it is possible to prevent excessive power generation by the FC 40.

  In the second embodiment, the integrated ECU 24 sets a threshold value TH_ΔPfc2 related to the difference ΔPfc_tar2 as a decrease condition of the FC generated power Pfc that causes the deterioration of the FC40, and the absolute value of the difference ΔPfc_tar2 is the threshold value TH_ΔPfc2 when the upper limit SOC_up is decreased. When the value exceeds the upper limit SOC_up, the lowering of the upper limit SOC_up is stopped. As a result, when there is a decrease in FC generated power Pfc that causes the FC40 to deteriorate, the FC40 output restriction accompanying the decrease in the upper limit SOC_up is stopped, and the FC40 output decrease is mitigated to prevent the FC40 deterioration. Is possible.

  In the second embodiment, the integrated ECU 24 controls the storage amount SOC so that the storage amount SOC does not fall below the lower limit SOC_low of the storage amount SOC of the battery 60 when parking preparation is not required, and when parking preparation is required. The target storage amount SOC_tar_p at the time of parking is set, and the storage amount SOC is controlled so that the target storage amount SOC_tar_p at the time of parking and the storage amount SOC become equal when the electric vehicle 10 is parked. It is set higher than the lower limit value SOC_low at the time. Thus, for example, if the lower limit value of the range of the stored electricity SOC where the FC 40 is unlikely to deteriorate is set as the lower limit value SOC_low during normal traveling, the stored amount SOC during parking of the electric vehicle 10 is less than the lower limit value SOC_low during normal traveling. Can also be high. As a result, it is possible to reduce the possibility that the battery 60 will naturally fall below the lower limit SOC_low during normal travel even if the battery 60 is naturally discharged. Moreover, since it becomes possible to store sufficient electric power in the battery 60 in connection with this, it becomes possible to perform the next starting of the electric vehicle 10 reliably.

C. Modifications It should be noted that the present invention is not limited to the above-described embodiments, and it is needless to say that various configurations can be adopted based on the contents described in this specification. For example, the following configuration can be adopted.

1. Mounting target and load In each of the above embodiments, the electric power system 12 including the FC 40 and the battery 60 is mounted on the electric vehicle 10, but the present invention is not limited thereto, and may be mounted on another target. For example, you may mount in the vehicle provided with the battery 60 and a solar cell. Or the electric power system 12 can also be used for moving bodies, such as a ship and an aircraft. Alternatively, the power system 12 may be used as a home power system. In this case, it can also be combined with a generator that temporarily generates electric power, such as a wind power generation system or a solar power generation system. Moreover, in each said embodiment, although the motor 30 for driving | running | working etc. was mentioned as a load of the electric power system 12, it can also be set as another load according to the use of the electric power system 12. FIG.

2. Generator In each of the above embodiments, the FC 40 is used as a generator connected to the motor 30 (load) in parallel with the battery 60, but other generators such as a generator combining an engine and an alternator may be used. it can.

3. Discharge In each of the above embodiments, when the parking preparation is required, the integrated ECU 24 controls the discharge of the battery 60 by the equalization circuit 62. However, the present invention is not limited to this, and can be controlled by the battery ECU 64, for example.

4). Storage amount SOC
In each of the above embodiments, the control based on the storage amount SOC [%] is performed, but the control based on the battery voltage Vbat can also be performed. That is, since the storage amount SOC and the battery voltage Vbat have a one-to-one correspondence, it is also possible to replace the storage amount SOC in the above-described control with the battery voltage Vbat.

5. Prediction of parking time (target power storage amount SOC_tar)
In each of the embodiments described above, the normal travel target power storage amount SOC_tar_d and the parking target power storage amount SOC_tar_p are set according to the necessity of parking preparation (two-step determination), and the discharge by the equalization circuit 62 is controlled using these. However, the present invention is not limited to this, and three or more target power storage amounts SOC_tar may be set. For example, three or more target power storage amounts SOC_tar can be set according to the current position of the electric vehicle 10 and the distance D to the destination, and the discharge by the equalization circuit 62 can be controlled using these. Alternatively, it is also possible to set the target storage amount SOC_tar according to the expected time until arrival at the destination or the expected arrival time instead of the distance D.

10. Electric vehicle 24 ... Integrated ECU (Parking prediction means, stored power control means, power generation control means)
40 ... FC (generator) 60 ... Battery (power storage device)
62 ... Equalization circuit 74 ... Battery pack 76 ... Unit cell 78 ... Discharge resistance Pfc ... FC generated power SOC ... Storage amount SOC_low ... Lower limit SOC_up ... Upper limit

Claims (4)

An electric vehicle driven by electric power from a power storage device having an assembled battery in which a plurality of unit cells are combined,
An equalization circuit that discharges at least one stored power among the plurality of unit cells by a discharge resistor connected in parallel to each of the plurality of unit cells, and equalizes the amount of power stored in the plurality of unit cells;
A parking time prediction means for predicting a parking time of the electric vehicle;
A storage power control means for discharging the stored power of the power storage device by the equalization circuit and reducing the stored power of the power storage device to a target stored power according to the parking time predicted by the parking time prediction means. ,
The stored power control means starts discharging by the equalization circuit before the predicted parking time, and when the stored power is larger than the target stored power when the electric vehicle is actually parked, The electric vehicle is characterized in that the discharge by the equalization circuit is continued . The electric vehicle according to claim 1,
Furthermore, a generator, and a power generation control means for controlling the output of the generator,
The power generated by the generator can be charged to the power storage device,
The storage power control means reduces an allowable upper limit value of the storage amount of the power storage device according to the predicted parking time,
The power generation control means limits the output of the generator according to a decrease in the allowable upper limit value. An electric vehicle driven by electric power from a power storage device having an assembled battery in which a plurality of unit cells are combined,
An equalization circuit that discharges at least one stored power among the plurality of unit cells by a discharge resistor connected in parallel to each of the plurality of unit cells, and equalizes the amount of power stored in the plurality of unit cells;
A parking time prediction means for predicting a parking time of the electric vehicle;
A storage power control means for discharging the stored power of the power storage device by the equalization circuit and reducing the stored power of the power storage device according to the parking time predicted by the parking time prediction means;
A generator,
Power generation control means for controlling the output of the generator;
With
The power generated by the generator can be charged to the power storage device,
The storage power control means reduces an allowable upper limit value of the storage amount of the power storage device according to the predicted parking time,
The power generation control means limits the output of the generator according to a decrease in the allowable upper limit value,
The generator is a fuel cell;
The stored power control means includes
Set a condition for reducing the power generated by the fuel cell, which causes deterioration of the fuel cell,
The electric vehicle, wherein when the reduction condition is satisfied while the allowable upper limit value of the storage amount of the power storage device is being reduced, the reduction of the allowable upper limit value is stopped. The electric vehicle according to any one of claims 1 to 3,
The stored power control means includes
During normal travel without discharging according to the predicted parking time, the power storage amount of the power storage device does not fall below the allowable lower limit value during normal travel that is the allowable lower limit value of the power storage amount of the power storage device during the normal travel. Control the amount of electricity stored,
At the time of parking preparation for performing discharge according to the predicted parking time, a parking target power storage amount that is a target value of the power storage amount of the power storage device at the time of parking of the electric vehicle is set. Controlling the power storage amount so that the target power storage amount and the power storage amount of the power storage device are equal,
The parked target power storage amount is set to be higher than the normal traveling allowable lower limit value.

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