JP2018034744A - Hybrid vehicle system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hybrid vehicle system with a battery overheat suppressed even in the case of a charge-discharge load of a secondary battery being large when a heater is turned on under an extreme low temperature condition.SOLUTION: A hybrid vehicle system 10 includes: an air-conditioner-battery cooling part 60 for supplying a cabin air-conditioning unit 62 and a secondary battery cooling unit 64 with a common coolant; and a control device 40 for controlling charge-discharge power of a secondary battery 20 in accordance with a battery temperature. In the case of satisfying three conditions, i.e., an external temperature is equal to or lower than a given temperature, a cabin air-conditioning is a heating mode, and a battery load of the secondary battery is equal to or higher than a given power value, the control device 40 shifts limitation of charge-discharge power toward a low temperature side of the battery temperature in comparison with the case of dissatisfying at least one of the three conditions.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a hybrid vehicle system, and more particularly, to a hybrid vehicle system that uses a refrigerant used in a vehicle interior air conditioning unit as a refrigerant used in a secondary battery cooling unit.

  The secondary battery mounted on the hybrid vehicle generates heat due to charging / discharging and needs to be cooled. If the refrigerant used for vehicle interior air conditioning of the vehicle and the refrigerant used for cooling the secondary battery are used in combination, the mountability of the secondary battery cooling unit on the vehicle is improved.

  Patent Document 1 has a refrigerant circulation circuit that uses a common refrigerant for the indoor air-conditioning unit and the battery cooling unit, and is lower than the charge / discharge control start temperature Tb1 of the battery and higher than the normal operating temperature range upper limit Tb3 of the battery. It is stated that the battery cooling priority upper limit temperature Tb2 is set in the high temperature range. Here, when the battery temperature is equal to or higher than Tb2, the supply of the refrigerant to the indoor air conditioning unit is stopped, and the entire amount of the refrigerant is sent to the battery cooling unit.

  Patent Document 2 describes a temperature control device for an electric vehicle that includes a battery cooling water circuit and a refrigeration cycle circuit, and performs heating / cooling of a vehicle interior and warming up / cooling of a secondary battery. Here, it is pointed out that especially in the summer and winter, a large amount of air-conditioning energy is required for cooling and heating the passenger compartment, and the cruising distance of the electric vehicle decreases. Therefore, at the start of operation in summer and winter, the refrigeration cycle is driven by an external power supply, the generated cold / heat is transferred to the battery cooling water circuit, and the secondary battery is cooled / heated to accumulate heat energy. It is disclosed that it is made into a (heat capacity element) and used for subsequent cooling and heating.

As a technique related to the present disclosure, Patent Document 3 discloses that the discharge power limit value W _OUT and the charge power limit value W _IN of a secondary battery mounted on a vehicle are deteriorated in charge efficiency when charging compared to when discharging. It is pointed out that temperature rise is likely to occur. Therefore, the limit start temperature of W _IN when the battery temperature is a high temperature, than the limit start temperature of W _OUT discloses that starts at a low temperature side.

JP 2012-030663 A JP 2012-232730 A Japanese Patent Laid-Open No. 2007-221885

  By using a heat pump that utilizes a cycle of refrigerant compression / condensation / expansion / evaporation, the refrigerant used for the vehicle interior air conditioning unit can be used in combination as the refrigerant used for the secondary battery cooling unit. When a room is heated using a heat pump, heat is absorbed from the outside air, and a high-pressure and high-temperature gas is further raised by compression to radiate heat to the room air. Here, when the outside air temperature is an extremely low temperature of, for example, −10 ° C. or less, heat is taken away from the gas that has been made high pressure and high temperature by compression, and the cooling effect by the expansion valve in the subsequent secondary battery cooling is reduced. Under this circumstance, if the battery load for charging / discharging the secondary battery is large, the battery cell having a large internal resistance may be abnormally overheated. Therefore, there is a demand for a hybrid vehicle system that can suppress battery overheating even when the battery load of the secondary battery is large during heating at extremely low temperatures.

  A hybrid vehicle system according to the present disclosure includes an air conditioning / battery cooling unit that supplies a common refrigerant to a vehicle interior air conditioning unit and a secondary battery cooling unit, an outside air temperature detecting unit that detects an outside air temperature of the vehicle, A battery load detecting unit for detecting a battery load due to charging / discharging of the battery, a battery temperature detecting unit for detecting a battery temperature of the secondary battery, and a control device for limiting charge / discharge power of the secondary battery according to the battery temperature; The control device has three conditions: the outside air temperature is a low temperature equal to or lower than a predetermined temperature, the vehicle interior air conditioning is in a heating mode, and the battery load of the secondary battery is equal to or higher than a predetermined power value. When satisfy | filling, compared with when not satisfy | filling at least 1 of three conditions, the restriction | limiting of charging / discharging electric power is shifted to the low temperature side of battery temperature.

  According to the hybrid vehicle system according to the present disclosure, battery overheating can be suppressed even when the battery load of the secondary battery is large during heating at a cryogenic temperature.

1 is a configuration diagram of a hybrid vehicle system according to an embodiment. It is a detailed block diagram of the air-conditioning and battery cooling part in FIG. It is a figure which shows the example of the charging / discharging restriction | limiting relation file in FIG. 4 is a flowchart showing a procedure of battery overheat suppression control in the hybrid vehicle system according to the embodiment. FIG. 3 is a diagram illustrating a refrigerant flow in a cooling mode in the air conditioning / battery cooling unit in FIG. 2. FIG. 3 is a diagram showing a refrigerant flow in a heating mode in the air conditioning / battery cooling unit of FIG. 2.

  Hereinafter, a hybrid vehicle system according to an embodiment will be described in detail with reference to the drawings. In the following, a refrigeration cycle will be described as a configuration of an air conditioning / battery cooling unit that supplies a common refrigerant to the vehicle interior air conditioning unit and the secondary battery cooling unit. It may be a configuration. For example, a combination of a refrigeration cycle and a cooling water circulation circuit may be used.

  Below, the same code | symbol is attached | subjected to the same element in all the drawings, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a configuration diagram of a hybrid vehicle system 10 in the present embodiment. Hereinafter, a hybrid vehicle equipped with a hybrid vehicle system is referred to as a vehicle unless otherwise specified. The hybrid vehicle system 10 includes a main body 11 and a control device 40 that controls the operation of the components of the main body 11 as a whole. The main body 11 includes an engine 12, a rotating electric machine block 14, a power control unit 16 indicated as PCU (abbreviation of Power Control Unit), a secondary battery 20, and an air conditioning / battery cooling unit 60.

  The engine 12 is an internal combustion engine mounted on a vehicle. The rotating electrical machine block 14 includes two rotating electrical machines indicated as MG1 and MG2. MG1 and MG2 are both motor generators (Motor / Generator: MG) mounted on the vehicle, and act as an electric motor while the vehicle is running, and act as a generator when the vehicle is braked. It is. MG1 is driven by the engine 12, and mainly functions as a generator, and MG2 mainly functions as a motor for driving the vehicle. The power control unit 16 includes an inverter circuit connected to the rotating electrical machine block 14 and a step-up / down converter provided between the secondary battery 20 and the inverter circuit.

  The secondary battery 20 is a high voltage battery in which a plurality of battery cells are combined to output a predetermined high voltage and large current. An example of the voltage between the terminals of the secondary battery 20 is about 200 to 300V. Although FIG. 1 shows the secondary battery 20 in which a plurality of battery cells are connected in series, the secondary battery 20 is an appropriate combination of series connection and parallel connection according to the specifications of the output high voltage and large current. It's okay. As the types of battery cells, lithium ion battery cells, nickel metal hydride battery cells, and the like are used.

The secondary battery 20 is accommodated in the battery pack case 21 and cooled by the air conditioning / battery cooling unit 60. The battery temperature detection unit 22 is a temperature detection unit that detects a battery temperature θ _B that is the temperature of the secondary battery 20. The battery voltage detection unit 24 is a voltage detection unit that detects a battery voltage V that is a voltage between terminals of the secondary battery 20. The charge / discharge current detection unit 26 is a current detection unit that detects a discharge current from the secondary battery 20 and a charge / discharge current I that is a charge current from the secondary battery 20. The battery voltage detection unit 24 and the charge / discharge current detection unit 26 constitute a battery load detection unit 28 that detects a battery load that is a charge / discharge power load of the secondary battery 20. The detected battery temperature θ _B , battery voltage V, and charging / discharging current I data are transmitted to the control device 40 through appropriate signal lines.

Outside air temperature detector 34 is a temperature detecting means for detecting the outside air temperature theta _O of the vehicle. The outside air temperature detection unit 34 is provided, for example, in the vicinity of a radiator disposed on the front side of the vehicle, and the detected outside air temperature θ _O data is transmitted to the control device 40 through an appropriate signal line.

  The air conditioning / battery cooling unit 60 is the same for the vehicle interior air conditioning unit 62 that performs air conditioning in the vehicle interior of the vehicle and the secondary battery cooling unit 64 that cools the secondary battery 20, depending on the configuration known as a heat pump or a refrigeration cycle. It is integrated into a system that uses a refrigerant. Since the heat pump or the refrigeration cycle is the same, the heat pump is hereinafter referred to as a heat pump.

  As shown in FIG. 2, the basic configuration of the heat pump includes an accumulator 72, a compressor 74, an outdoor unit 78, a blower fan 80, an expansion valve 84, and an evaporator 86. When the passenger compartment air-conditioning unit 62 is in the cooling mode, the compressor 74 sucks the refrigerant contained in the accumulator 72 into high-pressure high-temperature gas, and the outdoor unit 78 dissipates the high-pressure high-temperature gas to condense it into a low-temperature liquid. Work as a vessel. The expansion valve 84 adiabatically expands the low temperature liquid to partially vaporize it, and the evaporator 86 absorbs heat by evaporation of all the low temperature liquid. Since the configuration and operation of these elements, the refrigerant used, and the like are well known as a heat pump or a refrigeration cycle, further description is omitted.

  The air conditioning / battery cooling unit 60 includes a three-way valve 76, a heater core 92, and an expansion valve 94 in order to use the heat pump in the heating mode of the vehicle interior air conditioning unit 62. In the heating mode, the heater core 92 serves as a condenser for the high-pressure and high-temperature gas compressed by the compressor 74. In the heating mode, the outdoor unit 78 acts as an evaporator that is a heat absorber rather than a radiator. In the heating mode, the blower fan 80 is not driven.

  The vehicle interior air conditioning unit 62 has an air conditioning duct 66 as an indoor unit. In the air conditioning duct 66, an evaporator 86 that operates in the cooling mode and a heater core 92 that operates in the heating mode are provided. The air in the vehicle compartment is taken in from the blower 68 on the air intake side, and the air blowing is performed. Return to the passenger compartment from the exit 69 side. The flow path switching door 70 provided in the air conditioning duct 66 corresponds to the cooling mode or the heating mode so that the cold air cooled by the evaporator 86 or the warm air heated by the heater core 92 flows to the air outlet 69. The flow in the air conditioning duct 66 is switched.

  The secondary battery cooling unit 64 has a branch refrigerant path 88 and an expansion valve 90. The branch refrigerant path 88 is a refrigerant path arranged in parallel with the refrigerant path to the evaporator 86 used when the vehicle interior air conditioning unit 62 is in the cooling mode. That is, the branch refrigerant path 88 is connected at one end to a refrigerant supply path through which refrigerant is supplied to the evaporator 86 used when the vehicle interior air conditioning unit 62 is in the cooling mode, and the refrigerant is returned from the evaporator 86 to the accumulator 72 side. The other end is connected to the refrigerant return path. The expansion valve 90 is provided on one end side of the branch refrigerant path 88. The branch refrigerant path 88 extends from one end side to the battery pack case 21 side, enters the inside of the battery pack case 21 through an appropriate connection portion, and contacts the bottom portion of the secondary battery 20 for heat exchange. Then, it makes a U-turn and returns to the other end side through the connecting portion.

  The check valve 82 is provided in the middle of a pipe line connecting the outdoor unit 78 and the expansion valve 84, allows refrigerant to flow from the outdoor unit 78 side to the expansion valves 84 and 90, and from the expansion valve 84 side to the outdoor side. It has a function of blocking the flow of refrigerant toward the machine 78 side.

  Details of the operation of the air conditioning / battery cooling unit 60 in the cooling mode, the heating mode, and the like will be described later with reference to FIGS. 5 and 6 in the description of FIG.

  Returning to FIG. 1, the air conditioning mode SW 36 is an operator that is operated by the user and sets the air conditioning mode of the passenger compartment to any one of the cooling mode, the heating mode, and the air conditioning stop mode. The mode set by the air conditioning mode SW 36 is transmitted to the control device 40 via an appropriate signal line.

  The memory 42 connected to the control device 40 is a memory that is connected to the control device 40 and stores programs used in the control device 40, data of arithmetic processing, and the like. In particular, a charge / discharge restriction relation file 44 relating to the secondary battery 20 is stored.

FIG. 3 is a diagram illustrating an example of the charge / discharge restriction relation file 44. The charge / discharge restriction relation file 44 is a map showing the restriction of charge / discharge power on the high temperature side of the secondary battery 20 with respect to the battery temperature θ _B. Although charge / discharge control is performed also on the low temperature side, it is omitted in FIG. The horizontal axis is the battery temperature θ _B of the secondary battery 20, the vertical axis is the discharge power limit value W _OUT of the secondary battery 20, and the negative axis is the charge power of the secondary battery 20. This is the limit value W _IN . The discharge power limiting characteristic 100 and the charging power limiting characteristic 102 of the secondary battery 20 are indicated by solid lines, respectively. The high temperature side threshold temperature θ _B2 is shown on the horizontal axis. The high temperature side threshold temperature θ _B2 is the charge / discharge restriction start temperature on the high temperature side, and limits W _OUT and W _IN on the high temperature side. As the battery temperature θ _B becomes higher than θ _B2 , the discharge power limiting characteristic 100 becomes the discharge power limiting characteristic 101 where W _OUT gradually decreases, and the charging power limiting characteristic 102 is the charging power limiting characteristic 103 where W _IN gradually decreases. Become. The map as shown in FIG. 3 can be obtained in advance for the secondary battery 20 by simulation or experiment.

In FIG. 3, the discharge power restriction characteristic 100 and the charge power restriction characteristic 102 are shown in a map format as the charge / discharge restriction relation file 44. Other than this, a lookup table format, a mathematical relationship, a ROM format that outputs W _OUT and W _IN at that temperature by inputting the battery temperature θ _B may be used.

The control device 40 is a device for overall control of the operation of each element of the main body unit 11, and in particular, the heating mode is set at an extremely low temperature of the outside air temperature θ _O of −10 ° C. or lower, and further the battery of the secondary battery 20. When the load is large, secondary battery overheat suppression control for suppressing overheating of the secondary battery 20 is performed. The control device 40 controls the air conditioning / battery cooling unit 60 according to the setting of the air conditioning mode SW 36, and θ _B , V, I, θ transmitted from the battery temperature detection unit 22, the battery load detection unit 28, and the outside air temperature detection unit 34. _O is acquired, and the charge / discharge restriction relation file 44 is referred to by communicating with the memory 42. The control device 40 includes an air conditioning mode determination unit 46 that determines whether or not the air conditioning mode is a heating mode, an outside air temperature determination unit 48 that determines whether or not the outside air temperature θ _O is equal to or lower than a predetermined temperature, a battery load determination unit 50, and A charge / discharge limiting unit 52 is included.

  These functions of the control device 40 can be realized by the control device 40 executing software. Specifically, the control device 40 is realized by executing each processing procedure of the battery overheat suppression program. A part of the above functions may be realized by hardware.

  The operation of the above configuration, in particular, each function of the control device 40 will be described in more detail with reference to FIGS.

FIG. 4 shows the procedure of the battery overheat suppression control that is in the heating mode when the outside air temperature θ _O is at a very low temperature of −10 ° C. or less and further suppresses overheating of the secondary battery 20 when the battery load of the secondary battery 20 is large. It is a flowchart to show. Each procedure corresponds to each processing procedure of the battery overheat suppression program executed in the control device 40. When a vehicle control system is started by an ignition switch or the like in the vehicle, a battery overheat suppression program is started through a system initialization process.

  First, it is determined whether or not the request for vehicle interior air conditioning is in the heating mode (S10). This processing procedure is executed by the function of the air conditioning mode determination unit 46 of the control device 40. Specifically, when the setting data transmitted from the air conditioning mode SW36 is “heating mode”, the determination in S10 is affirmed and the process proceeds to S12.

In other “cooling mode” and “air-conditioning stop mode”, S10 is denied and the process proceeds to S18. S18 relates to the charge / discharge restriction process for the battery temperature θ _B of the secondary battery 20, but here, charge / discharge restriction is performed as usual. The normal charge / discharge control is control for limiting the charge / discharge power at the battery temperature θ _B2 or higher according to the discharge power limit characteristics 100 and 101 and the charge power limit characteristics 102 and 103 described in FIG.

  Here, the flow of the refrigerant in the air conditioning / battery cooling unit 60 will be described in the order of the cooling mode, the air conditioning stop mode, and the heating mode with reference to FIGS. 5 and 6.

  FIG. 5 is a diagram showing a path through which a refrigerant flows in the air conditioning / battery cooling unit 60 with a thick line in the cooling mode. In the cooling mode, the blower 68 and the blower fan 80 are driven, and the flow path switching door 70 is set so that the air flowing through the air conditioning duct 66 does not pass through the heater core 92. The three-way valve 76 is set so that the refrigerant flows from the compressor 74 to the outdoor unit 78 side.

  In the cooling mode, the refrigerant flows as follows. The low-pressure and low-temperature gas in the accumulator 72 is sucked up by the compressor 74 and becomes high-pressure and high-temperature gas. The high-pressure and high-temperature gas passes through the three-way valve 76 and is cooled by the blower 80 in the outdoor unit 78, and the high-pressure and high-temperature gas is condensed into a low-temperature and high-pressure liquid by heat radiation. The condensed low-temperature and high-pressure liquid passes through the check valve 82, adiabatically expands through the expansion valve 84, partially vaporizes, and all the low-temperature liquid evaporates in the evaporator 86. The air in the passenger compartment flowing through the car absorbs heat and cools it. The cooled air is returned from the air outlet 69 side to the vehicle interior, thereby cooling the vehicle interior.

  Part of the low-temperature and high-pressure liquid that has passed through the check valve 82 enters one end of the branch refrigerant path 88. The low-temperature and high-pressure gas that has entered the branch refrigerant path 88 is adiabatically expanded through the expansion valve 84 and partially vaporized, becomes a low-temperature wet gas, passes through the connection portion of the battery pack case 21, and is stored in the battery pack case 21. Enter inside. Inside the battery pack case 21, the secondary battery 20 is brought into contact with the bottom of the secondary battery 20 to absorb heat, cool and vaporize. The vaporized gas returns by making a U-turn through the branch refrigerant path 88 and returns to the accumulator 72. Thereby, the secondary battery 20 is cooled.

  In the air conditioning stop mode, the operation of the blower 68 provided in the air conditioning duct 66 is stopped in the cooling mode state. Note that the refrigerant is not supplied to the expansion valve 84 and the evaporator 86 by an appropriate means such as a switching valve. As a result, cold air is not sent into the passenger compartment, but low-temperature and high-pressure gas flows through the branch refrigerant path 88, and the secondary battery 20 can be cooled.

  FIG. 6 is a diagram showing a path through which a refrigerant flows in the air conditioning / battery cooling unit 60 with a thick line in the heating mode. In the heating mode, the blower 68 is driven, the blower fan 80 is stopped, and the flow path switching door 70 is set so that the air flowing through the air conditioning duct 66 passes through the heater core 92. The three-way valve 76 is set so that the refrigerant flows from the expansion valve 94 side to the outdoor unit 78 side. Note that the refrigerant is not supplied to the expansion valve 84 and the evaporator 86 by an appropriate means such as a switching valve. The air in the passenger compartment sent into the air conditioning duct 66 by the blower 68 flows through the evaporator 86 toward the heater core 92.

  In the heating mode, the refrigerant flows as follows. The low-pressure and low-temperature gas in the accumulator 72 is sucked up by the compressor 74 and becomes high-pressure and high-temperature gas. The high pressure and high temperature gas does not flow to the three-way valve 76 side but flows to the heater core 92. In the heater core 92, heat is exchanged with the air in the passenger compartment flowing through the air conditioning duct 66 to dissipate heat, and the heat is condensed into a low-temperature and high-pressure liquid. The air in the passenger compartment flowing through the air conditioning duct 66 is warmed by the heater core 92 and returned to the passenger compartment from the air outlet 69 side. As a result, the passenger compartment is heated.

  The low-temperature and high-pressure liquid condensed in the heater core 92 is adiabatically expanded through the expansion valve 94 and partially vaporized, and flows to the outdoor unit 78 via the three-way valve 76. In the outdoor unit 78, all the low-temperature liquid evaporates due to heat absorption from the outside air and enters one end of the branch refrigerant path 88. The gas that has entered the branch refrigerant path 88 is adiabatically expanded and cooled through the expansion valve 84 and enters the inside of the battery pack case 21 through the connection portion of the battery pack case 21. Inside the battery pack case 21, the secondary battery 20 is absorbed by the bottom of the secondary battery 20 and cooled. Thereafter, the branch refrigerant path 88 is U-turned back to return to the accumulator 72. Thereby, the secondary battery 20 is cooled.

Returning to FIG. 4 again, if the determination in S10 is affirmative, it is next determined whether or not the outside air temperature θ _O is equal to or lower than a predetermined temperature (S12). This processing procedure is executed by the function of the outside air temperature determination unit 48 of the control device 40.

As described with reference to FIG. 6, the gas entering the branch refrigerant path 88 in the heating mode is obtained by evaporating the low-temperature liquid in the outdoor unit 78 due to heat absorption from the outside air. If the outside air temperature is too low, heat is taken from the gas heated by the compressor 74, liquefaction occurs in the outdoor unit 78, and the gas pressure decreases. When the liquefied and reduced pressure refrigerant is supplied to the branch refrigerant path 88, the cooling effect due to adiabatic expansion in the expansion valve 90 is reduced, and the cooling capacity for the secondary battery 20 is reduced. The predetermined temperature in S12 means that in the heating mode, the outside air temperature θ _O is too low, heat is taken away from the gas heated by the compressor 74, and the cooling effect by the expansion valve 90 in the secondary battery cooling unit 64 is sufficient. It is the temperature that does not. In a general air conditioner, it is known that the heating performance deteriorates when the outside air temperature is about −10 ° C. or lower. Here, the predetermined temperature is −10 ° C. This temperature is an illustrative example, and can be appropriately changed depending on the specifications of the air conditioning / battery cooling unit 60.

If the value of the outside air temperature θ _O transmitted from the outside air temperature detector 34 is equal to or lower than −10 ° C., which is the predetermined temperature, the determination in S12 is affirmed, and the process proceeds to S14. When the outside air temperature θ _O exceeds the predetermined temperature, the cooling effect by the expansion valve 90 in the secondary battery cooling unit 64 is sufficient, so the process proceeds to S18.

If the determination in S12 is affirmative, it is determined whether or not the battery load of the secondary battery 20 is equal to or greater than a predetermined value _Wth (S14). This processing procedure is executed by the function of the battery load determination unit 50 of the control device 40. The battery load is obtained by calculating I ² and IV related to charge / discharge load power from the data of the battery voltage V and the charge / discharge current I transmitted from the battery load detector 28. The predetermined value W _th is a value set as charge / discharge power that may cause the secondary battery 20 to overheat. Even when the temperature is low, the running load of the vehicle is heavy, the battery load from the secondary battery 20 is heavy, and (charge / discharge current I) ² becomes large. In that case, the secondary battery 20 may be overheated. In particular, there is a possibility that a cell having a high internal resistance among the battery cells constituting the secondary battery 20 may be abnormally overheated. S14 is a processing procedure for determining whether or not the secondary battery 20 may be overheated. If the determination in S14 is affirmative, the process proceeds to S16. If the determination in S16 is negative, there is no possibility of overheating of the secondary battery 20, so the process proceeds to S18.

If the determination in S14 is affirmative, the charge / discharge restriction is shifted to a lower temperature side of the battery temperature θ _B than in the normal process described in S18 (S16). This processing procedure is executed by the function of the charge / discharge limiting unit 52 of the control device 40 as in S18. FIG. 3 shows an example of shifting the high temperature side threshold temperature θ _B2 related to the charge / discharge limitation to the low temperature side of the battery temperature θ _B by a broken line. Here, the battery temperature θ _B shifted Δθ _BA from θ _B2 to the low temperature side is defined as the battery temperature (θ _B2 −Δθ _BA ). As for the discharge limitation, the discharge power limitation characteristic 104 is shown in which W _OUT gradually decreases from the discharge power limitation characteristic 100 as the battery temperature (θ _B2 −Δθ _BA ) increases. Similarly, the charging limitation shows a charging power limiting characteristic 106 in which W _OUT gradually decreases from the charging power limiting characteristic 102 as the battery temperature (θ _B2 −Δθ _BA ) becomes higher. Compared to the normal processing described in S18 for charging / discharging limitation, overheating of the secondary battery 20 can be suppressed by shifting the high temperature side threshold temperature θ _B2 to the low temperature side of the battery temperature θ _B.

The hybrid vehicle system 10 according to the present embodiment includes an air conditioning / battery cooling unit 60 that supplies a common refrigerant to the vehicle interior air conditioning unit 62 and the secondary battery cooling unit 64. Further, the hybrid vehicle system 10 includes an outside air temperature detection unit 34 that detects the outside air temperature θ _{O of the} vehicle, a battery load detection unit 28 that detects a battery load due to charging / discharging of the secondary battery 20, and a battery of the secondary battery 20. And a battery temperature detection unit 22 for detecting the temperature θ _B. Moreover, the hybrid vehicle system 10 includes a control device 40 that limits the charge / discharge power of the secondary battery 20 according to the battery temperature θ _B. The control device 40 has three conditions: the outside air temperature θ _O is a low temperature that is equal to or lower than a predetermined temperature, the vehicle interior air conditioning is in a heating mode, and the battery load of the secondary battery 20 is equal to or higher than a predetermined power value. It is determined whether or not it is satisfied. When the three conditions are satisfied, the charge / discharge power limit is shifted to the lower temperature side of the battery temperature θ _B than when at least one of the three conditions is not satisfied. According to the hybrid vehicle system 10, overheating of the secondary battery 20 can be suppressed even when the battery load of the secondary battery 20 is large during heating at an extremely low temperature of −10 ° C. or less.

  DESCRIPTION OF SYMBOLS 10 Hybrid vehicle system, 11 Main part, 12 Engine, 14 Rotating electrical machine block, 16 Electric power control unit (PCU), 20 Secondary battery, 21 Battery pack case, 22 Battery temperature detection part, 24 Battery voltage detection part, 26 Charging / discharging Current detection unit, 28 Battery load detection unit, 34 Outside air temperature detection unit, 36 Air conditioning mode SW, 40 Control device, 42 Memory, 44 Charge / discharge restriction relation file, 46 Air conditioning mode determination unit, 48 Outside air temperature determination unit, 50 Battery load Judgment unit, 52 Charge / discharge limiting unit, 60 Air conditioning / battery cooling unit, 62 Car interior air conditioning unit, 64 Secondary battery cooling unit, 66 Air conditioning duct, 68 Blower, 69 Air outlet, 70 Channel switching door, 72 Accumulator , 74 Compressor, 76 Three-way valve, 78 Outdoor unit, 80 Blower, 82 Check valve, 84,90,94 expansion valve, 86 an evaporator, 88 branch coolant passage, 92 a heater core, 100,101,104 discharge power limitation characteristic, 102,103,106 charging power limitation characteristic.

Claims (1)

An air conditioning / battery cooling unit that supplies a common refrigerant to the vehicle interior air conditioning unit and the secondary battery cooling unit;
An outside temperature detector for detecting the outside temperature of the vehicle;
A battery load detector for detecting a battery load due to charging / discharging of the secondary battery;
A battery temperature detector for detecting a battery temperature of the secondary battery;
A control device that limits charge / discharge power of the secondary battery according to the battery temperature;
With
The controller is
When the outside air temperature is a low temperature below a predetermined temperature, the vehicle interior air conditioning is in a heating mode, and the battery load of the secondary battery is above a predetermined power value, A hybrid vehicle system that shifts the limit of the charge / discharge power to a lower temperature side of the battery temperature than when not satisfying at least one of the three conditions.

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