KR20230086357A - Method for controlling charging of vehicle battery - Google Patents

Abstract

According to the charging control method for a vehicle battery according to an embodiment of the present invention, when charging of the battery starts, it is determined whether the towing is fastened, and when the towing is fastened, it is determined whether the temperature of the battery is equal to or higher than the limit temperature, and the temperature of the battery is determined. When is greater than the limit temperature, the charging current for the battery may be controlled to a first limit charging current so that the temperature of the battery does not reach the power limit temperature. The power limit temperature may be a temperature of a battery at which power output from the battery is lowered below a set value.

Description

Charging control method of vehicle battery {METHOD FOR CONTROLLING CHARGING OF VEHICLE BATTERY}

The present invention relates to a charging control method for a vehicle battery, and more particularly, to prevent power output from a battery from being relatively lowered when the battery is charged or rapidly charged in a driving condition in which an electric vehicle is driven in a towing mode. It relates to a charging control method of a vehicle battery.

Recently, as interest in energy efficiency and environmental pollution issues has grown day by day, there is a demand for the development of eco-friendly vehicles that can substantially replace internal combustion engine vehicles. and hybrid vehicles powered by batteries.

In the electric vehicle, the electric vehicle may operate in the towing mode to tow another vehicle such as a camper by selecting a towing mode through a control panel disposed in an AVN or a cluster by a driver or a passenger. The controller may receive the towing connection status from the towing controller, and through this, it is possible to check whether the towing connection of the electric vehicle has been made.

On the other hand, when the electric vehicle is driven in the towing mode, the power load required for the electric vehicle relatively increases, and thus the battery usage may relatively increase, so charging or rapid charging of the battery is required. However, when the battery is charged or rapidly charged, the SOC of the battery may increase, but the temperature of the battery may increase excessively due to the charging or rapid charging. Electric power may be limited. Although the SOC of the battery is sufficient, the power output from the battery may be relatively low due to the excessively high temperature of the battery, and as a result, it may be difficult to secure sufficient driving performance as soon as the electric vehicle starts. In particular, when the electric vehicle goes up a hill while driving in towing mode, a safety problem arises because sufficient vehicle speed cannot be secured as the power output from the battery is relatively low.

Matters described in this background art section are prepared to enhance understanding of the background of the invention, and may include matters that are not prior art already known to those skilled in the art to which this technique belongs.

The present invention has been devised in consideration of the above points, and is a vehicle battery that can prevent the power output from the battery from being relatively lowered when the battery is charged or rapidly charged in a driving condition in which the electric vehicle is driven in the towing mode. Its purpose is to provide a charging control method.

According to the charging control method for a vehicle battery according to an embodiment of the present invention for achieving the above object, when charging of the battery starts, it is determined whether the towing is fastened, and when the towing is fastened, whether the temperature of the battery is higher than the limit temperature or not. and when the temperature of the battery is equal to or greater than the limit temperature, the charging current for the battery may be controlled to a first limit charging current so that the temperature of the battery does not reach the power limit temperature. The power limit temperature may be a temperature of a battery at which power output from the battery is lowered below a set value.

The first limiting charging current may be a charging current determined to be lower than an initial charging current set when charging of the battery starts.

The limit temperature may be a temperature obtained by subtracting a certain margin temperature from the power limit temperature.

If the toeing is not fastened, the charging current of the battery or the battery may be controlled to the second limiting charging current so that the temperature of the battery does not reach the high temperature limiting temperature. The high temperature limit temperature may be a temperature of a battery at a high temperature at which the battery may be damaged.

The second limiting charging current may be a charging current determined to be lower than an initial charging current set when charging of the battery starts.

The high temperature limit temperature may be higher than the power limit temperature.

According to the present invention, when the battery is charged (quickly charged) according to whether or not the toeing is fastened, the power output from the battery can be prevented from deteriorating by appropriately controlling the charging current to prevent the temperature of the battery from excessively rising. Therefore, it may be difficult to secure sufficient driving performance as soon as the electric vehicle starts. In particular, when the electric vehicle goes uphill while driving in towing mode, sufficient vehicle speed can be secured because power output from the battery can be sufficiently secured, thereby preventing safety problems from occurring.

1 is a block diagram showing a control structure connected to a vehicle battery according to an embodiment of the present invention.
2 is a diagram illustrating an example of a vehicle thermal management system for cooling a vehicle battery.
3 is a flowchart illustrating a charging control method of a vehicle battery according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. In adding reference numerals to components of each drawing, it should be noted that the same components have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing an embodiment of the present invention, if it is determined that a detailed description of a related known configuration or function hinders understanding of the embodiment of the present invention, the detailed description will be omitted.

In describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, order, or order of the corresponding component is not limited by the term. In addition, unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present application, they should not be interpreted in an ideal or excessively formal meaning. don't

Referring to FIG. 1 , the battery 41 may be mounted on the floor of a vehicle or the like, and the battery 41 may be configured to supply electric power to an electric motor or the like. The battery 41 may be charged by the charger 130, the charger 130 may charge the battery 41 using an external power source, and the charge controller 120 may determine an appropriate charging current. The battery 41 may be managed by a battery management system 110 (BATTERY MANAGEMENT SYSTEM), and the battery management system 110 monitors the state of the battery 41 and determines whether the temperature of the battery 41 exceeds a set temperature. When high, the battery 41 may be cooled by the battery cooling subsystem 12 (see FIG. 2). When the battery 41 is charged, the temperature of the battery 41 rises, so the controller 100 receives state information of the battery 41 from the battery management system 110, and the controller 100 adjusts the vehicle thermal management system appropriately. By controlling, the battery cooling subsystem 12 can properly cool the battery 41 . In particular, when the battery 41 is rapidly charged, the temperature of the battery 41 may also rise rapidly. Cooling may reach its limit and no further cooling may be achieved.

The electric vehicle may have a towing fastening structure provided at its rear, and when an external vehicle (camper, trailer, carrier, etc.) is fastened to the towing fastening structure of the electric vehicle, the towing controller 150 determines whether the towing fastening is a controller ( 100) can be transmitted. When the controller 100 confirms the towing connection, the controller 100 may set a relatively large power load for the electric vehicle, and thus the electric vehicle may run in the towing mode by the controller 100. When the electric vehicle is driven in the towing mode, the battery 41 is required to be charged since its usage increases.

Meanwhile, when the battery 41 is charged or rapidly charged, the SOC of the battery 41 may increase, and at the same time, the temperature of the battery 41 may increase. In particular, when the battery 41 is charged or rapidly charged in driving conditions of an electric vehicle requiring a relatively large power load, such as the towing mode, the temperature of the battery 41 excessively rises, resulting in damage from the battery 41. Power output from the electric motor may be relatively low, and due to this, it may be difficult to secure sufficient driving performance as soon as the electric vehicle starts. In particular, when the electric vehicle goes uphill while driving in the towing mode, since the power output from the battery 41 is relatively low, sufficient vehicle speed cannot be secured, resulting in safety problems. Accordingly, when the battery 41 is charged or rapidly charged in driving conditions of an electric vehicle requiring a large power load such as towing mode, it is necessary to maintain the temperature of the battery 41 at a level to maintain a stable output. 41 may be cooled by the battery cooling subsystem 12 (see FIG. 2).

2 is a diagram illustrating an example of a thermal management system for a vehicle including a battery cooling subsystem 12 . Referring to FIG. 2 , the thermal management system for a vehicle includes an air conditioning subsystem (HVAC subsystem) 11 including a refrigerant loop 21 through which refrigerant circulates, and a battery coolant loop 22 through which coolant for cooling a battery 41 circulates. A battery cooling subsystem (12) including a battery cooling subsystem (12) and a powertrain cooling subsystem including a powertrain cooling water loop (23) in which cooling water for cooling the electric motor 51 and electric components 52 of the powertrain circulates system 13, power train cooling subsystem.

The air conditioning subsystem 11 may be configured to heat or cool air in a passenger compartment of a vehicle by means of a refrigerant circulating in the refrigerant loop 21 . The refrigerant loop 21 includes an evaporator 31, a compressor 32, an internal condenser 33, an expansion valve 16 on the heating side, a water-cooled heat exchanger 70, an external heat exchanger 35, and a cooling side. It can be fluidly connected to the expansion valve 15. 1, the refrigerant passes through the refrigerant loop 21 through the compressor 32, the inner condenser 33, the heating expansion valve 16, the water-cooled heat exchanger 70, the outer heat exchanger 35, and the cooling expansion valve. (15) and the evaporator (31) in this order.

The evaporator 31 may be configured to evaporate the refrigerant supplied from the cooling-side expansion valve 15 . That is, the refrigerant expanded by the cooling-side expansion valve 15 can be evaporated by absorbing heat from the air in the evaporator 31 . Accordingly, during the cooling operation of the air conditioning subsystem 11, the evaporator 31 uses the refrigerant cooled by the external heat exchanger 35 and expanded by the cooling-side expansion valve 15 to release air flowing into the passenger compartment. Can be configured to cool.

The compressor 32 may be configured to compress the refrigerant received from the evaporator 31 and/or the battery chiller 37 . According to one example, compressor 32 may be an inverter compressor including an inverter 80 .

The compressor 32 may include a compressor motor and a compression section operated by the compressor motor. The refrigerant loop 21 may be fluidly connected to the compression unit of the compressor 32 .

The inner condenser 33 may be configured to condense the refrigerant supplied from the compressor 32 , and air passing through the inner condenser 33 may be heated by the inner condenser 33 . As the air heated by the inner condenser 33 flows into the passenger compartment, the passenger compartment can be heated.

The external heat exchanger 35 may be disposed adjacent to the front grill of the vehicle, and since the external heat exchanger 35 is exposed to the outside, heat may be transferred between the external heat exchanger 35 and the outside air. During the cooling operation of the air conditioning subsystem 11 , the external heat exchanger 35 may be configured to condense the refrigerant supplied from the internal condenser 33 . That is, the external heat exchanger 35 may function as an external condenser condensing the refrigerant by transferring heat to the outside air during the cooling operation of the air conditioning subsystem 11 . During the heating operation of the air conditioning subsystem 11 , the external heat exchanger 35 may be configured to evaporate the refrigerant supplied from the water-cooled heat exchanger 70 . That is, the external heat exchanger 35 may function as an external evaporator for evaporating the refrigerant by absorbing heat from the outside air during the heating operation of the air conditioning subsystem 11 . In particular, the outside heat exchanger 35 exchanges heat with outside air forcibly blown by the cooling fan 75, so that a heat transfer rate between the outside heat exchanger 35 and the outside air can be further increased.

The water-cooled heat exchanger 70 includes a refrigerant loop 21 of the air conditioning subsystem 11, a battery coolant loop 22 of the battery cooling subsystem 12, and a powertrain coolant loop of the powertrain cooling subsystem 13 ( 23) may be configured to transfer heat between them. Specifically, the water-cooled heat exchanger 70 may be disposed between the indoor condenser 33 and the outdoor heat exchanger 35 on the refrigerant loop 21 . The water-cooled heat exchanger 70 includes a first passage 71 fluidly connected to the power train cooling water loop 23, a second passage 72 fluidly connected to the battery cooling water loop 22, and a refrigerant loop 21 ) and a third passage 73 fluidly connected.

During the heating operation of the air conditioning subsystem 11, the water-cooled heat exchanger 70 may be configured to evaporate the refrigerant supplied from the indoor condenser 33 by heat transferred from the powertrain cooling subsystem 13. . That is, during the heating operation of the air conditioning subsystem 11, the water-cooled heat exchanger 70 recovers the waste heat generated from the electric motor 51 and the electric component 52 of the powertrain cooling subsystem 13 to recover the refrigerant. It can act as an evaporator for evaporation.

The water-cooled heat exchanger 70 may be configured to condense the refrigerant received from the inner condenser 24 during the cooling operation of the air conditioning subsystem 11 . The water-cooled heat exchanger 70 includes battery cooling water circulating in the battery cooling water loop 22 of the battery cooling subsystem 12 and powertrain-side cooling water circulating in the powertrain cooling water loop 23 of the powertrain cooling subsystem 13. By cooling and condensing the refrigerant by the condenser may serve as a condenser for condensing the refrigerant.

The heating-side expansion valve 16 may be disposed upstream of the water-cooled heat exchanger 70 on the refrigerant loop 21 . Specifically, the heating-side expansion valve 16 may be disposed between the inner condenser 33 and the water-cooled heat exchanger 70 . The heating-side expansion valve 16 can control the flow or flow rate of the refrigerant flowing into the water-cooled heat exchanger 70 when the air conditioning subsystem 11 is heating, and the heating-side expansion valve 16 is It may be configured to expand the refrigerant supplied from the inner condenser 33 during the heating operation of the system 11 .

According to one example, the heating-side expansion valve 16 may be an electronic expansion valve (EXV) having a drive motor 16a. The drive motor 16a may have a shaft that moves to open and close an orifice defined in the valve body of the heating-side expansion valve 16, and the position of the shaft may vary depending on the rotation direction and degree of rotation of the drive motor 16a. Thereby, the opening degree of the orifice of the heating-side expansion valve 16 can be varied. The controller 100 may control the operation of the driving motor 16a. Also, the heating-side expansion valve 16 may be a full open type EXV.

The heating-side expansion valve 16 may be configured such that its opening degree is variable by the controller 100, and as the opening degree of the heating-side expansion valve 16 changes, the flow rate of the refrigerant flowing into the third passage 73 increases. can be variable The heating-side expansion valve 16 may be controlled by the controller 100 when the air conditioning subsystem 11 is heating.

The cooling-side expansion valve 15 may be disposed between the external heat exchanger 35 and the evaporator 31 on the refrigerant loop 21 . Since the cooling-side expansion valve 15 is disposed upstream of the evaporator 31, the flow or flow rate of the refrigerant flowing into the evaporator 31 can be adjusted. It may be configured to expand the refrigerant supplied from the external heat exchanger 35 during the cooling operation of the.

According to one embodiment, the cooling-side expansion valve 15 may be a thermal expansion valve (TXV) that controls the opening of the cooling-side expansion valve 15 by sensing the temperature and/or pressure of the refrigerant. Specifically, according to the embodiment, the cooling-side expansion valve 15 may be a thermal expansion valve having an on-off valve 15a capable of selectively blocking the flow of refrigerant into the internal oil of the cooling-side expansion valve 15, opening and closing. Valve 15a may be a solenoid valve. The opening/closing valve 15a can be opened and closed by the controller 100, thereby blocking or unblocking the flow of refrigerant into the cooling-side expansion valve 15. When the on-off valve 15a is opened, the refrigerant can be allowed to flow into the cooling-side expansion valve 15, and when the on-off valve 15a is closed, the flow of refrigerant into the cooling-side expansion valve 15 is blocked. It can be. According to one example, the on-off valve 15a may be integrally mounted inside the valve body of the cooling-side expansion valve 15 to open and close the internal passage of the cooling-side expansion valve 15 . According to another example, the on-off valve 15a may be configured to selectively open and close the inlet of the cooling-side expansion valve 15 by being disposed upstream of the cooling-side expansion valve 15 .

When the on/off valve 15a is closed, the cooling-side expansion valve 15 may be blocked, and thus the refrigerant does not flow into the cooling-side expansion valve 15 and the evaporator 31, but only flows toward the battery chiller 37. can enter That is, when the opening/closing valve 15a of the cooling-side expansion valve 15 is closed, the cooling operation of the air conditioning subsystem 11 is not executed, and only the battery chiller 37 is cooled or the air conditioning subsystem 11 is heated. operation can be performed. When the opening/closing valve 15a is opened, the refrigerant may flow into the cooling side expansion valve 15 and the evaporator 31 side. That is, when the opening/closing valve 15a of the cooling-side expansion valve 15 is opened, the air conditioning subsystem 11 may be cooled.

The air conditioning subsystem 11 may include an air conditioning case 30 having an inlet and an outlet, and the air conditioning case 30 may be configured to allow air to flow toward the passenger compartment of the vehicle. The evaporator 31 and the inner condenser 33 may be located in the air conditioning case 30 . An air mixing door 34a may be disposed between the evaporator 31 and the inner condenser 33, and a PTC heater 34b (Positive Temperature Coefficient heater) may be disposed downstream of the inner condenser 33.

The air conditioning subsystem 11 may further include an accumulator 38 disposed between the evaporator 31 and the compressor 32 on the refrigerant loop 21, the accumulator 38 downstream of the evaporator 31. can be located The accumulator 38 may be configured to prevent the liquid refrigerant from flowing into the compressor 32 by separating the liquid refrigerant from the refrigerant supplied from the evaporator 31 .

The air conditioning subsystem 11 may further include a branch conduit 36 branched from the refrigerant loop 21 . The branch conduit 36 branches from a point upstream of the cooling-side expansion valve 15 on the refrigerant loop 21 and may be connected to the compressor 32 . The battery chiller 37 may be fluidly connected to the branch conduit 36, and the battery chiller 37 may be configured to transfer heat between the branch conduit 36 and a battery cooling water loop 22 to be described later. That is, the battery chiller 37 may be configured to transfer heat between the refrigerant circulating on the air conditioning subsystem 11 and the battery cooling water circulating on the battery cooling subsystem 12 .

Specifically, the battery chiller 37 may include a first passage 37a fluidly connected to the branch conduit 36 and a second passage 37b fluidly connected to the battery cooling water loop 22. The first passage 37a and the second passage 37b may be disposed adjacent to or in contact with each other within the battery chiller 37, and the first passage 37a may be fluidically separated from the second passage 37b. can Accordingly, the battery chiller 37 may be configured to transfer heat between the battery cooling water passing through the second passage 37b and the refrigerant passing through the first passage 37a, and the refrigerant absorbs heat from the battery cooling water. It can vaporize and become overheated, and the battery coolant can be cooled by dissipating heat into the refrigerant.

The branch conduit 36 may be fluidly connected to the accumulator 38, and the refrigerant passing through the branch conduit 36 may be received in the accumulator 38.

A chiller-side expansion valve 17 may be disposed upstream of the battery chiller 37 on the branch conduit 36 . The chiller-side expansion valve 17 can adjust the flow or flow rate of the refrigerant flowing into the battery chiller 37, and the chiller-side expansion valve 17 expands the refrigerant supplied from the external heat exchanger 35. It can be.

According to one example, the chiller-side expansion valve 17 may be an electronic expansion valve (EXV) having a driving motor 17a. The drive motor 17a may have a shaft that moves to open and close an orifice defined in the valve body of the chiller-side expansion valve 17, and the position of the shaft may vary depending on the rotation direction and degree of rotation of the drive motor 17a. Thereby, the opening degree of the chiller-side expansion valve 17 can be varied. That is, the opening degree of the chiller-side expansion valve 17 can be varied by controlling the operation of the drive motor 17a by the controller 100. Also, the chiller-side expansion valve 17 may be a full open type EXV. The chiller-side expansion valve 17 may have the same or similar structure as the heating-side expansion valve 16 shown in FIG. 3 .

As the opening degree of the chiller-side expansion valve 17 is varied, the flow rate of the refrigerant flowing into the battery chiller 37 may be varied. For example, when the opening of the chiller-side expansion valve 17 is greater than the reference opening, the flow rate of the refrigerant flowing into the battery chiller 37 may be relatively higher than the reference flow, and the opening of the chiller-side expansion valve 17 is the reference. When the opening is smaller than the opening degree, the flow rate of the refrigerant flowing into the battery chiller 37 may be similar to the standard flow rate or may be relatively reduced than the standard flow rate. Here, the reference opening degree may be the opening degree of the chiller-side expansion valve 17 capable of maintaining the target evaporator temperature. The reference flow rate may be the flow rate of the refrigerant flowing into the battery chiller 37 when the chiller-side expansion valve 17 is opened to a standard opening degree. Accordingly, when the chiller-side expansion valve 17 is opened to a standard opening degree, the refrigerant may flow into the battery chiller 37 by a corresponding standard flow rate.

As the opening of the chiller-side expansion valve 17 is adjusted by the controller 100, the flow rate of the refrigerant flowing into the battery chiller 37 is changed, so the flow rate of the refrigerant flowing into the evaporator 31 can be varied. Accordingly, as the opening of the chiller-side expansion valve 17 is adjusted, the refrigerant can be distributed and flowed into the evaporator 31 and the battery chiller 37 at a predetermined rate, through which the cooling of the air conditioning subsystem 11 and the battery Cooling of the chiller 37 can be performed simultaneously or selectively.

The air conditioning subsystem 11 may further include a refrigerant bypass conduit 39 connecting a branch conduit 36 and a downstream point of the third passage 73 of the water-cooled heat exchanger 70 . An inlet of the refrigerant bypass conduit 39 may be connected to a downstream point of the water-cooled heat exchanger 70, and an outlet of the refrigerant bypass conduit 39 may be connected to the branch conduit 36. Specifically, the inlet of the refrigerant bypass conduit 39 may be connected to a point between the water-cooled heat exchanger 70 and the external heat exchanger 35, and the outlet of the refrigerant bypass conduit 39 is on the branch conduit 36. It may be connected to a point between the battery chiller 37 and the compressor 32. A first three-way valve 61 may be disposed at a connection point between the inlet of the refrigerant bypass conduit 39 and the refrigerant loop 21 . Accordingly, the first three-way valve 61 may be disposed between the external heat exchanger 35 and the water-cooled heat exchanger 70 on the refrigerant loop 21 . When the first three-way valve 61 is switched to open the inlet of the refrigerant bypass conduit 39, the refrigerant passing through the third passage 73 of the water-cooled heat exchanger 70 passes through the refrigerant bypass conduit 39. and into the compressor 32 through the accumulator 38. That is, when the inlet of the refrigerant bypass conduit 39 is opened by the switching of the first three-way valve 61, the refrigerant may bypass the external heat exchanger 35. When the first three-way valve 61 is switched to close the inlet of the refrigerant bypass conduit 39, the refrigerant passing through the third passage 73 of the water-cooled heat exchanger 70 passes through the refrigerant bypass conduit 39. It can flow into the external heat exchanger 35 without passing through. That is, when the inlet of the refrigerant bypass conduit 39 is closed by switching of the first three-way valve 61, the refrigerant may pass through the external heat exchanger 35.

The controller 100 may be configured to control individual operations of the on-off valve 15a of the cooling-side expansion valve 15, the heating-side expansion valve 16, the chiller-side expansion valve 17, the compressor 32, and the like, Through this, the overall operation of the air conditioning subsystem 11 can be controlled by the controller 100 . According to one embodiment, the controller 100 may be a Full Automatic Temperature Control System (FATC) or a vehicle controller.

When the air conditioning subsystem 11 operates in the cooling mode, the on-off valve 15a of the cooling-side expansion valve 15 is opened, and the refrigerant flows through the compressor 32, the inner condenser 33, and the heating-side expansion valve 16. ), the third passage 73 of the water-cooled heat exchanger 70, the external heat exchanger 35, the cooling-side expansion valve 15, and the evaporator 31 in this order.

When the air conditioning subsystem 11 operates in the heating mode, the on-off valve 15a of the cooling-side expansion valve 15 is closed, and the refrigerant flows through the compressor 32, the inner condenser 33, and the expansion valve 16 for heating. , the third passage 73 of the water-cooled heat exchanger 70, the external heat exchanger 35, the chiller-side expansion valve 17, the first passage 37a of the battery chiller 37, and the compressor 32 in this order. can do. Meanwhile, during the heating operation of the air conditioning subsystem 11, the on-off valve 15a of the cooling-side expansion valve 15 is closed and the inlet of the refrigerant bypass conduit 39 switches the first three-way valve 61. When opened, the refrigerant may circulate in the order of the compressor 32, the inner condenser 33, the expansion valve 16 for heating, the third passage 73 of the water-cooled heat exchanger 70, and the compressor 32. .

The battery cooling subsystem 12 may be configured to cool the battery 41 by battery cooling water circulating through the battery cooling water loop 22 . The battery coolant loop 22 includes a battery 41, a heater 42, a battery chiller 37, a second battery pump 45, a battery radiator 43, a reservoir tank 48, and a first battery pump 44. ) can be fluidly connected to. 1, the battery cooling water passes through the battery cooling water loop 22 to the battery 41, the heater 42, the battery chiller 37, the second battery pump 45, the battery radiator 43, and the reservoir tank 48. , the second passage 72 of the water-cooled heat exchanger 70, and the first battery pump 44 may flow sequentially.

The battery 41 may have a cooling water passage through which battery cooling water passes inside or outside thereof, and the battery cooling water loop 22 may be fluidly connected to the cooling water passage of the battery 41 .

The heater 42 may be disposed between the battery chiller 37 and the battery 41 , and the heater 42 may warm up the battery cooling water by heating the battery cooling water circulating through the battery cooling water loop 22 . According to one example, the heater 42 may be a water heater that heats cooling water by heat exchange with a high-temperature fluid. According to another example, the heater 42 may be an electric heater.

The battery radiator 43 may be disposed adjacent to a front grille of the vehicle, and the battery radiator 43 may be cooled by external air forcibly blown by the cooling fan 75 . The battery radiator 43 may be adjacent to the external heat exchanger 35 .

The first battery pump 44 can be configured to circulate the battery coolant along at least a portion of the battery coolant loop 22, and the second battery pump 45 circulates the battery coolant along at least a portion of the battery coolant loop 22. It can be configured to circulate along.

The first battery pump 44 may be disposed upstream of the battery 41 on the battery cooling water loop 22 . Accordingly, the first battery pump 44 may be configured to allow the battery cooling water to pass through the cooling water passage of the battery 41 by forcibly pumping the battery cooling water into the battery 41 .

The second battery pump 45 may be disposed upstream of the battery radiator 43 on the battery cooling water loop 22 . Accordingly, the second battery pump 45 may be configured to allow the battery cooling water to pass through the battery radiator 43 by forcibly pumping the battery cooling water to the inlet of the battery radiator 43 .

The first battery pump 44 and the second battery pump 45 may individually and selectively operate according to heating and charging conditions of the battery 41 and operating conditions of the air conditioning subsystem 11 .

The reservoir tank 48 may be disposed between the outlet of the battery radiator 43 and the inlet of the first battery pump 44 .

The battery cooling subsystem 12 may further include a first battery bypass conduit 46 configured to allow battery cooling water to bypass the battery radiator 43 . The first battery bypass conduit 46 may be configured to directly connect an upstream point of the battery radiator 43 and a downstream point of the battery radiator 43 on the battery cooling water loop 22 .

An inlet of the first battery bypass conduit 46 may be connected to a point between the inlet of the battery chiller 37 and the battery radiator 43 on the battery cooling water loop 22 . Specifically, the inlet of the first battery bypass conduit 46 may be connected to a point between the inlet of the battery chiller 37 and the second battery pump 45 on the battery cooling water loop 22 .

An outlet of the first battery bypass conduit 46 may be connected to a point between the outlets of the battery chiller 37 and the battery radiator 43 on the battery cooling water loop 22 . Specifically, the outlet of the first battery bypass conduit 46 may be connected to a point between the inlet of the first battery pump 44 and the outlet of the reservoir tank 48 on the battery cooling water loop 22 .

As the battery cooling water flows from the downstream side of the battery chiller 37 through the first battery bypass conduit 46 to the upstream side of the first battery pump 44, the battery cooling water flows through the second battery pump 45, the battery radiator ( 43), the reservoir tank 48, and the water-cooled heat exchanger 70 can be bypassed, and thus the battery cooling water passing through the first battery bypass conduit 46 is supplied by the first battery pump 44 to the battery ( 41), the heater 42, and the battery chiller 37 may flow sequentially.

Battery cooling subsystem 12 may further include a second battery bypass conduit 47 configured to allow battery cooling water to bypass battery 41 , heater 42 , and battery chiller 37 . . The second battery bypass conduit 47 may be configured to directly connect a downstream point of the battery chiller 37 and an upstream point of the battery 41 on the battery cooling water loop 22 .

An inlet of the second battery bypass conduit 47 may be connected to a point between an outlet of the first battery bypass conduit 46 and an outlet of the battery radiator 43 on the battery cooling water loop 22 . Specifically, the inlet of the second battery bypass conduit 47 may be connected to a point between the outlet of the first battery bypass conduit 46 and the outlet of the reservoir tank 48 on the battery coolant loop 22 .

The outlet of the second battery bypass conduit 47 may be connected to a point between the inlet of the first battery bypass conduit 46 and the inlet of the battery radiator 43 on the battery cooling water loop 22 . Specifically, the outlet of the second battery bypass conduit 47 may be connected to a point between the inlet of the first battery bypass conduit 46 and the inlet of the second battery pump 45 on the battery coolant loop 22. . As the battery cooling water flows from the downstream side of the battery radiator 43 to the upstream side of the second battery pump 45 through the second battery bypass conduit 47, the battery cooling water flows through the battery 41, the heater 42, and It is possible to bypass the battery chiller 37, and thus the battery cooling water passing through the second battery bypass conduit 47 is transferred to the battery radiator 43, the reservoir tank 48, and the water cooling system by the second battery pump 45. It may flow sequentially in the order of the second passage 72 of the heat exchanger 70.

The first battery bypass conduit 46 and the second battery bypass conduit 47 may be parallel to each other.

The battery cooling subsystem 12 may further include a second three-way valve 62 disposed at an inlet of the first battery bypass conduit 46 . That is, the second three-way valve 62 may be disposed at a joining point between the inlet of the first battery bypass conduit 46 and the battery cooling water loop 22 . When the second three-way valve 62 is switched to open the inlet of the first battery bypass conduit 46, some of the battery cooling water (battery cooling water flowing from the battery chiller 37) flows into the first battery bypass conduit ( 46), some of the battery cooling water can bypass the battery radiator 43, and the remaining battery cooling water (cooling water flowing out of the battery radiator 43) passes through the second battery bypass conduit 47. By flowing, the remaining battery cooling water may bypass the battery 41 , the heater 42 , and the battery chiller 37 . That is, when the inlet of the first battery bypass conduit 46 is opened by the switching of the second three-way valve 62, the battery coolant loop 22 connects the first battery bypass conduit 46 and the second battery by-pass. Independent circulation loops may be formed through the pass conduit 47 . The battery cooling water passing through the first battery bypass conduit 46 bypasses the second battery pump 45, the battery radiator 43, the reservoir tank 48, and the water-cooled heat exchanger 70, and By the operation of the pump 44, the battery 41, the heater 42, and the battery chiller 37 may be circulated in order. The battery cooling water passing through the second battery bypass conduit 47 bypasses the first battery pump 44, the battery 41, the heater 42, and the battery chiller 37, and the second battery pump 45 ), the battery radiator 43, the reservoir tank 48, and the water-cooled heat exchanger 70 may circulate in order.

When the second three-way valve 62 is switched to close the inlet of the first battery bypass conduit 46, the battery cooling water does not pass through the first battery bypass conduit 46. That is, when the inlet of the first battery bypass conduit 46 is closed by the switching of the second three-way valve 62, the battery cooling water may circulate along the battery cooling water loop 22.

The battery cooling subsystem 12 may be configured to be controlled by the battery management system 110 . The battery management system 110 may be configured to monitor the state of the battery 41 and perform cooling of the battery 41 when the temperature of the battery 41 becomes higher than a set temperature. The battery management system 110 may transmit a command instructing the cooling operation of the battery 41 to the controller 100, and thus the controller 100 controls the operation of the compressor 32 and the cooling operation of the expansion valve 17 on the chiller side. You can control the opening. When the operation of the air conditioning subsystem 11 is not required during the cooling operation of the battery 41, the controller 100 may control the closing of the cooling-side expansion valve 15. In addition, the battery management system 110 operates the first battery pump 44 and the second three so that the battery cooling water bypasses the battery radiator 43 and circulates through the battery 41 and the battery chiller 37 as necessary. Switching of the way valve 62 can be controlled.

The powertrain cooling subsystem 13 may be configured to cool the electric motor 51 and electric components 52 of the electric powertrain by the powertrain cooling water circulating through the powertrain cooling water loop 23 . The power train coolant loop 23 may be fluidly connected to the electric motor 51 , the electric component 52 , the power train radiator 53 , the power train pump 54 , and the reservoir tank 56 . In FIG. 1, the powertrain cooling water passes through the powertrain cooling water loop 23 through the electric motor 51, the powertrain radiator 53, the reservoir tank 56, the first passage 71 of the water-cooled heat exchanger 70, and the electric component 52 may flow in order.

The electric motor 51 may have a cooling water passage through which power train cooling water passes inside or outside thereof, and the power train cooling water loop 23 may be fluidly connected to the cooling water passage of the electric motor 51 .

The electrical component 52 may be one or more electrical components related to driving of the electric motor 51 such as an inverter, OBC, LDC, and the like. The electrical component 52 may have a cooling water passage through which power train cooling water passes inside or outside thereof, and the power train cooling water loop 23 may be fluidly connected to the cooling water passage of the electrical component 52 .

The power train radiator 53 may be disposed adjacent to the front grill of the vehicle, and the power train radiator 53 may be cooled by external air forcibly blown by the cooling fan 75 . The outer heat exchanger 35, the battery radiator 43, and the power train radiator 53 may be disposed adjacent to each other on the front side of the vehicle, and the cooling fan 75 may be installed in the outer heat exchanger 35 and the battery radiator 43. ), may be disposed on the rear side of the powertrain radiator 53.

The power train pump 54 may be disposed upstream of the electric motor 51 and the electric component 52, and the power train pump 54 may be configured to circulate the cooling water on the power train cooling water loop 23. there is.

The powertrain cooling subsystem 13 may further include a powertrain bypass conduit 55 to allow powertrain cooling water to bypass the powertrain radiator 53 . The powertrain bypass conduit 55 is discharged from the outlet of the electric motor 51 by directly connecting a point upstream of the powertrain radiator 53 and a point downstream of the powertrain radiator 53 on the powertrain coolant loop 23. The powertrain coolant may flow into the inlet of the powertrain pump 54 through the powertrain bypass conduit 55, and thus the powertrain coolant may bypass the powertrain radiator 53.

The inlet of the powertrain bypass conduit 55 may be connected to a point between the electric motor 51 and the powertrain radiator 53 on the powertrain coolant loop 23 . An outlet of the power train bypass conduit 55 may be connected to a point between the reservoir tank 56 and the electric component 52 on the power train cooling water loop 23 . Specifically, the outlet of the power train bypass conduit 55 may be connected to a point between the reservoir tank 56 and the inlet of the power train pump 54 on the power train coolant loop 23 .

The powertrain cooling subsystem 13 may further include a third three-way valve 63 disposed at an outlet of the powertrain bypass conduit 55, and the powertrain cooling water is discharged through the third three-way valve 63. The power train radiator 53 can be bypassed through the power train bypass conduit 55 by switching, and the power train cooling water is supplied to the electric motor 51 and the water-cooled heat exchanger 70 by the power train pump 54. can pass through the first passage 71 and the electric component 52 in sequence.

A reservoir tank 56 may be disposed downstream of the powertrain radiator 53 . In particular, the reservoir tank 56 may be disposed between the power train radiator 53 and the first passage 71 of the water-cooled heat exchanger 70 on the power train cooling water loop 23 .

The switching of the third three-way valve 63 of the power train cooling subsystem 13 and the operation of the power train pump 54 may be controlled by the controller 100 .

3 is a flowchart illustrating a charging control method of a vehicle battery according to an embodiment of the present invention.

The charger 130 starts charging or fast charging the battery 41 (S1). The charge controller 120 may determine an initial charging current of the charger 130 so that the SOC of the battery 41 becomes sufficient. When charging of the battery 41 starts, the temperature of the battery 41 rises, and thus the battery 41 may be cooled by the battery cooling subsystem 12 . As the charging time of the battery 41 elapses, the cooling of the battery 41 by the battery cooling subsystem 12 may reach a limit, and thus the battery 41 may be sufficiently cooled only by the battery cooling subsystem 12. can't In particular, when the battery 41 is rapidly charged, the temperature of the battery 41 may increase excessively. Accordingly, when the temperature of the battery 41 rises excessively, the charging current and the discharging current of the battery 41 may be restricted to a certain level, and thus the charging and discharging (output) of the battery 41 is limited to a relatively low level. It can be.

In addition, the controller 100 checks whether or not an external vehicle (camper, trailer, carrier, etc.) is fastened to the towing fastening structure provided at the rear of the electric vehicle (ie, towing fastening) through the towing controller 150 ( S2).

In step S2, when the controller 100 determines that towing is engaged, the controller 100 monitors the temperature Tb of the battery 41 through the battery management system 110 (S3). In the case of towing connection, a high power load is required for the electric vehicle, but the temperature (Tb) of the battery 41 rises excessively due to charging or rapid charging of the battery 41, so supply from the battery 41 to the electric motor power load can be relatively low. That is, when the temperature of the battery 41 rises excessively, the discharge (output) of the battery 41 may be limited, and thus the electric vehicle may not be able to sufficiently exhibit intended driving performance.

The controller 100 determines whether the temperature Tb of the battery 41 is equal to or greater than the limit temperature Th (S4). Here, the limit temperature (Th) may be a temperature obtained by subtracting a certain margin temperature (a) from the power limit temperature (Tr) (Th = Tr-a). The power limit temperature Tr is the temperature of the battery 41 at which the power output from the battery 41 to the electric motor is lowered below a set value, and when the temperature of the battery 41 reaches the power limit temperature Tr, The driving performance of the electric vehicle may be rapidly lowered below the set value. The margin temperature (a) may be a temperature set to secure time for controlling the temperature and charging current of the battery 41 before the temperature (Tb) of the battery 41 reaches the power limit temperature (Tr). . For example, the margin temperature (a) may be 0.5°C, 1°C, or 1.5°C.

In step S4, when the temperature Tb of the battery 41 is equal to or greater than the limit temperature Th, the charge controller 120 controls the battery 41 so that the temperature Tb of the battery 41 does not reach the power limit temperature Tr. ) Controls the charging current to the set first limit charging current according to the temperature (Tb) (S5). Specifically, the charge controller 120 may determine the first limit charging current so that the temperature Tb of the battery 41 does not reach the power limit temperature Tr. Since the temperature of the battery 41 is proportional to the charging current of the battery 41, the first limiting charging current may be a charging current determined to be relatively lower than the initial charging current set at the start of charging the battery 41.

After that, charging of the battery 41 is completed (S8).

In step S2, if it is determined that the towing is not performed by the controller 100, the controller 100 monitors the temperature Tb of the battery 41 through the battery management system 110 (S6).

The controller 100 controls the charging current according to the temperature Tb of the battery 41 to the set second limit charging current so that the temperature Tb of the battery 41 does not reach the high temperature limit temperature. Do (S7). The high temperature limit temperature may be a battery temperature high enough to damage the battery 41, and the high temperature limit temperature may be a temperature relatively higher than the power limit temperature Tr. Accordingly, when the temperature Tb of the battery 41 reaches the high temperature limit temperature, the battery 41 may be damaged due to the high temperature. The charge controller 120 may determine the second limiting charging current so that the temperature Tb of the battery 41 does not reach the high temperature limiting temperature. Since the temperature of the battery 41 is proportional to the charging current of the battery 41, the second limiting charging current may be a charging current determined to be relatively lower than the initial charging current set at the start of charging the battery 41. Also, the second limiting charging current may be a higher charging current than the first limiting charging current.

The above description is merely an example of the technical idea of the present invention, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the present invention.

Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed according to the claims below, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

11: air conditioning subsystem 12: battery cooling subsystem
13: power train cooling subsystem 15: cooling side expansion valve
16: heating side expansion valve 17: chiller side expansion valve
21: refrigerant loop 22: battery coolant loop
23: power train coolant loop 30: air conditioning case
31: evaporator 32: compressor
33: inner condenser 35: outer heat exchanger
36: branch conduit 37: battery chiller
38: accumulator 39: refrigerant bypass conduit
41: battery 42: heater
43: battery radiator 44: first battery pump
45: second battery pump 46: first battery bypass conduit
47: second battery bypass conduit 48: reservoir tank
51: electric motor 52: electrical parts
53: power train radiator 54: power train pump
55: power train bypass conduit 56: reservoir tank
61: first three-way valve 62: second three-way valve
63: third three-way valve 70: water-cooled heat exchanger
80: inverter 100: controller
110: battery management system 120: charge controller
130: charger 150: towing controller

Claims (6)

When the battery starts to charge, it determines whether the towing is fastened,
When towing is connected, it is judged whether the temperature of the battery is higher than the limit temperature,
Controlling the charging current for the battery to a first limit charging current so that the temperature of the battery does not reach the power limit temperature when the temperature of the battery is equal to or greater than the limit temperature;
The power limit temperature is a charging control method for a vehicle battery that is a temperature of a battery at which power output from the battery is lowered to a set value or less.
The method of claim 1,
The first limiting charging current is a charging current determined to be lower than the initial charging current set at the start of charging the battery.
The method of claim 1,
The limit temperature is a charging control method of a vehicle battery that is a temperature obtained by subtracting a certain margin temperature from the power limit temperature.
The method of claim 1,
If the toeing is not fastened, the battery or charging current is controlled to the second limiting charging current so that the temperature of the battery does not reach the high temperature limit temperature,
The high temperature limit temperature is a charging control method for a vehicle battery that is a temperature of a battery at a high temperature at which the battery may be damaged.
The method of claim 4,
The second limit charging current is a charging current determined to be lower than the initial charging current set at the start of charging the battery.
The method of claim 4,
The high temperature limit temperature is a charging control method of a vehicle battery at a temperature higher than the power limit temperature.

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