JP7574883B2 - Vehicle and method for charging the vehicle - Google Patents

Description

This disclosure relates to a vehicle and a method for charging the vehicle, and more specifically to a technology for charging an on-board power storage device with power supplied via a charging cable from a charging facility external to the vehicle.

In recent years, there has been progress in the development of electric vehicles that are configured to enable "plug-in charging," in which an on-board power storage device is charged with power supplied via a charging cable from a charging facility outside the vehicle (such as a charging station). With plug-in charging, heat loss generally occurs in the charging facility, the charging cable, and the charging inlet of the vehicle. For this reason, technologies have been proposed to protect these components from excessive temperature increases.

For example, the power supply device of a vehicle disclosed in JP 2015-233366 A (Patent Document 1) receives information from outside the vehicle indicating whether the temperature of the charging equipment outside the vehicle (power supply device in Patent Document 1) or the charging cable is at risk of exceeding the heat-resistant temperature. If there is a risk that the temperature of the power supply device or the charging cable will exceed the heat-resistant temperature, the power supply device limits the charging power of the on-board charger.

JP 2015-233366 A

In plug-in charging, heat loss (Joule heat) occurs at the contact point between the connector at the end of the charging cable and the inlet on the vehicle side (hereinafter referred to as the "contact point"), and there is particular concern that the temperature at the contact point will rise excessively. At the same time, there is also a desire to shorten the charging time to improve user convenience. Reducing the charging time is achieved by increasing the charging power. However, increasing the charging power (more specifically, the current supplied from the charging equipment) increases the heat loss at the contact point accordingly, making overheating of the contact point even more of a concern. Therefore, there is a need to shorten the charging time as much as possible while adequately protecting the charging cable and inlet.

From this perspective, when the charging equipment and the charging cable are configured as an integrated unit, it is possible to provide a cooling mechanism in the charging equipment and the charging cable (hereinafter collectively referred to as "charging equipment"). More specifically, the connector and inlet of the charging cable can be cooled by a cooling mechanism (a so-called water-cooled cooling mechanism) in which a coolant circulates between the charging equipment and the connector of the charging cable. As a result, it is possible to prevent overheating of the contact area and to adequately protect the charging cable and inlet.

The inventors have noticed that the following problems may arise when a cooling mechanism is installed in this way. That is, the market will include a mixture of charging equipment equipped with a cooling mechanism and charging equipment not equipped with a cooling mechanism. If the charging mode of the power storage device is made uniform regardless of whether the charging equipment is equipped with a cooling mechanism or not, if the charging mode is determined based on the charging equipment not equipped with a cooling mechanism, the charging power of the charging equipment equipped with a cooling mechanism will be relatively small, and the charging time may not be sufficiently shortened. On the other hand, if the charging mode is determined based on the charging equipment equipped with a cooling mechanism, the charging power of the charging equipment not equipped with a cooling mechanism will be excessively large, and the charging equipment may not be sufficiently protected. Therefore, it is desirable to change the charging mode of the power storage device depending on whether the charging equipment is equipped with a cooling mechanism or not.

The present disclosure has been made to solve the above problems, and its purpose is to shorten the charging time as much as possible during plug-in charging while adequately protecting the charging cable and inlet.

(1) A vehicle according to an aspect of the present disclosure is configured to enable plug-in charging, in which an on-board power storage device is charged with power supplied from a charging facility outside the vehicle via a charging cable. The vehicle includes an inlet configured to receive a connector of the charging cable, and a control device that controls the supply current from the charging facility so that it does not exceed a maximum allowable current. The control device acquires information related to whether or not a cooling mechanism for cooling the connector and inlet is provided in the charging facility (hereinafter also referred to as "related information"). When a cooling mechanism is provided in the charging facility, the control device increases the maximum allowable current, which is the maximum value of the current that the connector and inlet can tolerate, compared to when a cooling mechanism is not provided in the charging facility.

(2) Preferably, the related information is information that associates information for identifying a charging facility with information indicating whether the identified charging facility is provided with a cooling mechanism.

According to the configurations (1) and (2) above, when a cooling mechanism is provided in the charging equipment, the maximum allowable current is set to be larger than when a cooling mechanism is not provided in the charging equipment. As a result, in a charging equipment provided with a cooling mechanism, a relatively large maximum allowable current can be set to shorten the charging time. On the other hand, in a charging equipment in which a cooling mechanism is not provided at a charging stand, the maximum allowable current can be limited to a relatively small value, thereby ensuring that the charging cable and inlet are protected. Therefore, the charging time can be shortened as much as possible while adequately protecting the charging cable and inlet.

(3) Preferably, the vehicle further includes a memory in which the relevant information is stored. The control device acquires the relevant information by referring to the memory.

According to the above configuration (3), the related information can be obtained by referring to the memory, which, for example, makes it unnecessary to communicate with the outside of the vehicle to obtain the related information.

(4) Preferably, the vehicle further includes a communication device configured to be capable of communicating with at least one of another vehicle and a server provided outside the vehicle. The control device acquires the related information through communication using the communication device.

According to the configuration (4) above, even if the related information stored in the memory does not include information about the charging equipment, related information can be obtained from other external vehicles or servers.

(5) Preferably, the vehicle further includes a location information acquisition device configured to acquire location information of the vehicle. The control device identifies the charging equipment by acquiring location information of the vehicle when the vehicle and the charging equipment are connected by a charging cable.

(6) Preferably, the control device identifies the charging equipment by acquiring at least one of identification information of the charging equipment and information indicating the model of the charging equipment through communication with the charging equipment via the charging cable.

According to the configuration of (5) above, when the vehicle and the charging equipment are connected by a charging cable, the vehicle's position and the position information of the charging equipment are approximately equal, so the charging equipment can be identified by the vehicle's position information. Alternatively, as in the configuration of (6) above, it is also possible to identify the charging equipment by at least one of the identification information of the charging equipment and the information indicating the model of the charging equipment.

(7) A vehicle charging method according to an aspect of the present disclosure plugs in and charges an on-board power storage device with power supplied from a charging facility outside the vehicle via a charging cable. The vehicle includes an inlet configured to receive a connector of the charging cable. The vehicle charging method includes first to third steps. The first step is a step of acquiring information (related information) related to whether or not a cooling mechanism for cooling the connector and inlet is provided in the charging facility. The second step is a step of determining whether or not a cooling mechanism is provided in the charging facility based on the related information. The third step is a step of setting a maximum current that can be tolerated by the connector and inlet to a value larger when the charging facility is provided with a cooling mechanism than when the charging facility is not provided with a cooling mechanism.

According to the method (7) above, similar to the configuration (1) above, it is possible to shorten the charging time as much as possible while adequately protecting the charging cable and inlet.

According to the present disclosure, it is possible to minimize charging time during plug-in charging while adequately protecting the charging cable and inlet.

1 is a diagram illustrating a schematic overall configuration of a charging system according to a first embodiment of the present disclosure. 1 is a block diagram showing a schematic configuration of a vehicle, a charging stand, and a charging cable according to a first embodiment. 5 is a flowchart showing plug-in charging control in the first embodiment. FIG. 4 is a diagram showing an example of a charging table in the first embodiment. FIG. 11 is a diagram illustrating an example of charger information stored in a charger information database of the server. FIG. 13 is a diagram showing an example of two maps. 10 is a flowchart showing plug-in charging control in the second embodiment. FIG. 11 is a diagram showing an example of a charging table in the second embodiment.

The following describes in detail the embodiments of the present disclosure with reference to the drawings. Note that the same or corresponding parts in the drawings are given the same reference numerals and their description will not be repeated.

[First embodiment]
<Overall configuration of charging system>
1 is a diagram illustrating a schematic overall configuration of a charging system according to a first embodiment of the present disclosure. Referring to FIG 1, a charging system 10 includes a vehicle 1, a charging stand 2, a charging cable 3, and a server 9.

Vehicle 1 and charging station 2 are configured to be electrically connected by charging cable 3. Vehicle 1 is a vehicle of a certain user (not shown), and is, for example, a plug-in hybrid vehicle. However, vehicle 1 may also be an electric vehicle as long as it is configured to be plug-in charged.

Figure 1 illustrates a situation in which plug-in charging is performed on vehicle 1 by charging stand 2. Charging stand 2 is, for example, a public charging stand (or charging station). Therefore, plug-in charging by charging stand 2 may also be performed on a vehicle (not shown) other than vehicle 1. Also, plug-in charging of vehicle 1 may also be performed by a charging stand (not shown) other than charging stand 2 illustrated in Figure 1.

The vehicle 1 and the server 9 are configured to be able to wirelessly communicate with each other (two-way communication). Although not shown, wireless communication is also possible between other vehicles (not shown) and the server 9.

The server 9 includes a CPU (Central Processing Unit), a memory, and an input/output port, none of which are shown in the figure. A part or all of the server 9 may be configured to execute arithmetic processing by software, or may be configured to execute arithmetic processing by hardware such as electronic circuits. The server 9 includes a charger information database 91 that stores information (charger information INFO) about a large number of charging stations, including the charging station 2 shown in FIG. 1. Details of the charger information INFO will be described later (see FIG. 5).

Fig. 2 is a block diagram showing a schematic configuration of a vehicle 1, a charging stand 2, and a charging cable 3 according to the first embodiment. Referring to Fig. 2, the charging stand 2 is, for example, a charger for direct current (DC) charging, and converts AC power from a system power supply 500 into DC power for charging a battery 150 mounted on the vehicle 1 and supplies the converted power. The charging stand 2 includes a power line ACL, an AC/DC converter 210, a voltage sensor 220, power feed lines PL0 and NL0, a cooling mechanism 230, and a control circuit 200. The cooling mechanism 230 includes a flow path 231, a water pump 232, and a heat exchanger 233.

The power line ACL is electrically connected to the system power supply 500. The power line ACL transmits AC power from the system power supply 500 to the AC/DC converter 210.

The AC/DC converter 210 converts the AC power on the power line ACL into DC power for charging the battery 150 mounted on the vehicle 1. The power conversion by the AC/DC converter 210 may be performed by a combination of AC/DC conversion for power factor correction and DC/DC conversion for voltage level adjustment. The DC power output from the AC/DC converter 210 is supplied by the positive power supply line PL0 and the negative power supply line NL0.

The voltage sensor 220 is provided between the power supply lines PL0 and NL0. The voltage sensor 220 detects the voltage between the power supply lines PL0 and NL0 and outputs the detection result to the control circuit 200.

The water pump 232, in accordance with a command from the control circuit 200, circulates the cooling liquid (cooling water) sealed in the circulation path 231 between the heat exchanger 233 and the connector 310 of the charging cable 3. This makes it possible to cool the contact area (area where the terminals contact each other) between the connector 310 and the inlet 110.

The heat exchanger 233 is configured to include, for example, a heat transfer tube and heat dissipation fins (not shown). In the heat exchanger 233, the heat of the cooling liquid in the flow path 231 is dissipated to the surrounding outside air.

The configuration of the cooling mechanism 230 is not limited to the water-cooled configuration described above, and may be, for example, an air-cooled type. Alternatively, a heat pump system or a thermoelectric cooling system including a Peltier element may be used as the cooling mechanism.

The control circuit 200 includes a CPU, a memory, and an input/output port (none of which are shown). The control circuit 200 controls the power conversion operation of the AC/DC converter 210 based on the voltage detected by the voltage sensor 220, various switches, signals from the vehicle 1, and maps and programs stored in the memory. The control circuit 200 also controls the cooling operation of the water pump 232 based on various signals and programs stored in the memory.

Furthermore, the connector 310 of the charging cable 3 is provided with a temperature sensor 319 that detects a temperature T2 of the connector 310. By receiving a signal indicating the temperature T2 from the temperature sensor 319, the control circuit 200 can diagnose whether there is an abnormality in the connector 310 (more specifically, overheating of the contact portion between the connector 310 and the inlet 110).

The vehicle 1 includes an inlet 110, charging lines PL1 and NL1, a voltage sensor 121, a current sensor 122, vehicle contactors 131 and 132, system main relays 141 and 142, a battery 150, power lines PL2 and NL2, a PCU (Power Control Unit) 160, an engine 170, motor generators 171 and 172, a power split device 173, drive wheels 174, a communication module 180, and an ECU (Electronic Control Unit) 100.

The inlet (also called a charging port) 110 is configured to be electrically connectable to the connector 310 of the charging cable 3. More specifically, the connector 310 is inserted into the inlet 110 with a mechanical connection such as fitting, thereby ensuring an electrical connection between the power supply line PL0 and the positive contact of the inlet 110, and also ensuring an electrical connection between the power supply line NL0 and the negative contact of the inlet 110. In addition, by connecting the inlet 110 and the connector 310 with a charging cable, the ECU 100 of the vehicle 1 and the control circuit 200 of the charging stand 2 can mutually transmit and receive various signals, commands, and information (data) by communication according to a predetermined communication standard such as CAN (Controller Area Network) or communication by analog signals via an analog control line.

The inlet 110 is also provided with a temperature sensor 119 for detecting the temperature T1 of the inlet 110, similar to the connector 310 of the charging cable 3. By receiving a signal indicating the temperature T1 from the temperature sensor 119, the ECU 100 can diagnose whether or not there is an abnormality, such as overheating, in the inlet 110.

The voltage sensor 121 is provided between the charging line PL1 and the charging line NL1, closer to the inlet 110 than the vehicle contactors 131, 132. The voltage sensor 121 detects the DC voltage between the charging lines PL1, NL1, and outputs the detection result to the ECU 100. The current sensor 122 is provided in the charging line PL1. The current sensor 122 detects the current flowing through the charging line PL1, and outputs the detection result to the ECU 100. The ECU 100 can calculate the power supplied from the charging stand 2 based on the detection results from the voltage sensor 121 and the current sensor 122.

The vehicle contactor 131 is connected to the charging line PL1, and the vehicle contactor 132 is connected to the charging line NL1. The closing/opening of the vehicle contactors 131, 132 is controlled in response to commands from the ECU 100. When the vehicle contactors 131, 132 are closed and the system main relays 141, 142 are closed, power transmission between the inlet 110 and the battery 150 is enabled.

Battery 150 supplies electric power to generate a driving force for vehicle 1. Battery 150 also stores electric power generated by motor generators 171, 172. Battery 150 is a battery pack including a plurality of cells (not shown), each of which is a secondary battery such as a lithium ion secondary battery or a nickel-hydrogen secondary battery. In this embodiment, the internal configuration of the battery pack is not particularly limited, so hereinafter, the cells will not be mentioned in particular and will simply be referred to as battery 150. Battery 150 may be a capacitor such as an electric double layer capacitor. Battery 150 corresponds to the "electricity storage device" according to the present disclosure.

The positive electrode of the battery 150 is electrically connected to a node ND1 via a system main relay 141. The node ND1 is electrically connected to a charging line PL1 and a power line PL2. Similarly, the negative electrode of the battery 150 is electrically connected to a node ND2 via a system main relay 142. The node ND2 is electrically connected to a charging line NL1 and a power line NL2. The closing/opening of the system main relays 141 and 142 is controlled in response to a command from the ECU 100.

Battery 150 is provided with a voltage sensor 151, a current sensor 152, and a temperature sensor 153. Voltage sensor 151 detects the voltage VB of battery 150. Current sensor 152 detects the current IB input to and output from battery 150. Temperature sensor 153 detects the temperature TB of battery 150. Each sensor outputs its detection result to ECU 100. ECU 100 can estimate, for example, the SOC (State Of Charge) of battery 150 based on the detection results of each sensor.

The PCU 160 is electrically connected between the power lines PL2, NL2 and the motor generators 171, 172. The PCU 160 includes a converter and an inverter (not shown), and performs bidirectional power conversion between the battery 150 and the motor generators 171, 172 when the system main relays 141, 142 are closed.

The engine 170 is an internal combustion engine such as a gasoline engine, and generates driving force for the vehicle 1 to run in response to a control signal from the ECU 300.

Each of the motor generators 171, 172 is, for example, a three-phase AC rotating electric machine. The motor generator 171 is connected to the crankshaft of the engine 170 via a power split device 173. When starting the engine 170, the motor generator 171 rotates the crankshaft of the engine 170 using the power of the battery 150. The motor generator 171 can also generate power using the power of the engine 170. The AC power generated by the motor generator 171 is converted to DC power by the PCU 160 and charged into the battery 150. The AC power generated by the motor generator 171 may also be supplied to the motor generator 172.

The motor generator 172 rotates the drive shaft using at least one of the power from the battery 150 and the power generated by the motor generator 171. The motor generator 172 can also generate power through regenerative braking. The AC power generated by the motor generator 172 is converted to DC power by the PCU 160 and charged into the battery 150.

The power split device 173 is, for example, a planetary gear mechanism, and mechanically connects three elements: the crankshaft of the engine 170, the rotating shaft of the motor generator 171, and the drive shaft.

The communication module 180 is a digital communication module (DCM) configured to enable wireless communication with the server 9. The communication module 180 corresponds to the "communication device" according to the present disclosure.

The navigation device 190 includes a Global Positioning System (GPS) receiver 191 that identifies the position of the vehicle 1 based on radio waves from an artificial satellite (not shown). The navigation device 190 executes various navigation processes for the vehicle 1 using the position information (GPS information) of the vehicle 1 identified by the GPS receiver 191. More specifically, the navigation device 190 calculates a recommended route from the current location of the vehicle 1 to the destination based on the GPS information of the vehicle 1 and road map data stored in a memory (not shown), and outputs information on the calculated recommended route to the ECU 100.

Like the control circuit 200, the ECU 100 is configured to include a CPU 101, memory 102 such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and an input/output port (not shown). The ECU 100 controls the devices in response to signals from the various sensors, etc., so that the vehicle 1 is in a desired state.

The main control executed by the ECU 100 is plug-in charging control, which charges the on-board battery 150 with power supplied from the charging stand 2. The plug-in charging control is carried out by transmitting and receiving signals, commands, and information between the ECU 100 of the vehicle 1 and the control circuit 200 of the charging stand 2 via the charging cable 3. In the plug-in charging control, the power conversion operation by the AC/DC converter 210 is controlled so that the current supplied from the charging stand 2 to the vehicle 1 via the charging cable 3 does not exceed the "maximum allowable current", which is the maximum allowable value of that current.

The memory 102 of the ECU 100 also stores a charging table TBL1 used for plug-in charging control. The charging table TBL1 will be described later (see FIG. 4).

<Protecting charging devices and reducing charging times>
In plug-in charging, it is desirable to shorten the charging time in order to improve user convenience. The charging time can be shortened by increasing the charging power supplied from the charging station. However, during plug-in charging, at the contact portion between the connector of the charging cable and the inlet on the vehicle side (the contact point between the connector terminal and the inlet terminal), Joule heat is generated as heat loss, the magnitude of which is calculated by multiplying the resistance value of the contact portion by the square of the current value. Therefore, if the supply current from the charging station is increased in order to increase the charging power, the heat loss also increases accordingly, and overheating of the contact portion becomes even more of a concern. Therefore, it is desirable to shorten the charging time as much as possible while appropriately protecting the connector and inlet of the charging cable.

On the market, there are charging stands equipped with the cooling mechanism 230 (circulation path 231, water pump 232, and heat exchanger 233) as shown in FIG. 2, while there are also charging stands (not shown) that are not equipped with the cooling mechanism 230. In this way, in a market environment where various charging stands are mixed, if the charging mode of the battery 150 is made uniform regardless of whether the cooling mechanism 230 is installed in the charging stand, if the charging mode is determined based on the charging stand that is not equipped with the cooling mechanism 230, the charging power of the charging stand equipped with the cooling mechanism 230 will be relatively small, and it may not be possible to sufficiently shorten the charging time. On the other hand, if the charging mode is determined based on the charging stand equipped with the cooling mechanism 230, the charging power of the charging stand that is not equipped with the cooling mechanism 230 will be excessively large, and it may not be possible to sufficiently protect the connector and inlet of the charging cable.

Therefore, in this embodiment, the charging mode of the battery 150 is changed depending on whether or not the cooling mechanism 230 is provided at the charging stand. More specifically, when the cooling mechanism 230 is provided at the charging stand, the maximum allowable current (maximum allowable currents I and J described below) is set to be larger than when the cooling mechanism 230 is not provided at the charging stand. As a result, in a charging stand that is provided with the cooling mechanism 230 and has high cooling performance, a relatively large maximum allowable current can be set to shorten the charging time. On the other hand, in a charging stand that is not provided with the cooling mechanism 230 and has relatively low cooling performance, the maximum allowable current is limited to a relatively small value, thereby ensuring protection of the charging cable and inlet. The plug-in charging control in the first embodiment will be described in detail below.

<Plug-in charging flow>
Fig. 3 is a flowchart showing plug-in charging control in embodiment 1. The flowcharts shown in Fig. 3 and Fig. 7 described later are executed when the connector 310 of the charging cable 3 is inserted into the inlet 110. Each step (hereinafter abbreviated as "S") included in the flowchart shown in Fig. 4 is basically realized by software processing by the ECU 100, but may also be realized by dedicated hardware (electrical circuitry) created within the ECU 100.

Referring to FIG. 3, in S110, the ECU 100 acquires the temperature TB of the battery 150 from the temperature sensor 153 and estimates the SOC of the battery 150. As a method for estimating the SOC, various known methods can be adopted, such as a method of referring to a previously acquired SOC-OCV (Open Circuit Voltage) curve or a current integration method.

In S120, the ECU 100 acquires GPS information of the vehicle 1 from the navigation device 190. Note that since the vehicle 1 and the charging station (charging station 2 in the example shown in FIG. 2) are adjacent to each other and connected to each other by the charging cable 3, the position of the vehicle 1 and the position of the charging station can be considered to be approximately the same.

At S130, the ECU 100 refers to the charging table TBL1 stored in the memory 102 to determine whether the location information of the charging station (=GPS information of the vehicle 1) is included in the charging table TBL1.

FIG. 4 is a diagram showing an example of the charging table TBL1 in the first embodiment. As shown in FIG. 4, the charging table TBL1 associates location information about the installation locations of various charging stations where plug-in charging of the vehicle 1 has been performed in the past with information about whether or not the charging station had a cooling mechanism 230. Therefore, by referring to the charging table TBL1, it is possible to determine the presence or absence of the cooling mechanism 230 at a charging station (hereinafter also referred to as a "target charging station") connected to the vehicle 1 via a charging cable from the location information of the target charging station. Note that the charging table TBL1 corresponds to "related information" according to the present disclosure.

Returning to FIG. 3, if the location information of the target charging station is included in the charging table TBL1 (YES in S130), the ECU 100 proceeds to S140. On the other hand, if the location information of the target charging station is not included in the charging table TBL1 (NO in S130), the ECU 100 transmits the location information of the target charging station to the server 9, thereby acquiring information from the server 9 as to whether the target charging station includes a cooling mechanism 230 (S135).

Figure 5 is a diagram showing an example of charger information INFO stored in charger information database 91 of server 9. Referring to Figure 5, in the charger information INFO, for example, a charger ID which is identification information of the charging stand, information on the installation location of the charging stand (location information), information on the charging standard supported by the charging stand, information on the charging fee of the charging stand, and information on whether the charging stand has a cooling mechanism 230 are associated with each other. When the server 9 receives the location information of the target charging stand together with an inquiry from ECU 100 of vehicle 1, it refers to the charger information INFO and responds to ECU 100 as to whether the target charging stand has a cooling mechanism 230.

Referring again to FIG. 3, in S140, ECU 100 determines whether the target charging station has a cooling mechanism 230. More specifically, if the determination in S130 is YES, ECU 100 refers to charging table TBL1 and determines whether the target charging station has a cooling mechanism 230 based on the past charging history at the target charging station. On the other hand, if the determination in S130 is NO, ECU 100 determines whether the target charging station has a cooling mechanism 230 based on the response from server 9.

If the target charging station has a cooling mechanism 230 (YES in S140), the ECU 100 calculates the maximum allowable current I of the battery 150 by referring to map MP1 described below (S150). On the other hand, if the target charging station does not have a cooling mechanism 230 (NO in S140), the ECU 100 calculates the maximum allowable current J of the battery 150 by referring to map MP2 (S155).

Note that the charger information INFO of the server 9 does not necessarily include information about all charging stations, so it is possible that the charger information INFO does not include information about the target charging station. In such a case, the server 9 sends a response to the ECU 100 indicating that there is no information about the target charging station. In this case, the ECU 100 prioritizes protection of the inlet 110, etc., and proceeds to S155 assuming that the target charging station does not have a cooling mechanism 230, and refers to map MP2.

6 is a diagram showing an example of maps MP1 and MP2. As shown in FIG. 6, map MP1 is a three-dimensional map including three parameters, for example, temperature TB of battery 150, SOC of battery 150, and maximum allowable current I. More specifically, temperature TB of battery 150 is divided into a plurality of temperature regions (indicated by T1, T2, ...) each having a predetermined width. Similarly, SOC of battery 150 is divided into a plurality of SOC regions (indicated by S1, S2, ...) each having a predetermined width. Maximum allowable current I is determined for each combination of the divided temperature region and SOC region. In FIG. 6, maximum allowable current I (m, n) corresponding to the combination of temperature region Tm and SOC region Sn is shown. Although detailed description will not be repeated, in map MP2, as in map MP1, maximum allowable current J is determined for each combination of temperature region and SOC region.

When compared under the same temperature and SOC conditions (same combination of temperature region Tm and SOC region Sn), the absolute value of the maximum allowable current I(m,n) in map MP1 is greater than the absolute value of the maximum allowable current J(m,n) in map MP2 (|I(m,n)|>|J(m,n)|).

Note that the reason why each map MP1, MP2 includes the temperature TB and SOC of the battery 150 is that, like a typical secondary battery, the charging capacity of the battery 150 (the amount of current that the battery 150 can accept) has temperature and SOC dependencies. However, it is not essential that the maps MP1, MP2 are three-dimensional maps including the temperature TB and SOC, and the maps MP1, MP2 may be two-dimensional maps including either the temperature TB or the SOC and the maximum allowable current. Alternatively, without taking the charging capacity of the battery 150 into particular consideration, only a predetermined value of the maximum allowable current may be stored in the memory 102 instead of the maps MP1, MP2.

Returning to FIG. 3, the ECU 100 then controls the charging stand 2 to start plug-in charging of the battery 150 (S160). In detail, the ECU 100 transmits a command to start plug-in charging to the control circuit 200 of the target charging stand via the charging cable 3, thereby causing the control circuit 200 to control the AC/DC converter 210 to start power supply.

The ECU 100 continues the power supply until the plug-in charging completion condition is met (NO in S170), and when the plug-in charging completion condition is met (YES in S170), the ECU 100 stops the power supply (S180). Note that the plug-in charging completion condition may be met when the SOC of the battery 150 reaches a specified value and the battery 150 is fully charged, or when a predetermined charging end time has arrived in so-called timer charging.

The ECU 100 updates the charging table TBL1, for example, after the power supply is stopped (S190). In detail, when the ECU 100 determines whether or not the target charging station has a cooling mechanism 230 based on the response from the server 9 (S135), the ECU 100 adds information about the target charging station to the charging table TBL1. Although not shown, when information about the target charging station is already included in the charging table TBL1 (YES determination in S130), the process of S190 is skipped. Note that the timing of execution of the process of S190 is not particularly limited, and may be any timing after the process of S140.

As described above, according to the first embodiment, when the cooling mechanism 230 is provided at the target charging station, the maximum allowable current I is set (S150). On the other hand, when the cooling mechanism 230 is not provided at the target charging station, the maximum allowable current J is set (S155). Under the same temperature conditions and the same SOC conditions, the maximum allowable current I (absolute value) is greater than the maximum allowable current J (absolute value). As a result, in a charging station (see FIG. 2) where the cooling mechanism 230 is provided, a relatively large maximum allowable current I is set, so that the charging time can be shortened. On the other hand, in a charging station (not shown) where the cooling mechanism 230 is not provided, a relatively small maximum allowable current J is set to limit the supply current, so that the heat loss at the connection part between the connector 310 of the charging cable 3 and the inlet 110 of the vehicle 1 is reduced, and the connection part can be protected more reliably. Therefore, according to the first embodiment, appropriate measures can be taken for shortening the charging time and protecting the charging cable 3 and the vehicle 1 depending on the presence or absence of the cooling mechanism 230 at the target charging station.

In the flowchart shown in FIG. 3, the server 9 is queried as to whether or not the target charging station has a cooling mechanism 230 in the process of S135. However, this inquiry may be made to vehicles (not shown) around the vehicle 1 by so-called vehicle-to-vehicle communication. For example, a response to the inquiry may be obtained from another vehicle that has completed plug-in charging at the target charging station.

[Embodiment 2]
In the first embodiment, a configuration has been described as an example in which the position of a target charging station is identified using GPS information of vehicle 1, and the maximum allowable current is switched based on the position information of the charging station. However, it is not essential to use the position information of the target charging station to identify the target charging station. In the second embodiment, a configuration in which the maximum allowable current is set through communication between vehicle 1 and the target charging station will be described. In the second embodiment, a charging table TBL2 different from charging table TBL1 is stored in memory 102 of ECU 100. Other configurations of the target charging station and the vehicle in the second embodiment are basically the same as those shown in FIG. 2 , and therefore description will not be repeated.

Figure 7 is a flowchart showing plug-in charging control in embodiment 2. Referring to Figure 7, this flowchart differs from the flowchart in embodiment 1 (see Figure 3) in that it includes processes of S220 to S235 instead of processes of S120 to S135.

Referring to FIG. 7, the ECU 100 acquires the temperature TB of the battery 150 from the temperature sensor 153 and estimates the SOC of the battery 150 (S210). After that, the ECU 100 acquires the charger ID of the target charging station by communicating with the target charging station via the charging cable 3 (S220). Then, the ECU 100 determines whether the charger ID of the target charging station is included in the charging table TBL2 (S230).

Figure 8 is a diagram showing an example of the charging table TBL2 in the second embodiment. As shown in Figure 8, the charging table TBL2 includes information regarding the charger ID, the model of the charging station, and the presence or absence of the cooling mechanism 230 for various charging stations that have been used for plug-in charging of the vehicle 1. Therefore, the ECU 100 can determine the presence or absence of the cooling mechanism 230 from the charger ID.

Whether or not the cooling mechanism 230 is provided depends on the model (model number) of the charging station. Therefore, the ECU 100 may acquire information about the model of the target charging station via communication instead of or in addition to the charger ID of the target charging station, and determine whether or not the cooling mechanism 230 is provided from the acquired information.

Referring again to FIG. 7, in S230, the ECU 100 refers to the charging table TBL2 stored in the memory 102 and determines whether information related to the charger ID (or the model of the target charging station) is included in the charging table TBL2.

If the information on the charger ID of the target charging station is not included in the charging table TBL2 (NO in S230), the ECU 100 transmits the charger ID to the server 9 to use the charger information INFO shown in FIG. 5, and obtains from the server 9 a response as to whether the target charging station includes the cooling mechanism 230 (S235). If the information on the charger ID of the target charging station is included in the charging table TBL2 (YES in S230), the process of S235 is skipped and the process proceeds to S240. Each process from S240 onwards is equivalent to the corresponding process in the flowchart in the first embodiment (see FIG. 3), and therefore detailed description will not be repeated.

As described above, according to the second embodiment, it is determined whether or not the target charging stand is provided with the cooling mechanism 230 based on the charger ID (or information related to the model) of the target charging stand. If the cooling mechanism 230 is provided, the maximum allowable current I is set (S250), whereas if the target charging stand is not provided with the cooling mechanism 230, the maximum allowable current J is set (S255). In this way, by using the charger ID (or information related to the model), it is possible to shorten the charging time as much as possible while appropriately protecting the connector 310 and inlet 110 of the charging cable 3, as in the first embodiment.

The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is indicated by the claims rather than the description of the embodiments above, and is intended to include all modifications within the meaning and scope of the claims.

10 Charging system, 1 Vehicle, 2 Charging station, 3 Charging cable, 9 Server, 91 Charger information database, 100 ECU, 101 CPU, 102 Memory, 110 Inlet, 119, 153, 319 Temperature sensor, 121, 151, 220 Voltage sensor, 122, 152 Current sensor, 131, 132 Vehicle contactor, 141, 142 SMR, 150 Battery, 160 PCU, 170 Engine, 171, 172 Motor generator, 173 Power split device, 174 Drive wheel, 180 Communication module, 190 Navigation device, 191 GPS receiver, 200 Control circuit, 210 AC/DC converter, 230 Cooling mechanism, 231 Distribution path, 232 Water pump, 233 Heat exchanger, 310 Connector, 500 System power supply.

Claims (8)

A vehicle configured to enable plug-in charging in which an on-board power storage device is charged with electric power supplied from a charging facility external to the vehicle via a charging cable,
an inlet configured to receive a connector of the charging cable;
A control device for controlling a supply current from the charging facility,
The control device, when a cooling mechanism for cooling the connector and the inlet is provided in the charging equipment, increases the supply current compared to when the cooling mechanism is not provided in the charging equipment. The vehicle according to claim 1, wherein the control device acquires information regarding whether the cooling mechanism is provided in the charging equipment, and increases the supply current based on the acquired information. The vehicle according to claim 2, wherein the control device increases the maximum value of the supply current when the cooling mechanism is provided in the charging facility compared to when the cooling mechanism is not provided in the charging facility. The control device includes:
determining whether the cooling mechanism is provided in the charging facility based on location information of the charging facility;
The vehicle according to any one of claims 1 to 3, wherein, when it is not possible to determine whether or not the cooling mechanism is provided in the charging equipment from the location information of the charging equipment, information indicating whether or not the cooling mechanism is provided in the charging equipment is obtained from the server by transmitting the location information of the charging equipment to the server. A vehicle charging method for plugging in an on-board power storage device using power supplied from a charging facility external to the vehicle via a charging cable, comprising:
the vehicle includes an inlet configured to receive a connector of the charging cable;
The vehicle charging method includes a step of increasing the current supplied from the charging equipment to the vehicle by control by the vehicle when a cooling mechanism for cooling the connector and the inlet is provided in the charging equipment, compared to a case in which the cooling mechanism is not provided in the charging equipment. 6. The vehicle charging method according to claim 5, wherein the step of increasing the supply current includes a step of the vehicle acquiring information regarding whether the cooling mechanism is provided in the charging equipment, and increasing the supply current based on the acquired information . 7. The vehicle charging method according to claim 6, wherein the step of increasing the supply current includes a step of increasing a maximum value of the supply current when the cooling mechanism is provided in the charging equipment, compared to a case where the cooling mechanism is not provided in the charging equipment . determining, by the vehicle, whether or not the cooling mechanism is provided in the charging facility based on location information of the charging facility;
The vehicle charging method according to any one of claims 5 to 7, further comprising: when it is not possible to determine whether or not the cooling mechanism is provided in the charging facility from the location information of the charging facility, the vehicle acquires information indicating whether or not the cooling mechanism is provided in the charging facility from the server by transmitting location information of the charging facility from the vehicle to a server.

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