BACKGROUND OF THE INVENTION

1. Field of the Invention

[0001] The invention relates to a vehicle and a control method for the vehicle. More specifically, the invention relates to an abnormality logging function in a vehicle capable of charging by using electric power from an external power supply transmitted via a charging cable.

2. Description of Related Art

[0002] In recent years, as an environment-friendly vehicle, attention is focused on a vehicle that has a power storage device (e.g., a secondary battery or a capacitor) mounted thereon and is driven by using a driving force generated from electric power stored in the power storage device. Examples of such vehicle include an electric vehicle, a hybrid vehicle, and a fuel cell vehicle. In addition, there is proposed a technology in which the power storage device mounted on these vehicles is charged by using a commercial power supply having high power generation efficiency.

[0003] In the field of the hybrid vehicle as well, similarly to the electric vehicle, there is available a vehicle capable of charging (hereinafter also simply referred to as "external charging") of the vehicle-mounted power storage device by using a power supply outside the vehicle (hereinafter also simply referred to as an "external power supply"). For example, there is available a so-called "plug-in hybrid vehicle" capable of charging of the power storage device by using a power supply in an ordinary house by connecting an outlet provided in the house and a charge inlet (hereinafter also referred to as an "inlet") provided in the vehicle with' a charging cable. With this arrangement, the fuel consumption efficiency of the hybrid vehicle is expected to be enhanced.

[0004] Japanese Patent Publication No. 3135040 discloses the configuration of a charging connecter for connecting a charging cable used in external charging of a vehicle to an inlet of the vehicle. According to the charging connector disclosed in Japanese Patent Publication No. 3135040, an operation for fitting the connector and a switch operation for energization can be simultaneously performed.

[0005] In the above-described vehicle capable of the external charging by using the charging cable, there are cases where proper connection of the charging cable to the inlet is set as one of conditions for starting the charging. When the external charging is performed in such vehicle, in a case where a user unfortunately does not notice that the connection of the charging cable is incomplete and the charging cable is not completely fitted, there is a possibility that charging is not executed against the intention of the user. As a result, when the user expects the completion of the charging and tries to drive the vehicle, a situation can occur in which the user cannot drive the vehicle due to non-execution of the charging of the vehicle.

[0006] In such a case, when the user has detached the charging cable without realizing the incomplete connection of the charging cable, there is a possibility that the user cannot subsequently realize why the charging has not been executed so that the user develops an uncomfortable feeling or distrusts the system.

SUMMARY OF THE INVENTION

[0007] ' According to the invention, in a vehicle capable of external charging by using a detachable charging cable, it becomes possible to subsequently realize a cause of non-execution of charging when the charging has not been executed due to incomplete connection of the charging cable to an inlet of the vehicle.

[0008] A first aspect of the invention relates to a vehicle. The vehicle is capable of charging by using electric power from an external power supply via a detachable charging cable. The vehicle includes a rechargeable power storage device, a connection section for connecting a connector of the charging cable, a charging device for charging the power storage device by using the electric power from the external power supply supplied to the connection section by the charging cable, and a control device for controlling a charging operation of the charging device. The connector includes a connection detection device for detecting connection between the connector and the connection section. The control device determines whether or not the connection between the connector and the connection section is in an incompletely connected state based on a state of a signal from the connection detection device and, when the connection between the connector and the connection section is in the incompletely connected state, the control device prohibits execution of the charging operation, and stores non-execution of the charging operation due to the incompletely connected state.

[0009] The connection detection device may have a first detection section and a second detection section. In response to the state of the signal from the connection detection device and based on the first detection section, the control device may determine whether or not the connection between the connector and the connection section is in the incompletely connected state according to the state of the signal based on the second detection section.

[0010] The state of the signal may have a first state generated when only the first detection section is connected to a terminal section of the connection section, and a second state that is different from the first state and generated when both of the first and second detection sections are connected to the terminal section. The control device may determine that the connection between the connector and the connection section is in the incompletely connected state when the state of the signal is the first state.

[0011] When the first state has continued for a predetermined time period, the control device may determine that the connection between the connector and the connection section is in the incompletely connected state.

[0012] When the state of the signal is the second state, the control device may determine that the connection between the connector and the connection section is in a completely connected state, and also permit the execution of the charging .operation.

[0013] When the state of the signal is a third state that is different from the first or second state, the control device may^etermine that the connector is not connected to the connection section. [0014] A second aspect of the invention relates to a control method for a vehicle. Herein, the vehicle is capable of charging by using electric power from an external power supply via a detachable charging cable. The vehicle includes a rechargeable power storage device, a connection section for connecting a connector of the charging cable, and a charging device for charging the power storage device by using the electric power from the external power supply supplied to the connection section by the charging cable. The connector includes a connection detection device for detecting connection between the connector and the connection section. The control method includes receiving a state of a signal from the connection detection device, determining whether or not the connection between the connector and the connection section is in an incompletely connected state based on the state of the signal, prohibiting execution of a charging operation of the charging device when it is determined that the connection between the connector and the connection section is in the incompletely connected state, and storing non-execution of the charging operation due to the incompletely connected state when it is determined that the connection between 'the connector and the connection section is in the incompletely connected state.

[0015] According to the invention, in the vehicle capable of external charging by using the detachable charging cable, it becomes possible to subsequently realize the cause of the non-execution of the charging when the charging has not been executed due to the incomplete connection of the charging cable to an inlet of the vehicle.

BRIEF DESCRIPTION, OF THE DRAWINGS

[0016] Features, advantages, and technical and industrial significance of exemplary embodiments of the invention will be described below with reference to the accompanying drawings, in which like numerals denote like elements, and wherein:

FIG. 1 is a schematic diagram of a charging system including a vehicle according to the present embodiment;

FIG. 2 is a view for explaining a charging circuit shown in FIG. 1 in greater detail;

FIG. 3 is a view of an outer appearance of a charging cable of FIG. 1 ; FIG. 4 is a time chart for explaining a charging operation when a connector is in a fitted state;

FIG. 5 is a time chart for explaining the charging operation when the connector is in a half-fitted state;

FIG. 6 is a flowchart for explaining a charging suspension determination process executed in a vehicle electronic control unit (ECU) in the present embodiment; and

FIG. 7 is a flowchart for explaining a log recording process in charging suspension executed in the vehicle ECU in the present embodiment. ,

DETAILED DESCRIPTION OF EMBODIMENTS

[0017] A detailed description will be given hereinbelow of an embodiment of the invention with reference to the drawings. In the drawings, the same or equivalent portions are denoted by the same reference numerals and the description thereof will not be repeated.

[0018] FIG. 1 is a schematic diagram of a charging system of a vehicle 10 according to the embodiment. Note that, as long as the vehicle 10 can be driven by electric power from a power storage device that can be charged using an external power supply, the configuration of the vehicle 10 is not particularly limited. Examples of the vehicle 10 include a hybrid vehicle, an electric vehicle, and a fuel cell vehicle. In addition, as long as a vehicle has a rechargeable power storage device mounted thereon, the invention is applicable to the vehicle even when the vehicle is driven by, e.g., an internal combustion engine.

[0019] With reference to FIG. 1 , the vehicle 10 includes an inlet 270, a charging device 160, a relay 155, a power storage device 150, a drive section 20, a vehicle electronic control unit (ECU) 170, and a voltage sensor 182. The drive section 20 includes a motor drive device 180, a motor generator (hereinafter also referred to as an "MG") 120, and a drive wheel 130.

[0020] To the inlet 270, a connector 310 of a charging cable 300 is connected. In addition, the charging device 160 is connected to the inlet 270 via power lines ACL 1 and ACL 2. Further, the charging device 160 is connected to the power storage device 150 via the relay 155. On the basis of a control signal PWE from the vehicle ECU 170, the charging device 160 converts AC power supplied from an external power supply 402 of the vehicle into DC power with which the power storage device 150 can be charged, and supplies the DC power to the power storage device 150.

[0021] The power storage device 150 is a power storage element configured to be rechargeable. The power storage device 150 includes, e.g., a secondary battery such as a lithium-ion battery, a nickel-hydrogen battery, or a lead battery, or a power storage element such as an electric double layer capacitor or the like.

[0022] The power storage device 150 stores charging power supplied from the charging device 160. The power storage device 150 is connected to the motor drive - device 180 that drives the MG 120, and supplies the DC power used for generating a driving force for driving the vehicle to the motor drive device 180. In addition, the power storage device 150 stores electric power generated in the MG 120.

[0023] In addition, although not shown, the power storage device 150 further includes a voltage sensor for detecting the voltage of the power storage device 150 and a current sensor for detecting the current inputted and outputted to and from the power storage device 150, and the detected values of the voltage and the current detected by these sensors are outputted to the vehicle ECU 170.

[0024] The motor drive device 180 is connected to the power storage device 150 and the MG 120. The motor drive device 180 is controlled by the vehicle ECU 170 to convert electric power supplied from the power storage device 150 into electric power for driving the MG 120. The motor drive device 180 includes, e.g., a three-phase inverter.

[0025] The MG 120 is connected to the motor drive device 180 and the drive wheel 130 via a power dividing mechanism and a final reduction gear that are not shown. The MG 120 receives electric power supplied from the motor drive device 180 to generate the driving force for driving the vehicle 10. In addition, the MG 120 receives a rotational force from the drive wheel 130 to generate the AC power, and also generate a regenerative braking force by a regenerative torque instruction from the vehicle ECU 170. The MG 120 includes, e.g., a three-phase AC generator having a rotor in which a permanent magnet is buried and a stator having a y-connected three-phase coil.

[0026] In a hybrid vehicle having an engine (not shown) amounted thereon in addition to the MG 120, control is executed by the vehicle ECU 170 such that driving forces of the engine and the MG 120 have an optimum ratio.

[0027] The voltage sensor 182 is provided between the power lines ACL 1 and ACL 2, and detects the voltage of electric power supplied from the external power supply 402. In addition, the voltage sensor 182 outputs a detected value VAC of the voltage to the vehicle ECU 170.

[0028] The relay 155 is provided in a path connecting the charging device 160 and the power storage device 150. The relay 155 is controlled by a control signal SE from the vehicle ECU 170, and switches between the supply and interruption of electric power from the charging device 160 to the power storage device 150. Note that, although the relay 155 is provided independently in the present embodiment, the relay 155 may also be included in the power storage device 150 or the charging device 160.

[0029] Although not shown in FIG. 1 , the vehicle ECU 170 includes a central processing unit (CPU), a storage device, and input/output buffers, receives a signal from each sensor, outputs a control instruction to each device, and also performs control of the vehicle 10 and each device. The control can be performed not only by software but also by constructing dedicated hardware (an electronic circuit).

[0030] The vehicle ECU 170 receives a signal SIG indicative of the connection of the cable and a pilot signal CPLT from the charging cable 300 via the inlet 270. In addition, the vehicle ECU 170 receives the voltage detected value VAC of the received electric power from the voltage sensor 182.

[0031] Further, the vehicle ECU 170 receives the input of detected values of a current, a voltage, and a temperature from sensors (not shown) provided in the power storage device 150, and calculates a state amount (hereinafter referred to as a "state of charge (SOC)") indicative of a charge state of the power storage device 150.

[0032] On the basis of these information items, the vehicle ECU 170 controls the charging device 160 and the relay 155 in order to charge the power storage device 150.

[0033] The charging cable 300 includes the connector 310 provided at the end portion on the vehicle side, a plug 320 provided at the end portion on the external power supply side, a charging circuit interrupt device (hereinafter also referred to as a "CCID") 330, and an electric wire section 340 that connects the individual devices to input and output electric power and control signals.

[0034] The electric wire section 340 includes an electric wire section 340 A that connects the plug 320 and the CCID 330, and an electric wire section 340B that connects the connector 310 and the CCID 330. In addition, the electric wire section 340 includes power lines 341 for transmitting electric power from the external power supply 402.

[0035] The charging cable 300 is connected using an outlet 400 of the external power supply 402 (e.g., a commercial power supply) and the plug 320 of the charging cable 300. The connector 310 of the charging cable 300 and the inlet 270 provided in a body of the vehicle 10 are connected, and electric power from the external power supply 402 of the vehicle is transmitted to the vehicle 10. The charging cable 300 is attachable and detachable to and from the external power supply 402 and the vehicle 10.

(0036] Inside the connector 310, a connection detection device 312 for detecting the connection of the connector 310 is provided, and detects the connection state between the inlet 270 and the connector 310. The connection detection device 312 outputs the signal SIG indicative of the connection state to the vehicle ECU 170 of the vehicle 10 via the inlet 270. The details of the connection detection device 312 will be described later in FIG. 2.

[0037] The CCID 330 includes a CCID relay 332 and a control pilot circuit 334. The CCID relay 332 is inserted between the power lines 341 in the charging cable 300. The CCID relay 332 is controlled by the control pilot circuit 334. When the CCID relay 332 is opened, the electric circuit is interrupted in the charging cable 300. On the other hand, when the CCID relay 332 is closed, electric power is supplied from the external power supply 402 to the vehicle 10. [0038] The control pilot circuit 334 outputs the pilot signal CPLT to the vehicle ECU 170 via the connector 310 and the inlet 270. The pilot signal CPLT is a signal for reporting a rated current of the charging cable 300 from the control pilot circuit 334 to the vehicle ECU 170. In addition, the pilot signal CPLT is also used as a signal for remotely controlling the CCID relay 332 from the vehicle ECU 170 on the basis of the potential of the pilot signal CPLT manipulated by the vehicle ECU 170. The control pilot circuit 334 controls the CCID relay 332 on the basis of a change in the potential of the pilot signal CPLT.

[0039] FIG. 2 is a view for explaining the charging circuit shown in FIG. 1 in greater detail. Note that the description of elements in FIG. 2 that are denoted by the same reference numerals as those in FIG. 1 will not be repeated.

[0040] With reference to FIG. 2, the CCID 330 further includes an electromagnetic coil 606, a leak detector 608, a CCID control section 610, a voltage sensor 650, and a current sensor 660 in addition to the CCID relay 332 and the control pilot circuit 334. In addition, the control pilot circuit 334 includes an oscillator 602, a resistor R20, and a voltage sensor 604.

[0041] Although not shown, the CCID control section 610 includes a CPU, a storage device, and input/output buffers, performs the input and output of signals of each sensor and the control pilot circuit 334, and also controls the charging Operation of the charging cable 300. .

[0042] The oscillator 602 outputs a non-oscillating signal when the potential of the pilot signal CPLT detected by the voltage sensor 604 is a prescribed potential and, when the potential of the pilot signal CPLT is lowered from the prescribed potential, the oscillator 602 is controlled by the CCID control section 610 to output a signal which oscillates at a prescribed frequency (e.g., 1 kHz) and duty cycle.

[0043] Note that the potential of the pilot signal CPLT is manipulated by the vehicle ECU 170, as described later in FIG. 4. In addition, the duty cycle is set on the basis of the rated current that can be supplied from the external power supply 402 to the vehicle 10 via the charging cable 300. [0044] As described above, the pilot signal CPLT oscillates at a prescribed cycle when the potential of the pilot signal CPLT is lowered from the prescribed potential. At this point, a pulse width of the pilot signal CPLT is set on the basis of the rated current that can be supplied from the external power supply 402 to the vehicle 10 via the charging cable 300. That is, on the basis of the duty represented by the ratio of the pulse width to the oscillation cycle, the rated current is reported to the vehicle ECU 170 of the vehicle 10 from the control pilot circuit 334 by using the pilot signal CPLT.

[0045] Note that the rated current is determined for each charging cable so that, when the type of the charging cable 300 differs, the value of the rated current differs. Consequently, it follows that the duty of the pilot signal CPLT differs for each charging cable 300.

[0046] On the basis of the duty of the pilot signal CPLT received via a control pilot line LI, the vehicle ECU 170 is capable of detecting the rated current that can be supplied from the external power supply 402 to the vehicle 10 via the charging cable 300.

[0047] When the potential of the pilot signal CPLT is further lowered by the vehicle ECU 170, the control pilot circuit 334 supplies a current to the electromagnetic coil 606. When the current is supplied from the control pilot circuit 334, the electromagnetic coil 606 generates an electromagnetic force, and closes a contact of the CCID relay 332 to establish an energized state.

[0048] The leak detector 608 is provided at some midpoint in the power lines 341 of the charging cable 300 inside the CCID 330, and detects the presence or absence of the leak. Specifically, the leak detector 608 detects the balanced state of currents flowing in mutually opposite directions in a pair of the power lines 341 , and detects the occurrence of the leak when the balanced state is lost. Although not shown, when the leak is detected by the leak detector 608, the power supply to the electromagnetic coil 606 is interrupted, the contact of the CCID relay 332 is opened, and a de-energized state is thereby established.

[0049] When the plug 320 of the charging cable 300 is inserted into the outlet 400, the voltage sensor 650 detects a power supply voltage transmitted from the external power supply 402, and reports the detected value to the CCID control section 610. In addition, the current sensor 660 detects a charging current flowing in the power lines 341 and reports the detected value to the CCID control section 610.

[0050] The connection detection device 312 included in the connector 310 includes resistors Rl 1 and R12, and a switch SW10.

[0051] The resistor Rl 1 is connected between a connection signal line L3 and a ground line L2. In addition, the switch SW10 and the resistor R12 connected in series are connected in parallel with the resistor Rl l between the connection signal line L3 and the ground line L2. The switch SW10 is interlocked with an operation button and an engagement hook of the connector 310 described later in FIG. 3. The contact of the switch SW10 is closed in a state where the connector 310 is completely connected to the inlet 270 (hereafter also referred to as a fitted state), and the contact thereof is opened in an incompletely connected state where the connector 310 is half-connected to the inlet 270 (hereinafter also referred to as a half-fitted state).

[0052] By having the configuration described above, when the connector 310 is separated from the inlet 270, a signal having a potential (e.g., VI 1) determined by the voltage of a power supply node 511 and a pull-up resistor R10 that are included in the vehicle ECU 170 is generated as the signal SIG in the connection signal line L3. In addition, when the connector 310 and the inlet 270 are in the fitted state, a signal having a potential (e.g., VI 3) determined by the voltage of the power supply node 511, the pull-up resistor R10, and the resistors Rl l and R12 is generated as the signal SIG in the connection signal line L3. Further, when the connector 310 and the inlet 270 are in the half-fitted state, the switch SW10 is in an opened state so that a signal having a potential (e.g., V12) determined by the voltage of the power supply node 511 , the pull-up resistor R 10, and the resistor Rl l is generated as the signal SIG in the connection signal line L3.

[0053] At this point, the magnitude of the potential of the signal SIG generated in each state satisfies VI 1 > V12 > V13. Consequently, by detecting the magnitude of the potential of the signal SIG, the vehicle ECU 170 is capable of detecting the connection state of the connector 310. [0054] Note that, in the above description, the resistor Rl l corresponds to a "first detection section" in the invention, and the resistor R12 corresponds to a "second detection section" in the invention. In addition, a case where the potential V of the signal SIG satisfies V12≥V > V13 corresponds to a "first state" in the invention, a case where the potential V of the signal SIG satisfies VI 3 > V corresponds to a "second state" in the invention, and a case where the potential V thereof satisfies V > V12 corresponds to a "third state" in the invention,

[0055] In the vehicle 10, the vehicle ECU 170 further includes a resistance circuit 502, input buffers 504 and 506, and a CPU 508 in addition to the above-mentioned power supply node 511 and pull-up resistor R10. The resistance circuit 502 includes pull-down resistors Rl and R2, and a switch SWl . The pull-down resistor Rl and the switch SWl are connected in series between the control pilot line LI in which the pilot signal CPLT is communicated and a vehicle ground 512. The pull-down resistor R2 is also connected in series between the control pilot line LI and the vehicle ground 512. The switch SWl is brought into energization or de-energization in accordance with the control signal SI from the CPU 508.

[0056] The resistance circuit 502 is a circuit for manipulating the potential of the pilot signal CPLT from the vehicle 10 side.

[0057] The input buffer 504 receives the pilot signal CPLT of the control pilot line LI, and outputs the received pilot signal CPLT to the CPU 508. The input buffer 506 receives the signal SIG from the connection signal line L3 connected to the connection detection device 312 of the connector 310, and outputs the received signal SIG to the CPU 508.

[0058] The CPU 508 receives the pilot signal CPLT and the signal SIG from the input buffers 504 and 506. By detecting the oscillation state and the duty cycle of the pilot signal CPLT, the CPU 508 detects the rated current of the charging cable 300, as described above.

[0059] The CPU 508 detects the potential of the signal SIG to thereby detect the connection state of the connector 310. When the potential of the signal SIG becomes VI 2 or less, the CPU 508 sets a connection signal CNCT indicating that terminals of the ground line L2 and the connection signal line L3 in the inlet 270 are connected to the corresponding terminals in the connector 310 to ON. In addition, when the potential of the signal SIG becomes V13 or less, the CPU 508 sets a fitting signal PISW indicating that the connector 310 and the inlet 270 are brought into the fitted state to ON.

[0060] On the basis of the potential of the signal SIG and the oscillation state of the pilot signal CPLT, the CPU 508 manipulates the potential of the pilot signal CPLT by controlling the control signal SI of the switch SW1. With this operation, the CPU 508 is capable of remotely controlling the CCID relay 332. Subsequently, electric power is transmitted from the external power supply 402 to the vehicle 10 via the charging cable 300.

[0061] With reference to FIGS. 1 and 2, when the contact of the CCID relay 332 is closed, AC power is supplied to the charging device 160 from the external power supply 402, and charging preparation from the external power supply 402 to the power storage device 150 is completed. The CPU 508 causes the charging device 160 to perform electric power conversion by outputting the control signal PWE to the charging device 160, and also executes the charging of the power storage device 150 by outputting the control signal SE to close the contact of the relay 155.

[0062] FIG. 3 is a view of an outer appearance of the charging cable 300 of FIG. T . With reference to FIG. 3, as described above, the charging cable 300 includes the connector 310, the plug 320, and the electric wire section 340. In addition, the connector 310 further includes an operation button 314, a coupler section 315, and an engagement hook 316.

[0063] A plurality of connection terminals (not shown) are provided in the coupler section 315, and the coupler section 315 is connected to the inlet 270 of the vehicle 10, whereby the power lines, the ground line, and the signal line in the electric wire section 340 are connected to the power lines, the ground line, and the signal line on the vehicle 10 side.

[0064] In the present embodiment, the operation button 314 is a button for operating the engagement hook 316 for preventing the removal of the connector 310, and the engagement hook 316 operates in interlock with the operation of the operation button 314.

[0065] Specifically, when the connector 310 is completely connected to the inlet 270 and the fitted state is thereby established, the engagement hook 316 is hooked onto an engagement hook reception section (not shown) on the vehicle 10 side, and the accidental removal of the connector 310 from the inlet 270 is prevented. When the operation button 314 is pushed down, the engagement hook 316 is detached from the engagement hook reception section, whereby it becomes possible to remove the connector 310 from the inlet 270.

[0066] As described in FIG. 2, the switch SW10 incorporated in the connector 310 is brought into the energized or de-energized state in interlock with the operation of each of the operation button 314 and the engagement hook 316. When the connector 310 and the inlet 270 are in the fitted state, the engagement hook ^' 316 is hooked onto the engagement hook reception section and, at this point, the switch SW10 is in the energized , state.

[0067] On the other hand, when the connector 310 and the inlet 270 are in the half _: fitted state, the engagement hook 316 is pushed up by the engagement hook reception section, i.e., the operation button 314 is pushed down and, in this state, the switch SW10 is in the de-energized state.

[0068] In the charging system of the vehicle having the configuration described above, there are cases where reliable connection of the connector of the charging cable to the inlet of the vehicle is set as one of conditions for the execution of the charging. The reason for this is to prevent the induction of the damage or failure of the device due to the occurrence of an arc between terminals resulting from the separation of the terminal section of the connector during energization when the connection of the connector is loose or the connecter is detached during the charging by a user.

[0069] Therefore, for example, in the configuration such as that of the charging cable 300 shown in FIG. 3, there are cases where, in addition to the state where the terminal section of the connector 310 is connected to the terminal section of the inlet (i.e., the connection signal CNCT is ON), the state where the engagement hook 316 of the connector 310 is reliably hooked onto the engagement hook reception section (i.e., the fitting signal PISW is ON) is set as the condition for the execution of the charging. By setting the states as the conditions, it is possible to prevent the connector from being accidentally detached from the inlet during the charging. Further, even when the user tries to detach the connector during the charging, the electric power supply is stopped at the point when the operation button is operated by the user in order to cause the engagement hook to operate, and hence the connector is already in the de-energized state when the terminal section of the connector is separated from the terminal section of the inlet, and the occurrence of the arc or the like can be thereby prevented.

[0070] On the other hand, under the charging execution conditions described above, when the connection of the connector is incomplete, the charging is not executed. Accordingly, when the connector and the inlet are not in the completely fitted state due to the incomplete connection of the connector by the user or the occurrence of a connection failure in the terminal section, the charging is not executed. If the user does not notice the non-execution of the charging, a situation can occur that the charging is not performed at all at the point when the user expects the completion of the charging and tries to drive the vehicle.

[0071] In such case, there are cases where the user notices the non-execution of the charging after the charging cable is detached. In this case, there is a possibility that the user cannot realize the cause of the non-execution of the charging, and considers that some failure has occurred in the charging system. In addition, with this, a situation can occur that a dealer is asked to repair the charging system by the user, or the dealer cannot identify the cause and cannot explain the cause to the user properly when the dealer receives a complaint about the non-execution of the charging.

[0072] To cope with this, in the present embodiment, in the charging system of the vehicle capable of the external charging by using the charging cable, there is employed a method in which, separately from the occurrence of other failures of the device or the like, the fact that the charging has not been executed due to the incomplete connection of the connector of the charging cable is stored as a log. By employing such method, it becomes possible to subsequently realize that the charging has not been executed due to the incomplete connection of the connector.

[0073] FIG. 4 is a time chart for explaining the charging operation in the case of the fitted state where the connector 310 is completely connected to the inlet 270. In FIG.

4 and FIG. 5 described later, the horizontal axis indicates time, while the vertical axis indicates the potential of the pilot signal CPLT, the potential of the signal SIG, the state of each of the connection signal CNCT and the fitting signal PISW, the state of the switch

5 W l , the state of the CCID relay 332, the execution state of the charging process, and the state of a half-fitting detection flag FLG.

[0074] With reference to FIGS. 2 and 4, until a time tlO, the charging cable 300 is not connected to the vehicle 10 or the external power supply 402. In this state, each switch and the CCID relay 332 are in an OFF state, and the potential of the pilot signal CPLT is 0 V. The potential of the signal SIG is V 11 (> 0 V).

[0075] At the time tlO, when the plug 320 of the charging cable 300 is connected to the outlet 400 of the external power supply 402, the control pilot circuit 334 receives electric power from the external power supply 402 to generate the pilot signal CPLT.

[0076] Note that the connector 310 of the charging cable 300 is not connected to the inlet 270 yet at the time tlO. In addition, the potential of the pilot signal CPLT is VI (e.g., 12 V) and the pilot signal CPLT is in a non-oscillating state.

[0077] At a time ti l, when the connector 310 is connected to the inlet 270, the potential of the signal SIG is lowered by the connection detection device 312. In FIG. 4, the connector 310 and the inlet 270 are in the fitted state, and hence the switch SW10 in the connection detection device 312 is closed, and the potential of the signal SIG is lowered to V13 by the resistors Rl l and R12. With this operation, each of the connection signal CNCT and the fitting signal PISW is set to ON, and the connection between the connector 310 and the inlet 270 is detected by the CPU 508. [0078] At this point, the control pilot line LI is connected so that the potential of the pilot signal CPLT is lowered to V2 (e.g., 9 V) by the pull-down resistor R2 of the resistance circuit 502.

[0079] At a time tl2, the CCID control section 610 detects that the potential of the pilot signal CPLT is lowered to V2. In response to this, the CCID control section 610 causes the pilot signal CPLT to oscillate.

[0080] When detecting the oscillation of the pilot signal CPLT, the CPU 508 detects the rated current of the charging cable 300 based on the duty of the pilot signal CPLT, as described above.

[0081] Subsequently, in order to start the charging operation, the CPU 508 activates the control signal SI to turn the switch SW1 ON. In response to this, the potential of the pilot signal CPLT is lowered to V3 (e.g., 6 V) by the pull-down resistor R2 (a time tl 3 in FIG. 4).

[0082] When the CCID control section 610 detects that the potential of the pilot signal CPLT is lowered to V3, the contact of the CCID relay 332 is closed at a time tl4, and electric power from the external power supply 402 is transmitted to the vehicle 10 via the charging cable 300.

[0083] Thereafter, when the CPU 508 detects the AC voltage VAC, the contact of the relay 155 (FIG. 1) is closed and also the charging device 160 (FIG. 1) is controlled, and the charging of the power storage device 150 (FIG. 1) is started (a time tl 5 in FIG. 4).

[0084] When it is determined that the charging of the power storage device 150 progresses and the power storage device 150 is fully charged, the CPU 508 stops the charging process (a time tl 6 in FIG. 4) and also deactivates the control signal S I to bring the switch SW1 into the de-energized state (at a time tl7 in FIG. 4). With this operation, the potential of the pilot signal CPLT becomes V2, the CCID relay 332 is brought into the de-energized state (a time tl 8 in FIG. 4), and the charging operation is ended.

[0085] Note that, in the case of FIG. 4, since the connector 310 and the inlet 270 are in the fitted state, the half-fitting detection flag FLG remains OFF.

[0086] Next, by using FIG. 5, a description will be given of the charging operation when the connector 310 and the inlet 270 are in the half-fitted state.

[0087] With reference to FIGS. 2 and 5, the plug 320 of the charging cable 300 is connected to the outlet 400 of the external power supply 402 at a time t20, and the connector 310 is connected to the inlet 270 at a time t21.

[0088] However, in FIG. 5, the connection between the connector 310 and the inlet 270 is incomplete, and hence the switch SW10 is not closed, and the potential of the signal SIG becomes VI 2. As a result, the connection signal CNCT is set to ON, but the fitting signal PISW remains OFF.

[0089] With this operation, the CPU 508 detects that the connector 310 and the inlet 270 are in the half-fitted state.

[0090] In response to the detection of the lowering of the potential of the pilot signal CPLT to V2 at the time t21, the CCID control section 610 brings the pilot signal CPLT into the oscillating state (a time t22 in FIG. 5). However, since the CPU 508 has detected the half-fitted state of the connector 310, the CPU 508 maintains the switch SW1 in a deactivated state. With this operation, the potential of the pilot signal CPLT is not lowered to V3, and hence the CCID relay 332 is not closed, and the charging operation is not started.

[0091] On the other hand, the CPU 508 measures a time of continuation of a state where the pilot signal CPLT is in the- oscillating state, the connection signal CNCT is ON, and the fitting signal PISW is OFF (i.e., the half-fitted state). Subsequently, in response to that the state has continued for a predetermined time period TIM, the CPU 508 determines that the charging operation cannot be executed due to the half-fitted state, and' sets the half-fitting detection flag FLG to ON to suspend the charging.

[0092] The reason why the continuation time of the half-fitted state is considered herein is to prevent the charging from being accidentally suspended by a temporary half-fitted state generated until the user releases the operation button 314 when the user connects the connector 310 to the inlet 270 while pressing down the operation button 314 (FIG. 3).

[0093] In response to that the half-fitting detection flag FLG is set to ON, the CPU 508 further stores the non-execution of the charging due to the half-fitted state between the connector 310 and the inlet 270 as the log. Subsequently, on the basis of the stored information, the CPU 508 outputs the cause of the suspension of the charging to an alarm device (not shown), or outputs the stored information in response to the request from other analysis devices or the like.

[0094] FIG. 6 is a flowchart for explaining a charging suspension determination process executed in the vehicle ECU 170. In each of the flowcharts shown in FIG. 6 and FIG. 7 described later, the process is implemented by calling a program pre-stored in the vehicle ECU 170 from a main routine and executing the program at a predetermined period. Alternatively, with regard to a part of steps, the process may be implemented by constructing dedicated hardware (an electronic circuit).

[0095] With reference to FIGS. 2 and 6, the vehicle ECU 170 determines whether or not a charging abnormality occurs in a step (hereinafter the step is abbreviated as S) 100. Examples of the charging abnormality include the abnormality in the charging device 160 (FIG. 1) and the operation of the leak detector 608 of the CCID 330.

[0096] When the abnormality occurs (YES in SI 00), the. process advances to SI 30 where the vehicle ECU 170 sets a charging suspension request flag to ON, and returns the process to the main routine. When the charging suspension request flag is set to ON, the charging operation is suspended or the start of the charging operation is prohibited.

[0097] When the charging abnormality does not occur (NO in SI 00), the process advances to SI 10 where the vehicle ECU 170 then determines whether or not the power storage device 150 (FIG. 1) is fully charged.

[0098] When the power storage device 150 is fully charged (YES in SI 10), the process advances to S I 30. ^

[0099] When the power storage device 150 is not fully charged (NO in S I 10), the process advances to SI 20 where the vehicle ECU 170 determines whether or not the connector 310 and the inlet 270 are in the half-fitted state. Specifically, as described in FIG. 5, it is determined whether or not the state where the pilot signal CPLT is in the oscillating state, the connection signal CNCT is ON, and the fitting signal PISW is OFF has continued for the predetermined time period TIM.

[0100] When the connector 310 and the inlet 270 are not in the half-fitted state (NO in S I 20), since there is no cause of the suspension of the charging operation, the vehicle ECU 170 returns the process to the main routine, and executes or continues the charging operation in response to that the other conditions are satisfied.

[0101] On the other hand, when the connector 310 and the inlet 270 are in the half-fitted state (YES in SI 20), the process advances to SI 30 where the vehicle ECU 170 sets the charging suspension request flag to ON.

[0102] Although not shown, when the cause of the suspension of the charging is eliminated (e.g., recovery from the abnormal state or a reduction in charge amount), the charging suspension request flag is set to OFF.

[0103] FIG. 7 is a flowchart for explaining a log recording process in the charging suspension executed in the vehicle ECU 170 in the present embodiment.

[0104] With reference to FIGS. 2 and 7, the vehicle ECU 170 determines whether or not it is immediately after the end of the charging in S200. Specifically, it is determined whether or not the charging suspension request flag in the last charging operation is OFF, i.e., the charging suspension request flag is reset, and the charging suspension request flag in the current charging operation is set to ON.

[0105] When it is not immediately after the end of the charging (NO in S200), the vehicle ECU 170 returns the process to the main routine.

[0106] When it is immediately after the end of the charging (YES in S200), the process advances to S210 where the vehicle ECU 170 determines whether or not the cause of the suspension of the charging corresponds to none of the full charge and the charging abnormality.

[0107] When the cause thereof corresponds to one of the full charge and the charging abnormality (NO in S210), the process is returned to the main routine.

[0108] When the cause thereof corresponds to none of the full charge and the charging abnormality (YES in S210), the process advances to S220 where the vehicle ECU 170 determines whether or not the charging has been suspended by the detection of the half-fitted state of the connector 310. Specifically, it is determined whether or not the state where the pilot signal CPLT is in the oscillating state, the connection signal CNCT is ON, and the fitting signal PISW is OFF has continued for the predetermined time period TIM.

[0109] When the charging has not been suspended by the detection of the half-fitted state (NO in S220), the process is returned to the main routine.

[0110] When the charging has been suspended by the detection of the half-fitted state (YES in S220), the process advances to S230 where the vehicle ECU 170 stores the suspension of the charging by the detection of the half-fitted state as the log.

[0111] : Although not shown in FIG. 7, in a case other than the case where the charging is suspended by the detection of the half-fitted state, the corresponding cause of the suspension of the charging may also be stored as the log. Further, irrespective of the cause of the suspension of the charging, the suspension of the charging may also be stored as the log.

[0112] By performing the control according to the above-described process, in the vehicle capable of the external charging by using the charging cable, it is possible to store the cause of the non-execution when the charging has not been executed due to the incomplete connection of the charging cable to the inlet of the vehicle separately from other causes for the suspension of the charging. With this arrangement, it is possible to subsequently realize that the charging has not been executed due to the incomplete connection of the charging cable, and hence it is possible to suppress the occurrence of an unnecessary complaint by the user, and ask the user to follow appropriate usage.

[0113] The disclosed embodiment is to be considered in all aspects as illustrative and not restrictive. The scope of the invention is indicated by the appended claims, rather than by the foregoing description, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.