vehicle

Abstract

To provide technique capable of restraining consumption of a relay part by switching of the relay part before start of external charging when an external power source is electrically connected to a power incoming part during execution of solar charging in a vehicle capable of executing the solar charging and the external charging.SOLUTION: A vehicle 1 comprises a power storage device 5, an inlet 40, a SMR 50, a capacitor 55, a solar panel 90 and an ECU 70. The ECU 70 is configured so as to execute solar charging and external charging. The ECU 70 ends the solar charging when an external power source 110 is electrically connected to the inlet 40 during execution of the solar charging and executes pre-charging control which charges the discharged capacitor 55 due to end of the solar charging by utilizing electrically generated power and executes the external charging by turning the SMR 50 on after execution of the pre-charging control.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a vehicle, and more particularly to a vehicle equipped with a power storage device. [Background technology]

[0002] JP 2018-082576 A (Patent Document 1) discloses a vehicle equipped with a power storage device, a power receiving device, and a solar cell. This vehicle is configured to be capable of performing external charging, which charges the power storage device using power supplied from an external power source provided outside the vehicle through the power receiving device. Furthermore, the vehicle is configured to be capable of performing solar charging, which charges the power storage device using power generated by the solar cell. If external charging is started while solar charging is being performed, there is a possibility that the charging power of the power storage device cannot be appropriately managed. Therefore, in this vehicle, solar charging is prohibited from being performed until a standby time has elapsed after the ignition switch is turned off, and solar charging is permitted when the standby time has elapsed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-082576 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a vehicle, a relay unit (SMR: System Main Relay) is provided between a power storage device that stores power for driving and a pair of power lines to which a power receiving unit that receives power from an external power source is connected. A voltage smoothing capacitor is provided between the pair of power lines between the relay unit and the power receiving unit. In a situation where the capacitor is discharged, if the relay unit is turned on at the start of external charging, an inrush current may flow from the power storage device to the capacitor. In order to reduce such an inrush current, the relay unit may be switched so that the capacitor is pre-charged before the start of external charging.

[0005] In a vehicle capable of performing both solar charging and external charging, an external power source may be electrically connected to the power receiving unit while solar charging is being performed. In this case, it may also be preferable to switch the relay unit to precharge the capacitor after discharging the capacitor and before starting external charging. However, the relay unit wears out the more times it is switched.

[0006] The present disclosure has been made to solve the above problems, and its purpose is to provide a technology that can suppress wear on a relay unit due to switching of the relay unit before external charging begins in a vehicle capable of performing solar charging and external charging, when an external power source is electrically connected to a power receiving unit while solar charging is being performed. [Means for solving the problem]

[0007] The vehicle of the present disclosure includes a power storage device, a power receiving unit, a relay unit, a capacitor, a solar cell, and a control device. The power receiving unit is configured to receive power from an external power source provided outside the vehicle. The relay unit is provided on a pair of power lines between the power storage device and the power receiving unit. The capacitor is provided between the pair of power lines between the relay unit and the power receiving unit. The solar cell is connected to the pair of power lines between the relay unit and the power receiving unit, and receives light energy to generate power. The control device is configured to perform solar charging, which charges the power storage device using power generated by the solar cell, and external charging, which charges the power storage device using power supplied from the external power source through the power receiving unit. When the external power source is electrically connected to the power receiving unit during solar charging, the control device terminates solar charging, and performs pre-charge control, which charges the capacitor discharged with the termination of solar charging, using the generated power, and performs external charging by turning on the relay unit after performing the pre-charge control.

[0008] With the above configuration, the control device does not need to switch the relay unit to execute precharge control of the capacitor using power supplied from the power storage device. As a result, the number of times the relay unit is switched before the start of external charging is reduced. Therefore, wear on the relay unit can be suppressed.

[0009] The relay unit may include a first relay, a second relay, and a precharge circuit. The first relay is provided on one of the pair of power lines. The second relay is provided on the other of the pair of power lines. The precharge circuit is connected in parallel to the second relay. The precharge circuit includes a third relay and a limiting resistor connected in series to the third relay. The control device may control the first relay, the second relay, and the third relay to an open state and terminate solar charging, and after performing the precharge control, perform external charging by controlling the first relay and the second relay to a closed state while controlling the third relay to an open state.

[0010] With the above configuration, it is not necessary to switch the third relay from an open state to a closed state for pre-charge control after solar charging ends and before external charging starts, which makes it possible to suppress wear on the third relay.

[0011] If the generated power is equal to or greater than a threshold value when solar charging is terminated, the control device may execute pre-charge control using the generated power.

[0012] With the above configuration, if the generated power when solar charging is terminated is large enough to charge the capacitor, pre-charge control is executed using the generated power by the solar cell. As a result, the generated power is effectively utilized without being wasted, and the number of times the relay unit is switched before external charging begins is reduced. Therefore, wear on the relay unit can be suppressed.

[0013] If the generated power is less than the threshold value when solar charging is terminated, the control device may execute pre-charge control using power supplied from the power storage device by controlling the relay unit.

[0014] With the above configuration, even if the generated power when solar charging is terminated is not large enough to fully charge the capacitor, the pre-charge control is executed using the power supplied from the power storage device, thereby reducing the inrush current when external charging starts.

[0015] The vehicle may further include a communication device that communicates with the vehicle to acquire sunlight information indicating a state of sunlight irradiation at a current location of the vehicle. The control device determines whether to execute pre-charge control using the generated power according to the sunlight information.

[0016] With the above configuration, even if a voltage sensor and a current sensor for calculating the power generated by the solar cell are not provided, it is possible to determine whether or not the pre-charge control is to be executed using the generated power. As a result, when the pre-charge control is executed using the power generated by the solar cell, the number of times the relay unit is switched before the start of external charging is reduced. As a result, it is possible to suppress wear of the relay unit. Effect of the Invention

[0017] According to the vehicle disclosed herein, in a vehicle capable of performing solar charging and external charging, a technology can be provided that can suppress wear on the relay unit due to switching of the relay unit before external charging begins when an external power source is electrically connected to the power receiving unit while solar charging is being performed. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a diagram illustrating a schematic configuration of a vehicle according to an embodiment of the present disclosure. [Diagram 2] 10 is a timing chart for illustrating control executed by an ECU of the comparative example from the end of solar charging to the start of external charging. [Diagram 3] 5 is a timing chart for illustrating SMR switching control executed by the ECU during the period from the end of solar charging to the start of external charging in this embodiment. [Figure 4] 4 is a flowchart showing an example of a process associated with solar charging and external charging. [Diagram 5] FIG. 13 is a diagram illustrating a schematic configuration of a vehicle according to a fifth modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference characters and their description will not be repeated.

[0020] In addition, the following will typically describe a case where the vehicle according to the present disclosure is an electric vehicle (EV (Electric Vehicle)), but the vehicle is not limited to an EV and may be a hybrid vehicle (HV (Hybrid Vehicle)) or a plug-in HV.

[0021] Fig. 1 is a diagram illustrating a schematic configuration of a vehicle according to an embodiment of the present disclosure. With reference to Fig. 1, vehicle 1 includes a power storage device 5, voltage sensors 57, 60, a current sensor 62, a temperature sensor 58, a system main relay (SMR) 50, a capacitor 55, and a discharge resistor 56. Vehicle 1 further includes a power control unit (PCU) 20, a motor generator (MG) 25, and drive wheels 30. Vehicle 1 further includes a charging device 200, a relay 59, an inlet 40, a solar unit 95, a relay 99, a start switch 80, a communication device 250, and an ECU 70.

[0022] The power storage device 5 is a power storage element that stores electric power for driving. The power storage device 5 includes, for example, a secondary battery such as a lithium ion battery or a nickel metal hydride battery, or an electric storage element such as an electric double layer capacitor. A lithium ion secondary battery is a secondary battery that uses lithium as a charge carrier, and may include not only a typical lithium ion secondary battery with a liquid electrolyte, but also an all-solid-state battery that uses a solid electrolyte. The power storage device 5 is charged during external charging of the vehicle 1 and solar charging.

[0023] The voltage sensor 57 detects the voltage VB of the power storage device 5. The current sensor 62 detects the current IB input to or output from the power storage device 5. The temperature sensor 58 detects the temperature of the power storage device 5.

[0024] The SMR 50 (relay unit) is provided on a pair of power lines (positive line PL and negative line NL) between the power storage device 5 and the inlet 40. The SMR 50 is provided for switching between electrical connection and disconnection between an electric load such as a PCU 20 (described later) and the power storage device 5. The positive line PL connects the positive electrode of the power storage device 5 to the PCU 20. The negative line NL connects the negative electrode of the power storage device 5 to the PCU 20. The SMR 50 includes relays SMRB, SMRG, SMRP, and a limiting resistor 52. The relay SMRB is provided on the positive line PL. The relay SMRG is provided on the negative line NL. The relay SMRP and the limiting resistor 52 are connected in series and connected in parallel to the relay SMRG.

[0025] In this embodiment, the "off state" of SMR 50 is a state in which relays SMRB, SMRG, and SMRP are open. The "on state" of SMR 50 is a state in which relays SMRB and SMRG are closed. To "turn on" SMR 50 is to switch SMR 50 from an off state to an on state. To "turn off" SMR 50 is to switch SMR 50 from an on state to an off state.

[0026] Each relay in the SMR 50 is a contact relay (mechanical relay). Therefore, while each relay is controlled to an open state, both ends of the relay can be completely electrically insulated. Each relay is controlled to an open state or a closed state according to a control command from the ECU 70 (described later).

[0027] Relay SMRP and limiting resistor 52 form a precharge circuit for reducing an inrush current flowing from power storage device 5 to capacitor 55. The inrush current occurs when SMR 50 is turned on with capacitor 55 discharged (for example, when external charging starts, when a start switch 80 described later is turned on). Therefore, before external charging starts, relay SMRB is controlled to a closed state, and then relay SMRP is controlled to a closed state before relay SMRG is controlled to a closed state. As a result, in a situation where the current is limited by limiting resistor 52, capacitor 55 is charged in advance (precharged) before external charging starts. As a result, the inrush current is reduced.

[0028] Capacitor 55 is provided between positive electrode line PL and negative electrode line NL. Capacitor 55 smoothes AC components of voltage fluctuations between positive electrode line PL and negative electrode line NL.

[0029] The discharge resistor 56 is connected in parallel to the capacitor 55. The discharge resistor 56 is provided to discharge the capacitor 55 after the SMR 50 is turned off. The voltage sensor 60 detects the voltage VH across the capacitor 55.

[0030] The PCU 20 performs bidirectional power conversion between the power storage device 5 and a MG 25 (described later). The PCU 20 includes, for example, an inverter and a converter.

[0031] The MG 25 is typically an AC rotating electric machine, for example, a three-phase AC synchronous motor with a permanent magnet embedded in the rotor. The MG 25 is driven by the PCU 20 to generate a rotational driving force. The driving force generated by the MG 25 is transmitted to the driving wheels 30. This causes the vehicle 1 to run.

[0032] The charging device 200 converts the power from the power supply facility 100 (described later) into DC power at the voltage level of the power storage device 5.

[0033] Relay 59 is provided between charging device 200 and power storage device 5. Relay 59 is controlled to an open state during solar charging, and is controlled to a closed state during external charging.

[0034] The inlet 40 is electrically connected to the charging device 200. The inlet 40 is provided as a power receiving unit configured to receive power from the power supply equipment 100. The charging device 200, the relay 59 and the inlet 40 are also referred to as an "external charging mechanism."

[0035] The power supply equipment 100 includes a connector 120 and an external power source 110. The connector 120 is configured to be connectable to the inlet 40. In the example of FIG. 1, the external power source 110 is an AC power source. Power supplied from the external power source 110 is supplied to the power storage device 5 through the charging device 200, a relay 59, and a positive electrode line PL and a negative electrode line NL. Note that the external power source 110 may be a DC power source, and in this case, the charging device 200 does not need to be provided in the vehicle 1. The power supply equipment 100 further includes a control circuit (not shown) that controls power supply from the external power source 110 to the connector 120.

[0036] The solar unit 95 includes a solar panel 90 , a DC / DC converter 97 , a voltage sensor 91 , a current sensor 92 , and a diode 98 .

[0037] The solar panel 90 is connected to the positive electrode line PL and the negative electrode line NL via a DC / DC converter 97 (described later) between the SMR 50 and the inlet 40. The solar panel 90 is a solar cell that receives light energy from the sun and generates power. Specifically, the solar panel 90 is configured to convert light energy into DC power and output the converted power to a power line 93.

[0038] The DC / DC converter 97 converts the power generated by the solar panel 90 into DC power at the voltage level of the power storage device 5 .

[0039] The voltage sensor 91 and the current sensor 92 are provided on the power line 93. The voltage sensor 91 and the current sensor 92 detect the voltage and current of the power line 93, respectively.

[0040] Diode 98 is provided between DC / DC converter 97 and positive line PL. Diode 98 is connected with the direction in which current flows from solar panel 90 to positive line PL as the forward direction. Providing diode 98 prevents the current flowing through positive line PL from flowing to solar panel 90. Diode 98 may also be provided between DC / DC converter 97 and negative line NL. Alternatively, a relay may be provided instead of diode 98 between DC / DC converter 97 and positive line PL and negative line NL.

[0041] The relay 99 is provided between the solar unit 95 and the pair of power lines (positive line PL and negative line NL). The relay 99 is controlled to a closed state while solar charging is being performed, and is controlled to an open state while the vehicle 1 is running. This makes it possible to protect the solar unit 95 in the event of a collision of the vehicle 1.

[0042] The start switch 80 receives an operation by a user to start up the driving system of the vehicle 1. Specifically, when the start switch 80 is turned on, a Ready-ON signal is output from the start switch 80 to the ECU 70 (described later). Upon receiving the Ready-ON signal, the ECU 70 switches the driving system of the vehicle 1 from a stopped state to an activated state, and turns on the SMR 50.

[0043] The communication device 250 is configured to access a network 300 such as the Internet by wireless communication. As an example, the communication device 250 acquires sunlight information indicating the sunlight irradiation state at the current position of the vehicle 1 from a weather forecast site on the network 300. Specifically, the sunlight information may be information indicating the amount of sunlight at the current position, or information indicating the weather (for example, whether the weather is sunny, cloudy, rainy, or snowy).

[0044] The ECU 70 includes a CPU (Central Processing Unit) and a memory (neither shown). The memory includes a ROM (Read Only Memory) and a RAM (Random Access Memory) (neither shown). The ROM stores programs executed by the CPU, etc. The RAM temporarily stores data referenced by the CPU, etc. Control of the ECU 70 is achieved by software processing, but may also be achieved by hardware created within the ECU 70.

[0045] The ECU 70 controls each device of the vehicle 1 according to each sensor signal and programs, data, and maps stored in the memory. As an example, the ECU 70 controls the SMR 50, the PCU 20, the relay 59, the charging device 200, the DC / DC converter 97, the relay 99, the communication device 250, and the like.

[0046] ECU 70 calculates the SOC (State of Charge) of power storage device 5 based on the detected values ​​of voltage sensor 57, current sensor 62, and temperature sensor 58. The SOC is calculated using a known method such as a method using an OCV-SOC curve (map or the like) that indicates the relationship between OCV (Open Circuit Voltage) and SOC.

[0047] The ECU 70 is configured to be able to perform solar charging for charging the power storage device 5 using power generated by the solar panel 90. Specifically, the ECU 70 controls the DC / DC converter 97 to convert the power generated by the solar panel 90 into DC power at a voltage level of the power storage device 5. The output power of the DC / DC converter 97 is supplied to the power storage device 5 via the positive electrode line PL, the negative electrode line NL, and the SMR 50.

[0048] The ECU 70 is configured to be capable of performing external charging for charging the power storage device 5 using power supplied from the external power source 110 through the inlet 40. The ECU 70 can perform external charging when the external power source 110 is electrically connected to the inlet 40. Specifically, the ECU 70 performs external charging by controlling the charging device 200 to convert the power supplied from the external power source 110 through the inlet 40 into DC power at a voltage level of the power storage device 5.

[0049] The ECU 70 can determine (detect) whether the external power source 110 is electrically connected to the inlet 40 based on a control pilot signal (not shown) transmitted between the ECU 70 and a control circuit of the power supply equipment 100. As an example, the ECU 70 executes this determination process depending on whether the signal is at a high level or a low level. The state of the vehicle 1 when the external power source 110 is electrically connected to the inlet 40 is also referred to as a "plugged-in state."

[0050] Hereinafter, a description will be given of switching control of the SMR 50 by the ECU 70 when the external power source 110 is electrically connected to the inlet 40 and external charging is started in a situation where solar charging is not being performed. In a situation where solar charging is not being performed, it is assumed that the relays SMRB, SMRG, and SMRP are in the open state.

[0051] First, the ECU 70 controls the relay SMRP to a closed state (switching from an open state to a closed state). In this way, the ECU 70 diagnoses whether or not the relay SMRB is welded. Specifically, when the voltage VH starts to rise, the ECU 70 diagnoses that the relay SMRB is welded. On the other hand, when the voltage VH does not rise as described above, the ECU 70 diagnoses that the relay SMRB is not welded. Note that the ECU 70 may switch the relay SMRG from an open state to a closed state instead of the relay SMRP.

[0052] Next, the ECU 70 switches the relay SMRP, which has been controlled to be in the closed state, to an open state, and then controls the relay SMRB to be in the closed state, whereby the ECU 70 similarly diagnoses whether or not either the relay SMRG or the relay SMRP is welded in accordance with the voltage VH.

[0053] When the ECU 70 diagnoses that neither the relay SMRG nor the relay SMRP is welded, the ECU 70 controls the relay SMRP to a closed state. As a result, in a situation where the current flowing through the capacitor 55 is limited by the limiting resistor 52, the pre-charging of the capacitor 55 is executed (started). When the voltage VH starts to rise, the ECU 70 determines the start of the pre-charging of the capacitor 55. Thereafter, when the voltage VH of the capacitor 55 rises to a threshold voltage, the ECU 70 determines the end of the pre-charging of the capacitor 55. The threshold voltage is a voltage at which the inrush current is reduced to a level that does not cause practical problems when external charging is started at the time when the voltage VH rises to the threshold voltage. In the present embodiment, the threshold voltage is appropriately determined in advance by an experiment or the like as a predetermined voltage equal to or lower than the voltage VB of the power storage device 5.

[0054] Next, the ECU 70 controls the relay SMRG to the closed state and the relay SMRP to the open state, thereby starting external charging in a situation where the inrush current is reduced.

[0055] As described above, before the start of external charging, the ECU 70 switches the open / closed states of the relays in the SMR 50. While the open / closed states of these relays are being switched, the ECU 70 determines whether these relays are welded and whether pre-charging of the capacitor 55 is being performed, according to the voltage VH.

[0056] While the vehicle 1 is parked, solar charging may be performed continuously during a period when the solar panel 90 can receive light from the sun. Therefore, a situation may often arise where a user who wishes to perform external charging connects (inserts) the connector 120 into the inlet 40 while solar charging is being performed. In such a situation, it is considered that the user wishes to perform external charging with a higher output than solar charging.

[0057] Here, if external charging is also started while solar charging is being performed, there is a possibility that it will not be possible to appropriately manage the charging power of the power storage device 5. Therefore, it is preferable that ECU 70 terminates solar charging and performs external charging when connector 120 is connected to inlet 40 (when a plugged-in state of vehicle 1 is detected).

[0058] When solar charging ends, the ECU 70 switches the SMR 50 from the on state to the off state in order to electrically disconnect the electric loads such as the PCU 20 from the power storage device 5. This causes the capacitor 55 to be discharged by the discharge resistor 56. Next, it appears preferable that the ECU 70 switches the relays SMRB, SMRP, and SMRG of the SMR 50 so that the capacitor 55 is pre-charged before the start of external charging in order to reduce the inrush current at the start of external charging. However, these relays wear out the more times they are switched.

[0059] Vehicle 1 according to the present embodiment has the following configuration to address the above problem. When external power source 110 is electrically connected to inlet 40 while solar charging is being performed, ECU 70 ends solar charging. ECU 70 executes pre-charge control to charge capacitor 55, which has been discharged following the end of solar charging, by using power generated by solar panel 90. Pre-charge control is control for charging capacitor 55 in advance before SMR 50 is turned on (e.g., before external charging is started). After executing pre-charge control, ECU 70 executes external charging by turning on SMR 50.

[0060] As a result, before the start of external charging, capacitor 55 is pre-charged using power generated by solar panel 90. Therefore, ECU 70 does not need to switch SMR 50 (more specifically, relay SMRP) to execute pre-charge control of capacitor 55 using power supplied from power storage device 5. As a result, the number of times SMR 50 is switched before the start of external charging is reduced. Therefore, wear of SMR 50 can be suppressed.

[0061] In particular, when the power generated by the solar panel 90 is equal to or greater than a threshold value when solar charging is terminated, it is preferable that the ECU 70 executes pre-charge control using the generated power. Then, after executing pre-charge control in this manner, the ECU 70 executes external charging by turning on the SMR 50. This makes it possible to effectively utilize the generated power without wasting it and suppress wear on the SMR 50 when the generated power is large enough to sufficiently charge the capacitor. In the following description, it is assumed that the ECU 70 executes external charging after executing pre-charge control in this manner.

[0062] Next, before describing in detail the switching control of the SMR 50 executed by the ECU 70 during the period from the end of solar charging to the start of external charging, a comparative example in which the switching control is not executed will be described.

[0063] Fig. 2 is a timing chart for explaining the control executed by the ECU of the comparative example from the end of solar charging to the start of external charging. In Fig. 2, the horizontal axis represents time. The vertical axis represents, from the top, on / off of solar charging, operation / stop of DC / DC converter 97, detection / non-detection of plug-in state, open / closed state of relay SMRB, open / closed state of relay SMRP, open / closed state of relay SMRG, voltage VH of capacitor 55, and on / off of external charging.

[0064] At time t0, the ECU performs solar charging of the vehicle 1 by driving the DC / DC converter 97 (lines 305 and 307). The ECU controls the relays SMRB and SMRG to a closed state (lines 315 and 325) while controlling the relay SMRP to an open state (line 320). During solar charging, the voltage VH of the capacitor 55 is equal to the voltage VB of the power storage device 5 (line 330).

[0065] At time t1, the ECU detects that the state of the vehicle 1 has switched to the plugged-in state based on the above-mentioned control pilot signal (line 310). When the ECU detects the switch to the plugged-in state, it terminates solar charging as described below in order to prioritize high-power external charging over solar charging.

[0066] At time t2, the ECU stops the solar charging (line 305) by stopping the DC / DC converter 97 of the solar unit 95 (line 307). In addition, the ECU switches the relays SMRB and SMRG from a closed state to an open state (lines 315 and 325). This causes the capacitor 55 to start discharging through the discharge resistor 56. As a result, the voltage VH of the capacitor 55 starts to decrease and becomes 0 at time t3 (line 330).

[0067] At time t4, the ECU switches relay SMRP from an open state to a closed state (line 320) to diagnose whether relay SMRB is welded. The ECU maintains relay SMRP in the closed state during the period from time t4 to time t5. In the example of FIG. 2, since voltage VH does not change, the ECU diagnoses that relay SMRB is not welded. Therefore, at time t5, the ECU switches relay SMRP from a closed state to an open state.

[0068] At time t6, the ECU switches the relay SMRB from the open state to the closed state in order to diagnose whether or not at least one of the relays SMRG and SMRP is welded. In the example of Fig. 2, since the voltage VH does not change, the ECU diagnoses that neither the relay SMRG nor the relay SMRP is welded.

[0069] At time t7, the ECU starts pre-charging control of the capacitor 55 using the power supplied from the power storage device 5. Specifically, the ECU switches the relay SMRP from the open state to the closed state. As a result, a current starts to flow from the power storage device 5 to the capacitor 55 in a situation where the current is limited by the limiting resistor 52. As a result, the voltage VH of the capacitor 55 starts to rise (line 330).

[0070] At time t8, when the voltage VH reaches the threshold voltage VTH, the ECU determines that the pre-charging of the capacitor 55 is completed. Then, the ECU switches the relay SMRG from the open state to the closed state. This starts external charging (line 335). After time t8, the voltage VH rises to the voltage VB, and the relay SMRP is switched from the closed state to the open state (time t9).

[0071] 2, the ECU opens and closes relay SMRP during the period for the welding diagnosis (time t4 to time t5). Furthermore, the ECU controls relay SMRP to the closed state during the period for precharging capacitor 55 (time t7 to time t8), and then switches it to the open state. That is, the ECU opens and closes relay SMRP twice (line 320) from the end of solar charging to the start of external charging.

[0072] FIG. 3 is a timing chart for illustrating switching control of the SMR 50 executed by the ECU 70 during the period from the end of solar charging to the start of external charging in this embodiment.

[0073] 3, the horizontal axis represents time, and the vertical axis represents, from the top, on / off of solar charging, operation / stop of DC / DC converter 97, detection / non-detection of a plugged-in state, the open / closed state of relay SMRB, the open / closed state of relay SMRP, the open / closed state of relay SMRG, voltage VH of capacitor 55, and on / off of external charging.

[0074] In this embodiment, the control by the ECU 70 from time t10 to time t16 is similar to the control from time t0 to time t6 in the comparative example (FIG. 2) described above. Specifically, upon detection of the switch to the plugged-in state (line 410), the ECU 70 ends solar charging (line 405), discharges the capacitor 55, and completes the diagnosis of welding of the relays SMRB, SMRP, and SMRG.

[0075] At time t17, the ECU 70 calculates the power generated by the solar panel 90 (the input power to the DC / DC converter 97) according to the detection values ​​of the voltage sensor 91 and the current sensor 92, and judges whether the generated power is equal to or greater than a threshold value. The threshold value is appropriately determined in advance as a value at which, when power equal to or greater than the threshold value is input to the DC / DC converter 97, the voltage VH can be increased to the threshold voltage VTH within a predetermined time by the converted power. The length of the predetermined time is appropriately determined in advance so as to maintain user convenience. In the example of FIG. 2, it is assumed that the generated power is equal to or greater than the threshold value. Therefore, the ECU 70 executes precharge control of the capacitor 55 using the generated power by the solar panel 90. Specifically, the ECU 70 activates the DC / DC converter 97 (line 407). As a result, the converted power starts to be supplied from the DC / DC converter 97 to the positive line PL and the negative line NL, and the capacitor 55 starts to be charged. As a result, the voltage VH starts to rise (line 430). Thus, in the present embodiment, unlike the comparative example (time t7 to time t9 in FIG. 2), ECU 70 can increase voltage VH without switching relay SMRP from the open state to the closed state before the start of external charging.

[0076] At time t18, when the voltage VH reaches the threshold voltage VTH, the ECU 70 determines the end of the precharging of the capacitor 55. Then, the ECU 70 starts external charging (line 435) by controlling the relays SMRB and SMRG to the closed state (lines 415 and 425) while controlling the relay SMRP to the open state (line 420).

[0077] In the present embodiment, similarly to the comparative example (FIG. 2), the ECU 70 opens and closes the relay SMRP during the period for the welding diagnosis (time t14 to time t15). On the other hand, unlike the comparative example, the ECU 70 pre-charges the capacitor 55 using power generated by the solar panel 90 during the period from time t17 to time t18 before external charging. Therefore, the ECU 70 does not need to open and close the relay SMRP during this period. Therefore, although the ECU 70 opens and closes the relay SMRP for the welding diagnosis during the period from the end of solar charging to the start of external charging, the number of times that the relay SMRP is opened and closed is one (line 420).

[0078] Therefore, in the present embodiment, the number of times that the ECU 70 switches the open / closed state of the relay SMRP is less than the two times (line 320) in the comparative example. As a result, it is possible to reduce the inrush current that occurs when external charging starts after solar charging is performed, while suppressing wear of the relay SMRP.

[0079] In the above description, the timing at which the ECU 70 determines whether the generated power is equal to or greater than the threshold value is time t17, but is not limited to this time. The ECU 70 may determine whether the generated power is equal to or greater than the threshold value when solar charging is terminated (within a predetermined period between time t12, which is the end time of solar charging, and time t17).

[0080] Fig. 4 is a flowchart showing an example of a process associated with solar charging and external charging. In the following description, Fig. 3 will be referred to as appropriate. This flowchart is executed when solar charging is being performed. Note that while solar charging is being performed, relays SMRB and SMRG are controlled to be in a closed state, while relay SMRP is controlled to be in an open state.

[0081] In step S105, the ECU 70 determines whether or not the external power source 110 is electrically connected to the inlet 40. If the external power source 110 is not connected to the inlet 40 (NO in step S105), the ECU 70 executes this determination process until the external power source 110 is connected to the inlet 40. On the other hand, if the external power source 110 is connected to the inlet 40 (YES in step S105), the ECU 70 detects the connection (time t11) and proceeds to the process of step S107.

[0082] Next, the ECU 70 stops the DC / DC converter 97 (step S107) and switches the relays SMRB and SMRG from the closed state to the open state (step S110). This ends the solar charging (time t12), and the capacitor 55 is discharged by the discharge resistor 56 (time t12 to time t13).

[0083] Thereafter, the ECU 70 opens and closes the relay SMRP in order to diagnose whether or not the relay SMRB is welded (time t14 to time t15). In step S115, the ECU 70 switches the relay SMRB from an open state to a closed state in order to diagnose whether or not at least one of the relays SMRG and SMRP is welded (time t16).

[0084] In step S120, the ECU 70 calculates the power generated by the solar panel 90. Then, in step S125, the ECU 70 determines whether the generated power is equal to or greater than a threshold value.

[0085] If the generated power is equal to or greater than the threshold value (YES in step S125), ECU 70 proceeds to step S130. In step S130, ECU 70 starts up DC / DC converter 97 (time t17). This causes power to start being supplied from DC / DC converter 97 to capacitor 55, so that voltage VH starts to increase. After that, ECU 70 proceeds to step S140.

[0086] On the other hand, if the generated power is less than the threshold value (NO in step S125), the ECU 70 proceeds to step S135. In step S135, the ECU 70 executes normal pre-charge control. The "normal pre-charge control" refers to controlling the relay SMRB to the closed state while controlling the relay SMRP to the closed state in a situation where the capacitor 55 is discharged. As a result, in a situation where the current is limited by the limiting resistor 52, power begins to be supplied from the power storage device 5 to the capacitor 55, and the voltage VH begins to rise. In this way, even if the generated power by the solar panel 90 is not large enough to sufficiently charge the capacitor 55, the pre-charge control is executed using the power supplied from the power storage device 5. After step S135, the ECU 70 proceeds to step S140.

[0087] In step S140, the ECU 70 determines whether the voltage VH has reached the threshold voltage VTH according to the detection value of the voltage sensor 60. If the voltage VH has not reached the threshold voltage VTH (NO in step S140), the ECU 70 executes this determination process until the voltage VH reaches the threshold voltage VTH (while the process branches to NO in step S140). On the other hand, if the voltage VH has reached the threshold voltage VTH (YES in step S140), the ECU 70 switches the relay SMRG from an open state to a closed state (step S145). This starts external charging in a situation where the inrush current is reduced (time t18). Note that, if the process of step S135 has been executed, the ECU 70 further switches the relay SMRP from a closed state to an open state after the process of step S145.

[0088] As described above, in the present embodiment, the ECU 70 ends solar charging when the external power source 110 is electrically connected to the inlet 40 while solar charging is being performed. The ECU 70 executes pre-charge control to charge the capacitor 55 that was discharged when solar charging was terminated, using the power generated by the solar panel 90. After executing the pre-charge control, the ECU 70 then executes external charging by turning on the SMR 50.

[0089] As a result, before the start of external charging, capacitor 55 is pre-charged using power generated by solar panel 90. Therefore, ECU 70 does not need to switch SMR 50 (more specifically, relay SMRP) to execute pre-charge control of capacitor 55 using power supplied from power storage device 5. As a result, the number of times SMR 50 is switched before the start of external charging is reduced. Therefore, wear of SMR 50 can be suppressed.

[0090] Furthermore, according to this embodiment, when external power supply 110 is electrically connected to inlet 40 during solar charging, solar charging is terminated. This makes it possible to prevent solar charging and external charging from being performed simultaneously. This makes it possible to avoid a situation in which the charging power of power storage device 5 cannot be appropriately managed.

[0091] [Variation 1] In the above embodiment, the ECU 70 determines whether or not to execute pre-charge control, which charges the capacitor 55 that has been discharged upon completion of solar charging, using power generated by the solar panel 90, according to the detection values ​​of the voltage sensor 91 and the current sensor 92. Alternatively, the ECU 70 may execute the above determination process according to sunlight information for the current position of the vehicle 1 acquired by the communication device 250. As described above, the sunlight information is information that indicates the amount of sunlight at the current position, and information that indicates the weather (for example, whether the weather is sunny, cloudy, or rainy), etc.

[0092] The ECU 70 acquires the amount of solar radiation at the current position of the vehicle 1 from, for example, a weather forecast site through the network 300 and the communication device 250. Here, the greater the amount of solar radiation, the greater the power generated by the solar panel 90. Therefore, the ECU 70 may determine whether or not to execute pre-charge control using the power generated by the solar panel 90 according to whether or not the amount of solar radiation is equal to or greater than a predetermined threshold. Alternatively, the ECU 70 calculates the power generated according to the amount of solar radiation at the current position using a map that predefines the relationship between the amount of solar radiation and the power generated. This map is stored, for example, in the ROM of the ECU 70. The ECU 70 may determine whether or not to execute pre-charge control using the power generated by the solar panel 90 according to the power generated calculated using the map.

[0093] The ECU 70 may obtain weather information for the current location of the vehicle 1 from a weather forecast site through the network 300 and the communication device 250. For example, when the weather is fine, the ECU 70 can perform solar charging. In this case, the ECU 70 performs pre-charge control using power generated by the solar panel 90.

[0094] On the other hand, for example, when the weather is cloudy, rainy, or snowy, the ECU 70 cannot execute solar charging, and therefore in this case, the ECU 70 executes normal pre-charge control before starting external charging.

[0095] As described above, according to this modification, even if the solar unit 95 is not provided with the voltage sensor 91 and the current sensor 92, the ECU 70 can determine whether or not to execute pre-charge control using the power generated by the solar panel 90 after discharging the capacitor 55. As a result, when the pre-charge control is executed using the generated power, the number of times the open / closed state of the relay SMRP is switched before the start of external charging can be reduced compared to the comparative example (FIG. 2).

[0096] [Variation 2] In the above-described embodiment and the first modified example thereof, ECU 70 performs contact charging, in which power storage device 5 is charged using power supplied from external power supply 110 through inlet 40, as external charging.

[0097] On the other hand, when the vehicle 1 includes a non-contact power receiving device as a power receiving unit, the ECU 70 may be configured to perform non-contact charging for charging the power storage device 5 according to a non-contact charging method. Specifically, when the power supply equipment 100 includes a non-contact power transmitting device, the non-contact power receiving device of the vehicle 1 receives power from the power supply equipment 100 by being electromagnetically coupled to the power transmitting device. The ECU 70 turns on the SMR 50 so that the power received by the power receiving device is charged to the power storage device 5. This performs non-contact charging.

[0098] The ECU 70 ends solar charging when the external power source 110 is electrically connected to the power receiving device through the power transmitting device while solar charging is being performed. The subsequent processing is similar to the processing by the ECU 70 described with reference to Figures 3 and 4. In this way, the mode of external charging is not limited to contact charging, and may include non-contact charging.

[0099] [Variation 3] In the above-described embodiment and its modifications 1 and 2, capacitor 55 is discharged by discharge resistor 56 after solar charging is completed.

[0100] In response to this, the ECU 70 may discharge the capacitor 55 by controlling the MG 25 to consume power without outputting torque. Specifically, the ECU 70 may control the switching elements of the PCU 20 so that a current flows in the direction of a magnetic flux formed in the rotor of the MG 25. When the capacitor 55 is discharged in this manner, the discharge resistor 56 does not need to be provided. In this case, it is possible to avoid power loss in the discharge resistor 56 during solar charging and external charging.

[0101] [Variation 4] The ECU 70 may determine whether the power generated by the solar panel 90 is equal to or greater than a threshold value according to whether the rate of increase in the SOC of the power storage device 5 when the solar charging is terminated is a predetermined threshold rate. The rate of increase in the SOC of the power storage device 5 is related to the power generation. Specifically, the greater the power generated by the solar panel 90, the greater the power after conversion by the DC / DC converter 97, and therefore the rate of increase in the SOC of the power storage device 5. Therefore, when the rate of increase in the SOC that makes the power generation equal to or greater than the above-mentioned threshold value is appropriately determined in advance by an experiment or the like, the ECU 70 may determine whether the power generation is equal to or greater than a threshold value according to the rate of increase in the SOC of the power storage device 5. In this way, even if the voltage sensor 91, the current sensor 92, and the communication device 250 are not provided, the ECU 70 can determine whether to execute pre-charge control using the generated power.

[0102] [Variation 5] In the above-described embodiment and its modified examples 1 to 4, the solar unit 95 and the external charging mechanism (charging device 200, relay 59, and inlet 40) are connected to the pair of power lines (positive line PL and negative line NL) between the SMR 50 and the PCU 20. In contrast, in this modified example, the solar unit 95 and the external charging mechanism are connected to the power storage device 5 side via a charging relay 50A (described later).

[0103] Fig. 5 is a diagram that illustrates a schematic configuration of a vehicle according to Modification 5. With reference to Fig. 5, vehicle 2 includes a charging relay 50A. Charging relay 50A includes relays RYB, RYP, and RYG, and a limiting resistor 52A. Relay RYB is connected to a positive electrode line PLA. Relay RYG is connected to a negative electrode line NLA. Relay RYP and limiting resistor 52A connected in series therewith are connected in parallel to relay RYG.

[0104] A capacitor 55A and a discharge resistor 56A connected in parallel thereto are provided between a power line pair including a positive electrode line PLA and a negative electrode line NLA. The solar unit 95 and the external charging mechanism are connected in parallel to this power line pair.

[0105] In this modification, similarly to the case of the above-described embodiment, the ECU 70 terminates solar charging when the external power source 110 is electrically connected to the inlet 40 while solar charging is being performed. The ECU 70 executes pre-charge control for charging the capacitor 55A that has been discharged as the solar charging is terminated, using power generated by the solar panel 90. This pre-charge control is control for charging the capacitor 55A in advance before the charging relay 50A is turned on (for example, before external charging is started). After executing the pre-charge control, the ECU 70 executes external charging by turning on the charging relay 50A.

[0106] Note that the "off state" of charging relay 50A is a state in which relays RYB, RYG, and RYP are open. The "on state" of charging relay 50A is a state in which relays RYB and RYG are closed. To "turn on" charging relay 50A is to switch charging relay 50A from an off state to an on state. To "turn off" charging relay 50A is to switch charging relay 50A from an on state to an off state.

[0107] By executing the pre-charge control using the above-described generated power, the ECU 70 does not need to switch the charging relay 50A (more specifically, the relay RYP) to execute normal pre-charge control of the capacitor 55A using the power supplied from the power storage device 5. As a result, similar to the SMR 50 of the above-described embodiment, the number of times the charging relay 50A is switched before the start of external charging is reduced. Therefore, according to this modification, it is possible to suppress wear of the charging relay 50A more than when normal pre-charge control of the charging relay 50A is executed. Note that the "normal pre-charge control" of the charging relay 50A refers to controlling the relay RYB to the closed state and the relay RYP to the closed state in a situation where the capacitor 55A is discharged.

[0108] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0109] 5 Energy storage device, 40 Inlet, 52 Limiting resistor, 55 Capacitor, 56 Discharge resistor, SMRB, SMRG, SMRP Relay, 90 Solar panel, 93 Power line, 95 Solar unit, 97 DC / DC converter, 100 Power supply equipment, 110 External power supply, 200 Charging device, 250 Communication device.

Claims

1. A power storage device; a power receiving unit configured to receive power from an external power source provided outside the vehicle; a relay unit provided in a power line pair between the power storage device and the power receiving unit; a capacitor provided between the power line pair and between the relay unit and the power receiving unit; a solar cell connected to the power line pair between the relay unit and the power receiving unit, the solar cell receiving the light energy and generating electricity; a control device configured to execute solar charging for charging the power storage device using power generated by the solar cell, and external charging for charging the power storage device using power supplied from the external power source through the power receiving unit, When the external power source is electrically connected to the power receiving unit during the solar charging, the control device Terminate the solar charging. executing a pre-charge control for charging the capacitor that has been discharged following completion of the solar charging, using the generated power; After the precharge control is performed, the relay unit is turned on to perform the external charging.

2. The relay unit includes: a first relay provided on one of the pair of power lines; a second relay provided on the other of the pair of power lines; a precharge circuit connected in parallel to the second relay; The precharge circuit includes: A third relay; and a limiting resistor connected in series with the third relay; The control device includes: The first relay, the second relay, and the third relay are controlled to an open state, and the solar charging is terminated; The vehicle according to claim 1 , wherein after the pre-charge control is performed, the external charging is performed by controlling the first relay and the second relay to a closed state while controlling the third relay to an open state.

3. 3. The vehicle according to claim 1, wherein, when the generated power is equal to or greater than a threshold value when the solar charging is terminated, the control device executes the pre-charge control using the generated power.

4. 4. The vehicle according to claim 3, wherein when the generated power is less than the threshold value when the solar charging is terminated, the control device controls the relay unit to perform the pre-charge control using the power supplied from the power storage device.

5. a communication device that acquires sunlight information indicating a sunlight irradiation state at a current position of the vehicle through communication; 5. The vehicle according to claim 1, wherein the control device determines whether or not to execute the pre-charge control using the generated power in accordance with the insunshine information.

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