Vehicle controller

Abstract

To prevent a charging relay from reaching high temperatures.SOLUTION: When a vehicle is running and a charging lid is closed, at least one of a first charging relay and a second charging relay is turned ON. If the charging lid is opened after at least one of the first charging relay and the second charging relay was turned ON, or if a predetermined duration has passed after at least one of the first charging relay and the second charging relay was turned ON in the relay-on process, the relay that is in an ON state between the first charging relay and the second charging relay is turned OFF.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a vehicle control device. [Background technology]

[0002] Conventionally, a vehicle control device of this type has been proposed that is used in a vehicle equipped with a motor for driving, an inverter for driving the motor, a power storage device (secondary battery) that exchanges power with the motor via the inverter, and a relay attached via a bus bar to a driving power line between the inverter and the power storage device, and controls the relay (see, for example, Patent Document 1). The relay includes a first charging relay that is attached via a first bus bar to the positive line of the driving power line and includes a first relay contact that closes when the first exciting coil is excited, and a second charging relay that is attached via a second bus bar to the negative line of the driving power line and includes a second relay contact that closes when the second exciting coil is excited. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-079093 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a vehicle having a charging inlet that is connectable to a charging connector of an external power source and is connected to a power storage device via a power line, in a vehicle in which the above-mentioned relay is attached to the power line between the charging inlet and the power storage device, the relay is turned off while the vehicle is running, i.e., the first and second relay contacts of the first and second charging relays are separated from the power line. When the first and second relay contacts are separated, the charging relay may reach a high temperature.

[0005] The main object of the vehicle control device disclosed herein is to prevent the charging relay from reaching a high temperature. [Means for solving the problem]

[0006] The vehicle control device of the present disclosure employs the following means to achieve the above-mentioned main object: The vehicle control device of the present disclosure includes a motor for driving, a power storage device that exchanges power with the motor, a charging inlet that is connectable to a charging connector of an external power source and is connected to the power storage device, an openable and closable charging lid that exposes and closes the charging inlet, a first charging relay including a first relay contact that is connected to a positive line of a driving power line between the motor and the power storage device and to a positive line of a charging power line from the charging lid and that closes when a first exciting coil is excited, and a second charging relay including a second relay contact that is connected to a negative line of the driving power line and to a negative line of the charging power line and that closes when a second exciting coil is excited. and a charging relay having a first charging relay and a second charging relay having a second charging relay, and the vehicle control device controls at least the charging relay, wherein when the vehicle is traveling and the charging lid is closed, at least one of the first charging relay and the second charging relay is turned on, and when the charging lid is opened after turning on at least one of the first charging relay and the second charging relay, or when a predetermined time has elapsed since turning on at least one of the first charging relay and the second charging relay, the first charging relay and the second charging relay that are turned on are turned off. [Brief description of the drawings]

[0007] [Figure 1] 1 is a diagram showing an outline of the configuration of an electric vehicle 20. FIG. [Diagram 2] 4 is a flowchart showing an example of a relay control routine. [Diagram 3] 4 is a flowchart showing an example of a post-ON control routine. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] An embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a schematic diagram showing the configuration of an electric vehicle 20 equipped with a vehicle control device of the present embodiment. As shown in the figure, the electric vehicle 20 of the embodiment includes a motor 32 for driving, an inverter 34, a battery 36 as an electricity storage device, a charging inlet 56, a charging lid 57, a charging relay 58, and an electronic control unit (hereinafter referred to as "ECU") 70. The motor 32 is configured as a synchronous generator motor, and includes a rotor in which a permanent magnet is embedded, and a stator around which a three-phase coil is wound. The rotor of the motor 32 is connected to a drive shaft 26 that is connected to the drive wheels 22a, 22b via a differential gear 24. The inverter 34 is connected to a drive power line 35 (positive line 35a, negative line 35b). The inverter 34 is configured as a well-known inverter circuit having six transistors and six diodes, and drives the motor 32. A capacitor 44 is connected to the positive line 35a and the negative line 35b of the drive power line 35. The battery 36 is configured as, for example, a lithium ion secondary battery or a nickel-hydrogen secondary battery, and is connected to the drive power line 35 via a system main relay (SMR) 38.

[0009] Charging inlet 56 is disposed in a lid box provided at a charging port (opening) of electric vehicle 20. Charging inlet 56 is configured to allow a charging connector on the external power supply side connected via a charging cable to be attached / detached. When charging inlet 56 is connected to the external power supply via the charging cable, DC power from the external power supply is supplied to charging power lines 50 (positive electrode line 50a, negative electrode line 50b). Charging lid 57 is attached to the vehicle body via a hinge mechanism, for example, and is configured to be able to switch between exposing and closing the charging port (opening) in which charging inlet 56 is disposed by opening and closing it.

[0010] The charging relay 58 includes a first relay and a second relay (first and second charging relays) DCRB and DCRG. The first relay DCRB includes a first exciting coil 580, a first relay contact 582, a first power line bus bar 584, and a first charging bus bar 586. The first exciting coil 580 is a conductor coated with enamel having high insulating properties as an insulating material, and an exciting current is supplied to the first exciting coil 580 by the ECU 70. The first relay contact 582 includes terminals 582a and 582b as fixed contacts, a movable contactor 582c as a movable contact, an iron core 582d, and a coil 582e. The terminal 582a is connected to the first power line bus bar 584. The first power line bus bar 584 is connected to the positive electrode line 35a of the drive power line 35. The terminal 582b is connected to the first charging bus bar 586. The first charging bus bar 586 is connected to the positive line 50a of the charging power line 50. The first power line bus bar 584 and the first charging bus bar 586 are formed as plate-shaped metal members with good electrical conductivity and thermal conductivity, and are cooled by a water-cooling type cooling device (not shown). The first excitation coil 580 is wound around the iron core 582d. The first excitation coil 580, the movable contact 582c, the iron core 582d, and the coil 582e are housed in a first relay case 590 formed in a cube shape. In the first relay DCRB, when an excitation current is applied to the first excitation coil 580, the iron core 582d is magnetized by the first excitation coil 580, and as shown by the broken line, the movable contact 582c is attracted upward by the electromagnetic force generated in the iron core 582d, and the movable contact 582c comes into contact with the terminals 582a and 582b. As a result, the first relay contact 582 is closed and the first relay DCRB is turned on. On the other hand, when no excitation current is applied to the first excitation coil 580, the electromagnetic force of the iron core 582d disappears, and the movable contactor 582c is separated from the terminals 582a and 582b. As a result, the first relay contactor 582 is opened and the first relay DCRB is turned off. Although not shown, the second relay DCRG has the same configuration as the first excitation coil 580, and includes a second excitation coil, a second relay contactor, a second power line bus bar, and a second charging bus bar. The second relay contactor includes two terminals as fixed contacts, a movable contactor, an iron core, and a coil as movable contacts.One of the two terminals is connected to the second power line bus bar. The second power line bus bar is connected to the negative line 35b of the driving power line 35. The other of the two terminals is connected to the second charging bus bar. The second charging bus bar is connected to the negative line 50b of the charging power line 50. The second power line bus bar and the second charging bus bar are configured as plate-shaped metal members with good electrical conductivity and thermal conductivity, and are cooled by a water-cooling type cooling device (not shown). The second excitation coil is wound around the iron core. The second excitation coil, the movable contact, the iron core, and the coil are housed in a second relay case formed in a cube shape. In the second relay DCRG, similar to the first relay DCRB, when an excitation current is applied to the second excitation coil, the movable contact comes into contact with the two terminals, thereby closing the second relay contact and turning on the second relay DCRG. On the other hand, when no excitation current is applied to the second excitation coil, the movable contactor is separated from the two terminals, whereby the second relay contact opens and the second relay DCRG is turned off.

[0011] The ECU 70 is configured as a microprocessor centered on a CPU (not shown), and in addition to the CPU, includes a ROM, a RAM, and input / output ports and communication ports (not shown). Signals from various sensors are input to the ECU 70 via an input port. Examples of signals input to the ECU 70 include an opening / closing signal Lo from an opening / closing sensor 57a that detects the opening / closing of the charging lid 57 and a vehicle speed V from a vehicle speed sensor 60 that detects the vehicle speed. Since the ECU 70 also functions as a drive control device for the vehicle, information necessary for driving control is also input to the ECU 70. Various control signals are output from the ECU 70 via an output port. Examples of signals output from the ECU 70 include a switching control signal to the transistor of the inverter 34, and an excitation current to the system main relay 38 and the first and second relays DCRB and DCRG.

[0012] In the electric vehicle 20 thus configured, when the ECU 70 turns on the system (system start-up) and runs, the ECU 70 turns on the system main relay 38 and turns off the first and second relays DCRB and DCRG, and supplies power from the battery 36 to the motor 32 via the system main relay 38, the driving power line 35 (positive line 35a, negative line 35b), and the inverter 34, and runs with power from the motor 32. When the ECU 70 turns off the system (system stop) and stops the vehicle, the ECU 70 stops driving the inverter 34 and turns off the system main relay 38. When the charging lid 57 is opened while the system is off and the charging inlet 56 is connected to an external power source via a charging cable, the ECU 70 turns on the system main relay 38 and turns on the charging relay 58 (first and second relays DCRB and DCRG), and supplies DC power from the external power source to the battery 36 via the charging power line 50 (positive line 50a, negative line 50b) to charge the battery 36. When the battery 36 is sufficiently charged, the system main relay 38 is turned off, the first and second relays DCRB, DCRG are turned off, the charging cable is unplugged from the charging inlet 56, and the charging lid 57 is closed, thereby terminating charging of the battery 36 with DC power from the external power source.

[0013] Next, the operation of the electric vehicle 20 thus configured, particularly the operation when preventing the charging relay 58 from reaching a high temperature, will be described. Fig. 2 is a flowchart showing an example of a relay control routine executed by the ECU 70. The relay control routine is repeatedly executed at predetermined time intervals tref1 (e.g., several msec) while the vehicle is running after the system is turned on.

[0014] When the relay control routine is executed, the CPU of the ECU 70 executes a process of inputting the vehicle speed V from the vehicle speed sensor 60 and the opening / closing signal Lo from the opening / closing sensor 57a (S100). When the vehicle speed V and the opening / closing signal Lo are input, the ECU 70 determines whether the charging lid 57 is closed (S110), whether the vehicle speed V is equal to or greater than a predetermined vehicle speed Vref (S120), and whether the second relay DCRG is off (S130). In S120, the predetermined vehicle speed Vref is a threshold value for determining whether the electric vehicle 20 is traveling, and is set to, for example, 10 km / h, 20 km / h, 30 km / h, or the like. When the charging lid 57 is closed in S110, the vehicle speed V is equal to or greater than the predetermined vehicle speed Vref in S120, and the second relay DCRG is off in S130, the charging lid 57 is closed, the electric vehicle 20 is running, and no current flows through the charging power line 50 even if the first relay DCRB is turned on. Therefore, it is determined that no inconvenience such as electric shock will occur even if the first relay DCRB is turned on, and an excitation current is applied to the first exciting coil 580 so that the first relay DCRB is turned on (S140), and the relay control routine is terminated. When the first relay DCRB is turned on, the movable contact 582c comes into contact with the terminals 582a and 582b, so that heat can be dissipated from within the first relay case 590 via the first power line bus bar 584 and the first charging bus bar 586. This makes it possible to prevent the first relay DCRB, and therefore the charging relay 58, from reaching a high temperature.

[0015] When the charging lid 57 is open in step S110, or when the charging lid 57 is closed in S110 but the vehicle speed V is less than the predetermined vehicle speed Vref in S120, or when the charging lid 57 is closed in S110 and the vehicle speed V is equal to or greater than the predetermined vehicle speed Vref in S120 but the second relay DCRG is on in S130, it is determined that turning on the first relay DCRB may cause an inconvenience such as electric shock, and the application of the excitation current to the first exciting coil 580 is stopped so that the first relay DCRB is turned off (S150), and this routine is terminated. Note that when the first relay DCRB is off immediately before executing S150, S150 is a process of continuing to turn off the first relay DCRB. This makes it possible to more reliably prevent inconvenience such as electric shock from occurring.

[0016] Next, a process after the first relay DCRB is turned on in S140 will be described. Fig. 3 is a flowchart showing an example of a post-on control routine executed by the ECU 70. The post-on control routine is executed every predetermined time tref2 (e.g., several msec) after the first relay DCRB is turned on in S140. Note that the predetermined time tref2 may be the same as or different from the predetermined time tref1.

[0017] When the post-on control routine is executed, the CPU of the ECU 70 executes a process of inputting the elapsed time ts and the opening / closing signal Lo detected by the opening / closing sensor 57a (S200). The elapsed time ts is the time elapsed since the first relay DCRB was turned on in S140, and is inputted as measured by a timer built into the CPU of the ECU 70. The elapsed time ts is reset to a value of 0 when the first relay DCRB is turned off in S150.

[0018] Next, in the same process as in S110, it is determined whether charging lid 57 is closed (S210) and whether elapsed time ts has exceeded predetermined time tsref (S220). Predetermined time tsref is a threshold value for determining whether heat dissipation from first relay DCRB via first power line bus bar 584 and first charging bus bar 586 by turning on first relay DCRB has been sufficiently performed.

[0019] When charging lid 57 is open in S210, it is determined that continuing to turn on first relay DCRB may cause inconvenience such as electric shock, and when charging lid 57 is closed in S210 and the elapsed time ts has exceeded the predetermined time tsref, it is determined that heat dissipation from first relay DCRB has been sufficient, and the first relay DCRB is turned off (S230) and this routine is terminated. This makes it possible to prevent inconvenience such as electric shock and to prevent the first relay DCRB from being turned on for long periods of time while driving.

[0020] When the charging lid 57 is closed in S210, that is, when continuing to turn on the first relay DCRB will not cause any inconvenience such as electric shock, and when the elapsed time ts has not reached the predetermined time tsref, that is, when the heat dissipation of the first relay DCRB is insufficient, this routine ends. By carrying out such processing, the heat dissipation of the first relay DCRB continues, and therefore the first relay DCRB, and therefore the charging relay 58, can be prevented from reaching a high temperature.

[0021] According to the electric vehicle 20 equipped with the vehicle control device of the present embodiment described above, when the vehicle is traveling and the charging lid 57 is closed, the first relay DCRB is turned on, and when the charging lid 57 is opened after the first relay DCRB is turned on or when the elapsed time ts exceeds a predetermined time tsref, the first relay DCRB is turned off, thereby preventing the charging relay 58 from reaching a high temperature.

[0022] In the above-described embodiment, it is confirmed in S130 that the second relay DCRG is off, and then the first relay DCRB is turned on in S140. However, it is also possible to confirm in S130 that the first relay DCRB is off, and then turn on the second relay DCRG in S140, or to turn on the first relay DCRB and the second relay DCRG in S140 without executing S130.

[0023] Note that the correspondence between the main elements of the embodiment and the main elements of the invention described in the Means for Solving the Problem column does not limit the elements of the invention described in the Means for Solving the Problem column, since the embodiment is an example for specifically explaining the form for implementing the invention described in the Means for Solving the Problem column. In other words, the interpretation of the invention described in the Means for Solving the Problem column should be made based on the description in that column, and the embodiment is merely a specific example of the invention described in the Means for Solving the Problem column.

[0024] The above describes embodiments for implementing the present disclosure, but the present disclosure is not limited to these embodiments, and it goes without saying that the present disclosure can be implemented in various forms without departing from the gist of the present disclosure. [Industrial Applicability]

[0025] The present disclosure can be used in the vehicle control device manufacturing industry and the like. [Explanation of symbols]

[0026] 20 Electric vehicles, 58 Charging relays.

Claims

[Claim 1] a charging relay including: a first charging relay including a first relay contact connected to a positive line of a driving power line between the motor and the power storage device and to a positive line of a charging power line from the charging lid, the first relay contact being connected to a positive line of a driving power line between the motor and the power storage device and to a positive line of a charging power line from the charging lid and closing when a first exciting coil is excited; and a second charging relay including a second relay contact connected to a negative line of the driving power line and to a negative line of the charging power line and closing when a second exciting coil is excited. A vehicle control device is used in a vehicle including: a driving motor; When the vehicle is traveling and the charging lid is closed, at least one of the first charging relay and the second charging relay is turned on; When the charging lid is opened after at least one of the first charging relay and the second charging relay is turned on, or when a predetermined time has elapsed after at least one of the first charging relay and the second charging relay is turned on, the first charging relay and the second charging relay that are turned on are turned off. Vehicle control device.

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