Power management device for electric vehicles

Abstract

This electric vehicle power supply management device is provided with a contactor for electrically connecting or disconnecting a drive battery to or from an auxiliary machine battery and comprises: an auxiliary machine charging management unit provided with a request determination unit that outputs a request for connection by the contactor for a predetermined charging period when a predetermined timing is reached; and a connection management unit provided with a charging execution determination unit that determines whether the connection by the contactor is possible or not when the request for the connection by the contactor is received and a count unit that counts the number of times the charging execution determination unit has determined that the connection is impossible. The auxiliary machine charging management unit has a timing change unit that shortens the period until the predetermined timing as the number of times counted by the count unit increases.

Description

[Technical Field]

[0001] The present disclosure relates to a power management device for an electric vehicle. [Background technology]

[0002] Patent Document 1 discloses an electric vehicle equipped with a drive battery that supplies power to a traction motor driven by high voltage and an auxiliary battery that supplies power to auxiliary devices driven by low voltage. If an electric vehicle equipped with such a drive battery and auxiliary battery is left unattended, the stored power of the auxiliary battery will gradually decrease. For this reason, the auxiliary battery is electrically connected to the drive battery at predetermined intervals and a DC-DC converter is activated to supply power from the drive battery to the auxiliary battery and charge the auxiliary battery (charging the auxiliary battery at predetermined intervals in this manner is called "periodic auxiliary charging"). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-164494 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if the electric vehicle is left unattended and periodic auxiliary charging is not repeatedly performed for some reason, the stored power in the auxiliary battery will eventually become insufficient, and the electric vehicle will no longer be able to start.

[0005] In view of the above circumstances, at least one embodiment of the present invention aims to provide a power management device for an electric vehicle that can reduce the frequency of an electric vehicle being unable to start due to a shortage of stored power in an auxiliary battery. [Means for solving the problem]

[0006] (1) At least one embodiment of the present invention provides a power supply management device for an electric vehicle that includes a contactor that electrically connects or disconnects a drive battery and an auxiliary battery, the power supply management device including an auxiliary charging management unit that includes a request determination unit that outputs a connection request for the contactor for a predetermined charging period at a predetermined timing, and a request determination unit that, when the connection request for the contactor is input, determines whether or not the auxiliary battery is connected. Based on opening / closing information of the opening / closing member of the electric vehicle The connection management unit is provided with a charging execution determination section that determines whether the contactor can be connected or not, and a counting section that counts the number of times the charging execution determination section determines that connection is not possible, and the auxiliary equipment charging management unit has a timing change section that shortens the period until the predetermined timing as the number of times counted by the counting section increases.

[0007] According to the configuration (1) above, the period until the predetermined timing is shortened as the number of times counted by the counting unit increases, so that the timing to start charging (regular auxiliary charging) is advanced, and the frequency of the electric vehicle being unable to start due to a shortage of stored power in the auxiliary battery can be reduced.

[0008] (2) In some embodiments, in the configuration of (1) above, the counting unit resets the number of times when the charging execution determining unit determines that connection is possible.

[0009] According to the configuration (2) above, the counting unit resets the number of times that the charging execution determination unit has determined that connection is not possible when it determines that connection is possible, so that the start timing of charging (regular auxiliary charging) is a predetermined timing, and overcharging of the auxiliary battery can be prevented.

[0010] (3) In some embodiments, in the configuration of (1) above, the auxiliary equipment charge management unit includes a charging period extension unit that extends the charging period when the charging execution determination unit determines that connection is not possible.

[0011] According to the configuration (3) above, when the charging execution determination unit determines that connection is not possible, the charging period extension unit extends the charging period. This extends the charging time for the next charge (regular auxiliary charging), which reduces the frequency of the electric vehicle being unable to start due to a shortage of stored power in the auxiliary battery. [Effects of the Invention]

[0012] According to at least one embodiment of the present invention, it is possible to reduce the frequency with which an electric vehicle cannot be started due to a shortage of stored power in an auxiliary battery. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a block diagram illustrating a schematic configuration of a power supply management device for an electrically powered vehicle according to a first embodiment. [Figure 2] 2 is a diagram for explaining the period until scheduled auxiliary charging changed by the timing change unit shown in FIG. 1. FIG. [Figure 3] 4 is a flowchart showing an outline of the operation of the power supply management device for the electrically powered vehicle according to the first embodiment. [Figure 4] FIG. 10 is a block diagram illustrating a schematic configuration of a power supply management device for an electrically powered vehicle according to a second embodiment. [Figure 5] 5 is a diagram for explaining a charging period extended by the charging period extension unit shown in FIG. 4. FIG. [Figure 6] 10 is a flowchart illustrating an outline of the operation of a power supply management device for an electrically powered vehicle according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, several embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of components described as embodiments or shown in the drawings are merely illustrative examples and are not intended to limit the scope of the present invention.

[0015] [Embodiment 1] [Power Management Device Configuration] FIG. 1 is a block diagram showing a schematic configuration of a power supply management device 1A for an electrically powered vehicle according to the first embodiment.

[0016] The power supply management device 1A for an electrically powered vehicle according to the first embodiment is employed in electrically powered vehicles such as electric vehicles, hybrid vehicles, plug-in hybrid vehicles, etc. Plug-in hybrid vehicles are externally chargeable and capable of receiving external power supply.

[0017] As shown in FIG. 1, the electric vehicle is equipped with a contactor 7 that electrically connects or disconnects the drive battery 3 and the auxiliary battery 5. A DC-DC converter 9 is provided between the contactor 7 and the auxiliary battery 5. The DC-DC converter 9 converts the voltage of the drive battery 3 into a voltage that can be supplied to the auxiliary battery 5, and is activated when the drive battery 3 and the auxiliary battery 5 are electrically connected by the contactor 7, and is stopped when the drive battery 3 and the auxiliary battery 5 are electrically disconnected by the contactor 7.

[0018] The power supply management device 1A for an electric vehicle includes an auxiliary equipment charging management unit 11 and a connection management unit 13. The auxiliary equipment charging management unit 11 and the connection management unit 13 each include a processor (not shown) including an arithmetic unit, a register for storing instructions and information, and peripheral circuits, memories (not shown) such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and an input interface (not shown). An auxiliary equipment battery 5 is connected to the auxiliary equipment charging management unit 11 and the connection management unit 13, and power is constantly supplied from the auxiliary equipment battery 5 to the auxiliary equipment charging management unit 11 and the connection management unit 13.

[0019] The auxiliary equipment charge management unit 11 is provided with a request determination unit 15 that outputs a connection request for the contactor 7 for a predetermined charging period at a predetermined timing. The predetermined timing is the timing to start periodic auxiliary charging, and the predetermined charging period is the charging period of periodic auxiliary charging.

[0020] For example, the auxiliary charging management unit 11 is provided with a start date and time determination unit 17 that determines when to start periodic auxiliary charging, and a remaining period measurement unit 19 that measures the period (remaining period) until the periodic auxiliary charging ends, and the request determination unit 15 is configured to output a connection request for the contactor 7 when the time to start periodic auxiliary charging determined by the start date and time determination unit 17 arrives, as long as the remaining period measured by the remaining period measurement unit 19 remains. The time to start periodic auxiliary charging is, for example, the date and time when a predetermined period has elapsed since the end of the previous auxiliary charging (not limited to periodic auxiliary charging). For example, the start date and time determination unit 17 is configured to output a periodic auxiliary charging start request when the current date and time managed by a clock information management unit 21 connected to the auxiliary charging management unit 11 reaches the time to start periodic auxiliary charging determined by the start date and time determination unit 17. Furthermore, for example, the remaining period measurement unit 19 is configured to start measuring the remaining period when a periodic auxiliary charging start request is input, to end measurement of the remaining period when periodic auxiliary charging ends, and to output a periodic auxiliary charging request as long as there is remaining time. Furthermore, for example, the request determination unit 15 is configured to output a connection request for the contactor 7 only during the period when the periodic auxiliary charging request is input.

[0021] The connection management unit 13 is provided with a charging execution determination unit 23 that determines whether or not the contactor 7 can be connected when a connection request for the contactor 7 is input, and a counting unit 25 that counts the number of times the charging execution determination unit 23 determines that connection is not possible.

[0022] For example, the charging execution determination unit 23 is connected to a status management unit 29 having an information acquisition unit 27 that acquires opening / closing information of opening / closing members such as an engine hood, a tailgate, and a rear door, and the charging execution determination unit 23 is configured to determine that connection is possible when all of these opening / closing members are closed, and to determine that connection is not possible when at least one of these opening / closing members is open.

[0023] In addition, the charging execution determination unit 23 is configured to output a connection request to the contactor 7 only for the period during which the connection request to the contactor 7 is output from the request determination unit 15 when it determines that connection is possible, and to immediately output a disconnection request to the contactor 7 when it determines that connection is not possible.

[0024] The counting unit 25 resets the number of times when the charging execution determination unit 23 determines that connection is possible, but this is not limited to this, and for example, the counting unit 25 may be reset when the number of times that connection is determined to be possible reaches a predetermined number.

[0025] The auxiliary equipment charge management unit 11 is provided with a timing change section 31 that shortens the period until the start of regular auxiliary equipment charging as the number of times counted by the count section 25 increases.

[0026] 2, if the start timing of periodic auxiliary charging is set to a TA period (initial value) after the end of the previous auxiliary charging and the charging execution determination unit 23 determines that connection is not possible and the periodic auxiliary charging fails, the timing change unit 31 sets the start timing of the next periodic auxiliary charging to a TB period, which is shorter than the TA period. If the periodic auxiliary charging after the TB period fails, the timing change unit 31 sets the start timing of the next periodic auxiliary charging to a TC period, which is shorter than the TB period.

[0027] Also, for example, if the start timing of regular auxiliary charging is set to a period shorter than the TA period, when the charging execution determination unit 23 determines that connection is possible, the counting unit 25 resets the number of times, and the timing change unit 31 sets the start timing of the next regular auxiliary charging to the TA period (initial value).

[0028] [Power management device 1A operation] FIG. 3 is a flowchart showing an outline of the operation of the power supply management device 1A for an electrically powered vehicle according to the first embodiment.

[0029] As shown in FIG. 3, in the power supply management device 1A of the electrically powered vehicle according to the first embodiment, when it is time to start periodic auxiliary charging (step S11: Yes), the request determination unit 15 outputs a connection request for the contactor 7 for a predetermined time (step S13). When this connection request for the contactor 7 is input to the charging execution determination unit 23, the charging execution determination unit 23 determines whether the contactor 7 can be connected (step S15). If the charging execution determination unit 23 determines that the contactor 7 can be connected, the charging execution determination unit 23 outputs a connection request for the contactor 7 until the time during which the periodic auxiliary charging request is output from the remaining period measurement unit 19 ends (steps S17 to S21). As a result, the contactor 7 electrically connects the drive battery 3 and the auxiliary battery 5 at a predetermined timing until the predetermined time ends. As a result, power is supplied from the drive battery 3 to the auxiliary battery 5, and the auxiliary battery 5 is charged (periodic auxiliary charging).

[0030] On the other hand, if the charging execution determination unit 23 determines that the drive battery 3 and the auxiliary battery 5 are not electrically connected (step S19: No), the charging execution determination unit 23 outputs a request to disconnect the contactor 7 (step S23). This causes the contactor 7 to immediately electrically disconnect the drive battery 3 and the auxiliary battery 5. As a result, the power supply from the drive battery 3 to the auxiliary battery is cut off, and charging of the auxiliary battery 5 is stopped.

[0031] On the other hand, if the charging execution determination unit 23 determines that connection is not possible even when a connection request for the contactor 7 is input (step S15: No), the counting unit 25 counts the number of times that connection is not possible (step S25). When the counting unit 25 counts the number of times that connection is not possible, the timing changing unit 31 sets the timing to start the next periodic auxiliary charging to the TB period, which is shorter than the TA period (step S27). Then, if periodic auxiliary charging after the TB period fails, the timing changing unit 31 sets the timing to start the next periodic auxiliary charging to the TC period, which is shorter than the TB period (step S27).

[0032] When the start timing of periodic auxiliary charging is set to a period shorter than the TA period, and the charging execution determination unit 23 determines that connection is possible (step S15: Yes), the counting unit 25 resets the counted number (step S29). As a result, the timing changing unit 31 sets the start timing of the next periodic auxiliary charging to the TA period (initial value).

[0033] [effect] According to the power supply management device 1A for an electric vehicle of embodiment 1, the period until the predetermined timing is shortened as the number of times counted by the counting unit 25 increases, so that the timing to start charging (regular auxiliary charging) is advanced, and the frequency of the electric vehicle being unable to stay on track due to a shortage of stored power in the auxiliary battery 5 can be reduced.

[0034] In addition, the counting unit 25 resets the number of times that the charging execution determination unit 23 has determined that connection is not possible when it determines that connection is possible, so that the start timing of charging (periodic auxiliary charging) is a predetermined timing, thereby preventing overcharging of the auxiliary battery 5.

[0035] [Embodiment 2] [Power Management Device Configuration] FIG. 4 is a block diagram showing a schematic configuration of a power supply management device 1B for an electrically powered vehicle according to the second embodiment.

[0036] The configurations of the request determination unit 15 of the auxiliary charging management unit 11 and the charging execution determination unit 23 of the connection management unit 13 of the power supply management device 1B of the electric vehicle of embodiment 2 are the same as the configurations of the request determination unit 15 of the connection management unit 13 and the charging execution determination unit 23 of the connection management unit 13 of the power supply management device 1A of the electric vehicle of embodiment 1.

[0037] As shown in FIG. 4, the auxiliary equipment charge management unit 11 includes a charging period extension unit 33 that extends the charging period when the charging execution determination unit 23 determines that connection is not possible.

[0038] For example, as shown in FIG. 5, when the charging period is set to the TX period (initial value), if the charging execution determination unit 23 determines that connection is not possible and the regular auxiliary charging fails, the charging period extension unit 33 sets the charging period of the next regular auxiliary charging to the TY period, which is longer than the TX period.

[0039] Also, for example, when the charging period for regular auxiliary charging is set to TY, which is longer than the TX period, if the charging execution determination unit 23 determines that connection is possible, the charging period extension unit 33 sets the charging period for the next regular auxiliary charging to the TX period (initial value).

[0040] [Power management device 1B operation] FIG. 6 is a flowchart showing an outline of the operation of the power supply management device 1B for an electrically powered vehicle according to the second embodiment.

[0041] The operation of the request determination unit 15 of the auxiliary charging management unit 11 and the charging execution determination unit 23 of the connection management unit 13 of the power supply management device 1B of the electric vehicle of embodiment 2 is the same as the operation of the request determination unit 15 of the auxiliary charging management unit 11 and the charging execution determination unit 23 of the connection management unit 13 of the power supply management device 1A of the electric vehicle of embodiment 1.

[0042] As shown in FIG. 6, in the power supply management device 1B of the electrically powered vehicle according to the second embodiment, when a connection request for the contactor 7 is input to the charging execution determination unit 23 but the charging execution determination unit 23 determines that connection is not possible (step S15: No), the charging period extension unit 33 sets the charging time for the periodic auxiliary charging to a TY period that is longer than the TX period (step S31).

[0043] When the charging period for regular auxiliary charging is set to a period shorter than period a, if the charging execution determination unit 23 determines that connection is possible (step S15: Yes), the charging period extension unit 33 sets the charging period for regular auxiliary charging to the TX period (initial value) (step S33).

[0044] [effect] According to the power supply management device 1B for an electric vehicle of embodiment 2, when the charging execution determination unit 23 determines that connection is not possible, the charging period extension unit 33 extends the charging period, thereby extending the charging time for the next charge (regular auxiliary charging), resulting in a shortage of stored power in the auxiliary battery 5, and reducing the frequency of the electric vehicle being unable to start. [Explanation of symbols]

[0045] 1A,1B Power management device 3 Drive battery 5 Auxiliary battery 7 Contactor 9 DC-DC converter 11 Auxiliary charging management unit 13 Connection Management Unit 15 Request determination section 17 Start date and time determination section 19 Remaining period measurement unit 21 Clock Information Management Unit 23 Charging execution determination unit 25 Counting section 27 Information Acquisition Department 29 State Management Unit 31 Timing change section 33 Charging period extension part

Claims

1. A power supply management device for an electric vehicle equipped with a contactor that electrically connects or disconnects a drive battery and an auxiliary battery, an auxiliary equipment charge management unit including a request determination unit that outputs a connection request for the contactor for a predetermined charging period at a predetermined timing; a connection management unit including: a charging execution determination unit that determines whether or not the contactor can be connected based on open / close information of an open / close member of the electric vehicle when a connection request for the contactor is input; and a counting unit that counts the number of times the charging execution determination unit determines that the contactor cannot be connected; Equipped with The auxiliary equipment charge management unit includes a timing change unit that shortens the period until the predetermined timing as the number of times counted by the count unit increases. Power management device for electric vehicles.

2. the counting unit resets the number of times when the charging execution determination unit determines that connection is possible. The power supply management device for an electric vehicle according to claim 1 .

3. the auxiliary equipment charge management unit includes a charging period extension unit that extends the charging period when the charging execution determination unit determines that connection is not possible. The power supply management device for an electric vehicle according to claim 1 or 2.

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