JP6927005B2 - Power supply - Google Patents

Description

The present disclosure relates to the control of a power supply unit having a plurality of assembled batteries.

Conventionally, in a power supply device including a plurality of assembled batteries, the plurality of assembled batteries may be connected by a connecting member such as a bus bar. In such a power supply device, the voltage of each assembled battery is monitored by using a voltage detection device. For example, Japanese Patent Application Laid-Open No. 2011-253721 (Patent Document 1) discloses a voltage monitoring device that monitors the voltage of each group divided into two or more in a plurality of fuel cells.

Japanese Unexamined Patent Publication No. 2011-253721

When a plurality of assembled batteries are connected by using a connecting member as described above, the connecting member may be fastened to the terminal of each assembled battery by using, for example, a bolt or the like. In such a case, if the bolts and the like are loosened, the conduction resistance in the connecting member may increase. As a result, the temperature of the connecting member may rise due to the rise in conduction resistance. In the above-mentioned Patent Document 1, no consideration is given to such a problem.

The present disclosure has been made to solve the above-mentioned problems, and an object of the present disclosure is to provide a power supply device for suppressing a temperature rise of a connecting member connecting a plurality of assembled batteries.

The power supply device according to a certain aspect of the present disclosure includes a battery including a first set battery, a second set battery, and a connecting member for connecting the first set battery and the second set battery in series, and one end of the connecting member. A first detection device that detects the voltage between the ends of the unit and the other end, a second detection device that detects the current flowing through the battery, and a power control device that controls the power input and output from the battery. Be prepared. The power control device calculates the power consumption of the connecting member using the voltage between the ends and the current, and when the calculated power consumption is larger than the allowable power amount, the current is before the calculation of the power consumption amount. Control the power input and output in the battery so that it is lower than the current.

In this way, the power consumption of the connecting member can be made lower than the allowable power amount. Thereby, the temperature rise of the connecting member can be suppressed.

According to the present disclosure, it is possible to provide a power supply device that suppresses a temperature rise of a bus bar that connects a plurality of assembled batteries.

It is a figure which shows the whole structure of the power supply device which concerns on this embodiment. It is a figure for demonstrating an example of the structure which connects between a plurality of assembled batteries. It is a flowchart for demonstrating the control process executed by a control device. It is a flowchart for demonstrating the control process executed by the control apparatus in a modification.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals, and the description thereof will not be repeated.

FIG. 1 shows the configuration of the power supply device 1 according to the present embodiment. The power supply device 1 according to the present embodiment includes a control device 10, a battery 20, a voltage measuring unit 30, a temperature sensor 40, and a current sensor 50.

In the present embodiment, the battery 20 is, for example, a battery mounted on a vehicle or the like. The battery 20 supplies power to a load (not shown). The load includes, for example, a power converter such as an inverter or a converter, and a motor generator that can be a power source for the vehicle.

The battery 20 includes a plurality of assembled batteries. In the present embodiment, the battery 20 includes a first set battery 22, a bus bar 24, and a second set battery 26. The number of assembled batteries included in the battery 20 is not particularly limited to two. The assembled battery may be composed of the same number of battery cells, or may be composed of a different number of battery cells.

The first set battery 22 includes a plurality of battery cells. In the present embodiment, the first set battery 22 has a configuration in which a predetermined number of battery blocks 22b in which a predetermined number (for example, three in the present embodiment) of battery cells are connected in parallel are connected in series. ..

The second set battery 26 includes a plurality of battery cells. In the present embodiment, the second set battery 26 has a configuration in which a predetermined number of battery blocks 26b in which a predetermined number (for example, three in the present embodiment) of battery cells are connected in parallel are connected in series. ..

The first set battery 22 and the second set battery 26 are connected in series by the bus bar 24. The bus bar 24 is energized so as to be able to connect, for example, the electrode terminal (for example, the negative electrode terminal) of the first set battery 22 and the electrode terminal (for example, the positive electrode terminal) of the opposite polarity of the second set battery 26. It is a possible connecting member. The bus bar 24 may be configured to connect the positive electrode terminal of the first set battery 22 and the negative electrode terminal of the second set battery 26.

FIG. 2 is a diagram for explaining an example of a configuration in which a plurality of assembled batteries are connected. As shown in FIG. 2, the first set battery 22 includes a predetermined number of battery blocks 22b, a plurality of inter-block bus bars 22c, and a terminal bus bar 22d.

The battery block 22b includes a plurality of battery cells 22a. In the present embodiment, the battery block 22b is configured by arranging three square battery cells 22a in a row. In the battery block 22b, the battery cell 22a has a surface on which the positive electrode terminal and the negative electrode terminal are provided as the upper surface, and the rectangular side of the upper surface in the longitudinal direction is the longitudinal side of the upper surface of the adjacent battery cell 22a in the rectangular shape. They are arranged so that they face each other.

The battery block 22b is connected in series with the adjacent battery block 22b by an inter-block bus bar 22c. Specifically, the inter-block bus bar 22c is connected to each of the electrode terminals (for example, positive electrode terminals) having the same polarity in the three battery cells 22a included in the battery block 22b. Further, the inter-block bus bar 22c is an electrode terminal having the same polarity in the three battery cells 22a included in the adjacent battery block 22b, and has an electrode terminal having a polarity different from that of the connected battery block 22b. For example, it is connected to each of the negative electrode terminals). In this way, the inter-block bus bar 22c connects the three battery cells 22a in parallel in the battery block 22b and connects them in series with the adjacent battery blocks 22b. The inter-block bus bar 22c and the battery cell 22a are connected by fastening with bolts, nuts, or the like, for example.

In the three battery cells 22a included in the battery block 22b arranged at the end of the plurality of battery blocks 22b, the inter-block bus bar 22c is connected to each of one of the electrode terminals. A terminal bus bar 22d is connected to each of the electrode terminals at the other end. Each of the electrode terminals of the three battery cells 22a is connected to one end side of the terminal bus bar 22d, and one end of the bus bar 24 is connected to the other end of the terminal bus bar 22d. The terminal bus bar 22d and the battery cell 22a are connected by fastening with bolts, nuts, or the like, for example. The terminal bus bar 22d and the bus bar 24 are connected by fastening with bolts, nuts, or the like, for example.

The second set battery 26 includes a predetermined number of battery blocks 26b, a plurality of inter-block bus bars 26c, and a terminal bus bar 26d. Further, the battery block 26b includes a plurality of battery cells 26a. The configuration of the second set battery 26 is the same as the configuration of the first set battery 22. Therefore, the detailed explanation will not be repeated.

Each of the electrode terminals of the three battery cells 26a is connected to one end side of the terminal bus bar 26d, and the other end of the bus bar 24 is connected to the other end of the terminal bus bar 26d. The terminal bus bar 22d and the bus bar 24 are connected by fastening using, for example, bolts or nuts.

Returning to FIG. 1, the voltage measuring unit 30 detects the voltage and the like of each of the plurality of battery blocks 22b and 26b of the battery 20. The positive electrode terminal of the first set battery 22, between the adjacent battery blocks 22b, the negative electrode terminal of the first set battery 22, the positive terminal of the second set battery 26, between the adjacent battery blocks 26b, and the second set battery 26. One end of each of the plurality of wires is connected to the negative electrode terminal of the above. The other end of each of the plurality of wires is connected to an input unit (not shown) of the voltage measuring unit 30.

The voltage measuring unit 30 detects the respective voltages of the plurality of battery blocks 22b and 26b and the voltage between the ends of the bus bar 24 (hereinafter, referred to as the voltage between the ends) Vbb using these plurality of wirings. do. The voltage measuring unit 30 transmits the detected voltages of the plurality of battery blocks 22b and 26b and the voltage between the ends Vbb to the control device 10.

The temperature sensor 40 detects the temperature TB of the battery 20. The temperature sensor 40 transmits a signal indicating the detected temperature TB of the battery 20 to the control device 10. The temperature sensor 40 may detect, for example, the temperature around the battery 20 as the temperature TB.

The current sensor 50 detects the current Ib flowing through the battery 20. The current sensor 50 transmits a signal indicating the detected current Ib to the control device 10.

The control device 10 includes a calculation unit 12 and a storage unit 14. The calculation unit 12 includes, for example, a CPU (Central Processing Unit) configured to be able to execute a predetermined calculation process based on information such as a program stored in the storage unit 14.

The storage unit 14 includes various types of memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory), for example.

The control device 10 receives various signals from the voltage measuring unit 30, the temperature sensor 40, and the current sensor 50, and controls the power input / output to / from the battery 20 based on the received various signals. The control device 10 controls the power input / output to / from the battery 20 by controlling the power conversion device described above, for example.

In the power supply device 1 having the above configuration, if the connection state between the bus bar 24 and the terminal bus bar 22d or the connection state between the bus bar 24 and the terminal bus bar 26d becomes loose, the conduction resistance in the bus bar 24 increases. There is. As a result, the temperature of the bus bar 24 may rise. In particular, since the energizing current is large in a high-voltage battery, the temperature rise may be large.

Therefore, in the present embodiment, the control device 10 calculates the power consumption of the bus bar 24 using the end-to-end voltage Vbb and the current Ib, and the calculated power consumption is larger than the allowable power consumption. In addition, the power input / output in the battery 20 is controlled so that the current is lower than the current before the calculation of the power consumption.

In this way, the power consumption of the bus bar can be made lower than the allowable power amount. Thereby, the temperature rise of the bus bar can be suppressed.

Hereinafter, the control process executed by the control device 10 of the power supply device 1 according to the present embodiment will be described with reference to FIG. FIG. 3 is a flowchart for explaining the control process executed by the control device 10. The control device 10 executes, for example, the process shown in FIG. 3 every time the set time elapses.

At step 100 (hereinafter, step is referred to as S) 100, the control device 10 resets the elapsed time t to the initial value (zero).

In S102, the control device 10 calculates the elapsed time. Specifically, the control device 10 calculates the value obtained by adding the predetermined time Δt to the previous value of the elapsed time t as the current value of the elapsed time t.

In S104, the control device 10 acquires the end-to-end voltage Vbb (n). The control device 10 acquires the voltage between ends Vbb (n) from the voltage measuring unit 30.

In S106, the control device 10 acquires the current Ib (n). The control device 10 acquires the current Ib (n) from the current sensor 50.

In S108, the control device 10 calculates the power consumption ΔEbb (n) at the predetermined time Δt by multiplying the end-to-end voltage Vbb (n), the current Ib (n), and the predetermined time Δt.

In S110, the control device 10 calculates the current value ΔEbb (n) of the power consumption by adding the power consumption ΔEbb (n) at the predetermined time Δt to the previous value Ebb (n-1) of the power consumption. do.

In S112, the control device 10 determines whether or not the elapsed time t exceeds the set time. When the elapsed time t exceeds the set time (YES in S112), the process is transferred to S114. If the elapsed time t does not exceed the set time (NO in S112), the process is returned to S102.

At S114, the control device 10 acquires the temperature TB. The control device 10 acquires the temperature TB from the temperature sensor 40.

In S116, the control device 10 sets the allowable electric energy A based on the temperature TB from the storage unit 14. In the storage unit 14, for example, a map or a mathematical formula showing the relationship between the temperature TB and the allowable electric energy A is stored. The map or mathematical formula is set so that, for example, the higher the temperature TB, the lower the allowable electric energy A, and the lower the temperature TB, the higher the allowable electric energy A. The relationship between the temperature TB and the allowable electric energy A is adapted and set by, for example, an experiment or the like. The relationship between the temperature TB and the allowable electric energy A may be a linear relationship or a non-linear relationship.

In S118, the control device 10 determines whether or not the current value Ebb (n) of the power consumption amount is larger than the allowable power amount A. When it is determined that the current value Ebb (n) of the power consumption amount is larger than the allowable power amount A (YES in S118), the processing is transferred to S120. When it is determined that the current value Ebb (n) of the power consumption amount is equal to or less than the allowable power amount A (NO in S118), this process is terminated.

In S120, the control device 10 executes current suppression control. Specifically, for example, when the battery 20 is discharged, the control device 10 lowers the output voltage from the power conversion device to the power supply destination to be lower than before the calculation of the power consumption, so that the current flowing through the battery 20 flows. To reduce. Alternatively, for example, when charging the battery 20, the control device 10 reduces the current flowing through the battery 20 by lowering the voltage supplied from the power converter to the battery 20 than before calculating the power consumption. It may be.

The operation of the power supply device 1 based on the above structure and the flowchart will be described. For example, assume that power is being supplied to the load from the battery 20.

When the elapsed time t is reset to the initial value (S100), the calculation of the elapsed time is started (S102). At this time, when the inter-end voltage Vbb is acquired (S104) and the current Ib is acquired (S106), the acquired inter-end voltage Vbb, the current Ib, and the predetermined time Δt are multiplied by each other. , The power consumption ΔEbb (n) at a predetermined time Δt is calculated (S108).

The current value Ebb (n) of the power consumption is calculated by adding the power consumption ΔEbb (n) at the predetermined time Δt to the previous value Ebb (n-1) of the power consumption (S110).

When the elapsed time t is equal to or less than the set time (NO in S112), the above calculation (S102 to S110) is repeated, so that the calculated power consumption increases as the time elapses.

When the elapsed time t exceeds the set time (YES in S112), the temperature TB is acquired (S114), and the allowable electric energy A is set based on the acquired temperature TB (S116).

When the power consumption Ebb (n) in the set time is larger than the allowable electric energy A (YES in S118), the current suppression control is executed (S120). By executing the current suppression control, the current Ib flowing through the battery 20 is lower than that before the calculation of the power consumption. As a result, the temperature rise of the bus bar 24 is suppressed.

As described above, according to the power supply device 1 according to the present embodiment, the power consumption amount Ebb (n) in the bus bar 24 can be made lower than the allowable power amount A. Thereby, the temperature rise of the bus bar 24 can be suppressed. Therefore, it is possible to provide a power supply device that suppresses a temperature rise of a bus bar that connects a plurality of assembled batteries.

Further, for example, when compared with the configuration in which the temperature rise of the bus bar 24 is detected by using a temperature sensor or the like, if the bus bar 24 has a plurality of fastening points, it is necessary to provide a temperature sensor at each fastening point. On the other hand, the power supply device 1 according to the present embodiment only needs to have a configuration capable of detecting the voltage Vbb between the ends, and can suppress the increase in cost when detecting the temperature rise of the bus bar 24. can.

Hereinafter, modification examples will be described.
In the above-described embodiment, the bus bar has been described as an example as a connecting member for connecting the assembled batteries in series, but a cable may be used, for example.

Further, in the above-described embodiment, the first set battery 22 and the second set battery 26 are each configured by connecting a predetermined number of battery blocks 22b and 26b in which three battery cells are connected in parallel in series. However, for example, at least one of the first set battery 22 and the second set battery 26 may be configured by connecting a predetermined number of battery cells in series.

Further, in the above-described embodiment, the case where the first set battery 22 and the second set battery 26 both have a configuration in which a plurality of battery cells are arranged in one row has been described as an example, but the first set battery 22 and the second set battery 26 are arranged in a plurality of rows. May have such a configuration.

Further, in the above-described embodiment, the current suppression control is executed when the power consumption Ebb (n) in the bus bar 24 is larger than the allowable electric energy A set based on the temperature TB. The current suppression control may be executed when the power consumption of the bus bar 24 is larger than the allowable power B set based on the temperature TB.

Hereinafter, the control process executed by the control device 10 in this modification will be described with reference to FIG. FIG. 4 is a flowchart showing a control process executed by the control device 10 in the modified example. The control device 10 executes, for example, the control process shown in FIG. 4 every time a predetermined time elapses.

At S200, the control device 10 acquires the end-to-end voltage Vbb. At S202, the control device 10 acquires the current Ib. At S204, the control device 10 acquires the temperature TB.

In S206, the control device 10 calculates the power consumption Pbb. Specifically, the control device 10 calculates the power consumption Pbb in the bus bar 24 by multiplying the end-to-end voltage Vbb and the current Ib.

In S208, the control device 10 sets the allowable power B based on the temperature TB from the storage unit 14. In the storage unit 14, for example, a map or a mathematical formula showing the relationship between the temperature TB and the allowable power B is stored. The map or formula is set so that, for example, the higher the temperature TB, the lower the permissible power, and the lower the temperature TB, the higher the permissible power B. The relationship between the temperature TB and the allowable power B is adapted and set by, for example, an experiment or the like. The relationship between the temperature TB and the allowable power B may be a linear relationship or a non-linear relationship.

In S210, the control device 10 determines whether or not the power consumption Pbb is larger than the allowable power B. When it is determined that the power consumption Pbb is larger than the allowable power B (YES in S210), the process is transferred to S212. When it is determined that the power consumption Pbb is equal to or less than the allowable power B (NO in S210), this process is terminated. At S212, the control device 10 executes current suppression control.

The operation of the control device 10 in the modified example will be described below. For example, assume that power is being supplied to the load from the battery 20.

At this time, the end-to-end voltage Vbb is acquired (S200), the current Ib is acquired (S202), and the temperature TB is acquired (S204). By multiplying the acquired end-to-end voltage Vbb and the current Ib, the power consumption Pbb is calculated (S206), and the allowable power B is set based on the acquired temperature TB (S208).

When the power consumption of the bus bar 24 is larger than the allowable power B (YES in S210), the current suppression control is executed, so that the current Ib flowing through the battery 20 is lower than that before the calculation of the power consumption. As a result, the temperature rise of the bus bar 24 is suppressed.

Even in this way, the power consumption Pbb of the bus bar 24 can be made lower than the allowable power B, so that the temperature rise of the bus bar 24 can be suppressed.

In addition, the above-mentioned modification may be carried out by appropriately combining all or a part thereof.
It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present disclosure is indicated by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 power supply, 10 controller, 12 arithmetic unit, 14 storage unit, 20 battery, 22 first set battery, 22a, 26a battery cell, 22b, 26b battery block, 22c, 26c block-to-block bus bar, 22d, 26d terminal bus bar, 24 busbar, 26 second set battery, 30 voltage measuring unit, 40 temperature sensor, 50 current sensor.

Claims (1)

A battery including a first set battery, a second set battery, and a connecting member for connecting the first set battery and the second set battery in series.
A first detection device that detects an end-to-end voltage between one end and the other end of the connecting member,
A second detection device that detects the current flowing through the battery, and
A power control device for controlling the power input / output in the battery is provided.
The power control device calculates the power consumption of the connecting member using the voltage between the ends and the current, and when the calculated power consumption is larger than the allowable power amount, the current is said to be the current. A power supply device that controls the power input and output in the battery so that the current is lower than the current before the calculation of the electric energy consumption.

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