Power supply system

Abstract

To suppress a short circuit that may occur inside a power supply system during water immersion, as much as possible.SOLUTION: The present power supply system includes: a battery unit group in which a plurality of battery units are arranged while polarities in a vertical direction are aligned, each battery unit including a plurality of battery modules stacked electrically in series; a connecting wire that connects the plurality of battery units in series; and a cut-off section that is provided at a higher position than the battery unit group in the connecting wire and that cuts off the connecting wire if water immersion is detected.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a power supply system.

Background Art

[0002] A power supply system equipped with a storage battery is in use. When water intrusion occurs in such a power supply system, abnormalities such as electric leakage may occur. Therefore, a power supply system has been proposed that suppresses abnormalities such as electric leakage by discharging the power stored in the storage battery or stopping charge and discharge when water intrusion occurs (see, for example, Patent Documents 1-4).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the countermeasures against water intrusion described in each of the above patent documents, it was difficult to cut off the short-circuit path that occurs inside the power supply system due to water intrusion. Therefore, there is room for improvement in the countermeasures against water intrusion of the power supply system.

[0005] One aspect of the disclosed technology aims to provide a power supply system that can suppress as much as possible a short circuit that may occur inside the power supply system during water intrusion.

Means for Solving the Problems

[0006] One aspect of the disclosed technology is exemplified by the following power supply system: This power supply system comprises a group of battery units, each consisting of multiple battery modules electrically stacked in series, arranged in a manner that aligns the polarity in the vertical direction; a connecting line connecting the multiple battery units in series; and a shut-off unit located at a higher position than the group of battery units on the connecting line, which shuts off the connecting line when water ingress is detected.

[0007] In the above power supply system, the interruption section is located higher than the battery units in the connecting wires, making the interruption section less susceptible to water ingress. Furthermore, because the connecting wires that connect the multiple battery units in series are interrupted by the interruption section, short circuits that may occur within the power supply system are suppressed as much as possible.

[0008] Here, the interruption unit may include a circuit breaker, which shuts off the connecting wire by turning off the circuit breaker when the water ingress is detected. Alternatively, the interruption unit may include a relay, which shuts off the connecting wire by controlling the relay when the water ingress is detected.

[0009] The above power supply system may also have the following features: It further includes a log collection unit that receives power from the battery unit group and records the operation of the battery unit group and the interruption unit. The interruption unit includes a first relay, a second relay and a resistor arranged in parallel with the first relay. When the water ingress is detected, the interruption unit controls the first relay to interrupt the current flowing through the connection line. The current is suppressed, and once a predetermined time has elapsed until the log collection unit has finished collecting logs, the second relay is controlled to interrupt the current passing through the second relay, thereby interrupting the connection line. When the current passing through the first relay is interrupted, the current flowing between the multiple battery units passes through the resistor, thus suppressing the current flowing through the connection line. As a result, adverse effects due to short circuits are suppressed. Furthermore, since power can be supplied to the log collection unit while suppressing adverse effects due to short circuits, the effects of water ingress can be recorded. In addition, the power supply system also interrupts the current passing through the second relay once the predetermined time has elapsed, interrupting the connection line and suppressing short circuits. [Effects of the Invention]

[0010] This power supply system can minimize the risk of short circuits occurring within the power supply system during flooding. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 shows an example of a power supply system according to an embodiment. [Figure 2] Figure 2 shows an example of a power supply system related to a comparative example. [Figure 3] Figure 3 schematically shows what happens when water ingress occurs in the power supply system of the comparative example. [Figure 4] Figure 4 is a schematic diagram showing what happens when water ingress occurs in the power supply system according to this embodiment. [Figure 5] Figure 5 shows an example of a power supply system according to the first modified example. [Figure 6] Figure 6 shows an example of a power supply system according to the second modified example. [Figure 7] Figure 7 shows an example of the processing flow of a power supply system according to the second modified example. [Modes for carrying out the invention]

[0012] <Embodiment> The embodiments will be further described below with reference to the drawings. Figure 1 is a diagram showing an example of a power supply system 1 according to an embodiment. The power supply system 1 includes a positive electrode wire 2, an inter-unit connection wire 3, a negative electrode wire 4, a relay 5, a circuit breaker 6, a fuse 7, a positive electrode output terminal 8, a negative electrode output terminal 9, a first battery unit 10a, a second battery unit 10b, and a control unit 100. When the first battery unit 10a and the second battery unit 10b are not distinguished, they are also referred to as battery unit 10.

[0013] Power supply system 1 supplies power from the first battery unit 10a and the second battery unit 10b, which are connected in series, to the load via the positive output terminal 8 and the negative output terminal 9. The positive terminal 12a of the first battery unit 10a is connected to the positive output terminal 8 by the positive wire 2. The negative terminal 13b of the second battery unit 10b is connected to the negative output terminal 9 by the negative wire 4. The negative terminal 13a of the first battery unit 10a and the positive terminal 12b of the second battery unit 10b are connected by an inter-unit connection wire 3. The inter-unit connection wire 3 is an example of a "connection wire". The first battery unit 10a and the second battery unit 10b are examples of "battery units". The first battery unit 10a and the second battery unit 10b are an example of a "group of battery units".

[0014] The first battery unit 10a is a unit in which battery modules 11a, 11b, 11c, and 11d are arranged in a row and connected in series. The second battery unit 10b is a unit in which battery modules 11e, 11f, 11g, and 11h are arranged in a row and connected in series. Each of the battery modules 11a, 11b, 11c, 11d, 11e, 11f, 11g, and 11h is, for example, a single secondary battery. Each of the battery modules 11a, 11b, 11c, 11d, 11e, 11f, 11g, and 11h is, for example, multiple secondary batteries. The battery module may include a battery. Battery modules 11a, 11b, 11c, 11d, 11e, 11f, 11g, and 11h are examples of "battery modules".

[0015] In the power supply system 1, the first battery unit 10a and the second battery unit 10b are arranged with their polarities aligned. That is, both the first battery unit 10a and the second battery unit 10b are arranged with the same polarity facing down (or up). In the example of FIG. 1, both the first battery unit 10a and the second battery unit 10b are arranged with their negative electrodes (negative electrodes 13a, 13b) facing down. And the first battery unit 10a and the second battery unit 10b are arranged side by side, for example, at the same height. Therefore, the unit connection line 3 extends from below the first battery unit 10a toward above the second battery unit 10b.

[0016] Also, a breaker 6 is arranged between the positive electrode 12a and the positive electrode output terminal 8 in the positive electrode line 2, between the negative electrode 13a and the positive electrode 12b in the unit connection line 3, and between the negative electrode 13b and the negative electrode output terminal 9 in the negative electrode line 4. The breaker 6 is arranged at a position higher than the battery unit 10. By turning off (cutting off) the breaker 6, the current between the positive electrode 12a and the positive electrode output terminal 8 in the positive electrode line 2, between the negative electrode 13a and the positive electrode 12b in the unit connection line 3, and between the negative electrode 13b and the negative electrode output terminal 9 in the negative electrode line 4 is cut off. The breaker 6 is an example of a "cut-off portion".

[0017] A relay 5 is arranged between the positive electrode output terminal 8 and the breaker 6 in the positive electrode line 2. The relay 5 can switch between a state of cutting off the current in the unit connection line 3 and a state of allowing the current to flow. Also, a fuse 7 is arranged between the negative electrode output terminal 9 and the breaker 6 in the negative electrode line 4. Note that the fuse 7 may be provided in the positive electrode line 2 instead of the negative electrode line 4, or may be provided in both the positive electrode line 2 and the negative electrode line 4. The fuse 7 is cut off when a current outside the allowable range flows through the negative electrode line 4. And when the fuse 7 is cut off, the current flowing through the negative electrode line 4 is cut off.

[0018] The control unit 100 can be considered as a computer having an arithmetic unit, memory device, etc. The control unit 100 operates by receiving power from the battery unit 10. The control unit 100 executes a predetermined program, etc., to turn off the breaker 6 in response to the detection of water ingress in the first battery unit 10a and the second battery unit 10b. There are no limitations on the method of detecting water ingress, and various known methods can be adopted. For example, the control unit 100 turns off the breaker 6 by outputting a command signal to the breaker 6 via a signal line (not shown) to turn off the breaker 6.

[0019] Figure 2 shows an example of a power supply system 500 related to a comparative example. In power supply system 500, an inter-unit connection line 300 is used instead of the inter-unit connection line 3. The inter-unit connection line 300 differs from the inter-unit connection line 3 of power supply system 1 in that it is not connected to the breaker 6. In power supply system 500, when water ingress is detected, the breaker 6 is turned off by the control unit 400.

[0020] Figure 3 schematically shows the case where flooding occurs in the power supply system 500 according to the comparative example. In Figure 2, the flooded area R1 schematically shows the area that has been flooded. In Figure 2, the battery module 11d, which is the lowest battery module of the first battery unit 10a, and the battery module 11h, which is the lowest battery module of the second battery unit 10b, are submerged in water due to flooding.

[0021] When battery modules 11d and 11h are submerged in water, a short circuit is formed, for example, as illustrated by the short circuit path W1. Then, in the power supply system 500, Even if the -6 is turned off, the short-circuit path W1 cannot be interrupted. Therefore, the current flowing through the short-circuit path W1 may cause the water in the submerged area R1 to electrolyze and generate hydrogen, which could lead to a fire using the electrical equipment of the power supply system 500 as an ignition source.

[0022] Figure 4 schematically shows the case when flooding occurs in the power supply system 1 according to the embodiment. In Figure 4, the flooded area R2 schematically shows the flooded area. In the case of Figure 4, the battery module 11d, which is the lowest battery module of the first battery unit 10a, and the battery module 11h, which is the lowest battery module of the second battery unit 10b, are submerged in water due to flooding. If the inter-unit connection line 3 is not interrupted while the battery modules 11d and 11h are submerged, a short circuit path such as the one exemplified by the short circuit path W2 is formed.

[0023] In this embodiment, when flooding, as exemplified by the flooded area R1, is detected, the control unit 100 turns off the breaker 6. Turning off the breaker 6 interrupts the inter-unit connection line 3. As a result, the current between the negative electrode 13a and the positive electrode 12b in the inter-unit connection line 3 is interrupted. That is, the short-circuit path schematically shown by the short-circuit path W2 in Figure 4 is not formed, and the electrolysis of the flooded water is suppressed. Consequently, the occurrence of a fire in the power supply system 1 is suppressed.

[0024] <First variation> In the embodiment described above, the inter-unit connection line 3 is connected to the circuit breaker 6, and when flooded, the circuit breaker 6 is turned off, disconnecting the inter-unit connection line 3 and interrupting the short circuit path. In the first modified example, instead of connecting the inter-unit connection line 3 to the circuit breaker 6, a configuration in which a relay is placed on the inter-unit connection line 3 will be described. In the first modified example, components identical to those in the embodiment are denoted by the same reference numerals, and their descriptions are omitted.

[0025] Figure 5 shows an example of a power supply system 1a according to the first modified example. In the power supply system 1a, instead of connecting the inter-unit connection line 3 to the breaker 6, a relay 5a is placed on the inter-unit connection line 3. The relay 5a is placed at a higher position than the battery unit 10. When water ingress is detected, the control unit 100a turns off the breaker 6 by outputting a control signal via, for example, a signal line (not shown), and also controls the relay 5a to interrupt the current passing through the relay 5a.

[0026] In the first modified example, when water enters the system, the current passing through relay 5a is interrupted, thereby interrupting the current between the negative electrode 13a and the positive electrode 12b in the inter-unit connection line 3. As a result, for example, the short-circuit path schematically shown by the short-circuit path W2 in Figure 4 is not formed, and the electrolysis of the water that has entered the system is suppressed. Consequently, the occurrence of a fire in the power supply system 1a is suppressed. Furthermore, even if the breaker 6 or relay 5 does not operate normally due to reasons such as contact welding or failure, the added relay 5a can interrupt the current. Therefore, the safety redundancy of the power supply system 1a can be increased.

[0027] <Second variation> In the first modified example, relay 5a is placed on the inter-unit connection line 3. In the second modified example, a configuration in which a relay and a resistor are placed in parallel with relay 5a will be described. In the second modified example, the same reference numerals are used for components identical to those in the embodiment and the first modified example, and their descriptions are omitted.

[0028] Figure 6 shows an example of a power supply system 1b according to the second modified example. In power supply system 1b, relay 5b and resistor 20 are arranged in parallel with relay 5a in the inter-unit connection line 3. The resistance value of resistor 20 is determined as appropriate. Relay 5a is an example of the "first relay". Relay 5b is an example of the "second relay".

[0029] When water ingress is detected, the control unit 100b first controls relay 5a to interrupt the current passing through relay 5a. This interruption allows current to flow from the negative terminal 13a of the first battery unit 10a to the positive terminal 12b of the second battery unit 10b through relay 5b and resistor 20. The current flowing between the negative terminal 13a of the first battery unit 10a and the positive terminal 12b of the second battery unit 10b is suppressed by resistor 20. In other words, in this state, the current flowing through the short-circuit path schematically shown by the short-circuit path W2 in Figure 4 is suppressed.

[0030] The control unit 100b receives power from the first battery unit 10a and the second battery unit 10b while the current from the negative electrode 13a of the first battery unit 10a to the positive electrode 12b of the second battery unit 10b is suppressed, and performs log collection. The information recorded in the collected log may include, for example, the time when flooding is detected, the voltages of the first battery unit 10a and the second battery unit 10b when flooding is detected, the time when the current via relay 5a is interrupted, and the current value flowing between the negative electrode 13a of the first battery unit 10a and the positive electrode 12b of the second battery unit 10b when the current via relay 5a is interrupted. The control unit 100b is an example of a "log collection unit".

[0031] When a predetermined time has elapsed until log collection is complete, the control unit 100b cuts off the current via relay 5b, turns off breaker 6, and disconnects the inter-unit connection line 3. Disconnecting the inter-unit connection line 3 disconnects the short-circuit path schematically shown by the short-circuit path W2 in Figure 4.

[0032] Figure 7 shows an example of the processing flow of the power supply system 1b according to the second modified example. The following description of the example of the processing flow of the power supply system 1b will refer to Figure 7.

[0033] In S1, when the control unit 100b detects water ingress, it controls the relay 5a to interrupt the current flowing through the relay 5a. By interrupting the current flowing through the relay 5a, the current flowing through the inter-unit connection line 3 is suppressed. In S2, the control unit 100b collects logs based on the current suppressed by the process in S1. In S3, after a predetermined time has elapsed until log collection is complete, the control unit 100b interrupts the current flowing through the relay 5b. The control unit 100b may also turn off the breaker 6.

[0034] In the second modified example, the control unit 100b can collect log information related to the power supply system 1b when flooding occurs, while suppressing the generation of hydrogen produced by the electrolysis of water.

[0035] The embodiments and modifications described above can be combined.

[0036] <Note 1> A battery unit group (10a, 10b) is formed by stacking multiple battery modules (11) electrically in series, with the polarity aligned in the vertical direction. A connecting wire (3) connects multiple battery units (10) in series, The connection line (3) is provided at a position higher than the battery unit group (10a, 10b), and includes a shut-off section (6, 5a) that shuts off the connection line (3) when water ingress is detected. Power supply system (1). [Explanation of Symbols]

[0037] 1. Power supply system 1a. Power supply system 2. Positive electrode wire 3. Inter-unit connection cable 4. Negative electrode wire 5. Relay 5a Relay 5b Relay 6. Circuit breaker 7. Fuse 8. Positive output terminal 9. Negative output terminal 10. Battery Unit 10a ··First Battery Unit 10b · Second Battery Unit 11a ··Battery module 11b ··Battery module 11c Battery Module 11d ··Battery module 11e Battery Module 11f ··Battery module 11g battery module 11h ··Battery module 12a·Positive electrode 12b...Positive electrode 13a··Negative electrode 13b··Negative electrode 20...Resistor 100 Control Unit 100a Control Unit 100b Control Unit 300 unit inter-unit connection cable 400 Control Unit 500 Power System R1...Flood area R2·Flood area W1 Short-circuit path W2 Short-circuit path

Claims

1. A group of battery units, each consisting of multiple battery modules electrically stacked in series, arranged with their polarity aligned in the vertical direction, A connecting wire for connecting multiple battery units in series, The aforementioned connection line includes a shut-off section provided at a higher position than the battery unit group, which shuts off the connection line when water ingress is detected, The system includes a log collection unit that receives power from the battery unit group and records the operation of the battery unit group and the cutoff unit, The aforementioned blocking section is It includes a first relay, a second relay and a resistor arranged in parallel with the first relay, When the aforementioned flooding is detected, the first relay is controlled to interrupt the current passing through the first relay, thereby suppressing the current flowing through the connecting wire. After a predetermined time has elapsed until the log collection by the log collection unit is completed, the second relay is controlled to interrupt the current passing through the second relay, thereby disconnecting the connecting wire. Power supply system.

2. The interruption unit includes a circuit breaker, and when the current passing through the second relay is interrupted, it turns off the circuit breaker. The power supply system according to claim 1.

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