Parts replacement method and power supply circuit

Abstract

To continue power supply to a load even when a component installed in a power supply line between a DC power supply device and the load is to be replaced.SOLUTION: A battery pack 10 is a DC power supply device which supplies DC power to a load 40. A fuse 20 is provided in the middle of a power supply line to the load 40. Fuse breakers 31 and 32 for cutting off an electrical circuit before and after the fuse 20 which is a component to be replaced are provided on the power supply line to the load 40. A maintenance box device 60 is detachably configured by a connector through a three pole beaker 70 with the power supply line so as to continue power supply to the load 40 by connection to the fuse 20 which is the component to be replaced in parallel.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a component replacement method and a power supply circuit.

Background Art

[0002] When supplying a DC power supply from a DC power supply device to a load, a circuit configuration may be used in which components such as a fuse element are provided in the power supply line between the DC power supply device and the load to prevent an abnormal current from flowing through the load and to prevent battery failure. And the components such as fuse elements may have a determined service life, and periodic replacement may be required to prevent problems due to aging deterioration or the like.

[0003] Here, when replacing a component provided on the power supply line, usually, the power supply from the DC power supply device to the load must be stopped once. However, depending on the type of load, it may not be possible to stop the power supply to the load, and it may be required to continue the power supply.

[0004] As a technique for eliminating such component replacement, for example, there is a technique disclosed in Patent Document 1. Patent Document 1 discloses a protection circuit that eliminates fuse replacement and allows the circuit to operate even after a fault recovery.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the technology described in Patent Document 1 above, an overcurrent / overheating protection element is used instead of a fuse to interrupt abnormal currents flowing into the load circuit. Therefore, if this overcurrent / overheating protection element needs to be replaced due to deterioration over time, the power supply to the load circuit will have to be interrupted anyway.

[0007] The object of the present invention is to provide a component replacement method and a power supply circuit that enable the continued supply of power to a load even when replacing components installed in the power supply line between a DC power supply device and a load. [Means for solving the problem]

[0008] A first aspect of the present invention is a component replacement method for replacing a component provided in a power supply line between a DC power supply device and a load, The process involves opening the circuit breaker of a bypass device that is detachably configured to connect to a power supply line via a first circuit breaker in order to continue supplying power to the load by being connected in parallel with the part to be replaced, The steps include connecting the bypass device in parallel with a circuit that includes the part to be replaced and a second circuit breaker for interrupting the electrical circuits before and after the part, A step of closing the first circuit breaker of the bypass device, The process of opening the second circuit breaker, The process of replacing a part that needs replacing with another part, The process of closing the second circuit breaker, The steps include opening the first circuit breaker of the bypass device, The process includes the step of removing the bypass device from the power supply line.

[0009] Furthermore, the component replacement method of the second aspect of the present invention is a fuse that melts when a current exceeding a set value flows through it, The bypass device includes at least one fuse.

[0010] Furthermore, in the third aspect of the present invention, the component replacement method is a three-pole breaker capable of interlocking and disconnecting the circuit between the load and the ground line in addition to the circuit before and after the component to be replaced. The first circuit breaker is a three-pole breaker configured to switch the connection state between the power supply line and the load and the ground line, in addition to the connection state between the power supply line and the bypass device when the bypass device is connected to the power supply line.

[0011] Furthermore, the power supply circuit in the fourth aspect of the present invention includes a DC power supply device that supplies DC power to a load, The part to be replaced is located in the power supply line between the DC power supply device and the load, A bypass device is configured to be detachably connected to the power supply line via a first circuit breaker in order to continue supplying power to the load by being connected in parallel with the part to be replaced, It also includes a second circuit breaker for interrupting the electrical circuits before and after the aforementioned component to be replaced.

[0012] Furthermore, in the fifth aspect of the present invention, the power supply circuit is a fuse that melts when a current exceeding a set value flows through the component to be replaced. The bypass device includes at least one fuse.

[0013] Furthermore, in the sixth aspect of the present invention, the power supply circuit is a three-pole breaker capable of interlocking and interrupting the circuit before and after the component to be replaced, as well as the circuit between the load and the ground line. The first circuit breaker is a three-pole breaker configured to switch the connection state between the power supply line and the load and the ground line, in addition to the connection state between the power supply line and the bypass device when the bypass device is connected to the power supply line. [Effects of the Invention]

[0014] According to the present invention, even when replacing components installed in the power supply line between the DC power supply device and the load, it is possible to continue supplying power to the load. [Brief explanation of the drawing]

[0015] [Figure 1] This is a diagram showing the circuit configuration of a power supply system according to an embodiment of the present invention. [Figure 2] This is a diagram for explaining the circuit configuration around a certain load. [Figure 3] This is a diagram showing the circuit configuration of a maintenance box device 60 used when replacing fuse 20 without interrupting the power supply to load 40. [Figure 4] This is a diagram showing the state where the maintenance box device 60 shown in FIG. 3 is connected to the power supply system in order to replace fuse 20. [Figure 5] This is a circuit diagram showing the connection relationship between fuse breakers 31, 32, load breaker 33, fuse 20, and fuse breakers 71, 72, load breaker 73, fuse 80 in the state where the maintenance box device 60 is connected to the power supply system. [Figure 6] This is a circuit diagram showing the state where the three-pole breaker of the maintenance box device 60 is changed from the open state to the closed state. [Figure 7] This is a circuit diagram showing the state where the three-pole breaker 30 is changed from the closed state to the open state. [Figure 8] This is a diagram for explaining the state of replacing fuse 20 with another part, fuse 20A. [Figure 9] This is a circuit diagram showing the state where the three-pole breaker 30 is changed from the open state to the closed state after replacing fuse 20 with fuse 20A. [Figure 10] This is a circuit diagram showing the state where the three-pole breaker 70 of the maintenance box device 60 is changed from the closed state to the open state. [Figure 11] This is a diagram for explaining the state of removing the maintenance box device 60 from the power supply line. [Figure 12] This is a circuit diagram for explaining a component replacement method in a power circuit using a two-pole breaker.

Embodiments for Carrying Out the Invention

[0016] Next, embodiments of the present invention will be described in detail with reference to the drawings.

[0017] Figure 1 shows the circuit configuration of a power supply system according to one embodiment of the present invention.

[0018] In this embodiment, the power supply system is configured to supply DC power from the battery pack 10 to multiple loads 40. Specifically, in this embodiment, the power supply system consists of a power supply circuit comprising the battery pack 10, a battery breaker 13, a fuse 20, and fuse breakers 31 to 33, and this power supply circuit supplies power to the loads 40.

[0019] Here, the battery pack 10 consists of a lithium-ion battery 11 and a fuse 12, and is a DC power supply device that supplies DC power of voltages such as 48V and 100V to the load 40, respectively. The fuse 12 is a circuit protection element built into the battery pack 10 and is configured to blow when a current exceeding a set value flows through it.

[0020] However, in the power supply system shown in Figure 1, since DC power is supplied to multiple loads 40 from a single battery pack 10, if a short circuit or other fault occurs in one of the loads 40, the fuse 12 will blow, and the supply of DC power to all loads 40 will stop.

[0021] Therefore, in the power supply system shown in Figure 1, a fuse 20 is provided for each of the loads 40, so that even if a short circuit or other fault occurs in one of the loads 40, the supply of DC power to all of the loads 40 will not be interrupted.

[0022] In Figure 1, similar circuits are configured on the power supply lines for each of the loads 40; however, in the following explanation, we will only use the circuit configuration for one load 40.

[0023] In the power supply system shown in Figure 1, periodic replacement of the fuse 20 is necessary to prevent problems caused by aging deterioration such as corrosion. Therefore, the fuse 20 is replaced periodically, for example, at predetermined intervals of several years.

[0024] However, if the load 40, which operates using the supplied DC power, is, for example, a building's security system, then it may not be permissible to interrupt the power supply to the load 40, even when replacing the fuse 20.

[0025] Therefore, in the power supply system of this embodiment, by using the component replacement method described below, power supply to the load 40 is maintained even when replacing the fuse 20 provided in the power supply line between the battery pack 10 and the load 40. In other words, the component replacement method in this embodiment makes it possible to replace the fuse 20 provided in the power supply line between the battery pack 10 and the load 40 without interrupting the power supply to the load 40.

[0026] In the power supply system shown in Figure 1, the DC power from the battery pack 10 is supplied to the power supply lines for each load 40 via the battery breaker 13.

[0027] A fuse 20 is provided in each power supply line between the battery pack 10 and the load 40. This fuse 20 may be a fuse with an alarm function or a fuse without an alarm function. In the following, we will describe the case where this fuse 20 is a part that is to be replaced. On the power supply line to each load 40, fuse breakers (circuit breakers) 31 and 32 are provided, respectively, to interrupt the circuit before and after the fuse 20 that is to be replaced.

[0028] Furthermore, load breakers 33 are provided between the load 40 and the ground line (ground wire).

[0029] Furthermore, in order to allow the fuse 20 to be replaced without interrupting the power supply to the load 40, a connector connection part 51 is provided on the battery pack 10 side of the fuse breaker 31, and a connector connection part 52 is provided on the load 40 side of the fuse breaker 32. In addition, a connector connection part 53 is provided between the load 40 and the load breaker 33, and a connector connection part 54 is provided between the load breaker 33 and the ground line. The method of using these connector connection parts 51 to 54 will be described later.

[0030] Here, the two fuse breakers 31 and 32 and the load breaker 33 are actually composed of one 3-pole breaker 30, as shown in Figure 2. Figure 2 is a diagram illustrating the circuit configuration around a single load. Here, a 3-pole breaker 30 means a breaker with 3 poles. Here, the number of poles refers to the number of electrodes (terminals) to which wiring can be connected, and a breaker with 3 poles means that it is configured to interrupt the current of 3 wires.

[0031] The two fuse breakers 31 and 32 and the load breaker 33 that make up the 3-pole circuit breaker 30 are configured to be able to switch in conjunction between an open state and a closed state.

[0032] In other words, as shown in Figure 2, the 3-pole circuit breaker 30 is a 3-pole circuit breaker that can interlock and interrupt the electrical circuits before and after the fuse 20, which is the component to be replaced, as well as the circuit between the load 40 and the ground line.

[0033] Next, Figure 3 shows the circuit configuration of the maintenance box device 60 used when replacing the fuse 20 without interrupting the power supply to the load 40.

[0034] The maintenance box device 60 consists of a three-pole circuit breaker 70 and a fuse 80. The three-pole circuit breaker 70 consists of two fuse breakers 71 and 72 and a load breaker 73.

[0035] In this embodiment, the component to be replaced is a fuse 20 that melts when a current exceeding a set value flows through it. Therefore, the maintenance box device 60 includes at least one fuse 80. The reason for including the fuse 80 in the maintenance box device 60 is to prevent abnormal current from flowing to the load 40 even when replacing the fuse 20. The fuse 80 is set to have a rated current of approximately the same as the fuse 20 to be replaced.

[0036] The maintenance box device 60 is a bypass device that is detachably connected to the power supply line via a 3-pole breaker 70 and a connector, in order to continue supplying power to the load 40 by being connected in parallel with the fuse 20, which is the component to be replaced. The 3-pole circuit breaker 70 is a 3-pole circuit breaker configured to switch the connection state between the power supply line and the maintenance box device 60, as well as between the load 40 and the ground line, when the maintenance box device 60 is connected to the power supply line.

[0037] Figure 4 shows the maintenance box device 60 shown in Figure 3 connected to the power supply system in this embodiment for the purpose of replacing the fuse 20. The maintenance box device 60 is connected to the connector connection parts 51 to 54 by, for example, a 4-pin connector, as shown in Figure 4.

[0038] Figure 5 shows the connection relationships between fuse breakers 31, 32, load breaker 33, and fuse 20, and fuse breakers 71, 72, load breaker 73, and fuse 80, when the maintenance box device 60 is connected to the power supply system.

[0039] Referring to Figure 5, it can be seen that the circuit in which fuse breakers 31 and 32 and fuse 20 are connected in series, and the circuit in which fuse breakers 71 and 72 and fuse 80 are connected in series are connected in parallel. It can also be seen that load breaker 33 and load breaker 73 are connected in parallel.

[0040] Herein, the component replacement method in this embodiment is a component replacement method for replacing a fuse 20 provided in the power supply line between a battery pack 10, which is a DC power supply device, and a load 40, and comprises the following steps.

[0041] (1) Set the 3-pole breaker 70 of the maintenance box device 60 to the open state. (2) The maintenance box device 60 is connected in parallel with the circuit that includes the fuse 20 and the 3-pole breaker 30, which are the parts to be replaced. (3) Set the 3-pole breaker 70 of the maintenance box device 60 to the closed state. (4) Open the 3-pole circuit breaker 30. (5) Replace fuse 20 with another part. (6) Close the 3-pole circuit breaker 30. (7) The 3-pole breaker 70 of the maintenance box device 60 is left open. (8) Remove the maintenance box device 60 from the power supply line.

[0042] Next, we will sequentially describe each step of the parts replacement method in this embodiment described above.

[0043] (1) First, the 3-pole breaker 70 of the maintenance box device 60 is opened, and (2) the maintenance box device 60 is connected in parallel to a circuit that includes the fuse 20, which is the part to be replaced, and fuse breakers 31 and 32 for interrupting the electrical circuits before and after the fuse 20.

[0044] In this way, the circuit configuration with the maintenance box device 60 connected is as shown in Figure 4. That is, the 3-pole breaker 30 is in the closed state, and the 3-pole breaker 70 is in the open state.

[0045] (3) Next, the 3-pole circuit breaker of the maintenance box device 60 is changed from the open state to the closed state. The circuit diagram in this state is shown in Figure 6.

[0046] (4) Next, the 3-pole circuit breaker 30 is changed from the closed state to the open state. The circuit diagram in this state is shown in Figure 7. Referring to the circuit diagram in Figure 7, it can be seen that because the 3-pole circuit breaker 30 is in the open state, no voltage is applied across both ends of the fuse 20.

[0047] (5) Next, as shown in Figure 8, fuse 20 is replaced with another component, fuse 20A. For example, if fuse 20 is fixed by a bolt, the bolt is removed, replaced with fuse 20A, and then the bolt is tightened to secure it. If fuse 20 is a plug-in type fuse, the time required to loosen and tighten the bolt is eliminated, and the replacement time can be shortened. As mentioned above, since the 3-pole breaker 30 is in an open state, no voltage is applied to both ends of fuse 20, so the fuse 20 can be replaced without performing live-wire work. Here, live-wire work refers to work in which components are attached or detached while current is flowing or voltage is applied.

[0048] (6) After replacing fuse 20 with fuse 20A, the 3-pole circuit breaker 30 is changed from the open state to the closed state. The circuit diagram in this state is shown in Figure 9. With the 3-pole circuit breaker 30 in the closed state, fuse 20A is connected between the battery pack 10 and the load 40.

[0049] (7) Subsequently, the 3-pole breaker 70 of the maintenance box device 60 is changed from the closed state to the open state. The circuit diagram in this state is shown in Figure 10. Referring to Figure 10, when the 3-pole breaker 70 is in the open state, the fuse 80 inside the maintenance box device 60 is disconnected from the power supply line and no current flows. In other words, all current flowing from the battery pack 10 to the load 40 goes through the fuse 20A.

[0050] (8) Then, as shown in Figure 11, the maintenance box device 60 is removed from the power supply line.

[0051] By performing steps (1) to (8) described above, the process of replacing fuse 20 with fuse 20A is completed.

[0052] In this embodiment, the power supply system is provided with a connector connected to pre-configured connector connection sections 51 to 54, allowing for easy connection of the maintenance box device 60 simply by connecting this connector to the maintenance box device 60. Furthermore, in this embodiment, the power supply system is provided with a 3-pole circuit breaker 30 on the power circuit side, and the maintenance box device 60 is also provided with a 3-pole circuit breaker 70 connected in parallel with the 3-pole circuit breaker 30, enabling switching between open and closed states with a single breaker operation.

[0053] Therefore, according to the component replacement method of this embodiment, even when replacing components such as a fuse 20 provided in the power supply line between the battery pack 10 and the load 40, the component replacement can be carried out with fewer operations and in a short time while continuing to supply power to the load 40.

[0054] Although the above explanation described the case where a 3-pole circuit breaker is used in the power supply circuit, the same component replacement method can be implemented in a power supply circuit using a 2-pole circuit breaker. The method for replacing components in such a power supply circuit using a 2-pole circuit breaker will be explained with reference to Figure 12.

[0055] In the power supply system shown in Figure 12, a two-pole circuit breaker 91 is provided to switch the circuits before and after the fuse 20, and a two-pole circuit breaker 92 is provided to switch the circuits before and after the load 40.

[0056] Therefore, when replacing the fuse 20 in such a power supply circuit, a maintenance box device 100 as shown in Figure 12 is used. The maintenance box device 100 is equipped with a two-pole circuit breaker 93 and a fuse 80, and is configured to be connected in parallel with the circuit of the two-pole circuit breaker 91 and fuse 20 via connector connection parts 55 and 56.

[0057] In the circuit configuration shown in Figure 12, the two-pole breaker 92 is kept in a closed state at all times, and component replacement is performed by the following process.

[0058] (1) The two-pole circuit breaker 93 of the maintenance box device 100 is left open. (2) The maintenance box device 100 is connected in parallel to a circuit that includes the fuse 20, which is the part to be replaced, and a two-pole breaker 91 for interrupting the electrical circuits before and after the fuse 20. (3) Close the two-pole breaker 93 of the maintenance box device 100. (4) The 2-pole circuit breaker 91 is left open. (5) Replace fuse 20 with another part. (6) Close the 2-pole circuit breaker 91. (7) The two-pole breaker 93 of the maintenance box device 100 is left open. (8) Remove the maintenance box device 100 from the power supply line. However, the power supply circuit configuration shown in Figure 12 requires two 2-pole circuit breakers 91 and 92, resulting in disadvantages such as an increase in the number of components and higher costs compared to the power supply circuit configuration shown in Figure 4, which only requires one 3-pole circuit breaker 30.

[0059] [Differentiation] In the above embodiment, the case in which the component to be replaced is a fuse was used as an example, but the present invention is not limited to such a case, and can be similarly applied when replacing other components installed in the power supply line between the DC power supply device and the load, such as DC / DC converters, changeover switches, and other various components.

[0060] Furthermore, although the above embodiment described a case in which an electrical circuit is opened and closed using a circuit breaker, the present invention is not limited to such a case, and the present invention can be similarly applied when an electrical circuit is opened and closed using a switch or other switch to replace components such as fuse elements. [Explanation of symbols]

[0061] 10 battery packs 11 Lithium-ion batteries 12 fuses 13. Battery breaker 20, 20A fuse 30 3-pole circuit breaker 31, 32 Fuse breaker 33. Load breaker 40 load 51-56 Connector connection part 60 Maintenance box device 70 3-pole circuit breaker 71, 72 Fuse breaker 73 Load breaker 80 fuses 91-93 2-pole circuit breaker 100 Maintenance box device

Claims

1. A method for replacing components installed in a power supply line between a DC power supply device and a load, The process involves opening the first circuit breaker of a bypass device that is detachably configured to connect to a power supply line via a first circuit breaker in order to continue supplying power to the load by being connected in parallel with the part to be replaced, The steps include connecting the bypass device in parallel with a circuit that includes the part to be replaced and a second circuit breaker for interrupting the electrical circuits before and after the part, The steps include: closing the first circuit breaker of the bypass device; The process of opening the second circuit breaker, The process of replacing a part that needs replacing with another part, The process of closing the second circuit breaker, The steps include opening the first circuit breaker of the bypass device, The steps include removing the bypass device from the power supply line, A method for replacing parts that includes the following features.

2. The component to be replaced is a fuse that melts when a current exceeding a set value flows through it. The bypass device includes at least one fuse. The method for replacing parts according to claim 1.

3. The second circuit breaker is a three-pole breaker capable of interlocking the connection between the load and the ground line, in addition to the connection between the component to be replaced and the load. The first circuit breaker is a three-pole breaker configured to switch the connection state between the power supply line and the load and the ground line, in addition to the connection state between the power supply line and the bypass device when the bypass device is connected to the power supply line. The method for replacing parts according to claim 1.

4. A DC power supply device that supplies DC power to a load, The part to be replaced is located in the power supply line between the DC power supply device and the load, A bypass device is configured to be detachably connected to the power supply line via a first circuit breaker in order to continue supplying power to the load by being connected in parallel with the part to be replaced, A second circuit breaker for interrupting the electrical circuits before and after the aforementioned component to be replaced, A power supply circuit is provided.

5. The component to be replaced is a fuse that melts when a current exceeding a set value flows through it. The bypass device includes at least one fuse. The power supply circuit according to claim 4.

6. The second circuit breaker is a three-pole breaker capable of interlocking the connection between the load and the ground line, in addition to the connection between the component to be replaced and the load. The first circuit breaker is a three-pole breaker configured to switch the connection state between the power supply line and the load and the ground line, in addition to the connection state between the power supply line and the bypass device when the bypass device is connected to the power supply line. The power supply circuit according to claim 4.

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