Power supply system

Abstract

The present invention provides a power supply system that is easy to transport to the installation site and install, and that is easy to prevent water ingress from the wiring entry point. [Solution] The power supply system includes a first housing housing a power converter and a second housing housing a storage battery, and the first housing is fixed integrally with the second housing when positioned above the second housing.

Description

Technical Field

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

Background Art

[0002] A power supply system combining a photovoltaic power generation system and a power storage system is known. For example, Patent Document 1 below discloses a system including a solar cell, a storage battery, and a power conditioner. The power conditioner converts DC power generated by the solar cell into AC power and supplies it to a load, and also charges the storage battery with the generated power of the photovoltaic power generation.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As shown in Figure 1, one configuration of the power supply system is one in which the power conditioner (hereinafter referred to as PCS) 902 and the battery 904 are separated. The battery 904 is installed in the ground, the photovoltaic (PV) modules 906 are installed on the roof or elsewhere, and the PCS 902 is mounted on the wall or frame of the building. The PCS 902 converts the power generated by the PV modules 906 (DC power) into AC power and supplies it to the power switch 908. The power switch 908 is, for example, a relay switch. The power switch 908 receives control from an external source and switches the connection between the PCS 902 and the grid 914. Regarding the connection between the PCS 902 and the distribution board 910, the power switch 908 includes a path (wiring) that permanently connects the two. In other words, while the PV module 906 is generating power, the output power of the PCS 902 is output to the distribution board 910, allowing the load 912 to be operated without using commercial power supplied from the grid 914. If there is surplus power generated by the PV module 906, it is also possible to supply (sell) the surplus power to the grid 914. The storage battery 904 is a rechargeable secondary battery. The storage battery 904 is charged by the DC voltage (charging voltage) generated by the PCS 902, which is converted from the AC power of the grid 914. The storage battery 904 is also charged by the DC voltage (charging voltage) generated by the PCS 902, which is converted from the DC power of the PV module 906. The discharge power of the storage battery 904 is converted to AC power by the PCS 902 and supplied to the distribution board 910 via the power switch 908. This allows the load 912 to be operated without using commercial power supplied from the grid 914.

[0005] The power supply system 900 shown in Figure 1 has the following advantages: (a) and (b). (a) Since the PCS902 and the battery 904 are separate, it is easy to transport them to the installation site. (b) Electrical wiring (hereinafter simply referred to as wiring) can be introduced into the PCS902 from the bottom of the PCS902, making it easy to prevent water from entering through the wiring introduction point.

[0006] On the other hand, the power supply system 900 has the following disadvantages: (c), (d), and (e). (c) At the installation site, a wall or frame for mounting the PCS902 and the work required for its installation are necessary, and anchors must be driven into the wall, so reinforcement may be necessary depending on the strength of the wall. (d) Wiring work is required at the installation site to connect the PCS902 and the battery 904. (e) Because the wiring connecting the battery 904 and PCS902 is exposed, a noise filter must be installed to reduce interference from the wiring, which increases the number of components.

[0007] As a countermeasure to these shortcomings, the power supply system 920 shown in Figure 2 can be considered. In the power supply system 920, the PCS 902 and the battery 904 are housed in a single enclosure 922. The power supply system 920 functions similarly to the power supply system 900. This eliminates the need for (c), (d), and (e) above. However, the power supply system 920 has the following shortcomings: (f) and (g). (f) Because the enclosure 922 that houses the PCS 902 and the battery 904 is heavy, transporting it to the installation site and installing it is not easy. (g) A separate structure will be required to prevent water from entering through the wiring entry point.

[0008] Therefore, the purpose of this disclosure is to provide a power supply system that is easy to transport to the installation site and to install, and that is easy to prevent water ingress from the wiring entry point. [Means for solving the problem]

[0009] A power supply system relating to a certain aspect of this disclosure includes a first housing housing a power converter and a second housing housing a battery, wherein the first housing is fixed integrally with the second housing when positioned above the second housing. [Effects of the Invention]

[0010] According to this disclosure, it is possible to provide a power supply system that is easy to transport to the installation site and install, and that is easy to prevent water ingress from the wiring entry point. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a block diagram showing the configuration of a conventional power supply system. [Figure 2] Figure 2 is a block diagram showing the configuration of a conventional power supply system that includes the PCS and battery in a single enclosure. [Figure 3] Figure 3 is a block diagram showing the configuration of a power supply system according to an embodiment of this disclosure. [Figure 4] Figure 4 is a rear view of the power supply system according to the first modified example. [Figure 5] Figure 5 is a right side view of the power supply system shown in Figure 4. [Figure 6] Figure 6 is a rear view of the power supply system according to the second modified example. [Figure 7] Figure 7 is a right side view of the power supply system shown in Figure 6. [Figure 8] Figure 8 is a rear view of the power supply system according to the third modified example. [Figure 9] Figure 9 is a right side view showing the power supply system shown in Figure 8. [Modes for carrying out the invention]

[0012] [Description of Embodiments in this Disclosure] The embodiments of this disclosure are listed below for explanation. At least some of the embodiments described below may be combined in any way.

[0013] (1) The power supply system according to the first aspect of the present disclosure includes a first housing that houses a power conversion device and a second housing that houses a storage battery. The first housing is fixed integrally with the second housing in a state where it is disposed above the second housing. Thereby, when installing the power supply system, the carrying-in and installation work to the installation location is facilitated. Further, installation on a wall or a pedestal becomes unnecessary, and the installation space becomes smaller.

[0014] (2) In the above (1), the power supply system may further include wiring for connecting the storage battery and the power conversion device, and the wiring may be housed in the first housing and the second housing. Thereby, the wiring for connecting the storage battery and the power conversion device can be housed inside the housing, and the noise filter for reducing the interference wave from the wiring can be simplified.

[0015] (3) In the above (1) or (2), the power supply system may further include a monitoring device for monitoring the state of the storage battery. The monitoring device may be housed in the first housing, the second housing or a third housing. When the monitoring device is housed in the second housing, the monitoring device may be disposed above the storage battery. When the monitoring device is housed in the third housing, the third housing may be disposed between the first housing and the second housing. Thereby, a power supply system having a monitoring device can be realized without increasing the installation space, and the wiring between the power conversion device and the monitoring device, and the wiring between the monitoring device and the storage battery can be shortened.

[0016] (4) In the above (3), the monitoring device may connect or disconnect the connection between the storage battery and the power conversion device according to the state of the storage battery, and may prevent inrush current when connecting the storage battery and the power conversion device. Thereby, a power supply system having the function of a BMS (Battery Management System) can be realized.

[0017] (5) In any one of (1) to (4) above, the first enclosure may have a recess on its back or side and a plane located above the recess, and the plane may have an opening for introducing wiring into the first enclosure. This allows wiring to be inserted into the first enclosure from the bottom side of the first enclosure even when the first enclosure is stacked on top of the second enclosure, and makes it easy to prevent water from entering through the opening for introducing wiring into the first enclosure.

[0018] (6) In (5) above, the plane may further have a first end located on the front side of the first housing and a second end located on the rear side of the first housing, and the distance between the first end and the bottom surface of the first housing may be smaller than the distance between the second end and the bottom surface of the first housing. This makes it easier for the worker to see the insertion opening and facilitates wiring work.

[0019] (7) In any one of (1) to (4) above, the first housing may have a protrusion on its back or side and a flat surface located below the protrusion, and the flat surface may have an opening for introducing wiring into the first housing. This allows wiring to be inserted into the first housing from below even when the first housing is stacked on top of the second housing, and makes it easy to prevent water from entering through the opening for introducing wiring into the first housing.

[0020] (8) In (7) above, the plane may further have a first end and a second end, the distance between the first end and the back of the first housing may be smaller than the distance between the second end and the back, and the distance between the first end and the bottom surface of the first housing may be smaller than the distance between the second end and the bottom surface. This makes it easier for the worker to see the insertion opening and facilitates wiring work.

[0021] [Details of the embodiments of this disclosure] In the following embodiments, identical parts are assigned the same reference numeral. Their names and functions are also identical. Therefore, detailed descriptions of them will not be repeated.

[0022] (System Configuration) Referring to Figure 3, the power supply system 100 according to the embodiment of this disclosure includes a power converter 110, a monitoring device 112, a battery 114, and a PV module 116. The power converter 110, the monitoring device 112, and the battery 114 are housed in enclosures 120, 122, and 124, respectively. Enclosures 120 through 124 are stacked so that enclosure 124 is at the bottom and enclosure 120 is at the top, and are arranged outdoors. Enclosure 124 is fixed to a base 126 (made of concrete, etc.) installed on the ground via anchor bolts or the like. Enclosures 120 through 124 are firmly fixed to each other and integrated together by screws or the like.

[0023] The housings 120 and 124 are formed of conductive material such as metal. The power converter 110 and the battery 114 are connected by wiring (see solid and dashed lines) via the monitoring device 112, and these wires are housed inside the housings 120 and 124.

[0024] The power converter 110 is connected to the PV module 116 and to the battery 114 via the monitoring device 112. The PV module 116 consists of multiple series-connected solar cells arranged on a plane and sealed using tempered glass or the like. The PV module 116 functions as a DC power source. The battery 114 is a rechargeable secondary battery. The power converter 110 is also connected to the grid 134 via a power switch 130. The power switch 130 is, for example, a relay switch that receives external control and connects the power converter 110 to the grid 134. Regarding the connection between the power converter 110 and the distribution board 136, the power switch 130 includes a path (wiring) that permanently connects the two.

[0025] The power converter 110 is, for example, a PCS (Power Conditioning System) and has a bidirectional DC / AC conversion function and a bidirectional DC / DC conversion function. The DC / AC conversion function and the DC / DC conversion function are realized by, for example, a bridge circuit using multiple semiconductor switching elements (such as FETs (Field Effect Transistors)). The power converter 110 includes a control unit that controls each switching element (for example, PWM (Pulse Width Modulation) control) to realize the power conversion function. The control unit monitors the current value with a current measuring unit 132 and enables grid connection with the grid 134 and independent operation in the event of a power outage in the grid 134 via a power switch 130.

[0026] The power converter 110 converts DC power supplied from the PV module 116 or from the battery 114 via the monitoring device 112 into AC power and outputs it to the power switch 130. If the power converter 110 is connected to the grid 134 by the power switch 130, the AC power generated by the power converter 110 is used by the load 138 via the distribution board 136, with surplus power supplied to the grid 134 (sold electricity) and insufficient power supplied from the grid 134 (purchased electricity). If the power converter 110 is not connected to the grid 134 by the power switch 130, the AC power generated by the power converter 110 is used only by the load 138 (standalone operation). If the power converter 110 is connected to the grid 134 by the power switch 130, the power converter 110 converts the AC power input from the grid 134 via the power switch 130 into DC power to generate the charging voltage for the battery 114 and charges the battery 114. The power converter 110 can also generate the charging voltage for the battery 114 from the power generated by the PV module 116 and supply it to the battery 114 to charge it.

[0027] The monitoring device 112 has a protection function that monitors the status of the battery 114 and disconnects the connection between the battery 114 and the power converter 110 as needed, and a function to prevent inrush current when connecting the battery 114 to the power converter 110. Each of the protection function and the inrush current prevention function can be implemented by an electrical circuit. Although Figure 3 shows the monitoring device 112 housed in the housing 122, it is not limited to this. The monitoring device 112 may also be housed in the housing 120 or the housing 124.

[0028] When installing the power supply system 100, each of the housings, from housing 120 to housing 124, is transported to the installation site. First, housing 124 is fixed to the base 126 installed on the ground outside the house via anchor bolts or the like. Next, housing 122 is placed on top of housing 124, and housing 120 is placed on top of housing 122, and housings 120 to 124 are fixed to each other with screws or the like. Therefore, the power supply system 100 is easier to transport to the installation site and to install than the power supply system 920 shown in Figure 2. In addition, the power supply system 100 does not require installation on a wall or frame like the power supply system 900 shown in Figure 1, and the overall installation space is smaller.

[0029] As described above, the wiring connecting the power converter 110, the monitoring device 112, and the battery 114 is housed inside the enclosure 124, from the enclosure 120. This simplifies the noise filtering required to reduce interference from the wiring. In other words, instead of expensive, high-performance noise filters, inexpensive and simple noise filters can be used.

[0030] As described above, the power supply system 100 includes a monitoring device 112 for monitoring the status of the battery 114. The monitoring device 112 may be housed in the housing 122 on its own, or in the housing that houses the power converter 110 or the battery 114. In either case, the monitoring device 112 is located above the battery 114. This allows for shorter wiring between the power converter 110 and the monitoring device 112, and between the monitoring device 112 and the battery 114.

[0031] As described above, the power supply system 100 includes a monitoring device 112. This makes it possible to realize a power supply system with BMS functionality.

[0032] (First variation) As shown in Figure 1, in the power supply system 100, the power converter 110 is connected by wiring to the PV module 116, power switch 130, and current measuring unit 132 located outside the enclosure. Since the power supply system is installed outdoors, measures are needed to prevent water ingress from rainwater and other sources into the enclosure housing the electrical circuits at the wiring connection points. The power supply system according to the first modified example has a structure to prevent water ingress.

[0033] Referring to Figures 4 and 5, the power supply system 200 according to the first modified example includes a housing 202 and a housing 204. Housing 202 includes a power converter 110, and housing 204 includes a battery 114. The power supply system 200 may also include a monitoring device having the function of a BMS, in which case the monitoring device is housed in housing 202 or housing 204.

[0034] The housings 202 and 204 are made of a conductive material such as metal. Housing 204 is fixed to a base 126 installed on the ground via anchor bolts or the like, similar to housing 124 shown in Figure 3. The power converter 110 housed in housing 202 and the storage battery 114 housed in housing 204 are connected by wiring (not shown), and this wiring is housed inside housings 202 and 204. Recesses are formed in the lower part of housing 202 and the upper part of housing 204, and when housing 202 is placed on top of housing 204, a recess 206 is formed on the back of the power supply system 200.

[0035] Above the recess 206, a flat surface 208 provided on the housing 202 is positioned. That is, the upper part of the recess 206 is defined by the flat surface 208. An insertion port 210 for introducing the wiring 212 into the housing 202 is formed in the flat surface 208. The wiring 212 is connected to the power conversion device 110 through the insertion port 210. That is, the wiring 212 is inserted into the insertion port 210 from below the insertion port 210, and the upper part of the insertion port 210 is inside the housing 202. Thereby, even when the housing 202 is stacked on the housing 204, the wiring 212 can be inserted into the housing 202 from the bottom surface of the housing 202, and it is possible to easily prevent flooding such as rainwater from the insertion port 210.

[0036] Referring to FIG. 5, the flat surface 208 is arranged inclined from the horizontal (that is, it forms a predetermined angle greater than 0 with respect to the horizontal plane). Specifically, the flat surface 208 has a first end portion 208a and a second end portion 208b. The first end portion 208a is located on the front surface 202a side of the housing 202, and the second end portion 208b is located on the rear surface 202b side of the housing 202. And the shortest distance (hereinafter simply referred to as distance) L1 between the first end portion 208a and the bottom surface of the housing 202 is smaller than the distance L2 between the second end portion 208b and the bottom surface of the housing 202 (L1 < L2). Thereby, when the housing 202 and the housing 204 are stacked and arranged at the installation site, the second end portion 208b becomes higher than the first end portion 2′08a, so that an operator performing wiring work on the rear surface of the power supply system 200 can easily visually recognize the insertion port 210. Therefore, the wiring work to the insertion port 210 becomes easy.

[0037] (Second Modified Example) As a first modified example, in order to prevent flooding in the power supply system, the case where a recess is provided on the rear surface has been described, but it is not limited thereto. The power supply system according to the second modified example has a structure different from that of the first modified example in order to prevent flooding.

[0038] Referring to Figures 6 and 7, the power supply system 220 according to the second modified example includes a housing 222 and a housing 224. Housing 222 includes a power converter 110, and housing 224 includes a battery 114. The power supply system 220 may also include a monitoring device having the function of a BMS, in which case the monitoring device is housed in housing 222 or housing 224.

[0039] The housings 222 and 224 are made of a conductive material such as metal. Housing 224 is fixed to a base 126 installed on the ground via anchor bolts or the like. The power converter 110 housed in housing 222 and the storage battery 114 housed in housing 224 are connected by wiring (not shown), and this wiring is housed inside housings 222 and 224. Housing 222 has a protrusion 226 on its rear surface, and when housing 222 is placed on housing 224, the protrusion 226 is located on the rear surface of the power supply system 220.

[0040] A flat surface 228 is positioned below the protrusion 226. An insertion opening 230 is formed in the flat surface 228 for introducing the wiring 212 into the housing 222. The wiring 212 is connected to the power converter 110 through the insertion opening 230. That is, the wiring 212 is inserted into the insertion opening 230 from below, and the area above the insertion opening 230 is inside the protrusion 226. This allows the wiring 212 to be inserted into the housing 202 from below when the housing 222 is stacked on top of the housing 224, and makes it easy to prevent water from entering through the insertion opening 230, such as rainwater.

[0041] Referring to FIG. 7, the plane 228 is disposed at an inclination from the horizontal. Specifically, the plane 228 has a first end 228a and a second end 228b, and the distance between the first end 228a and the rear surface of the housing 222 (0 in FIG. 7) is smaller than the distance between the second end 228b and the rear surface of the housing 222. And the distance L3 between the first end 228a and the bottom surface of the housing 222 is smaller than the distance L4 between the second end 228b and the bottom surface of the housing 222 (L3 < L4). Thus, when the housing 222 and the housing 224 are stacked and arranged at the installation site, the second end 228b is higher than the first end 228a, so that an operator performing wiring work on the rear surface of the power supply system 220 can easily visually recognize the insertion port 230. Therefore, the wiring work to the insertion port 230 becomes easy.

[0042] (Third Modified Example) In the second modified example described above, the convex portion 226 protrudes from the rear surface of the power supply system 220, but it is not limited to such a shape. The power supply system according to the third modified example is provided with a convex portion so as not to protrude from the rear surface of the power supply system.

[0043] Referring to FIGS. 8 and 9, the power supply system 240 according to the third modified example includes a housing 242 and a housing 244. The housing 242 includes the power conversion device 110, and the housing 244 includes the storage battery 114. In the power supply system 240, the depth of the housing 242 is smaller than the depth of the housing 244. In the space 254 formed when the housing 242 and the housing 244 are stacked so that their front surfaces are aligned, for example, a radiator for cooling heat-generating components included in the power conversion device 110 can be arranged. The power supply system 240 may include a monitoring device having the function of the BMS. In that case, the monitoring device is housed in the housing 242 or the housing 244.

[0044] The housing 242 and the housing 244 are formed of a conductive member such as metal. The housing 244 is fixed to the base 126 installed on the ground via an anchor bolt or the like. The power conversion device 110 housed in the housing 242 and the storage battery 114 housed in the housing 244 are connected by wiring (not shown), and the wiring is housed inside the housing 242 and the housing 244. The housing 242 has a convex portion 246 at the lower part of the back surface, and the housing 244 has a concave portion 252 at the upper part of the back surface. When the housing 242 is disposed on the housing 244, the concave portion 252 is located below the convex portion 246 on the back surface of the power supply system 240.

[0045] A flat surface 248 is disposed at the lower part of the convex portion 246. An insertion port 250 for introducing the wiring 212 into the housing 242 is formed in the flat surface 248. The wiring 212 is connected to the power conversion device 110 through the insertion port 250. That is, the wiring 212 is inserted into the insertion port 250 from below the insertion port 250, and the upper part of the insertion port 250 is inside the convex portion 246. Also, a concave portion 252 is located below the convex portion 246. Thereby, in a state where the housing 242 is stacked on the housing 244, the wiring 212 can be inserted into the housing 242 from below, and it is possible to easily prevent water such as rainwater from entering through the insertion port 250.

[0046] Referring to FIG. 9, the flat surface 248 is disposed inclined from the horizontal. Specifically, the flat surface 248 has a first end portion 248a and a second end portion 248b, and the distance (0 in FIG. 9) between the first end portion 248a and the back surface of the housing 242 is smaller than the distance between the second end portion 248b and the back surface of the housing 242. And the distance L5 between the first end portion 248a and the bottom surface of the housing 242 is smaller than the distance L6 between the second end portion 248b and the bottom surface of the housing 242 (L5 < L6). Thereby, when the housing 242 and the housing 244 are stacked and disposed at the installation site, the second end portion 248b becomes higher than the first end portion 248a, so that an operator performing wiring work on the back surface of the power supply system 240 can easily visually recognize the insertion port 250. Therefore, the wiring work to the insertion port 250 becomes easy.

[0047] In the power supply system 240, the protrusion 246 formed on the housing 242 does not protrude from the rear of the power supply system 240 (i.e., the rear of the housing 244). Therefore, the protrusion 246 does not interfere with wiring work on the rear of the power supply system. Even if the distance between the rear of housing 244 and the exterior wall of the house is the same as the distance between the rear of housing 224 (see Figure 7) and the exterior wall of the house, wiring work on the rear of the power supply system 240 is easier than that of the power supply system 220 (see Figure 7).

[0048] In the above, the first to third modifications show a case in which at least one of the protrusions and recesses is provided on the back of the power supply system to facilitate the introduction of wiring into the enclosure, but the invention is not limited to this. At least one of the protrusions and recesses may be provided on the right or left side of the power supply system as described above. In this case as well, the above-described effects can be achieved.

[0049] The above example shows a case where a recess 252 is formed on the upper part of the housing 244, but it is not limited to this. For example, if the protrusion 246 formed on the back of the housing 242 is separated from the bottom surface of the housing 242 (or the top surface of the housing 244 if stacked) by a predetermined distance or more, the top surface of the housing 244 will not interfere with wiring work, even without providing a recess 252 on the upper part of the housing 244, and no problems will occur. The predetermined distance should be a distance that does not make it difficult to insert wiring into the insertion opening 250.

[0050] In the above, the first to third modifications show a case where the power supply system includes two housings, but it is not limited to these. The power supply system may include three housings, as shown in Figure 3, or four or more housings. In that case, when all the housings are stacked, at least one of a protrusion and a recess is formed on the uppermost housing containing the power converter and the housing below it (second from the top), as shown in the first to third modifications.

[0051] In the above, the recess formed on the back of the housing is shown as being formed on a part of the width of the housing (see Figures 6 and 8), but it is not limited to this. The recess may be formed over the entire width of the housing. The same applies to the protrusion formed on the back of the housing; the protrusion may be formed over the entire width of the housing.

[0052] The present disclosure has been described above by describing embodiments, but the embodiments described above are illustrative and the present disclosure is not limited to the embodiments described above. The scope of the present disclosure is as indicated by each claim of the claims, with reference to the description of the detailed description of the invention, and includes all modifications within the meaning and scope equivalent to the wording contained herein. [Explanation of symbols]

[0053] 100, 200, 220, 240, 900, 920 Power Systems 110 Power converter 112 Monitoring equipment 114,904 Storage batteries 116,906 PV modules 120, 122, 124, 202, 204, 222, 224, 242, 244, 922 cabinets 126 base 130, 908 Power Switch 132 Current Measurement Unit 134, 914 lines 136, 910 Distribution board 138,912 load 202a front 202b back 206, 252 recesses 208, 228, 248 plane 208a, 228a, 248a 1st end 208b, 228b, 248b 2nd end 210, 230, 250 insertion slots 212 Wiring 226, 246 protrusions 254 Space 902 PCS Distances of L1, L2, L3, L4, L5, L6

Claims

1. A first enclosure housing a power converter, Including a second enclosure housing a battery, The first housing is a power supply system that is fixed integrally with the second housing when positioned above the second housing.

2. The system further includes wiring connecting the battery and the power converter, The power supply system according to claim 1, wherein the wiring is housed in the first housing and the second housing.

3. The system further includes a monitoring device for monitoring the state of the battery, The monitoring device is housed in the first housing, the second housing, or the third housing. When the monitoring device is housed in the second housing, the monitoring device is positioned above the battery. The power supply system according to claim 1 or 2, wherein, when the monitoring device is housed in the third housing, the third housing is positioned between the first housing and the second housing.

4. The aforementioned monitoring device is Depending on the state of the storage battery, the storage battery and the power converter are connected, or the connection between the storage battery and the power converter is disconnected. The power supply system according to claim 3, which prevents inrush current when connecting the storage battery and the power conversion device.

5. The first enclosure has, on its back or side, recessed and It has a plane located at the upper part of the recess, The power supply system according to claim 1 or claim 2, wherein the plane has an opening for introducing wiring into the first housing.

6. The aforementioned plane is The first end located on the front side of the first housing, It further comprises a second end located on the rear side of the first housing, The power supply system according to claim 5, wherein the distance between the first end and the bottom surface of the first housing is smaller than the distance between the second end and the bottom surface of the first housing.

7. The first enclosure has, on its back or side, The convex part, It has a plane located at the lower part of the convex portion, The power supply system according to claim 1 or claim 2, wherein the plane has an opening for introducing wiring into the first housing.

8. The aforementioned plane is The first end and, It further has a second end, The distance between the first end and the back of the first housing is smaller than the distance between the second end and the back. The power supply system according to claim 7, wherein the distance between the first end and the bottom surface of the first housing is smaller than the distance between the second end and the bottom surface.

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