Power Switching Device

Abstract

To reduce a manufacturing cost by reducing the number of components.SOLUTION: A power switch device 1 includes a switch circuit 13, a signal output circuit 14, a control unit 15, a substrate 30, a casing 31, and an outer cover 32. The switch circuit 13 switches power to be supplied to a load device 200 between commercial power supplied from a commercial power grid 2 and autonomous power supplied from an autonomous power source 3. The signal output circuit 14 outputs, to the switch circuit 13, a switch signal for switching from the commercial power to the autonomous power and a switch signal for switching from the autonomous power to the commercial power. The control unit 15 controls the signal output circuit 14. The control unit 15 is mounted on the substrate 30. The casing 31 accommodates the switch circuit 13, the signal output circuit 14, and the substrate 30 with the control unit 15 mounted thereon. The outer cover 32 covers the casing 31. Further, at least the signal output circuit 14 is also mounted on the substrate 30.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a power switching device, and more particularly to a power switching device that switches the power supplied to a load device between commercial power from a commercial power system and self-generated power from a self-generated power source.

Background Art

[0002] Patent Document 1 describes a power conversion device including an orthogonal conversion means for converting DC power from an external DC power source into AC power, a connection relay for opening and closing the connection between the output of the orthogonal conversion means and a commercial power system, and a control means for controlling the orthogonal conversion means and the connection relay. [[ID=?]]

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the power conversion device of Patent Document 1, since the connection relay and the like are arranged at a location different from the control board equipped with the control means and wiring for connecting the connection relay and the like to the board is required, the number of components is large and it takes time and effort in manufacturing, which has been a factor increasing the manufacturing cost.

[0005] An object of the present disclosure is to provide a power switching device capable of reducing the number of components and reducing the manufacturing cost.

Means for Solving the Problems

[0006] Note: There seems to be a small error in the original text where "

先行技術文献

Prior Art Documents

Prior Art Literature

特許文献

Patent Documents

Patent Literature

[0007] The power switching device disclosed herein has the effect of reducing the number of parts and thereby lowering manufacturing costs. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a block diagram of a power switching device according to an embodiment of the present disclosure. [Figure 2] Figure 2 is an explanatory diagram illustrating the circuit board included in the power switching device described above. [Figure 3] Figure 3 is a perspective view showing the external appearance of the power switching device described above. [Figure 4] Figure 4 is a perspective view showing the same power switching device with the outer cover removed, exposing the inner cover and other components. [Figure 5] Figure 5 is a perspective view showing the same power switching device with the inner cover removed, exposing the circuit board cover and other components. [Figure 6] Figure 6 is a perspective view showing the same power switching device with the circuit board cover removed, exposing the circuit board and other components, as well as the removed circuit board cover. [Modes for carrying out the invention]

[0009] The figures described in the embodiments below are schematic diagrams, and the ratios of the size and thickness of each component do not necessarily reflect the actual dimensional ratios. Furthermore, the configurations described in the following embodiments are merely examples of this disclosure. This disclosure is not limited to the following embodiments, and various modifications are possible depending on the design, etc., as long as the effects of this disclosure can be achieved.

[0010] (1) Power supply system The power switching device 1 according to the embodiment of this disclosure works in cooperation with the commercial power grid 2 and the independent power source 3 to realize a power supply system 100 that supplies power to load equipment 200.

[0011] (1-1) Load equipment In this embodiment, the load device 200 is a device that operates on commercial power, such as a television or refrigerator. However, the load device 200 may be an electrical device other than a home appliance, or an electric vehicle that can be charged with commercial power, and its type is not limited.

[0012] (1-2) Commercial power system The commercial power grid 2 is supplied with commercial power generated by power companies and other power businesses. In this embodiment, the commercial power is AC power with an effective value of 100V or 200V.

[0013] (1-3) Independent power supply In this embodiment, the self-sufficient power source 3 includes a solar power generation system and supplies self-sufficient power generated by the solar power generation system in self-sufficient operation. The solar power generation system consists of, for example, solar panels that convert sunlight into electricity, a storage battery that stores the electricity from the solar panels, and a power station that converts the electricity from the solar panels or the storage battery from DC to AC. The self-sufficient power source 3 supplies self-sufficient power equivalent to commercial power (same voltage and same frequency) (in this embodiment, AC power with an effective value of 100V or an effective value of 200V, and a frequency of 50Hz or 60Hz).

[0014] However, the self - power supply 3 is not limited to solar power generation, and any type of system that can generate power independently when the commercial power system 2 experiences a power outage is acceptable.

[0015] The self - power supply 3 in this embodiment is configured to automatically supply self - power during the period when the commercial power system 2 is out of power. That is, the self - power supply 3 starts supplying self - power in response to a power outage in the commercial power system 2 and stops supplying self - power in response to the restoration of commercial power. However, at least one of the supply start and supply stop may be performed manually. Also, it is preferable for the self - power supply 3 to match the phase of the self - power with that of the commercial power, but it does not have to be matched.

[0016] (1 - 4) Power switching device As shown in FIG. 1, the power switching device 1 according to an embodiment of the present disclosure includes a commercial input unit 11, a self - input unit 12, a switching circuit 13, a signal output circuit 14, a control unit 15, and an output unit 16.

[0017] Commercial power from the commercial power system 2 is input to the commercial input unit 11. Self - power from the self - power supply 3 is input to the self - input unit 12.

[0018] The switching circuit 13 switches the power supplied to the load device 200 between commercial power from the commercial power system 2 and self - power from the self - power supply 3. The switching circuit 13 in this embodiment includes a commercial - side coil 13a, a self - side coil 13b, and a latching relay (not shown).

[0019] A voltage based on the commercial power from the commercial input unit 11 is applied to the commercial - side coil 13a via the signal output circuit 14 and the control unit 15. A voltage based on the self - power from the self - input unit 12 is applied to the self - side coil 13b via the signal output circuit 14. The latching relay switches the connection to the output unit 16 between the commercial input unit 11 and the self - input unit 12 by the excitation action of the commercial - side coil 13a and the self - side coil 13b.

[0020] The signal output circuit 14 outputs a switching signal to the switching circuit 13 to initiate the switching from commercial power to off-grid power and from off-grid power back to commercial power.

[0021] More specifically, the signal output circuit 14 outputs a first switching signal to the switching circuit 13 when the commercial power system 2 experiences a power outage. The first switching signal is a signal used to switch from commercial power to independent power.

[0022] Furthermore, when the commercial power system 2 is restored after a power outage, the signal output circuit 14 outputs a second switching signal to the switching circuit 13 under the control of the control unit 15. The second switching signal is a signal for switching from independent power to commercial power, and it is a signal that starts supplying commercial power after a predetermined time has elapsed since the supply of independent power was stopped. The predetermined time is, for example, 6 seconds, but it may be between 4 and 8 seconds, or it may be less than 4 seconds or more than 8 seconds. Details of the first switching signal and the second switching signal will be described later.

[0023] The signal output circuit 14 in this embodiment consists of a first relay 141 and a second relay 142. The first relay 141 includes a first coil 141a and contacts (not shown). The second relay 142 includes a second coil 142a and contacts (not shown).

[0024] In the first relay 141, a first DC voltage (DC12V: described later) based on commercial power from the commercial input unit 11 is applied to the first coil 141a via the control unit 15. The contacts of the first relay 141 close in response to the start of the application of the first DC voltage to the first coil 141a and open in response to the stop of the application.

[0025] Therefore, while commercial power is being supplied, a first DC voltage is applied from the first relay 141 to the commercial-side coil 13a. When the commercial power system 2 experiences a power outage, the application of the first DC voltage from the first relay 141 to the commercial-side coil 13a is stopped. When power is restored to the commercial power system 2 after a power outage, the control unit 15 restarts the application of the first DC voltage from the first relay 141 to the commercial-side coil 13a after a predetermined time (for example, 6 seconds) has elapsed since the start of the input of independent power to the independent input unit 12.

[0026] In the second relay 142, a voltage based on the self-sustaining power from the self-sustaining input unit 12 is applied to the second coil 142a. The contacts of the second relay 142 close when the application of the voltage based on the self-sustaining power to the second coil 142a begins, and open when the application stops.

[0027] Therefore, while commercial power is supplied, there is no input of independent power to the independent input unit 12, and consequently, no voltage based on independent power is applied from the second relay 142 to the independent coil 13b. When the commercial power system 2 experiences a power outage, the application of voltage based on independent power from the second relay 142 to the independent coil 13b begins as independent power is input to the independent input unit 12. When power is restored to the commercial power system 2 after a power outage, the application of voltage based on independent power from the second relay 142 to the independent coil 13b also stops as independent power input to the independent input unit 12 stops.

[0028] As can be seen from the above, the first switching signal in this embodiment is the falling edge of the voltage applied from the first relay 141 to the commercial-side coil 13a, and the rising edge of the voltage applied from the second relay 142 to the independent-side coil 13b. Furthermore, the second switching signal in this embodiment is the falling edge of the voltage applied from the second relay 142 to the independent-side coil 13b, and the rising edge of the voltage applied from the first relay 141 to the commercial-side coil 13a.

[0029] The control unit 15 controls the signal output circuit 14. When the commercial power system 2 is restored after a power outage, the control unit 15 causes the switching circuit 13 to output a second switching signal to the signal output circuit 14.

[0030] In this embodiment, the control unit 15 includes an AC / DC conversion circuit 151 that converts commercial power to AC / DC, and a timer circuit 152 that operates on the output of the AC / DC conversion circuit 151. However, the control unit 15 does not necessarily have to include the AC / DC conversion circuit 151.

[0031] In this embodiment, the AC / DC conversion circuit 151 outputs a first DC voltage of 5V and a second DC voltage of 12V based on AC100V commercial power. However, the voltage values ​​of the first DC voltage and the second DC voltage are not limited to 5V and 12V.

[0032] The timer circuit 152 operates with the first DC voltage from the AC / DC conversion circuit 151 and remains dormant during a power outage in the commercial power system 2. When commercial power is supplied, the timer circuit 152 performs the following operations.

[0033] In other words, when the commercial power system 2 is restored after a power outage, the timer circuit 152 starts measuring the elapsed time from the moment the self-sustaining power associated with the restoration of power is stopped. Then, when the measurement result (elapsed time) exceeds a threshold, the timer circuit 152 applies the second DC voltage from the AC / DC conversion circuit 151 to the first coil 141a.

[0034] The output unit 16 is connected to the commercial power input unit 11 or the independent power input unit 12 by the switching circuit 13, and outputs commercial power input from the commercial power input unit 11 or independent power input from the independent power input unit 12 to the load equipment 200.

[0035] This allows the operation of the load equipment 200 to be maintained by off-grid power even if the commercial power grid 2 experiences a power outage.

[0036] Furthermore, when commercial power is restored, the start of commercial power supply in response to the interruption of independent power supply is delayed by a predetermined amount of time, thereby ensuring a period of no power supply where neither independent power nor commercial power is available.

[0037] Even if the phase of the independent power supply 3 is adjusted in advance to match the phase of the commercial power supply, the commercial power immediately after power restoration may be out of phase with respect to the independent power supply from the independent input unit 12. Therefore, if the supply of commercial power is started at the same time as the supply of independent power is stopped, the operation of the load equipment 200 may become unstable.

[0038] According to the power switching device 1, when commercial power is restored, the supply of commercial power is resumed after a certain period of no power supply following the suspension of independent power supply, thus avoiding instability of the load equipment 200 associated with the switch from independent power to commercial power.

[0039] Furthermore, by pre-setting the phase of the independent power supply 3 to match the phase of the commercial power supply, it is possible to avoid instability of the load equipment 200 due to switching from commercial power to independent power supply in the event of a power outage in the commercial power system 2.

[0040] (2) Example of operation of a power switching device In the power switching device 1, currently, commercial power from the commercial power grid 2 is input to the commercial input unit 11, and there is no input from the independent power supply 3 to the independent input unit 12.

[0041] In the control unit 15, the AC / DC conversion circuit converts the voltage based on the commercial power from the commercial input unit 11 into a first DC voltage (DC 5V) and a second DC voltage (DC 12V) and supplies them to the timer circuit 152. The timer circuit 152 uses the first DC voltage as its power source and performs the following operations.

[0042] The timer circuit 152 starts timing operation when the voltage of the self-sustaining power changes to 0, and when the timing result reaches or exceeds a threshold (e.g., 6 seconds), it applies a second DC voltage to the first coil 141a.

[0043] While commercial power is supplied, the second DC voltage is applied to the first coil 141a, while no voltage is applied to the second coil 142a. Therefore, the first relay 141 remains ON and the second relay 142 remains OFF. Consequently, in the switching circuit 13, the voltages applied to the two coils 13a and 13b, one for commercial power and the other for independent power, are both 0, and the latching relay does not operate.

[0044] In this state, a voltage based on commercial power is applied to the commercial side coil 13a, while no voltage is applied to the independent side coil 13b. Therefore, the output unit 16 is connected to the commercial input unit 11, and commercial power is supplied to the load device 200.

[0045] Subsequently, suppose that the commercial power system 2 experiences a power outage, and the input from the commercial power system 2 to the commercial input unit 11 ceases. Accordingly, the input of independent power from the independent power source 3 to the independent input unit 12 begins. In response to the start of independent power input, the application of the second DC voltage to the first coil 141a ceases, and the application of a voltage based on the independent power to the second coil 142a begins.

[0046] Accordingly, the first relay 141 switches from ON to OFF, and the second relay 142 switches from OFF to ON. Therefore, in the switching circuit 13, the voltage applied to the commercial side coil 13a is 0, while a voltage based on commercial power is applied to the independent side coil 13b, causing the contacts of the latching relay to change. As a result, the output unit 16 is connected to the independent input unit 12 instead of the commercial input unit 11, and the output to the load equipment 200 switches from commercial power to independent power.

[0047] During the supply of independent power, the first relay 141 remains OFF and the second relay 142 remains ON, and the latching relay of the switching circuit 13 does not operate. Therefore, the output unit 16 remains connected to the independent input unit 12, and independent power is supplied to the load equipment 200.

[0048] Subsequently, when commercial power is restored, the input of commercial power from the commercial power system 2 to the commercial input unit 11 resumes, and the input of independent power from the independent power source 3 to the independent input unit 12 stops.

[0049] However, even when commercial power is restored, the control unit 15 controls the signal output circuit 14, so that the second DC voltage is not applied to the first coil 141a until a predetermined time (for example, 6 seconds) has elapsed since the off-power supply was shut off. On the other hand, in response to the off-power supply, the voltage applied to the second coil 142a is cut off, and the second relay 142 changes from ON to OFF.

[0050] Therefore, immediately after the restoration of commercial power, no voltage is applied to the two coils 13a and 13b on the commercial and independent sides in the switching circuit 13, and the output unit 16 remains connected to the independent input unit 12 (i.e., the state immediately before the restoration of power is maintained). However, since the independent power is shut off in response to the restoration of power, neither commercial nor independent power is supplied to the load equipment 200.

[0051] Meanwhile, in response to the restoration of commercial power, the output of the first DC voltage and the second DC voltage from the AC / DC conversion circuit 151 is resumed, and the timer circuit 152 becomes operational with the first DC voltage and detects that the voltage of the self-sustaining power has changed to 0, and starts timing operation. Then, in response to the timing result exceeding a threshold, the timer circuit 152 starts applying the second DC voltage to the first coil 141a, and the first relay 141 changes from OFF to ON.

[0052] When the first relay 141 is turned ON, a voltage is applied to the commercial power side coil 13a in the switching circuit 13. On the other hand, since no voltage is applied to the independent power side coil 13b, the latching relay operates, and the commercial power input section 11 is connected to the output section 16 instead of the independent power input section 12, and the output to the load equipment 200 is switched from independent power to commercial power.

[0053] For example, when commercial power system 2 is restored after an outage, if the independent power does not immediately stop and the first relay 141 and the second relay 142 turn ON simultaneously, the switching signal path is interrupted, and the output to the load equipment 200 does not switch to commercial power but remains at independent power.

[0054] (3) Structure of the power switching device The power switching device 1 includes a circuit board 30. A control unit 15 is mounted on the circuit board 30. In the power switching device 1 of this embodiment, among the various components (11-16, etc.) shown in Figure 1, the signal output circuit 14 (first relay 141 and second relay 142) and the control unit 15 (AC / DC conversion circuit 151 and timer circuit 152) are mounted on the circuit board 30 as shown in Figure 2.

[0055] By mounting the signal output circuit 14 and the control unit 15 on a single circuit board 30, wiring between the signal output circuit 14 and the control unit 15 becomes unnecessary. This reduces the number of components and the effort required for wiring connections, thereby lowering manufacturing costs.

[0056] However, as shown in Modification 2, the switching circuit 13 may also be mounted on the circuit board 30.

[0057] The first relay 141 and the second relay 142 are mounted on the upper right portion of the circuit board 30, while the AC / DC conversion circuit 151 and the timer circuit 152 are mounted on the lower right portion of the circuit board 30.

[0058] Furthermore, a first terminal block 30a is provided in the lower left corner of the circuit board 30, and a second terminal block 30b is provided in the lower right corner of the circuit board 30. The first terminal block 30a supports each terminal (not shown) of the multiple power lines 36 (see Figures 5 and 6) from the commercial power input section 11 and the independent power input section 12 to the circuit board 30. The second terminal block 30b supports each terminal (not shown) of the multiple signal lines 37 (see Figures 5 and 6) from the circuit board 30 to the switching circuit 13.

[0059] In Figure 2, the dotted arrows indicate the paths through which voltage based on commercial power from the commercial power grid 2 is transmitted, and the solid arrows indicate the paths through which voltage based on independent power from independent power source 3 is transmitted.

[0060] The voltage based on commercial power input to the commercial power input section 11 and the voltage based on independent power input to the independent power input section 12 are transmitted via multiple power lines 36 from the terminal block 30a in the lower left corner of the circuit board 30 to the wiring of the circuit board 30. These two voltages transmitted to the wiring of the circuit board 30 are then transmitted via the first relay 141 and the second relay 142 mounted on the upper left part of the circuit board 30 to the second terminal block 30b in the lower right corner of the circuit board 30, and further transmitted from the second terminal block 30b to the switching circuit 13 via multiple signal lines 37.

[0061] Furthermore, as shown in Figure 3, the power switching device 1 includes a housing 31 and an outer cover 32 that covers the housing 31. The housing 31 has a rectangular parallelepiped shape and is open on the front side. The housing 31 houses the circuit board 30 on which the signal output circuit 14 and control unit 15 are mounted, the switching circuit 13, and other elements. These other elements include a commercial input unit 11, a standalone input unit 12, and an output unit 16.

[0062] The outer cover 32 is attached to the front side of the housing 31 so as to be openable and closable. In this embodiment, the outer cover 32 is made of synthetic resin. The outer cover 32 has a dustproof function that prevents dust and dirt from entering the inside of the housing 31.

[0063] In the following, various elements within the enclosure 31 may be referred to as "internal components." An internal component is, for example, a load breaker 35 (see Figures 4-6) that can interrupt the wiring to the load equipment 200. The load breaker 35 can also be considered as the output unit 16 or a part thereof. If a distribution board (not shown) is interposed between the power switching device 1 and the load equipment 200, the load breaker 35 is not necessary.

[0064] Furthermore, as shown in Figure 4, the power switching device 1 also includes an inner cover 33 that covers the inside of the housing 31. With various internal components housed inside the housing 31, the inner cover 33 is attached to the front side of the housing 31, accessible from the open front side of the housing 31. The aforementioned outer cover 32 is attached so as to cover the inner cover 33 that has been attached to the front side of the housing 31.

[0065] Furthermore, the inner cover 33 is provided with a window 33a at a position corresponding to the load breaker 35 inside the housing 31. When the inner cover 33 is attached to the housing 31, the front side of the load breaker 35 is exposed through the window 33a of the inner cover 33.

[0066] In this embodiment, the inner cover 33 is made of metal such as iron, aluminum, or stainless steel. However, the inner cover 33 may be made of a fire-resistant material other than metal. The inner cover 33 has a fire spread prevention function that prevents the fire from spreading to the outer cover 32 in the event that the inner container catches fire.

[0067] Furthermore, the inner cover 33 also has an internal contact prevention function that prevents the user's hand from coming into contact with the internal components inside the housing 31 when the outer cover 32 is open. The inner cover 33 also functions as a support for the first terminal block 30a and the second terminal block 30b on the circuit board 30 mentioned above.

[0068] Furthermore, as shown in Figures 5 and 6, the power switching device 1 further includes a substrate cover 34 that covers the substrate 30. In this embodiment, the substrate cover 34 is made of metal, but it may be made of a conductive material other than metal (such as carbon). In other words, the material of the substrate cover 34 can be anything that can achieve electromagnetic shielding.

[0069] The circuit board cover 34 has a rectangular parallelepiped shape with an open rear side, and two notches 34a and 34b are formed at the left and right ends of the rear of the bottom surface. The left notch 34a functions as an entry point for multiple power lines 36 to be drawn from the commercial input section 11 and the standalone input section 12 to the circuit board 30 inside the circuit board cover 34. The right notch 34b functions as an exit point for multiple signal lines 37 to be drawn from the circuit board 30 inside the circuit board cover 34 to the switching circuit 13.

[0070] However, the number of notches formed in the circuit board cover 34 may be one or three or more. For example, all of the multiple power lines 36 and multiple signal lines 37 may pass through one of the two notches 34a and 34b, in which case the other of the two notches 34a and 34b is not necessary. In addition, another notch (not shown) may be formed in the circuit board cover 34 for wiring between other internal components and the circuit board 30. This makes it easy to wire and connect the circuit board 30 inside the circuit board cover 34 to the various internal components outside the circuit board cover 34.

[0071] (4) Variation 1 In Modification 1, the control unit 15 includes a processor and memory (neither of which are shown) instead of the timer circuit 152. The memory stores a program, and the processor performs the following processes according to the program in the memory.

[0072] In other words, the processor determines whether commercial power has been restored, and if commercial power has been restored, it further determines whether the independent power has stopped. If the independent power has stopped, the processor starts a timer (not shown) and then begins to periodically or irregularly determine whether the timer value has exceeded a threshold. If the timer value has exceeded the threshold, the processor switches the first relay 141 from OFF to ON by applying a second DC voltage from the AC / DC conversion circuit 151 to the first coil 141a.

[0073] According to Modification 1, the operation of the timer circuit 152 in the embodiment can be realized by software.

[0074] (5) Variation 2 In the modified example 2, in addition to the signal output circuit 14 and the control unit 15, a switching circuit 13 is also mounted on the circuit board 30.

[0075] According to the modified example 2, by further mounting the switching circuit 13 on the circuit board 30, the wiring between the switching circuit 13 and the control unit 15 becomes unnecessary, further reducing costs.

[0076] (6) Summary As described above, the power switching device (1) according to the first aspect of this disclosure comprises a switching circuit (13), a signal output circuit (14), a control unit (15), a circuit board (30), a housing (31), and a cover (outer cover 32). The switching circuit (13) switches the power supplied to the load equipment (200) between commercial power from the commercial power grid (2) and independent power from the independent power supply (3). The signal output circuit (14) outputs a switching signal to the switching circuit (13) to switch from the commercial power to the independent power and from the independent power to the commercial power. The control unit (15) controls the signal output circuit (14). The control unit (15) is mounted on the circuit board (30). The housing (31) houses a circuit board (30) on which a switching circuit (13), a signal output circuit (14), and a control unit (15) are mounted, and the cover (outer cover 32) covers the housing (31). Furthermore, at least the signal output circuit (14) is further mounted on the circuit board (30).

[0077] According to this embodiment, by mounting the signal output circuit (14) and the control unit (15) on a single circuit board (30), the number of components can be reduced, and manufacturing costs can be lowered.

[0078] In the second embodiment, the power switching device (1) further includes a switching circuit (13) mounted on the circuit board (30) as in the first embodiment.

[0079] According to this embodiment, further cost reductions can be achieved by mounting the switching circuit (13) on a single circuit board (30).

[0080] The power switching device (1) according to the third embodiment further comprises an inner cover (33) that covers the inside of the housing (31) in the first or second embodiment. The cover is an openable and closable outer cover (32) that covers the housing (31) covered by the inner cover (33).

[0081] According to this embodiment, by providing an inner cover (33) between the housing (31) and the outer cover (32), it is possible to prevent the spread of fire from the internal components inside the housing (31) to the outer cover (32). In addition, it is possible to prevent the user from coming into contact with the internal components when the outer cover (32) is open.

[0082] The power switching device (1) according to the fourth embodiment further comprises a substrate cover (34) that covers the substrate (30) in the third embodiment. The inner cover (33) covers the inside of the housing (31) that houses the substrate (30) covered by the substrate cover (34).

[0083] According to this embodiment, dust protection and noise reduction for the substrate (30) can be achieved by covering the substrate (30) with a substrate cover (34).

[0084] In the fifth embodiment of the power switching device (1), the substrate cover (34) has one or more notches (34a, 34b) for passing wiring between the substrate (30) and an element located inside the housing (31) and outside the substrate cover (34).

[0085] According to this embodiment, even if the substrate (30) is covered with a substrate cover (34), the substrate (30) inside the substrate cover (34) and the internal components outside the substrate cover (34) can be easily wired together.

[0086] In the sixth embodiment of the power switching device (1), in any of the first to fifth embodiments, the signal output circuit (14) outputs a first switching signal to the switching circuit (13) for switching from the commercial power to the independent power when the commercial power system (2) experiences a power outage.

[0087] According to this embodiment, even if the commercial power grid (2) experiences a power outage, the operation of the load equipment (200) can be maintained using off-grid power.

[0088] In the seventh embodiment of the power switching device (1), in the sixth embodiment, the control unit (15) causes the switching circuit (13) to output a second switching signal to the signal output circuit (14) when the commercial power system (2) is restored after the power outage. The second switching signal is a signal for switching from the independent power to the commercial power, and is a signal that starts the supply of the commercial power after a predetermined time has elapsed since the supply of the independent power was stopped.

[0089] According to this embodiment, when commercial power is restored, the start of commercial power supply is delayed in relation to the interruption of independent power supply, thereby ensuring a period of no power supply, and thus avoiding instability of load equipment (200) associated with the switch from independent power to commercial power. [Explanation of Symbols]

[0090] 1. Power switching device 2 Commercial power system 3 Independent power supply 13 Switching Circuit 14. Signal output circuit 15 Control Unit 30 circuit boards 31 cabinets 32 Cover (Outer cover) 33 Inner cover 34 Circuit board cover 34a, 34b Notches 100 Power supply systems 200 Load equipment

Claims

1. a switching circuit that switches the power supplied to the load device between commercial power from the commercial power system and independent power from the independent power source; a signal output circuit that outputs a switching signal to the switching circuit to cause the switching circuit to switch from the commercial power to the independent power and from the independent power to the commercial power; a control unit that controls the signal output circuit; a substrate on which the control unit is mounted; a housing that houses the switching circuit, the signal output circuit, and the board on which the control unit is mounted; a cover that covers the housing, At least the signal output circuit is further mounted on the substrate. Power switching device.

2. The switching circuit is further mounted on the substrate. The power switching device according to claim 1 .

3. further comprising an inner cover that covers the inside of the housing; the cover is an outer cover that can be opened and closed and covers the housing that is covered with the inner cover; The power switching device according to claim 1 or 2.

4. Further provided is a substrate cover that covers the substrate, the inner cover covers the inside of the housing that houses the board covered by the board cover; The power switching device according to claim 3 .

5. the board cover has one or more notches for routing wiring between the board and elements inside the housing and outside the board cover; The power switching device according to claim 4 .

6. When the commercial power system experiences a power outage, the signal output circuit outputs a first switching signal to the switching circuit for switching from the commercial power to the independent power. A power switching device according to any one of claims 1 to 5.

7. When the commercial power system recovers from the power outage, the control unit outputs to the signal output circuit a second switching signal, which is a signal for switching from the independent power to the commercial power, and which starts supplying the commercial power after a predetermined time has elapsed since the supply of the independent power was stopped. The power switching device according to claim 6.

Images