WO2017126486A1

WO2017126486A1 - Transformer for breaker circuit

Info

Publication number: WO2017126486A1
Application number: PCT/JP2017/001322
Authority: WO
Inventors: 島津　英一郎; 貴之小田
Original assignee: Ntn株式会社
Priority date: 2016-01-20
Filing date: 2017-01-17
Publication date: 2017-07-27
Also published as: JP2017131032A

Abstract

The present invention provides a transformer for a breaker circuit with which it is possible to actuate a breaker instantly to break a circuit in the event of an overcurrent such as with a short. The transformer for a breaker circuit (4) is provided with a primary coil (4a) and a secondary coil (4b). A main circuit (5) comprising a direct current circuit provided with a contact point (3a) of a circuit breaker (3) in which the contact point is opened and closed using an electromagnet is provided with the primary coil (4a), which is connected in series or in parallel with the contact point (3a). A sub circuit (6) on which is provided an electromagnetic coil (3b) for exciting the electromagnet of the circuit breaker (3) is provided with the secondary coil (4b), which is connected in series with the electromagnetic coil (3b). The winding count ratio of the primary coil (4a) and the secondary coil (4b) is set so that the current value flowing to the secondary coil (4b) is greater than the current value flowing to the primary coil (4a).

Description

Circuit breaker transformer

Related applications

This application claims the priority of Japanese Patent Application No. 2016-008709 filed on Jan. 20, 2016, which is incorporated herein by reference in its entirety.

The present invention relates to a transformer for making it possible to use a circuit breaker for short-circuit protection in a DC circuit, and more particularly to a transformer that operates a circuit breaker while functioning as a current limiting device. The present invention relates to a transformer that can effectively use a circuit breaker having a feature that the time until the circuit breaks is shortened as the value of the current flowing through the relay unit of the circuit breaker increases.

¡In order to protect equipment and people from electrical accidents such as short circuits and electrical leakage, electrical equipment must be provided with protective equipment that shuts off the circuit when a large current flows through the circuit. On the other hand, it is necessary for an electrical device to prevent the protective device from malfunctioning due to an inrush current that occurs when a switch, a circuit breaker, or the like is turned on / off or during a momentary power failure. For this reason, various protective devices such as fuses, circuit breakers, and relays are used in accordance with circuit specifications.

For example, in a DC circuit such as a high voltage DC circuit used for a quick charger for an electric vehicle, an arc discharge is generated by a switch operation. Therefore, when a circuit breaker is provided in this DC circuit, an unstable circuit break operation Will occur. For this reason, fuses are usually used because of the advantage that the circuit can be reliably interrupted for short circuit protection. However, since the fuse is damaged by fusing when it operates, it needs to be replaced every time the breaking operation is performed. For this reason, there is a demand for using protective devices other than fuses, and circuit breakers are often used.

Conventionally, when using a circuit breaker as a protective device, in order to prevent the inrush current due to a short circuit from exceeding the rated current of the circuit breaker, a method of suppressing an increase in current due to a short circuit by connecting an inductor called a current limiting coil in series Are known (for example, Patent Literature 1 and Non-Patent Literature 1).

International Publication No. 2015/015831 Pamphlet

However, the method of connecting an inductor called a current limiting coil in series with the circuit has a problem that it takes a long time until the circuit breaker operates.

An object of the present invention is to provide a transformer for a breaker circuit capable of breaking a circuit by operating a breaker instantaneously when an overcurrent such as a short circuit occurs.

A transformer for a breaker circuit according to one configuration of the present invention is a primary circuit provided by being connected in series or in parallel with the contact to a main circuit composed of a DC circuit provided with the contact of a circuit breaker that opens and closes a contact with an electromagnet. A secondary coil provided in series with the electromagnet coil in a secondary circuit provided with a coil and an electromagnet coil for exciting the electromagnet of the circuit breaker, and from a current value flowing through the primary coil Also, the turn ratio of the primary coil and the secondary coil is set so that the value of the current flowing through the secondary coil becomes large.

According to this configuration, the primary coil of the circuit breaker transformer is provided in the main circuit, the secondary coil is connected to the electromagnet coil of the circuit breaker, and the current flowing in the secondary coil is greater than the current value flowing in the primary coil. The turn ratio of the primary coil and the secondary coil is set so that the value becomes large. For this reason, electric power corresponding to a large current change generated in the main circuit due to the short circuit is supplied to the electromagnet coil of the circuit breaker via the breaker circuit transformer. At that time, the current value caused by the short circuit generated in the primary coil is further increased by supplying current to the electromagnet coil by changing the current in the transformer for the breaking circuit. Thereby, the interruption | blocking speed improves and a circuit breaker can be operated before a short circuit current becomes large too much. As a result, the influence of the inrush current on various devices on the primary side main circuit can be suppressed low.

Since the effect of inrush current can be kept low in this way, a circuit breaker can be used safely as a substitute for a fuse as a protective device for a short circuit in a main circuit to which a high voltage is applied. This solves the problem that the fuse must be replaced each time a short circuit occurs in the conventional circuit using the fuse as the protective device.

When the circuit breaker transformer is a cored transformer, a capacitor is provided in series or in parallel with the secondary coil so that the secondary coil is a resonant coil that resonates with the leakage flux of the primary coil. Also good. If a large current is input to the breaker circuit transformer, the core may be magnetically saturated and the breaker circuit transformer may not function. By making the secondary coil a resonant coil, even if the core can only store energy less than the breaking capacity of the circuit breaker, the leakage flux of the primary coil and the secondary coil resonate, eliminating the effects of magnetic saturation of the core can do.

Note that when magnetic saturation occurs, the entire core eventually becomes magnetically saturated. Magnetic saturation occurs when the power energy flowing in the coil is stored in the core in the form of magnetic energy. First, the portion where the primary coil is wound and the vicinity thereof are first magnetically saturated. If the magnetic flux generated in the primary coil flows smoothly to the secondary coil and electric power equivalent to the input is output from the secondary coil, magnetic saturation does not occur. Energy that is not extracted from the secondary coil is accumulated in the core and reaches saturation.

The core includes a core around which the primary coil and the secondary coil are wound. The core includes a first magnetic circuit through which a magnetic flux generated by a current flowing through the primary coil flows, and the first magnetic circuit, A second magnetic circuit in parallel is formed, and a permanent magnetic flux is applied to the second magnetic circuit that is reversely biased with respect to the magnetic flux generated when an inrush current flows through the primary coil. A magnet may be provided. When the permanent magnet is provided, the magnetic flux flowing through the first magnetic circuit and the magnetic flux flowing through the second magnetic circuit cancel each other by applying a magnetic flux that is reverse-biased by the permanent magnet, The magnetic flux density of the core is reduced. For this reason, even a small core with low energy storage capability is less likely to be magnetically saturated. Note that a metal tube or a short-circuited coil for preventing demagnetization of the permanent magnet due to the magnetic flux generated in the primary coil may be provided on the side surface of the permanent magnet.

An air gap may be provided in a portion of the core portion constituting the first magnetic circuit where the primary coil and the secondary coil are not wound. If the air gap is not provided, the magnetic flux generated by the permanent magnet does not pass through the core portion around which the primary coil and the secondary coil are wound, and the primary coil of the core portion constituting the first magnetic circuit and the There is a possibility of passing through a portion where the secondary coil is not wound. In this case, the reverse bias action of the magnetic flux generated by the permanent magnet is reduced. However, by providing the air gap, the magnetic flux generated by the permanent magnet can easily pass through the core portion where the primary coil and the secondary coil are wound, and the magnetic flux generated by the permanent magnet acts efficiently as a reverse bias.

A cored transformer having a winding ratio of the secondary coil to the primary coil of 1/3 or less, and the core of the cored transformer has a capacity capable of storing energy more than the breaking capacity of the circuit breaker. May be. In this case, magnetic saturation of the core can be prevented without using a secondary coil as a resonance coil as described above or providing a permanent magnet for applying a magnetic flux as a reverse bias.

A circuit breaker according to one aspect of the present invention includes the breaker transformer, and further includes a contact provided in the main circuit, an electromagnet that opens and closes the contact, and an electromagnet provided in the sub-circuit to excite the electromagnet. A circuit breaker having an electromagnet coil is provided.

Any combination of at least two configurations disclosed in the claims and / or the specification and / or drawings is included in the present invention. In particular, any combination of two or more of each claim in the claims is included in the present invention.

The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are for illustration and description only and should not be used to define the scope of the present invention. The scope of the invention is defined by the appended claims. In the accompanying drawings, the same reference numerals in a plurality of drawings indicate the same or corresponding parts.
FIG. 6 is an electric circuit diagram of an electric device provided with any one of the circuit breaker transformers according to the first to third embodiments of the present invention. It is a figure which shows schematic structure of the transformer for interruption | blocking circuits concerning the 1st Embodiment of this invention. It is a figure which shows schematic structure of the transformer for cutoff circuits concerning the 2nd Embodiment of this invention. It is a figure which shows schematic structure of the transformer for cutoff circuits concerning the 3rd Embodiment of this invention. It is a graph which shows a magnetic hysteresis curve. It is a figure which shows schematic structure of the transformer for virtual cutoff circuits.

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is an electric circuit diagram of an electric device 100 provided with an arbitrary one of circuit breaker transformers according to first to third embodiments of the present invention. The electric device 100 is, for example, a quick charger for an electric vehicle. The electric device 100 includes a device 1 such as a charger main body, and a DC power source 2, a circuit breaker 3, and a breaker circuit transformer 4 are provided along with the device 1. A circuit breaker 110 according to an embodiment of the present invention includes a circuit breaker 3 and a breaker circuit transformer 4. In the example of FIG. 1, some components of the device 1, the DC power supply 2, and the circuit breaker 3, and some components of the circuit breaker 4 are a main circuit 5 including a DC circuit. Are provided in series with each other. Specifically, the contact breaker 3a is included in the main circuit 5 as the partial component for the circuit breaker 3, and the primary coil 4a is included in the main circuit 5 as the partial component for the transformer 4 for the breaker circuit. include. The primary coil 4 a of the breaker circuit transformer 4 may be connected in parallel with the contact 3 a in the main circuit 5.

The direct current power source 2 is composed of, for example, a rectifier that rectifies alternating current into direct current. The DC power supply 2 may be a battery. When the electric device is a quick charger for an electric vehicle, the voltage of the main circuit 5 is a high voltage of several hundred volts or more.

The circuit breaker 3 is a complete electromagnetic type in which the contact 3a is removed by an electromagnet (not shown). For example, the complete electromagnetic circuit breaker 3 includes an electromagnet that attracts the movable iron core, a braking spring that applies a force opposite to the attracting direction by the electromagnet to the movable iron core, braking oil, and the like (not shown). ). However, an electromagnetic / thermal type may be used in combination with a thermal type in which the contact point 3a is removed by utilizing thermal deformation of the bimetal.

As described above, the contact 3 a is inserted in the main circuit 5. Normally, the contact 3a is closed. An electromagnet coil 3b that excites an electromagnet is connected to a subcircuit 6 that is a separate circuit from the main circuit 5.

The breaking circuit transformer 4 includes a primary coil 4 a inserted into the main circuit 5 and a secondary coil 4 b inserted into the sub circuit 6. The secondary coil 4 b and the electromagnetic coil 3 b are connected in series in the sub circuit 6. The cutoff circuit transformer 4 functions to supply a high current value to the electromagnet coil 3b by amplifying an inrush current caused by a short circuit or the like generated on the primary side and transmitting the amplified current to the secondary side.

Therefore, the number of turns N2 of the secondary coil 4b is made smaller than the number of turns N1 of the primary coil 4a so that the value of the current flowing in the secondary coil 4b is larger than the value of the current flowing in the primary coil 4a. In other words, the turn ratio (N1 / N2) between the primary coil 4a and the secondary coil 4b is set appropriately. The winding ratio (N1 / N2) is not particularly limited, but for example, 3 ≦ (N1 / N2) ≦ 5 is preferable. If the turn ratio is less than 3, improvement in the shutoff speed cannot be expected. As long as the electromagnet coil 3b of the circuit breaker 3 is not welded, the turn ratio can be 5 or more.

The operation of the electric device 100 including the breaker circuit transformer 4 will be described.
Since the circuit breaker 3 is a complete electromagnetic type in which the contact 3a is removed only by the action of an electromagnet, the circuit breaker 3 takes one of a non-operation state, a time-delay operation state, and an instantaneous operation state. In the non-operating state, the current of the circuit (sub circuit 6 in the first to third embodiments) is within the rated value, the electromagnet does not operate, and the circuit (main circuit 5 in the first to third embodiments) It is in a closed state. In the time delay operation state, when an overcurrent continues to flow in the circuit (sub circuit 6 in the first to third embodiments), the circuit (first to In the third embodiment, the main circuit 5) is shut off. In the instantaneous operation state, when a large current of a certain value or more flows in the circuit (sub circuit 6 in the first to third embodiments), the electromagnet is instantaneously connected to the circuit (first to third embodiments) due to an increase in leakage flux. In this state, the main circuit 5) is shut off.

In this electrical device 100, the primary coil 4a of the breaker circuit transformer 4 is inserted into the main circuit 5, and the secondary coil 4b is connected to the electromagnet coil 3b of the circuit breaker 3. Since the main circuit 5 and the sub circuit 6 are DC circuits, when the electrical equipment is operating normally, no current flows through the sub circuit 6 including the secondary coil 4b, and the circuit breaker 3 is in an inoperative state. is there.

When a short circuit occurs in the main circuit 5, a large amount of electric power corresponding to a current change due to the short circuit is supplied to the electromagnet coil 3 b of the circuit breaker 3 through the circuit breaker transformer 4. At that time, the current value caused by the short circuit generated in the primary coil 4a is further increased by supplying current to the electromagnet coil 3b by changing the current in the transformer 4 for the breaking circuit. Thereby, it will be in an instantaneous operation state, without passing through a time delay operation state. For this reason, the main circuit 5 can be interrupted by operating the circuit breaker 3 instantaneously when an overcurrent such as a short circuit occurs. As a result, the influence of the inrush current on various devices on the primary side main circuit can be suppressed low.

A specific configuration of the breaking circuit transformer 4 will be described below.
FIG. 2 is a diagram illustrating a schematic configuration of the first embodiment of the transformer for the cutoff circuit. The cutoff circuit transformer 4A is a cored transformer and has a rectangular annular core 10. The core 10 is made of a magnetic material such as an iron core. A primary coil 4a and a secondary coil 4b are wound around

portions

10a and 10b of the annular core 2 facing each other. The ratio (N1 / N2) of the number of turns of the primary coil 4a to the number of turns of the secondary coil 4b is, for example, 3 or more. When the turn ratio (N1 / N2) is 3, in other words, the turn ratio of the secondary coil 4b to the primary coil 4a is 1/3. If there are no restrictions on the physique, an air core can be used. When making it cored, it is necessary to make it the core physique which can accumulate | store the energy more than the interruption | blocking capacity | capacitance of the circuit breaker 3.

FIG. 3 is a diagram showing a schematic configuration of the second embodiment of the transformer for the cutoff circuit. This configuration of the cutoff circuit transformer 4B is effective when the size of the core 10 is small. In the breaking circuit transformer 4B, in addition to the configuration of the breaking circuit transformer 4A according to the first embodiment, a capacitor 11 is provided in parallel with the secondary coil 4b. Thereby, the secondary coil 4b is a resonance coil that resonates with the leakage magnetic flux of the primary coil 4a. In this case, the resonance frequency of the secondary coil 4b is preferably at least 250 Hz and 2.5 MHz or less. That is, preferably, the capacitor 11 is selected so as to satisfy this frequency condition. If the resonance frequency is within the above range, the cutoff time is 1 msec to 1 μsec.

Thus, if the secondary coil 4b is a resonance coil, even if the core 10 can only store energy equal to or less than the breaking capacity of the circuit breaker 3, the leakage flux of the primary coil 4a and the secondary coil 4b resonate. Thus, the magnetic saturation of the core 10 can be eliminated.

FIG. 4 is a diagram showing a schematic configuration of the third embodiment of the transformer for the cutoff circuit. This cutoff circuit transformer 4C is also a cored transformer. The core 10 has a middle leg portion 10c in the center of a rectangular ring. The core 10 also includes first and second

outer leg portions

10d and 10e each having two sides of the rectangle located on both sides of the middle leg portion 10c. The configuration of the cutoff circuit transformer 4C is also effective in suppressing the magnetic saturation of the core 10. A first magnetic circuit 12 and a second magnetic circuit 13 are formed in parallel with each other in the core 10 of the cutoff circuit transformer 4C. A part of the first magnetic circuit 12 is configured in the first outer leg part 10d, and a part of the second magnetic circuit 13 is configured in the second outer leg part 10e. A primary coil 4 a and a secondary coil 4 b are wound around a middle leg portion 10 c that is a shared part of the first magnetic circuit 12 and the second magnetic circuit 13.

The first magnetic circuit 12 is a circuit serving as a path for magnetic flux generated when a current flows through the primary coil 4a. As in the illustrated example, it is preferable that an air gap 14 is provided in a portion of the first magnetic circuit 12 that is not shared with the second magnetic circuit 13 (first outer leg portion 10d). The middle leg portion 10c and the

outer leg portions

10d and 10e may have the same cross-sectional area.

A permanent magnet 15 is provided in the second outer leg portion 10e in which a part of the second magnetic circuit 13 is configured. The permanent magnet 15 applies a magnetic flux 17 that is a reverse bias with respect to the magnetic flux 16 that passes through the first magnetic circuit 12. A non-magnetic and conductive demagnetization preventing member 18 is installed on the outer periphery of the permanent magnet 15 to prevent demagnetization. In addition, it is preferable that the middle leg part 10 c is disposed at a position close to the permanent magnet 15.

By adjusting the size of the air gap 14 and the length of the permanent magnet 15, the reluctance of the second magnetic circuit 13 is reduced in the first magnetic circuit 12 with respect to the magnetic flux generated by the current flowing through the primary coil 4 a. It is set larger than the magnetic resistance. As a result, the magnetic flux generated by the current flowing through the primary coil 4a flows preferentially to the first magnetic circuit 12 side having a low magnetic resistance, so that the magnetic flux indicated by reference numeral 16 is generated.

Also, with respect to the magnetic flux generated by the permanent magnet 15, the middle leg portion 10c has a smaller magnetic resistance than the first outer leg portion 10d provided with the air gap 14. For this reason, when the magnetic flux by the permanent magnet 15 flows preferentially to the part 10d of the core 10, the flow of the magnetic flux indicated by reference numeral 17 occurs, and a reverse bias can be effectively applied.

With this configuration, the magnetic flux 17 that is reverse-biased by the permanent magnet 15 provided in the second magnetic circuit 13 is applied to the magnetic flux 16 that passes through the first magnetic circuit 12. As a result, the magnetic flux 16 flowing through the first magnetic circuit 12 and the magnetic flux 17 flowing through the second magnetic circuit 13 cancel each other, and the magnetic flux density of the core 10 is reduced. For this reason, normally, only the first quadrant portion on the BH curve (magnetic hysteresis curve: see FIG. 5) can be used from the third quadrant portion. As a result, even the core 10 having a small physique is not easily magnetically saturated.

When the air gap 14 is provided in a portion (first outer leg portion 10d) that is not shared with the second magnetic circuit 13 in the first magnetic circuit 12, the magnetic flux 17 generated by the permanent magnet 15 is generated by the first magnetic circuit. 12 and the second magnetic circuit 13 are easily passed through a shared portion (middle leg portion 10c). In addition, the magnetic flux 17 generated by the permanent magnet 15 is also generated when the shared portion (the middle leg portion 10 c) of the first magnetic circuit 12 and the second magnetic circuit 13 is disposed near the permanent magnet 15. The magnetic circuit 12 and the second magnetic circuit 13 can easily pass through the shared portion (the middle leg portion 10c). As described above, when the magnetic flux 17 generated by the permanent magnet 15 easily passes through the shared portion of the first magnetic circuit 12 and the second magnetic circuit 13, the magnetic flux 17 generated by the permanent magnet 15 acts efficiently as a reverse bias.

If the air gap 14 is not provided, as shown in FIG. 6, the magnetic flux 17 generated by the permanent magnet 15 causes the shared portion (the middle leg portion 10c) of the first magnetic circuit 12 and the second magnetic circuit 13 to be present. Without passing, there is a possibility that the first magnetic circuit 12 may pass through a portion not shared with the second magnetic circuit 13 (first outer leg portion 10d). In this case, the reverse bias action of the magnetic flux 17 generated by the permanent magnet 15 is reduced. Providing the air gap 14 prevents such a situation from occurring.

A configuration in which the secondary coil 4b is a resonance coil (FIG. 3) and a configuration in which a permanent magnet 15 for reverse excitation is provided (FIG. 4) can be used in combination.

As mentioned above, although the form for implementing this invention based on the Example was demonstrated, embodiment disclosed here is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 3 ... Circuit breaker 3a ... Contact 3b ...

Electromagnetic coils

4, 4A, 4B, 4C ... Breaking circuit transformer 4a ... Primary coil 4b ... Secondary coil 5 ... Main circuit 6 ... Sub circuit

Claims

A primary coil provided by being connected in series or in parallel with the contact in a main circuit composed of a DC circuit provided with the contact of the circuit breaker for opening and closing the contact with an electromagnet;
A secondary circuit provided in series with the electromagnet coil in a sub-circuit provided with an electromagnet coil for exciting the electromagnet of the circuit breaker;
A circuit breaker transformer in which a turn ratio of the primary coil and the secondary coil is set so that a current value flowing through the secondary coil is larger than a current value flowing through the primary coil.
The transformer for a cutoff circuit according to claim 1, wherein the transformer for the cutoff circuit is a cored transformer, and the secondary coil is a resonance coil that resonates with a leakage flux of the primary coil. Transformer for circuit breaker that is provided with a capacitor in series or in parallel.
3. The circuit breaker transformer according to claim 1, further comprising: a core around which the primary coil and the secondary coil are wound, and the core generates a magnetic flux generated by a current flowing through the primary coil. A first magnetic circuit and a second magnetic circuit in parallel with the first magnetic circuit are formed, and occurs when an inrush current flows through the primary coil in the second magnetic circuit. A circuit breaker transformer provided with a permanent magnet that applies a magnetic flux that is reversely biased with respect to the magnetic flux to be applied.
4. The circuit breaker transformer according to claim 3, wherein an air gap is provided at a location where the primary coil and the secondary coil of the core portion constituting the first magnetic circuit are not wound.
4. The circuit breaker transformer according to claim 1, wherein the transformer is a cored transformer having a turn ratio of the secondary coil to the primary coil of 1/3 or less. 5. A breaker circuit transformer having a capacity capable of storing energy equal to or greater than a breaker capacity of the circuit breaker.
A circuit breaker having a contact provided in a main circuit composed of a DC circuit, an electromagnet for opening and closing the contact, and a coil for an electromagnet provided in a sub-circuit for exciting the electromagnet;
A primary coil provided in the main circuit connected in series or in parallel with the contact; and a circuit breaker transformer having a secondary coil connected in series with the electromagnet coil and provided in the sub circuit. Circuit breaker,
A circuit breaker in which a turn ratio of the primary coil and the secondary coil is set so that a current value flowing through the secondary coil is larger than a current value flowing through the primary coil.
7. The circuit breaker according to claim 6, wherein the breaker circuit transformer is a cored transformer, and is connected in series with the secondary coil to the breaker circuit transformer so as to be a resonance coil that resonates with the leakage flux of the primary coil. Or a circuit breaker provided with a capacitor in parallel.
The circuit breaker according to claim 6 or 7, wherein the breaker circuit transformer has a core around which the primary coil and the secondary coil are wound, and the core is configured to allow a current of the primary coil to flow. And a second magnetic circuit in parallel with the first magnetic circuit, and an inrush current to the primary coil is formed in the second magnetic circuit. The circuit breaker provided with the permanent magnet which applies the magnetic flux which becomes a reverse bias with respect to the magnetic flux which generate | occur | produces when an electric current flows.
9. The circuit breaker according to claim 8, wherein an air gap is provided at a location where the primary coil and the secondary coil of the core portion constituting the first magnetic circuit are not wound.
10. The circuit breaker according to claim 6, wherein the breaker circuit transformer is a cored transformer having a turn ratio of the secondary coil to the primary coil of 1/3 or less. The circuit breaker having a capacity at which the core of the cored transformer has a capacity capable of storing energy equal to or greater than the breaking capacity of the circuit breaker.
An electrical device provided with the circuit breaker according to any one of claims 6 to 10.
The electric device according to claim 11, wherein the electric device is a quick charger for an electric vehicle.