KR102194893B1 - Drive circuit for blow-out coil and DC circuit breaker using the same - Google Patents

Abstract

The present invention relates to a drive circuit for a blow-out coil and a DC circuit breaker using the same. According to an embodiment of the present invention, the drive circuit for the blow-out coil is the drive circuit which drives a magnetic extinguishing coil to extinguish an arc at an electrical contact using magnetic flux. The drive circuit includes: a DC power supply unit; a charging unit for charging power supplied from the DC power supply unit; and a switching unit performing first switching so that the power of the DC power supply is supplied to the charging unit, second switching so that the power charged in the charging unit is supplied to the blow-out coil in the first direction, or third switching so that the power charged in the charging unit is supplied to the blow-out coil in the second direction, thereby reducing power loss that occurs when driving the blow-out coil.

Description

Drive circuit for blow-out coil and DC circuit breaker using the same}

The present invention relates to a driving circuit of a magnetic extinguishing coil and a DC circuit breaker having the same, and more particularly, a driving circuit of a magnetic extinguishing coil capable of driving a pulsed excitation current for a magnetic extinguishing coil used for arc extinguishing, and It relates to a DC circuit breaker having this.

1 shows a graph of the current over time in AC power and DC power, and FIG. 2 is an arc current generated at an electrical contact when DC is cut off using a DC breaker such as an air circuit breaker (ACB or ACCB). I _ARC ).

Referring to FIG. 1, in the case of an AC power source, a current zero point occurs at which the current becomes zero (0) every half cycle. Accordingly, when an abnormal current (hereinafter referred to as “accident current”) occurs in an AC system, it is relatively easy to block the corresponding fault current.

On the other hand, the DC power supply does not generate a current zero point, unlike AC power, since current continuously flows at a constant level. Accordingly, in the direct current system, as shown in FIG. 2, when the current is cut off, arc current (I _ARC ) is easily generated, and life and property due to burnout of facilities and electric fire due to strong arc current (I _ARC ) There is a high possibility of loss

Therefore, when a fault current occurs in the DC system, the fault current does not generate a current zero point, so when the current is cut off, the arc current (I _ARC ) generated at the contact point is extinguished using a magnetic flux (magnetic line). DC circuit breaker has been developed and used.

3 shows the principle of the magnetic arc extinguishing method.

Referring to FIG. 3(a), in the magnetic arc extinguishing method, the magnet is disposed so that the direction of the magnetic flux formed in the magnet M is perpendicular to the flow direction of the arc current I _ARC generated at the electrical contact. As a result, as shown in Fig. 3(b), according to Fleming's left-hand rule, a Lorentz force is applied to the arc current and the arc is dispersed into space, and the arc resistance value increases accordingly. As a result, the arc energy is rapidly consumed and the arc is finally extinguished.

Fig. 4 shows a driving circuit of a conventional blow out coil using a magnetic arc extinguishing method.

Meanwhile, among the magnetic arc extinguishing methods, there is a method using an electromagnet instead of a permanent magnet. In this case, by changing the direction of the magnetic flux generated in the electromagnet according to the flow of the load current, magnetic arc extinguishing for the load current in both directions is possible. At this time, the used electromagnet is referred to as “magnetic extinguishing coil” (BC).

That is, referring to FIG. 4, the driving circuit of the conventional self-extinguishing coil BC (hereinafter referred to as “conventional technology”) changes the direction of the excitation voltage in the switch box SW provided with a plurality of switches, The blow-out coil BC may be excited in a first direction (forward direction) or in a second direction (reverse direction). Particularly, in order to effectively perform arc extinguishing, it is necessary to increase the effective magnetic flux density at an electric point contact where an arc is generated by increasing the magnetomagnetic force of the magnetic extinguishing coil BC. However, there is a problem that the driving circuit of the conventional self-extinguishing coil cannot satisfy these requirements.

In order to solve the problems of the prior art as described above, the present invention drives a pulsed excitation current with respect to the magnetic extinguishing coil used for arc extinguishing, thereby increasing the magnetomagnetic force of the magnetic extinguishing coil. An object thereof is to provide a driving circuit for a magnetic extinguishing coil capable of increasing the effective magnetic flux density and a DC circuit breaker using the same.

However, the problem to be solved by the present invention is not limited to the problems mentioned above, and other problems that are not mentioned will be clearly understood by those skilled in the art from the following description.

A driving circuit for a magnetic extinguishing coil according to an embodiment of the present invention for solving the above problems is a driving circuit for driving a magnetic extinguishing coil that extinguishes an arc at an electrical contact by using a magnetic flux, (1) a DC power supply unit, (2) a charging unit that charges the power supplied from the DC power supply unit, (3) the first switching so that the power of the DC power supply unit is supplied to the charging unit, or the second switching so that the power charged in the charging unit is supplied to the magnetic extinguishing coil in the first direction Alternatively, it includes a switching unit for third switching so that the power charged in the charging unit is supplied to the magnetic extinguishing coil in the second direction.

The switching unit performs the first switching and then performs a first operation of performing any one of the second switching and the third switching, and after performing the first switching, the second switching unit performs the other one of the second switching and the third switching. Can perform actions

The switching unit may alternately perform a first operation and a second operation.

The switching unit may include a first switch and a second switch.

The first switch is such that the C+ terminal connected to one end of the charging unit is connected to any one of the S+ terminal connected to the positive pole of the DC power supply, the P+ terminal connected to one end of the magnetic extinguishing coil, and the N+ terminal connected to the other end of the magnetic extinguishing coil. Can be switched.

The second switch has a C-terminal connected to the other end of the charging unit, an S-terminal connected to the negative pole of the DC power supply, a P-terminal connected to the other end of the magnetic extinguishing coil, and an N-terminal connected to one end of the self-extinguishing coil. You can switch to connect with one.

A driving circuit for a magnetic extinguishing coil according to an embodiment of the present invention includes: (1) a first rectifying element for passing a current in a first direction between the P+ terminal and one end of the magnetic extinguishing coil, and (2) the N+ terminal And a second rectifying element for passing a current in a second direction between the other end of the magnetic extinguishing coil.

When the C+ terminal is connected to the P+ terminal, the C-terminal may be connected to the P-terminal, and when the C+ terminal is connected to the N+ terminal, the C-terminal is the N-terminal. It may be connected to, and when the C+ terminal is connected to the S+ terminal, the C- terminal may be connected to the S- terminal.

A resistor connected between the positive electrode of the DC power supply unit and the S+ terminal or between the negative electrode of the DC power supply unit and the S- terminal may further include a resistor that limits the current supplied to the charging unit.

During the second switching and the third switching, it is possible to drive a pulsed excitation current according to a resonance phenomenon generated by a capacitance C of the charging unit and an inductance L of the self-extinguishing coil.

A DC circuit breaker according to an embodiment of the present invention prevents magnetic flux from an electrical contact connected between a DC power source and a load, a disconnect switch for switching whether or not the electrical contact is connected, and an arc at the electrical contact that occurs when the electrical contact is cut off. It is a DC circuit breaker each including a self-extinguishing coil to be extinguished using and a driving circuit for driving the self-extinguishing coil.

The driving circuit may include (1) a DC power supply unit, (2) a charging unit that charges power supplied from the DC power supply unit, (3) a first switching so that power from the DC power supply unit is supplied to the charging unit, or the power charged to the charging unit is self-extinguishing. It may include a switching unit for second switching to be supplied to the coil in a first direction, or a switching unit for third switching so that power charged in the charging unit is supplied to the self-extinguishing coil in a second direction.

A DC circuit breaker according to an embodiment of the present invention includes: (1) a core inserted into the magnetic extinguishing coil, (2) a magnetic pole connected to the core so that the magnetic flux generated from the magnetic extinguishing coil acts toward an electrical contact. It may include more pieces.

The pole piece may be formed in a plate shape.

The present invention configured as described above can drive a pulsed excitation current for a magnetic extinguishing coil used for arc extinguishing, thereby increasing the magnetic force of the magnetic extinguishing coil, thereby increasing the effective magnetic flux density at the electrical contact point where an arc is generated. In addition, there is an effect of reducing the power loss generated when driving the blowout coil and increasing the self-extinguishing power at the same time.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned can be clearly understood by those of ordinary skill in the art from the following description. will be.

1 shows a graph of current over time in AC power and DC power.
Figure 2 shows the arc current (I _ARC ) generated at the electrical contact when DC is cut off using a DC circuit breaker such as an air circuit breaker (ACB or ACCB).
3 shows the principle of the magnetic arc extinguishing method.
Fig. 4 shows a driving circuit of a conventional blow out coil using a magnetic arc extinguishing method.
5 shows a schematic configuration diagram of a DC circuit breaker 1000 according to an embodiment of the present invention.
6 shows a configuration diagram of a driving circuit 400 according to an embodiment of the present invention.
7 shows various switching operations performed by the switching unit 430 of the driving circuit 400 according to an embodiment of the present invention.
8 is a graph showing a comparison between the results of the driving circuit 400 according to an embodiment of the present invention and the excitation current (I _coil ) generated according to the conventional excitation method.

The above objects and means of the present invention, and effects thereof, will become more apparent through the following detailed description in connection with the accompanying drawings, and accordingly, a person having ordinary knowledge in the technical field to which the present invention belongs can facilitate the technical idea of the present invention. It will be possible to do it. In addition, in describing the present invention, when it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted.

The terms used in this specification are for describing exemplary embodiments, and are not intended to limit the present invention. In the present specification, the singular form also includes the plural form in some cases, unless specifically stated in the phrase. In the present specification, terms such as "include", "include", "provision" or "have" do not exclude the presence or addition of one or more other elements other than the mentioned elements.

In the present specification, terms such as “or” and “at least one” may represent one of words listed together, or a combination of two or more. For example, “or B” “at least one of “and B” may include only one of A or B, and may include both A and B.

In this specification, the description following “for example” may not exactly match the information presented, such as the recited characteristics, variables, or values, and tolerances, measurement errors, limitations of measurement accuracy, and other commonly known factors. It should not be limited to the embodiments of the invention according to the various embodiments of the present invention to effects such as modifications including.

In the present specification, when a component is described as being'connected' or'connected' to another component, it may be directly connected or connected to the other component, but other components exist in the middle. It should be understood that it may be possible. On the other hand, when a component is referred to as being'directly connected' or'directly connected' to another component, it should be understood that there is no other component in the middle.

In the present specification, when a component is described as being'on' or'adjacent' of another component, it may be directly in contact with or connected to another component, but another component exists in the middle. It should be understood that it is possible. On the other hand, when a component is described as being'directly above' or'directly' of another component, it may be understood that there is no other component in the middle. Other expressions describing the relationship between components, for example,'between' and'directly,' can be interpreted as well.

In this specification, terms such as'first' and'second' may be used to describe various elements, but the corresponding elements should not be limited by the above terms. In addition, the terms above should not be interpreted as limiting the order of each component, and may be used for the purpose of distinguishing one component from another component. For example, the'first element' may be named'second element', and similarly, the'second element' may also be named'first element'.

Unless otherwise defined, all terms used in the present specification may be used as meanings that can be commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not interpreted ideally or excessively unless explicitly defined specifically.

Hereinafter, a preferred embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

5 shows a schematic configuration diagram of a DC circuit breaker 1000 according to an embodiment of the present invention.

The DC circuit breaker 1000 according to an embodiment of the present invention is a device that cuts off DC power (V _DC ) supplied to a DC system when an accident current occurs. Referring to FIG. 5, the DC circuit breaker 1000 according to an embodiment of the present invention switches whether or not the electrical contact 100 receiving power from a DC power supply (V _DC ) and the electrical contact 100 are connected ( Switching the cut-off switch 200 and a blow out coil that extinguishes the arc at the electrical contact 100 that occurs when the electrical contact 100 is cut off using a magnetic flux (magnetic line of force) ( 300) and a driving circuit 400 for driving the self-extinguishing coil 300, and the like.

In addition, the DC circuit breaker 1000 according to an embodiment of the present invention includes a core 500 inserted into the magnetic extinguishing coil 300 and connected to the core 500 so that the magnetic extinguishing coil 300 The generated magnetic flux acts on or around the electrical contact 100, but may further include a pole face 600 disposed to act at a right angle to the direction of the arc current.

At this time, the core 500 and the pole piece 600 may be made of a metal material, and two pairs may be provided. In this case, each pole piece 600 may be formed in a plate shape, and may be spaced apart from each other and disposed to face each other. Accordingly, the core 500 may further enhance the magnetic flux generated in the magnetic extinguishing coil 300, and each magnetic pole piece 600 transmits the generated magnetic flux to the electrical contact 100 disposed in the spaced space or around it. By acting, magnetic extinguishing of the arc at the electrical contact 100 can be performed.

However, in FIG. 5, only a pair of cores 500 and pole pieces 600 are shown to be placed on the magnetic extinguishing coil 300, but the present invention is not limited thereto, and other pairs of cores 500 and poles The self-extinguishing coil 300 and its driving circuit 400 may be disposed on the piece 600 as well.

The magnetic extinguishing coil 300 is an electromagnet in the form of a coil for extinguishing a magnetic arc, and forms a magnetic flux when current is supplied, but forms a magnetic flux direction differently according to the direction of the supplied current. That is, the magnetic extinguishing coil 300 forms a magnetic flux in a direction according to the Ampere's right hand screw rule. In particular, for the application of the magnetic arc extinguishing method, the magnetic extinguishing coil 300 is disposed around the electrical contact 100 so that the direction of the magnetic flux is perpendicular to the flow direction of the arc current generated from the electrical contact 100. I can.

6 shows a configuration diagram of a driving circuit 400 according to an embodiment of the present invention, and FIG. 7 is a variety of switching operations performed by the switching unit 430 of the driving circuit 400 according to an embodiment of the present invention. Represents.

The driving circuit 400 according to an embodiment of the present invention is a circuit for driving the self-extinguishing coil 3000, and as shown in FIG. 6, a DC power supply unit 410, a charging unit 420, a switching unit 430, and A switching control unit 440 may be included.

The DC power supply unit 410 is configured to supply a DC power supply (V _supply ). For example, the DC power supply unit 410 may supply high voltage DC such as 1,500 [V].

The charging unit 420 is configured to charge the power V _suuply according to the DC current I _charge supplied from the DC power supply unit 420. For example, the charging unit 420 may include one or more capacitors or capacitor banks.

The switching unit 430 is a component capable of switching to 2 poles 3. Referring to FIG. 7, the switching unit 430 switches so that a direct current (I _charge ) according to the power of the DC power supply unit 410 is supplied to the charging unit 420 (hereinafter referred to as “first switching”) (FIG. 7 (a) Reference) or switching so that the current (I _coil1 ) according to the power charged in the charging unit 410 is supplied to the self-extinguishing coil 300 in the first direction (forward direction) (hereinafter referred to as “second switching”) ) (Refer to Fig. 7(b)) or switching so that the current (I _coil2 ) according to the power charged in the charging unit 420 is supplied to the self-extinguishing coil 300 in the second direction (reverse direction) (hereinafter, “third Switching”) (refer to Fig. 7(c)).

Specifically, the switching unit 430 includes a first switch 431 and a second switch 432 respectively switching one of the three furnaces, that is, one of the three terminals to be connected to the C+ terminal or the C- terminal, respectively. I can.

That is, the first switch 431 switches the C+ terminal connected to one end of the charging unit 420 to be connected to any one of the S+ terminal, the P+ terminal, and the N+ terminal. At this time, the S+ terminal may be connected to the anode of the DC power supply unit 410, the P+ terminal may be connected to one end of the self-extinguishing coil 300, and the N+ terminal may be connected to the other end of the self-extinguishing coil 300.

In addition, the second switch 432 switches so that the C-terminal connected to the other end of the charging unit 4200 is connected to one of the S-terminal, P-terminal, and N-terminal. At this time, the S-terminal is a DC power supply unit. It may be connected to the cathode of 410, the P-terminal may be connected to the other end of the magnetic extinguishing coil 300, and the N-terminal may be connected to one end of the magnetic extinguishing coil 300.

The S+ terminal and the S- terminal are terminals arranged for the first switching. In the first switching, the S+ terminal is connected to the C+ terminal and the S- terminal is connected to the C- terminal, respectively. The P+ terminal and the P- terminal are arranged for the second switching. In the second switching, the P+ terminal is connected to the C+ terminal and the P- terminal is connected to the C- terminal, respectively. In addition, the N+ terminal and the N- terminal are arranged for the third switching, and in the third switching, the N+ terminal is connected to the C+ terminal and the N- terminal is connected to the C- terminal, respectively.

That is, in the switching unit 430, the switching unit 430 is the second switch 432 so that the C-terminal and the S-terminal are connected when the first switch 431 is operated so that the C+ terminal and the S+ terminal are connected. The first switching can be performed by operating. In addition, when the first switch 431 operates so that the C+ terminal and the P+ terminal are connected, the second switch 432 operates so that the C- terminal and the P- terminal are connected, thereby performing the second switching. Similarly, when the first switch 431 is operated to be connected to the C+ terminal and the N+ terminal, the third switching may be performed by operating the second switch 432 to connect the C- and N-terminals.

Meanwhile, the switching unit 400 performs a first operation of performing any one of the second switching and the third switching after performing the first switching, and the other of the second switching and the third switching after performing the first switching. A second operation of performing may be performed. In particular, the switching unit 400 may alternately perform the first operation and the second operation.

Meanwhile, the driving circuit 400 according to an embodiment of the present invention further includes a first rectifying element 450 and a second rectifying element 460 for blocking current in the opposite direction during the second switching and the third switching. can do. That is, the first rectifying element 450 passes the current I _coil1 in the first direction between the P+ terminal and one end of the self-extinguishing coil 300 but blocks the current I _{coil2 in} the second direction. Likewise, the second rectifying element 460 passes a current I _coil2 in the second direction between the N+ terminal and the other end of the self-extinguishing coil 300 but blocks the current I _{coil1 in} the first direction.

In addition, the driving circuit 400 according to an embodiment of the present invention may further include a resistor 470 that limits the current I _charge supplied to the charging unit 420. That is, the resistor 470 may adjust the magnitude of the current I _charge to match the capacity of the charging unit 420. That is, the charging current I _charge flowing through the charging unit 420 is limited by the resistor 470 and flows. In this case, the resistor 470 may be connected in series between the positive electrode and the S+ terminal of the DC power supply unit 410 or between the negative electrode and the S- terminal of the DC power supply unit 410.

8 is a graph showing a comparison between the results of the driving circuit 400 according to an embodiment of the present invention and the excitation current (I _coil ) generated according to the conventional excitation method.

Referring to FIG. 8, the prior art according to FIG. 4 generates an excitation current (I _coil ) having a relatively small size while being in a DC excitation. On the other hand, the driving circuit 400 according to an embodiment of the present invention is generated by the capacitance (C) of the charging unit 420 and the inductance (L) of the self-extinguishing coil 300 during the second and third switching. According to the LC resonance phenomenon, it is possible to drive a pulse type (pluse excitation) but a relatively large excitation current (I _coil ) for a short period of time (for example, 100 [ms] or less). Accordingly, the present invention can increase the magnetomagnetic force of the magnetic extinguishing coil 300, thereby increasing the effective magnetic flux density in the electrical contact point 100 where an arc is generated.

That is, the driving circuit 400 according to an embodiment of the present invention can drive a pulsed excitation current by resonance for a short period of time instead of continuously driving an excitation current, thereby driving an excitation current that is tens of times larger than that of the prior art. And, accordingly, it is possible to generate a larger magnetic flux in the pole piece 600. As a result, since the driving circuit 400 according to an embodiment of the present invention generates a larger magnetic flux than the prior art even when the same power is supplied, the power loss generated when the blow-out coil 300 is driven is reduced while at the same time self-extinguishing power. Can increase.

Meanwhile, the switching control unit 440 is a component that controls the switching operation of the switching unit 430. For example, the switching control unit 440 may be configured with a control relay or the like.

The switching control unit 440 charges the charging unit 420 by controlling the switching unit 430 to first switch during normal operation. Thereafter, when a cut-off command is generated according to an accident current or the like, the switching control unit 440 controls the switching unit 430 to perform the second switching or the third switching according to the flow direction of the load current.

That is, when the load current is in the first direction at the moment when the cut-off command is generated, the switching control unit 440 controls the switching unit 430 to switch the second so that the self-extinguishing coil 300 has a half cycle pulse in the first direction. The type excitation current is applied. After the half cycle, when the reverse current is about to flow according to the LC resonance, the excitation current is blocked by the first rectifying element 450 and no longer flows, and the excitation of the self-extinguishing coil 300 is terminated. When the blocking is complete, the switching control unit 440 controls the switching unit 430 to first switch to recharge the charging unit 420.

On the other hand, when the load current is in the second direction at the moment when the cut-off command is generated, the switching control unit 440 controls the switching unit 430 to switch the third, so that the self-extinguishing coil 300 has a half cycle pulse according to the second direction. Apply excitation current. After a half cycle, when the reverse current is about to flow according to the LC resonance, the excitation current is blocked by the second rectifying element 460 and no longer flows, and the excitation of the self-extinguishing coil 300 is terminated. When the blocking is complete, the switching control unit 440 controls the switching unit 430 to first switch to recharge the charging unit 420.

A specific example of designing the driving circuit 400 according to an embodiment of the present invention is as follows.

First, a relatively large 1500[V] main voltage (V _supply ) is used to secure a sufficiently large excitation current. Assuming that the operation delay time T _delay of the switching control unit 440 is 5 [ms], the excitation target can be set as follows.

_-Excitation time (T _excite ): 50[㎳]

_-Excitation peak current (I _peak ): 100[A]

According to the LC resonance theory, the following conditions are established between the capacitance C of the charging unit 420 and the inductance L _coil of the self-extinguishing coil 300.

(1)

(One)

(2)

(2)

Accordingly, the capacitance C of the charging unit 420 and the inductance L _coil of the self-extinguishing coil 300 may be calculated as follows.

(3)

(3)

(4)

(4)

(5)

(5)

In the detailed description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the present invention is not limited to the described embodiments, and should be defined by the claims to be described later and equivalents to the claims.

100: electrical contact 200: disconnect switch
300, BC: magnetic extinguishing coil 400: driving circuit
410: DC power supply unit 420: charging unit
430: switching unit 431: first switch
432: second switch 440: switching control unit
450: first rectifying element 460: second rectifying element
500, CO: core 600, MP: pole piece
1000: DC circuit breaker SW: switch box

Claims (11)

As a driving circuit that drives a magnetic extinguishing coil that extinguishes the arc generated when the electrical contact connected between the DC power supply and the load is cut off using magnetic flux,
DC power supply;
A charging unit including a capacitor for charging power supplied from the DC power supply unit; And
Switch the first so that power from the DC power supply is supplied to the charging unit, or switch the second so that the power charged in the charging unit is supplied to the magnetic extinguishing coil in the first direction, or the power charged in the charging unit is supplied to the magnetic extinguishing coil in the second direction Includes; a switching unit for switching the third so as to be,
The switching unit,
A first switch for switching so that the C+ terminal connected to one end of the charging part is connected to any one of the S+ terminal connected to the positive pole of the DC power supply, the P+ terminal connected to one end of the magnetic extinguishing coil, and the N+ terminal connected to the other end of the magnetic extinguishing coil. ; And
Switching so that the C-terminal connected to the other end of the charging part is connected to one of the S-terminal connected to the negative pole of the DC power supply, the P-terminal connected to the other end of the magnetic extinguishing coil, and the N-terminal connected to one end of the magnetic extinguishing coil. Each includes a second switch;
Performing a first operation of performing any one of the second switching and the third switching after performing the first switching, and performing a second operation of performing the other of the second switching and the third switching after performing the first switching And
The first switch is operated so that the C+ terminal and the S+ terminal are connected by performing the first switching during normal operation, and the second switch is operated so that the C- terminal and the S- terminal are connected,
When the load current is in the first direction when the cut-off command is generated, the first switch is operated so that the C+ terminal and the P+ terminal are connected, and the C- terminal and the P- terminal are connected by performing the second switching. The second switch operates,
When the load current is in the second direction when the cut-off command is generated, the first switch is operated to be connected to the C+ terminal and the N+ terminal by performing the third switching, and the C- terminal and the N- terminal are connected. The second switch operates,
At the time of the second switching and the third switching according to the occurrence of a blocking command, a pulse-type excitation current according to LC resonance generated by the capacitance (C) of the capacitor and the inductance (L) of the self-extinguishing coil is driven for a half cycle, and , A driving circuit of a magnetic extinguishing coil, characterized in that the reverse excitation current of the LC resonance is blocked by a rectifying element after a half cycle.
delete The method of claim 1,
The driving circuit of the magnetic extinguishing coil, characterized in that the switching unit alternately performs a first operation and a second operation.
delete The method of claim 1,
A first rectifying element for passing a current in a first direction between the P+ terminal and one end of the magnetic extinguishing coil; And
A second rectifying element for passing a current in a second direction between the N+ terminal and the other end of the magnetic extinguishing coil;
A driving circuit of a magnetic extinguishing coil, characterized in that it further comprises.
delete The method of claim 1,
The driving circuit of the magnetic extinguishing coil, characterized in that it further comprises a resistor connected between the positive pole of the DC power supply and the S+ terminal or between the negative pole and the S- terminal of the DC power supply and limiting the current supplied to the charging unit. .
delete The electrical contact connected between the DC power supply and the load, a disconnect switch that switches whether or not the electrical contact is connected, a magnetic extinguishing coil that extinguishes the arc at the electrical contact that occurs when the electrical contact is disconnected using magnetic flux, and a magnetic extinguishing coil As a DC circuit breaker each comprising a driving circuit for driving,
The driving circuit,
DC power supply;
A charging unit including a capacitor for charging power supplied from the DC power supply unit; And
Switch the first so that power from the DC power supply is supplied to the charging unit, or switch the second so that the power charged in the charging unit is supplied to the magnetic extinguishing coil in the first direction, or the power charged in the charging unit is supplied to the magnetic extinguishing coil in the second direction Includes; a switching unit for switching the third so as to be,
The switching unit,
A first switch for switching so that the C+ terminal connected to one end of the charging part is connected to any one of the S+ terminal connected to the positive pole of the DC power supply, the P+ terminal connected to one end of the magnetic extinguishing coil, and the N+ terminal connected to the other end of the magnetic extinguishing coil. ; And
Switching so that the C-terminal connected to the other end of the charging part is connected to one of the S-terminal connected to the negative pole of the DC power supply, the P-terminal connected to the other end of the magnetic extinguishing coil, and the N-terminal connected to one end of the magnetic extinguishing coil. Each includes a second switch;
Performing a first operation of performing any one of the second switching and the third switching after performing the first switching, and performing a second operation of performing the other of the second switching and the third switching after performing the first switching And
The first switch is operated so that the C+ terminal and the S+ terminal are connected by performing the first switching during normal operation, and the second switch is operated so that the C- terminal and the S- terminal are connected,
When the load current is in the first direction when the cut-off command is generated, the first switch is operated so that the C+ terminal and the P+ terminal are connected, and the C- terminal and the P- terminal are connected by performing the second switching. The second switch operates,
When the load current is in the second direction when the cut-off command is generated, the first switch is operated to be connected to the C+ terminal and the N+ terminal by performing the third switching, and the C- terminal and the N- terminal are connected. The second switch operates,
During the second switching and the third switching according to the occurrence of a blocking command, a pulsed excitation current according to LC resonance generated by the capacitance (C) of the capacitor and the inductance (L) of the self-extinguishing coil is driven for a half cycle, and , DC circuit breaker, characterized in that the reverse excitation current of LC resonance is blocked by using a rectifying element after a half cycle.
The method of claim 9,
A core inserted into the magnetic extinguishing coil; And
A magnetic pole piece connected to the core so that the magnetic flux generated from the magnetic extinguishing coil acts toward an electrical contact;
DC circuit breaker, characterized in that it further comprises.
The method of claim 10,
The pole piece is a DC circuit breaker, characterized in that formed in a plate shape.

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