JP5649231B2 - High frequency reactor - Google Patents

Description

  The present invention relates to a high-frequency reactor, and more particularly to a high-frequency reactor in which a large current of several hundreds A or more flows at a high frequency of several kHz to several hundred kHz. This high frequency reactor can be suitably used for a power conversion circuit or a resonance circuit.

  Conventionally, air-core solenoid coils have been generally used in high-frequency reactors used for high-frequency and high-current applications such as power converter circuits and resonant circuits. However, when an air-core solenoid coil is used, the leakage magnetic flux increases, so it is necessary to prevent the surrounding metal structure from being overheated by induction heating. Therefore, a measure to suppress heat generation by placing the air-core solenoid coil away from the surrounding metal structure can be considered, but in this case, the high frequency reactor occupies a large space (enlarges). turn into. In addition, there is a measure of covering with a copper water-cooled magnetic shielding plate, but doing so complicates the structure of the high-frequency reactor and increases the manufacturing cost.

  In order to eliminate the difficulty of such an air core solenoid coil, in recent years, a core (iron core) made of a ferromagnetic material has been used as a member for forming a magnetic path. Reactors that use the core as a magnetic path forming member have been used in the past for DC and low frequencies, but when applied to high-frequency and high-current applications, as described below, solve the problem of cooling the core. There is a need to.

  That is, an AC reactor using the core as a magnetic path forming member requires a gap that becomes a magnetic resistance in the core in order to obtain a desired inductance. However, if a single gap is used, the gap becomes large and the leakage flux becomes excessive.In general, a large number of small gaps are provided at intervals in the core, thereby ensuring the required gap amount as a whole. ing. These small gaps are usually filled with a molding of an insulating material.

  In this type of AC reactor, since the thermal conductivity of the insulating material filled in the small gap is low, individual portions of the core divided (sandwiched) by the small gap (insulating material) are difficult to be cooled. As a result, these parts generate heat due to iron loss, and the core may be overheated. Therefore, it is necessary to cool the core by some method, and the following has been proposed as a countermeasure.

  In Patent Document 1, a cooling pipe is provided in parallel with the magnetic path of the core, a filler having a good thermal conductivity is disposed between the cooling pipe and the core, and the coolant is caused to flow through the cooling pipe. To cool down. As the cooling pipe, a hollow copper pipe having good thermal conductivity is cited.

  In Patent Document 2, a main iron core leg configured by stacking a plurality of iron core (core) blocks via a gap material (gap part), a yoke disposed at both ends of the main iron core leg, and those A fastening plate disposed outside the yoke, and a main iron core leg, and a fastening connecting member inserted into an insertion hole penetrating the yoke and the fastening plate. In a core-type reactor with a gap formed by tightening and fixing a yoke and a clamping plate, the cooling connecting member is cooled by forcibly supplying a cooling medium to the insertion hole through the gap. Yes. As the cooling medium, insulating oil is cited.

  In Patent Document 3, in an induction element including a cooling device for cooling a wire winding as a coil and a ferromagnetic core, the cooling device includes a solid solution including at least one polymer material and at least one thermally conductive filler. Formed from. Specifically, the cooling device is a film or compound having a thermally conductive solid solution. In the case of a film, the wire winding and the core are surrounded by the film and radiated through the film. In the case of a compound, the wire winding and the core are embedded (molded) in the compound, and heat is radiated through the compound.

JP-A-9-232165 JP 59-217313 A JP-T-2005-537636

  In the cooling method of Patent Document 1 described above, not only the cooling pipe and the heat conductive filler are provided, but also a mechanism for flowing the coolant in the cooling pipe is required, so the configuration is complicated and the manufacturing cost is also low. There is a drawback that it is expensive.

  In the cooling method of Patent Document 2 described above, not only is the reactor configured to have an insertion hole, but also a mechanism for forcibly supplying a cooling medium is required. The configuration is complicated and the manufacturing cost is high.

  In the cooling method of Patent Document 3 described above, it is necessary to surround the wire winding and the core with a film as a cooling device, or to embed the wire winding and the core with a compound as a cooling device, so that the manufacturing cost is high. There are difficulties. In addition, when the reactor becomes large, it becomes difficult to surround with a film or to be embedded with a compound, or to perform the process itself becomes unrealistic.

  Furthermore, according to the research of the present inventors, in order to realize a reactor for a large current of several hundreds A or more at a relatively high frequency of several kHz to several hundred kHz, in addition to solving the above-described core cooling problem. As a result, it has been found that the problem of high voltage insulation needs to be solved. Specifically, in order to maintain the insulation performance of the coil, the occurrence of corona discharge must be prevented. Hereinafter, this point will be described.

  “Corona discharge” means that in the vicinity of a conductor to which a high voltage is applied, gas molecules are ionized to generate cations and electrons, and these cations and electrons are synchronized with the change in polarity of the high voltage. It is a phenomenon in which new gas molecules are ionized or collide with insulators. When corona discharge occurs in the air, oxygen molecules in the air are ionized to generate ozone, which degrades the insulating performance of the nearby insulator. In the case of the high frequency reactor as in the present invention, corona discharge is likely to occur in the vicinity of the core and the coil, but when corona discharge occurs, the insulation performance of the insulation coating of the conductor tube constituting the coil is deteriorated. Such deterioration of the insulation performance may lead to a major accident, and must be reliably prevented.

  The degree of insulation performance deterioration due to corona discharge depends on the voltage and frequency applied to the conductor. That is. As the frequency increases, the number of occurrences of corona discharge per second increases in proportion to the frequency, so that the life of the insulator exposed to the corona discharge decreases in inverse proportion to the frequency. In addition, the higher the applied voltage, the greater the potential gradient between the high voltage application part and the ground potential part, so corona discharge is more likely to occur. The start voltage of the corona discharge is determined by the shape and distance of the electrodes of the high voltage application unit and the ground potential unit, voltage, temperature, atmospheric pressure, and the like.

Assuming that the voltage across the AC reactor (coil) is V (V), the voltage V across the inductor is L (H) as the inductance of the reactor, I (A) as the current flowing through the reactor (coil), and the frequency as f (Hz). ) Is obtained from the equation V = 2πfLI. Therefore, the higher the frequency f and the larger the current I, the higher the voltage V across the reactor. For example, when L = 100 (μH), I = 500 (A), and f = 10,000 (Hz), the voltage V across the coil is
V = 2π × 10,000 × 100 × 10 ⁻⁶ × 500 = 3,142 (V)
It becomes a high voltage. Therefore, it can be seen that the AC reactor has a voltage that easily causes corona discharge depending on the electrode shape and the distance between the electrodes.

  Further, if there is a so-called “floating potential portion” where the potential is not fixed other than the high voltage application portion and the ground potential portion between the high voltage application portion and the ground potential portion, corona discharge is more likely to occur. As described above, in an AC reactor using a core made of a ferromagnetic material as a magnetic path forming member, the portion sandwiched between the gap insulating materials of the core becomes a floating potential portion, so a high voltage with a relatively high frequency is used. When is applied, corona discharge is more likely to occur.

  As a countermeasure for preventing corona discharge, for example, a small reactor attached to a printed circuit board, such as a stabilizer for a ballast in the field of illumination as dealt with in Patent Document 3, is vacuum-impregnated with an insulating compound. Therefore, measures can be taken by eliminating the gas that is the starting point of corona discharge. However, since AC reactors for large currents of several hundred to several hundred kHz and several hundred A or more are large, vacuum impregnation with an insulating compound is large and very expensive, which is not practical.

  The present invention has been made in consideration of the circumstances as described above, and its object is to prevent deterioration of the insulation performance of the coil due to corona discharge with a simple configuration and low manufacturing cost. An object of the present invention is to provide a high-frequency reactor that can cool the core and is suitable for high-frequency and large-current applications (several kHz to several hundred kHz, several hundred A or more).

  Another object of the present invention is to prevent overheating of surrounding metal structures due to leakage magnetic flux without using a large magnetic flux shielding structure, high frequency and large current (several kHz to several hundred kHz, several An object of the present invention is to provide a high-frequency reactor suitable for applications of 100 A or more.

  Other objects of the present invention which are not specified here will be apparent from the following description and the accompanying drawings.

(1) The high frequency reactor of the present invention is
A coil that generates magnetic flux when energized;
A core having a divided region divided by a plurality of gaps and forming a magnetic path for passing the magnetic flux;
A base member that is mechanically connected to the core in a state of being electrically insulated by an insulating member, and for fixing the high-frequency reactor to a desired use location;
The core includes a plurality of core blocks are fixed in a state where a gap from one another by first fixing member and the second fixing member having conductivity,
The first fixing member fixes end portions of all the core blocks on the side close to the base member, and is mechanically connected to the base member via the insulating member, and the second fixing member Is fixing the end of all the core blocks on the side far from the base member,
The gap between the plurality of core blocks functions as a passage for the cooling medium,
The base member, the conjunction is mechanically connected to the first fixing member via an insulating member, the distance between the first fixing member and the base member, the size rather is set than the width of the gap Thus, the corona discharge caused by the contact between the core block and the cooling medium is prevented .

The high-frequency reactor of the present invention, the core, because it contains a plurality of said core block which is fixed in a state in which a gap to each other by the first fixing member and the second fixing member, wherein the core alone The exposed area can be expanded as compared with the case of. The core block, that is, the core can be effectively cooled by bringing a cooling medium (for example, air) into contact with the enlarged exposed surface. In this way, the core can be effectively cooled with a simple configuration and at a low manufacturing cost.

  In addition, the core has a divided region divided by a plurality of gaps, but the divided region is in an electrically floating state, so that the divided region becomes a floating potential portion, and therefore has a relatively high frequency. When a high voltage is applied, corona discharge is more likely to occur than when there is no parting region.

  However, the base member is mechanically connected to the first fixing member while being electrically insulated by the insulating member, and the distance between the base member and the first fixing member is Since the gap is made larger than the width of the gap, for example, when the coil is energized after the base member is set to a reference potential (for example, ground potential), most of the applied high voltage is applied to both ends of the insulating member (in other words For example, it can act between the base member and the first fixing member. Then, since the voltage acting between the coil and the core and the voltage acting on both ends of each gap are considerably small, the surface of the core (ie, the core block) is cooled. Corona discharge can be prevented from occurring even when a medium (for example, air) contacts. As a result, it is possible to prevent deterioration of the insulation performance of the coil due to corona discharge in high frequency and large current (several kHz to several hundred kHz, several hundred A or more) applications with a simple configuration and low manufacturing cost. it can.

  Further, since both ends of all the core blocks are fixed by the conductive first fixing member and the second fixing member, leakage magnetic flux generated from both ends of the core block is effectively shielded. Is done. For this reason, the overheating of the surrounding metal structure resulting from the leakage magnetic flux can be prevented without taking a large magnetic flux shielding structure.

  (2) In a preferred example of the high frequency reactor according to the present invention, a distance between the base member and the first fixing member is set to be five times or more of each size of the gap. The reason is that if it is less than 5 times, the effect of preventing corona discharge may be insufficient. In this example, there is an advantage that deterioration of the insulation performance of the coil due to corona discharge can be surely prevented.

  (3) In still another preferred example of the high-frequency reactor according to the present invention, a plurality of engagements in which the end portions on the side closer to the base member of all the core blocks are formed on the first fixing member. The end portions of the core blocks that are respectively engaged with the grooves and that are on the side far from the base member are respectively engaged with a plurality of engagement grooves formed in the second fixing member. To position all the core blocks. In this example, there is an advantage that all the core blocks can be positioned, held and fixed with a simple configuration.

(4) In still another preferred embodiment of the high frequency reactor of the present invention, the first fixing member and the second fixing member has an opening respectively communicating with the gap between the core blocks. In this example, the cooling medium passing through the gap between the core blocks, so can flow into their outwardly through the second fixing member and the first fixing member, wherein the first fixing member Even if the second fixing member is provided, there is an advantage that the cooling of the core block is performed without any trouble.

(5) In yet another preferred embodiment of the high frequency reactor of the present invention, the between the first fixing member and the second fixing member, and is exposed to the outer surface of the core block located at both ends of the core The cooling medium can be contacted . In this example, since the outer surface of the core block disposed at opposite ends of said core in contact with the cooling medium, wherein an opening for passing the cooling medium to the second fixing member and the first fixing member first There is an advantage that these two core blocks can be cooled without any trouble even if they are not provided on the first fixing member and the second fixing member.

(6) In yet another preferred embodiment of the high frequency reactor of the present invention, the first fixing member and the second fixing member, internally it has a cooling medium passage, its cooling medium passage from the outside second The cooling medium can be supplied. In this example, there is an advantage that overheating of the first fixing member and the second fixing member can be prevented.

  (7) In still another preferred example of the high frequency reactor according to the present invention, the insulating member is an insulator.

  (8) In still another preferred example of the high frequency reactor according to the present invention, the first fixing member and the second fixing member are connected to each other by an insulating connecting bolt around the plurality of core blocks. The

  (9) In still another preferred example of the high frequency reactor according to the present invention, a magnetic flux shielding structure is further provided so as to surround the core and the coil. In this example, there is an advantage that the leakage magnetic flux generated from the core block is more effectively shielded.

(10) In still another preferred example of the high frequency reactor according to the present invention, the magnetic flux shielding structure includes a shielding plate fixed to be overlapped with the first fixing member, and a shielding fixed to be overlapped with the second fixing member. And a shielding plate disposed between the first fixing member and the second fixing member so as to surround the core and the coil. In this example, there is an advantage that the magnetic flux shielding structure can be easily incorporated.
(11) In still another preferred example of the high frequency reactor of the present invention, air is used as the cooling medium.

  According to the high frequency reactor of the present invention, (a) the core can be cooled with a simple configuration and low manufacturing cost while preventing deterioration of the insulation performance of the coil due to corona discharge. (B) Leakage magnetic flux There is an effect that it is possible to prevent the surrounding metal structure from being overheated due to the fact that a large magnetic flux shielding structure is not employed.

It is a front view showing the whole high frequency reactor composition concerning a 1st embodiment of the present invention. It is a side view of the high frequency reactor which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the detail of a structure of the core and coil which are used for the high frequency reactor of FIG.1 and FIG.2. It is a side view of the coil currently used for the high frequency reactor of FIG.1 and FIG.2. It is a front view of the core block which is a component of the core used for the high frequency reactor of FIG.1 and FIG.2. It is a side view which shows the structure of the core currently used for the high frequency reactor of FIG.1 and FIG.2. FIG. 3 is a bottom view of an upper fixing plate used in the high frequency reactor of FIGS. 1 and 2. It is a top view of the lower fixed board currently used for the high frequency reactor of FIG.1 and FIG.2. (A) is the conceptual diagram explaining the principle which a corona discharge produces in a high frequency reactor, (b) is the equivalent circuit schematic. (A) is a conceptual diagram explaining the reason why corona discharge is effectively prevented in the high frequency reactor of FIGS. 1 and 2, and (b) is an equivalent circuit diagram thereof. It is a perspective view which shows the magnetic flux shielding structure used for the high frequency reactor which concerns on 2nd Embodiment of this invention. (A) is a front view which shows the whole structure of the high frequency reactor which concerns on 2nd Embodiment of this invention, (b) is the right view. It is a top view which shows the whole structure of the high frequency reactor which concerns on 2nd Embodiment of this invention. It is explanatory drawing which shows the method of fixing the upper surface copper plate used for the magnetic flux shielding structure of the high frequency reactor of FIGS. It is explanatory drawing which shows the method of fixing the lower surface copper plate used for the magnetic flux shielding structure of the high frequency reactor of FIGS.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

(First embodiment)
1 and 2 show the overall structure of a high frequency reactor 1 according to a first embodiment of the present invention.

  As can be seen from both figures, the high-frequency reactor 1 according to this embodiment includes a coil 10 that generates a magnetic flux when energized, and a core (magnetic path) that forms a magnetic path for passing the magnetic flux generated by the coil 10. Forming member) 20. The coil 10 is a solenoid coil wound a plurality of times in a substantially elliptical planar shape, and is fixed inside the core 20 (see FIG. 3). A plurality of connection terminals 11 provided on the front surface of the coil 10 protrude from the front end of the core 20. A curved rear end portion of the coil 10 protrudes from the rear end of the core 20.

  An upper fixing plate 30 (which corresponds to the second fixing member) and a lower fixing plate 40 (which corresponds to the first fixing member) are respectively disposed on the upper end and the lower end of the core 20. In other words, the core 20 is sandwiched between the upper fixing plate 30 and the lower fixing plate 40. The upper fixing plate 30 and the lower fixing plate 40 are connected to each other by eight fastening bolts 50. Each tightening bolt 50 is fixed by screwing a screw portion (not shown) formed at the lower end thereof into a screw hole 44 (see FIG. 8) of the lower fixing plate 40. A screw portion (not shown) at the upper end of each tightening bolt 50 is inserted into a through hole 34 (see FIG. 7) of the upper fixing plate 30, and a tightening nut 51 is screwed therein. In this way, the core 20 is pressed and sandwiched between the upper fixing plate 30 and the lower fixing plate 40.

  The material of the upper fixing plate 30 and the lower fixing plate 40 needs to be conductive, and is more preferably copper or aluminum having high electrical conductivity. By carrying out like this, the leakage magnetic flux which arises from the both ends of the core 20 is shielded effectively, and the overheating of the surrounding metal structure resulting from a leakage magnetic flux can be prevented. Note that the outer surfaces of the upper fixing plate 30 and the lower fixing plate 40 are not covered and remain bare.

  Since the high frequency reactor 1 according to this embodiment is intended for a current having a frequency of several kHz or more, in order to prevent the tightening bolt 50 from being overheated, the tightening bolt 50 is made of an insulator, for example, It is preferably made of FRP (fiber reinforced plastic).

  The lower fixing plate 40 is mechanically connected to the conductive base 70 having a substantially rectangular plate shape with a predetermined interval D2 by four insulating high voltage insulators 60 arranged on the opposite side of the core 20. Has been. The base 70 is formed with a plurality of through holes 71 for fixing the high frequency reactor 1. When the high frequency reactor 1 is used, for example, a base 70 may be fixed to a desired structure by inserting a bolt into the through hole 71 and screwing a nut into the end thereof. At that time, one end of a ground wire (not shown) is fixed to the base 70 by a ground wire connecting screw 72 attached to the base 70. Thus, the base 70 can be maintained at the ground potential.

  Four holding / transporting rings 33 are fixed to the upper fixing plate 30 on the side opposite to the core 20. By inserting a rope through the holding / transporting rings 33, the high-frequency reactor 1 having a large weight can be easily suspended and transported. The holding / transporting ring 33 is fixed by being screwed into a holding / transporting ring screw hole 37 formed in the upper fixing plate 30.

  As described above, since the conductive upper fixing plate 30 and the lower fixing plate 40 are disposed at the upper end portion and the lower end portion of the core 20, the leakage magnetic flux generated from the core 20 upward and downward is the upper fixing plate 30. And is effectively shielded by the lower fixing plate 40. As a result, the metal structure above the upper fixing plate 30 and the base 70 and the metal structure below the lower fixing plate 40 (including the metal structure to which the high frequency reactor 1 is fixed) are It is possible to prevent overheating.

  Since not a few eddy currents flow in the upper fixing plate 30 and the lower fixing plate 40 due to the leakage magnetic flux, even if they are made of a material having high electrical conductivity, some heat is generated. Therefore, in the present embodiment, the upper fixing plate 30 and the lower fixing plate 40 are provided with cooling mechanisms, respectively.

  That is, as shown in FIG. 7, a cooling water passage 32 is formed inside the upper fixing plate 30, and a pair of cooling water nipples 31 are attached to both ends of the cooling water passage 32, and these cooling water nipples are provided. Through 31, cooling water can be supplied to and discharged from the inside of the upper fixing plate 30. Similarly, a cooling water passage 42 is also formed inside the lower fixing plate 40, and a pair of cooling water nipples 41 are attached to both ends of the cooling water passage 42. Cooling water can be supplied to and discharged from the inside of the fixed plate 40.

  Next, the detailed structure of the coil 10 will be described.

  As shown in FIGS. 3 and 4, the coil 10 is formed by spirally winding a conductor tube 13 whose periphery is insulated and coated a predetermined number of times in order to obtain a predetermined inductance. It has a cylindrical shape. Cooling water nipples 12 are respectively attached to the upper and lower ends of the conductor tube 13, and the coil 10 can be cooled by flowing cooling water through the conductor tube 13. This is to prevent the coil 10 from being overheated by Joule heat due to the supply of high-frequency high current. For example, a copper pipe is used as the conductor pipe 13. The conductor tube 13 is covered with an insulating tape or the like. Between each winding part of the conductor tube 13 (coil 10) and between the conductor tube 13 (coil 10) and its circumference | surroundings, all are insulated.

  In the present embodiment, a plurality of connection terminals 11 are provided in the middle of the conductor tube 13 wound spirally. This is to make it possible to select and use any one of a plurality of inductance values. A desired inductance value can be obtained by selecting two connection terminals 11 that can obtain a desired inductance value and supplying a high-frequency current thereto.

  Next, the detailed structure of the core 20 will be described.

  The core 20 is not a single member, but is configured by combining seven core blocks 21 having the same configuration as clearly shown in FIGS. 3, 5, and 6. In other words, the core 20 is divided into seven core blocks 21. These core blocks 21 are made of ferrite here, but are not limited thereto, and may be made of another ferromagnetic material (for example, a silicon steel plate). The outer surfaces of these core blocks 21 are not covered and remain bare.

  The seven core blocks 21 are arranged in parallel at equal intervals along one direction (here, the front-rear direction) in the same posture, and are held and fixed by the upper fixing plate 30 and the lower fixing plate 40. ing. A gap between adjacent core blocks 21 serves as a cooling medium passage 22.

  In order to hold and fix the seven core blocks 21 at equal intervals in the same posture, the lower fixing plate 40 is configured as shown in FIG. That is, seven substantially rectangular core block engagement grooves (recesses) 45 are formed at a predetermined interval in the front-rear direction, and each of the core block engagement grooves 45 has a lower portion 21e of the core block 21. The tip of the is engaged. Since the size of the core block engaging groove 45 is slightly larger than that of the lower portion 21e of the core block 21, it is possible to receive and support the lower portion 21e at the bottom of the core block engaging groove 45. . For this reason, the positioning of the lower end portion of the core block 21 is completed by engaging the tip of the lower portion 21 e with the core block engaging groove 45.

  A cooling medium slit 46 is formed between the adjacent core block engaging holes 45, and the cooling medium slit 46 is positioned between the adjacent core blocks 21. For this reason, the cooling medium passage 22 between the adjacent core blocks 21 overlaps with the cooling medium slit 46, and the cooling medium passage 22 communicates with the lower fixing plate 40 through the cooling medium slit 46. Can do. As a result, the air that is the cooling medium smoothly flows through the cooling medium passage 22, and a desired cooling effect for the core block 21 (and thus the core 20) is obtained.

  The lower fixing plate 40 is further formed with a lever fixing screw through hole 43 and a tightening bolt screw hole 44 (see FIG. 8). The insulator fixing screw 61 inserted through the insulator fixing screw through hole 43 passes through the lower fixing plate 40 and is then screwed into the upper screw hole of the insulator 60, whereby the upper portion of the insulator 60 is attached to the lower fixing plate 40. Fixed. The lower portion of the insulator 60 is fixed by an insulator fixing screw (not shown) that is inserted from below the base 70 and penetrates the base 70. In this way, the insulator 60 is fixed between the lower fixing plate 40 and the base 70 as shown in FIG. The height of the insulator 60 is equal to the distance D <b> 2 between the lower fixing plate 40 and the base 70. The fastening bolt 50 is screwed into the fastening bolt screw hole 44 at one end thereof.

  The above-described cooling water passage 42 is formed in the vicinity of the front end of the lower fixing plate 40, and cooling water nipples 41 are respectively attached to both ends of the cooling water passage 42.

  As shown in FIG. 7, the upper fixing plate 30 has a point where the lever fixing screw through hole 43 is not formed and a tightening bolt through hole 34 instead of the tightening bolt screw hole 44. Except for this point, the configuration is the same as that of the lower fixing plate 40. That is, seven substantially rectangular core / block engagement grooves (recesses) 35 are formed at the same interval as the core / block engagement grooves 45 of the lower fixing plate 40 in the front-rear direction. The tip of the upper portion 21d of the core block 21 is engaged with each of the grooves 35. Since the size of the core block engaging groove 35 is slightly larger than that of the upper portion 21d of the core block 21, it is possible to receive and support the upper portion 21d at the top of the core block engaging groove 35. . For this reason, the positioning of the upper end portion of the core block 21 is completed by engaging the tip of the upper portion 21 d with the core block engaging groove 35.

  A cooling medium slit 36 is formed between adjacent core block engaging grooves 35, and the cooling medium slit 36 is positioned between adjacent core blocks 21. For this reason, the cooling medium passage 22 between the adjacent core blocks 21 overlaps with the cooling medium slit 36, and the cooling medium passage 22 communicates with the upper fixing plate 40 through the cooling medium slit 36. Can do. As a result, air as the cooling medium smoothly flows through the cooling medium passage 22, and a desired cooling effect on the core 20 is obtained.

  The above-described cooling water passage 32 is formed in the vicinity of the front end of the upper fixing plate 30, and cooling water nipples 31 are respectively attached to both ends of the cooling water passage.

  In this way, the cooling medium passage 22 between the adjacent core blocks 21 overlaps and communicates with the cooling medium slits 36 and 46 located above and below the cooling medium passage 22, so that the air as the cooling medium is The inside becomes six layers and flows through vertically. In addition, the outer surfaces of the two core blocks 21 at both ends (front end and rear end) of the core 20 are also in contact with the air as the cooling medium, and the air can freely flow. Thus, since air can flow over the entire surface of each core block 21, a desired cooling effect can be obtained for each core block 21 (ie, core 20) only by natural convection of air. It is done.

  In the present embodiment, the cooling medium that passes through the cooling medium passage 22 is air. Further, the air as the cooling medium passes through the cooling medium passage 22 by natural convection. However, if the cooling effect is insufficient by natural convection, a forced cooling fan is attached below the lower fixed plate 40 so that air as a cooling medium is forced to pass through the cooling medium passage 22. Good. That is, if necessary, a forced cooling structure may be used.

  In an experiment by the present inventor, when ferrite is used as the material of the core block 21, natural convection without using a fan is used until the core loss per unit weight of the core block 21 (core 20) is approximately 15 W / kg. With the air cooling (air cooling), continuous use was possible without overheating the core block 21.

  As shown in FIG. 5, the core block 21 is formed by hollowing out two rectangular through holes 21c from a rectangular plate having a constant thickness. The portion between the two through holes 21c is the central portion 21a, and the portions disposed on the left and right sides of the central portion 21a are the end portions 21b. The upper ends of the central portion 21a and the two end portions 21b are connected to each other by an upper portion 21d. The lower ends of the central portion 21a and the two end portions 21b are connected to each other by a lower portion 21e. In this way, the overall shape of the core block 21 is a shape in which the Chinese character “day” is laid sideways. The coil 10 is disposed through the through hole 21c so as to surround the central portion 21a (see FIG. 3).

  The magnetic path through which the magnetic flux generated by the coil 10 passes passes from the central portion 21a of the core block 21 through the upper portion 21d (or the lower portion 21e), the left and right end portions 21b, and the lower portion 21e (upper portion 21d). The route returns to the central portion 21a. Although this magnetic flux is likely to leak from the upper part 21d and the lower part 21e, since the conductive upper fixing plate 30 and the lower fixing plate 40 are arranged in close contact with each other, most of the leakage magnetic flux is fixed to the upper fixing plate 30 and the lower fixing plate 30. It is effectively blocked by the plate 40.

  As shown in FIGS. 5 and 6, a plurality of gaps 21f (the size of the gap is D1) for generating a desired magnetic resistance in the magnetic path is formed in the central portion 21a and the left and right end portions 21b of the core block 21. ) And the sum of the sizes D1 of these gaps 21f is made equal to the required gap value. These gaps 21 f are filled with a thin insulating gap plate (gap insulating material) 23. The gap plate 23 is formed by molding an insulating material. It is preferable that the thickness of the gap plate 23 (the size of the gap 21f) is small because the leakage magnetic flux is reduced. The thickness of the gap plate 23 (the size of the gap 21f) is, for example, preferably 10 mm or less, more preferably 5 mm or less.

  Since the central portion 21a and the end portion 21b of the core block 21 are divided by the gap plate 23 (gap 21f), the portion sandwiched between the two adjacent gap plates 23 (gap 21f) 24 (referred to as “divided region”) is not electrically connected anywhere. That is, when the coil 10 is energized, each divided region 24 is in an electrically floating state (electrically floating state), and its potential is at a floating potential. Since both the upper fixing plate 30 and the lower fixing plate 40 are conductors, the core upper portion 21d has the same potential as the upper fixing plate 30 and the core lower portion 21e has the same potential as the lower fixing plate 40.

As already described, the voltage V (V) across the coil 10 of the high frequency reactor 1 is L (H) as the inductance of the reactor 1, I (A) as the current supplied to the reactor 1, and f ( Hz), V = 2πfLI. Therefore, the higher the frequency f and the larger the current I, the higher the voltage V across the coil 10 (reactor 1). For example, when f = 10,000 (Hz), L = 100 (μH), and I = 500 (A), the voltage V between both ends is
V = 2π × 10,000 × 100 × 10 ⁻⁶ × 500 = 3,142 (V)
High voltage. Therefore, it can be seen that the corona discharge is highly likely to occur on the surface of the core block 21 in contact with air.

  Moreover, in the high frequency reactor 1 of the present embodiment, since there are a large number of divided regions 24 at the floating potential, corona discharge is more likely to occur. When corona discharge occurs in the air adjacent to the core block 21, there arises a problem that the insulation performance of the coil 10 is deteriorated, specifically, the life of the insulation coating of the conductor tube 13 is shortened. As a result, the high frequency reactor 1 may eventually cause a dielectric breakdown. Since the life of the insulation coating of the conductor tube 13 is shortened in inverse proportion to the frequency of the current supplied to the high frequency reactor 1, the higher the frequency, the higher the need to prevent corona discharge.

  Since the high frequency reactor 1 of the present embodiment is for high currents of several hundreds of A to a high frequency of several kHz to several hundred kHz, the necessity for preventing corona discharge is extremely high. Is effectively prevented. The reason will be described with reference to FIG. 9 and FIG.

  In general, a small amount of positive ions and stray electrons generated by ultraviolet rays and cosmic rays are always present in the air. For this reason, even when an AC voltage is simply applied between the electrodes, if the potential gradient exceeds a critical value because the voltage is high (in other words, if the voltage applied between the electrodes exceeds the corona discharge start voltage) ), Corona discharge easily occurs. In addition, after the start of corona discharge, it exists around the electrode due to α action (ionization generated when electrons collide with molecules in the air) and γ action (secondary electron emission generated when cations collide with the cathode). As the number of electrons and cations increases, the corona discharge tends to continue, and as a result, the corona discharge extinction voltage is much lower than the corona discharge start voltage. In other words, once corona discharge begins, it does not disappear easily.

  Furthermore, if electrons or cations are generated around the electrode due to other factors (for example, creeping discharge), corona discharge is generated with a very low potential gradient. That is, when there is creeping discharge, the corona discharge starting voltage is extremely low.

  FIG. 9A is a conceptual diagram when the lower part 21e of the core block and the lower fixing plate 40 are connected to the ground potential, and FIG. 9B is an equivalent circuit diagram thereof. FIG. 10A is a conceptual diagram when the lower fixing plate 40 connected to the lower part 21e of the core block described above is connected to the ground potential via the insulator 60, that is, with a gap D2. 10 (b) is an equivalent circuit diagram thereof.

  In the case of FIG. 9A, considering the potential change in the path (path AB) from the point A (conductor tube 13 of the coil 10) to the point B (lower part 21e of the core block 21), FIG. ), The voltage V0 applied between the paths A and B is equal to the capacitance of the two gap plates 23, the capacitance of the air between the dividing region 24 and the conductor tube 13, and the voltage of the conductor tube 13. The pressure is divided by the capacitance of the insulating coating 13a. In other words, the applied voltage V0 is divided into both-ends voltages V1 and V2 of the capacitance of the two gap plates 23, both-ends voltage V3 of the capacitance due to air, and both-ends voltage V4 of the capacitance of the insulating coating 13a. . In this state, when the applied voltage V0 is several thousand volts, the both-end voltages V1, V2, V3, and V4 are also several hundred volts or more, so corona discharge can easily occur on the surface of the core block 21. A state arises.

  Further, the size of the gap 21f formed in the core block 21 (the thickness of the gap plate 23) D1 is usually several mm or less and sometimes 0.5 mm or less, but the both-end voltage V1 or V2 is It acts on such a narrow gap 21f, and the surface potential of electrons or cations is present on the surface of an insulating material such as the gap plate 23 and the insulating coating 13a. It is in.

  For this reason, in the case of FIG. 9A in which the lower part 21e of the core block is directly connected to the ground potential, it is understood that there is a very high possibility that corona discharge will occur on the surface of the core block 21. .

  The distance between the dividing region 24 and the conductor tube 13 is, for example, about 10 mm, which is sufficiently larger than the size of the gap 21f (the thickness of the gap plate 23) D1, but is generated from the surface of the core block 21. Corona discharge is likely to occur under the influence of positive ions and electrons accompanying the discharge.

  In the case of FIG. 10A, a path (path A-B-C) from point A (conductor tube 13 of coil 10) to point C (base 70) through point B (lower part 21e of core block 21). ), The voltage V0 applied between the paths A and C is equal to the capacitance of the two gap plates 23 and between the dividing region 24 and the conductor tube 13 as shown in FIG. In addition to the electrostatic capacity of the air and the insulating film 13a of the conductor tube 13, the electrostatic capacity of the insulator 60 and the static air due to the air between the lower part 21e of the core block 21 and the base 70 in parallel therewith. Divided by the electric capacity. That is, the applied voltage V0 includes the two end voltages V1 and V2 of the electrostatic capacity of the two gap plates 23, the both end voltage V3 of the electrostatic capacity due to air, the both end voltage V4 of the electrostatic capacity of the insulating coating 13a, and the insulator 60. And a voltage V5 between both ends of the electrostatic capacitance in parallel with the electrostatic capacitance.

  The height of the insulator 60, that is, the distance D2 between the lower fixing plate 40 connected to the lower portion 21e of the core block 21 and the base 70 is usually about 80 mm, and the size of the gap 21f (the thickness of the gap plate 23). I) Since it is overwhelmingly larger than D1 (D2 >> D1), most of the applied voltage V0 acts on both ends of the electrostatic capacity of the insulator 60 and air parallel thereto. As a result, the both-ends voltage V5 of the electrostatic capacity by the insulator 60 and the electrostatic capacity by the air parallel thereto is a value close to the applied voltage V0, and the other both-end voltages V1, V2, V3 and V4 become very small. Therefore, the possibility that creeping discharge occurs can be reduced.

  For example, depending on the ratio of the distances D2 and D1, even when the applied voltage V0 is several thousand volts, the both-end voltages V1, V2, V3, and V4 can be suppressed to about 100 volts or several tens of volts or less, respectively. It can be seen that corona discharge is unlikely to occur on the surface between the adjacent divided regions 24 or between the divided regions 24 and the conductor tube 13.

  Further, the distance from the point A (the conductor tube 13 of the coil 10) to which the applied voltage V0 is applied to the point C (base 70) is overwhelmingly larger than in the case of FIG. The potential gradient itself between the points C becomes very small, and as a result, corona discharge is difficult to occur.

  For this reason, corona discharge can be effectively suppressed in the high-frequency reactor 1 of the present embodiment in which the lower portion 21e of the core block is connected to the base 70 via the insulator 60.

  In summary, in the high-frequency reactor 1 of the present embodiment, the upper fixing plate 30, the lower fixing plate 40 and the core block 21 that are close to the high voltage portion and cause corona discharge are not fixed to the ground potential, but instead. Further, the high-voltage insulator 60 is insulated from the ground potential. In this way, most of the applied voltage V0 is applied to the high voltage insulator 60, and the voltages applied to the upper fixing plate 30, the lower fixing plate 40 and the core block 21 are significantly reduced, and corona discharge is generated. It has a difficult structure.

  The distance D2 between the lower fixing plate 40 mechanically connected to the base 70 via the insulator 60 and the base 70 is adjusted by the applied voltage V0 and the frequency f. For example, the gap 21f is large. It is preferable that the thickness is not less than 5 times D1. The reason is that if it is less than 5 times, the effect of preventing corona discharge may be insufficient. In this example, there is an advantage that deterioration of the insulation performance of the coil due to corona discharge can be surely prevented.

  As described above in detail, the high-frequency reactor 1 according to the present embodiment is electrically connected by the coil 10 that generates magnetic flux when energized, the core 20 having the divided region 24 divided by the plurality of gaps 21f, and the insulator 60. And a base 70 for fixing the high-frequency reactor 1 mechanically connected to the core 20 in an electrically insulated state at a desired use location. The core 20 includes a plurality of core blocks 21 fixed in a state of being spaced apart from each other by a conductive lower fixing plate 40 and an upper fixing plate 30. The lower fixing plate 40 fixes the ends of all the core blocks 21 on the side close to the base 70 and is mechanically connected to the base 70 via the lever 60. The upper fixing plate 30 is connected to all the core blocks 21. -The end of the block 21 on the side far from the base 70 is fixed. The base 70 is mechanically connected to the lower fixing plate 40 via an insulator 60, and the distance D2 between the base 70 and the lower fixing plate 40 is larger than the gap size (width) D1. .

  As described above, since the core 20 includes the plurality of core blocks 21 fixed with the lower fixing member 40 and the upper fixing member 30 spaced apart from each other, the core 20 is exposed as compared with the case where the core 20 is a single body. The area can be enlarged. The core block 21, that is, the core 20 can be effectively cooled by bringing a cooling medium (for example, air) into contact with the enlarged exposed surface.

  Therefore, it is possible to cool the core 20 with a simple configuration and low manufacturing cost.

  Further, the core 20 has a divided region 24 divided by a plurality of gaps 21f. Since the divided region 24 is in an electrically floating state, the divided region 24 becomes a floating potential portion. When a large current having a relatively high frequency is supplied, corona discharge is more likely to occur than when the divided region 24 is not provided.

  However, the base 70 is mechanically connected to the core 20 and the lower fixing plate 40 in an electrically insulated state by the insulator 60, and the distance D2 between the base 70 and the lower fixing plate 40 is a gap. Since the size is larger than the size D1 of 21f, when the coil 70 is energized after setting the base 70 to the ground potential (reference potential), most of the applied high voltage is applied to both ends of the insulator 60 (in other words, the base 70). 70 and the lower fixing plate 40). Then, since the voltage acting on both ends of the gap 21f is considerably small, even if air as a cooling medium contacts the surface of the core 20, it is possible to prevent corona discharge from occurring. As a result, it is possible to prevent deterioration of the insulation performance of the coil 10 due to corona discharge in high frequency and large current (several kHz to several hundred kHz, several hundreds A or more) applications with a simple configuration and low manufacturing cost. it can.

  As a result, high reliability and a long life can be obtained even if a high current of several hundred A or more is passed through the high frequency reactor 1 at a high frequency of several kHz to several hundred kHz.

  Furthermore, since both ends of all the core blocks 21 are respectively fixed by the conductive lower fixing plate 40 and the upper fixing plate 30, the leakage magnetic flux generated from both ends of the core block 21 is effectively shielded. . For this reason, the overheating of the surrounding metal structure resulting from the leakage magnetic flux can be prevented without taking a large magnetic flux shielding structure.

  The high frequency reactor 1 of the present embodiment further has the following advantages.

  Since the upper and lower fixing plates 30 and 40 have cooling medium slits 36 and 46 (openings) respectively communicating with the cooling medium passage 22 between the adjacent core blocks 21, there are upper and lower fixing plates 30 and 40. However, the cooling of the core block 21 is performed without any trouble.

  The upper and lower fixing plates 30 and 40 have cooling water passages 32 and 42 therein, respectively, and cooling water can be supplied to the passages 32 and 42 from the outside. 40 overheating can be prevented.

(Second Embodiment)
Next, a high frequency reactor 1A according to a second embodiment of the present invention will be described with reference to FIGS.

  1 A of high frequency reactors of 2nd Embodiment add the magnetic flux shielding structure 100 which covers the circumference | surroundings (to be exact, the 5th surface in six surfaces) with respect to the high frequency reactor 1 of 1st Embodiment mentioned above. It is. Therefore, about the same structure as the high frequency reactor 1 of 1st Embodiment, the code | symbol same as the reactor 1 is attached | subjected and the description is abbreviate | omitted.

  The overall structure of the magnetic flux shielding structure 100 is as shown in FIG. That is, the magnetic flux shielding structure 100 has a substantially rectangular parallelepiped shape, and only the front surface (front surface) of the six surfaces is opened, and the other five surfaces (rear surface, upper and lower surfaces, left and right side surfaces) are rectangular upper surfaces. The copper plate 81, the lower copper plate 82, the left copper plate 83, the right copper plate 84, and the rear copper plate 85 are closed. Since the cooling water nipples 12 and 41 and the connection terminal 11 of the coil 10 are exposed from the front opening 89 on the front surface of the magnetic flux shielding structure 100, it is easy to connect piping for cooling water supply and connection of electric wires. Therefore, there is no hindrance and no inconvenience in using the high frequency reactor 1A.

  Further, since there is a sufficient gap 90 between the magnetic flux shielding structure 100 (that is, the upper surface copper plate 81, the lower surface copper plate 82, the left side copper plate 83, the right side copper plate 84 and the rear copper plate 85), the core 20 and the coil 10. There is no problem in the flow of air as a cooling medium for cooling the core 20 and the coil 10.

  As shown in FIG. 14, the rectangular upper copper plate 81 is disposed on the outer surface (upper surface) of the same rectangular upper fixing plate 30 and allows the holding / transporting ring 33 to pass through a through hole formed at a corresponding position. Thus, the outer surface is fixed. Since the upper surface copper plate 81 is slightly larger than the upper fixing plate 30, there are portions P <b> 1 protruding parallel to the four sides of the upper fixing plate 30 (see FIG. 13). These protruding portions P1 have a rectangular ring shape as a whole. The left and right side surface copper plate fixing members 87 and the rear surface copper plate fixing member 88 are fixed to these protruding portions P1 by a plurality of screws 91.

  As shown in FIG. 15, the rectangular lower surface copper plate 82 is disposed on the outer surface (lower surface) of the same rectangular lower fixing plate 40, and allows the insulator fixing screws 61 to pass through through holes formed at corresponding positions. , Fixed to the outer surface. Since the lower surface copper plate 82 is slightly larger than the lower fixing plate 40, there are portions P <b> 2 projecting parallel to the four sides of the lower fixing plate 40. These protruding portions P2 have a rectangular ring shape as a whole. The left and right side surface copper plate fixing members 87 and the rear surface copper plate fixing member 88 are also fixed to these protruding portions P <b> 2 by a plurality of screws 91.

  Left and right side copper plate fixing members 87 and rear copper plate fixing members 88 fixed to the protruding portion P1 of the upper surface copper plate 81, and left and right side copper plate fixing members 87 and rear surface copper plate fixing members 88 fixed to the protruding portion P2 of the lower surface plate 82. Column members 86 are bridged up and down at four corners. The four column members 86 are coupled to the side copper plate fixing member 87 and the rear copper plate fixing member 88 by a plurality of screws 91. Thus, a cuboid skeleton is formed as a whole.

  The outer edge portion of the left side copper plate 83 is brought into contact with the front and rear two pillar members 86 and the upper and lower two side copper plate fixing members 87 on the left side surface of the skeleton, and screw holes 86a formed in the outer edge portion. The screw 91 is inserted into the screw 87 a and screwed into the column member 86 and the side copper plate fixing member 87. The left side copper plate 83 covers the entire left side surface of the magnetic flux shielding structure 100.

  The outer edge portion of the right side copper plate 84 is brought into contact with the front and rear two column members 86 and the upper and lower side copper plate fixing members 87 on the right side surface of the skeleton, and screw holes 86a formed on the outer edge portion. The screw 91 is inserted into the screw 87 a and screwed into the column member 86 and the side copper plate fixing member 87. The right side copper plate 84 covers the entire right side surface of the magnetic flux shielding structure 100.

  The outer edge portion of the rear copper plate 85 is brought into contact with the two left and right column members 86 and the upper and lower two rear copper plate fixing members 88 on the rear surface of the skeleton, and screw holes 86a and 88a formed in the outer edge portion. By inserting and screwing the screw 91, the column member 86 and the rear copper plate fixing member 88 are fixed. The rear copper plate 85 covers the entire rear surface of the magnetic flux shielding structure 100.

  As described above, the magnetic flux shielding structure 100 is closed by the upper surface copper plate 81, the lower surface copper plate 82, the left side copper plate 83, the right side copper plate 84 and the rear surface copper plate 85 except for the front surface (front surface) of the substantially rectangular parallelepiped skeleton. It has been done.

  Here, as the pillar member 86, the side copper plate fixing member 87, and the rear copper plate fixing member 88, brass angle members having an L-shaped cross section are used. This is because it has the necessary rigidity and is inexpensive. However, it goes without saying that materials other than angle materials, such as square materials, can also be used. Moreover, it is preferable that the pillar member 86, the side copper plate fixing member 87, and the rear copper plate fixing member 88 are made of a metal material having high conductivity, for example, brass, copper, aluminum, or the like.

  The upper surface copper plate 81 is fixed to the outer surface (upper surface) of the upper fixed plate 30 so as to overlap therewith. However, as shown in FIG. 11, the tightening bolt through holes 34 and the cooling medium slit 36 of the upper fixed plate 30. Since the through holes 81a, the slits 81c, and the through holes 81b are provided at positions overlapping with the holding / transporting ring screw holes 37, the air as the cooling medium flowing through the cooling medium passage 22 of the core 20 is It can move to the outside (upward) from the upper surface copper plate 81 through the cooling medium slit 36. Further, the fastening bolt 50 can be inserted into the fastening bolt through hole 34 of the upper fixed plate 30 from the outside of the upper surface copper plate 81 and screwed into the fastening bolt through hole 44 of the lower fixed plate 40. The holding / transporting ring 33 can be screwed into the holding / transporting ring screw hole 37 of the upper fixed plate 30 from the outside of the copper plate 81.

  The lower surface copper plate 82 is fixed to the outer surface (lower surface) of the lower fixed plate 40 so as to overlap therewith, but the slit is provided at a position overlapping with the cooling medium slit 46 and the insulator fixing screw through hole 43 of the lower fixed plate 40. And through holes (both not shown), the air as the cooling medium flowing through the cooling medium passage 22 of the core 20 passes through the cooling medium slit to the outside (downward) from the lower surface copper plate 82. Can move. Further, the insulator fixing screw 61 can be screwed into the insulator 60 from the lower fixing plate 40 side through the insulator fixing screw through hole 43 and through the through hole of the lower surface copper plate 82.

  As described above, in the high frequency reactor 1 </ b> A according to the second embodiment of the present invention, the magnetic flux shielding structure 100 effectively shields the magnetic flux, which is compared with the high frequency reactor 1 according to the first embodiment described above. However, the structure is slightly complicated and the manufacturing cost is slightly increased. However, it is possible to surely prevent the metal structure located in a position very close to the core 20 from overheating due to the leakage magnetic flux. Is further obtained.

  The cooling medium passage 22 of the core 20 passes through the slit 36 of the upper fixing plate 30, the slit 81 c of the upper surface copper plate 81, the slit 46 of the lower fixing plate 40, and the slit of the lower surface copper plate 82, and then to the outside of the magnetic flux shielding structure 100. Therefore, the cooling capacity of the core 20 does not decrease due to the mounting of the magnetic flux shielding structure 100.

(Modification)
The embodiments described above show examples embodying the present invention. Therefore, the present invention is not limited to this embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

  Further, depending on the inductance value of the high frequency reactor 1 and the number of turns / current of the coil 10, it may not be necessary to cool the upper fixing plate 30 and the lower fixing plate 40. In that case, the cooling water passages 32 and 42 and the cooling water nipples 31 and 41 provided in the upper fixing plate 30 and the lower fixing plate 40 can be omitted.

  The shapes and materials of the coil 10 and the core 20 and the shapes and materials of the upper fixing plate 30 and the lower fixing plate 40 are not limited to those shown in the above-described embodiments, and can be arbitrarily changed.

  In the embodiment described above, the core 20 combines the plurality of core blocks 21 and the upper and lower fixing plates 30 and 40 (in other words, a pair of fixing members) after separately producing them. It is not limited. A pair of fixing members may be integrally formed with a plurality of core blocks.

DESCRIPTION OF SYMBOLS 1, 1A High frequency reactor 10 Coil 11 Connection terminal 12 Cooling water nipple 13 Conductor tube 13a Insulation coating 20 of conductor tube Core 21 Core block 21a Center part 21b End part 21c Through-hole 21d Upper part 21e Lower part 21f Gap 22 Cooling medium passage 23 Gap plate 24 Dividing region 30 Upper fixed plate 31 Cooling water nipple 32 Cooling water passage 33 Holding / transporting ring 34 Tightening bolt through hole 35 Core / block engagement groove 36 Cooling medium slit 37 Holding / transporting ring screw Hole 40 Lower fixing plate 41 Cooling water nipple 42 Cooling water passage 43 Insulator fixing screw through hole 44 Tightening bolt screw hole 45 Core / block engagement groove 46 Cooling medium slit 50 Tightening bolt 51 Tightening nut 60 High pressure Insulator 61 Insulator fixing screw 70 Base 71 Through hole 72 Ground wire connection screw 81 Upper surface copper plate 81a 81b Through-hole 81c Slit 82 Face copper plate 83 Left side copper plate 84 Right side copper plate 85 Rear copper plate 86 Column member 86a Screw hole 87 Side copper plate fixing member 87a Screw hole 88 Rear copper plate fixing member 88a Screw hole 89 Front opening 90 Clearance 91 Screw 100 Magnetic flux shielding structure D1 Gap size (gap plate thickness)
D2 Distance between the lower part of the core block and the base P1 Projected part of the upper copper plate P2 Projected part of the lower copper plate

Claims (11)

A coil that generates magnetic flux when energized;
A core having a divided region divided by a plurality of gaps and forming a magnetic path for passing the magnetic flux;
A base member that is mechanically connected to the core in a state of being electrically insulated by an insulating member, and for fixing the high-frequency reactor to a desired use location;
The core includes a plurality of core blocks are fixed in a state where a gap from one another by first fixing member and the second fixing member having conductivity,
The first fixing member fixes end portions of all the core blocks on the side close to the base member, and is mechanically connected to the base member via the insulating member, and the second fixing member Is fixing the end of all the core blocks on the side far from the base member,
The gap between the plurality of core blocks functions as a passage for the cooling medium,
The base member, the conjunction is mechanically connected to the first fixing member via an insulating member, the distance between the first fixing member and the base member, the size rather is set than the width of the gap A high frequency reactor characterized by preventing corona discharge caused by contact between the core block and the cooling medium .   2. The high frequency reactor according to claim 1, wherein a distance between the base member and the first fixing member is not less than five times the size of each of the gaps.   The end portions of all the core blocks on the side close to the base member are respectively engaged with a plurality of engagement grooves formed in the first fixing member, and the base members of all the core blocks The end portion on the side farther from the center is respectively engaged with a plurality of engaging grooves formed in the second fixing member, thereby positioning all the core blocks. 2. The high frequency reactor according to 2. Wherein the first fixing member second fixing member, a high-frequency reactor according to claim 1, wherein has an opening for each communicating with the gap between the core blocks. The outer surface of the said core block located in the both ends of the said core is exposed between the said 1st fixing member and the said 2nd fixing member, and it can contact the said cooling medium . The high frequency reactor according to any one of the above. The said 1st fixing member and the said 2nd fixing member have a cooling-medium channel | path inside, The 2nd cooling medium can be supplied to the cooling-medium channel | path from the outside . The high frequency reactor described in Crab.   The high frequency reactor according to claim 1, wherein the insulating member is an insulator.   The high frequency reactor according to any one of claims 1 to 7, wherein the first fixing member and the second fixing member are connected to each other by an insulating connecting bolt around the plurality of core blocks.   The high frequency reactor according to any one of claims 1 to 8, further comprising a magnetic flux shielding structure disposed so as to surround the core and the coil.   The magnetic flux shielding structure is disposed between the first fixing member and the second fixing member, the shielding plate fixed to the first fixing member, and the shielding plate fixed to the second fixing member. The high frequency reactor according to claim 9, further comprising a shielding plate disposed so as to surround the core and the coil. The high frequency reactor according to claim 1, wherein air is used as the cooling medium.

Images