KR100469117B1 - Noise-cut filter for power converter - Google Patents

Abstract

It is an object of the present invention to provide a sufficient current capacity to cope with low frequency noise and to provide a compact and inexpensive noise filter that can be easily mounted on a substrate by being manufactured by a simple manufacturing process, has excellent reliability.

The coil patterns 2a and 2b having the function of the inductor are disposed on both sides of the dielectric sheet 1, and have a cross-sectional area that allows the main circuit current to flow through the coil pattern 2a and has the same shape as the coil pattern 2a. The first main circuit pattern 4a is formed by joining the punched main circuit conductors 3a to the coil pattern 2b through the dielectric sheet 1 from the first main circuit pattern 4a. By inducing a noise current to ground, a noise filter having the function of an inductor and a capacitor is constructed.

Description

Noise filter {NOISE-CUT FILTER FOR POWER CONVERTER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a noise filter for filtering switching noise generated in accordance with switching operations of semiconductor switch elements constituting a power converter such as an inverter.

The switching operation of a semiconductor switch element constituting a power converter such as an inverter is performed based on a pulse width modulated (PWM) drive signal having a carrier frequency of several KHz to several tens of KHz. Switching noise comes from the power converter.

In recent years, in order to suppress the adverse effect which a component of 100 KHz or more among the frequency components of the said switching noise gives to an external apparatus, various legal regulations are enforced in a power converter. To cope with such regulations, noise filters for power converters are attached to the power converters.

Background Art Conventionally, as a noise filter for a power converter of this kind, a single reactor formed by winding an electric wire around a core made of ferrite, an amorphous alloy, a crystalline alloy, or the like, and a single capacitor made of a film, a chip, or the like are connected in an inverted L shape, for example. The noise filter is configured to filter the switching noise generated in accordance with the switching operation of the semiconductor switch element by the noise filter.

Moreover, as a well-known document regarding a noise filter for a power converter, it is disclosed by the "Integrated 0utput Filter and Diode Snubber for Switchmode Power Converters" described on page 1240-1245 of the literature by IEEE in 1994 as the well-known document 1, for example. have. This proposes a filter circuit in which the rectifier, the RC snubber circuit, and the LC filter circuit have an integrated flat plate structure, and also gives a basic description of the manufacturing method in each circuit.

Further, as known document 2 for the noise filter for power converter described above, it is disclosed in 1995 "Integrated Filters For Switch-Mode Power Supplies" described on page 809-816 of the document by the IEEE. This is proposed by dividing the structure of the LC filter circuit into three types based on the dielectric material. That is, the dielectric is divided into a ceramic structure and a non-ceramic structure, and one type of flat plate structure (type made of BaTiO ₃ ) as the ceramic structure and two types of film structure (sheet type and deposition type by plasma) as the non-ceramic structure. ) Is proposed.

However, conventionally, the reactor used as this kind of noise filter generally has a toroidal shape, and the capacitor has a pin insertion type, a planar shape or a cylindrical shape, and the like is placed on the printed board inside the power converter. In the case of mounting to, the mounting space of each volume or more is required, and there is a problem in terms of assemblability. In addition, in the case where these kinds of noise filters are attached by individual wiring, there are problems in that there are many connection locations and the fixing method of each component is complicated.

In addition, in the so-called complex LC filter of chip type or pin insertion type which combines inductors and capacitors on the market, the cut-off frequency is several MHz or more, whereas switching noise generated by switching operations of semiconductor switch elements constituting power converters such as inverters. The cutoff frequency required to filter P is as low as, for example, 150 KHz, and cannot be used as a commercially available filter.

In addition, in a power converter such as an inverter, it is desired to pass a current of several amps or more to a noise filter to be used, but it is difficult to employ a commercially available composite LC filter in terms of current capacity and cost.

In addition, in the known documents 1 and 2, the manufacturing method is not complicated and practical, and there is also a problem in terms of cost.

Accordingly, an object of the present invention is to provide a noise filter that can secure a sufficient current capacity and can cope with low frequency noise.

In addition, another object of the present invention is to provide a noise filter which is easy to mount on a substrate, which is excellent in reliability, and which is small and inexpensive by being manufactured by a simple manufacturing process.

The present invention provides a flat plate-like dielectric sheet, a spiral coil pattern formed opposite to both sides of the first dielectric sheet, having a function of an inductor, and made of a conductive paste, and formed on one side of the first dielectric sheet. A first main circuit pattern formed by bonding a first main circuit conductor press-punched into the same shape as the coil pattern and having a cross-sectional area through which a desired current value flows on the coil pattern; and a side opposite to the first main circuit pattern A first ground line bonded to the coil pattern formed in the first ground circuit, the first ground line for inducing a current based on noise flowing from the first main circuit pattern into the coil pattern through the first dielectric sheet to ground; Is formed to face both sides of the second dielectric sheet and has a function of an inductor and is made of a conductive paste. Is formed by joining a spiral main coil pattern and a second main circuit conductor press-punched into the same shape as the coil pattern and having a cross-sectional area for passing a desired current value on the coil pattern formed on one side of the second dielectric sheet. A second main circuit pattern, and a current based on noise that is bonded to the coil pattern formed on an opposite side to the second main circuit pattern and flows into the coil pattern from the second main circuit pattern through the second dielectric sheet And a second ground line for directing to the ground, and a flat insulating sheet inserted between the first dielectric having the first main circuit pattern and the second dielectric having the second main circuit pattern. By connecting one end of the first main circuit conductor and one end of the second main circuit conductor, the other end which is not connected is used as an input / output terminal. The first and the second dielectric material having the first pattern in the first dielectric and the second main circuit having a pattern in the main circuit 1 is integrally constitute a noise filter circuit having the function of an inductor and a capacitor function.

Here, the first main circuit conductor and the second main circuit conductor are formed by solder plating in advance, and the solder-plated first main circuit conductor and the second main circuit conductor are soldered on a coil pattern made of the conductive paste. Can be bonded.

By laminating the solder-plated first main circuit conductor and the second main circuit conductor, respectively, it can be formed to a thickness having a desired cross-sectional area.

A plurality of noise filter circuits are prepared, and a split core in which the plurality of filter circuits are housed, and a resin material for sealing the gaps in the split core, are constituted as a plurality of filter units having a function of an inductor and a capacitor. do.

The resin material may be made of a polymer resin material filled with an inorganic filler at a predetermined ratio.

The resin material may be made of silicone gel, and only the region on the side where the input and output terminals are disposed may be sealed with a polymer resin material filled with an inorganic filler at a predetermined ratio, and the other inner region may be sealed using the silicone gel. .

The resin material is made of silicone gel, and a cover for fixing the input / output terminals may be provided in an area on the side where the input / output terminals are arranged.

In addition, the present invention connects the noise filter to an input terminal and / or an output terminal of a power converter including a switch element, and filters the switching noise generated in accordance with the switching operation of the switch element to form a power converter.

In addition, the present invention connects the noise filter to a circuit in a power converter including a switch element, and filters the switching noise generated in accordance with the switching operation of the switch element to form a power converter.

In addition, the present invention is a step of forming a helical coil pattern made of an electrically conductive paste facing each other on both sides of the first dielectric sheet of the flat plate, and the coil pattern formed on one side of the first dielectric sheet Bonding a first main circuit conductor press-punched into the same shape as the coil pattern and having a cross-sectional area for energizing a desired current value thereon, to form a first main circuit pattern; and a side opposite to the first main circuit pattern Bonding a first ground line for inducing a current based on noise flowing into the coil pattern through the first dielectric sheet from the first main circuit pattern to the ground; Opposing the opposite sides of the sheet to form a spiral coil pattern made of a conductive paste, having the function of an inductor And a second main circuit pattern by bonding a second main circuit conductor press-punched into the same shape as the coil pattern and having a cross-sectional area for flowing a desired current value on the coil pattern formed on one side of the second dielectric sheet. And a current based on noise flowing from the second main circuit pattern into the coil pattern through the second dielectric sheet to the coil pattern formed on a side opposite to the second main circuit pattern to the ground. Bonding a guided second ground line, and inserting a flat insulating sheet between the first dielectric having the first main circuit pattern and the second dielectric having the second main circuit pattern; Using the other end which is not connected by connecting one end of the first main circuit conductor and one end of the second main circuit conductor as an input / output terminal, Provided is a method of manufacturing a noise filter in which the first dielectric having the first main circuit pattern and the second dielectric having the second main circuit pattern are integrated to form a noise filter circuit having the function and function of an inductor. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

A first embodiment of the present invention will be described with reference to Figs. 1A to 6D. First, the manufacturing method of the noise filter which concerns on this invention is demonstrated with reference to FIG.1 (a)-(d) -3.

In step 1 of FIG. 1A, 1 is a dielectric sheet. The dielectric sheet 1 is made of a ceramic material of ferroelectric such as BaTiO ₃ or PZT. The thickness of the dielectric sheet 1 is in the range of 100 µm to 1 mm, and in this example, a thickness of 0.5 mm is used.

Then, on both surfaces of the dielectric sheet 1, both surfaces of the dielectric sheet 1 are formed with a conductive paste, and the spiral coil patterns 2a and 2b each having a function of an inductor are formed to face each other. As this conductive paste, for example, a paste containing Ag as a main component can be used. Although the pattern formation method in this process can be performed by apply | coating and hardening | curing an electrically conductive paste by screen printing, it is also possible to form copper etc. in a pattern by the sputtering method, the vacuum vapor deposition method, or the plating method.

Next, in step 2 of FIG. 1B, the punching coil 3a having the same shape as the coil pattern 2a (that is, on the coil pattern 2a formed on one surface of the dielectric sheet 1) The first main circuit conductor) is joined by soldering. By this junction, the 1st main circuit pattern 4a which functions as an inductor and a capacitor | condenser is comprised.

This punching coil 3a has a cross-sectional area necessary for flowing current of a main circuit (for example, a circuit of a power converter), and is molded by, for example, press punching from a copper plate. In this case, for example, it is possible to take the size of the cross-sectional area necessary for flowing the current capacity of about 1 to several tens A, and the film thickness can be formed in the range of 0.5 to 1.0 mm.

Further, in order to connect with an external circuit, one end of the punching coil 3a is formed with a region drawn out by a certain length on the outside so as to be inserted by mounting a pin on a printed wiring board, for example. In this example, one end of the punching coil 3a is U _l .

As shown in Fig. 4, the inner end where the punching coil 3 is wound and the dielectric sheet 1 positioned below the end are pinned to each other to obtain the number of turns of the coil and when different patterns are stacked. The through hole 7 is formed in advance in order to be connected with each other.

Next, in step 3 in FIG. 1C, the current of the noise component is applied to the coil pattern 2b formed on the side opposite to the surface on which the first main circuit pattern 4a of the dielectric sheet 1 is formed. The lead wire 2c for the ground pattern for flowing through is joined by soldering. The current of the noise component herein refers to a current due to the noise component that flows into the coil pattern 2b through the dielectric sheet 1 through which the current flowing in the first main circuit pattern 4a flows.

By the above processes 1 to 3, the first main circuit pattern 4a having U ₁ is formed on one surface of the dielectric sheet 1, and the coil pattern 2b having the lead wire 2c on the other surface. A substrate A having the function of an inductor and a capacitor having a structure) can be manufactured.

Here, the board | substrate B which has the same structure as the said board | substrate A is produced. In this case, the board | substrate B is comprised by forming the 2nd main circuit pattern 4b in one surface of the dielectric sheet 5, and forming the coil pattern 2b in the other surface. The coil 3b (that is, the second main circuit conductor) of the second main circuit pattern 4b has a region drawn out by a predetermined length on the outside, and one end of the region is U ₂ . The board | substrate B comprised in this way has a function of an inductor and a capacitor similarly to the board | substrate A. As shown in FIG.

Next, in step 4 in FIG. 1D, the substrate A on which the first main circuit pattern 4a is formed on the dielectric sheet 1 and the second main circuit pattern on the dielectric sheet 5 are formed. The board | substrate B in which 4b was formed is connected through the interlayer insulation sheet 6. The interlayer insulating sheet 6 is provided with the through holes 7 as in the substrates A and B. Thus, the boards A and B are integrally formed by inserting a pin into the through holes 7 and fixing them with solder. You can do In addition, by increasing the number of substrates, the number of turns of the coil can be increased.

By fixing with pins in this manner, one end of the inner side of the first main circuit pattern 4a and one end of the inner side of the second main circuit pattern 4b are electrically connected, and the first main circuit pattern 4a and the second winding The furnace pattern 4b is connected in series. As a result, one end U ₁ drawn to the outside of the first main circuit pattern 4a and one end U ₂ drawn to the outside of the second main circuit pattern 4b can be used as an electrical input / output terminal.

The coil patterns 2b for grounding the substrates A and B are the coil patterns 2a for the main circuit (corresponding to the first main circuit pattern 4a and the second main circuit pattern 4b). Similarly, the connection is made using a through hole (not shown). In this embodiment, the connected ground terminal is set to P. FIG. Moreover, the through-hole position of the coil pattern 2a for main circuits, and the through-hole position of the coil pattern 2b for ground circuits are formed in the position which deviated so that it may not mutually overlap.

By the above process 1 to process 4, the 2nd main circuit pattern 4b on the board | substrate A in which the 1st main circuit pattern 4a was formed on the 1st dielectric material 1, and the 2nd dielectric material 5 was carried out. The board | substrate B in which () was formed is integrated, and the set of the noise filter circuit 100 which has a function of an inductor and a capacitor can be comprised. In this case, by connecting one end of the first main circuit pattern 4a and one end of the second main circuit pattern 4b, one end of the unconnected side can be used as the input terminal U ₁ and the output terminal U ₂ . Can be.

Next, in step 5 of FIG. 2, two sets of noise filter circuits prepared in step 1 to step 4 are prepared. In this case, in response to the combination of the input and output terminals of the first layer of the noise filter circuit 100 to U _l, U _2, and the input and output terminals of the second tier noise filter circuit 200 to a V _l, V _2. And the insulating sheet 8 is arrange | positioned between the 1st-layer noise filter circuit 100 and the 2nd-layer noise filter circuit 200, and these laminated circuits were sandwiched using the magnetic substance division core 9 in the up-down direction. Put it in. Thus, the two sets of noise filter circuits 100 and 200 are housed in one case.

In addition, the magnetic dividing core 9 has a structure in which openings 9a are formed at one side in order to take out the lead wires of the input / output terminals U ₁ and U ₂ and the input / output terminals V ₁ and V ₂ to the outside. As a material of the magnetic body split core 9, for example, a ferrite core can be used. Moreover, the projection part 9b for positioning and fixation is formed in the center part in the magnetic body dividing core 9. As shown in FIG.

If the number of noise filter circuits to be inserted into the magnetic body split core 9 is two sets, a single-phase and three sets of three-phase filters are formed by combining a common mode reactor and a ground capacitor used in the line filter. can do.

Next, in step 6 of FIG. 3, the polymer resin material 10 is removed from the opening 9a of the magnetic body dividing core 9 in which the two sets (single phase) of the noise filter circuits 100 and 200 are accommodated. Inflows to solidify. Thus, by mounting, the opening (9a) has input and output terminals of the pattern in the first main circuit of the noise filter circuit (100) (U _l, U _2), and a second to the pattern input-output terminal 2, the main circuit of the noise filter circuit 200 Two-phase lead terminals of (V _l , V ₂ ) are drawn out. These protruding lead terminals can be solder-bonded in the form of pin insertion or surface mounting of a socket of a printed wiring board, and thus can be handled as one mounting component integrated with a substrate.

Next, the electrical properties of the substrate structure will be described with reference to FIGS. 5 and 6. In Fig. 5, the first main circuit pattern 4a as a conductor for an inductor has a cross-sectional area as large as possible to allow current of the main circuit of a power converter (not shown) to flow. The first main circuit pattern 4a is composed of a coil pattern 2a made of a conductive paste provided on the dielectric sheet 1 and a punching coil 3a made of a conductor. The coil pattern 2b as the grounding conductor is formed at a position facing the first main circuit pattern 4a via the dielectric sheet 1.

Since the coil pattern 2b, which is a grounding conductor, may only induce a current of a noise component flowing through the dielectric sheet 1 to ground, its cross-sectional area can be made smaller than that of the first main circuit pattern 4a. . In addition, since the board | substrate structure of the 2nd main circuit pattern 4b is also the same, the description is abbreviate | omitted.

6, the terminal of the pattern (4a) to the inductor conductor for the first main circuit (U _l, U ₂₎ is because they have a predetermined length, the minute inductance is continuously distributed. Similarly, minute inductance is continuously distributed also in the coil pattern 2b which is a grounding conductor connected to the terminal P. As shown in FIG. Further, since the first main circuit pattern 4a and the coil pattern 2b face each other through the dielectric sheet 1, minute capacitances are continuously formed between the respective conductors, and as a result, a low pass filter A distributed constant circuit having the function of The low pass filter referred to herein has a cutoff frequency (for example, 150 Hz or more) necessary for filtering switching noise generated in accordance with switching operations of semiconductor switch elements constituting a power converter such as an inverter.

Next, a second embodiment of the present invention will be described with reference to FIGS. 7 and 8.

FIG. 7: shows sectional drawing at the time of performing the solder plating 11 to the surface of the punching coil 3a, 3b which comprises the 1st main circuit pattern 4a and the 2nd main circuit pattern 4b. As the solder plating 1l, materials such as Sn / Pb and Sn / Ag are used. By performing solder plating in advance in this manner, soldering can be easily performed on the coil pattern 2a formed of the conductive paste in the above step 2.

8 shows an example in which the punching coils 3a on which the solder plating l1 has been applied are laminated in two layers and joined. By laminating the punching coils 3a in this manner, it becomes possible to increase the current capacity for passing through. Moreover, three or more layers can also be laminated | stacked.

Next, a third embodiment of the present invention will be described with reference to FIG.

FIG. 9 shows a structure in the case where two sets of noise filter circuits 100 and 200 are housed in the magnetic body dividing core 9. In this example, the magnetic body dividing core 9 and the noise filter circuits 100 and 200 are sealed using a polymer resin material 10 different from the example of FIG. 3 above.

As the polymer resin material 10, epoxy resin, urethane resin, or the like to which inorganic fillers such as quartz powder or alumina powder are added are used. In addition, making the thermal expansion coefficient of the polymer resin material l0 equal to that of the magnetic body dividing core 9 does not cause deformation due to thermal stress.

By sealing using the polymer resin material 10 made of such a material, the insulation characteristic can be improved, and contamination by dust or the like from the opening 9a to the inside can be protected and insulation deterioration can be prevented. .

In addition, by adding the filler to the polymer resin material 10, it is possible to dissipate heat generated by the flow. Further, the lead terminals U ₁ and U _{2 of} the first main circuit pattern 4a and the lead terminals V ₁ and V _{2 of} the second main circuit pattern 4b are formed of a polymer resin material ( By fixing by 10), even if an external force is applied to the terminals U ₁ , U ₂ , V ₁ , V ₂ , it is possible to prevent the external force from being applied to the internal noise filter circuits 100, 200.

Next, a fourth embodiment of the present invention will be described with reference to FIG.

FIG. 10 shows the structure in the case where two sets of noise filter circuits 100 and 200 are housed in the magnetic body dividing core 9. In this example, first, the silicon gel 11 is sealed to the vicinity of the opening 9a between the magnetic body split core 9 and the noise filter circuits l00 and 200, and a polymer is formed on the upper part of the silicone gel 11. The resin material 10 is sealed. As the polymer resin material 10, various materials as described above can be used.

Thus, by appropriately selecting a material to be sealed at the inside and the surface of the case, it is possible to improve the insulation characteristics, to prevent contamination by dust or the like from the opening 9a to the inside, and to prevent insulation deterioration. .

In addition, by using the silicone gel 11 having a small elastic force, since deformation due to thermal stress does not occur, mechanical reliability can be obtained. In addition, since the lead terminals U ₁ and U _{2 of} the first main circuit pattern 4a and the lead terminals V ₁ and V _{2 of} the second main circuit pattern 4b are fixed with the polymer resin material 10. Even if an external force is applied to these lead terminals U ₁ and U ₂ and lead terminals V ₁ and V ₂ , it is possible to prevent the external force from being applied to the internal noise filter circuits 100 and 200.

Next, a fifth embodiment of the present invention will be described with reference to FIG.

FIG. 11 shows the structure in the case where two sets of noise filter circuits 00 and 200 are housed in the magnetic body dividing core 9. In this example, first, the silicon gel 11 is sealed to the vicinity of the opening 9a between the magnetic dividing core 9 and the noise filter circuits 100 and 200, and the opening 9a is covered with the terminal fixing cover 12. The lead terminals U ₁ and U _{2 of} the first main circuit pattern 4a and the lead terminals V ₁ and V _{2 of} the second main circuit pattern 4b are fixed by overwriting with.

By using the terminal fixing cover 12 in this manner, even if an external force is applied to these lead terminals U _l and U ₂ and lead terminals V _l and V ₂ , the internal noise filter circuits 100 and 200 are applied. External force can be prevented. In addition, contamination by dust or the like from the opening portion 9a to the inside can be protected, and insulation deterioration can be prevented. The material for the terminal fixing cover 12 may be a polymer resin material such as PPS (polyphenylene sulfide) and PBT (polybutylene terephthalate), which are easily molded.

Next, a sixth embodiment of the present invention will be described with reference to Figs.

12 shows an example in which a noise filter according to the present invention is provided at an input terminal of a power converter 20 such as an inverter. Here, three sets (three phases) of noise filter circuits 100, 200, and 300 were used.

In the example of FIGS. 1A to 1D described above, the structure in the case where single phase noise filter circuits 100 and 200 are accommodated in the magnetic body split core 9 is constituted as three phase portions. In this case, in the step 5 of FIG. 2, the noise filter circuit 300 is further added to the lower part of the noise filter circuit 200 to be mounted.

The lead terminal of the noise filter circuit 100 configured as described above is U ₁ , U ₂ , the lead terminal of the noise filter circuit 200 is V _l , V ₂ , and the lead terminal of the noise filter circuit 300 is W. _{Let 1} and W ₂ be set. Then, the lead terminals U ₁ , V ₁ , W _{1 are} connected to the terminals 2la, 2lb, 21c of the external circuit, and the lead terminals U ₂ , V ₂ , W ₂ are connected to the power converter 20. do.

By connecting in this way, the low frequency noise which intrudes with a signal from the terminals 21a, 21b, and 2lc to the power converter 20 can be filtered, and the switching noise which is generated by the element in the power converter 20 is received by the terminal 21a. , 2lb, 21c) can be prevented.

Next, FIG. 13 shows an example in which three sets (three phases) of noise filter circuits 100, 200, and 300 according to the present invention are provided at an output terminal of a power converter 20 such as an inverter.

The lead terminals U ₁ , V ₁ , W ₁ are connected to the power converter 20, and the lead terminals U ₂ , V ₂ , W ₂ are connected to the terminals 22a, 22b, 22c of the external circuit.

By connecting in this way, it is possible to filter the switching noise generated by the elements in the power converter 20 and the like, thereby preventing the switching noise from being transmitted from the power converter 20 to the terminals 22a, 22b, 22c. have. In addition, low frequency noise intruding into the power converter 20 from the terminals 22a, 22b, and 22c can be filtered out.

Next, FIG. 14 shows an example in which two sets of noise filter circuits 00 and 200 according to the present invention are provided inside a power converter 20 such as an inverter.

In the power converter 20, a rectifier 23 for converting an AC input from the outside into a direct current is provided on the input side, and a semiconductor switch element 24 is provided on the output side.

The lead terminals U ₁ and V ₁ are connected to the rectifier 23 at the input terminal, and the lead terminals U ₂ and V ₂ are connected to the semiconductor switch element 24 on the output side.

By connecting in this way, switching noise which arises in accordance with the switching operation of the semiconductor switch element 24 which comprises the power converter 20 can be filtered out.

As described above, according to the present invention, a conductor pattern having a function of a helical inductor made of a conductive paste is disposed opposite to both sides of the dielectric sheet, and the current of the main circuit such as a power converter flows on the other conductor pattern. The main circuit pattern is formed by joining the press-punched conductors in the same shape as the conductor pattern with the cross-sectional area that can be made, and the current based on the noise flowing from the main circuit pattern to the other conductor pattern through the dielectric sheet. By inducing the ground to the filter circuit having the inductor function and the condenser function, it is possible to sufficiently prevent low frequency noise such as switching noise of the power converter and to provide a noise filter capable of sufficiently securing a current of several amperes or more necessary for power conversion. can do.

Further, according to the present invention, since the plurality of noise filters are accommodated in the magnetic dividing core, the gaps are sealed with a polymer resin material, so that the production can be performed by a simple manufacturing process, thereby making it easy to mount the printed wiring board. At the same time, it is possible to provide a noise filter with excellent insulation, mechanical reliability, and compactness.

1 (a) to 1 (d) are process drawings showing a method for manufacturing a noise filter as a first embodiment of the present invention.

FIG. 2 is a process chart showing a method of manufacturing a noise filter subsequent to FIGS. 1A to 1D.

3 is a process chart showing a method of manufacturing a noise filter subsequent to FIG. 2.

4 is a perspective view showing a shape of a through hole provided at one end of a punching coil;

5 is a perspective view showing a basic structure of a noise filter.

6 is a circuit diagram showing a distributed constant circuit of LC.

Fig. 7 is a sectional view showing the structure of a solder plated punching coil as a second embodiment of the present invention.

8 is a cross-sectional view showing a structure in which a punching coil is laminated.

Fig. 9 is a sectional view showing the structure when the noise filter is accommodated in the case as the third embodiment of the present invention.

Fig. 10 is a sectional view showing the structure in the case of storing a noise filter in a case as a fourth embodiment of the present invention.

Fig. 11 is a sectional view showing a structure when the noise filter is stored in a case as a fifth embodiment of the present invention.

Fig. 12 is a block diagram showing a configuration in the case where a three-phase noise filter is connected to an input terminal of a power converter as a sixth embodiment of the present invention.

Fig. 13 is a block diagram showing the configuration when a three-phase noise filter is connected to an output terminal of a power converter.

Fig. 14 is a block diagram showing the configuration when a noise filter is connected to a power converter.

<Explanation of symbols for main parts of drawing>

1: first dielectric sheet

2a, 2b: coil pattern

2c: first ground wire

2d: second ground wire

3a: first main circuit conductor

3b: second main circuit conductor

4a: first main circuit pattern

4b: second main circuit pattern

5: second dielectric sheet

6: insulation sheet

9: ferrite split core

10: resin material (polymer resin material)

U _l , U ₂ , V _l , V ₂ , W _l , W ₂ : I / O terminals

Claims (16)

A first flat dielectric sheet; A spiral coil pattern formed opposite to both sides of the first dielectric sheet, having a function of an inductor, and formed of a conductive paste; A first main circuit pattern formed by bonding a first main circuit conductor press-punched into the same shape as the coil pattern and having a cross-sectional area through which a desired current value flows on the coil pattern formed on one side of the first dielectric sheet and; A first bonded to the coil pattern formed on a side opposite to the first main circuit pattern, and inducing a current based on noise flowing into the coil pattern from the first main circuit pattern through the first dielectric sheet to ground; A ground wire; A second planar dielectric sheet; A spiral coil pattern formed opposite to both sides of the second dielectric sheet, having a function of an inductor, and formed of a conductive paste; A second main circuit pattern formed by bonding a second main circuit conductor press-punched into the same shape as the coil pattern and having a cross-sectional area through which a desired current value flows on the coil pattern formed on one side of the second dielectric sheet; and; A current bonded to the coil pattern formed on a side opposite to the second main circuit pattern, for inducing a current based on noise flowing from the second main circuit pattern into the coil pattern through the second dielectric sheet to the ground; 2 ground wires; A flat insulating sheet inserted between the first dielectric having the first main circuit pattern and the second dielectric having the second main circuit pattern And By connecting one end of the first main circuit conductor and one end of the second main circuit conductor, the other end which is not connected is used as an input / output terminal, And the first dielectric having the first main circuit pattern and the second dielectric having the second main circuit pattern are integrated to form a filter circuit having a function of an inductor and a capacitor. The method of claim 1, wherein the first main circuit conductor and the second main circuit conductor are configured by solder plating in advance, And soldering the solder-plated first main circuit conductor and the second main circuit conductor onto a coil pattern made of the conductive paste. The noise filter according to claim 2, wherein the first main circuit conductor and the second main circuit conductor, which are solder plated, are laminated respectively to form a desired cross-sectional thickness. The filter circuit according to any one of claims 1 to 3, wherein a plurality of filter circuits are prepared, A noise filter comprising a split core in which the plurality of filter circuits are housed, and a resin material for sealing the gaps in the split core, as a plurality of filter units having a function of an inductor and a capacitor. The noise filter according to claim 4, wherein the resin material is made of a polymer resin material filled with an inorganic filler at a predetermined ratio. The resin material according to claim 4, wherein the resin material is made of a silicone gel, and only the region on the side where the input / output terminals are disposed is sealed with a polymer resin material filled with an inorganic filler at a predetermined ratio, and the other inner region covers the silicone gel. Noise filter, characterized in that the sealing using. The noise filter according to claim 4, wherein the resin material is made of silicone gel, and a cover for fixing the input / output terminals is provided in a region on the side where the input / output terminals are arranged. A noise filter according to any one of claims 1 to 7 is connected to an input terminal and / or an output terminal of a power converter having a switch element, and to filter switching noise generated in accordance with the switching operation of the switch element. A power converter, characterized in that. The noise filter of any one of Claims 1-7 is connected to the circuit in the power converter provided with a switch element, and the switching noise which generate | occur | produces according to the switching operation of the said switch element is characterized by the above-mentioned. Power converter. Forming a helical coil pattern formed on both sides of the flat plate-like first dielectric sheet so as to face a spiral coil pattern made of a conductive paste, having a function of an inductor; A first main circuit pattern is formed by bonding a first main circuit conductor press-punched into the same shape as the coil pattern and having a cross-sectional area through which a desired current value flows on the coil pattern formed on one side of the first dielectric sheet. Process of doing; A first ground line for inducing a current based on noise flowing from the first main circuit pattern into the coil pattern through the first dielectric sheet to a ground in the coil pattern formed on a side opposite to the first main circuit pattern; Bonding step; Forming a spiral coil pattern made of a conductive paste and having an inductor function opposite to both sides of the second flat sheet of dielectric material; On the coil pattern formed on one side of the second dielectric sheet, a second main circuit pattern is formed by bonding a second main circuit conductor press-punched into the same shape as the coil pattern and having a cross-sectional area for flowing a desired current value. To process; A second ground line for inducing a current based on noise flowing from the second main circuit pattern into the coil pattern through the second dielectric sheet to the ground in the coil pattern formed on a side opposite to the second main circuit pattern; Bonding step; Inserting a flat insulating sheet between the first dielectric having the first main circuit pattern and the second dielectric having the second main circuit pattern Including, By connecting one end of the first main circuit conductor and one end of the second main circuit conductor, the other end which is not connected is used as an input / output terminal, The first dielectric having the first main circuit pattern and the second dielectric having the second main circuit pattern are integrated to form a filter circuit having a function of an inductor and a capacitor. Manufacturing method. The method of claim 10, further comprising: soldering the first main circuit conductor and the second main circuit conductor; And soldering the solder-plated first main circuit conductor and second main circuit conductor onto a coil pattern made of the conductive paste. 12. The method of manufacturing a noise filter according to claim 11, wherein the soldered plated first main circuit conductor and the second main circuit conductor are laminated to form a desired cross-sectional area, respectively. The filter circuit according to any one of claims 10 to 12, wherein a plurality of filter circuits are prepared, Storing the plurality of filter circuits in a split core; Sealing a gap between the divided cores with a resin material; A method of manufacturing a noise filter, comprising a plurality of filter units having a function of an inductor and a capacitor. The method of manufacturing a noise filter according to claim 13, wherein the resin material is made of a polymer resin material filled with an inorganic filler at a predetermined ratio. The method of claim 13, wherein the resin material is made of a silicone gel, and only the region on the side where the input and output terminals are disposed is sealed with a polymer resin material filled with an inorganic filler at a predetermined ratio, and the other inner region is used to seal the silicone gel. Sealing using, The manufacturing method of the noise filter characterized by the above-mentioned. The method of manufacturing a noise filter according to claim 13, wherein the resin material is made of silicone gel, and a cover for fixing the input / output terminals is provided in a region on the side where the input / output terminals are arranged.