JP2018038131A - Power converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power converter capable of reducing noise generated between the DC bus and DC reactor of the power converter, regardless of arrangement of the DC reactor or the means for adjusting the cable length.SOLUTION: In a power converter including an AC/DC conversion unit 210 where AC power is converted into DC power by semiconductor rectifier elements, a DC/AC conversion unit 230 for converting a DC power outputted from the AC/DC conversion unit 210 into an AC power by switching operation of semiconductor switching elements, and a DC reactor 221 to be connected in series with a DC bus between these conversion units 210, 230, common mode noise reduction means 10, consisting of a common mode reactor or capacitor, resistor, and the like, is provided between the opposite ends of the DC reactor 221 and the terminals P, Pon the DC bus side.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a technique for suppressing electromagnetic noise generated by a switching operation of a semiconductor switching element constituting a power conversion device.

For example, an inverter shown in FIG. 10 is known as a power converter.
This inverter is configured to convert the three-phase AC power supplied from the three-phase AC power source 100 into AC / DC / AC conversion by the main circuit unit 200 and to supply the three-phase motor 300.

  That is, the main circuit unit 200 includes an AC / DC conversion unit (rectification unit) 210 formed of a diode bridge, a DC / AC conversion unit 230 formed of a bridge circuit of a semiconductor switching element in which freewheeling diodes are connected in antiparallel, and a DC intermediate circuit. And a smoothing capacitor 220 connected to the power supply 100, and an AC / DC converter 210, a smoothing capacitor 220, and a DC / AC converter 230 are connected in parallel in this order from the power supply 100 side.

  The input terminals R, S, and T of each phase of the AC / DC converter 210 are connected to the corresponding phases of the three-phase AC power supply 100 via the input cable 400, respectively, and the output terminals U of each phase of the DC / AC converter 230. , V, W are connected to the terminals of the three-phase motor 300 via the output cable 500, respectively.

  The input cable 400 and the output cable 500 include ground wires 401 and 501, respectively. The main circuit unit 200 and the motor 300 are connected to a common ground potential by the ground wires 401 and 501, respectively. The method for grounding the main circuit unit 200 and the motor 300 is not limited to the illustrated example.

  Here, since a sine wave AC voltage is applied to the AC / DC converter 210 from the power supply 100, the reverse current blocking operation of the diode has a frequency of about 3 to 25 times the power frequency (fundamental wave). Distorted current including harmonics is generated. When this current flows to the power supply 100 side, the power supply voltage waveform is distorted and a failure such as damage to a power factor improving capacitor and a transformer (not shown) is generated.

For this reason, measures are taken to maintain the power supply quality in accordance with the above-described regulations for suppressing harmonics, and a method using a DC reactor is widely used as this measure.
That is, as shown in FIG. 10, harmonics can be suppressed by connecting the DC reactor 221 to the terminals P ₁ and P ₂ on the DC bus between the AC / DC converter 210 and the smoothing capacitor 220. .

  By the way, when the switching element operates, noise is generated because a high frequency component is included in the output voltage and output current of the switching element. This noise component causes conduction noise that is conducted to the power supply and load via the cable and radiation noise that propagates through the space. In addition, these noises are electrostatically coupled and inductively coupled to the adjacent wiring. It causes problems such as malfunction.

Therefore, various methods have been proposed to reduce noise caused by the operation of the switching element.
For example, FIG. 11 is a circuit configuration diagram of the power conversion device described in Patent Document 1. In this prior art, a so-called common mode noise current is reduced by inserting a noise filter 510 formed of a choke coil or a transformer into an output cable 500 between the main circuit unit 200 of the inverter and the motor 300. As is well known, the common mode noise current is a current that flows into the ground side via a stray capacitance of a power cable or a motor, and causes conduction noise or radiation noise.

JP 2001-231268 A (paragraphs [0025] to [0049], FIG. 1, etc.)

As described above, common mode noise countermeasures for power cables including input / output cables are widely used.
However, as shown in FIG. 10, it is known that when a DC reactor is connected to the DC bus of the main circuit section of the inverter and noise countermeasures are taken, high level noise is generated from the connection section of the DC reactor. This kind of noise countermeasure is still not enough.

  For example, FIG. 12 is a conceptual diagram of a panel on which the main circuit unit 200, the control electronic device 240, the switch 250, the DC reactor 221 and a power input filter (not shown) are mounted. Reference numeral 260 denotes a board casing, and reference numeral 261 denotes a wiring duct.

In FIG. 12, the result of measuring the common mode noise in the MHz band at two locations of the DC reactor cable 222 connecting the main circuit unit 200 and the DC reactor 221 and the input cable 400 of the main circuit unit 200 is shown in FIG. Shown in
According to FIG. 13, the noise level due to the input cable 400 is high in the frequency band of 7 [MHz] or lower, but the noise level due to the DC reactor cable 222 is higher in the frequency band higher than that.

FIG. 14 shows the state of the electronic device cable 241 in a state in which the DC reactor cable 222 and the electronic device cable 241 in FIG. 12 are close to each other and in a state in which both cables are separated from each other by several [cm]. A measurement example of the common mode noise level is shown.
According to FIG. 14, when both cables 222 and 241 are close to each other as compared with the case where both cables 222 and 241 are separated, noise is increased in a region of about 7 [MHz] to 20 [MHz]. It can be seen that noise from the DC reactor cable 222 is superimposed on the electronic device cable 241.

  In order to solve such a problem of noise superposition, the distance between the DC reactor cable 222 and the electronic device cable 241 is increased, or the DC reactor 221 is arranged as close to the main circuit unit 200 as possible. Measures such as shortening can be considered. However, there are cases where it is difficult to take these measures because of restrictions on the layout of each part and restrictions on the external shape of the apparatus.

  Therefore, the problem to be solved by the present invention is that it is possible to reduce the noise generated from the connection portion of the DC reactor to the DC bus of the power converter without using the means such as the arrangement of the DC reactor and the adjustment of the cable length. It is to provide a conversion device.

In order to solve the above-mentioned problem, the invention according to claim 1 is directed to a first converter that converts AC power into DC power by a semiconductor rectifier, and DC power output from the first converter is switched by a semiconductor switching element. In a power converter comprising: a second converter that converts AC power or DC power by operation; and a DC reactor connected in series to a DC bus between the first converter and the second converter. ,
Common mode noise reduction means is provided between both ends of the DC reactor and the DC bus.

  According to a second aspect of the present invention, in the power conversion device according to the first aspect, the DC bus includes first and second terminals, and the first and second terminals are connected to the common mode noise reducing means. And connected to both ends of the DC reactor.

  According to a third aspect of the present invention, in the power conversion device according to the first aspect, the first and second terminals connected to the DC bus via the common mode noise reducing means are connected to both ends of the DC reactor. It is characterized by being connected to each other.

  The invention according to claim 4 is the power conversion device according to any one of claims 1 to 3, wherein the common mode noise reduction means is a common mode reactor.

  The invention according to claim 5 is the power conversion device according to any one of claims 1 to 3, wherein the common mode noise reduction means includes at least a capacitor.

  The invention according to claim 6 is the power conversion device according to claim 1 or 2, wherein the common mode noise reduction means has a shield for connecting between both ends of the DC reactor and the DC bus. It is a cable.

  The invention according to claim 7 is the power conversion device according to claim 6, wherein a part of the shielded cable is accommodated in a wiring duct.

  The invention according to claim 8 is the power converter according to claim 6 or 7, wherein the shield portion of the shielded cable is connected to a ground conductor plate of the power converter.

ADVANTAGE OF THE INVENTION According to this invention, the common mode noise in the connection part of the direct-current bus of a power converter and direct-current reactor which becomes large noise generation reduction in a high frequency band can be suppressed by a noise reduction means.
As a result, conduction noise and radiation noise caused by common mode noise can be reduced, and adverse effects on the power supply and peripheral devices can be removed to improve the reliability of the power conversion device.

It is a circuit block diagram which shows 1st Embodiment of this invention. It is a circuit block diagram of the principal part of Example 1 which concerns on 1st Embodiment of this invention. It is a circuit block diagram of the principal part of Example 2 which concerns on 1st Embodiment of this invention. It is a circuit block diagram of the principal part of Example 3 which concerns on 1st Embodiment of this invention. In 1st Embodiment of this invention, it is the figure which showed the common mode noise level of the cable for electronic devices according to the space | interval with the cable for DC reactors compared with the prior art. It is a circuit block diagram of the principal part of Example 4 which concerns on 2nd Embodiment of this invention. It is a block diagram of the principal part of Example 5 which concerns on 3rd Embodiment of this invention. It is a circuit block diagram of the principal part of Example 6 which concerns on 4th Embodiment of this invention. It is a block diagram of the principal part of Example 7 which concerns on 5th Embodiment of this invention. It is a circuit block diagram of a general inverter. It is a circuit block diagram of the prior art described in patent document 1. FIG. It is a conceptual diagram of the board provided with the main circuit part of an inverter, a DC reactor, etc. It is a figure which shows the common mode noise level of the cable for DC reactors, and the input cable of the main circuit part. It is a figure which shows the common mode noise level of the cable for electronic devices according to the space | interval with the cable for DC reactors.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts as those in FIG.

  FIG. 1 is a circuit configuration diagram of a power conversion device according to the first embodiment of the present invention. This first embodiment is different from FIG. 10 in that common mode noise reduction means (hereinafter also simply referred to as noise reduction means) 10 is connected between the DC bus of the inverter main circuit section 200 and the DC reactor 221. It is in. The AC / DC converter 210 constituting the main circuit unit 200 corresponds to a first converter in the claims, and the DC / AC converter 230 corresponds to a second converter.

In FIG. 1, first and second terminals P ₁ and P ₂ are provided on the positive potential side (high voltage side) of the DC bus of the main circuit unit 200, and these terminals P ₁ and P ₂ include The DC reactor 221 is connected via the DC reactor cable 222 and the noise reduction means 10.

As for the arrangement of the noise reduction means 10, an appropriate position may be selected according to the device configuration, and there is no particular limitation. However, from the viewpoint of reducing noise, it is preferably in the vicinity of the main circuit unit 200. This is because when the switching frequency is increased, the influence of the wiring length from the main circuit unit 200 to the noise reduction unit 10 cannot be ignored, and noise in the switching frequency band is conducted from the switching element as the noise generation source to the noise reduction unit 10. It is.
Therefore, when the noise reduction means 10 is arranged in the vicinity of the main circuit unit 200, the portion where the noise in the frequency band is generated can be reduced, and the radiation noise can be reduced and the noise superimposed on the peripheral device can also be reduced. growing.

  Below, the specific structure of the noise reduction means 10 in 1st Embodiment is demonstrated as Example 1-Example 3. FIG.

FIG. 2 is a circuit configuration diagram illustrating a main part of the power conversion apparatus according to the first embodiment.
In this embodiment, the DC reactor cable 222 that connects the terminal P ₁ of the main circuit unit 200 and one end of the DC reactor 221, and the terminal P ₂ of the main circuit unit 200 that connects the other end of the DC reactor 221 are described above. Common mode noise is reduced by connecting the common mode reactor 10a between the terminals P ₁ and P ₂ and the DC reactor 221 so as to be in the common mode with the cable 222.

  The common mode reactor 10a has a low impedance characteristic in a frequency band (a few [kHz] or less as a guide) corresponding to a harmonic frequency of the DC reactor 221, which is equivalent to the harmonic countermeasure frequency of the DC reactor 221, and from the DC / AC converter 230. Noise having high impedance characteristics in the MHz band in which noise generated, particularly radiation noise is a problem, and in particular, those having a peak of impedance frequency characteristics in the tens to hundreds [MHz] band are preferable. .

FIG. 3 is a circuit configuration diagram illustrating a main part of the power conversion apparatus according to the second embodiment.
In this embodiment, a cable 222 that connects the terminal P ₁ of the main circuit unit 200 and one end of the DC reactor 221, and a cable 222 that connects the terminal P ₂ of the main circuit unit 200 and the other end of the DC reactor 221 are provided. The common mode noise is reduced by winding the magnetic core 10b constituting the common mode reactor so as to surround it.

In FIG. 3, one magnetic core 10b is wound once, but the number of magnetic cores and the number of turns are not particularly limited. The type, number, and number of windings of the magnetic core are determined by winding the magnetic core, as described above, corresponding to the harmonic countermeasure frequency of the DC reactor 221 (frequency range from commercial frequency to 25th harmonic) (reference) In the case of several [kHz] or less), the impedance characteristic is low, and noise generated from the DC / AC converter 230, particularly high noise characteristics in the MHz band in which radiation noise is a problem, more specifically, frequency characteristics of impedance It is preferable that the peak of is in the band of several tens [MHz] to several hundred [MHz].
As the magnetic core 10 b, for example, a hollow soft ferrite core made of Ni—Zn may be wound around a cable connecting the terminal P ₁ and one end of the DC reactor 221 twice.

4A to 4C are circuit configuration diagrams illustrating main parts of the power conversion device according to the third embodiment. The third embodiment includes at least a capacitor as noise reduction means.
First, the example of FIG. 4 (a), the terminal _{P 1} of the main circuit unit 200 and the cable 222 for connecting the one end of the DC reactor 221, the terminal _{P 2} of the inverter main circuit unit 200 and the other end of the DC reactor 221 Common mode noise is reduced by connecting the capacitor 10c between the cable 222 and the cable 222.

In FIG. 4A, one capacitor is connected, but a plurality of capacitors may be connected in series or in parallel. The type of the capacitor is a high impedance characteristic in a frequency band of commercial frequency to 25 times higher harmonic (corresponding to a few [kHz] or less as a guide), which corresponds to the harmonic countermeasure frequency of the DC reactor. Noise that is generated, especially those that have low impedance characteristics in the MHz band where radiation noise is a problem, more specifically, the impedance is selected to be lower than the characteristic impedance of the cable between the main circuit unit 200 and the DC reactor 221. It is preferable to do.
Moreover, it is preferable to select a capacitor with good high-frequency characteristics, and for example, a film capacitor or the like may be applied.

Further, as shown in FIGS. 4B and 4C, a resistor 10d may be connected in parallel or in series with the capacitor 10c. With such a configuration, it is possible to suppress unnecessary resonance caused by the capacitor 10c and a noise peak caused by the resonance.
As for the resistors in these cases, a plurality of resistors may be connected in parallel or in series as in the above-described capacitor.

Here, the function and effect of the first embodiment will be described.
FIG. 5 shows a circuit board for the electronic device according to the distance from the DC reactor cable 222 in the panel including the main circuit unit 200, the control electronic device 240, the DC reactor 221 and the like as shown in FIG. The common mode noise level of the cable 241 is shown, and “when the DC reactor cable is isolated” is a state in which the cables 222 and 241 are separated from each other by a few [cm].
FIG. 5A shows a conventional technique (substantially the same as FIG. 14 described above) that does not include the noise reducing means 10, and FIG. 5B shows the first embodiment (Examples 1 to 3). The case where the noise reduction means 10 is provided is shown.

As is apparent from FIGS. 5A and 5B, according to the present embodiment, even when the DC reactor cable 222 and the electronic device cable 241 are close to each other, the common mode noise level is the same for both cables 222. , 241 are not so different from the case where they are separated from each other, in particular, the noise level at about 7 [MHz] to 20 [MHz] is reduced.
For this reason, this embodiment is effective for suppressing the superimposition of noise from the DC reactor cable 222 to the electronic device cable 241. Further, since there is little need to consciously route both cables 222 and 241, there are few restrictions on the layout of the DC reactor 221, the electronic device 240, etc., and the DC reactor can be used even with various sizes of housings. 221, the electronic device 240, and the like can be accommodated in a desired position.

Next, a second embodiment of the present invention will be described.
The second embodiment is different from the first embodiment (Examples 1 to 3) in that the noise reduction means 10 is integrally arranged on the main circuit portion side of the inverter. Thus, by providing the noise reduction means 10 on the main circuit side, the noise reduction means 10 can be disposed in the vicinity of the switching element that is a noise source, and a further noise reduction effect can be obtained.
Hereinafter, Example 4 which concerns on 2nd Embodiment is demonstrated based on Fig.6 (a)-FIG.6 (e).

First, FIG. 6A is an example in which one end of the common mode reactor 10a is connected to the positive potential side of the DC bus of the main circuit part 200a of the inverter, and the other end is connected to the terminals P ₁ and P _2. . The DC reactor 221 may be connected via the cable from the terminals P ₁ and P _{2 in} FIG. 6A (the same applies to FIGS. 6B to 6E).
The method for selecting the impedance characteristics of the common mode reactor 10a is the same as in the first embodiment.

FIG. 6B is an example in which the positive potential side of the DC bus of the main circuit section 200b is connected to the terminals P ₁ and P ₂ through the magnetic core 10b constituting the common mode reactor. The shape, structure, and the like of the DC bus passing through the magnetic core 10b are not particularly limited, and may be a bus bar or a cable, for example. When the DC bus is a cable, the magnetic core may be wound a plurality of times. The selection of the number and type of magnetic cores is the same as in the second embodiment.

FIG. 6C shows an example in which a capacitor 10c is connected to the positive potential side of the DC bus of the main circuit unit 200c, and both ends of the capacitor 10c are connected to terminals P ₁ and P ₂ , respectively.
The connection position of the capacitor 10c is preferably close to the switching element that is a noise source so that the parasitic inductance component of the wiring from the capacitor 10c to the switching element is as small as possible, and the capacitor 10c is made of a conductor having a high frequency, low inductance, and a large surface area. And the switching element are more preferably connected. In FIG. 6C, one capacitor 10c is connected, but a plurality of capacitors may be connected in series or in parallel. The method for selecting a capacitor is the same as in the third embodiment.

  Further, a resistor 10d may be connected in parallel or in series with the capacitor 10c as in the main circuit portions 200d and 200e shown in FIG. 6D and FIG. 6E. Thereby, like FIG.4 (b), (c), the unnecessary resonance resulting from a capacitor | condenser and the peak of the noise which generate | occur | produces with this resonance can be suppressed. The number of resistors connected in parallel or in series with the capacitor 10c is not limited to one, and a plurality of resistors may be connected in parallel or in series.

Next, a third embodiment of the present invention will be described.
In the third embodiment, common mode noise reduction means is integrally connected to terminals P ₁ and P ₂ that are external terminals of a power semiconductor module that constitutes a main circuit portion of an inverter and to which a DC reactor 221 is connected. It is what.

As in the present embodiment, the noise reduction means is connected to the terminals P ₁ and P ₂ of the semiconductor module (FIG. 7 (a) is only between the terminals P ₁ and P ₂ and the terminals P ₁ ′ and P ₂ ′). If so, it can be arranged at a position closer to the switching element that is a noise source, and a higher noise suppression effect can be obtained. Further, since the noise reduction means is mounted on the semiconductor module, it is not necessary to provide this noise reduction means separately.
7A to 7E correspond to the symbols of the module internal circuit shown in FIG. 7F, respectively.
Hereinafter, Example 5 according to the third embodiment will be described with reference to FIGS. 7 (a) to 7 (e).

FIG. 7A shows an example in which a common mode reactor 10a is connected between terminals P ₁ and P ₂ and terminals P ₁ ′ and P ₂ ′ provided on the semiconductor module 205a. The selection of the frequency characteristics of the common mode reactor 10a is the same as in the second embodiment.
FIG. 7B shows an example in which the terminals P ₁ and P ₂ of the semiconductor module 205b are penetrated through the hollow magnetic core 10b constituting the common mode reactor. The selection of the number and type of magnetic cores is the same as in the second embodiment.

FIG. 7C shows an example in which a capacitor 10c is connected between terminals P ₁ and P ₂ provided on the semiconductor module 205c. Since the capacitor 10c is connected between the terminals P ₁ and P ₂ , the parasitic inductance component between the capacitor 10c and the switching element can be reduced, and good noise reduction characteristics can be obtained even at a high frequency. The type and characteristics of the capacitor 10c are the same as those in the third embodiment, and the number of capacitors 10c is not limited to the illustrated example.

  Further, a resistor 10d may be connected in parallel or in series with the capacitor 10c, as in the semiconductor modules 205d and 205e shown in FIG. 7D and FIG. 7E. If the noise reduction means is configured in this way, unnecessary resonance and noise peaks caused by the capacitor can be suppressed.

Next, a fourth embodiment of the present invention will be described. This embodiment is characterized in that a DC reactor component is configured by integrating various noise reduction means with the DC reactor 221.
If the noise reduction means is integrated with the DC reactor 221, connection work can be easily performed without requiring special work, and common mode noise countermeasure components are connected in the vicinity of the power converter or in the power converter. It is also applicable to cases where this is difficult. Hereinafter, Example 6 which concerns on this 4th Embodiment is demonstrated based on Fig.8 (a)-FIG.8 (e).

A DC reactor component 20a shown in FIG. 8A is an example in which a common mode reactor 10a is connected between both ends of a DC reactor 221 and terminals P ₁ and P ₂ . The frequency characteristics of the common mode reactor 10a are the same as in the second embodiment.
A DC reactor component 20b in FIG. 8B is an example in which a cable between both ends of the DC reactor 221 and the terminals P ₁ and P ₂ is passed through the magnetic core 10b constituting the common mode reactor. The number and type of magnetic cores are the same as in the second embodiment.

A DC reactor component 20 c in FIG. 8C is an example in which a capacitor 10 c is connected to both ends of the DC reactor 221. The number of capacitors is not limited to one, and a plurality of capacitors may be connected in series or in parallel. The type and characteristics of the capacitor are the same as in the third embodiment.
Further, a resistor 10d may be connected in parallel or in series with the capacitor 10c as in the DC reactor parts 20d and 20e shown in FIG. 8D and FIG. 8E. If comprised in this way, the unnecessary resonance resulting from the capacitor | condenser 10c and the peak of the noise which generate | occur | produces with it can be suppressed. Here, as with the capacitor 10c, a plurality of resistors 10d may be connected in parallel or in series.

Next, a fifth embodiment of the present invention will be described. In this embodiment, the main circuit portion 200 of the inverter and the DC reactor 221 are connected by a shielded cable 223 as noise reduction means.
Hereinafter, Example 7 according to the fifth embodiment will be described with reference to FIGS.

First, FIG. 9A shows a case where the main circuit unit 200 and the DC reactor 221 are housed in the casing 260 as in the prior art shown in FIG. The terminals P ₁ and P ₂ are connected by a shielded cable 223. In addition, 223a is a core wire of the cable 223, 223b is a shield part, and 261 is a wiring duct in which a part of the cable 223 is accommodated.

  Both ends of the shield portion 223b are connected to the metal housing of the DC reactor 221 and the metal housing of the main circuit portion 200, respectively. Although the connection method of the shield part 223b is not specifically limited, It is good to connect using the clamp components etc. so that the surface of the shield part 223b and a metal housing may surface-contact. If there is no metal housing, it may be connected to a portion where the impedance between the end portion of the shield portion 223b is the smallest among the portions that are connected to the ground line of the main circuit portion 200.

  Also, as shown in FIG. 9B, the main circuit part 200 side of the shield part 223b is connected to a metal casing, and the DC reactor 221 side of the shield part 223b is connected to the ground conductor plate 262 of the main circuit part 200. You may connect via H.224.

By connecting the main circuit unit 200 and the DC reactor 221 by the shielded cable 223 in this way, the common mode noise current flowing through the core wire 223a is shielded by the shield unit 223b, and thus the main circuit unit 200 and the DC reactor 221 are shielded. Radiation noise and conduction noise generated from the wiring between them can be reduced.
Furthermore, if a part of the cable 223 is accommodated in the wiring duct 261, it is more effective in reducing radiation noise.

  In addition, the power converter device which concerns on this invention is not limited to the embodiment or Example mentioned above at all, and can change variously in the range which does not deviate from the summary of this invention. For example, the semiconductor switching element constituting the power conversion device is not limited to the IGBT but may be an IEGT (electron injection promotion insulated gate transistor), a bipolar transistor, a MOSFET, or the like.

  The present invention is not limited to an inverter, but includes various types of power required to reduce common mode noise, such as a converter having an AC / DC converter and a DC reactor connected to a DC bus, an uninterruptible power supply (UPS), and the like. It can be applied to a conversion device.

10: Common mode noise reduction means 10a: Common mode reactor 10b: Magnetic core 10c: Capacitor 10d: Resistors 20a-20e: DC reactor component 100: Three-phase AC power supply 200, 200a-200e: Main circuit section 205a-205e: Semiconductor Module 210: AC / DC converter (first converter)
220: Smoothing capacitor 221: DC reactor 222: DC reactor cable 223: Shielded cable 223a: Core wire 223b: Shield part 224: Connection part 230: DC / AC conversion part (second conversion part)
240: Electronic device 241: Electronic device cable 250: Switch 260: Housing 261: Wiring duct 262: Ground conductor plate 270: Common mode noise reduction means 300: Motor 400: Input cable 401, 501: Earth wire 500: Output cable _{P 1, P 2, P 1} ', P 2': terminal

Claims (8)

A first converter that converts AC power into DC power by a semiconductor rectifier; and a second converter that converts DC power output from the first converter into AC power or DC power by a switching operation of the semiconductor switching element; In a power converter comprising: a DC reactor connected in series to a DC bus between the first converter and the second converter;
A power conversion device, wherein common mode noise reduction means is provided between both ends of the DC reactor and the DC bus. In the power converter device according to claim 1,
The DC bus has first and second terminals, and the first and second terminals are connected to both ends of the DC reactor via the common mode noise reducing means, respectively. . In the power converter device according to claim 1,
A power conversion device, wherein first and second terminals connected to the DC bus via the common mode noise reducing means are connected to both ends of the DC reactor, respectively. In the power converter device given in any 1 paragraph of Claims 1-3,
The common mode noise reduction means is a common mode reactor. In the power converter device given in any 1 paragraph of Claims 1-3,
The common mode noise reducing means includes at least a capacitor. In the power converter device according to claim 1 or 2,
The power converter according to claim 1, wherein the common mode noise reducing means is a shielded cable for connecting between both ends of the DC reactor and the DC bus. The power conversion device according to claim 6,
A part of the shielded cable is accommodated in a wiring duct. In the power converter device according to claim 6 or 7,
A power conversion device, wherein a shield portion of the shielded cable is connected to a ground conductor plate of the power conversion device.

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