JP6676888B2 - Power converter - Google Patents

Description

  The present invention relates to a power converter module, and more particularly to a power converter module that reduces a high-frequency noise signal generated by the module.

  Power modules are used as switching elements of power conversion devices used in various industries. This power module generates high-frequency voltage and current amplitude noise during the operation of the semiconductor device, and conducts and radiates the noise to peripheral devices to adversely affect the peripheral devices.

  In recent years, power semiconductor devices used in power modules have been increasingly shortened in switching time and voltage waveforms during switching by adopting new devices made of wide band gap materials such as SiC and GaN. The steepening is progressing. Accordingly, instantaneous voltage oscillation (surge voltage) at the time of switching, a reverse recovery current generated by a diode, and a generation level in a noise source are increasing. The noise leaks to the ground through a loop having a low impedance, particularly, a portion having a large ground capacitance, and affects other devices adjacent to the device via the ground line.

  As a technique for reducing a noise current leaking from an electric power converter such as an inverter to the ground, in order to increase the impedance of an insulating substrate of a power module to be used, Patent Document 1 uses an insulating substrate made of a material having a large dielectric loss. Propose that. In Patent Document 2, an insulating substrate of a power module has a two-layer structure, in which one layer is provided with a wiring layer or the like which contributes as an inductance in parallel to the insulating substrate, and an impedance at a specific frequency is provided by parallel resonance by LC. It is proposed to increase and reduce the leakage current to the ground.

  On the other hand, in Patent Document 3, by increasing the capacity (electrical coupling) between the output cable of the inverter and the ground pattern, the electrical coupling between the input cable and the output cable is reduced, and high-frequency noise superimposed on the output cable is input. It proposes a configuration that is difficult to transmit and guide to the cable and power supply side. In Patent Document 4, a capacitive element (impedance circuit) serving as a capacitor is formed on a heat sink in order to increase electrical coupling between a switching element of an inverter, which is a main noise source, and a heat sink at ground potential at a wide frequency. In addition, a configuration has been proposed in which a high-frequency noise current is positively released to the ground to make it difficult for the high-frequency current to flow to the power supply side.

JP 2008-35657 JP 2011-172329A JP 2012-1110092A JP 2012-196113 A

  In the technique proposed in Patent Document 2, the power module insulating substrate is not a conventional one-layer insulating layer but a multi-layer substrate, which leads to an increase in the power module manufacturing cost and a wiring pattern in the insulating layer. There is a problem that the manufacturing process is complicated, such as providing and arranging the chip inductor. Further, in order to obtain desired impedance characteristics, there are detailed restrictions on the length, thickness, position, and the like of the wiring pattern. Further, the frequency of noise generated by the gate control condition of the switching element such as the IGBT differs, and the frequency band in which the impedance is to be increased varies depending on the use condition of the switching element. That is, it is necessary to redesign the circuit design on the insulating substrate for each of the characteristics of the switching element and the use conditions such as the gate control and the operating temperature condition.

  Patent Documents 3 and 4 disclose electrical and magnetic components between parts in a system in order to minimize the use of noise components (ferrite cores, noise suppression sheets, LC filters) that lead to an increase in the size and cost of the system. By controlling the coupling, a noise propagation route is controlled. The following problems occur in each control method.

  In Patent Document 3, the capacity between the output cable and the ground is determined by the thickness of the insulating member between the U-phase, V-phase, and W-phase output wires and the ground potential pattern, the opposing surface area in the cable (the area of the closest and facing part). Surface area), etc., when a normal insulating material having a relative dielectric constant of about 3 or less is used, the coupling capacitance between the two is at most 100 pF or less, and as a propagation route for releasing a noise component of a frequency of 10 MHz or less. Does not have a sufficiently low impedance.

In Patent Literature 4, since the capacitance between each main circuit potential (P potential, N potential, U phase, V phase, W phase) before and after the switching element and the ground is different at each potential, between the routes leaking from each potential to the ground. Characteristic differs (resonance frequency at which the impedance decreases). That is, in order to reduce the impedance from the entire potential to the ground in a wide frequency band, it is necessary to provide a plurality of capacitance elements having optimal constants in consideration of variations in each potential and capacitance. In addition to controlling the noise propagation route, from the viewpoint of suppressing radiation noise at the time of switching, it is necessary to limit the loop in which the high-frequency current circulates to a region as narrow as possible.

  An object of the present invention is to provide a module for a power converter in which a high-frequency noise current is confined in the vicinity of a noise generation source to reduce noise conducted and radiated outside the module.

The present invention
A capacitor,
Is connected to one end of the capacitor, and the positive electrode potential end positive potential is applied DC voltage is connected to the other end of the capacitor, the negative electrode potential ends negative potential of the DC voltage is applied, and the positive electrode potential end A first switching element connected in series via a wiring between negative electrode potential terminals, a first diode connected in anti-parallel to the first switching element via a wiring, A second diode connected in anti-parallel to the second switching element via wiring , and a module having a circuit consisting of:
A power converter comprising:
The module comprises:
The positive electrode potential end is disposed on one surface of a first insulating substrate, and a first base made of metal is disposed on the other surface of the first insulating substrate;
An AC output terminal formed on one surface of the second insulating substrate and formed by a common connection point of the first and second switching elements and a common connection point of the first and second diodes; A second base made of metal is provided on the other surface of the second insulating substrate,
Disposing the negative potential end on one surface of a third insulating substrate, disposing a third base made of metal on the other surface of the third insulating substrate,
Inserting a first impedance adjusting member between the first base and the second base;
A second impedance adjusting member is interposed between the second base and the third base.

The first and second impedance adjusting members according to the present invention include:
Of the first and second switching elements connected in series, a junction capacitance between a collector and an emitter or a drain and a source of the switching element on the off-controlled side, the off-controlled switching element, and the switching element And a capacitance between the wiring and the third base or a capacitance between the wiring and the first base and the second impedance adjusting member or the first impedance adjusting. features of the member, such that the second base and the LC series resonant frequency of the loop, the noise current is propagated flowing through the capacitance between the AC output terminals is below 10 MHz, that each impedance is adjusted It is what it was.

The first impedance adjustment member according to the present invention is a member that functions as a first inductance of 0.1 to 10 μH , and the second impedance adjustment member is a second inductance of 0.1 to 10 μH. It is a member that functions as an inductance .

In the present invention , each of the members functioning as the first and second inductances is a chip inductor .

The member functioning as the first and second inductances according to the present invention is characterized in that each member has a spring shape in which an extremely fine wire is wound in a coil shape .

According to the present invention , the inductance value of the member functioning as the first and second inductances may be a capacitance of the capacitor, a wiring connecting a positive potential terminal and a negative potential terminal to the first and second switching elements, And the second series switching element, than the LC series resonance frequency of the loop in which the noise current flowing through the collector-emitter or drain-source junction capacitance of the off-controlled switching element propagates
Of the first and second switching elements connected in series, a junction capacitance between a collector and an emitter or a drain and a source of the switching element on the off-controlled side, the off-controlled switching element, and the switching element And a capacitance between the wiring and the third base or a capacitance between the wiring and the first base and the second impedance adjusting member or the first impedance adjusting. is obtained is characterized in that a member of, said second base and loops of the LC series resonance frequency of the noise current propagates flowing through the capacitance between the AC output terminals are respectively selected to be smaller .

The present invention is a power conversion device including a capacitor and a module,
The module comprises:
A positive potential terminal connected to one end of the capacitor, to which a positive potential of a DC voltage is applied; a negative potential terminal connected to the other end of the capacitor, to which a negative potential of a DC voltage is applied; A first switching element connected in series via a wiring between negative electrode potential terminals, a first diode connected in anti-parallel to the first switching element via a wiring, A second diode connected in anti-parallel to the second switching element via wiring.
A first base made of metal, a first insulating substrate laminated on the first base, a positive wiring layer laminated on the first insulating substrate and connected to the positive potential terminal, A first switching element and a first diode, each of which is individually stacked; a common connection point of the first and second switching elements, which are stacked on the first switching element and the first diode; An AC output section formed at a common connection point of the two diodes, a second switching element and a second diode individually stacked on the AC output section, and an AC output section stacked on the second switching element and the second diode. The negative electrode wiring layer connected to the negative electrode potential terminal, a second insulating substrate laminated on the negative electrode wiring layer, and a second base made of metal laminated on the second insulating substrate are electrically insulated. Enclosure Within, housed in a state of sandwiching the first and second base,
An AC output part having one end penetrated at a portion corresponding to an intermediate position between the first base and the second base in the insulating casing is connected to the first base and the second base in the casing. Stored in between,
In the first base, a portion where a capacitance is formed between the positive electrode wiring layer and the first base is separated from an adjacent portion where a capacitance is formed between the AC output portion and the first base, A first impedance-adjusting member is inserted into the separation point,
In the second base, a portion where a capacitance is formed between the negative electrode wiring layer and the second base is separated from an adjacent portion where a capacitance is formed between the AC output portion and the second base, It is characterized in that a second impedance adjusting member is interposed at the separation point.

According to the present invention , at least one of the members functioning as the first or second inductance has a size, a quantity, and a position facing the first and second insulating substrates. The area of at least one of the first and second bases is adjusted to change at least one of the capacity between the positive wiring layer and the first base and the capacity between the negative wiring layer and the second base. It is characterized by doing .

As described above, according to the present invention, the following effects can be obtained.
(1) Since a plurality of loops for separating and confining a high-frequency noise current generated by a voltage fluctuation of a switching element in a power conversion device from a low frequency to a high frequency in a module near a noise source for each frequency are formed. Electromagnetic compatibility) performance is improved, and noise and radiation noise transmitted to the outside of the module are reduced.
(2) During switching, a high-frequency current does not flow through a plurality of low-impedance loops at the same time, so that instantaneous increase in conduction noise and radiation noise at any timing during switching is reduced. This prevents a malfunction of the switching element during switching.
(3) Module reliability is improved. Since the base of the module is separated for each potential, the area ratio of the metal on the front side (circuit pattern side) and the back side (base side) of the ceramic substrate made by, for example, active metal brazing or copper direct bonding is close. Therefore, the stress applied to the interface between the ceramic substrate and the metal is reduced, and the reliability of the ceramic substrate with respect to thermal cycling is improved. Inductors and extra-fine springs placed between the ceramics serve to relieve the stress between the ceramic substrates.

FIG. 1 is a cross-sectional view of a module of an inverter according to an embodiment of the present invention. Sectional drawing of the module of the inverter which shows other embodiment of this invention. FIG. 4 is a noise propagation route diagram in the module equivalent circuit of the present invention. FIG. 4 is a diagram illustrating a resonance frequency-voltage characteristic of a noise propagation route according to the present invention. Sectional drawing of the module of the inverter which shows other embodiment of this invention. FIG. 2 is a plan view of an insulating substrate and a base arrangement. The basic block diagram of an inverter apparatus. The noise propagation route figure of an inverter device. Sectional drawing of the module of the conventional inverter. Sectional drawing of the conventional double-sided cooling card type module. The noise propagation route figure in the conventional module equivalent circuit. FIG. 7 is a diagram illustrating a resonance frequency-voltage characteristic of a conventional noise propagation route.

  The present invention relates to a metal part (base) that forms a main capacitance through an electrode pattern of a P (positive electrode) potential, an N (negative electrode) potential, and an AC (alternating current) potential of a module used in a power conversion device and an insulating substrate. Are separated for each of the opposing potentials, and between the base opposing the P potential and the base opposing the AC potential, and between the base opposing the N potential and the base opposing the AC potential, respectively. Is inserted with a member that contributes as an inductance. Prior to the description of the specific embodiments, the concept leading to the present invention will be described.

  FIG. 7 shows a configuration of a general inverter device as an example of a power conversion device. The converter 3 is connected to the commercial power supply 1 via the input wiring section 2 and converts an AC input voltage into a DC voltage. The converted DC voltage is applied to an inverter 5 through a direct current (DC) wiring section 4 having a smoothing capacitor and a snubber capacitor. The inverter 5 reversely converts the voltage into a predetermined AC voltage and outputs the converted AC voltage through an output wiring section 6 to an induction motor 7. Is applied to

  As the inverter 5, a module obtained by modularizing a switching element and a diode such as an IGBT or a MOSFET is used. The noise level is generated as the voltage change dv / dt during switching is larger, and the voltage jumps up during switching and the ringing of the voltage is larger. Increases. In other words, the higher the switching speed, the lower the switching loss and the higher the conversion efficiency, but there is a problem that the noise level increases.

FIG. 8 shows an equivalent circuit of the stray capacitance of each part of the inverter device shown in FIG. 7, in which a leakage current flows in a direction shown by an arrow, and a leakage current to the ground via a ground capacitance of each component is mainly. It becomes a noise propagation route. In order to satisfy the specification of the conducted noise, the absolute value of the noise generation amount of the noise source (only the W phase is shown in FIG. 8 as an example) is reduced, and at the same time, the noise is prevented from entering the input wiring section side and the commercial power supply side. It is important to control the impedance of the path through which the high-frequency current propagates. In particular, to prevent high-frequency noise signals from propagating to the commercial power supply and to prevent noise from being radiated into the space, intentionally create a conduction loop with low impedance as close to the noise source as possible, It is useful to confine this current to a narrow watershed.

FIG. 9 is a cross-sectional view of a 2in1 module of a general inverter, and FIG. 10 is a cross-sectional view of a double-sided cooling 2in1 module. In the module, a base 11 made of Cu or the like is arranged on one surface via an insulating substrate 10 made of Al ₂ O ₃ or the like, a wiring layer 12 made of Cu or the like is arranged on the other surface, and a switching element (IGBT or MOSFET) 13 and a diode 14 are provided. Reference numeral 15 denotes a wiring made of, for example, Al.

FIG. 11 shows an equivalent circuit of these 2in1 modules, and shows a propagation route at the time of turning off the lower arm switching element of the inverter as a noise source as an example. In any case, capacitors C _PG , C _NG , and C _AC-G are formed between the P potential, the N potential, and the AC potential and the base 11 that is often dropped to the ground potential via the insulating substrate 10 of the module.

  When an IGBT is used as the switching element, the junction capacitance Cce between the collector and the emitter (drain-source junction capacitance Cds in the case of a MOSFET) and the capacitance Cfilm of the snubber capacitor (film capacitor) of the DC wiring section 4 are used. Assuming that a parasitic inductance of a circulating loop including a snubber capacitor (hereinafter, this circulating loop is referred to as a noise propagation route 1) is L and a parasitic resistance is R, LC series resonance occurs at a frequency f represented by the equation (1). At that frequency, the impedance drops to the parasitic resistance R. For this reason, in the loop indicated by the noise propagation route 1, a high-frequency oscillation current around the resonance frequency f flows preferentially in the noise spectrum generated by the noise source.

As a loop of a high-frequency noise current different from the noise propagation route 1, a junction capacitance Cce between the collector and the emitter, an N potential, a capacitance C _NG between the N potential and the base, a capacitance C _AC-G between the AC potential and the base, AC A noise propagation route 2 circulating through the base via the potential, a capacitance C _{AK of} a diode arranged in anti-parallel with the switching element, an AC potential, a junction capacitance Cce between the collector and the emitter, and a noise propagation route 3 circulating through the wiring 15. Exists.

  The noise current flowing through each loop is around the frequency at which the impedance is reduced by the LC series resonance, and the resonance frequency is the collector of the IGBT during switching (the IGBT of the lower arm in FIG. 11) as shown in FIG. It depends on the emitter voltage Vce. This is because the junction capacitance of the IGBT or the diode during switching changes as the collector-emitter voltage Vce or the anode-cathode voltage of the diode increases as the junction capacitance Cce decreases.

  The problem here is that the dependence on the voltage Vce is very close to the resonance frequency of the noise propagation routes 2 and 3 at a certain voltage Vce as shown in FIG. In this case, a noise signal flows through both routes, and transmission noise and radiation noise increase.

Further, in the noise propagation routes 1 to 3, even in the case of the route 1 having the lowest resonance frequency, the frequency is usually 10 MHz or more, and does not form a loop for circulating a component of 10 MHz or less which is a main component of the conducted noise. The low-frequency noise signal of 10 MHz or less has a large area (space) outside the loop shown in FIG. 11, that is, the output wiring unit 6, the DC wiring unit 4, the converter 3, and the input wiring unit 2 shown in FIG. It will propagate the low impedance route. This is not preferable because various noise filters need to be installed in order to increase the EMC of the inverter device, and various shield measures for suppressing radiation noise are additionally required.
Therefore, in the present invention, the noise signal is confined by appropriately adjusting and setting the impedance (resonance frequency) of the loop near the noise source such as the noise propagation routes 1 to 3.

FIG. 1 is a cross-sectional view of a 2-in-1 module of an inverter having an IGBT as a switching element and having an upper-arm IGBT-u1 and a lower-arm IGBT-u2 connected in series in a U-phase. . In each IGBT, a base 11 is arranged on one surface with an insulating substrate 10 interposed therebetween as in FIG. 9, and switching elements 13-u1, 13-u2 and a diode 14-u1 are arranged on the other surface via a wiring layer 12. 14-u2 is arranged. 9 is different from FIG. 9 in that the base 11 in the module is separated from an AC part in which IGBT-u1 and IGBT-u2 are connected in series and outputs an alternating current, and a part of IGBT-u2 and N potential.

  That is, the base 11 is separated in terms of potential from the opposing P potential, N potential, and AC potential, and the inductors 21 and 22 as members for impedance adjustment are interposed at the separated positions. As the inserted inductors 21 and 22, a member that functions as an inductance having a capacity of about 100 nH to 10 μH is used. This inductor is, for example, a surface mount type chip coil, and is connected between the bases of IGBT-u1 and IGBT-u2 and between the base of IGBT-u2 and N potential by soldering or the like. As the inductors 21 and 22, as shown in FIG. 2, an ultrafine spring in which a SUS piano wire is wound in a coil shape may be arranged. In other words, if the inductance value acts within a range of 100 nH to 10 μH. Good.

  FIG. 3 shows a noise propagation route when the IGBT-u2 becomes a noise source when the IGBT-u2 is turned off in an equivalent circuit when the inductors 21 and 22 are connected. FIG. 4 shows the resonance frequency for each noise propagation route. By arranging the inductors 21 and 22 that operate as inductances, the resonance frequency of the noise propagation route 2 is shifted to a lower frequency side.

For example, when the module is configured by an IGBT and a chip inductance rated at 10 μH is provided as the inductors 21 and 22, the circulating inductance of the noise propagation route 2 is 10 μH, the capacitance C _PG = 200 pF, C _AC-G = 200 pF, and the IGBT- If Cce of u2 (when Vce = 0 V) = 20 nF and Cce of IGBT-u1 (when Vce = 600 V) = 1 nF, the resonance frequency of the noise propagation route 2 depends on the junction capacitance Cce between the drain and source of the IGBT. Nevertheless, it becomes 5 MHz.

  On the other hand, when the loop inductance of the route 1 is 30 nH, the resonance frequency of the route 1 is 6.5 MHz at Vce = 0 V between the emitter and the collector, and 30 MHz at Vce = 600 V. That is, as shown in FIG. 4, the resonance frequency of the noise propagation route 2 is lower than the resonance frequency of the noise propagation route 1 irrespective of the junction capacitance Cce between the emitter and the collector of the IGBT.

  As a result, conduction noise and radiation noise do not increase due to approaching or coincidence of resonance frequencies in a plurality of noise propagation routes as shown in FIG. 12, and a main component of conduction noise having a frequency of 10 MHz or less is reduced to a noise source (switching). It can be confined to the circulation route (noise propagation route 2) near the element 13) with high intensity.

  Note that the larger the inductors 21 and 22 are used, the larger the resistance R of the inductor becomes, the larger the impedance at the time of resonance becomes, and the more likely the noise current passes through an external low impedance route. That is, it is desirable to use components having the smallest possible inductance value of the inductors 21 and 22. 1, the voltage oscillation of the base 11 becomes larger than that of the related art shown in FIG. 8, but it is considered by the system whether it is better to drop the base 11 to the ground of the inverter device. , It is dropped through a low impedance.

  In FIG. 3, the case where the switching element of the lower arm is turned off has been described, but also in the case of the upper arm, the resonance frequency of the loop via the base potential is determined by the inductance formed between the P potential and the AC potential, similarly to the lower arm. Is reduced to 10 MHz or less, so that a noise confinement route at the time of switching is formed.

  FIG. 5 shows an embodiment in which the present invention is applied to a double-sided cooling card type 2 in 1 module. In the double-sided cooling card type 2 in 1 module, a housing is formed in a state where the left and right portions of the base 11 are sandwiched by a case 16 made of resin, and components such as a switching element and a diode are arranged inside the housing. That is, the switching element 13-u1 and the diode 14-u1 are arranged between the wiring layer 12P having the P potential and the AC output section (AC terminal) 17, and the switching element 13 is arranged between the wiring layer 12N having the N potential and the AC terminal 17. -u2 and a diode 14-u2. Further, the insulating substrate 10 and the base 11 which are stacked are disposed on the wiring layers 12P, 12N and the case 16, respectively.

In the module configured as described above, the base 11 is separated from the insulating substrate 10 at each of the left and right sides in the drawing, and the inductors 21 and 22 are respectively disposed at the separated portions. Accordingly, in the potential portion formed on the base 11 as in the first embodiment, the AC potential (AC terminal 17) and the base potential forming the main capacitance C _AC-G , the P potential and the main capacitance C _PG are formed. Between the N potential and the base potential forming the main capacitance C _NG and between the AC potential and the base potential forming the main capacitance C _AC-G , respectively. It has a configuration in which a member that functions as an inductance of .1 to 10 μH is arranged.

FIG. 6 is a plan view of another example of the arrangement of the base 11 and the inductor that are arranged to face the insulating substrate 10. That is, the inductor has 21a (22a) arranged at the left and right positions in the drawing and 21b (22b) arranged at the upper and lower positions in the drawing. This is based on the fact that the capacities C _PG and C _NG are determined by the size of the area of the base 11 in contact with the insulating substrate 10 (or the case 16). For example, the capacity C _PG is determined by equation (2).
C _PG = dielectric constant of insulating substrate (ε) × S (area in contact with insulating substrate) / thickness of insulating substrate (d) (2)
Therefore, as shown in FIG. 6, the number of bases 11 to be cut by a spring or the like (four places in FIG. 6) is increased, or the base 11 to be opposed to (contacted with) the insulating substrate 10 is increased by cutting with a long spring or the like. Decrease. As a result, the capacitance C _PG decreases according to the equation (2). Figure 6 (a) (b) in its area S1, S2 in the example was that of FIG. 6 (a)> FIG. 6 (b), when as an example the N potential and base capacitance C _NG in this magnitude relationship, S1> In S2, C _N-G1 > C _N-G2 . As described above, the capacitances C _PG and C _NG can be changed depending on the size and quantity of the inductor and the position facing the insulating substrate 10.

Therefore, also in the second embodiment, as in the first embodiment, the resonance frequency of the loop passing from the noise source to the base potential can be shifted to the low frequency side, and the component of 10 MHz or less, which is the main component of the conduction noise, is reduced. A loop for circulation is formed, and the capacities C _PG and C _NG can be arbitrarily varied in the double-sided cooling card type 2 in 1 module. This makes it possible to reduce conduction noise and radiation noise leaking to the outside of the inverter module, that is, to the output wiring section 6, the DC wiring section 4, the input wiring section 2, and the like.

3 Converter 4 Inverter 10 Insulating substrate 11 Metal part (base)
DESCRIPTION OF SYMBOLS 12 ... Wiring layer 13 ... Switching element 14 ... Diode 15 ... Wiring 16 ... Case 17 ... AC output part 18 ... Bus bar 21, 22 ... Member (inductor)

Claims (12)

A capacitor,
Is connected to one end of the capacitor, and the positive electrode potential end positive potential is applied DC voltage is connected to the other end of the capacitor, the negative electrode potential ends negative potential of the DC voltage is applied, and the positive electrode potential end A first switching element connected in series via a wiring between negative electrode potential terminals, a first diode connected in anti-parallel to the first switching element via a wiring, A second diode connected in anti-parallel to the second switching element via wiring , and a module having a circuit consisting of:
A power converter comprising:
The module comprises:
The positive electrode potential end is disposed on one surface of a first insulating substrate, and a first base made of metal is disposed on the other surface of the first insulating substrate;
An AC output terminal formed on one surface of the second insulating substrate and formed by a common connection point of the first and second switching elements and a common connection point of the first and second diodes; A second base made of metal is provided on the other surface of the second insulating substrate,
Disposing the negative potential end on one surface of a third insulating substrate, disposing a third base made of metal on the other surface of the third insulating substrate,
Inserting a first impedance adjusting member between the first base and the second base;
A power converter , wherein a second impedance adjusting member is interposed between the second base and the third base. The first and second members for impedance adjustment include:
Of the first and second switching elements connected in series, a junction capacitance between a collector and an emitter or a drain and a source of the switching element on the off-controlled side, the off-controlled switching element, and the switching element And a capacitance between the wiring and the third base or a capacitance between the wiring and the first base and the second impedance adjusting member or the first impedance adjusting. And the impedance is adjusted such that the LC series resonance frequency of the loop through which the noise current flowing through the member and the capacitor between the second base and the AC output terminal propagates is 10 MHz or less. The power conversion device according to claim 1. The first impedance-adjusting member is a member that functions as a first inductance of 0.1 to 10 μH, and the second impedance-adjusting member is a second inductance of 0.1 to 10 μH. The power converter according to claim 1, wherein the power converter is a functioning member. The power converter according to claim 3, wherein the members functioning as the first and second inductances are each a chip inductor. The power converter according to claim 3, wherein each of the members functioning as the first and second inductances has a spring shape in which a very fine wire is wound in a coil shape. The inductance values of the members functioning as the first and second inductances are the capacitance of the capacitor, the wiring connecting the positive and negative potential ends and the first and second switching elements, the first and second switching elements, Of the switching elements, the LC series resonance frequency of a loop in which a noise current flowing through the collector-emitter or the drain-source junction capacitance of the switching element that is controlled to be off propagates,
Of the first and second switching elements connected in series, a junction capacitance between a collector and an emitter or a drain and a source of the switching element on the off-controlled side, the off-controlled switching element, and the switching element And a capacitance between the wiring and the third base or a capacitance between the wiring and the first base and the second impedance adjusting member or the first impedance adjusting. 4. The LC series resonance frequency of a loop through which a noise current flowing through the member and the capacitor between the second base and the AC output terminal propagates is selected to be small. The power converter according to any one of claims 1 to 5. A power converter including a capacitor and a module,
The module comprises:
A positive potential terminal connected to one end of the capacitor, to which a positive potential of a DC voltage is applied; a negative potential terminal connected to the other end of the capacitor, to which a negative potential of a DC voltage is applied; A first switching element connected in series via a wiring between negative electrode potential terminals, a first diode connected in anti-parallel to the first switching element via a wiring, A second diode connected in anti-parallel to the second switching element via wiring.
A first base made of metal, a first insulating substrate laminated on the first base, a positive wiring layer laminated on the first insulating substrate and connected to the positive potential terminal, A first switching element and a first diode, each of which is individually stacked; a common connection point of the first and second switching elements, which are stacked on the first switching element and the first diode; An AC output section formed at a common connection point of the two diodes, a second switching element and a second diode individually stacked on the AC output section, and an AC output section stacked on the second switching element and the second diode. The negative electrode wiring layer connected to the negative electrode potential terminal, a second insulating substrate laminated on the negative electrode wiring layer, and a second base made of metal laminated on the second insulating substrate are electrically insulated. Enclosure Within, housed in a state of sandwiching the first and second base,
An AC output part having one end penetrated at a portion corresponding to an intermediate position between the first base and the second base in the insulating casing is connected to the first base and the second base in the casing. Stored in between,
In the first base, a portion where a capacitance is formed between the positive electrode wiring layer and the first base is separated from an adjacent portion where a capacitance is formed between the AC output portion and the first base, A first impedance-adjusting member is inserted into the separation point,
In the second base, a portion where a capacitance is formed between the negative electrode wiring layer and the second base is separated from an adjacent portion where a capacitance is formed between the AC output portion and the second base, A power converter, wherein a second member for adjusting impedance is interposed at the separation point. The first impedance-adjusting member is a member that functions as a first inductance of 0.1 to 10 μH, and the second impedance-adjusting member is a second inductance of 0.1 to 10 μH. The power converter according to claim 7, which is a functioning member. The power converter according to claim 8, wherein the members functioning as the first and second inductances are each a chip inductor. The power converter according to claim 8, wherein each of the members functioning as the first and second inductances has a spring shape in which a very thin wire is wound in a coil shape. Noise flowing through the capacitor, the positive wiring layer and the negative wiring layer, and a junction capacitance between a collector and an emitter or a drain and a source of a switching element of the first and second switching elements that is controlled to be off. Than the LC series resonance frequency of the loop through which the current propagates,
A collector-emitter or drain-source junction capacitance of the off-controlled switching element; and a positive wiring layer or a negative electrode on which the off-controlled switching element and a diode connected in anti-parallel to the switching element are stacked. A wiring layer, a capacitance between the positive wiring layer and the first base or a capacitance between the negative wiring layer and the second base, and the first impedance adjusting member or the second impedance adjusting member; , Are selected so that the LC series resonance frequency of the loop through which the noise current flowing through the first or second impedance adjusting member and the capacitance between the AC output unit propagates is reduced. The power converter according to any one of claims 7 to 10. The first or second member depends on at least one of the members functioning as the first and second inductances, depending on the size, the number, and the position facing the first and second insulating substrates. Adjusting the area of at least one of the bases to change at least one of the capacity between the positive wiring layer and the first base and the capacity between the negative wiring layer and the second base. The power converter according to any one of claims 8 to 11.

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