TW201530992A - Power-converting device having common mode noise-suppressing function - Google Patents

Abstract

The disclosure relates to a power-converting device having a common mode noise-suppressing function. The power-converting device includes a ground terminal, a power-converting unit, a DC bus capacitor unit, a filter capacitor unit, a filter inductor unit and a compensation circuit. The filter inductor unit is constituted by three primary winding inductors and three secondary winding inductors in the present invention, so that the power-converting unit may be constituted the compensation circuit through utilizing the three secondary winding inductors with, for example, a compensation unit of a compensation capacitor. One skilled in the technique field can select an appropriate turn ratio of the primary winding inductor to the secondary winding inductor, and the common mode noise occurred at the harmonic frequency of the power converter can be easily and effectively suppressed.

Description

Power conversion device with function of suppressing common mode noise 【0001】

The present application relates to a three-phase power converter, and more particularly to a power conversion device having a function of suppressing common mode noise connected to a three-phase three-wire low frequency AC power source or load.

【0002】

In three-phase AC-DC, DC-AC, UPS, wind and solar systems, a three-phase power converter is usually required. Figure 1 shows the topology of a basic three-phase power converter. The three-phase power converter 1' mainly includes: a power conversion unit 11', a filter inductor group 12', a filter capacitor group 13', and a The power supply impedance stabilizing network 14'; wherein the three bridge arm midpoints (A', B', and C') of the power conversion unit 11' as the AC terminals are respectively coupled to the three filter inductors of the filter inductor group 12' ( L _F1 ', L _F2 ', and L _F3 '); and, the three filter inductors (L _F1 ', L _F2 ', and L _F3 ') are respectively coupled to the three filter capacitors Cx of the filter capacitor group 13' Wherein the three filter capacitors Cx' are star-connected, and one end of the three filter capacitors Cx' is coupled to three phase terminals (Ua', Ub', and Uc') of the external power grid 2', The other ends are connected to each other to form a neutral point N'. Further, a Line Impedance Stabilization Network (LISN) 14' can be coupled between the power grid 2' and the filter capacitor group 13' for use as the three-phase power converter 1'. Auxiliary equipment for conducting electromagnetic interference tests. In addition, as shown in FIG. 1, the output end of the power conversion unit 11' is formed by DC filter capacitors C _B0 ', C _B1 ' and C _B2 ' respectively forming three DC terminals O', P' and Q', wherein the DC terminals O' is the DC bus midpoint O', which is the common terminal of the DC filter capacitors C _B1 ' and C _B2 '.

[0003]

In the three-phase power converter 1', it is assumed that C ₀ ' is the total distributed capacitance between the DC bus connected to the DC filter capacitors C _B0 ', C _B1 ' and C _B2 ' and the ground GND ' C _1A ', C _1B ', and C _1C ' are the distributed capacitances of the midpoints (A', B', and C') of each of the power conversion units 11' to the ground GND', respectively. Thus, when the power conversion unit 11' performs a potential jump, the distributed capacitances _C1A ', _C1B ', and _C1C ' generate a displacement current, and the displacement current further flows into the ground GND', thereby forming common mode noise. (common mode current). Reference is continued to the solution for suppressing common mode noise of the three-phase power converter shown in FIG. The topology of the three-phase power converter shown in FIG. 2 is coupled by a passive common mode filter 15' to the filter capacitor group 13' of the grid 2' and the three-phase power converter 1' shown in FIG. Therein, the passive common mode filter 15' includes a common mode inductor 151' and a filter capacitor group 152' formed by three filter capacitors C _Y ' that are star-connected to each other.

[0004]

Although the solution shown in FIG. 2 can indeed solve the common mode noise generated in the three-phase power converter 1' of FIG. 1, the common mode is caused by the large volume and high cost of the common mode inductor L _CM ' The design and integration of the inductor 151' is difficult. As shown in the voltage spectrum diagram of FIG. 3, curve 1 is a voltage spectrum diagram of the three-phase power converter 1' shown in FIG. 1, and curve 2 is a voltage spectrum diagram of the three-phase power converter shown in FIG. . From the voltage spectrum diagram of Fig. 3, it can be found that the resonance of the power converter is even between the grid 2' to which the passive common mode filter 15' is coupled and the filter capacitor group 13' of the three-phase power converter 1'. At the frequency f ₀ , there is still a large noise, indicating that the passive common mode filter 15' has a poor noise suppression effect on the three-phase power converter 1'.

[0005]

Combining the above understanding of the common mode noise solutions of various three-phase power converters, we can know that the current common mode noise solutions have some shortcomings and shortcomings; in view of this, the inventors of this case tried to study them. The invention was finally developed to complete the present invention.

[0006]

In order to overcome the defects in the prior art, the main object of the present invention is to provide a power conversion device having a function of suppressing common mode noise, which mainly comprises three sets of main winding inductances and three sets of auxiliary winding inductances to form a filter inductor unit, so that the power is made. The main power conversion unit inside the conversion device can be coupled to the three phase terminals of the external electrical device through the three sets of main winding inductances; at the same time, the three sets of auxiliary winding inductances are combined with a compensation unit such as a compensation capacitor to constitute A set of compensation lines allows the engineer to easily and effectively suppress the common mode noise at the resonant frequency of the power converter by selecting the appropriate turns ratio of the main winding inductance and the auxiliary winding inductance.

【0007】

Accordingly, in order to achieve the object of the present invention, the inventors of the present application have proposed a power conversion apparatus having a function of suppressing common mode noise, which includes:

[0008]

a ground terminal;

【0009】

a power conversion unit having a first DC terminal, a second DC terminal, a first AC terminal, a second AC terminal, and a third AC terminal; wherein the first DC terminal and the second The DC terminal is a first electrical device coupled to the outside;

[0010]

a DC bus capacitor unit coupled between the first DC terminal and the second DC terminal;

[0011]

a filter capacitor unit includes a first filter capacitor, a second filter capacitor, and a third filter capacitor, wherein each of the first filter capacitor, the second filter capacitor, and the third filter capacitor are respectively coupled a first phase terminal, a second phase terminal and a third phase terminal of a second electrical device to the outside, the other ends of the first filter capacitor, the second filter capacitor and the third filter capacitor are each other Connected into a common end;

[0012]

A filter inductor unit includes: a first main winding inductor having a first main winding low frequency end and a first main winding high frequency end, wherein the first main winding low frequency end is coupled to the first phase terminal And the third filter capacitor, the first main winding high frequency end is coupled to the first AC terminal; a first auxiliary winding inductor is inductively coupled to the first main winding and has a first auxiliary winding low frequency end And a first auxiliary winding high frequency end, wherein the low frequency end of the first auxiliary winding is coupled to the common end; a second main winding inductance having a second main winding low frequency end and a second main winding high frequency The second main winding low frequency end is coupled to the second phase terminal and the second filter capacitor, the second main winding high frequency end is coupled to the second AC terminal; a second auxiliary winding The inductor is inductively coupled to the second main winding, and has a second auxiliary winding low frequency end and a second auxiliary winding high frequency end, wherein the second auxiliary winding low frequency end is coupled to the first auxiliary winding high frequency end a third main winding inductance with a first a low frequency end of the main winding and a high frequency end of the third main winding, wherein the low frequency end of the second main winding is coupled to the first filter capacitor of the third phase terminal, and the high frequency end of the third main winding is coupled to the a third AC terminal; and a third auxiliary winding inductor inductively coupled to the third main winding and having a third auxiliary winding low frequency end and a third auxiliary winding high frequency end, wherein the third auxiliary winding low frequency end The high frequency end of the second auxiliary winding is coupled to the ground end of the third auxiliary winding.

[0013]

A specific embodiment of the power conversion device having the function of suppressing the common mode noise according to the present invention further includes a compensation unit, one end of the compensation unit is coupled to the high frequency end of the third auxiliary winding, and the other end is coupled to the Ground terminal.

[0014]

According to a specific embodiment of the power conversion device having the function of suppressing common mode noise according to the present invention, the compensation unit is selected from any one of the following groups: a compensation capacitor, a compensation inductor, a compensation resistor, and a series connection of the above two. Combination, combination of the above three.

[0015]

According to an embodiment of the power conversion device having the function of suppressing common mode noise according to the present invention, the compensation unit is composed of a compensation inductor and a compensation capacitor in series, and the inductance Lcomp of the compensation inductance conforms to the following calculation formula: Lcomp< 2(M-3L'); wherein M is the mutual inductance of the three main winding inductances and the three auxiliary winding inductances inside the filter inductor unit, and L' is the inductance of the three auxiliary winding inductors inside the filter inductor unit the amount.

[0016]

According to a specific embodiment of the power conversion apparatus having the function of suppressing common mode noise according to the present invention, the inductance Lcomp of the compensation inductance is in accordance with the following calculation formula: Lcomp = M - 3L'.

[0017]

A specific embodiment of a power conversion device having a function of suppressing common mode noise according to the present invention, a turns ratio of the first main winding inductance to the first auxiliary winding inductance, the second main winding inductance and the second auxiliary winding The turns ratio of the inductor and the turns ratio of the third main winding inductance to the third auxiliary winding inductance are between 3:1.3 and 3:0.7. And, preferably, the turns ratio of the first main winding inductance to the first auxiliary winding inductance, the turns ratio of the second main winding inductance to the second auxiliary winding inductance, and the third main winding inductance The third auxiliary winding inductance has a turns ratio of 3:1.

[0018]

According to a specific embodiment of the power conversion apparatus having the function of suppressing common mode noise according to the present invention, the power conversion unit is a two-level power converter, a three-level power converter or other multi-level power converter.

[0019]

According to a specific embodiment of the power conversion device having the function of suppressing the common mode noise, the first DC terminal and the second DC terminal are coupled to a first electrical device, wherein the first electrical device is Capacitor, AC to DC rectification unit, DC to AC rectification unit, and battery.

[0020]

According to a specific embodiment of the power conversion device having the function of suppressing common mode noise according to the present invention, the power conversion device having the function of suppressing common mode noise further includes a second power conversion unit coupled to the first electrical The device is between the first DC terminal and the second DC terminal.

[0021]

According to a specific embodiment of the power conversion apparatus having the function of suppressing common mode noise according to the present invention, the second power conversion unit is an alternating current to direct current rectifying unit or flows to the alternating current inverting unit.

[0022]

According to a specific embodiment of the power conversion device having the function of suppressing common mode noise, the first phase terminal, the second phase terminal and the third phase terminal are coupled to a second electrical device, wherein The second electrical device is a grid or a motor.

[0023]

According to a specific embodiment of the power conversion apparatus having the function of suppressing common mode noise according to the present invention, the power conversion apparatus having the function of suppressing common mode noise further includes an electromagnetic interference filter, and the electromagnetic interference filter coupling Connected between the filter capacitor unit and the first phase terminal, the second phase terminal and the third phase terminal.

[0024]

According to a specific embodiment of the power conversion device having the function of suppressing common mode noise, the electromagnetic interference filter is a set of differential mode filters, comprising: a first electromagnetic interference filter inductor, one end of which is coupled Connected to the first phase terminal, and the other end of the terminal is coupled to the first filter capacitor; a second electromagnetic interference filter inductor, one end of which is coupled to the second phase terminal, and the other end of which is coupled to The second electromagnetic interference filter inductor has one end coupled to the third phase terminal and the other end coupled to the third filter capacitor; a first electromagnetic interference filter capacitor having one end Is coupled to the first electromagnetic interference filter inductor, and the other end of the filter is coupled to the second electromagnetic interference filter inductor; a second electromagnetic interference filter capacitor, one end of which is coupled to the second electromagnetic interference filter inductor, And the other end is coupled to the third electromagnetic interference filter inductor; and a third electromagnetic interference filter capacitor, one end of which is coupled to the first electromagnetic interference filter inductor, and the other end of which is coupled to the third Electricity Interference filter inductor.

[0025]

According to a specific embodiment of the power conversion device having the function of suppressing common mode noise, the electromagnetic interference filter is a set of common mode filters, and includes: a first electromagnetic interference filter inductor, one end of which is coupled Connected to the first phase terminal, and the other end of the terminal is coupled to the first filter capacitor; a second electromagnetic interference filter inductor, one end of which is coupled to the second phase terminal, and the other end of which is coupled to The second electromagnetic interference filter inductor has one end coupled to the third phase terminal and the other end coupled to the third filter capacitor; a first electromagnetic interference filter capacitor having one end Is coupled to the third electromagnetic interference filter inductor, and the other end of the filter is coupled to the ground; a second electromagnetic interference filter capacitor, one end of which is coupled to the second electromagnetic interference filter inductor, and the other end thereof The third electromagnetic interference filter capacitor is coupled to the first electromagnetic interference filter inductor, and the other end of the filter is coupled to the ground.

[0026]

According to a specific embodiment of the power conversion apparatus having the function of suppressing common mode noise according to the present invention, the power conversion apparatus is a three-phase three-wire power conversion apparatus.

[0027]

Compared to the prior art, the technology of the present invention has the following advantages:

[0028]

1. The power conversion device with the function of suppressing common mode noise proposed by the present invention, the main technical feature of which is the topology design of the filter inductor unit and the compensation circuit; wherein, the three sets of main winding inductance and three sets of auxiliary winding inductances are formed. The filter inductor unit is configured such that the power conversion unit can be coupled to the three phase terminals of the external electrical device through the three sets of main winding inductances; and at the same time, the three sets of auxiliary winding inductors are used to cooperate with a compensation unit such as a compensation capacitor to form The compensation circuit enables the engineer to significantly and effectively suppress the common mode noise at the resonant frequency of the power converter by selecting the appropriate turns ratio of the main winding inductance and the auxiliary winding inductance.

[0029]

2. According to the above first point, and because the three sets of auxiliary winding inductances are mainly used to guide the common mode current (common mode noise) to the ground, the three sets of auxiliary winding inductances can be wound out with relatively thin wires. In this way, the volume and manufacturing cost of the common mode filter can also be effectively saved.

[0051]

1'‧‧‧Three-phase power converter

11’‧‧‧Power Conversion Unit

12'‧‧‧Filter Inductor Group

13'‧‧‧Filter Capacitor Set

14'‧‧‧Power impedance stable network

A’‧‧‧ midpoint of the bridge arm

B’‧‧‧ midpoint of the bridge arm

C’‧‧‧ midpoint of the bridge arm

L _F1 '‧‧‧Filter Inductor

L _F2 '‧‧‧Filter Inductor

L _F3 '‧‧‧Filter Inductor

Cx’‧‧‧Filter Capacitor

2’‧‧‧Power grid

Ua’‧‧‧first phase terminal

Uc’‧‧‧ third phase terminal

N’‧‧‧Neutral point

Ub’‧‧‧Second phase terminal

C _B0 '‧‧‧DC filter capacitor

C _B1 '‧‧‧DC filter capacitor

C _B2 '‧‧‧DC filter capacitor

O’‧‧‧ DC end

P’‧‧‧ DC terminal

Q’‧‧‧ DC end

C _1A '‧‧‧Distributed capacitance

GND'‧‧‧ Ground

C _1B '‧‧‧Distributed capacitance

C _1C '‧‧‧Distributed capacitance

15'‧‧‧Passive Common Mode Filter

L _CM '‧‧‧ Common mode inductance

151'‧‧‧Common mode inductance

152'‧‧‧Filter Capacitor Set

C _Y '‧‧‧Filter Capacitor

C ₀ '‧‧‧Distributed capacitance

1‧‧‧Power conversion device with suppression of common mode noise

11‧‧‧Power conversion unit

12‧‧‧Filter capacitor unit

14‧‧‧Compensation line

13‧‧‧Filter Inductance Unit

P‧‧‧First DC terminal

Q‧‧‧second DC terminal

A‧‧‧First AC terminal

B‧‧‧Second AC terminal

C‧‧‧third AC terminal

CB0‧‧‧DC bus capacitor unit

CB1‧‧‧first bus capacitor

CB2‧‧‧Second bus capacitor

O‧‧‧ DC bus midpoint

Cx1‧‧‧first filter capacitor

Cx2‧‧‧second filter capacitor

CX3‧‧‧ third filter capacitor

2‧‧‧Electrical installation

Ua‧‧ first phase terminal

Ub‧‧‧Second phase terminal

Uc‧‧‧ third phase terminal

N‧‧‧ public end

15‧‧‧Power impedance stable network

LA‧‧‧First main winding inductance

LA’‧‧‧First auxiliary winding inductance

LB‧‧‧Second main winding inductance

LB’‧‧‧Second auxiliary winding inductance

LC‧‧‧ Third main winding inductance

LC'‧‧‧ Third auxiliary winding inductance

A‧‧‧First AC terminal

141‧‧‧Compensation unit

GND‧‧‧ ground terminal

Ccomp‧‧‧compensation capacitor

Lcomp‧‧‧Compensated inductance

Z _LISN ‧‧‧Equivalent impedance of the power supply impedance stabilization network

M‧‧‧ mutual inductance

L‧‧‧Inductance

L’‧‧‧ total inductance

u _AO ‧‧‧ voltage

u _BO ‧‧‧ voltage

u _CO ‧‧‧ voltage

Ucomp‧‧‧compensation voltage

Ccm‧‧‧ equivalent common mode capacitor

C1a‧‧‧distributed capacitor

C1b‧‧‧distributed capacitor

C1c‧‧‧Distributed capacitance

Co‧‧‧distributed capacitor

17‧‧‧Electromagnetic interference filter

LDM1‧‧‧First Differential Mode Filter Inductor

LDM2‧‧‧Second differential mode filter inductor

LDM3‧‧‧ third differential mode filter inductor

Cxx1‧‧‧First Differential Mode Filter Capacitor

Cxx2‧‧‧Second differential mode filter capacitor

Cxx3‧‧‧ third differential mode filter capacitor

LCM1‧‧‧First Common Mode Filter Inductor

LCM2‧‧‧Second common mode filter inductor

LCM3‧‧‧ Third Common Mode Filter Inductor

CY1‧‧‧First Common Mode Filter Capacitor

CY2‧‧‧Second common mode filter capacitor

CY3‧‧‧ third common mode filter capacitor

11a‧‧‧second power conversion unit

2a‧‧‧ grid

2b‧‧‧Motor

2c‧‧‧Nonlinear load

2d‧‧‧Battery

[0030]

Figure 1 is a topological diagram of a basic three-phase power converter.

Figure 2 is a diagram of a solution for suppressing common mode noise of a basic three-phase power converter.

Figure 3 is a voltage spectrum diagram.

4 is a first topological structural view of a power conversion apparatus having a function of suppressing common mode noise according to the present invention.

Fig. 5 is a second topological structural view of a power conversion device having a function of suppressing common mode noise according to the present invention.

6 is a topology diagram of a power conversion unit.

FIG. 7 is a diagram of an equivalent common mode noise model of the topology shown in FIG. 5.

Fig. 8 is a third topological structural view of a power conversion device having a function of suppressing common mode noise according to the present invention.

9 is a diagram of an equivalent common mode noise model of the topology shown in FIG.

Figure 10a is a voltage spectrum diagram.

Figure 10b is another voltage spectrum diagram.

Figure 11 is a fourth topological structural view of a power conversion apparatus having a function of suppressing common mode noise according to the present invention.

Figure 12 is a topological view of an electromagnetic interference filter.

Figure 13 is a topological view of another electromagnetic interference filter.

Fig. 14 is a view showing an application topology of the power conversion device having the function of suppressing common mode noise.

Fig. 15 is a view showing another application topology of the power conversion device having the function of suppressing common mode noise.

Fig. 16 is still another application topology diagram of the power conversion device having the function of suppressing common mode noise.

Fig. 17 is a diagram showing still another application topology of the power conversion device having the function of suppressing common mode noise.

[0031]

Hereinafter, various embodiments of a power conversion device having a function of suppressing common mode noise of the present invention will be specifically described with reference to the drawings. For the sake of clarity, details of various embodiments are set forth in the following description. However, it should be understood that the details of these embodiments should not be taken to limit the application.

[0032]

Please refer to FIG. 4 and FIG. 5 simultaneously, which are respectively a first and second topology structure of a power conversion device having a function of suppressing common mode noise. As shown in FIG. 4, the topology of the power conversion device 1 (hereinafter referred to as the power conversion device 1) having the function of suppressing common mode noise mainly includes: a ground terminal GND, a power conversion unit 11, and a DC bus capacitor unit. CB0, a filter capacitor unit 12, a filter inductor unit 13, and a compensation circuit 14. As shown in FIG. 5, the power conversion unit 11 is a two-level three-phase power converter, and has a first DC terminal P, a second DC terminal Q, a first AC terminal A, and a second AC terminal B. And a third AC terminal C; wherein, since the first DC terminal P and the second DC terminal Q are not connected to an external electrical device, the DC bus capacitor unit CB0 is coupled to the first DC terminal P. Between the second DC terminal Q and the second DC terminal Q. In this case, it must be particularly noted that among any possible engineering applications, the power conversion unit 11 can be coupled to a capacitor, a DC to an alternating current (DC) through its first DC terminal P and the second DC terminal Q. -AC) Rectifier unit, or a battery.

[0033]

Referring again to FIG. 5, and referring to the topology of the power conversion unit 11 shown in FIG. 6, the power conversion unit 11 is a three-level power conversion unit. In practical applications, the power conversion unit 11 can also be a multi-level three-phase power conversion unit or other multi-level power converter; wherein the DC bus capacitor unit CB0 is divided into a first bus capacitor CB1 and A second bus capacitor CB2. As shown, the first bus capacitor CB1 is coupled between the first DC terminal P and the DC bus midpoint O, and the second bus capacitor CB2 is coupled to the second DC terminal Q and the DC bus midpoint. Between O.

[0034]

The power conversion device 1 of the present invention is further described. The filter capacitor unit 12 includes a first filter capacitor Cx1, a second filter capacitor Cx2 and a third filter capacitor Cx3. As shown in FIG. 5, one end of the first filter capacitor Cx1, the second filter capacitor Cx2, and the third filter capacitor Cx3 is coupled to an external electrical device 2; in particular, the electrical device 2 is a The electrical device 2 of the phase terminal, such as a power grid, a motor, and a non-linear load; therefore, one end of each of the first filter capacitor Cx1, the second filter capacitor Cx2, and the third filter capacitor Cx3 is coupled to the electrical device 2, respectively. a first phase terminal Ua, a second phase terminal Ub and a third phase terminal Uc; and the other ends of the first filter capacitor Cx1, the second filter capacitor Cx2 and the third filter capacitor Cx3 are connected to each other to form a common End N. In addition, a Line Impedance Stabilization Network (LISN) 15 is coupled between the electrical device 2 and the filter capacitor unit 12 for conducting electromagnetic conduction as the power conversion device having the function of suppressing common mode noise. Auxiliary equipment during interference testing.

[0035]

As shown in FIG. 5, the filter inductor unit 13 includes: a first main winding inductance LA, a first auxiliary winding inductance LA', a second main winding inductance LB, a second auxiliary winding inductance LB', and a third main a winding inductance LC and a third auxiliary winding inductance LC'; wherein the first main winding inductance LA has a low frequency end coupled to the first phase terminal Ua of the electrical device 2, and is coupled to the power conversion unit 11 a high frequency end of the first AC terminal A. Corresponding to the first main winding inductance LA, the first auxiliary winding inductance LA' also has a low frequency end and a high frequency end, and the low frequency end of the main winding is the same name end, which is defined as the low frequency band of the auxiliary winding, and the height of the main winding The frequency ends are defined by the same name as the high frequency band of the auxiliary winding. As shown in the figure, one end of the point is the same name end of the auxiliary winding inductance and the main winding inductance, that is, the first auxiliary winding inductance LA' The low frequency end and the other end are high frequency ends, and the low frequency end of the first auxiliary winding described in the item is coupled to the common terminal N. Moreover, the second main winding inductance LB has a low frequency end coupled to the second phase terminal Ub of the electrical device 2, and a high frequency end coupled to the second AC terminal B of the power conversion unit 11; The second auxiliary winding inductance LB' also has a low frequency end and a high frequency end. As shown in the figure, one end of the dotted point is the same name end of the auxiliary winding inductance and the main winding inductance, so the second auxiliary winding inductance LB' is dotted. The end is its low frequency end and the other end is the high frequency end. Furthermore, the third main winding inductance LC also has a low frequency end and a high frequency end, wherein the low frequency end of the third main winding inductance LC is coupled to the third phase terminal Uc of the electrical device 2, and the high frequency end thereof The third AC terminal C is coupled to the third AC terminal C. The third auxiliary winding inductance LC' also has a low frequency end and a high frequency end. As shown in the figure, one end of the dotted point is the same name end of the auxiliary winding inductance and the main winding inductance, so the third auxiliary winding inductance LC' with a dotted end It is the low frequency end and the other end is the high frequency end.

[0036]

In the present invention, the compensation line 14 is mainly formed by the first auxiliary winding inductance LA', the second auxiliary winding inductance LB', the third auxiliary winding inductance LC', and a compensation unit 141; The three auxiliary windings are connected in series with the high frequency end to form a compensation branch. One end of the series branch is composed of the high frequency end of the compensation branch, and the other end is the low frequency end of the compensation branch. As shown in FIG. 5, the low frequency end of the compensation branch is connected to the common terminal N of the filter capacitor unit 12, and the high frequency end of the compensation branch is coupled to the ground GND. The present invention does not particularly limit the form of the compensation unit 141. Therefore, the compensation unit 141 may be a compensation capacitor Ccomp, a compensation inductor Lcomp, a compensation resistor, a series combination of the above, or a series combination of the above. Please refer to FIG. 5 and FIG. 7 at the same time. FIG. 7 is an equivalent common mode noise model of the topology shown in FIG. 5. As shown in FIG. 5, the compensation unit 141 is formed by a compensation inductor Lcomp and a compensation capacitor Ccomp; therefore, the topology of FIG. 5 can be simplified to the equivalent common mode noise model of FIG. In the equivalent common mode noise model of FIG. 7, Z _LISN is the equivalent resistance (impedance) of the power supply impedance stabilization network 15 shown in FIG. 5, N is the common terminal, and M is the internal of the filter inductor unit 13. The mutual inductance of the main winding inductance and the three auxiliary winding inductances, L is the inductance of the three main windings inside the filter inductor unit 13, and L' is the inductance of the three auxiliary windings inside the filter inductor unit 13.

[0037]

Continuing to refer to both FIG. 5 and FIG. 7 simultaneously. In FIG. 5, u _AO , u _{BO ,} and u _CO are respectively represented as voltages between the first alternating current terminal A, the second alternating current terminal B, and the third alternating current terminal C and the midpoint O of the direct current bus. Ucomp is represented as a compensation voltage formed by the three auxiliary winding inductances (LA1', LA2', and LA3') of the filter inductor unit 13; and C1a, C1b, and C1c in Fig. 5 are three AC terminals, respectively (A, B and C) The distributed capacitance to ground, and Co is the distributed capacitance of point O to ground in the DC bus. In the topology of Figure 5, the hopping voltages (u _AO , u _{BO ,} and u _CO ) generate displacement currents on the distributed capacitances (C1a, C1b, and C1c), and the displacement current flows into the ground to form a common mode current (ie, , common mode noise). In addition, corresponding to FIG. 5, Ccm of FIG. 7 is an equivalent common mode capacitor, which is the total capacitance of the four distributed capacitors (C1a, C1b, C1c, and C0).

[0038]

As described above, according to the equivalent model of FIG. 7, it can be found that if the inductance Lcomp=M-3L' of the compensation inductance, 3L'-M+Lcomp=0 is made; thus, the compensation line 14 can be Is equivalent to a compensation capacitor Ccomp, so that the compensation capacitor Ccomp is used as a Y capacitor (ie, CY), while the mutual inductance M can be equalized for use as a common mode inductor (ie, LCM), while the Y capacitor and the common mode The inductor forms an equivalent common mode filter. In practical applications, as long as Lcomp < 2 (M-3L'), it can have a significant effect on the equivalent common mode filter.

[0039]

In addition, as shown in FIG. 8, a third topology of the power conversion apparatus having the function of suppressing common mode noise of the present invention is shown. Compared to the topology of FIG. 5, the topology of FIG. 8 is a compensation capacitor Ccomp as the compensation unit 141. Also, the topology of the power conversion device of FIG. 8 can be equivalent to the equivalent common mode noise model as shown in FIG. In the topology shown in FIG. 8, the turns ratio n of the main winding inductance and the auxiliary winding inductance in the filter inductor unit 13 is 3:1; thus, the inductance of the three main windings inside the filter inductor unit 13 is made. The total inductance L = 9L', and the mutual inductance of the three main winding inductances and the three auxiliary winding inductances M = 3L'. Since Lcomp = M-3L', it is known from the calculation that Lcomp = 0. That is to say, in the topology of the power conversion device 1 of Fig. 8, it is not necessary to use a compensation inductor.

[0040]

According to the above description, since L/3-M=0, as shown by the curve 3 in FIG. 3, such a design can greatly suppress the common mode noise at the resonance frequency f0 of the power converter. . In this case, it must be additionally noted that in practical engineering applications, since the coupling between the main winding inductance and the auxiliary winding inductance inside the filter inductor unit 13 cannot reach the theoretical value of 1; for this reason, the design of the present invention has When the power conversion device 1 suppressing the common mode noise function, the turns ratio n of the main winding inductance and the auxiliary winding inductance can be allowed to be between 3:1.3 and 3:0.7, and the preferred turns ratio n is 3: 1.

[0041]

The power conversion device 1 shown in FIG. 8 can suppress the common mode noise, and the topology can be implemented by the analog software, and the voltage value of the power supply impedance stabilization network (LISN) 15 can be measured at different frequencies. The simulation results are shown in Fig. 10a; the topology of the existing power conversion device shown in Fig. 1 is implemented by the simulation software, and the voltage value of the power supply impedance stabilization network (LISN) is measured at different frequencies. The results of the measurement are shown in Figure 10b. Comparing Fig. 10a with Fig. 10b, it can be clearly seen that the power conversion device 1 shown in Fig. 8 has a better common mode noise suppression effect in the frequency range of 30 kHz and also reduces resonance occurring in the frequency range of 260 kHz or more.

[0042]

In addition to the topology of the power conversion device having the function of suppressing common mode noise of the present invention shown in FIG. 3, FIG. 5, and FIG. 8, in the actual engineering application, the power conversion device having the function of suppressing common mode noise of the present invention There are other extended topologies. Please refer to FIG. 11 , which is a fourth topology structure of the power conversion device with the function of suppressing common mode noise according to the present invention; wherein the topology shown in FIG. 11 is coupled by an EMI filter 17 . This is completed between the filter capacitor unit 12 and the electric device 2 in the power conversion device 1 shown in FIG. Also, the electromagnetic interference filter 17 may be a differential mode filter as shown in FIG. 12 or a common mode filter as shown in FIG.

[0043]

According to the above description, if the differential mode filter is used as the electromagnetic interference filter 17, it includes: a first differential mode filter inductor LDM1, one end of which is coupled to the first phase terminal Ua, and the other end of which is The second differential mode filter inductor LDM2 is coupled to the second phase terminal Ub, and the other end thereof is coupled to the second filter capacitor Cx2; a differential mode filter inductor LDM3, one end of which is coupled to the third phase terminal Uc, and the other end of which is coupled to the third filter capacitor Cx3; a first differential mode filter capacitor Cxx1, one end of which is coupled to the a first differential mode filter inductor LDM1, the other end of which is coupled to the second differential mode filter inductor LDM2; a second differential mode filter capacitor Cxx2, one end of which is coupled to the second differential mode filter inductor LDM2, and The other end is coupled to the third differential mode filter inductor LDM3, and a third differential mode filter capacitor Cxx3, one end of which is coupled to the first differential mode filter inductor LDM1, and the other end of which is coupled to the The third differential mode filter inductor LDM3.

[0044]

Moreover, if the common mode filter is used as the EMI filter 17, it includes: a first common mode filter inductor LCM1, one end of which is coupled to the first phase terminal Ua, and the other end of which is coupled to The first filter capacitor Cx1; a second common mode filter inductor LCM2, one end of which is coupled to the second phase terminal Ub, and the other end of which is coupled to the second filter capacitor Cx2; a third common mode filter The inductor LCM3 has one end coupled to the third phase terminal Uc, and the other end of which is coupled to the third filter capacitor Cx3; a first common mode filter capacitor CY1, one end of which is coupled to the third common a mode filter inductor LCM3, and the other end of the module is coupled to the ground GND; a second common mode filter capacitor CY2, one end of which is coupled to the second common mode filter inductor LCM2, and the other end of which is coupled to The grounding terminal GND; and a third common mode filter capacitor CY3, one end of which is coupled to the first common mode filter inductor LCM1, and the other end of which is coupled to the ground terminal GND.

[0045]

Thus, through the above-described complete description, the topology of various practical applications of the power conversion apparatus having the function of suppressing common mode noise of the present invention and related technical features have been clearly described. Next, the application surface of the power conversion device of the present invention will be further described below. As shown in FIG. 14, the power conversion unit 11 is coupled to the second DC terminal Q via a first DC terminal P and a second power conversion unit 11a. The second power conversion unit 11a is coupled to the second power conversion unit 11a. a motor 2b, three AC terminals (A, B and C) of the power conversion device 1 are coupled to an external power grid 2a, wherein the second power conversion unit 11a can be a DC-AC inverter unit or AC to DC rectification unit, the power conversion device can be applied to a motor drive system or a wind power generation system. Referring to the topology of the power conversion device 1 shown in FIG. 15, the power conversion unit 11 is coupled to the second DC terminal Q via its first DC terminal P and a second power conversion unit 11a. The second power conversion is performed. The unit 11a is coupled to the external power grid 2a, and the three AC terminals (A, B and C) of the power conversion device 1 are coupled to the motor 2b, wherein the second power conversion unit 11a can be a DC to AC (DC-AC) inverse A variable unit or an alternating current to direct current rectifying unit, the power conversion device can be applied to a motor drive system or a motor side of a wind power generation system.

[0046]

Please refer to the topology of the power conversion device 1 shown in FIG. 16 , wherein the first DC terminal P and the second DC terminal Q of the power conversion unit 11 are not connected to external electrical devices, and thus the bus bar capacitance is always The unit CB0 is coupled between the first DC terminal P and the second DC terminal Q; oppositely, between the three AC terminals Q of the power conversion unit 11, oppositely, three AC terminals of the power conversion unit 11 (A, B and C) are simultaneously coupled to a grid 2a and a non-linear load 2c. Finally, please refer to the topology of the power conversion device 1 shown in FIG. 17, wherein the power conversion unit 11 is coupled to one battery 2d through its first DC terminal P and the second DC terminal Q; and, the power conversion unit The three AC terminals (A, B and C) of 11 are coupled to a grid 2a.

[0047]

Thus, the above describes the topology of the power conversion apparatus having the function of suppressing common mode noise and an application level thereof according to an embodiment of the present invention, and it can be seen from the above that the present invention has at least one of the following advantages:

[0048]

1. The power conversion device with the function of suppressing common mode noise proposed by the present invention, the main technical feature is the topology design of the filter inductor unit 13 and the compensation circuit 14; wherein, three sets of main winding inductance and three sets of auxiliary winding inductance The filter inductor unit is configured such that the power conversion unit 11 can be coupled to the three phase terminals of the external electrical device through the three sets of main winding inductances; at the same time, the three sets of auxiliary winding inductances are used to compensate, for example, the compensation capacitor Ccomp. The unit 141 is configured to constitute the compensation circuit 14, so that the engineer can significantly and effectively suppress the common mode noise at the resonant frequency of the power converter by selecting an appropriate turns ratio of the main winding inductance and the auxiliary winding inductance. .

[0049]

2. According to the above first point, and because the three sets of auxiliary winding inductances are mainly used to guide the common mode current (common mode noise) to the ground GND, the three sets of auxiliary windings can be wound out with relatively thin wires. Inductance, this way can also effectively save the size and manufacturing cost of the common mode filter.

[0050]

It is apparent to those skilled in the art that various changes and modifications can be made in the present application without departing from the spirit and scope of the application. Therefore, the present application is intended to cover various modifications and variations of the present invention as long as they fall within the scope of the claims and their equivalents.

1‧‧‧Power conversion device with suppression of common mode noise

11‧‧‧Power conversion unit

12‧‧‧Filter capacitor unit

13‧‧‧Filter Inductance Unit

14‧‧‧Compensation line

141‧‧‧Compensation unit

15‧‧‧Power impedance stable network

2‧‧‧Electrical installation

A‧‧‧First AC terminal

B‧‧‧Second AC terminal

C‧‧‧third AC terminal

Cx1‧‧‧first filter capacitor

Cx2‧‧‧second filter capacitor

Cx3‧‧‧ third filter capacitor

N‧‧‧ public end

P‧‧‧First DC terminal

Q‧‧‧second DC terminal

CB0‧‧‧DC bus capacitor unit

Ccomp‧‧‧compensation capacitor

Lcomp‧‧‧Compensated inductance

LA‧‧‧First main winding inductance

LA’‧‧‧First auxiliary winding inductance

LB‧‧‧Second main winding inductance

LB’‧‧‧Second auxiliary winding inductance

LC‧‧‧ Third main winding inductance

LC'‧‧‧ Third auxiliary winding inductance

Ua‧‧ first phase terminal

Ub‧‧‧Second phase terminal

Uc‧‧‧ third phase terminal

GND‧‧‧ ground terminal

Claims (18)

[Item 1] A power conversion device with a function of suppressing common mode noise, comprising:
a ground terminal;
a power conversion unit having a first DC terminal, a second DC terminal, a first AC terminal, a second AC terminal, and a third AC terminal;
a DC bus capacitor unit coupled between the first DC terminal and the second DC terminal;
a filter capacitor unit includes a first filter capacitor, a second filter capacitor, and a third filter capacitor, wherein each of the first filter capacitor, the second filter capacitor, and the third filter capacitor are respectively coupled a first phase terminal, a second phase terminal and a third phase terminal, wherein the other ends of the first filter capacitor, the second filter capacitor and the third filter capacitor are connected to each other as a common terminal; and a filter An inductor unit, the filter inductor unit includes:
a first main winding inductor having a first main winding low frequency end and a first main winding high frequency end, wherein the first main winding low frequency end is coupled to the first phase terminal and the third filter capacitor, The first main winding high frequency end is coupled to the first AC terminal;
a first auxiliary winding inductor inductively coupled to the first main winding and having a first auxiliary winding low frequency end and a first auxiliary winding high frequency end, wherein the first auxiliary winding low frequency end is coupled to the common end;
a second main winding inductor having a second main winding low frequency end and a second main winding high frequency end, wherein the second main winding low frequency end is coupled to the second phase terminal and the second filter capacitor, The second main winding high frequency end is coupled to the second AC terminal;
a second auxiliary winding inductor is inductively coupled to the second main winding, and has a second auxiliary winding low frequency end and a second auxiliary winding high frequency end, wherein the second auxiliary winding low frequency end is coupled to the first Auxiliary winding high frequency end;
a third main winding inductor having a third main winding low frequency end and a third main winding high frequency end, wherein the third main winding low frequency end is coupled to the third phase terminal and the first filter capacitor, The third main winding high frequency end is coupled to the third alternating current terminal; and a third auxiliary winding inductance is inductively coupled to the third main winding and has a third auxiliary winding low frequency end and a third auxiliary winding high The frequency end, wherein the low frequency end of the third auxiliary winding is coupled to the high frequency end of the second auxiliary winding, and the high frequency end of the third auxiliary winding is coupled to the ground end. [Item 2] The power conversion device with the function of suppressing the common mode noise according to the first aspect of the patent application, further comprising: a compensation unit, one end of the compensation unit is coupled to the high frequency end of the third auxiliary winding, The other end of the compensation unit is coupled to the ground. [Item 3] A power conversion device having a function of suppressing common mode noise according to claim 2, wherein the compensation unit is a compensation capacitor, a compensation inductor, a compensation resistor, a series combination of the above, and the foregoing Combination in series. [Item 4] The power conversion device with the function of suppressing common mode noise according to the second aspect of the patent application is characterized in that the compensation unit is composed of a compensation inductor and a compensation capacitor in series, and the inductance Lcomp of the compensation inductor meets the following The calculation formula is: Lcomp<2(M-3L'); wherein, M is the mutual inductance of the three main winding inductances and the three auxiliary winding inductances inside the filter inductor unit, and L' is three inside the filter inductor unit The inductance of the auxiliary winding inductance. [Item 5] A power conversion device having a function of suppressing common mode noise according to the fourth aspect of the invention is characterized in that the inductance Lcomp of the compensation inductance satisfies the following calculation formula: Lcomp = M-3L'. [Item 6] The power conversion device with the function of suppressing common mode noise according to claim 1, wherein the first main winding inductance has a turns ratio of the first auxiliary winding inductance, and the second main winding inductance The turns ratio of the second auxiliary winding inductance and the turns ratio of the third main winding inductance to the third auxiliary winding inductance are between 3:1.3 and 3:0.7. [Item 7] The power conversion device with the function of suppressing common mode noise according to claim 6 is characterized in that: the turns ratio of the first main winding inductance to the first auxiliary winding inductance, and the second main winding inductance The turns ratio of the second auxiliary winding inductance and the turns ratio of the third main winding inductance to the third auxiliary winding inductance are both 3:1. [Item 8] A power conversion device having a function of suppressing common mode noise according to claim 1 of the patent application, characterized in that the power conversion unit is a two-level power converter, a three-level power converter or other multi-level Power converter. [Item 9] The power conversion device with the function of suppressing common mode noise according to the first aspect of the invention is characterized in that the first DC terminal and the second DC terminal are coupled to a first electrical device. [Item 10] A power conversion device having a function of suppressing common mode noise according to claim 9 of the patent application, characterized in that the first electrical device is a power grid, a motor or an energy storage unit. [Item 11] The power conversion device with the function of suppressing common mode noise according to claim 10, further comprising a second power conversion unit coupled to the first electrical device and the first DC terminal And between the second DC terminals. [Item 12] The power conversion device with the function of suppressing common mode noise according to claim 11 is characterized in that the second power conversion unit is an alternating current to direct current rectifying unit or flows to the alternating current inverting unit. [Item 13] The power conversion device with the function of suppressing common mode noise according to claim 1, wherein the first phase terminal, the second phase terminal and the third phase terminal are coupled to a second electrical device. . [Item 14] A power conversion device having a function of suppressing common mode noise according to claim 13 of the patent application, characterized in that the second electrical device is a power grid or a motor. [Item 15] The power conversion device with the function of suppressing common mode noise according to claim 13 of the patent application, further comprising an electromagnetic interference filter coupled to the filter capacitor unit and the first phase terminal, the first Between the two-phase terminal and the third phase terminal. [Item 16] A power conversion device having a function of suppressing common mode noise according to claim 15 of the patent application, characterized in that the electromagnetic interference filter comprises:
a first EMI filter inductor having one end coupled to the first phase terminal and the other end coupled to the first filter capacitor;
a second EMI filter inductor having one end coupled to the second phase terminal and the other end coupled to the second filter capacitor;
a third EMI filter inductor having one end coupled to the third phase terminal and the other end coupled to the third filter capacitor;
a first electromagnetic interference filter capacitor, one end of which is coupled to the first electromagnetic interference filter inductor, and the other end of which is coupled to the second electromagnetic interference filter inductor;
a second electromagnetic interference filter capacitor, one end of which is coupled to the second electromagnetic interference filter inductor, and the other end of which is coupled to the third electromagnetic interference filter inductor; and a third electromagnetic interference filter capacitor, one end of which is coupled to The first electromagnetic interference filter inductor is coupled to the third electromagnetic interference filter inductor. [Item 17] A power conversion device having a function of suppressing common mode noise according to claim 15 of the patent application, characterized in that the electromagnetic interference filter comprises:
a first EMI filter inductor having one end coupled to the first phase terminal and the other end coupled to the first filter capacitor;
a second EMI filter inductor having one end coupled to the second phase terminal and the other end coupled to the second filter capacitor;
a third EMI filter inductor having one end coupled to the third phase terminal and the other end coupled to the third filter capacitor;
a first electromagnetic interference filter capacitor, one end of which is coupled to the third electromagnetic interference filter inductor, and the other end of which is coupled to the ground end;
a second electromagnetic interference filter capacitor, one end of which is coupled to the second electromagnetic interference filter inductor, and the other end of which is coupled to the ground end; and a third electromagnetic interference filter capacitor, one end of which is coupled to the first electromagnetic Interference with the filter inductor, and the other end of the filter is coupled to the ground. [Item 18] A power conversion device having a function of suppressing common mode noise according to claim 1 is characterized in that the power conversion device is a three-phase three-wire power conversion device.