CN108768195A - Power circuit, power module and current transformer - Google Patents
Power circuit, power module and current transformer Download PDFInfo
- Publication number
- CN108768195A CN108768195A CN201810696727.6A CN201810696727A CN108768195A CN 108768195 A CN108768195 A CN 108768195A CN 201810696727 A CN201810696727 A CN 201810696727A CN 108768195 A CN108768195 A CN 108768195A
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- Prior art keywords
- circuit
- bridge arm
- busbar
- capacitance
- electrically connected
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Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
- H02M7/4835—Converters with outputs that each can have more than two voltages levels comprising two or more cells, each including a switchable capacitor, the capacitors having a nominal charge voltage which corresponds to a given fraction of the input voltage, and the capacitors being selectively connected in series to determine the instantaneous output voltage
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
- H02M7/487—Neutral point clamped inverters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
- H02M7/5387—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
- H02M7/53871—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration with automatic control of output voltage or current
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
Abstract
The embodiment of the present application provides a kind of power circuit, power module and current transformer, the power circuit：Three level bridge arm modules and busbar support capacitance module, three level bridge arm modules include at least one bridge arm；The positive direct current terminal of bridge arm is electrically connected by the first connection circuit with busbar support capacitance module；Negative DC terminal of bridge arm is electrically connected by the second connection circuit with busbar support capacitance module；The neutral terminal of bridge arm connects circuit by third respectively, the 4th connection circuit is electrically connected with busbar support capacitance module；The angle that first connection circuit connect circuit with third is less than preset angle threshold, and/or, the angle that the second connection circuit connect circuit with the 4th is less than preset angle threshold.In the embodiment of the present application, electric current inputs path and circuit output path is almost mutually parallel and current direction is opposite so that the magnetic field of two-way electric current largely offsets each other, and can reduce the parasitic inductance on electric current carrying pathway, can promote stability when bridge arm switching.
Description
Technical field
This application involves converter topology fields, specifically, this application involves a kind of power circuit, power module and changes
Flow device.
Background technology
With the development of power electronic technique, in powerful grid type equipment such as wind electric converter, for unsteady flow
The promotion of device transfer efficiency and the reduction of cooling system cost gradually start to apply T-type three-level topology.Due to being packaged with
The IGBT (Insulated Gate Bipolar Transistor, insulated gate bipolar transistor) of three level bridge arm of complete T-type
Type of modules is less, is generally spliced into T-NPC (T type- using half-bridge IGBT module and common emitter IGBT module in the market
Neutral Point Clamped, T-type neutral-point-clamped type) three level bridge arms solution.In this scenario, half-bridge
IGBT module is connected between the positive and negative terminal of DC bus, referred to as non-zero level bridge arm, common emitter IGBT module and DC bus
Neutral end is electrically connected, referred to as zero level bridge arm.
Due to carrying out being spliced to form T-NPC bridge arms using independent two kinds of IGBT modules, in the T-NPC bridge arm courses of work
In, when electric current is switched to zero level bridge arm from non-zero level bridge arm and works, stray inductance on current switching path (or it is parasitic
Inductance) generate back-emf can be added on DC bus-bar voltage, cause the voltage stress of IGBT switching processes to improve, IGBT pairs
It is very sensitive in voltage stress, it is therefore desirable to reduce the stray inductance on current switching path as far as possible.
Invention content
This application provides a kind of power circuit, power module and current transformers, for solving electricity existing in the prior art
Flow the larger technical problem of stray inductance on toggle path.
In a first aspect, this application provides a kind of power circuits, including：Three level bridge arm modules and busbar Support Capacitor mould
Block, three level bridge arm modules include at least one bridge arm；
The positive direct current terminal of bridge arm is electrically connected by the first connection circuit with busbar support capacitance module；The negative direct current of bridge arm
Terminal is electrically connected by the second connection circuit with busbar support capacitance module；The neutral terminal of bridge arm connects electricity by third respectively
Road, the 4th connection circuit are electrically connected with busbar support capacitance module；
The angle that first connection circuit connect circuit with third is less than preset angle threshold, and/or, the second connection circuit
The angle that circuit is connect with the 4th is less than preset angle threshold.
Second aspect, this application provides a kind of power modules, including：Stack bus bar and the application first aspect institute
The power circuit shown；
Three level bridge arm modules and busbar support capacitance module are set on stack bus bar；
Three level bridge arm modules are set to first area；
Busbar support capacitance module is set to the second area of first area face；
Stack bus bar includes：The second mother for being provided with the first busbar of the first connection circuit, being provided with the second connection circuit
Row and the third busbar for being provided with third connection circuit and the 4th connection circuit.
The third aspect, this application provides a kind of current transformers, including power module shown in the application second aspect.
Technical solution provided by the embodiments of the present application, at least has the advantages that：
By using connection circuit by the electrical connection corresponding with busbar support capacitance module of three level bridge arm modules, and make three electricity
The angle that the electric current input path of flat bridge arm module and current out path are formed is less than preset angle threshold so that electric current is defeated
Enter that path and circuit output path are almost mutually parallel and current direction is opposite so that the magnetic field of two-way electric current largely mutually offsets
Disappear, and then the stray inductance on electric current carrying pathway is made to be reduced to a lower numerical value, substantially reduces three level bridge arm moulds
Generated back-emf, the power electric component greatly reduced in bridge arm were switching when switching between different bridge arms in block
Voltage stress in journey can promote the stability of the power electric component in bridge arm, to promote entire three level bridge arm
The stability of module.
The additional aspect of the application and advantage will be set forth in part in the description, these will become from the following description
It obtains obviously, or recognized by the practice of the application.
Description of the drawings
In order to more clearly explain the technical solutions in the embodiments of the present application, institute in being described below to the embodiment of the present application
Attached drawing to be used is needed to be briefly described.
Fig. 1 is a kind of existing circuit theory schematic diagram of three-level topology circuit；
Fig. 2 is the circuit theory schematic diagram of a kind of existing single-phase three-level topology circuit and load connection；
Fig. 3 is the circuit theory schematic diagram of a kind of existing three-phase tri-level topological circuit and load connection；
Fig. 4 is a kind of structure and current path schematic diagram of single-phase power module provided by the embodiments of the present application；
Fig. 5 is the structure and current path schematic diagram of another single-phase power module provided by the embodiments of the present application；
Fig. 6 is the circuit theory schematic diagram of single-phase power module shown in fig. 5；
Fig. 7 is a kind of structure and current path schematic diagram of two-phase power module provided by the embodiments of the present application；
Fig. 8 is the circuit theory schematic diagram of two-phase power module shown in Fig. 7；
Fig. 9 is a kind of structure and current path schematic diagram of three phase power module provided by the embodiments of the present application.
Specific implementation mode
Embodiments herein is described below in detail, examples of the embodiments are shown in the accompanying drawings, wherein from beginning to end
Same or similar label indicates same or similar element or element with the same or similar functions.Below with reference to attached
The embodiment of figure description is exemplary, and is only used for explaining the application, and cannot be construed to the limitation to the application.
Those skilled in the art of the present technique are appreciated that unless expressly stated, singulative " one " used herein, " one
It is a " and "the" may also comprise plural form.It is to be further understood that wording " the packet used in the description of the present application
Include " refer to there are the feature, integer, step, operation, element and/or component, but it is not excluded that presence or addition one or
Other multiple features, integer, step, operation, element, component and/or their group.It should be understood that when we claim element by " even
Connect " or when " coupled " to another element, it can be directly connected or coupled to other elements, or there may also be cental elements
Part.In addition, " connection " used herein or " coupling " may include being wirelessly connected or wirelessly coupling.Wording used herein " and/
Or " include that the whole of one or more associated list items or any cell are combined with whole.
To keep the purpose, technical scheme and advantage of the application clearer, below in conjunction with attached drawing to the application embodiment party
Formula is described in further detail.
First to this application involves several nouns be introduced and explain：
Three level：One kind can export the power electronics skill that direct current positive (DC+), neutral point (NP), direct current bear (DC-) current potential
Art.
T-NPC (T type-Neutral Point Clamped, T-type neutral-point-clamped type) three-level topology circuit, letter
Claim T-type NPC, one kind of three-level topology.
IGBT (Insulated Gate Bipolar Transistor, insulated gate transistor) is a kind of controllable progress
The device of high-speed switch action.
Stack bus bar：One kind reducing the technology of DC link stray inductance by pressing together DC master row.
Stray inductance：Conductor itself parasitic parameter, also referred to as parasitic inductance.
DC support capacitance：In power electronic technique, support DC bus-bar voltage is generally played, exchange side ripple is provided
Electric current provides the IGBT effects of switching transients energy.
Present inventor has found that presently, there are a kind of T-NPC three-level topologies electricity when realizing the purpose of the application
Road, circuit theory is as shown in Figure 1, with the bridge arm laterally drawn in three level bridge arms, capacitance group C1 and capacitance group C2, Fig. 1
For transverse tube (zero level bridge arm), the bridge arm longitudinally drawn is vertical tube (non-zero level bridge arm), capacitance group C1 and capacitance group C2 series connection
DC bus-bar voltage, the midpoint of capacitance group C1 and C2 is supported to be connected to neutral point (NP), the other both ends point of capacitance group C1 and C2
It is not connected to direct current positive (DC+) and direct current bears (DC-).
DC support capacitance group C1 and C2 is constantly in charge or discharge state in the switch periods of IGBT.Work as direct current
When the C1 electric discharges of Support Capacitor group, exists from DC+ and flow into three level bridge arms, the access of capacitance group C1 is flowed out to from NP；When direct current branch
When supportting capacitance group C1 chargings, exists from NP and be flowed into three level bridge arms, the access of capacitance group C1 is flowed out to from DC+.When direct current branch
When supportting capacitance group C2 electric discharges, exists from NP and flow into three level bridge arms, the access of capacitance group C2 is flowed out to from DC-；Work as DC support
When capacitance group C2 chargings, exists from DC- and be flowed into three level bridge arms, the access of capacitance group C2 is flowed out to from NP.
When above-mentioned three-level topology circuit, which connects, to be loaded, circuit theory is as shown in Fig. 2, when the close sides NP in transverse tube
When IGBT is connected, current path, as the discharge current flow direction of capacitance group C2 shown in dotted line direction in Fig. 2 are formed.Root
According to the current path principle of foregoing three-level topology circuit, it will be appreciated by those skilled in the art that Fig. 2 in the case of other
Shown in circuit current direction, details are not described herein again.
When above-mentioned three-level topology circuit has three-phase bridge arm and connection load, circuit theory is as shown in figure 3, three-phase
Bridge arm refers to A, B and C three-phase shown in Fig. 3.When the IGBT conductings for exchanging output point or more in the vertical tube of A phase bridge arms, and B phase bridges
When in the transverse tube of arm close to the IGBT of the sides AC conductings, current path as shown in phantom in Figure 3 is formed, capacitance group C1 passes through at this time
The current path discharges.According to the current path principle of foregoing three-level topology circuit, those skilled in the art can be with
Understand it is other in the case of circuit shown in Fig. 3 current direction, details are not described herein again.
On the current path of above-described each circuit, current path is longer, and existing stray inductance is larger, due to
IGBT is in quick on off state, and current path is also quickly switching, and the presence of stray inductance will inhibit the fast of electric current
Speed variation, while a reverse potential is produced, it is added on the voltage of DC capacitor group, then causes the electricity of IGBT shutdown moments
Pressure increases, and causes additional shutdown stress.
Power circuit, power module and current transformer provided by the present application, it is intended to solve the technical problem as above of the prior art.
How the technical solution of the application and the technical solution of the application are solved with specifically embodiment below above-mentioned
Technical problem is described in detail.These specific embodiments can be combined with each other below, for same or analogous concept
Or process may repeat no more in certain embodiments.Below in conjunction with attached drawing, embodiments herein is described.
Embodiment one
The embodiment of the present application provides a kind of power circuit, as shown in figure 4, the power circuit includes：Three level bridge arm moulds
Block and busbar support capacitance module, three level bridge arm modules include at least one bridge arm 10.The bridge arm 10 includes common emitter circuit
12 and half-bridge circuit 11.
The positive direct current terminal DC+ of each bridge arm 10 is electrically connected by the first connection circuit 21 with busbar support capacitance module
It connects；The sub- DC- of negative DC terminal of each bridge arm 10 is electrically connected by the second connection circuit 22 with busbar support capacitance module；Each
The neutral terminal NP of bridge arm 10 connects the connection circuit 24 of circuit the 23, the 4th by third respectively and is electrically connected with busbar support capacitance module
It connects.
According to the difference of busbar support capacitance module working condition, the first connection circuit 21, second connects circuit 22, third
It connects circuit 23 and the 4th and connects circuit 24, can be used as electric current input path or the electric current output road of three level bridge arm modules
Diameter.
In the embodiment of the present application, the angle that the first connection circuit 21 connect circuit 23 with third is less than preset angle threshold
Value, and/or, the angle that the second connection circuit 22 connect circuit 24 with the 4th is less than preset angle threshold.Wherein, angle threshold
It can be set according to actual demand.
According to stray inductance theory, when the angle between two electric current carrying pathways is smaller, magnetic field can be largely
Cancel out each other, and then the stray inductance of electric current carrying pathway is made to be substantially reduced；And angle is smaller, magnetic field cancellation is more apparent, electricity
The stray inductance in steaming transfer path is lower.
The embodiment of the present application one additionally provides alternatively possible realization method, with reference to figure 4-6, is specifically described as follows：
Optionally, power circuit provided by the embodiments of the present application is T-NPC three-level topology circuits.
Optionally, bridge arm 10 includes the half-bridge circuit 11 and common emitter circuit 12 of electrical connection；The first end of half-bridge circuit 11
For the positive direct current terminal of affiliated bridge arm 10, second end is negative DC terminal of affiliated bridge arm 10；The first end of common emitter circuit 12
It is electrically connected with the ac output end of half-bridge circuit 11, is the AC output terminal of affiliated bridge arm 10, second end is affiliated bridge arm 10
Neutral terminal.
Optionally, half-bridge circuit 11 includes concatenated first power cell and the second power cell；Common emitter circuit 12 wraps
Include concatenated third power cell and the 4th power cell.Wherein, the first end of the first power cell is the honest of affiliated bridge arm
Terminal is flowed, second end is the AC output terminal of affiliated bridge arm；The first end of second power cell is electrically connected with AC output terminal
It connects, second end is negative DC terminal of affiliated bridge arm；The first end of third power cell is electrically connected with AC output terminal, and second
End is electrically connected with the first end of the 4th power cell；The second end of 4th power cell is the neutral terminal of affiliated bridge arm.
Optionally, the first power cell, the second power cell, third power cell and the 4th power cell are IGBT.
First end, the second end of first power cell are respectively collector, the emitter of the first IGBT；The first of second power cell
End, second end are respectively collector, the emitter of the 2nd IGBT；First end, the second end of third power cell are respectively third
Collector, the emitter of IGBT；First end, the second end of 4th power cell are respectively emitter, the collector of the 4th IGBT.
Optionally, busbar support capacitance module includes the first capacitance group and the second capacitance group；First capacitance group passes through first
Circuit 21, third connection circuit 23 are connected, is electrically connected respectively with the positive direct current terminal of bridge arm 10, neutral terminal；Second capacitance group
Circuit 24 is connected by the second connection circuit the 22, the 4th, is electrically connected respectively with the negative DC terminal of bridge arm 10, neutral terminal.
Optionally, the first capacitance group includes at least one first capacitance, and the second capacitance group includes at least one second capacitance；
When the first capacitance is more than two, each first capacitance is in parallel；When the second capacitance be two on more than when, each second capacitance is simultaneously
Connection.
Further, the first end of the first capacitance C1 is electrically connected by the first connection circuit 21 and the positive direct current terminal of bridge arm 10
It connects, second end connects circuit 23 by third and is electrically connected with the neutral terminal of bridge arm 10；The first end of second capacitance C2 passes through
Four connection circuits 24 are electrically connected with the neutral terminal of bridge arm 10, the negative direct current that second end passes through the second connection circuit 22 and bridge arm 10
Terminal is electrically connected.
Specifically, the first capacitance C1 and the second capacitance C2 include positive terminal and negative pole end；The positive terminal of first capacitance C1
It is electrically connected with the positive direct current terminal of each bridge arm 10 by the first connection circuit 21, negative pole end is by third connection circuit 23 and respectively
The neutral terminal of a bridge arm 10 is electrically connected；The neutral end that the positive terminal of second capacitance C2 passes through the 4th connection circuit 24 and bridge arm 10
Son electrical connection, negative pole end are electrically connected by the second connection circuit 22 with negative DC terminal of bridge arm 10.
The concrete principle of power circuit provided by the embodiments of the present application will be described in detail in further part, and details are not described herein.
Therefore, the embodiment of the present application one at least has the following effects that：
By using connection circuit by the electrical connection corresponding with busbar support capacitance module of three level bridge arm modules, and make three electricity
The angle that the electric current input path of flat bridge arm module and current out path are formed is less than preset angle threshold so that electric current is defeated
Enter that path and circuit output path are almost mutually parallel and current direction is opposite so that the magnetic field of two-way electric current largely mutually offsets
Disappear, and then the parasitic inductance on electric current carrying pathway is made to be reduced to a lower numerical value, substantially reduces three level bridge arm moulds
Generated back-emf, the power electric component greatly reduced in bridge arm were switching when switching between different bridge arms in block
Voltage stress in journey can promote the stability of the power electric component in bridge arm, to promote entire three level bridge arm
The stability of module.
Embodiment two
Based on identical inventive concept, the embodiment of the present application two provides a kind of power module, which includes：It is folded
Layer busbar, and such as any one power circuit in the embodiment of the present application one.
In the embodiment of the present application, three level bridge arm modules in power circuit and busbar support capacitance module are set to folded
On layer busbar, three level bridge arm modules are set to first area；Busbar support capacitance module in power circuit is set to first
The second area of region face.
In the embodiment of the present application, stack bus bar includes：It is provided with the first busbar of the first connection circuit, is provided with second
It connects the second busbar of circuit and is provided with the third busbar of third connection circuit and the 4th connection circuit.
The embodiment of the present application two additionally provides alternatively possible realization method, is specifically described as follows：
Optionally, the quantity of three level bridge arm modules is at least one, and each three level bridge arm module may be contained within first
Region；Each three level bridge arm module includes in parallel even number bridge arm 10, the first bridge arm in even number bridge arm 10 and the
Two bridge arms are centrosymmetric relative to specified symmetric points.Wherein, by taking Fig. 5, Fig. 7 and Fig. 9 as an example, symmetric points such as Fig. 5, figure are specified
In 7 and Fig. 9 shown in black dot.
When the quantity of three level bridge arm modules is one, above-mentioned power module is the power module with single-phase bridge arm
(abbreviation single-phase power module).As shown in Figures 4 to 6, it includes a bridge that wherein circuit shown in Fig. 4, which is three level bridge arm modules,
The situation of arm 10, three level bridge arm modules include the situation of the first bridge arm and second two bridge arms 10 of bridge arm in circuit shown in Fig. 5,
Two bridge arms 10 are centrosymmetric relative to specified symmetric points.
Fig. 6 shows the circuit diagram of single-phase power module shown in Fig. 5, and is shown using dotted line with the arrow in Fig. 6
Current path when the second capacitance C2 electric discharges, the direction of arrow meaning on the dotted line are electricity when the second capacitance C2 discharges
Flow direction.
When three level bridge arm modules are there are when even number bridge arm 10, the first bridge arm is in parallel with the second bridge arm, with shown in fig. 5
For two bridge arms, specifically, the half-bridge circuit 11 in the first bridge arm (bridge arm 10 of Fig. 5 top halfs) and second bridge arm (Fig. 5
The bridge arm 10 of top half) in half-bridge circuit it is in parallel, the cascode in common emitter circuit 12 and the second bridge arm in the first bridge arm
Polar circuit 12 is in parallel.
When the quantity of three level bridge arm modules is two, above-mentioned power module is the power module with two-phase bridge arm
(abbreviation two-phase power module), as shown in Figure 7.Fig. 8 shows the circuit diagram of two-phase power shown in Fig. 7.When three level bridges
When the quantity of arm module is three, above-mentioned power module is the power module (abbreviation three phase power module) with three-phase bridge arm,
As shown in Figure 9.
Each three level bridge arm module includes two bridges of the first bridge arm and the second bridge arm in Fig. 7 and circuit shown in Fig. 9
Arm 10, two bridge arms 10 are centrosymmetric relative to specified symmetric points.
Since the first bridge arm and the second bridge arm are centrosymmetric, make electricity of two bridge arms 10 apart from busbar support capacitance module
Steaming transfer path is of substantially equal, and impedance is conducive to the stream effect of enhancing parallel connection close to unanimously.
Optionally, power module provided by the embodiments of the present application further includes ac bus, and the AC output terminal of bridge arm is set
Position corresponding with ac bus is placed in first area, and AC output terminal is electrically connected with ac bus.
Further, ac bus can be exchange confluence busbar 14.Specifically, N phases power module may include and N number of phase
The corresponding N number of exchange confluence busbar 14 in position, the AC output terminal exchange confluence corresponding with the phase of each phase
Busbar 14 is electrically connected, and the output current of the AC output terminal of each phase can pass through corresponding one exchange confluence busbar 14
Confluence is drawn.Wherein, N is the integer more than zero.Optionally, exchange confluence busbar 14 and stack bus bar 13 are misaligned.
For example, when power module is Fig. 4 or shown in fig. 5 single-phase power modules, which includes one
Each AC output terminal of exchange confluence busbar 14, the single-phase power module is electrically connected with exchange confluence busbar 14；When
When power module is two-phase power module shown in Fig. 7, A phases, B phases AC output terminal exchange remittance with A phases, B phases respectively
Busbar 14 is flowed to be electrically connected；When power module is three phase power module shown in Fig. 9, the AC output terminal of A phase, B phase, C phase
It is electrically connected respectively with the exchange of A phase, B phase, C phase confluence busbar 14.
Optionally, power module provided by the embodiments of the present application can be used the IGBT module that 62mm is encapsulated and be built.
Optionally, the first capacitance group in busbar support capacitance module, the second capacitance group, are respectively arranged in second area
And position corresponding with the second bridge arm in the corresponding position of the first bridge arm, second area；For example, two of the first capacitance can be made to hold
The line of son is directed toward the first bridge arm direction, and the line of two terminals of the second capacitance is made to be directed toward the second bridge arm.
Optionally, the first busbar, the second busbar, third busbar are respectively positive busbar, negative busbar, zero busbar；Zero busbar is set
It sets between positive busbar and negative busbar.
The the first capacitance C1 and the second capacitance that each bridge arm 10 passes through three layer laminate busbars 13 and bus capacitor supporting module
C2 is electrically connected, and the magnetic field cancellation generated using current path opposite in adjacent layer in stack bus bar 13 can further decrease electricity
The stray inductance generated in stream transmission procedure.
Below by taking Fig. 4 and the power module shown in fig. 5 with single-phase bridge arm as an example, to provided by the embodiments of the present application
The structure and principle of power module are further described：
In the embodiment of the present application, the positive direct current terminal of each bridge arm 10, negative DC terminal, neutral terminal are female with direct current respectively
The positive current end of line, negative current end, neutral point electrical connection.DC bus can be DC master row, and further, DC master row can
To be stack bus bar.
Positive direct current terminal, negative DC terminal of each bridge arm 10, connect circuit 21 by first in positive busbar respectively, bear
The second connection circuit 22 on busbar is electrically connected with busbar support capacitance module；The neutral terminal of each bridge arm 10 passes through zero respectively
Third connection circuit the 23, the 4th on busbar connects circuit 24 and is electrically connected with busbar support capacitance module.Positive busbar, negative busbar,
Zero busbar is respectively the positive current end, negative current end, neutral end of DC bus.
Specifically, the positive direct current terminal of bridge arm 10 is electrically connected with the first capacitance C1 in busbar support capacitance module, is born straight
Stream terminal is electrically connected with the second capacitance C2 in busbar support capacitance module, and the first capacitance C1 and the second capacitance C2 are and neutral end
Son electrical connection.
Each bridge arm 10 is electrically connected by three layer laminate busbars 13 with bus capacitor supporting module, due to 13 phase of stack bus bar
Adjacent bed is parallel, and the electric current transmission direction of circuit is connected in adjacent layer on the contrary, the magnetic field that therefore current path of different layers generates
It can cancel out each other, to reduce the stray inductance generated in electric current transmission process.
When the first capacitance C1 electric discharges, electric current is flowed into bridge arm 10, along third along the first connection circuit 21 from DC+ terminals
Circuit 23 is connected, the first capacitance C1 is flowed out to from NP terminals；When the first capacitance C1 chargings, current path direction is on the contrary, in Fig. 5
In be not shown.
When the second capacitance C2 electric discharges, electric current is being flowed into bridge arm 10 along the 4th connection circuit 24 from NP terminals, along second
Connection circuit 22 flows out to the current path of the second capacitance C2 from DC- terminals；When the second capacitance C2 chargings, current path direction
On the contrary；The current path for being related to the second capacitance C2 is not shown in FIG. 5.
Optionally, above-mentioned first connection circuit 21, second connects circuit 22, third connection circuit 23 and the 4th connects circuit
24, respectively less than preset length threshold；The length threshold can be set according to actual demand.
The embodiment of the present application realizes the transmission path and toggle path for reducing electric current by reducing each length for connecting circuit
Purpose, the stray inductance generated when to reduce current switching.
Optionally, the first end of half-bridge circuit is electrically connected as the positive direct current terminal of affiliated bridge arm with positive busbar in bridge arm,
Second end is electrically connected as negative DC terminal of affiliated bridge arm with negative busbar；
The first end of common emitter circuit is defeated as the AC output terminal of affiliated bridge arm and exchanging for half-bridge circuit in bridge arm
Outlet is electrically connected, and second end is electrically connected as the neutral terminal of affiliated bridge arm with zero busbar.
Optionally, the first end of the first power cell in half-bridge circuit is electrically connected with positive busbar, second end with exchange it is defeated
Outlet is electrically connected；The first end of the second power cell is electrically connected with ac output end in half-bridge circuit, second end and negative busbar electricity
Connection；The first end of third power cell is electrically connected with ac output end in common emitter circuit, second end and the 4th power cell
First end electrical connection；The second end of the 4th power cell is to be electrically connected with zero busbar in common emitter circuit.
Following introduce is made to the concrete principle of power circuit provided by the embodiments of the present application and power module below：
When the first capacitance C1 electric discharges, electric current is flowed into bridge arm 10, along third along the first connection circuit 21 from DC+ terminals
Connect circuit 23, the first capacitance C1 flowed out to from NP terminals, preceding two dotted lines in current path such as Fig. 4 from top to bottom and
Shown in dotted line in Fig. 5, shown in the direction of the arrow meaning in current direction such as Fig. 4 and Fig. 5 on corresponding dotted line；When the first electricity
When holding C1 chargings, current path direction is on the contrary, in preceding two dotted lines and Fig. 5 in its current path such as Fig. 4 from top to bottom
Shown in dotted line, current direction is not shown in figures 4 and 5, but does not influence those skilled in the art to technical scheme
Understanding.
When the second capacitance C2 electric discharges, electric current is being flowed into bridge arm 10 along the 4th connection circuit 24 from NP terminals, along second
Connection circuit 22 flows out to the second capacitance C2 from DC- terminals, rear two dotted lines in current path such as Fig. 4 from top to bottom and
In Fig. 6 shown in dotted line with the arrow, shown in the direction of the arrow meaning in current direction such as Fig. 4 and Fig. 6 on corresponding dotted line；When
When the second capacitance C2 charging, current path direction is on the contrary, rear two dotted lines and figure in its current path such as Fig. 4 from top to bottom
In 6 shown in dotted line with the arrow, current direction is not shown in Fig. 4 and Fig. 6, but does not influence those skilled in the art to this Shen
Please technical solution understanding.
The current path for being related to the second capacitance C2 is not shown in FIG. 5, and with reference to Fig. 4 and Fig. 6, those skilled in the art can
To understand that therefore not to repeat here there are corresponding current path and current direction in Fig. 5.
Optionally, the first connection circuit 21 connects the sum of the length of circuit 23 with third, is less than preset first length threshold
Value；Second connection circuit 22 and the 4th connects the sum of the length of circuit 24, is less than preset second length threshold.First length threshold
Value and the second length threshold can be set according to actual demand.
By the way that the first length threshold is arranged, it can reduce when the first capacitance C1 charge or discharge, by the first connection circuit 21
The electric current that the formation of circuit 23 is connected with third outputs and inputs path；By the way that the second length threshold is arranged, can reduce when the second electricity
When holding C2 charge or discharge, the electric current that circuit 24 is formed is connected by the second connection circuit 22 and the 4th and outputs and inputs path.By
This can reduce entire electric current carrying pathway and toggle path, the stray inductance generated when to reduce entire current switching.
Fig. 7 is similar to the single-phase power module in Fig. 5, Fig. 6 to the principle of two-phase shown in Fig. 9 or three phase power module,
Below by taking Fig. 7 and structure shown in Fig. 8 and circuit theory as an example, the principle of two-phase power module is slightly illustrated：In Fig. 7 and figure
In two-phase power module shown in 8, when the first capacitance C1 electric discharges, electric current connects circuit 21 along the first of A phases, from DC+ terminals
Be flowed into bridge arm 10, the third along B phases connects circuit 23, and the first capacitance C1 is flowed out to from NP terminals, current path such as Fig. 7 and
In Fig. 8 shown in dotted line, shown in the direction of the arrow meaning in current direction such as Fig. 7 and Fig. 8 on dotted line；When the first capacitance C1 fills
When electric, the current direction in current path on the contrary, in its current path such as Fig. 7 and Fig. 8 shown in dotted line, do not scheming by current direction
It is shown in 7 and Fig. 8, but does not influence understanding of the those skilled in the art to technical scheme.
As the above analysis, when the first capacitance C1 charge or discharge, the first connection electricity of three level bridge arm module of A phases
What road 21 connected that circuit 23 forms same current loop with the third of three level bridge arm module of B phases outputs and inputs path, if
The the first connection circuit 21 for setting three level bridge arm module of A phases connects the length of circuit 23 with the third of three level bridge arm module of B phases
The sum of be less than preset third length threshold, can equally reduce entire electric current carrying pathway and toggle path, it is entire to reduce
The stray inductance generated when current switching.
When the second capacitance C2 charge or discharge, principle is similar with the principle of the first capacitance C1, and therefore not to repeat here.
The technical solution of the embodiment of the present application two, at least has the advantages that：
1) by using connection circuit by the electrical connection corresponding with busbar support capacitance module of three level bridge arm modules, and make three
The angle that the electric current input path of level bridge arm module and current out path are formed is less than preset angle threshold, and then makes electricity
Parasitic inductance on steaming transfer path is reduced to a lower numerical value；
2) by the length of each connection circuit of reduction, the purpose of the transmission path and toggle path that reduce electric current is can reach,
The stray inductance generated when to reduce current switching；
3) by reducing the stray inductance in electric current carrying pathway, the judgement voltage that can be effectively reduced power cell is answered
Power；
4) at least two bridge arms are in parallel in three level bridge arm modules, and advantageous realize flows effect；Due in three level bridge arms
The first bridge arm and the second bridge arm be centrosymmetric, make two parts bridge arm apart from the electric current carrying pathway of busbar support capacitance module
Of substantially equal, impedance can enhance stream effect in parallel close to unanimously.
Embodiment three
Based on identical inventive concept, the embodiment of the present application three provides a kind of current transformer, which includes the application
Any one power module that embodiment two provides.
It will be understood by those skilled in the art that current transformer provided by the embodiments of the present application may also include rectification circuit, filtering
Any one or more circuit structure such as circuit, control circuit, therefore not to repeat here.
Based on any one power module that the embodiment of the present application two provides, the embodiment of the present application three at least has and has as follows
Beneficial effect：
1) by using connection circuit by the electrical connection corresponding with busbar support capacitance module of three level bridge arm modules, and make three
The angle that the electric current input path of level bridge arm module and current out path are formed is less than preset angle threshold so that electric current
It inputs path and circuit output path is almost mutually parallel and current direction is opposite so that the magnetic field of two-way electric current is largely mutual
It offsets, and then the stray inductance on electric current carrying pathway is made to be reduced to a lower numerical value, substantially reduce three level bridge arms
Generated back-emf, the power electric component greatly reduced in bridge arm are switching when switching between different bridge arms in module
Voltage stress in the process can promote the stability of the power electric component in bridge arm, can be promoted when bridge arm switches
Stability, to promote the stability of entire three level bridge arm module.
2) in three level bridge arm modules in the application per phase, including even number bridge arm in parallel, even number bridge in parallel
Arm is conducive to averraged output current compared to existing single bridge arm, and effect is flowed in promotion, reduces each bridge arm transmission electricity
The burden of stream promotes the stability and reliability of each bridge arm, extends the service life of bridge arm.
3) in the application, the first bridge arm and the second bridge arm in three level bridge arm modules in even number bridge arm are arranged in mirror image
Row, keep two parts bridge arm 10 of mirror alignment of substantially equal apart from the electric current carrying pathway of busbar support capacitance module, impedance connects
It is close consistent, stream effect in parallel can be enhanced.
4) by the length of each connection circuit of reduction, the purpose of the transmission path and toggle path that reduce electric current is can reach,
The stray inductance generated when to reduce current switching.
The above is only some embodiments of the application, it is noted that for the ordinary skill people of the art
For member, under the premise of not departing from the application principle, several improvements and modifications can also be made, these improvements and modifications are also answered
It is considered as the protection domain of the application.
Claims (14)
1. a kind of power circuit, which is characterized in that including：Three level bridge arm modules and busbar support capacitance module, three electricity
Flat bridge arm module includes at least one bridge arm；
The positive direct current terminal of the bridge arm is electrically connected by the first connection circuit with the busbar support capacitance module；The bridge arm
Negative DC terminal by second connection circuit be electrically connected with the busbar support capacitance module；The neutral terminal of the bridge arm point
Circuit is not connected by third, the 4th connection circuit is electrically connected with the busbar support capacitance module；
The angle that the first connection circuit connect circuit with the third is less than preset angle threshold, and/or, described second
The angle that connection circuit connect circuit with the described 4th is less than preset angle threshold.
2. power circuit according to claim 1, which is characterized in that the power circuit is T-NPC three-level topology electricity
Road.
3. power circuit according to claim 2, which is characterized in that the bridge arm includes the half-bridge circuit of electrical connection and is total to
Emitter base diode circuit；
The first end of the half-bridge circuit is the positive direct current terminal of affiliated bridge arm, and second end is negative DC terminal of affiliated bridge arm；
The first end of the common emitter circuit is electrically connected with the ac output end of half-bridge circuit, is the ac output end of affiliated bridge arm
Son, second end are the neutral terminal of affiliated bridge arm.
4. power circuit according to claim 1, which is characterized in that the busbar support capacitance module includes the first capacitance
Group and the second capacitance group；
First capacitance group connects circuit by described first, the third connects circuit, honest with the bridge arm respectively
Flow terminal, neutral terminal electrical connection；
Second capacitance group connects circuit, the 4th connection circuit by described second, negative straight with the bridge arm respectively
Flow terminal, neutral terminal electrical connection.
5. power circuit according to claim 4, which is characterized in that first capacitance group includes at least one first electricity
Hold, second capacitance group includes at least one second capacitance；
When first capacitance is more than two, each first capacitance is in parallel；When second capacitance be two on more than when, respectively
A second capacitance is in parallel；
The first end of first capacitance connects circuit by described first and is electrically connected with the positive direct current terminal of the bridge arm, and second
End connects circuit by the third and is electrically connected with the neutral terminal of the bridge arm；
The first end of second capacitance connects circuit by the described 4th and is electrically connected with the neutral terminal of the bridge arm, second end
Circuit is connected by described second to be electrically connected with negative DC terminal of the bridge arm.
6. a kind of power module, which is characterized in that including：Stack bus bar, and it is such as according to any one of claims 1 to 5
Power circuit；
The three level bridge arm module and the busbar support capacitance module are set on the stack bus bar；
The three level bridge arm module is set to first area；
The busbar support capacitance module is set to the second area of the first area face；
The stack bus bar includes：The second mother for being provided with the first busbar of the first connection circuit, being provided with the second connection circuit
Row and the third busbar for being provided with third connection circuit and the 4th connection circuit.
7. power module according to claim 6, which is characterized in that the first connection circuit connects electricity with the third
The sum of the length on road is less than preset first length threshold；The length of the second connection circuit and the 4th connection circuit
The sum of, it is less than preset second length threshold.
8. power module according to claim 7, which is characterized in that the quantity of the three level bridge arm module is at least one
A, each three level bridge arm module may be contained within the first area；
Each three level bridge arm module includes bridge arm described in even number in parallel, the first bridge in bridge arm described in even number
Arm and the second bridge arm are centrosymmetric relative to specified symmetric points.
9. power module according to claim 8, which is characterized in that further include ac bus；
The AC output terminal of the bridge arm is set to position corresponding with the ac bus, the friendship in the first area
Stream leading-out terminal is electrically connected with the ac bus.
10. power module according to claim 8, which is characterized in that the first electricity in the busbar support capacitance module
Appearance group, the second capacitance group, be respectively arranged in the second area in position corresponding with the first bridge arm, the second area with
The corresponding position of second bridge arm.
11. power module according to claim 8, which is characterized in that
First busbar, the second busbar, third busbar are respectively positive busbar, negative busbar, zero busbar；
Zero busbar is arranged between the positive busbar and negative busbar.
12. power module according to claim 11, which is characterized in that the first end conduct of half-bridge circuit in the bridge arm
The positive direct current terminal of affiliated bridge arm is electrically connected with positive busbar, negative DC terminal and the negative busbar of the second end as affiliated bridge arm
Electrical connection；
Friendship of the first end of common emitter circuit as the AC output terminal and the half-bridge circuit of affiliated bridge arm in the bridge arm
Output end electrical connection is flowed, second end is electrically connected as the neutral terminal of affiliated bridge arm with zero busbar.
13. power module according to claim 12, which is characterized in that the of the first power cell in the half-bridge circuit
One end is electrically connected with the positive busbar, and second end is electrically connected with the ac output end；
The first end of the second power cell is electrically connected with the ac output end in the half-bridge circuit, second end and negative busbar electricity
Connection；
The first end of third power cell is electrically connected with ac output end in the common emitter circuit, second end and the 4th power list
The first end electrical connection of member；
The second end of the 4th power cell is to be electrically connected with zero busbar in the common emitter circuit.
14. a kind of current transformer, which is characterized in that include the power module as described in any one of claim 6-13.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810696727.6A CN108768195B (en) | 2018-06-29 | 2018-06-29 | Power circuit, power module and converter |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810696727.6A CN108768195B (en) | 2018-06-29 | 2018-06-29 | Power circuit, power module and converter |
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| CN108768195A true CN108768195A (en) | 2018-11-06 |
| CN108768195B CN108768195B (en) | 2021-04-02 |
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| CN114079389A (en) * | 2020-08-12 | 2022-02-22 | 中车株洲电力机车研究所有限公司 | Converter module and main structure thereof |
| CN114088986A (en) * | 2020-08-05 | 2022-02-25 | 华中科技大学 | Dynamic test board for needle-shaped terminal half-bridge type power module |
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| CN204168127U (en) * | 2014-06-30 | 2015-02-18 | 阳光电源股份有限公司 | A kind of power modules |
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| CN102882385A (en) * | 2012-10-22 | 2013-01-16 | 台达电子工业股份有限公司 | Laminated busbar structure for three-level power converter and power converter |
| CN103107713A (en) * | 2013-01-29 | 2013-05-15 | 上海电气集团股份有限公司 | Laminated busbar used for diode clamp type three-level converter |
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| CN114088986B (en) * | 2020-08-05 | 2024-05-24 | 华中科技大学 | Dynamic test board for needle-shaped terminal half-bridge type power module |
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| CN108768195B (en) | 2021-04-02 |
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