CN210111864U - Four-level AC-AC converter and any integer level AC-AC converter obtained by expanding four-level AC-AC converter - Google Patents
Four-level AC-AC converter and any integer level AC-AC converter obtained by expanding four-level AC-AC converter Download PDFInfo
- Publication number
- CN210111864U CN210111864U CN201920879729.9U CN201920879729U CN210111864U CN 210111864 U CN210111864 U CN 210111864U CN 201920879729 U CN201920879729 U CN 201920879729U CN 210111864 U CN210111864 U CN 210111864U
- Authority
- CN
- China
- Prior art keywords
- switching tube
- quadrant switching
- quadrant
- node
- converter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Abstract
The utility model discloses a four-level AC-AC converter and any integer level AC-AC converter obtained by the expansion of the four-level AC-AC converter, which comprises an AC input power supply, a three-winding transformer, a four-level conversion unit, an output filter and an AC load; the four-level conversion unit comprises first to sixth four-quadrant switching tubes, a first flying capacitor and a second flying capacitor; the first flying capacitor is bridged between a second node between the second four-quadrant switching tube and the third four-quadrant switching tube and a fourth node between the fourth four-quadrant switching tube and the fifth four-quadrant switching tube, and the second flying capacitor is bridged between a first node between the first four-quadrant switching tube and the second four-quadrant switching tube and a fifth node between the fifth four-quadrant switching tube and the sixth four-quadrant switching tube; a first secondary winding of the three-winding transformer is connected with the first flying capacitor in parallel, and a second secondary winding of the three-winding transformer is connected with the second flying capacitor in parallel. The utility model discloses can guarantee that output voltage can adjust at full duty cycle within range, can avoid the control problem of many level converter flying electric capacity again, compare with two levels, can also make the voltage stress of switch tube reduce to original 1/3 times.
Description
Technical Field
The utility model relates to a power electronic transformation technique, concretely relates to from following four level AC-AC converters of flying capacitor and extending arbitrary integer level AC-AC converter that obtains by it based on three winding transformers.
Background
AC-AC conversion technology is a conversion technology that uses power electronics to convert AC power of a certain frequency and amplitude into AC power of another frequency and amplitude. After a rapid development for more than half a century, the device is widely applied to various fields requiring electric energy conversion. In the low-voltage and low-power electricity utilization occasions, the AC-AC conversion technology has become mature in many aspects; in the transmission and distribution and industrial occasions with high voltage and high power, the application of the AC-AC conversion technology is becoming the key point and the focus of the current research, and is limited by the voltage withstanding value of power electronic devices, and the multi-level technology becomes an effective way for solving the problem.
Disclosure of Invention
The utility model discloses the purpose is: the four-level AC-AC converter and any integer level AC-AC converter obtained by expanding the four-level AC-AC converter can ensure that the output voltage can be adjusted in a full duty ratio range, can avoid the control problem of flying capacitors in a multi-level converter, and can reduce the voltage stress of a switching tube to 1/3 times of the original voltage stress compared with two levels.
The technical scheme of the utility model is that: a four-level AC-AC converter comprises an AC input power supply, a three-winding transformer, a four-level conversion unit, an output filter and an AC load, wherein the AC input power supply, the four-level conversion unit, the output filter and the AC load are sequentially connected;
the four-level conversion unit comprises a first four-quadrant switching tube, a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube, a fifth four-quadrant switching tube, a sixth four-quadrant switching tube, a first flying capacitor and a second flying capacitor;
a first node is formed between the first four-quadrant switching tube and the second four-quadrant switching tube, a second node is formed between the second four-quadrant switching tube and the third four-quadrant switching tube, a third node is formed between the third four-quadrant switching tube and the fourth four-quadrant switching tube, a fourth node is formed between the fourth four-quadrant switching tube and the fifth four-quadrant switching tube, and a fifth node is formed between the fifth four-quadrant switching tube and the sixth four-quadrant switching tube;
the first flying capacitor is connected across the second node and the fourth node, and the second flying capacitor is connected across the first node and the fifth node;
two ends of a primary winding of the three-winding transformer are respectively connected to a first output end point and a second output end point of an alternating current input power supply of the converter, a first secondary winding of the three-winding transformer is connected with the first flying capacitor in parallel, and a second secondary winding of the three-winding transformer is connected with the second flying capacitor in parallel;
one end of the first four-quadrant switching tube is connected to a first output end point of the converter alternating-current input power supply, the other end of the first four-quadrant switching tube is connected to one end of a sixth four-quadrant switching tube through a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube and a fifth four-quadrant switching tube in sequence, and the other end of the sixth four-quadrant switching tube is connected to a second output end point of the converter alternating-current input power supply;
the first input end point of the output filter is connected to the third node, and the second input end point of the output filter is connected to the second output end point of the converter alternating current input power supply.
In the above technical solution, the first four-quadrant switching tube includes a first power switching tube and a second power switching tube connected in series in an opposite direction;
the second four-quadrant switching tube comprises a third power switching tube and a fourth power switching tube which are connected in series in an opposite direction;
the third four-quadrant switching tube comprises a fifth power switching tube and a sixth power switching tube which are connected in series in an opposite direction;
the fourth four-quadrant switching tube comprises a seventh power switching tube and an eighth power switching tube which are connected in series in an opposite direction;
the fifth four-quadrant switching tube comprises a ninth power switching tube and a tenth power switching tube which are connected in series in an opposite direction;
the sixth four-quadrant switching tube comprises an eleventh power switching tube and a twelfth power switching tube which are connected in series in an opposite direction.
In the above technical solution, the first power switch tube, the second power switch tube, the third power switch tube, the fourth power switch tube, the fifth power switch tube, the sixth power switch tube, the seventh power switch tube, the eighth power switch tube, the ninth power switch tube, the tenth power switch tube, the eleventh power switch tube and the twelfth power switch tube are all IGBT switch tubes or MOSFET switch tubes.
In the above technical solution, the output filter includes an output inductor and an output filter capacitor.
In the technical scheme, the turn ratio of a primary winding and a first secondary winding of the three-winding transformer is 3: 1;
the turn ratio of a primary winding to a second secondary winding of the three-winding transformer is 3: 2.
In the above technical solution, the dotted terminals of the primary side, the second secondary side, and the first secondary side of the three-winding transformer are respectively connected to the first output end point, the first node, and the second node of the ac input power supply of the converter.
In the above, the dotted terminals of the primary sides of the three-winding transformers are correspondingly connected to the first output end point of the ac input power supply of the converter, the dotted terminals of the second secondary sides of the three-winding transformers are correspondingly connected to the first node, and the dotted terminals of the first secondary sides of the three-winding transformers are correspondingly connected to the second node.
The utility model discloses an use two independent secondary limits of three-winding transformer to supply power for two flying capacitors for the voltage of two flying capacitors is automatic to be followed 1/3, 2/3 times input voltage and realizes flying capacitor's clamping effect.
A four-level AC-AC converter comprises an AC input power supply, an input inductor, a four-level conversion unit, a three-winding transformer, an output filter capacitor and an AC load, wherein the AC input power supply, the input inductor, the four-level conversion unit, the output filter capacitor and the AC load are sequentially connected;
the four-level conversion unit comprises a first four-quadrant switching tube, a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube, a fifth four-quadrant switching tube, a sixth four-quadrant switching tube, a first flying capacitor and a second flying capacitor;
a first node is formed between the first four-quadrant switching tube and the second four-quadrant switching tube, a second node is formed between the second four-quadrant switching tube and the third four-quadrant switching tube, a third node is formed between the third four-quadrant switching tube and the fourth four-quadrant switching tube, a fourth node is formed between the fourth four-quadrant switching tube and the fifth four-quadrant switching tube, and a fifth node is formed between the fifth four-quadrant switching tube and the sixth four-quadrant switching tube;
the first flying capacitor is connected across the second node and the fourth node, and the second flying capacitor is connected across the first node and the fifth node;
two ends of a primary winding of the three-winding transformer are respectively connected to a first end point and a second end point of the output filter capacitor, a first secondary winding of the three-winding transformer is connected with the first flying capacitor in parallel, and a second secondary winding of the three-winding transformer is connected with the second flying capacitor in parallel;
one end of the first four-quadrant switching tube is connected to a first end point of the output filter capacitor, the other end of the first four-quadrant switching tube is connected to one end of a sixth four-quadrant switching tube through a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube and a fifth four-quadrant switching tube in sequence, and the other end of the sixth four-quadrant switching tube is connected to a second output end point of the converter alternating-current input power supply and a second end point of the output filter capacitor respectively;
the third node is connected to the first output end point of the alternating current input power supply of the converter through the input inductor.
A four-level AC-AC converter comprises an AC input power supply, a four-level conversion unit, an energy storage inductor, a three-winding transformer, an output filter capacitor and an AC load;
the four-level conversion unit comprises a first four-quadrant switching tube, a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube, a fifth four-quadrant switching tube, a sixth four-quadrant switching tube, a first flying capacitor and a second flying capacitor;
a first node is formed between the first four-quadrant switching tube and the second four-quadrant switching tube, a second node is formed between the second four-quadrant switching tube and the third four-quadrant switching tube, a third node is formed between the third four-quadrant switching tube and the fourth four-quadrant switching tube, a fourth node is formed between the fourth four-quadrant switching tube and the fifth four-quadrant switching tube, and a fifth node is formed between the fifth four-quadrant switching tube and the sixth four-quadrant switching tube;
the first flying capacitor is connected across the second node and the fourth node, and the second flying capacitor is connected across the first node and the fifth node;
two ends of a primary winding of the three-winding transformer are respectively connected to a first output end point of an alternating current input power supply of the converter and a first end point of an output filter capacitor, a first secondary winding of the three-winding transformer is connected with a first flying capacitor in parallel, and a second secondary winding of the three-winding transformer is connected with a second flying capacitor in parallel;
one end of the first four-quadrant switching tube is connected to a first output end point of an alternating current input power supply of the converter, the other end of the first four-quadrant switching tube is connected to one end of a sixth four-quadrant switching tube through a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube and a fifth four-quadrant switching tube in sequence, and the other end of the sixth four-quadrant switching tube is connected to a first end point of an output filter capacitor;
and the third node is respectively connected to a second output endpoint of the alternating current input power supply of the converter and a second endpoint of the output filter capacitor through the energy storage inductor.
An arbitrary integer level AC-AC converter is obtained based on four-level AC-AC converter expansion.
The utility model has the advantages that:
1. the utility model discloses a two independent secondary sides of three-winding transformer are two flying capacitors power supply, not only can make the voltage of two flying capacitors automatically follow 1/3, 2/3 times input voltage and realize the clamping effect of flying capacitor, can also avoid the control problem of flying capacitor voltage in the multilevel AC-AC converter, the control strategy of multilevel AC-AC converter has greatly been simplified, and the capacity of this three-winding transformer is very little, theoretically only need satisfy the reactive load of two flying capacitors can;
2. the four-level AC-AC converter of the utility model can reduce the voltage stress of the switch tube, and the voltage stress is only 1/3 corresponding to the two-level AC-AC converter;
3. the four-level AC-AC converter of the utility model can obtain high-frequency output voltage with frequency three times of the working frequency of the switching tube at G, E two points before the output filtering when in work, thus greatly reducing the size of the output filter;
4. based on the utility model discloses a topological structure of four levels can obtain the AC-AC converter of arbitrary integer level.
Drawings
The invention will be further described with reference to the following drawings and examples:
fig. 1 is a schematic circuit diagram according to a first embodiment of the present invention.
Fig. 2 is a timing diagram and a main waveform diagram of each switching tube when the duty ratio D of the first embodiment of the present invention is less than 1/3.
FIG. 3 is a timing diagram and a main waveform diagram of each switching tube when the duty ratio 1/3 is not less than D < 2/3 according to the first embodiment of the present invention.
Fig. 4 is a timing diagram and a main waveform diagram of each switching tube when the duty ratio 2/3 is not greater than D according to the embodiment of the present invention.
Fig. 5 is a schematic circuit diagram of a second embodiment of the present invention.
Fig. 6 is a schematic circuit diagram of a third embodiment of the present invention.
Detailed Description
The first embodiment is as follows:
referring to fig. 1, a four-level AC-AC converter, particularly in Buck mode, includes an AC input power uiThree-winding transformer TrFour-level conversion unit, output filter and alternating current load RoSaid AC input power uiFour-level conversion unit, output filter and alternating current load RoAre connected in sequence;
the four-level conversion unit comprises a first four-quadrant switching tube S5And the second four-quadrant switching tube S3And the third four-quadrant switching tube S1And the fourth four-quadrant switching tube S2And the fifth and fourth quadrant switch tube S4And the sixth four-quadrant switching tube S6A first flying capacitor Cy1And a second flying capacitor Cy2；
The first four-quadrant switching tube S5And a second four-quadrant switching tube S3A first node A is formed between the first and second four-quadrant switching tubes S3And a third four-quadrant switching tube S1A second node B is formed between the first and second four-quadrant switching tubes S1And a fourth four-quadrant switching tube S2A third node G is formed between the four-quadrant switching tube S2And a fifth four-quadrant switching tube S4Form a fourth node C therebetween, and the fifth four-quadrant switching tube S4And a sixth four-quadrant switching tube S6Form a fifth node D therebetween;
the first flying capacitor Cy1Connected across a second node B and a fourth node C, the second flying capacitor Cy2Is bridged between the first node A and the fifth node D;
the three-winding transformer TrPrimary winding N of1Are respectively connected to an AC input power u of the converteriA first output terminal I and a second output terminal E, the three-winding transformer TrFirst secondary winding N21And the first flying spanCapacitor Cy1In parallel, said three-winding transformer TrSecond secondary winding N22And a second flying capacitor Cy2Parallel connection;
the first four-quadrant switching tube S5Is connected to an AC input power u of the converteriThe first output end point I of the first four-quadrant switching tube S5The other end of the first four-quadrant switching tube passes through a second four-quadrant switching tube S in sequence3And the third four-quadrant switching tube S1And the fourth four-quadrant switching tube S2And a fifth four-quadrant switching tube S4Is connected to the sixth four-quadrant switching tube S6One end of the sixth four-quadrant switching tube S6Is connected to the converter AC input power u at the other endiA second output terminal E;
the first input end point of the output filter is connected to the third node G, and the second input end point of the output filter is connected to the AC input power u of the converteriAnd a second output terminal E.
In this embodiment, the first four-quadrant switching tube S5Comprising a first power switch S connected in series in the reverse direction5aAnd a second power switch tube S5b；
The second four-quadrant switching tube S3Comprising a third power switch S connected in series in the reverse direction3aAnd a fourth power switch tube S3b；
The third four-quadrant switching tube S1Comprising a fifth power switch tube S connected in reverse series1aAnd a sixth power switch tube S1b；
The fourth four-quadrant switching tube S2Comprising a seventh power switch tube S connected in reverse series2aAnd an eighth power switch tube S2b；
The fifth and fourth quadrant switching tube S4Comprising a ninth power switch tube S connected in reverse series4aAnd a tenth power switch tube S4b；
The sixth four-quadrant switching tube S6Comprising an eleventh power switch tube S connected in reverse series6aAnd a twelfth power switch tube S6b；
Specifically, the first power switch tube S5aIs connected to the second power switch tube S5bSaid first power switch tube S5aIs connected to the converter ac input power source uiThe first output terminal I of the first power switch tube S, the second power switch tube S5bIs connected to a first node a;
the third power switch tube S3aIs connected to the fourth power switch tube S3bSaid third power switch tube S3aIs connected to the first node a, said fourth power switch tube S3bIs connected to a second node B;
the fifth power switch tube S1aIs connected to the sixth power switch tube S1bThe fifth power switch tube S1aIs connected to the second node B, said sixth power switch S1bIs connected to a third node G;
the seventh power switch tube S2aIs connected to the eighth power switch tube S2bSaid seventh power switch tube S2aIs connected to a third node G, said eighth power switch S2bIs connected to a fourth node C;
the ninth power switch tube S4aIs connected to the tenth power switch tube S4bSaid ninth power switch tube S4aIs connected to a fourth node C, the tenth power switch tube S4bIs connected to the fifth node D;
the eleventh power switch tube S6aIs connected to the twelfth power switch tube S6bThe eleventh power switch tube S6aIs connected to a fifth node D, the twelfth power switch tube S6bIs connected to the converter ac input power source uiAnd a second output terminal E.
In this embodiment, the first power switch tube S5aA second power switch tube S5bThe third power switch tube S3aThe fourth power switch tube S3bThe fifth power switch tube S1aSixth power switch tube S1bSeventh power switch tube S2aThe eighth power switch tube S2bThe ninth power switch tube S4aThe tenth power switch tube S4bEleventh power switch tube S6aAnd a twelfth power switch tube S6bIs the IGBT switch tube, however the utility model discloses not only be limited to and use the IGBT switch tube, can also replace with MOSFET switch tube or other types's switch tube etc. to the MOSFET switch tube is the example, and at this moment, the source electrode of MOSFET switch tube corresponds the projecting pole of IGBT switch tube, and the drain electrode of MOSFET switch tube corresponds the collecting electrode of IGBT switch tube.
In this embodiment, the output filter includes an output inductor LfAnd an output filter capacitor Cf。
In this embodiment, the three-winding transformer TrPrimary winding N of1And a first secondary winding N21The turn ratio of (A) is 3: 1;
the three-winding transformer TrPrimary winding N of1And a second secondary winding N22The turns ratio of (a) to (b) is 3: 2.
In this embodiment, the three-winding transformer TrThe same-name ends of the primary side, the second secondary side and the first secondary side are respectively connected to an AC input power u of the converteriA first output terminal I, a first node a and a second node B.
The utility model discloses an use two independent secondary limits of three-winding transformer to supply power for two flying capacitors for the voltage of two flying capacitors is automatic to be followed 1/3, 2/3 times input voltage and realizes flying capacitor's clamping effect.
Converter, three winding transformer T of the above structurerSecondary side voltage uN21＝ui/3、uN22＝2uiAnd/3, according to the difference of the duty ratio D of the converter, the working conditions of the converter can be divided into three conditions that D is less than 1/3, D is more than or equal to 1/3 and less than 2/3 and D is more than or equal to 2/3, and the input voltage u is usediAnd the inductor current iLfAll are greater than zero (u)iFor the correct time, switch the tube S1b、S2b、S3b、S4b、S5b、S6bConstant conduction; s1a、S2aConducting in a high-frequency complementary manner; s3a、S4aConducting in a high-frequency complementary manner; s5a、S6aHigh frequency complementary conduction of S1a、S3a、S5aThe switching signals of the switching tubes are the same but are 120 degrees out of phase with each other. u. ofiWhen negative, the switch tube S1a、S2a、S3a、S4a、S5a、 S6aConstant conduction; s1b、S2bConducting in a high-frequency complementary manner; s3b、S4bConducting in a high-frequency complementary manner; s5b、S6bHigh frequency complementary conduction of S1b、S3b、S5bThe switching signals of the switching tubes are the same but are 120 degrees out of phase with each other), specifically as follows:
when D < 1/3, the switching tube timing and main waveforms are as shown in FIG. 2:
(1) switched mode 1[ t ]0—t1]
t0At any moment, switch tube S1a、S4a、S6aConduction, S2a、S3a、S5aAnd (6) turning off. At power source uiUnder the action of the inductor LfStored energy, current i thereofLfLinearly increasing, pressure drop u at G, E two pointsGE＝ui/3。
(2) Switched mode 2[ t ]1—t2]
t1At any moment, switch tube S2a、S4a、S6aConduction, S1a、S3a、S5aAnd (6) turning off. Inductor LfRelease energy, current i thereofLfLinearly decreasing, pressure drop u at G, E two pointsGE＝0。
(3) Switching mode 3[ t ]2—t3]
t2At any moment, switch tube S2a、S3a、S6aConduction, S1a、S4a、S5aAnd (6) turning off. At power source uiUnder the action of electricityFeeling LfStored energy, current i thereofLfLinearly increasing, pressure drop u at G, E two pointsGE＝ui/3。
(4) Switch mode 4[ t ]3—t4]
t3At any moment, switch tube S2a、S4a、S6aConduction, S1a、S3a、S5aAnd (6) turning off. Inductor LfRelease energy, current i thereofLfLinearly decreasing, pressure drop u at G, E two pointsGE＝0。
(5) Switching mode 5[ t ]4—t5]
t4At any moment, switch tube S2a、S4a、S5aConduction, S1a、S3a、S6aAnd (6) turning off. At power source uiUnder the action of the inductor LfStored energy, current i thereofLfLinearly increasing, pressure drop u at G, E two pointsGE＝ui/3。
(6) Switched mode 6[ t ]5—t6]
t5At any moment, switch tube S2a、S4a、S6aConduction, S1a、S3a、S5aAnd (6) turning off. Inductor LfRelease energy, current i thereofLfLinearly decreasing, pressure drop u at G, E two pointsGE＝0。
When 1/3 ≦ D < 2/3, the switching tube timing and main waveform are as shown in FIG. 3 (when D1/3, the voltage u across G, E is at this timeGEAnd an output voltage uoCoincident, input voltage of 1/3 times amplitude):
(1) switch mode 7[ t ]0—t1]
t0At any moment, switch tube S1a、S4a、S5aConduction, S2a、S3a、S6aAnd (6) turning off. At power source uiUnder the action of the inductor LfStored energy, current i thereofLfLinearly increasing, pressure drop u at G, E two pointsGE＝2ui/3。
(2) Switch mode 8 t1—t2]
t1At any moment, switch tube S1a、S4a、S6aConduction, S2a、S3a、S5aAnd (6) turning off. Inductor LfRelease energy, current i thereofLfLinearly decreasing, pressure drop u at G, E two pointsGE＝ui/3。
(3) Switch mode 9[ t ]2—t3]
t2At any moment, switch tube S1a、S3a、S6aConduction, S2a、S4a、S5aAnd (6) turning off. At power source uiUnder the action of the inductor LfStored energy, current i thereofLfLinearly increasing, pressure drop u at G, E two pointsGE＝2ui/3。
(4) Switching mode 10[ t ]3—t4]
t3At any moment, switch tube S2a、S3a、S6aConduction, S1a、S4a、S5aAnd (6) turning off. Inductor LfRelease energy, current i thereofLfLinearly decreasing, pressure drop u at G, E two pointsGE＝ui/3。
(5) Switched mode 11[ t ]4—t5]
t4At any moment, switch tube S2a、S3a、S5aConduction, S1a、S4a、S6aAnd (6) turning off. At power source uiUnder the action of the inductor LfStored energy, current i thereofLfLinearly increasing, pressure drop u at G, E two pointsGE＝2ui/3。
(6) Switching mode 12[ t ]5—t6]
t5At any moment, switch tube S2a、S4a、S5aConduction, S1a、S3a、S6aAnd (6) turning off. Inductor LfRelease energy, current i thereofLfLinearly decreasing, pressure drop u at G, E two pointsGE＝ui/3。
When 2/3 is less than or equal to D, the timing and main waveform of each switch tube are as shown in FIG. 4 (when D is 2)At/3, the voltage u across G, E at this timeGEAnd an output voltage uoCoincident, input voltage of 2/3 times amplitude):
(1) switching mode 13[ t ]0—t1]
t0At any moment, switch tube S1a、S3a、S5aConduction, S2a、S4a、S6aAnd (6) turning off. At power source uiUnder the action of the inductor LfStored energy, current i thereofLfLinearly increasing, pressure drop u at G, E two pointsGE＝ui。
(2) Switching mode 14[ t ]1—t2]
t1At any moment, switch tube S1a、S4a、S5aConduction, S2a、S3a、S6aAnd (6) turning off. Inductor LfRelease energy, current i thereofLfLinearly decreasing, pressure drop u at G, E two pointsGE＝2ui/3。
(3) Switching mode 15[ t ]2—t3]
t2At any moment, switch tube S1a、S3a、S5aConduction, S2a、S4a、S6aAnd (6) turning off. At power source uiUnder the action of the inductor LfStored energy, current i thereofLfLinearly increasing, pressure drop u at G, E two pointsGE＝ui。
(4) Switching mode 16[ t ]3—t4]
t3At any moment, switch tube S1a、S3a、S6aConduction, S2a、S4a、S5aAnd (6) turning off. Inductor LfRelease energy, current i thereofLfLinearly decreasing, pressure drop u at G, E two pointsGE＝2ui/3。
(5) Switched mode 17[ t ]4—t5]
t4At any moment, switch tube S1a、S3a、S5aConduction, S2a、S4a、S6aAnd (6) turning off. At power source uiUnder the action ofInductance LfStored energy, current i thereofLfLinearly increasing, pressure drop u at G, E two pointsGE＝ui。
(6) Switch mode 18[ t ]5—t6]
t5At any moment, switch tube S2a、S3a、S5aConduction, S1a、S4a、S6aAnd (6) turning off. Inductor LfRelease energy, current i thereofLfLinearly decreasing, pressure drop u at G, E two pointsGE＝2ui/3。
In addition, the self-following flying capacitor four-level AC-AC converter of the utility model can output the inductor LfThe front end obtains four levels of input voltage of 0, 1/3, 2/3 and 1 time, output voltage can be adjusted in a full duty ratio range, the control problem of flying capacitance of the multilevel converter can be avoided, and compared with the two levels, the voltage stress of the switching tube can be reduced to 1/3 times of the original voltage stress.
Example two:
referring to fig. 5, a four-level AC-AC converter, specifically in Boost functional mode, includes an AC input power uiAn input inductor LfFour-level conversion unit and three-winding transformer TrAn output filter capacitor CfAnd an AC load RoSaid AC input power uiAn input inductor LfFour-level conversion unit and output filter capacitor CfAnd an AC load RoAre connected in sequence;
the four-level conversion unit comprises a first four-quadrant switching tube S5And the second four-quadrant switching tube S3And the third four-quadrant switching tube S1And the fourth four-quadrant switching tube S2And the fifth and fourth quadrant switch tube S4And the sixth four-quadrant switching tube S6A first flying capacitor Cy1And a second flying capacitor Cy2；
The first four-quadrant switching tube S5And a second four-quadrant switching tube S3A first node A is formed between the first and second four-quadrant switching tubes S3And a third four-quadrant switchPipe S1A second node B is formed between the first and second four-quadrant switching tubes S1And a fourth four-quadrant switching tube S2A third node G is formed between the four-quadrant switching tube S2And a fifth four-quadrant switching tube S4Form a fourth node C therebetween, and the fifth four-quadrant switching tube S4And a sixth four-quadrant switching tube S6Form a fifth node D therebetween;
the first flying capacitor Cy1Connected across a second node B and a fourth node C, the second flying capacitor Cy2Is bridged between the first node A and the fifth node D;
the three-winding transformer TrPrimary winding N of1Are respectively connected to an output filter capacitor CfA first terminal and a second terminal of said three-winding transformer TrFirst secondary winding N21And a first flying capacitor Cy1In parallel, said three-winding transformer TrSecond secondary winding N22And a second flying capacitor Cy2Parallel connection;
the first four-quadrant switching tube S5One end of which is connected to the output filter capacitor CfThe first end point of (1), the first four-quadrant switching tube S5The other end of the first four-quadrant switching tube passes through a second four-quadrant switching tube S in sequence3And the third four-quadrant switching tube S1And the fourth four-quadrant switching tube S2And a fifth four-quadrant switching tube S4Is connected to the sixth four-quadrant switching tube S6One end of the sixth four-quadrant switching tube S6Are respectively connected to an AC input power source u of the converteriSecond output terminal E and output filter capacitor CfA second endpoint of (a);
the third node G is connected with the input inductor LfConnected to the converter AC input source uiIs provided.
Example three:
referring to fig. 6, a four-level AC-AC converter, particularly in Buck-Boost functional mode, includes an AC input power uiFour-level conversion unit and energy storage inductor LfThree windingsTransformer TrAn output filter capacitor CfAnd an AC load Ro；
The four-level conversion unit comprises a first four-quadrant switching tube S5And the second four-quadrant switching tube S3And the third four-quadrant switching tube S1And the fourth four-quadrant switching tube S2And the fifth and fourth quadrant switch tube S4And the sixth four-quadrant switching tube S6A first flying capacitor Cy1And a second flying capacitor Cy2；
The first four-quadrant switching tube S5And a second four-quadrant switching tube S3A first node A is formed between the first and second four-quadrant switching tubes S3And a third four-quadrant switching tube S1A second node B is formed between the first and second four-quadrant switching tubes S1And a fourth four-quadrant switching tube S2A third node G is formed between the four-quadrant switching tube S2And a fifth four-quadrant switching tube S4Form a fourth node C therebetween, and the fifth four-quadrant switching tube S4And a sixth four-quadrant switching tube S6Form a fifth node D therebetween;
the first flying capacitor Cy1Connected across a second node B and a fourth node C, the second flying capacitor Cy2Is bridged between the first node A and the fifth node D;
the three-winding transformer TrPrimary winding N of1Are respectively connected to an AC input power u of the converteriFirst output terminal I and output filter capacitor CfThe three-winding transformer TrFirst secondary winding N21And a first flying capacitor Cy1In parallel, said three-winding transformer TrSecond secondary winding N22And a second flying capacitor Cy2Parallel connection;
the first four-quadrant switching tube S5Is connected to an AC input power u of the converteriThe first output end point I of the first four-quadrant switching tube S5The other end of the first four-quadrant switching tube passes through a second four-quadrant switching tube S in sequence3And the third four-quadrant switching tube S1Fourth, theQuadrant switch tube S2And a fifth four-quadrant switching tube S4Is connected to the sixth four-quadrant switching tube S6One end of the sixth four-quadrant switching tube S6Is connected at the other end to an output filter capacitor CfA first endpoint of (a);
the third node G is connected with the energy storage inductor L through thefAre respectively connected to AC input power u of the converteriSecond output terminal E and output filter capacitor CfThe second endpoint of (1).
The second and third embodiments are self-following flying capacitor four-level Boost type and Buck-Boost type alternating-current converters obtained by interchanging the input end I, the output end O and the common ground end E.
The self-following flying capacitor AC-AC converter with any integer level can be obtained on the basis of the invention of the self-following flying capacitor four-level AC-AC converter.
The above-mentioned embodiments are only for illustrating the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and to implement the present invention, which should not be construed as limiting the scope of the present invention. All modifications made according to the spirit of the main technical scheme of the present invention shall be covered within the protection scope of the present invention.
Claims (9)
1. A four-level AC-AC converter, characterized by: the transformer comprises an alternating current input power supply, a three-winding transformer, a four-level conversion unit, an output filter and an alternating current load, wherein the alternating current input power supply, the four-level conversion unit, the output filter and the alternating current load are sequentially connected;
the four-level conversion unit comprises a first four-quadrant switching tube, a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube, a fifth four-quadrant switching tube, a sixth four-quadrant switching tube, a first flying capacitor and a second flying capacitor;
a first node is formed between the first four-quadrant switching tube and the second four-quadrant switching tube, a second node is formed between the second four-quadrant switching tube and the third four-quadrant switching tube, a third node is formed between the third four-quadrant switching tube and the fourth four-quadrant switching tube, a fourth node is formed between the fourth four-quadrant switching tube and the fifth four-quadrant switching tube, and a fifth node is formed between the fifth four-quadrant switching tube and the sixth four-quadrant switching tube;
the first flying capacitor is connected across the second node and the fourth node, and the second flying capacitor is connected across the first node and the fifth node;
two ends of a primary winding of the three-winding transformer are respectively connected to a first output end point and a second output end point of an alternating current input power supply of the converter, a first secondary winding of the three-winding transformer is connected with the first flying capacitor in parallel, and a second secondary winding of the three-winding transformer is connected with the second flying capacitor in parallel;
one end of the first four-quadrant switching tube is connected to a first output end point of the converter alternating-current input power supply, the other end of the first four-quadrant switching tube is connected to one end of a sixth four-quadrant switching tube through a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube and a fifth four-quadrant switching tube in sequence, and the other end of the sixth four-quadrant switching tube is connected to a second output end point of the converter alternating-current input power supply;
the first input end point of the output filter is connected to the third node, and the second input end point of the output filter is connected to the second output end point of the converter alternating current input power supply.
2. The four-level AC-AC converter according to claim 1, characterized in that: the first four-quadrant switching tube comprises a first power switching tube and a second power switching tube which are connected in series in an opposite direction;
the second four-quadrant switching tube comprises a third power switching tube and a fourth power switching tube which are connected in series in an opposite direction;
the third four-quadrant switching tube comprises a fifth power switching tube and a sixth power switching tube which are connected in series in an opposite direction;
the fourth four-quadrant switching tube comprises a seventh power switching tube and an eighth power switching tube which are connected in series in an opposite direction;
the fifth four-quadrant switching tube comprises a ninth power switching tube and a tenth power switching tube which are connected in series in an opposite direction;
the sixth four-quadrant switching tube comprises an eleventh power switching tube and a twelfth power switching tube which are connected in series in an opposite direction.
3. The four-level AC-AC converter according to claim 2, characterized in that: the first power switch tube, the second power switch tube, the third power switch tube, the fourth power switch tube, the fifth power switch tube, the sixth power switch tube, the seventh power switch tube, the eighth power switch tube, the ninth power switch tube, the tenth power switch tube, the eleventh power switch tube and the twelfth power switch tube are all IGBT switch tubes or MOSFET switch tubes.
4. The four-level AC-AC converter according to claim 1, characterized in that: the output filter comprises an output inductor and an output filter capacitor.
5. The four-level AC-AC converter according to claim 1, characterized in that: the turn ratio of a primary winding to a first secondary winding of the three-winding transformer is 3: 1;
the turn ratio of a primary winding to a second secondary winding of the three-winding transformer is 3: 2.
6. The four-level AC-AC converter according to claim 1, characterized in that: the dotted terminals of the primary side, the second secondary side and the first secondary side of the three-winding transformer are respectively connected to a first output end point, a first node and a second node of the converter alternating current input power supply.
7. A four-level AC-AC converter, characterized by: the transformer comprises an alternating current input power supply, an input inductor, a four-level conversion unit, a three-winding transformer, an output filter capacitor and an alternating current load, wherein the alternating current input power supply, the input inductor, the four-level conversion unit, the output filter capacitor and the alternating current load are sequentially connected;
the four-level conversion unit comprises a first four-quadrant switching tube, a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube, a fifth four-quadrant switching tube, a sixth four-quadrant switching tube, a first flying capacitor and a second flying capacitor;
a first node is formed between the first four-quadrant switching tube and the second four-quadrant switching tube, a second node is formed between the second four-quadrant switching tube and the third four-quadrant switching tube, a third node is formed between the third four-quadrant switching tube and the fourth four-quadrant switching tube, a fourth node is formed between the fourth four-quadrant switching tube and the fifth four-quadrant switching tube, and a fifth node is formed between the fifth four-quadrant switching tube and the sixth four-quadrant switching tube;
the first flying capacitor is connected across the second node and the fourth node, and the second flying capacitor is connected across the first node and the fifth node;
two ends of a primary winding of the three-winding transformer are respectively connected to a first end point and a second end point of the output filter capacitor, a first secondary winding of the three-winding transformer is connected with the first flying capacitor in parallel, and a second secondary winding of the three-winding transformer is connected with the second flying capacitor in parallel;
one end of the first four-quadrant switching tube is connected to a first end point of the output filter capacitor, the other end of the first four-quadrant switching tube is connected to one end of a sixth four-quadrant switching tube through a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube and a fifth four-quadrant switching tube in sequence, and the other end of the sixth four-quadrant switching tube is connected to a second output end point of the converter alternating-current input power supply and a second end point of the output filter capacitor respectively;
the third node is connected to the first output end point of the alternating current input power supply of the converter through the input inductor.
8. A four-level AC-AC converter, characterized by: the three-winding AC power supply comprises an AC input power supply, a four-level conversion unit, an energy storage inductor, a three-winding transformer, an output filter capacitor and an AC load;
the four-level conversion unit comprises a first four-quadrant switching tube, a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube, a fifth four-quadrant switching tube, a sixth four-quadrant switching tube, a first flying capacitor and a second flying capacitor;
a first node is formed between the first four-quadrant switching tube and the second four-quadrant switching tube, a second node is formed between the second four-quadrant switching tube and the third four-quadrant switching tube, a third node is formed between the third four-quadrant switching tube and the fourth four-quadrant switching tube, a fourth node is formed between the fourth four-quadrant switching tube and the fifth four-quadrant switching tube, and a fifth node is formed between the fifth four-quadrant switching tube and the sixth four-quadrant switching tube;
the first flying capacitor is connected across the second node and the fourth node, and the second flying capacitor is connected across the first node and the fifth node;
two ends of a primary winding of the three-winding transformer are respectively connected to a first output end point of an alternating current input power supply of the converter and a first end point of an output filter capacitor, a first secondary winding of the three-winding transformer is connected with a first flying capacitor in parallel, and a second secondary winding of the three-winding transformer is connected with a second flying capacitor in parallel;
one end of the first four-quadrant switching tube is connected to a first output end point of an alternating current input power supply of the converter, the other end of the first four-quadrant switching tube is connected to one end of a sixth four-quadrant switching tube through a second four-quadrant switching tube, a third four-quadrant switching tube, a fourth four-quadrant switching tube and a fifth four-quadrant switching tube in sequence, and the other end of the sixth four-quadrant switching tube is connected to a first end point of an output filter capacitor;
and the third node is respectively connected to a second output endpoint of the alternating current input power supply of the converter and a second endpoint of the output filter capacitor through the energy storage inductor.
9. Any integer level AC-AC converter extended based on the four-level AC-AC converter of any one of claims 1-8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920879729.9U CN210111864U (en) | 2019-06-12 | 2019-06-12 | Four-level AC-AC converter and any integer level AC-AC converter obtained by expanding four-level AC-AC converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920879729.9U CN210111864U (en) | 2019-06-12 | 2019-06-12 | Four-level AC-AC converter and any integer level AC-AC converter obtained by expanding four-level AC-AC converter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN210111864U true CN210111864U (en) | 2020-02-21 |
Family
ID=69565013
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920879729.9U Active CN210111864U (en) | 2019-06-12 | 2019-06-12 | Four-level AC-AC converter and any integer level AC-AC converter obtained by expanding four-level AC-AC converter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN210111864U (en) |
-
2019
- 2019-06-12 CN CN201920879729.9U patent/CN210111864U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Dusmez et al. | A fully integrated three-level isolated single-stage PFC converter | |
| CN107294392A (en) | A kind of bidirectional DC/DC converter | |
| CN101621247B (en) | Power factor correction circuit | |
| CN103944397A (en) | Boost type isolated DC/DC converter and control method thereof | |
| CN112928919B (en) | Isolated high-frequency resonant DC-DC converter with wide output voltage range and method | |
| CN106130352B (en) | The micro- inverter of intermediate current type double tube positive exciting and its numerical control device | |
| CN211127590U (en) | Phase-shifted full-bridge zero-voltage zero-current soft switching DC-DC converter | |
| CN105226929A (en) | A kind of change mode cascade converter | |
| CN109274264A (en) | A kind of boost type resonant switched capacitor converter of wide-voltage-regulation range | |
| CN107147303B (en) | Single-phase X-shaped staggered three-level alternating current voltage regulating circuit | |
| CN106899203B (en) | Forward five-level inverter | |
| CN102291020A (en) | Alternating-current push-pull conversion-single-diode rectification AC-DC (alternating current-to-direct current) converter | |
| Zhang et al. | Soft-switching single-stage current-fed full-bridge isolated converter for high power AC/DC applications | |
| CN109818494B (en) | High-gain voltage type quasi-Y source direct current-direct current converter | |
| CN209767394U (en) | self-following flying capacitor five-level AC-AC converter | |
| CN210111864U (en) | Four-level AC-AC converter and any integer level AC-AC converter obtained by expanding four-level AC-AC converter | |
| CN203339952U (en) | Switched-capacitor AC-AC converter | |
| CN107276393B (en) | High-voltage power supply circuit | |
| CN105429452A (en) | Common-mode rejection dual-Boost bridgeless PFC converter | |
| CN112366946B (en) | Resonant DC-DC converter | |
| CN214674908U (en) | Hybrid cascade type AC-AC converter | |
| CN103973129A (en) | Soft-switching power electronic transformer | |
| CN205195567U (en) | Novel LC series resonance DCDC converter and power electronic device | |
| CN204906192U (en) | Boost module is recommended to wide region full cut -off ring high efficiency | |
| CN103746563A (en) | Three-level direct current converter of ZVS (zero voltage switch) with dual-bridge wide load range and switch power supply |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |