[go: up one dir, main page]

CN114567184B - Three-phase-to-N-phase direct AC-AC converter based on three-phase transformer cascade connection - Google Patents

Three-phase-to-N-phase direct AC-AC converter based on three-phase transformer cascade connection Download PDF

Info

Publication number
CN114567184B
CN114567184B CN202210081093.XA CN202210081093A CN114567184B CN 114567184 B CN114567184 B CN 114567184B CN 202210081093 A CN202210081093 A CN 202210081093A CN 114567184 B CN114567184 B CN 114567184B
Authority
CN
China
Prior art keywords
phase
direct
cascading
output
chopper
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
Application number
CN202210081093.XA
Other languages
Chinese (zh)
Other versions
CN114567184A (en
Inventor
刘闯
蔡国伟
朱炳达
邵鑫铭
郭东波
裴忠晨
姜宇
孙赫阳
杨冬锋
刘士利
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Northeast Electric Power University
Original Assignee
Northeast Dianli University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Northeast Dianli University filed Critical Northeast Dianli University
Priority to CN202210081093.XA priority Critical patent/CN114567184B/en
Publication of CN114567184A publication Critical patent/CN114567184A/en
Application granted granted Critical
Publication of CN114567184B publication Critical patent/CN114567184B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

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
    • H02M5/00—Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases
    • H02M5/02—Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into DC
    • H02M5/04—Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into DC by static converters
    • H02M5/10—Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into DC by static converters using transformers
    • 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
    • H02M1/00—Details of apparatus for conversion
    • H02M1/12—Arrangements for reducing harmonics from AC input or output
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Ac-Ac Conversion (AREA)

Abstract

The invention discloses a three-phase-to-N-phase direct alternating current converter based on three-phase transformer cascading, which comprises one or more three-phase transformer cascading units, wherein the input end of each three-phase transformer cascading unit is connected with three-phase alternating current input voltage, the output end of each three-phase transformer cascading unit comprises N positive output ports V Z1…VZN and N negative output ports V F1…VFN, the adjacent three-phase transformer cascading units are connected with the positive output ports through the negative output ports, the N positive output ports of the first three-phase transformer cascading unit are respectively connected with the inductance end of one LC filter, the capacitance ends of the LC filters are connected with the negative output ports of the terminal three-phase transformer cascading unit in sequence, and N alternating current output ports are formed at the nodes where the inductances of the N LC filters are connected with the capacitances; the three-phase alternating current input voltage can be converted into N-phase alternating current output voltage, and the frequency, the amplitude and the phase of the output voltage are independently controllable.

Description

Three-phase-to-N-phase direct AC-AC converter based on three-phase transformer cascade connection
Technical Field
The invention belongs to the technical field of electric energy conversion, and particularly relates to a three-phase-to-N-phase direct type alternating current-to-alternating current converter based on three-phase transformer cascading.
Background
The research of the existing multiphase power transmission mode is limited to the multiple phases with the phase number of 3, such as 6, 12 and 24, which are equal. Because the multiphase transformation between the three phases and the multiple of 3 phases is easily achieved by changing the wiring mode of the three-phase transformer, in order to avoid complex transposition of the multiphase transmission line and ensure the parameter balance of each phase, the wires of each phase of the multiphase transmission line must be arranged into a regular polygon, which makes the suspension of the multiphase wires of 6 phases and more difficult, the structure of the pole tower is complex, and the cost of the line is increased. With the increase of the number of the line phases, the fault combination type of the multiphase power transmission line is rapidly increased, so that the analysis and calculation of faults are realized, and the difficulty is increased in the design and setting of relay protection. In addition, the circuit breaker in the multiphase power transmission system is complex in structure and high in interphase overvoltage multiple. The popularization and application of the six-phase and above multi-phase transmission mode are limited due to the defects.
In fact, a four-phase transmission system is a multiphase system closest to three phases, and is also the smallest possible even-phase system. The multi-phase power transmission system has the advantages of a multi-phase power transmission mode and overcomes the defects of the multi-phase power transmission. The four-phase transmission mode has the main advantages that: 1. the one-phase line is added, the space electromagnetic field distribution is more uniform, the conveying capacity is increased, the conveying power density of the line can be improved by reducing the line corridor, and the investment cost of conveying unit capacity is saved; 2. the four-phase line is even-numbered, the symmetry is good, the four-phase wires can be symmetrically hung on two sides of the single-column tower, and the tower structure is simple; 3. the four-phase line can adopt two adjacent phases to operate, so that the reliability and transient stability of the operation of the power transmission system can be improved; 4. the combination type of faults of the four-phase transmission line is far less than that of a six-phase transmission line or more multiphase transmission lines, and great difficulty is not increased to the design and setting of fault analysis and relay protection; 5. the four phases adopted in the open sea wind power energy transmission system have the same advantages, and the four phases can ensure that when one line is overhauled or one line fails, the rest three-phase line can work normally, so that the continuous energy transmission is ensured. Therefore, the four-phase system has excellent research value and development prospect due to the unique advantages. However, in the conventional manner, the transformer is not flexible enough to change three phases into four phases, so it is of great value to find a device for changing three phases into four phases and realizing interconnection between a three-phase system and a four-phase system.
Disclosure of Invention
The invention aims to provide a three-phase-to-N-phase direct type alternating-current converter based on three-phase transformer cascading, which can convert three-phase alternating-current input voltage into N-phase alternating-current output voltage, and the frequency, amplitude and phase of the output voltage are independently controllable.
The first technical scheme adopted by the invention is that the three-phase-to-N-phase direct alternating current converter based on three-phase transformer cascading comprises a plurality of three-phase transformer cascading units, wherein the input end of each three-phase transformer cascading unit is connected with three-phase alternating current input voltage, the output end of each three-phase transformer cascading unit comprises N positive output ports V Z1…VZN and N negative output ports V F1…VFN, N is not less than 3, the negative output ports V F1 to V FN of each three-phase transformer cascading unit are sequentially connected with the positive output ports V Z1 to V ZN of adjacent three-phase transformer cascading units on the right side of the three-phase transformer cascading unit, the N positive output ports of the first three-phase transformer cascading unit are respectively connected with the inductance end of one LC filter, the capacitance ends of the LC filters are sequentially connected with the negative output ports of the three-phase transformer cascading units on the tail end after being connected, and N alternating current output ports are formed at the nodes where the inductances and the capacitances of the N LC filters are connected.
The second technical scheme adopted by the invention is that the three-phase-to-N-phase direct type alternating current converter based on three-phase transformer cascading comprises a three-phase transformer cascading unit, wherein the input ends of the three-phase transformer cascading unit are connected with three-phase alternating current input voltages, the output ends of the three-phase transformer cascading unit comprise N positive output ports V Z1…VZN and N negative output ports V F1…VFN, the N positive output ports of the three-phase transformer cascading unit are respectively connected with the inductance end of one LC filter, the N negative output ports of the three-phase transformer cascading unit are respectively connected with the capacitance end of one LC filter, and N alternating current output ports are formed at the positions of the nodes where the inductances of the N LC filters are connected with the capacitance.
The invention is also characterized in that:
The three-phase transformer cascade unit comprises a three-phase multi-winding transformer and 3N cascade direct AC/AC choppers, wherein each iron core column of the three-phase multi-winding transformer is connected with one primary winding and a plurality of secondary windings, positive polarity wires of each primary winding are respectively connected with one phase of U-phase, V-phase and W-phase of alternating-current input voltage, negative polarity wires of the three primary windings are in star connection or angle connection, the secondary windings on each iron core column are equally connected with N cascade direct AC/AC chopper input ends, output positive poles of the N cascade direct AC/AC choppers corresponding to the iron core column connected with the U-phase are respectively connected with one positive pole output port, N cascade direct AC/AC choppers corresponding to the iron core column connected with the U-phase are sequentially connected with N cascade direct AC/AC choppers corresponding to the iron core column of the V-phase, N cascade direct AC/AC choppers corresponding to the iron core column of the V-phase are sequentially connected with N cascade direct AC/AC chopper output positive poles corresponding to the iron core column of the V-phase, and N cascade direct AC/AC chopper output negative poles of the N cascade direct AC chopper output poles corresponding to the iron core column of the V-phase are sequentially connected with N cascade AC chopper output ports of the N direct AC/AC chopper output ports corresponding to the N cascade AC output ports of the iron core column of the V-phase.
Each cascade direct type AC/AC chopper comprises a plurality of direct type AC/AC choppers, the anode and the cathode of the input end of each direct type AC/AC chopper are connected with the anode and the cathode of the output end of one secondary winding, the plurality of direct type AC/AC choppers are connected in a mode that the output cathode is connected with the output anode of the adjacent direct type AC/AC chopper, the output anode of the head end direct type AC/AC chopper is used as the output anode of the cascade direct type AC/AC chopper, and the output cathode of the tail end direct type AC/AC chopper is used as the output cathode of the cascade direct type AC/AC chopper.
Each cascade direct type AC/AC chopper is a direct type AC/AC chopper, the anode and the cathode of the input end of the direct type AC/AC chopper are connected with the anode and the cathode of the output end of the secondary winding, the anode of the output end of the direct type AC/AC chopper is used as the output anode of the cascade direct type AC/AC chopper, and the cathode of the output end of the direct type AC/AC chopper is used as the output cathode of the cascade direct type AC/AC chopper.
The invention has the beneficial effects that:
(1) The invention can realize the conversion of three-phase alternating current into N-phase alternating current, and the frequency, amplitude and phase of the output voltage are all independently controllable.
(2) The invention can realize the bidirectional flow of power and interconnect the three-phase system and the N-phase system.
(3) According to the invention, the input sides of the cascade direct type AC/AC converters are coupled through the magnetic circuit of the transformer, so that the current harmonic elimination can be realized, and the current harmonic elimination is prevented from being introduced into the primary side of the transformer, so that the harmonic pollution is caused to the input current.
(4) The invention does not contain a direct-current capacitor, has lower cost and volume, does not have the problems of capacitor voltage equalizing or capacitor starting, and reduces the complexity of a control system.
Drawings
FIG. 1 is a topological structure diagram of a three-phase AC-to-N AC-to-DC direct AC-to-AC converter based on three-phase transformer cascading;
fig. 2 is an internal structural view of a three-phase transformer cascade unit in the present invention;
FIG. 3 is an internal structure of a cascaded direct AC/AC chopper of a three-phase transformer cascade unit of the present invention;
fig. 4 is a schematic diagram of the internal structure of the present invention when n=4 using a single three-phase transformer cascade unit;
FIG. 5 is a waveform diagram of an input/output voltage of a three-phase AC-to-N-to-DC direct AC-to-AC converter operating in a down-conversion mode based on three-phase transformer cascading in accordance with the present invention;
fig. 6 is a waveform diagram of input and output voltages of the three-phase ac-to-N-ac direct ac-to-ac converter of the present invention operating in an up-conversion mode based on three-phase transformer cascading.
Detailed Description
The invention will be described in detail below with reference to the drawings and the detailed description.
The invention relates to a three-phase-to-N-phase direct alternating current converter based on three-phase transformer cascading, which adopts a first technical scheme as shown in figure 1 and comprises a plurality of three-phase transformer cascading units, wherein the input end of each three-phase transformer cascading unit is connected with three-phase alternating current input voltage, the output end of each three-phase transformer cascading unit comprises N positive output ports V Z1…VZN and N negative output ports V F1…VFN, N is not smaller than 3, the negative output ports V F1 to V FN of each three-phase transformer cascading unit are sequentially connected with the positive output ports V Z1 to V ZN of adjacent three-phase transformer cascading units on the right side of the three-phase transformer cascading unit, the N positive output ports of the first three-phase transformer cascading unit are respectively connected with the inductance end of one LC filter, the capacitance ends of the LC filters are sequentially connected with the negative output ports of the terminal three-phase transformer cascading unit after being connected, and N alternating current output ports are formed at the node where the inductance and the capacitance of the N LC filters are connected.
The second technical scheme is that the three-phase transformer cascade unit comprises a three-phase transformer cascade unit, wherein the input ends of the three-phase transformer cascade unit are connected with three-phase alternating current input voltages, the output ends of the three-phase transformer cascade unit comprise N positive output ports V Z1…VZN and N negative output ports V F1…VFN, the N positive output ports of the three-phase transformer cascade unit are respectively connected with the inductance end of one LC filter, the N negative output ports of the three-phase transformer cascade unit are respectively connected with the capacitance end of one LC filter, and N alternating current output ports are formed at the nodes where the inductance of the N LC filters are connected with the capacitance.
As shown in fig. 2, the three-phase transformer cascade unit includes a three-phase multi-winding transformer and 3N cascade direct AC/AC choppers, each core limb of the three-phase multi-winding transformer is connected with a primary winding and a plurality of secondary windings, the turns ratio of the primary winding and the secondary winding on each core limb is the same, positive polarity wires of each primary winding are respectively connected with one of the phases of the AC input voltage U-phase, V-phase and W-phase, the negative polarity wires of the three primary windings are star-connected or angle-connected, the secondary windings on each core limb are equally connected with N cascade direct AC/AC chopper input ends, the output positive poles of the N cascade direct AC/AC choppers corresponding to the core limb of the U-phase are respectively connected with an anode output port, as N cascade direct AC/AC choppers output negative poles corresponding to the core limb of the three-phase transformer are sequentially connected with N cascade direct AC/AC chopper output negative poles corresponding to the N cascade direct AC/AC chopper output poles of the V-phase core limb, and the N cascade direct AC/AC chopper output negative poles corresponding to the core limb of the V-phase core limb is sequentially connected with N cascade direct AC/AC chopper output ports corresponding to the N cascade output ports of the N direct AC/AC chopper output poles of the V-phase.
The first scheme of each cascade direct type AC/AC chopper is that, as shown in fig. 3, the cascade direct type AC/AC chopper comprises a plurality of direct type AC/AC choppers, the anode and the cathode of the input end of each direct type AC/AC choppers are connected with the anode and the cathode of the output end of one secondary winding, the plurality of direct type AC/AC choppers are connected with the output anode of the adjacent direct type AC/AC choppers through the output cathode, the output anode of the head direct type AC/AC choppers is used as the output anode of the cascade direct type AC/AC choppers, and the output cathode of the tail direct type AC/AC choppers is used as the output cathode of the cascade direct type AC/AC choppers.
The second scheme of each cascade direct type AC/AC chopper is that the direct type AC/AC chopper is characterized in that the positive electrode and the negative electrode of the input end of the direct type AC/AC chopper are connected with the positive electrode and the negative electrode of the output end of the secondary winding, the positive electrode of the output end of the direct type AC/AC chopper is used as the output positive electrode of the cascade direct type AC/AC chopper, and the negative electrode of the output end of the direct type AC/AC chopper is used as the output negative electrode of the cascade direct type AC/AC chopper.
In order to more clearly demonstrate the working principle of the present invention, mathematical deductions are made by taking the structure shown in fig. 4 as an example. Fig. 4 shows output four-phase alternating current (n=4) and employs a single three-phase transformer cascade unit, and the cascade direct AC/AC chopper in the three-phase transformer cascade unit employs a single direct AC/AC chopper. The input three-phase alternating voltages are defined as U phase, V phase and W phase, the output voltages are defined as A phase, B phase, C phase and D phase, the synthetic principle of the A phase output voltage V OA is taken as an example for illustration, the B phase, the C phase and the D phase are similar symmetrically, the cascade direct type AC/AC chopper corresponding to the U phase serving as the input voltage in each three-phase transformer cascade unit is U a、Ub、Uc、Ud, the cascade direct type AC/AC chopper corresponding to the V phase is V a、Vb、Vc、Vd, and the cascade direct type AC/AC chopper corresponding to the W phase is W a、Wb、Wc、Wd.
Let the three-phase input voltage be formula (1), expressed as:
Where ω 1 is the angular frequency of the input voltage and V in is the amplitude of the input voltage. The direct AC/AC chopper U a employs a modulated wave D U, the direct AC/AC chopper V a employs a modulated wave D V, and the direct AC/AC chopper W a employs a modulated wave D W. The modulated wave D U、DV、DW is of formula (2).
Wherein ω 2 is the angular frequency of the output voltage V OA, V D is the amplitude of the three modulated waves, and the value is 0 to 1.Is the initial phase difference of the output voltage relative to the input voltage. Since the output voltage of the direct AC/AC chopper U a、Va、Wa is in a series relationship and the turns ratios of the windings of each phase are identical, the output voltage V OA can be expressed as formula (3):
VOA＝UU·DU+UV·DV+UW·DW (3)
substitution of formulas (1) - (2) into formula (3) can be obtained
V OB、VOC、VOD is the same as the expression (4), and the expression of the final four-phase alternating current output voltage is the expression (5).
As can be seen from the formula (5), the invention can output three-phase voltages with independently controllable frequency, amplitude and phase.
Taking a transformer U-phase iron core column as an example, analyzing harmonic current, and setting an output current as a formula (6). The input sides of the unipolar direct AC/AC choppers U a、Ub、Uc and U d are coupled by a U-phase core leg magnetic circuit, and the coupling current can be represented by formula (7).
Where I m is the magnitude of the four-phase output current. I U is a U-phase input current expression. The coupled current frequency is seen to be omega 1, which is the same frequency as the input voltage current. According to the invention, the input sides of the cascade direct type AC/AC converters are coupled through the magnetic circuit of the transformer, so that the current harmonic elimination can be realized, and the current harmonic elimination is prevented from being introduced into the primary side of the transformer, so that the harmonic pollution is caused to the input current.
Fig. 5 shows waveforms of the present invention operating in a down-conversion mode. The first grid shows a waveform of the input three-phase voltage U U,UV,UW. The effective value of the input three-phase voltage is 220V and the frequency is 50Hz. The second grid shows a waveform of the output four-phase voltage V OA,VOB,VOC,VOD. The effective value of the output four-phase voltage is 110V and the frequency is 15Hz.
Fig. 6 shows waveforms of the present invention operating in the up-conversion mode. The first grid shows a waveform of the input three-phase voltage U U,UV,UW. The effective value of the input three-phase voltage is 220V and the frequency is 50Hz. The second grid shows a waveform of the output four-phase voltage V OA,VOB,VOC,VOD. The effective value of the output four-phase voltage is 110V and the frequency is 100Hz.
Through the mode, the three-phase-to-N-phase direct type alternating current/alternating current converter is characterized by comprising a three-phase-center type multi-winding transformer, 3*N cascaded direct type AC/AC choppers and N LC filters. Each cascaded direct AC/AC chopper includes one or more direct AC/AC choppers. The invention can convert the three-phase alternating current input voltage into the N-phase alternating current output voltage, and the frequency, the amplitude and the phase of the output voltage are all independently controllable. The input sides of the cascade direct type AC/AC converters are coupled through the magnetic circuit of the transformer, so that current harmonic elimination can be realized, and harmonic pollution to input current caused by introducing the current harmonic elimination into the primary side of the transformer is avoided. In addition, the invention can realize the bidirectional flow of energy and can interconnect a three-phase system and an N-phase system.

Claims (4)

1. The three-phase-to-N-phase direct alternating current converter based on three-phase transformer cascading is characterized by comprising a plurality of three-phase transformer cascading units, wherein the input ends of the three-phase transformer cascading units are connected with three-phase alternating current input voltages, the output ends of the three-phase transformer cascading units comprise N positive output ports V Z1…VZN and N negative output ports V F1…VFN, N is not smaller than 3, the negative output ports V F1 to V FN of each three-phase transformer cascading unit are sequentially connected with the positive output ports V Z1 to V ZN of adjacent three-phase transformer cascading units on the right side of the three-phase transformer cascading unit, the N positive output ports of the first three-phase transformer cascading unit are respectively connected with the inductance end of one LC filter, the capacitance ends of the LC filters are sequentially connected with the negative output ports of the three-phase transformer cascading units on the tail end after being connected, and N alternating current output ports are formed at the positions of the inductance and capacitance connection nodes of the LC filters.
2. The three-phase-to-N-phase direct AC/AC converter based on three-phase transformer cascading according to claim 1, wherein the three-phase transformer cascading unit comprises a three-phase core type multi-winding transformer and 3N cascading direct AC/AC choppers, each core limb of the three-phase core type multi-winding transformer is connected with a primary winding and a plurality of secondary windings, positive polarity wires of each primary winding are respectively connected with one of the phases of the alternating-current input voltage U-phase, V-phase and W-phase, the negative polarity wires of the three primary windings are star-connected or angle-connected, the secondary windings on each core limb are equally connected with N cascading direct AC/AC chopper input ends, output positive poles of the N cascading direct AC/AC choppers corresponding to the core limb of the U-phase are respectively connected with one positive pole output port, the N cascading direct AC/AC choppers corresponding to the core limb of the U-phase are used as N positive pole output ports V Z1…VZN of the three-phase transformer cascading unit, the output negative poles of the N cascading direct AC/AC choppers corresponding to the core limb of the U-phase are respectively connected with N cascading direct AC/AC chopper output negative poles corresponding to the core limb of the V-phase, the N cascading direct AC/AC chopper output negative pole of the core limb of the U-phase corresponds to the N cascading AC chopper output ports corresponding to the N cascading AC/AC output ports of the N cascading AC/AC core limb of the N-phase.
3. The three-phase-to-N-phase direct AC/AC converter according to claim 2, wherein each of the cascaded direct AC/AC choppers comprises a plurality of direct AC/AC choppers, wherein each of the direct AC/AC choppers has an input end connected to an output end of the secondary winding, the plurality of direct AC/AC choppers are connected by an output end connected to an output end of an adjacent direct AC/AC chopper, the output end of the leading direct AC/AC chopper is used as an output end of the cascaded direct AC/AC choppers, and the output end of the trailing direct AC/AC choppers is used as an output end of the cascaded direct AC/AC choppers.
4. The three-phase-to-N-phase direct AC-to-AC converter of claim 2, wherein each of said cascaded direct AC/AC choppers is a direct AC/AC chopper having an input positive and a negative pole connected to an output positive and a negative pole of the secondary winding, an output positive pole of said direct AC/AC chopper being an output positive pole of said cascaded direct AC/AC chopper, and an output negative pole of said direct AC/AC chopper being an output negative pole of said cascaded direct AC/AC chopper.
CN202210081093.XA 2022-01-24 2022-01-24 Three-phase-to-N-phase direct AC-AC converter based on three-phase transformer cascade connection Active CN114567184B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210081093.XA CN114567184B (en) 2022-01-24 2022-01-24 Three-phase-to-N-phase direct AC-AC converter based on three-phase transformer cascade connection

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210081093.XA CN114567184B (en) 2022-01-24 2022-01-24 Three-phase-to-N-phase direct AC-AC converter based on three-phase transformer cascade connection

Publications (2)

Publication Number Publication Date
CN114567184A CN114567184A (en) 2022-05-31
CN114567184B true CN114567184B (en) 2024-09-27

Family

ID=81713142

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210081093.XA Active CN114567184B (en) 2022-01-24 2022-01-24 Three-phase-to-N-phase direct AC-AC converter based on three-phase transformer cascade connection

Country Status (1)

Country Link
CN (1) CN114567184B (en)

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4793096B2 (en) * 2006-05-24 2011-10-12 株式会社明電舎 High voltage AC direct power converter
CN103219896B (en) * 2013-04-09 2015-01-07 湖南大学 Three-phase high-voltage cascade type AC (Alternating Current) -DC (Direct Current) -AC bidirectional converter and control method thereof
CN108011527A (en) * 2017-12-27 2018-05-08 北京金风科创风电设备有限公司 Converter, direct-drive wind generating set and power transmission system
US10998825B2 (en) * 2018-02-12 2021-05-04 The Texas A&M University System Method and apparatus for medium-voltage electronic power conversion
GB201803765D0 (en) * 2018-03-09 2018-04-25 Rolls Royce Plc AC--AC Converter and method of operation
CN113872452A (en) * 2021-07-15 2021-12-31 东北电力大学 A direct AC-AC converter based on three-phase core multi-winding transformer

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Multi-port medium-frequency PET topology for integratingphotovoltaic generation with battery storage;Xuejiao Li，et al;《IET Renewable Power Generation》;20240417;第1-7页 *

Also Published As

Publication number Publication date
CN114567184A (en) 2022-05-31

Similar Documents

Publication Publication Date Title
EP3082212B1 (en) Tripolar flexible direct-current power transmission system and method
CN104685771B (en) Power-converting device
US9502991B2 (en) Hybrid converter and wind power generating system
CN111446866B (en) Through-in-phase traction power supply system based on balance transformer and four-port MMC
CN104079184A (en) Wind power converter based on bipolar direct-current structure
CN101856979B (en) A common-phase power supply device for electrified railway
CN102570491A (en) Multilevel power converter or inverter arrangement using h bridges
CN106452133A (en) Core converter for building bipolar DC microgrid and control method of core converter
CN115411964B (en) A marine microgrid inverter, modulation strategy and control method
CN114977859B (en) Three-phase N-module cascading type unidirectional energy flow multi-level frequency converter and control method
CN104601001A (en) Current conversion device and current conversion system for wind generating set
CN110247416B (en) Multi-port DC flexible multi-state switch device based on bifurcated bridge arm structure
CN112952845A (en) Low-frequency power transmission system with transformer isolation and control method thereof
CN106026685A (en) Topological structure of three-phase power electronic transformer employing low-fluctuation DC bus capacitors
CN113726136A (en) Conversion device
CN214707171U (en) Low-frequency power transmission system with transformer isolation
CN110829845A (en) Power electronic transformer topology with power self-balancing capability and its control method
CN112072704B (en) Medium-voltage high-capacity wind power generation converter topology
WO2018091065A1 (en) A modular multilevel converter for use in a high voltage traction system
CN114553047B (en) Three-phase alternating current-to-direct current converter based on three-phase transformer cascading
CN114567184B (en) Three-phase-to-N-phase direct AC-AC converter based on three-phase transformer cascade connection
CN218771787U (en) DC transformer of tandem type module
CN114553014B (en) Pulse width modulation method for synthesizing multiphase full-parameter controllable alternating voltage by three-phase alternating current
CN113726137A (en) Conversion device
CN114553013B (en) Three-phase-to-N-phase alternating current direct type alternating current-to-alternating current converter based on single-phase transformer cascading

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant