CN103457468A - High voltage direct current-direct current transformer - Google Patents
High voltage direct current-direct current transformer Download PDFInfo
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- CN103457468A CN103457468A CN2013103331798A CN201310333179A CN103457468A CN 103457468 A CN103457468 A CN 103457468A CN 2013103331798 A CN2013103331798 A CN 2013103331798A CN 201310333179 A CN201310333179 A CN 201310333179A CN 103457468 A CN103457468 A CN 103457468A
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Abstract
The invention discloses a high voltage direct current-direct current transformer. The high voltage DC-DC transformer comprises a cascaded modularized current transformer, a duplex-winding medium-low frequency sine-wave transformer and an input parallel-connection modularized current transformer. The cascaded modularized current transformer comprises two bridge arms, and the upper half bridge arm and the lower half bridge arm of the first bridge arm respectively comprise a capacitor bank. The upper half bridge arm and the lower half bridge arm of the second bridge arm respectively comprise two half-bridge topology power modules and one reactor. The duplex-winding medium-low frequency sine-wave transformer comprises a high voltage input winding and a lower voltage output winding, and the two ends of the high voltage input winding are connected with contacts of the two bridge arms respectively. The input parallel-connection modularized current transformer comprises at least one current transformer sub-module of the same structure, wherein the input end of each sub-module is connected with the low voltage output winding, and the output ends of the sub-modules are connected in series or in parallel or in the hybrid mode of series connection and parallel connection. The transformer of the structure has the advantages of being high in transmission capacity, high in efficiency and low in cost and is very significant for accelerating the utilization and marketalization process of the DC-DC transformer.
Description
Technical field
The present invention relates to the device of a kind of high voltage direct current-direct current energy conversion, transmission, particularly a kind of high voltage direct current-commutator transformer.
Background technology
High voltage direct current transmission (HVDC) has the characteristics such as the transmission power capacity is large, loss is little, fed distance is far away, good stability, has broad application prospects.In the future high voltage direct current transmission to be directly applied to power consumption equipment in order adapting to, need to have and exchange the functionally similar direct current transformation device of isolating transformer, high voltage direct current is converted to the low-voltage DC that power consumption equipment requires that meets of isolation.
Because the withstand voltage of single power semiconductor is normally limited, so single power semiconductor can't directly apply to the high voltage occasion.In order to realize that low voltage power devices can be applied in the high voltage occasion, usually adopt following several method: 1) multilevel converter; 2) a plurality of power semiconductor serial connection technologies; 3) a plurality of power model serial connection technologies.
Document " Dragan Jovcic. ' Bidirectional; High-Power DC Transformer ' .IEEE Transactions on Power Delivery; Vol.24; No.4; pp:2276-2283, October2009 " adopts Thyristors in series technology, harmonic technology to realize powerful DC converting and transmission.But high-pressure side and low-pressure side do not have electrical isolation, high-pressure side and low-pressure side thyristor valve group are all born high side voltage, have increased equipment cost.In addition, the LC resonant circuit produces larger reactive capability in the course of the work, has increased place capacity and line loss, has reduced conversion efficiency.
Chinese patent application 201010117551.8 has related to a kind of high voltage direct current-direct current power electronic transformer, and this commutator transformer consists of tandem type Modularized current transformer, double winding intermediate frequency or high frequency transformer and a full-control type H bridge.Produce intermediate frequency or the high frequency square wave voltage of many level by the tandem type Modularized current transformer, double winding intermediate frequency or high frequency transformer are realized voltage transformation and the power transmission of DC-to-DC, and full-control type H bridge converts the secondary square-wave voltage of intermediate frequency or high frequency transformer to direct voltage.
Chinese patent application 200810024744.1 has related to a kind of based on full-bridge topologies input series and output parallel automatically equalizing voltage commutator transformer, adopts the topological structure of the commutator transformer power model input series and output parallel of a plurality of full-bridge topologies.Utilize input series and output parallel structure and the effect of transformer side edge clamp, automatically realize that each module input side all presses.
In Chinese patent application 201010117551.8 and 200810024744.1, all adopted intermediate frequency or high frequency square wave transformer to carry out electrical isolation, voltage transformation and power transmission.But available intermediate frequency or high frequency square wave transformer efficiency capacity is difficult to reach more than up to a hundred kilowatts at present, limited to a certain extent the application of this type of commutator transformer.
Based on above analysis, the high side switch device of high voltage direct current-commutator transformer exists problem withstand voltage and that all press at present, and the problem of existing DC-to-DC transformer transmission capacity deficiency, haves much room for improvement.
Summary of the invention
Purpose of the present invention, be to provide a kind of high voltage direct current-commutator transformer, and it has the advantages that transmission capacity is large, efficiency is high, cost is low, significant to the practical and commercialization of accelerating high voltage direct current-commutator transformer.
In order to reach above-mentioned purpose, solution of the present invention is:
A kind of high voltage direct current-commutator transformer, comprise the tandem type Modularized current transformer, the sinusoidal wave transformer of double winding medium and low frequency and input parallel modular current transformer;
Described tandem type Modularized current transformer comprises two brachium pontis, and wherein, upper and lower half brachium pontis of the first brachium pontis respectively contains a capacitor group, and the two is connected on the contact of the first brachium pontis; First brachium pontis of the second brachium pontis by head to tail connect successively half-bridge topology power model and 1 reactor of at least 2 forwards, and second brachium pontis by head to connect the successively half-bridge topology power model of 1 reactor and at least 2 forwards of tail, and 2 reactors in upper and lower half brachium pontis are connected on the contact of the second brachium pontis; The head end of two brachium pontis connects the high-pressure side positive pole jointly, and tail end connects the high-pressure side negative pole jointly;
The sinusoidal wave transformer of described double winding medium and low frequency comprises 1 high input voltage winding and 1 low pressure output winding, and the two ends of high input voltage winding connect respectively the contact of first and second brachium pontis;
Described input parallel modular current transformer comprises the current transformer submodule that at least one structure is identical, and the input of each current transformer submodule all is connected with the low pressure output winding of the sinusoidal wave transformer of double winding medium and low frequency, and the output of all current transformer submodules requires the connected mode of selecting series, parallel or connection in series-parallel to mix according to the low-pressure side electric pressure.
Above-mentioned half-bridge topology power model comprises two turn-off devices with anti-paralleled diode and an electric capacity, first and second turn-off device forward is connected in series, again with Capacitance parallel connection, the tie point of described first and second turn-off device is as the positive pole of half-bridge topology power model, and the negative pole of the second turn-off device is as the negative pole of half-bridge topology power model.
Above-mentioned current transformer submodule comprises passive filter module and the power conversion module that order is in series, wherein, passive filter module adopts LC filter circuit or LCL filter circuit, and the power conversion module adopts two level half-bridge topologys, two Level Full Bridge topologys, many level half-bridges topology or many Level Full Bridges topology.
After adopting such scheme, the present invention utilizes existing power model serial connection technology and the sinusoidal wave transformer of double winding medium and low frequency, can solve well withstand voltage, the voltage-sharing of high side switch device of high voltage direct current-commutator transformer and the problem of existing DC-to-DC transformer transmission capacity deficiency, significant to the practical and commercialization of accelerating high voltage direct current-commutator transformer; Adopt the module serial connection technology can expand flexibly the electric pressure of transformer; The power capacity of the sinusoidal wave two winding transformer of medium and low frequency adopt the sinusoidal wave transformer of double winding medium and low frequency can realize electrical isolation, voltage transformation and the power transmission of high-pressure side and low-pressure side, more than can reach the MW level simultaneously.
The accompanying drawing explanation
Fig. 1 is overall structure figure of the present invention;
Fig. 2 is that in the present invention, the current transformer submodule adopts two level half-bridge LC filtering topology diagrams;
Fig. 3 is that in the present invention, the current transformer submodule adopts two level half-bridge LCL filtering topology diagrams;
Fig. 4 is that in the present invention, the current transformer submodule adopts two Level Full Bridge LC filtering topology diagrams;
Fig. 5 is that in the present invention, the current transformer submodule adopts two Level Full Bridge LCL filtering topology diagrams;
Fig. 6 is that in the present invention, the current transformer submodule adopts three level neutral point clamp half-bridge LC filtering topology diagrams;
Fig. 7 is that in the present invention, the current transformer submodule adopts three level neutral point clamp half-bridge LCL filtering topology diagrams;
Fig. 8 is that in the present invention, the current transformer submodule adopts three level striding capacitance half-bridge LC filtering topology diagrams;
Fig. 9 is that in the present invention, the current transformer submodule adopts three level striding capacitance half-bridge LCL filtering topology diagrams;
Figure 10 is the equivalent control method schematic diagram of cascade formula Modularized current transformer of the present invention;
Wherein, (a) mean U
acvoltage oscillogram, (b) mean U
a1voltage oscillogram, (c) mean U
a2voltage oscillogram.
Embodiment
Below with reference to accompanying drawing, technical scheme of the present invention is elaborated.
As shown in Figure 1, the invention provides a kind of high voltage direct current-commutator transformer, comprise tandem type Modularized current transformer 1, the sinusoidal wave transformer 2 of double winding medium and low frequency and input parallel modular current transformer 3, below introduce respectively.
Described tandem type Modularized current transformer 1 comprises two brachium pontis 11,12, and wherein, upper and lower half brachium pontis of brachium pontis 11 respectively contains capacitor group C1, a C2, and upper and lower half brachium pontis is connected on the contact of brachium pontis 11; It is natural number that upper and lower half brachium pontis of brachium pontis 12 respectively comprises M(M, and M>=2) individual half-bridge topology power model and 1 reactor, described half-bridge topology power model comprises two T of the turn-off device with anti-paralleled diode
11, T
12and capacitor C
11, concrete connected mode is: turn-off device T
11, T
12forward is connected in series, then with capacitor C
11parallel connection, described turn-off device T
11, T
12tie point as the positive pole of half-bridge topology power model, and T
12negative pole as the negative pole of half-bridge topology power model.In described brachium pontis 12, first brachium pontis by head to tail connect successively half-bridge topology power model and 1 reactor of M forward, and second brachium pontis by head to connect the successively half-bridge topology power model of 1 reactor and M forward of tail, and 2 reactors in upper and lower half brachium pontis are connected on the contact of brachium pontis 12.The head end of brachium pontis 11,12 connects the high-pressure side positive pole jointly, and tail end connects the high-pressure side negative pole jointly.
The sinusoidal wave transformer 2 of described double winding medium and low frequency comprises 1 high input voltage winding and 1 low pressure output winding, and wherein, the two ends of high input voltage winding connect respectively the contact of brachium pontis 11,12.
Described input parallel modular current transformer 3 comprises that N(N is natural number, and the current transformer submodule that N >=1) individual structure is identical, and the input of each current transformer submodule all is connected with the low pressure output winding of the sinusoidal wave transformer 2 of double winding medium and low frequency, and the output of all current transformer submodules requires the connected mode of selecting series, parallel or connection in series-parallel to mix according to the low-pressure side electric pressure.
Described current transformer submodule comprises passive filter module and the power conversion module that order is in series, wherein, passive filter module can adopt LC filter circuit or LCL filter circuit, and the power conversion module can adopt two level half-bridge topologys, two Level Full Bridge topologys, many level half-bridges topology or many Level Full Bridges topology.Comparatively typical Modularized current transformer topological structure has two level half-bridge LC filtering topologys (as Fig. 2), two level half-bridge LCL filtering topologys (as Fig. 3), two Level Full Bridge LC filtering topologys (as Fig. 4), two Level Full Bridge LCL filtering topologys (as Fig. 5), three level neutral point clamp half-bridge LC filtering topologys (as Fig. 6), three level neutral point clamp half-bridge LCL filtering topologys (as Fig. 7), three level striding capacitance half-bridge LC filtering topologys (as Fig. 8), three level striding capacitance half-bridge LCL filtering topologys (as Fig. 9); The left side of earlier figures 2 to Fig. 9 connects DC terminal, and right side connects to exchange holds.
When the present invention works, tandem type Modularized current transformer 1 is shaped to the medium and low frequency sine voltage by direct voltage; The sinusoidal wave transformer 2 of described double winding medium and low frequency carries out medium and low frequency and send energy, voltage transformation and electrical isolation, and the medium and low frequency frequency range is 30Hz～500Hz; Described input parallel modular current transformer 3 is reduced into direct voltage by the medium and low frequency sine voltage, is exported.
The present invention is when steady operation, and the high-pressure side DC bus-bar voltage is U
dc, the upper and lower half brachium pontis capacitor group both end voltage in brachium pontis 11 is U
dc/ 2, the voltage in upper and lower half brachium pontis in brachium pontis 12 on half-bridge topology power model clamping capacitance is U
dc/ M, that is: in the upper and lower half brachium pontis capacitor group voltage sum in brachium pontis 11, brachium pontis 12, the half-bridge topology power model clamping capacitance voltage sum of upper and lower half brachium pontis all equals DC bus-bar voltage U
dc, simultaneously, due to the error of discrete control algolithm and the nonlinear characteristic of switching device and magnetic core element, cause capacitor group voltage U
ckwith half-bridge topology power model clamping capacitance voltage U
cxhave certain fluctuation, general control is at U
dc/ 2-H≤U
ck≤ U
dc/ 2+H, U
dc/ 2-h≤U
cx≤ U
dc/ 2+h, wherein H, h are stagnant endless belt.
In order clearly to analyze the operation principle of high voltage direct current-commutator transformer, now the high-pressure side tandem type Modularized current transformer of high voltage direct current-commutator transformer to be analyzed, the high-pressure side DC bus is U
dc, the contact voltage of brachium pontis 11 is U
dc/ 2, first brachium pontis output voltage of brachium pontis 12 is U
a1, second brachium pontis output voltage is U
a2, two brachium pontis output voltages are U
ac, have following relationship to set up
U
a1+U
a2=U
dc （1.1）
U
a1-U
dc/2=U
ac (1.2)
Known according to the KVL law, also there is following voltage relationship formula
U
a1=U
dc/2-U
ac (1.3)
U
a2=U
dc/2+U
ac (1.4)
Wherein, U
ac, U
dcfor known quantity, so U
a1and U
a2just can calculate by (1.3), (1.4) formula, thereby can draw the reference voltage level of half brachium pontis half-bridge topology power model up and down, the equivalent control method of the high-pressure side tandem type Modularized current transformer of high voltage direct current-commutator transformer as shown in figure 10.
According to specific exemplary embodiment, invention has been described herein.It will be apparent carrying out to one skilled in the art suitable replacement or revise under not departing from the scope of the present invention.Exemplary embodiment is only illustrative, rather than, to the restriction of scope of the present invention, scope of the present invention has appended claim definition.
Claims (3)
1. a high voltage direct current-commutator transformer, is characterized in that: comprise the tandem type Modularized current transformer, the sinusoidal wave transformer of double winding medium and low frequency and input parallel modular current transformer;
Described tandem type Modularized current transformer comprises two brachium pontis, and wherein, upper and lower half brachium pontis of the first brachium pontis respectively contains a capacitor group, and the two is connected on the contact of the first brachium pontis; First brachium pontis of the second brachium pontis by head to tail connect successively half-bridge topology power model and 1 reactor of at least 2 forwards, and second brachium pontis by head to connect the successively half-bridge topology power model of 1 reactor and at least 2 forwards of tail, and 2 reactors in upper and lower half brachium pontis are connected on the contact of the second brachium pontis; The head end of two brachium pontis connects the high-pressure side positive pole jointly, and tail end connects the high-pressure side negative pole jointly;
The sinusoidal wave transformer of described double winding medium and low frequency comprises 1 high input voltage winding and 1 low pressure output winding, and the two ends of high input voltage winding connect respectively the contact of first and second brachium pontis;
Described input parallel modular current transformer comprises the current transformer submodule that at least one structure is identical, and the input of each current transformer submodule all is connected with the low pressure output winding of the sinusoidal wave transformer of double winding medium and low frequency, and the connected mode that the output of all current transformer submodules adopts series, parallel or connection in series-parallel to mix.
2. a kind of high voltage direct current-commutator transformer as claimed in claim 1, it is characterized in that: described half-bridge topology power model comprises two turn-off devices with anti-paralleled diode and an electric capacity, first and second turn-off device forward is connected in series, again with Capacitance parallel connection, the tie point of described first and second turn-off device is as the positive pole of half-bridge topology power model, and the negative pole of the second turn-off device is as the negative pole of half-bridge topology power model.
3. a kind of high voltage direct current-commutator transformer as claimed in claim 1 or 2, it is characterized in that: described current transformer submodule comprises passive filter module and the power conversion module that order is in series, wherein, passive filter module adopts LC filter circuit or LCL filter circuit, and the power conversion module adopts two level half-bridge topologys, two Level Full Bridge topologys, many level half-bridges topology or many Level Full Bridges topology.
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| CN2013103331798A CN103457468A (en) | 2013-08-01 | 2013-08-01 | High voltage direct current-direct current transformer |
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| CN2013103331798A CN103457468A (en) | 2013-08-01 | 2013-08-01 | High voltage direct current-direct current transformer |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105471267A (en) * | 2015-12-10 | 2016-04-06 | 西华大学 | High-voltage high-power DC-DC converter adopting modular structure |
| CN105490557A (en) * | 2015-12-16 | 2016-04-13 | 大连尚能科技发展有限公司 | Power module group for converter |
| CN106411120A (en) * | 2016-11-21 | 2017-02-15 | 华中科技大学 | Switch assembly and application and control method thereof |
| CN109980936A (en) * | 2019-03-26 | 2019-07-05 | 浙江大学 | The voltage control method of modular multilevel structure resonance converter |
| CN110855154A (en) * | 2019-11-29 | 2020-02-28 | 清华大学 | Single-phase half-bridge modular multilevel isolated DC transformer |
| CN112751496A (en) * | 2019-10-30 | 2021-05-04 | 中车株洲电力机车研究所有限公司 | Current transformer |
| CN113381607A (en) * | 2021-06-08 | 2021-09-10 | 哈尔滨工业大学 | Low-cost high-efficiency high-transformation-ratio DC/DC converter |
| CN114679073A (en) * | 2022-05-06 | 2022-06-28 | 西安交通大学 | Data center power module and modular power supply |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105471267A (en) * | 2015-12-10 | 2016-04-06 | 西华大学 | High-voltage high-power DC-DC converter adopting modular structure |
| CN105490557A (en) * | 2015-12-16 | 2016-04-13 | 大连尚能科技发展有限公司 | Power module group for converter |
| CN106411120A (en) * | 2016-11-21 | 2017-02-15 | 华中科技大学 | Switch assembly and application and control method thereof |
| CN109980936A (en) * | 2019-03-26 | 2019-07-05 | 浙江大学 | The voltage control method of modular multilevel structure resonance converter |
| CN109980936B (en) * | 2019-03-26 | 2021-03-26 | 浙江大学 | Voltage control method of modular multilevel structure resonant converter |
| CN112751496A (en) * | 2019-10-30 | 2021-05-04 | 中车株洲电力机车研究所有限公司 | Current transformer |
| CN112751496B (en) * | 2019-10-30 | 2022-08-12 | 中车株洲电力机车研究所有限公司 | Current transformer |
| CN110855154A (en) * | 2019-11-29 | 2020-02-28 | 清华大学 | Single-phase half-bridge modular multilevel isolated DC transformer |
| CN113381607A (en) * | 2021-06-08 | 2021-09-10 | 哈尔滨工业大学 | Low-cost high-efficiency high-transformation-ratio DC/DC converter |
| CN113381607B (en) * | 2021-06-08 | 2022-09-02 | 哈尔滨工业大学 | Low-cost high-efficiency high-transformation-ratio DC/DC converter |
| CN114679073A (en) * | 2022-05-06 | 2022-06-28 | 西安交通大学 | Data center power module and modular power supply |
| CN114679073B (en) * | 2022-05-06 | 2024-05-10 | 西安交通大学 | Data center power module and modularized power supply |
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Application publication date: 20131218 |