CN105226957A - A kind of three-phase-single-phase potential device of no industrial frequency transformer - Google Patents
A kind of three-phase-single-phase potential device of no industrial frequency transformer Download PDFInfo
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Abstract
The invention discloses a kind of three-phase-single-phase potential device of no industrial frequency transformer, this device adopts single-phase-single-phase invertor multi-module cascade structure to bear three phase network high pressure, after three-phase cascade, series connection exports and cancels Industrial Frequency Transformer, directly be connected with single-phase power supply network, improve output voltage grade.Described single-phase-single-phase invertor forms primarily of rectification circuit, bidirectional DC-DC converter circuit and inverter circuit.The present invention is single-phase-and single-phase invertor is simple for structure, can the structure of mitigation system greatly, achieve the two-way flow of three phase network to single phase power supply net power, improve energy transmission efficiency, therefore, three phase network can not be caused uneven.In addition, by selecting suitable control strategy, converter has idle and harmonic compensation function, can improve three phase network side the quality of power supply and for single phase power supply net compensating reactive power and harmonic wave.
Description
Technical field
The present invention relates to a kind of three-phase-Monophase electric power electronic transformer apparatus, particularly electrical network three-phase electricity is being converted to the application in required single-phase electricity.
Background technology
At present, a large amount of single-phase loads is there is at many industrial circles, and single-phase load generally has heavy duty, low power factor, the feature of higher harmonics, thus cause electrical network asymmetric operation, affect electric network reliability, reduce power supply quality, increase loss, these single-phase loads comprise electrified railway traction power supply system and induction heating, petrochemical industry is powered, in order to meet this load needs, the potential device that normal use three phase transformation is single-phase, comprising Scott Transformer, its schematic diagram as shown in Figure 1, but Scott Transformer is only when two-phase lateral load balances, the electric current of three-phase side could realize, and former limit earthing potential produces drift with load variations, zero-sequence current is also had to flow through electrical network time serious, electric power system zero-sequence current protective relaying maloperation may be caused to do, cause each phase winding voltage of transformer uneven simultaneously, and increase the weight of the insulation burden of winding.
In order to effectively solve the problem, propose a kind of power electronics potential device based on converter, this convertor controls degree of freedom is large, and output voltage is adjustable; Not by the restriction of load; Input current waveform is sinusoidal, to electrical network no-harmonic wave pollution; The features such as energy capable of bidirectional flowing.
But owing to being subject to the restriction of power electronic device development level, the converter that only voucher is individual in many practical applications also cannot directly be connected with three phase network, thus needs triphase step-down transformer and single-phase step-up transformer.The existence of transformer makes power electronic equipment system require higher to the corresponding corollary equipment such as converter, wire, and equipment and line loss also become large, also more complicated thereupon, and volume and weight is difficult to reduce.
Summary of the invention
In view of the deficiencies in the prior art, object of the present invention is just to provide a kind of three-phase-single-phase potential device of no industrial frequency transformer, this device can both can absorb from three phase network and provide power to single-phase electrical network under the condition of no industrial frequency transformer, also can absorb from single-phase electrical network and to three phase network feedback power, realize the conversion of three-phase electricity to single-phase electricity, and this apparatus structure be simple, cost is low, volume is little, and it uses, easy to maintenance.
The present invention solves its technical problem, and the technical scheme adopted is:
1, a kind of three-phase-single-phase potential device of no industrial frequency transformer, each phase (A of three phase network, B, C) through reactor (LA, LB, LC) the individual converter (A1 ~ An of cascade n (n>1) again, B1 ~ Bn, C1 ~ Cn) pick out, wherein the output of the positive port a1P of A phase first converter is connected on B phase n-th converter negative terminal mouth bnN, the output of the positive port b1P of same B phase first converter is connected on C phase n-th converter negative terminal mouth cnN, first converter positive port c1P of last C phase is connected to single-phase electrical network through reactor, form single-phase power supply network.It is characterized in that:
A, A phase branch road first positive port A1P of converter A1 grid side is connected with three phase network A phase through reactor LA, the grid side negative terminal mouth A1N of A1 is connected with the positive port A2P of the grid side of second converter ... grid side negative terminal mouth A (n-1) N of (n-1)th converter A (n-1) is connected with the positive port AnP of the grid side of the n-th converter An, and B, C phase branch road connects identical with A phase; The grid side negative terminal mouth AnN of each phase (A, B, C) n-th converter, BnN, CnN are connected to O point jointly.
The inverter side negative terminal mouth a1N of b, A phase branch road first converter A1 is connected with the positive port a2P of the inverter side of second converter A2 ... inverter side negative terminal mouth a (n-1) N of (n-1)th converter A (n-1) is connected with the positive port anP of the inverter side of the n-th converter An, and B, C phase branch road connects identical with A phase; The output of the positive port a1P of A phase first converter inverter side is connected on B phase n-th converter inverter side negative terminal mouth bnN, the output of the positive port b1P of same B phase first converter inverter side is connected on C phase n-th converter inverter side negative terminal mouth cnN, and the positive port c1P of last C phase first converter inverter side is connected to single-phase power supply network through reactor.The inverter side negative terminal mouth anN of the n-th converter of A phase is connected to the negative terminal N point of single-phase electrical network.
2, realize of the present invention single single-phase-single-phase invertor block diagram as shown in Figure 3, this converter primarily of rectification circuit, bidirectional DC-DC converter circuit and inverter circuit composition, each single-phase-single-phase invertor is the module of apparatus of the present invention.Realize converter scheme of the present invention and have following basic structure: Fig. 4 for can realize of the present invention based on two level H-bridges single-phase-single-phase invertor structure chart, Fig. 5 for can realize of the present invention based on two level half-bridges single-phase-single-phase invertor structure chart, Fig. 6 for can realize of the present invention based on three level H bridge single-phase-single-phase invertor structure chart, Fig. 7 for can realize of the present invention based on tri-level half-bridge single-phase-single-phase invertor structure chart.All contain rectification circuit, bidirectional DC-DC converter circuit and inverter circuit in above-described converter, the electronic power switch device in converter all adopts PWM control mode.Wherein the basic function of rectification circuit is the control by switch tube, carries out rectification, realize output dc voltage adjustable to the alternating voltage of three phase network; In bidirectional DC-DC converter, transformer primary side brachium pontis realizes invert function, and direct voltage is reverse into alternating voltage supply transformer, Circuit Fault on Secondary Transformer brachium pontis realizes rectification function, and the alternating current that transformer exports is become direct current; Inverter circuit major function is, by the control of switch tube, the output DC inversion of bidirectional DC-DC converter is become specific alternating current.Each phase multiple single-phase-single-phase invertor rectification side and inverter side respectively cascade obtain the input and output of voltage levels.It should be noted that, rectification circuit in converter, bidirectional DC-DC converter circuit and inverter circuit can be the combinations of three level, two level or even many level and half-bridge, full-bridge, resonant network or resonance free network can also be had in addition in bidirectional DC-DC converter circuit, wherein resonant network is for two level H-bridge resonance bidirectional DC-DC converter circuit, as shown in Figure 8.In figure, Smn represents the switching device of the n-th numbering of m brachium pontis, C1 ... Cn represents DC capacitor.
Compared with prior art, beneficial effect of the present invention is:
1, the three-phase-single-phase potential device of the no industrial frequency transformer of the present invention's proposition can cancel the Industrial Frequency Transformer of input, output, owing to adopting medium/high frequency transformer (MFT) in bidirectional DC-DC converter circuit, relative to traditional Industrial Frequency Transformer system, can the volume of mitigation system greatly, increase work efficiency, and system controlled, not easily causes the adverse consequencess such as resonance.
2, every phase single-phase-single-phase invertor cascade is connected outputs again, and improve output voltage grade, in real work, the power of every circuitry phase can both control to make it to balance, thus can ensure the balance of three phase network.
3, because the output voltage phase place of single-phase inverter, frequency and amplitude are completely controlled, voltage-phase, frequency and the amplitude that therefore can export according to the information of voltage adjustment inverter of supply network, make it to meet user's requirement, improve the quality of power supply, and energy can two-way flow between three phase network and single phase power supply net.
Accompanying drawing explanation
Fig. 1 is traditional Scott Transformer schematic diagram;
Fig. 2 is the three-phase-single-phase potential device structure chart of cascade connection type no industrial frequency transformer of the present invention;
Fig. 3 be single single-phase-single-phase PWM transformer configuration figure;
Fig. 4 be the present invention is based on two level H-bridge structures single-phase-single-phase PWM converter;
Fig. 5 be the present invention is based on two level half-bridge structures single-phase-single-phase PWM converter;
Fig. 6 be the present invention is based on three level diode clamp H bridge construction single-phase-single-phase PWM converter;
Fig. 7 be the present invention is based on three level diode clamp half-bridge structure single-phase-single-phase PWM converter;
Fig. 8 is the resonance bidirectional DC-DC converter circuit that the present invention is based on two level H-bridge structures.
Embodiment
Shown in Fig. 2, a kind of embodiment of the present invention is: a kind of three-phase-single-phase potential device of no industrial frequency transformer, each phase (A of three phase network, B, C) through reactor (LA, LB, LC) the individual converter (A1 ~ An of cascade n (n>1) again, B1 ~ Bn, C1 ~ Cn) pick out, wherein the output of the positive port a1P of A phase first converter is connected on B phase n-th converter negative terminal mouth bnN, the output of the positive port b1P of same B phase first converter is connected on C phase n-th converter negative terminal mouth cnN, first converter positive port c1P of last C phase is connected to single-phase electrical network through reactor, form single-phase power supply network.Wherein:
A, A phase branch road first positive port A1P of converter A1 grid side is connected with three phase network A phase through reactor LA, the grid side negative terminal mouth A1N of A1 is connected with the positive port A2P of the grid side of second converter ... grid side negative terminal mouth A (n-1) N of (n-1)th converter A (n-1) is connected with the positive port AnP of the grid side of the n-th converter An, and B, C phase branch road connects identical with A phase.The grid side negative terminal mouth AnN of each phase (A, B, C) n-th converter, BnN, CnN are connected to O point jointly.
The inverter side negative terminal mouth a1N of b, A phase branch road first converter A1 is connected with the positive port a2P of the inverter side of second converter A2 ... inverter side negative terminal mouth a (n-1) N of (n-1)th converter A (n-1) is connected with the positive port anP of the inverter side of the n-th converter An, and B, C phase branch road connects identical with A phase.The output of the positive port a1P of A phase first converter inverter side is connected on B phase n-th converter inverter side negative terminal mouth bnN, the output of the positive port b1P of same B phase first converter inverter side is connected on C phase n-th converter inverter side negative terminal mouth cnN, and the positive port c1P of last C phase first converter inverter side is connected to single-phase power supply network through reactor.The inverter side negative terminal mouth anN of the n-th converter of A phase is connected to the negative terminal N point of single-phase electrical network.
2, the above three-phase-single-phase potential device is the three phase network based on star connection, but only need make part amendment, and the three phase network of delta connection can use equally.The converter that this device uses forms primarily of rectification circuit, bidirectional DC-DC converter circuit and inverter circuit.From modulation level angle, circuit can be two, three-level structure, and also can be many level block, from bridge arrangement angle, circuit can be full-bridge, half-bridge structure.It should be noted that, rectification circuit in converter, bidirectional DC-DC converter circuit and inverter circuit can be the combinations of three level, two level or even many level and half-bridge, full-bridge, can also have resonant network or resonance free network in addition in bidirectional DC-DC converter circuit.
Three-phase-single-phase the potential device of a kind of no industrial frequency transformer that the present invention proposes, this device adopts single-phase-single-phase invertor multi-module cascade structure to bear three phase network high pressure, after three-phase cascade, series connection exports and cancels Industrial Frequency Transformer, directly be connected with single-phase power supply network, improve output voltage grade.Described single-phase-single-phase invertor forms primarily of rectification circuit, bidirectional DC-DC converter circuit and inverter circuit.The present invention is single-phase-and single-phase invertor is simple for structure, can the structure of mitigation system greatly, achieve the two-way flow of three phase network to single phase power supply net power, improve energy transmission efficiency, therefore, three phase network can not be caused uneven.In addition, by selecting suitable control strategy, converter has idle and harmonic compensation function, can improve three phase network side the quality of power supply and for single phase power supply net compensating reactive power and harmonic wave.
Obviously, although the above three-phase-single-phase potential device is the three phase network based on star connection, only need make part amendment, the three phase network of diabolo connection can use equally.
Claims (4)
1. three-phase-single-phase the potential device of a no industrial frequency transformer, each phase (A of three phase network, B, C) through reactor (LA, LB, LC) the individual converter (A1 ~ An of cascade n (n>1) again, B1 ~ Bn, C1 ~ Cn) pick out, wherein the output of the positive port a1P of A phase first converter is connected on B phase n-th converter negative terminal mouth bnN, the output of the positive port b1P of same B phase first converter is connected on C phase n-th converter negative terminal mouth cnN, first converter positive port c1P of last C phase is connected to single-phase electrical network through reactor, form single-phase power supply network, it is characterized in that:
A, A phase branch road first positive port A1P of converter A1 grid side is connected with three phase network A phase through reactor LA, the grid side negative terminal mouth A1N of A1 is connected with the positive port A2P of the grid side of second converter ... grid side negative terminal mouth A (n-1) N of (n-1)th converter A (n-1) is connected with the positive port AnP of the grid side of the n-th converter An, and B, C phase branch road connects identical with A phase.The grid side negative terminal mouth AnN of each phase (A, B, C) n-th converter, BnN, CnN are connected to O point jointly;
The inverter side negative terminal mouth a1N of b, A phase branch road first converter A1 is connected with the positive port a2P of the inverter side of second converter A2 ... inverter side negative terminal mouth a (n-1) N of (n-1)th converter A (n-1) is connected with the positive port anP of the inverter side of the n-th converter An, and B, C phase branch road connects identical with A phase.The output of the positive port a1P of A phase first converter inverter side is connected on B phase n-th converter inverter side negative terminal mouth bnN, the output of the positive port b1P of same B phase first converter inverter side is connected on C phase n-th converter inverter side negative terminal mouth cnN, and the positive port c1P of last C phase first converter inverter side is connected to single-phase power supply network through reactor.The inverter side negative terminal mouth anN of the n-th converter of A phase is connected to the negative terminal N point of single-phase electrical network.
2. three-phase-single-phase the potential device of no industrial frequency transformer according to claim 1, it is characterized in that, described converter be primarily of rectification circuit, bidirectional DC-DC converter circuit and inverter circuit order composition single-phase-single-phase invertor, its electronic power switch device all adopts PWM control mode.
3. three-phase-single-phase the potential device of no industrial frequency transformer according to claim 2, it is characterized in that, described single-phase-single-phase invertor adopts and includes but not limited to as Types Below: based on two level H-bridge structures single-phase-single-phase PWM converter, two level half-bridges are single-phase-single-phase invertor, three level H bridge be single-phase-single-phase invertor.
4. three-phase-single-phase the potential device of no industrial frequency transformer according to claim 2, is characterized in that, described bidirectional DC-DC converter circuit can adopt the two level H-bridge resonance bidirectional DC-DC converter circuit comprising resonant network.
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Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
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CN106230295A (en) * | 2016-07-27 | 2016-12-14 | 西南交通大学 | A kind of bullet train no industrial frequency transformer auxiliary converter system |
CN106505866A (en) * | 2016-12-02 | 2017-03-15 | 中国船舶重工集团公司第七〇九研究所 | A kind of three Level Full Bridge DC converters |
CN107104443A (en) * | 2017-06-21 | 2017-08-29 | 西南交通大学 | A kind of electric power electric transformer |
CN107634655A (en) * | 2017-08-07 | 2018-01-26 | 北京交通大学 | A kind of Novel DC electric power electric transformer topology that removing solid capacity is autotomyed with failure |
CN109861551A (en) * | 2018-12-06 | 2019-06-07 | 国电南瑞科技股份有限公司 | A kind of rail traffic direct hanging type modularization three-phase turns single phase power supply system |
CN110048613A (en) * | 2019-05-31 | 2019-07-23 | 芜湖康爱而电气有限公司 | A kind of three level DCDC translation circuit of bi-directional half bridge |
CN111245254A (en) * | 2020-01-15 | 2020-06-05 | 清华大学 | Single-phase direct current port interconnected cascade multilevel converter |
CN111342680A (en) * | 2020-03-09 | 2020-06-26 | 西南交通大学 | Power electronic transformer applied to through power supply |
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1319937A (en) * | 2001-02-08 | 2001-10-31 | 张东胜 | Wave shape changing device and method |
CN102097966A (en) * | 2011-02-14 | 2011-06-15 | 东南大学 | Cascade megawatt photovoltaic grid-connected inverter |
CN103066587A (en) * | 2012-12-13 | 2013-04-24 | 国网智能电网研究院 | Optimal configuration method of modular multi-level flexible direct current system |
CN104786872A (en) * | 2015-04-16 | 2015-07-22 | 西南交通大学 | Cut-through type cophase power supply system for cascaded input-free and output-free transformers |
CN205051584U (en) * | 2015-10-08 | 2016-02-24 | 西南交通大学 | Three -phase - single -phase potential device of no frequency transformer |
-
2015
- 2015-10-08 CN CN201510646749.8A patent/CN105226957A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1319937A (en) * | 2001-02-08 | 2001-10-31 | 张东胜 | Wave shape changing device and method |
CN102097966A (en) * | 2011-02-14 | 2011-06-15 | 东南大学 | Cascade megawatt photovoltaic grid-connected inverter |
CN103066587A (en) * | 2012-12-13 | 2013-04-24 | 国网智能电网研究院 | Optimal configuration method of modular multi-level flexible direct current system |
CN104786872A (en) * | 2015-04-16 | 2015-07-22 | 西南交通大学 | Cut-through type cophase power supply system for cascaded input-free and output-free transformers |
CN205051584U (en) * | 2015-10-08 | 2016-02-24 | 西南交通大学 | Three -phase - single -phase potential device of no frequency transformer |
Cited By (13)
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CN106230295A (en) * | 2016-07-27 | 2016-12-14 | 西南交通大学 | A kind of bullet train no industrial frequency transformer auxiliary converter system |
CN106505866A (en) * | 2016-12-02 | 2017-03-15 | 中国船舶重工集团公司第七〇九研究所 | A kind of three Level Full Bridge DC converters |
CN106505866B (en) * | 2016-12-02 | 2018-08-14 | 中国船舶重工集团公司第七一九研究所 | A kind of three Level Full Bridge DC converters |
CN107104443A (en) * | 2017-06-21 | 2017-08-29 | 西南交通大学 | A kind of electric power electric transformer |
CN107634655B (en) * | 2017-08-07 | 2019-12-31 | 北京交通大学 | Direct current power electronic transformer topology with fault self-cutting capability |
CN107634655A (en) * | 2017-08-07 | 2018-01-26 | 北京交通大学 | A kind of Novel DC electric power electric transformer topology that removing solid capacity is autotomyed with failure |
CN109861551A (en) * | 2018-12-06 | 2019-06-07 | 国电南瑞科技股份有限公司 | A kind of rail traffic direct hanging type modularization three-phase turns single phase power supply system |
CN110048613A (en) * | 2019-05-31 | 2019-07-23 | 芜湖康爱而电气有限公司 | A kind of three level DCDC translation circuit of bi-directional half bridge |
CN112217406A (en) * | 2019-07-11 | 2021-01-12 | 台达电子工业股份有限公司 | Power supply device applied to solid-state transformer framework and three-phase power supply system |
US11515800B2 (en) * | 2019-07-11 | 2022-11-29 | Delta Electronics, Inc. | Power apparatus applied in SST structure and three-phase power source system having the same |
CN111245254A (en) * | 2020-01-15 | 2020-06-05 | 清华大学 | Single-phase direct current port interconnected cascade multilevel converter |
CN111342680A (en) * | 2020-03-09 | 2020-06-26 | 西南交通大学 | Power electronic transformer applied to through power supply |
CN111342680B (en) * | 2020-03-09 | 2021-11-02 | 西南交通大学 | Power electronic transformer applied to through power supply |
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