CN101645646A - Method for realizing variable voltage level constant power output of converter - Google Patents
Method for realizing variable voltage level constant power output of converter Download PDFInfo
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- CN101645646A CN101645646A CN200910011716A CN200910011716A CN101645646A CN 101645646 A CN101645646 A CN 101645646A CN 200910011716 A CN200910011716 A CN 200910011716A CN 200910011716 A CN200910011716 A CN 200910011716A CN 101645646 A CN101645646 A CN 101645646A
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Abstract
The invention relates to a method for realizing variable voltage level constant power output of a converter. The method realizes the series connection and parallel connection of variable flow chains consisting of a plurality of variable frequency power units in an A phase, a B phase and a C phase in a plurality of transformation modes of combining the series connection and the parallel connectionof a plurality of identical variable frequency power units and through the opening and closing control for a switch, and simultaneously controls the consistency of the current, the voltage amplitude,the frequency and the like output by each variable frequency power unit, thereby realizing the increase of the output current when the output voltage is decreased, and achieving the constant power output of a plurality of needed voltage levels, i.e. realizing variable multivoltage level constant power output on one converter. The converter is based on a multilevel H bridge series connection technology. The converter can be a four-quadrant converter or a two-quadrant converter or a one-quadrant converter and is depended on the circuit structures of the variable frequency power units, and a controllable rectifying device or an inverter of each variable frequency power unit can be an IGBT, an IGCT, an IEGT, or a PP IGBT.
Description
Technical field
The present invention relates to a kind of current transformer, particularly a kind of current transformer implementation method of variable voltage level constant power output.
Background technology
Along with the development of power electronic device, current transformer is widely used in telecommunications, the energy, communications and transportation, military equipment, material engineering, electric power system and electric drive field, to drive electric drive mechanism or to use as variable frequency power supply.At present, more advanced high-voltage motor RHVC adopts IGBT power unit cascade (series connection of H bridge) multilevel converter, digital control technology, SPWM pulse modulation technology, have characteristics such as energy-efficient, High Power Factor and high reliability, the energy that the conventional method that is through with causes and manpower waste, useful lifes such as motor, blower fan, water pump have been prolonged, improve production technology, improved production efficiency.
The high capacity that develops into current transformer of the multiple-level serially connected technology of H bridge has been opened up new approach, and level quantity is many more, and output waveform harmonic distortion is more little, approaches sinusoidal output more, is more suitable for big capacity, high-tension occasion.
At present, also reducing of geometric ratio of power output when converter plant reduces at output voltage, in the occasion that needs the permanent power output of multi-voltage grade, can only select a plurality of RHVC to realize, can realize that by a current transformer current transformer of the permanent power output of multi-voltage grade yet there are no report.
Summary of the invention
The current transformer implementation method that the purpose of this invention is to provide a kind of variable voltage level constant power output, this method reach the purpose of permanent power output multiple voltage grade by the series connection and the multiple variation that combines in parallel of a plurality of power cells.
For achieving the above object, the present invention is achieved through the following technical solutions:
A kind of current transformer implementation method of variable voltage level constant power output, series connection and the in parallel mapping mode that combine and to the consistency control of the electric current of each frequency conversion power unit output, voltage magnitude, frequency of this method by a plurality of identical frequency conversion power units realizes permanent power output multiple voltage grade.
When rated output voltage is full voltage, form a unsteady flow chain by n unsteady flow power unit cascade, whenever be made up of a unsteady flow chain, realize the permanent power output of three-phase alternating current, wherein n is an even number.
Rated output voltage is two of a full voltage/for the moment, be composed in series a unsteady flow chain by n/2 frequency conversion power unit, whenever is in parallel by two such unsteady flow chains, realizes the permanent power output of three-phase alternating current, and wherein n is an even number.
Rated output voltage is four of a full voltage/for the moment, be composed in series a unsteady flow chain by n/4 frequency conversion power unit, whenever is in parallel by four such unsteady flow chains, realizes the permanent power output of three-phase alternating current, and wherein n is an even number.
Rated output voltage is eight of a full voltage/for the moment, be composed in series a unsteady flow chain by n/8 frequency conversion power unit, whenever is in parallel by eight such unsteady flow chains, realizes the permanent power output of three-phase alternating current, and wherein n is an even number.
Rated output voltage is the n/for the moment of full voltage, is whenever composed in parallel by n frequency conversion power unit, realizes the permanent power output of three-phase alternating current.
With all frequency conversion power unit parallel connections, can realize the permanent power output of direct current output or single phase alternating current (A.C.).
With all frequency conversion power unit series connection, can realize the permanent power output of single phase alternating current (A.C.).
The controlled condition that this method need satisfy is:
1) series and parallel of each frequency conversion power unit is realized by branch, the combined floodgate of control respective switch, and the control principle is the electric pressure of required permanent power output;
2) each frequency conversion power unit output same-phase, the same frequency in the same unsteady flow chain, and voltage magnitude equates;
3) Bing Lian each unsteady flow chain output current equates.
Compared with prior art, novelty of the present invention and creativeness are embodied in: by the multiple variation of the series and parallel of a plurality of frequency conversion power units, realize the equal permanent power output of multiple voltage output level.
Description of drawings
Fig. 1 is the connection principle schematic diagram of current transformer;
Fig. 2 is the topological diagram of n frequency conversion power unit series connection;
Fig. 3 is that n/2 frequency conversion power unit is composed in series a unsteady flow chain, every topological diagram that is in parallel by two unsteady flow chains;
Fig. 4 is that n/4 frequency conversion power unit is composed in series a unsteady flow chain, every topological diagram that is in parallel by four unsteady flow chains;
Fig. 5 is that n/8 frequency conversion power unit is composed in series a unsteady flow chain, every topological diagram that is in parallel by eight unsteady flow chains;
Fig. 6 is every topological diagram by n frequency conversion power unit parallel connection;
Fig. 7 is every phase n frequency conversion power unit parallel connection, the more described unsteady flow of three-phase unit in parallel is carried out topological diagram in parallel again;
Fig. 8 is the topological diagram of 8 frequency conversion power unit series connection;
Fig. 9 is that 4 frequency conversion power units are composed in series a unsteady flow chain, every topological diagram that is in parallel by two unsteady flow chains;
Figure 10 is that 2 frequency conversion power units are composed in series a unsteady flow chain, every topological diagram that is in parallel by four unsteady flow chains;
Figure 11 is that 1 frequency conversion power unit is composed in series a unsteady flow chain, every topological diagram that is in parallel by eight unsteady flow chains;
Figure 12 is 8 frequency conversion power unit parallel connections of every phase, the more described unsteady flow of three-phase unit in parallel is carried out topological diagram in parallel again;
Figure 13 is n=8, and power is the current transformer schematic diagram of 5000kVA;
Figure 14-a is the circuit theory diagrams of four-quadrant frequency conversion power unit;
Figure 14-b is the circuit theory diagrams of two quadrants or single-phase limit frequency conversion power unit;
Four-quadrant type converter circuit schematic diagram when Figure 15 is 13.2kV full voltage grade;
Embodiment
A kind of current transformer implementation method of variable voltage level constant power output, this method is by the series connection and the multiple variation that combines in parallel of a plurality of identical frequency conversion power units, by divide-shut brake control to switch, realize the parallel connection of the unsteady flow chain that A, B, the every mutually a plurality of frequency conversion power units of C three-phase are formed, simultaneously by consistency control to the electric current of each frequency conversion power unit output, voltage magnitude, frequency, thereby output current increases when realizing the output voltage reduction, reaches permanent power and exports a plurality of required electric pressures.
See Fig. 2, the full voltage grade: whenever be composed in series a unsteady flow chain by n frequency conversion power unit, realize the permanent power output of full voltage three-phase alternating current, wherein n is an even number.
See Fig. 3,1/2 full voltage grade: be composed in series a unsteady flow chain by n/2 frequency conversion power unit, whenever be in parallel by two unsteady flow chains, realize the permanent power output of three-phase alternating current of 1/2 full voltage grade, wherein n is an even number.
See Fig. 4,1/4 full voltage grade: be composed in series a unsteady flow chain by n/4 frequency conversion power unit, whenever be in parallel by four unsteady flow chains, realize the permanent power output of three-phase alternating current of 1/4 full voltage grade, wherein n is an even number.
See Fig. 5,1/8 full voltage grade: be composed in series a unsteady flow chain by n/8 frequency conversion power unit, whenever be in parallel by eight unsteady flow chains, realize the permanent power output of three-phase alternating current of 1/8 full voltage grade, wherein n is an even number.
See Fig. 6,1/n full voltage grade:, realize the permanent power output of three-phase alternating current of 1/n full voltage grade by n frequency conversion power unit parallel connection.
See Fig. 7, the permanent power output of direct current or single phase alternating current (A.C.): as with every phase n frequency conversion power unit parallel connection, the more described unsteady flow of three-phase unit in parallel is carried out parallel connection again, can realize the permanent power output of direct current output or single phase alternating current (A.C.).
The controlled condition that this method need satisfy is:
1) series and parallel of each frequency conversion power unit is realized by branch, the combined floodgate of control respective switch, and the control principle is the electric pressure of required permanent power output;
2) each frequency conversion power unit output same-phase, the same frequency in the same unsteady flow chain, and voltage magnitude equates;
3) Bing Lian each unsteady flow chain output current equates.
Embodiment 1:n=8, power are 5000kVA.
See Fig. 8, full voltage grade 13.2kV: whenever be composed in series a unsteady flow chain, realize the permanent power 5000kVA output of full voltage 13.2kV three-phase alternating current by 8 frequency conversion power units.
See Fig. 9,1/2 full voltage class 6 .6kV: be composed in series a unsteady flow chain by 4 frequency conversion power units, whenever be in parallel, realize the permanent power 5000kVA output of three-phase alternating current of 6.6kV grade by two unsteady flow chains.
See Figure 10,1/4 full voltage grade 3.3kV: be composed in series a unsteady flow chain by 2 frequency conversion power units, whenever be in parallel, realize the permanent power 5000kVA output of three-phase alternating current of 3.3kV grade by four unsteady flow chains.
See Figure 11,1/8 full voltage grade 1.65kV: form a unsteady flow chain by 1 frequency conversion power unit, whenever be in parallel, realize the permanent power 5000kVA output of three-phase alternating current of 1.65kV electric pressure by eight unsteady flow chains.
See Figure 12, the permanent power output of direct current 0-1000V or single phase alternating current (A.C.): as with 8 frequency conversion power unit parallel connections of every phase, the more described unsteady flow of three-phase unit in parallel is carried out parallel connection again, can realize the permanent power 5000kVA output of direct current output 0-1000V.
See Figure 13, the concrete schematic diagram of current transformer; For n=8, power are the current transformer of 5000kVA.
This current transformer is based on many level H-bridges serial connection technology, and the highest output 13.2kV need not step-up transformer, capacity 5000kVA.
The three-phase alternating current of being sent here by electrical network inserts the rectification phase shifting transformer, the secondary of rectification phase shifting transformer has 24 three phase windings to give 24 frequency conversion power unit U1-U8 respectively, V1-V8, the W1-W8 power supply, every single-phase output head and the tail series connection by 8 frequency conversion power units, and the output voltage of each frequency conversion power unit can be controlled in 0～950V scope, after the PWM ripple phase shift stack of each frequency conversion power unit output, form the phase voltage of 7.6kV, A, B, the C three-phase adopts Y shape to connect, formed that motor is supplied with in high-quality sinewave output (frequency can be set at 0-120Hz, and voltage is at 0-13.2kV) that line voltage is up to 13.2kV or as variable frequency power supply.
The concrete principle of each frequency conversion power unit among Figure 13 is seen Figure 14, when frequency conversion power unit is exactly a four quadrant convertor when being Figure 14-a, when frequency conversion power unit is exactly two quadrants or one quadrant convertor when being Figure 14-b.
Among Figure 14-a, the basic topological structure of this frequency conversion power unit is the voltage-source type frequency converter of AC-DC-AC type three-phase controlled rectification/single-phase inversion output, and the rectification side is the three-phase controlled rectification bridge, and the three-phase alternating current of importing is rectified into direct current; The inversion side is a single-phase inversion, realizes single-phase controlled interchange 0～950V output.This frequency conversion power unit can be realized the two-way flow of energy, electric current can be from electrical network through intermediate dc electric capacity flow direction motor, also can because of motor braking or machine operation when the generating operation mode, electric current flows to electrical network from motor through the electric capacity of DC link, realizes four quadrant running control.Wherein controlled rectification device and inversion device can be IGBT or IGCT or IEGT or PP IGBT.
Among Figure 14-b, the basic topological structure of this frequency conversion power unit is the voltage-source type frequency converter of the uncontrollable rectification of AC-DC-AC type three-phase diode/single-phase inversion output, and promptly this converter unit is the three-phase alternating current input, single-phasely is output as controlled interchange 0-950V.Wherein the inversion device can be IGBT or IGCT or IEGT.
Each frequency conversion power unit is full ripe technology, and the output voltage of frequency conversion power unit and series connection quantity have determined the maximum output voltage of this current transformer, and the rated current of each frequency conversion power unit determines the output current of this current transformer.
A winding of rectification phase shifting transformer is the Y type, and each secondary winding is for prolonging limit △ type, and the primary voltage of transformer is according to the voltage design of using electrical network.
Divide-shut brake control by to each switch realizes A, B, the parallel connection of converter unit separately of the every phase of C three-phase, and obtains the output of different electric pressures.Realized that the power output under the different electric pressures remains 5000kVA.
Ac output end, each 1 group of dc output end.
Opening and closing state, the control mode of fan-out capability, switch see Table 1.
See Figure 15: four-quadrant type converter circuit schematic diagram during full voltage 13.2kV grade.When frequency conversion power unit was Figure 14-a, 8 frequency conversion power units series connection of every phase realized the permanent power 5000kVA output of full voltage 13.2kV three-phase alternating current.
Table 1
Claims (7)
1, a kind of current transformer implementation method of variable voltage level constant power output, it is characterized in that, series connection and the in parallel mapping mode that combine and to the consistency control of the electric current of each frequency conversion power unit output, voltage magnitude, frequency of this method by a plurality of identical frequency conversion power units realizes permanent power output multiple voltage grade.
2, the current transformer implementation method of a kind of variable voltage level constant power output according to claim 1, it is characterized in that, when rated output voltage is full voltage, form a unsteady flow chain by n unsteady flow power unit cascade, whenever, form by a unsteady flow chain, realize the permanent power output of three-phase alternating current, wherein n is an even number.
3, the current transformer implementation method of a kind of variable voltage level constant power output according to claim 1, it is characterized in that, rated output voltage is two of a full voltage/for the moment, be composed in series a unsteady flow chain by n/2 frequency conversion power unit, whenever, be in parallel by two such unsteady flow chains, realize the permanent power output of three-phase alternating current, wherein n is an even number.
4, the current transformer implementation method of a kind of variable voltage level constant power output according to claim 1, it is characterized in that, rated output voltage is four of a full voltage/for the moment, be composed in series a unsteady flow chain by n/4 frequency conversion power unit, whenever, be in parallel by four such unsteady flow chains, realize the permanent power output of three-phase alternating current, wherein n is an even number.
5, the current transformer implementation method of a kind of variable voltage level constant power output according to claim 1, it is characterized in that, rated output voltage is eight of a full voltage/for the moment, be composed in series a unsteady flow chain by n/8 frequency conversion power unit, whenever, be in parallel by eight such unsteady flow chains, realize the permanent power output of three-phase alternating current, wherein n is an even number.
6, the current transformer implementation method of a kind of variable voltage level constant power output according to claim 1, it is characterized in that, rated output voltage is the n/for the moment of full voltage, is whenever composed in parallel by n frequency conversion power unit, realizes the permanent power output of three-phase alternating current.
7, the current transformer implementation method of a kind of variable voltage level constant power output according to claim 1 is characterized in that, with all frequency conversion power unit parallel connections, can realize the permanent power output of direct current output or single phase alternating current (A.C.).
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101777842A (en) * | 2010-03-24 | 2010-07-14 | 上海交通大学 | Medium voltage frequency conversion power circuit system |
| CN102882416A (en) * | 2012-10-19 | 2013-01-16 | 株洲变流技术国家工程研究中心有限公司 | High-voltage frequency converter topology circuit and basic converter chain circuit |
| CN102931854A (en) * | 2012-10-25 | 2013-02-13 | 株洲变流技术国家工程研究中心有限公司 | Cascaded high-voltage inverter |
| CN103023345A (en) * | 2012-10-24 | 2013-04-03 | 株洲变流技术国家工程研究中心有限公司 | Multivoltage level output variable-frequency power source and control method thereof |
| CN103151947A (en) * | 2012-10-25 | 2013-06-12 | 株洲变流技术国家工程研究中心有限公司 | Cascaded high voltage frequency converter controlling method |
| CN103875147A (en) * | 2011-10-14 | 2014-06-18 | Abb技术有限公司 | A multilevel converter and a method for controlling multilevel converter including balancing cell voltages |
| CN105207607A (en) * | 2015-09-21 | 2015-12-30 | 北京科诺伟业科技股份有限公司 | Three-phase ABC alternating-current tandem type photovoltaic array |
| CN107086805A (en) * | 2016-06-07 | 2017-08-22 | 维尔纳（福建）电机有限公司 | A kind of reconstitutable single-phase digital frequency conversion generator |
| CN109245733A (en) * | 2018-09-04 | 2019-01-18 | 中国商用飞机有限责任公司北京民用飞机技术研究中心 | A kind of linear power amplifier of multivoltage output |
| CN110716129A (en) * | 2019-11-12 | 2020-01-21 | 上海辛格林纳新时达电机有限公司 | High-voltage power unit test system |
| CN116068361A (en) * | 2023-04-04 | 2023-05-05 | 常州博瑞电力自动化设备有限公司 | Alternating current test system |
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2009
- 2009-05-27 CN CN200910011716A patent/CN101645646A/en active Pending
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101777842A (en) * | 2010-03-24 | 2010-07-14 | 上海交通大学 | Medium voltage frequency conversion power circuit system |
| CN103875147B (en) * | 2011-10-14 | 2017-08-25 | Abb技术有限公司 | Multi-level converter and for control include balancing cell voltages multi-level converter method |
| CN103875147A (en) * | 2011-10-14 | 2014-06-18 | Abb技术有限公司 | A multilevel converter and a method for controlling multilevel converter including balancing cell voltages |
| CN102882416B (en) * | 2012-10-19 | 2016-02-10 | 株洲变流技术国家工程研究中心有限公司 | A kind of high voltage converter topological circuit and basic unsteady flow chain circuit |
| CN102882416A (en) * | 2012-10-19 | 2013-01-16 | 株洲变流技术国家工程研究中心有限公司 | High-voltage frequency converter topology circuit and basic converter chain circuit |
| CN103023345A (en) * | 2012-10-24 | 2013-04-03 | 株洲变流技术国家工程研究中心有限公司 | Multivoltage level output variable-frequency power source and control method thereof |
| CN103023345B (en) * | 2012-10-24 | 2015-08-05 | 株洲变流技术国家工程研究中心有限公司 | A kind of multi-voltage grade exports variable frequency power supply and control method thereof |
| CN103151947A (en) * | 2012-10-25 | 2013-06-12 | 株洲变流技术国家工程研究中心有限公司 | Cascaded high voltage frequency converter controlling method |
| CN102931854A (en) * | 2012-10-25 | 2013-02-13 | 株洲变流技术国家工程研究中心有限公司 | Cascaded high-voltage inverter |
| CN105207607A (en) * | 2015-09-21 | 2015-12-30 | 北京科诺伟业科技股份有限公司 | Three-phase ABC alternating-current tandem type photovoltaic array |
| CN107086805A (en) * | 2016-06-07 | 2017-08-22 | 维尔纳（福建）电机有限公司 | A kind of reconstitutable single-phase digital frequency conversion generator |
| CN107086805B (en) * | 2016-06-07 | 2024-03-29 | 维尔纳集电电子科技(福建)有限公司 | Recombinant single-phase digital variable frequency generator |
| CN109245733A (en) * | 2018-09-04 | 2019-01-18 | 中国商用飞机有限责任公司北京民用飞机技术研究中心 | A kind of linear power amplifier of multivoltage output |
| CN110716129A (en) * | 2019-11-12 | 2020-01-21 | 上海辛格林纳新时达电机有限公司 | High-voltage power unit test system |
| CN116068361A (en) * | 2023-04-04 | 2023-05-05 | 常州博瑞电力自动化设备有限公司 | Alternating current test system |
| CN116068361B (en) * | 2023-04-04 | 2023-07-11 | 常州博瑞电力自动化设备有限公司 | Alternating current test system |
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