CN202586797U - Five-level variable-current topological structure with bidirectional power switches and application thereof - Google Patents
Five-level variable-current topological structure with bidirectional power switches and application thereof Download PDFInfo
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- CN202586797U CN202586797U CN 201220229380 CN201220229380U CN202586797U CN 202586797 U CN202586797 U CN 202586797U CN 201220229380 CN201220229380 CN 201220229380 CN 201220229380 U CN201220229380 U CN 201220229380U CN 202586797 U CN202586797 U CN 202586797U
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Abstract
The utility model discloses a five-level variable-current topological structure with bidirectional power switches. The five-level variable-current topological structure comprises a capacitor link and a variable current unit, wherein the capacitor link is composes of four capacitors connected in series; the variable current unit is composed of two bidirectional power switches, two diodes and four switch tubes with antiparallel diodes. The utility model further discloses a three-phase five-level current transformer. According to the utility model, by means of using the bidirectional power switches to carry out independent control on positive and negative current paths, not only can bidirectional flow of current on the bidirectional power switches be controlled, but also multi-level output of a circuit is ensured; and on the basis of outputting five levels, the number of power devices and the number of direct-current voltage sources are reduced greatly, the voltage stress of the bidirectional power switches is only 1/4 the voltage of a bus, and the topological structure is symmetrical and convenient for modular production.
Description
Technical field
The utility model belongs to electric power Semiconductor Converting Technology field, is specifically related to a kind of five level unsteady flow topological structure and application thereof with two-way power switch.
Background technology
In recent years, shortage of energy sources and environmental pollution have become the focus of world attention, and the policy of " energy-saving and emission-reduction " of advocating energetically in country is advocated down, and the economize on electricity under the mesohigh large-power occasions subtracts can be very urgent especially.China's existing mesohigh high power AC motor is direct startup mostly; Take valve regulated or fluid power coupled modes to carry out speed governing, this mode of speed regulation makes waste of energy huge, along with the fast development of China's electric utility; The demand of industrial quarters centering high-power current transformer is increasing; When these high power motors adopted frequency control, fractional energy savings can reach 10% ~ 70%, on average about 30%.Since the high-voltage and high-power power electronic device cost an arm and a leg with and restraining factors in many ways such as key technology, adopting multilevel converter is the important directions that realizes the mesohigh high-power converter.Compare with traditional current transformer, many level current transformers can use withstand voltage lower device to realize higher voltage output; Harmonic wave of output voltage content is little, in the new forms of energy occasion of generating electricity by way of merging two or more grid systems, with the quality of power supply that improves output greatly; Drag in the field at motor, the increase of current transformer output level number can make output dv/dt reduce, and has reduced the infringement of electromagnetic interference and electrical machine insulation.
In five common level unsteady flow topological structures, conventional diode clamped five-level unsteady flow topology is as shown in Figure 1; 8 of the required full-control type power devices of its single brachium pontis, 12 of clamping diodes, 4 electric capacity of DC side series connection.And along with the increase of output level number, the quantity of clamping diode and active power device will increase greatly.The cost of this topological structure is high, and complex structural designs is unfavorable for actual industrial applications.
At the many level current transformers of a kind of very widely units in series H bridge of industrial applications; As shown in Figure 2; Its each H bridge power unit all needs independently voltage fed; Adopt 8 of the required full-control type power devices of three-phase five its single brachium pontis of level cascaded H bridge current transformer of this topological structure, two direct voltage sources independently, whole three-phase current transformer need independently direct voltage source of 24 of full-control type power devices and six.Along with the raising of output voltage grade, the H bridge power unit number of series connection is with independently the direct voltage source number is also more and more, and the needed like this phase shifting transformer secondary number of windings also need roll up.Brought the volume of phase shift isolating transformer to increase, manufacture difficulty increases, problems such as cost increase thereupon.
Summary of the invention
To the above-mentioned technological deficiency of existing in prior technology, the utility model provides a kind of five level unsteady flow topological structure and application thereof with two-way power switch, has significantly reduced the quantity of power device and direct voltage source.
A kind of five level unsteady flow topological structures with two-way power switch comprise a capacitance link and a current transforming unit;
Described capacitance link is made up of four electric capacity; Wherein, capacitor C
1An end link to each other capacitor C with the positive pole of outside direct voltage source
1The other end and capacitor C
2An end link to each other capacitor C
2The other end and capacitor C
3An end link to each other capacitor C
3The other end and capacitor C
4An end link to each other capacitor C
4The other end link to each other with the negative pole of outside direct voltage source;
Described current transforming unit is made up of two two-way power switch, two diodes and four band switching tubes anti-and diode; Wherein, the anti-also switching tube S of diode of band
1Input and capacitor C
1An end link to each other the switching tube S of the anti-and diode of band
1The switching tube S of output and diode anti-with band
2Input, two-way power switch Q
1An end and diode D
1Negative electrode link to each other two-way power switch Q
1The other end and capacitor C
2An end link to each other the switching tube S of the anti-and diode of band
2The switching tube S of output and diode anti-with band
3Input link to each other and be level output end, band is the switching tube S of diode also instead
3The switching tube S of output and diode anti-with band
4Input, two-way power switch Q
2An end and diode D
2Anode link to each other two-way power switch Q
2The other end and capacitor C
4An end link to each other the switching tube S of the anti-and diode of band
4Output and capacitor C
4The other end link to each other diode D
1Anode and diode D
2Negative electrode and capacitor C
3An end link to each other, the anti-and switching tube of diode of described band and the control end of two-way power switch all receive the switch controlling signal that external equipment provides.
A kind of three-phase five level current transformers with two-way power switch comprise a capacitance link and three current transforming units;
Described capacitance link is made up of four electric capacity; Wherein, capacitor C
1An end link to each other capacitor C with the positive pole of outside direct voltage source
1The other end and capacitor C
2An end link to each other capacitor C
2The other end and capacitor C
3An end link to each other capacitor C
3The other end and capacitor C
4An end link to each other capacitor C
4The other end link to each other with the negative pole of outside direct voltage source;
Described current transforming unit is made up of two two-way power switch, two diodes and four band switching tubes anti-and diode; Wherein, the anti-also switching tube S of diode of band
1Input and capacitor C
1An end link to each other the switching tube S of the anti-and diode of band
1The switching tube S of output and diode anti-with band
2Input, two-way power switch Q
1An end and diode D
1Negative electrode link to each other two-way power switch Q
1The other end and capacitor C
2An end link to each other the switching tube S of the anti-and diode of band
2The switching tube S of output and diode anti-with band
3Input link to each other and be the level output end of corresponding phase, band is the switching tube S of diode also instead
3The switching tube S of output and diode anti-with band
4Input, two-way power switch Q
2An end and diode D
2Anode link to each other two-way power switch Q
2The other end and capacitor C
4An end link to each other the switching tube S of the anti-and diode of band
4Output and capacitor C
4The other end link to each other diode D
1Anode and diode D
2Negative electrode and capacitor C
3An end link to each other, the anti-and switching tube of diode of described band and the control end of two-way power switch all receive the switch controlling signal that external equipment provides.
Preferably, described band switching tube anti-and diode adopts IGBT.Existing IGBT technology makes its current range reach as high as 1500A, and electric pressure can reach 6500V, especially satisfies the powerful application scenario of mesohigh.
Described two-way power switch is made up of two IGBT; Wherein, The current collection of the one IGBT is an end of two-way power switch very; The emitter of the one IGBT links to each other with the emitter of the 2nd IGBT, and the current collection of the 2nd IGBT is the other end of two-way power switch very, and the gate pole of the gate pole of an IGBT and the 2nd IGBT is two control ends of two-way power switch.
Described two-way power switch is made up of two switching tubes; Wherein, The input of first switching tube links to each other with the output of second switch pipe and is an end of two-way power switch; First output end of switching tube links to each other with the input of second switch pipe and is that the other end of two-way power switch, the control end of first control end of switching tube and second switch pipe are two control ends of two-way power switch.
The two-way power switch of these two kinds of structures can independently be controlled the flow path of reversal, and path meritorious and reactive current is provided during for circuit output expectation level.The latter can pass through modular implementation with respect to the former, and volume is littler, the device count that electric current is flowed through still less, loss is also more little.
The utility model utilizes two-way power switch to align the independent control of negative current path, can control the electric current two-way flow on the two-way power switch, has guaranteed the output of the multiple level of circuit again; On the basis of five kinds of level of output, significantly reduced the quantity of power device and direct voltage source.
Two-way power switch is connected in switching tube S
1/ S
3With switching tube S
2/ S
4Between, this syndeton can directly use T type three level modules to realize, and then reduces system bulk, improves power density, and the voltage stress of two-way power switch is merely 1/4 of busbar voltage, and the topological structure symmetry makes things convenient for modularization production.
Description of drawings
Fig. 1 is the sketch map of conventional diode clamped five-level topological structure.
Fig. 2 is the sketch map of five level cascaded H bridge unsteady flow topological structures.
Fig. 3 is the sketch map of a kind of unsteady flow topological structure of the utility model instance.
Fig. 4 is the sketch map of the another kind of unsteady flow topological structure of the utility model instance.
Fig. 5 is the structural representation of the utility model three-phase five level current transformers.
Fig. 6 is the output line voltage oscillogram that the utility model three-phase five level current transformers connect star-like load.
Embodiment
In order to describe the utility model more particularly, be elaborated below in conjunction with accompanying drawing and embodiment technical scheme to the utility model.
As shown in Figure 3, a kind of five level unsteady flow topological structures with two-way power switch comprise a capacitance link and a current transforming unit;
Capacitance link is by four capacitor C
1~ C
4Form; Wherein, capacitor C
1An end link to each other capacitor C with the positive pole of outside direct voltage source
1The other end and capacitor C
2An end link to each other capacitor C
2The other end and capacitor C
3An end link to each other capacitor C
3The other end and capacitor C
4An end link to each other capacitor C
4The other end link to each other with the negative pole of outside direct voltage source;
Current transforming unit is by two two-way power switch Q
1~ Q
2, two diode D
1~ D
2With four IGBT S
1~ S
4Form; Wherein, IGBT S
1Collector electrode and capacitor C
1An end link to each other IGBT S
1Emitter and IGBTS
2Collector electrode, two-way power switch Q
1An end and diode D
1Negative electrode link to each other two-way power switch Q
1The other end and capacitor C
2An end link to each other IGBT S
2Emitter and IGBT S
3Collector electrode link to each other and be level output end, IGBT S
3Emitter and IGBT S
4Collector electrode, two-way power switch Q
2An end and diode D
2Anode link to each other two-way power switch Q
2The other end and capacitor C
4An end link to each other IGBT S
4Emitter and capacitor C
4The other end link to each other diode D
1Anode and diode D
2Negative electrode and capacitor C
3An end link to each other, the gate pole of IGBT and the control end of two-way power switch all receive the switch controlling signal that external equipment provides.
In this execution mode, two-way power switch is made up of two IGBT; Wherein, an IGBT S
5/ S
7A current collection end of two-way power switch very, an IGBT S
5/ S
7Emitter and the 2nd IGBT S
6/ S
8Emitter link to each other the 2nd IGBT S
6/ S
8The current collection other end of two-way power switch very, an IGBTS
5/ S
7Gate pole and the 2nd IGBT S
6/ S
8Gate pole be two control ends of two-way power switch.
As another kind of execution mode, as shown in Figure 4, the two-way power switch in the unsteady flow topological structure is made up of two switching tubes; Wherein, the first switching tube S
5/ S
7Input and second switch pipe S
6/ S
8Output link to each other and be an end of two-way power switch, the first switching tube S
5/ S
7Output and second switch pipe S
6/ S
8Input link to each other and be the other end of two-way power switch, the first switching tube S
5/ S
7Control end and second switch pipe S
6/ S
8Control end be two control ends of two-way power switch.
Topological structure with Fig. 4 is an example, and the output composition principle of five kinds of level is following:
Work as S
1, S
2With the S in the two-way power switch
6And S
8Open-minded, promptly break off S
3, S
4, S
5, S
7The time, this moment V
o=2E;
Work as S
2With the S in the two-way power switch
5, S
6, S
7Open-minded, promptly break off S
1, S
3, S
4, S
8The time, this moment V
o=1E;
Work as S
2, S
3With the S in the two-way power switch
5, S
8Open-minded, promptly break off S
1, S
4, S
6, S
7The time, this moment V
o=0E;
Work as S
3With the S in the two-way power switch
5, S
7, S
8Open-minded, promptly break off S
1, S
2, S
4, S
6The time, this moment V
o=-1E;
Work as S
3, S
4With the S in the two-way power switch
5, S
7Open-minded, promptly break off S
1, S
2, S
6, S
8The time, this moment V
o=-2E.
The five level unsteady flow topological structures of this execution mode both can directly constitute single-phase five level current transformers, can construct three-phase as shown in Figure 5 five level current transformers again; Three level output ends of three-phase five level current transformers of this execution mode topological structure are connected the star-like balanced load of three-phase respectively; Then its output line voltage waveform is as shown in Figure 6; The visible exportable line voltage with 9 kinds of level of current transformer from figure, output line voltage changes a level at every turn.
Claims (8)
1. five level unsteady flow topological structures with two-way power switch is characterized in that: comprise a capacitance link and a current transforming unit;
Described capacitance link is made up of four electric capacity; Wherein, capacitor C
1An end link to each other capacitor C with the positive pole of outside direct voltage source
1The other end and capacitor C
2An end link to each other capacitor C
2The other end and capacitor C
3An end link to each other capacitor C
3The other end and capacitor C
4An end link to each other capacitor C
4The other end link to each other with the negative pole of outside direct voltage source;
Described current transforming unit is made up of two two-way power switch, two diodes and four band switching tubes anti-and diode; Wherein, the anti-also switching tube S of diode of band
1Input and capacitor C
1An end link to each other the switching tube S of the anti-and diode of band
1The switching tube S of output and diode anti-with band
2Input, two-way power switch Q
1An end and diode D
1Negative electrode link to each other two-way power switch Q
1The other end and capacitor C
2An end link to each other the switching tube S of the anti-and diode of band
2The switching tube S of output and diode anti-with band
3Input link to each other and be level output end, band is the switching tube S of diode also instead
3The switching tube S of output and diode anti-with band
4Input, two-way power switch Q
2An end and diode D
2Anode link to each other two-way power switch Q
2The other end and capacitor C
4An end link to each other the switching tube S of the anti-and diode of band
4Output and capacitor C
4The other end link to each other diode D
1Anode and diode D
2Negative electrode and capacitor C
3An end link to each other, the anti-and switching tube of diode of described band and the control end of two-way power switch all receive the switch controlling signal that external equipment provides.
2. five level unsteady flow topological structures with two-way power switch according to claim 1 is characterized in that: described band switching tube anti-and diode adopts IGBT.
3. five level unsteady flow topological structures with two-way power switch according to claim 1, it is characterized in that: described two-way power switch is made up of two IGBT; Wherein, The current collection of the one IGBT is an end of two-way power switch very; The emitter of the one IGBT links to each other with the emitter of the 2nd IGBT, and the current collection of the 2nd IGBT is the other end of two-way power switch very, and the gate pole of the gate pole of an IGBT and the 2nd IGBT is two control ends of two-way power switch.
4. five level unsteady flow topological structures with two-way power switch according to claim 1, it is characterized in that: described two-way power switch is made up of two switching tubes; Wherein, The input of first switching tube links to each other with the output of second switch pipe and is an end of two-way power switch; First output end of switching tube links to each other with the input of second switch pipe and is that the other end of two-way power switch, the control end of first control end of switching tube and second switch pipe are two control ends of two-way power switch.
5. three-phase five level current transformers with two-way power switch is characterized in that: comprise a capacitance link and three current transforming units;
Described capacitance link is made up of four electric capacity; Wherein, capacitor C
1An end link to each other capacitor C with the positive pole of outside direct voltage source
1The other end and capacitor C
2An end link to each other capacitor C
2The other end and capacitor C
3An end link to each other capacitor C
3The other end and capacitor C
4An end link to each other capacitor C
4The other end link to each other with the negative pole of outside direct voltage source;
Described current transforming unit is made up of two two-way power switch, two diodes and four band switching tubes anti-and diode; Wherein, the anti-also switching tube S of diode of band
1Input and capacitor C
1An end link to each other the switching tube S of the anti-and diode of band
1The switching tube S of output and diode anti-with band
2Input, two-way power switch Q
1An end and diode D
1Negative electrode link to each other two-way power switch Q
1The other end and capacitor C
2An end link to each other the switching tube S of the anti-and diode of band
2The switching tube S of output and diode anti-with band
3Input link to each other and be the level output end of corresponding phase, band is the switching tube S of diode also instead
3The switching tube S of output and diode anti-with band
4Input, two-way power switch Q
2An end and diode D
2Anode link to each other two-way power switch Q
2The other end and capacitor C
4An end link to each other the switching tube S of the anti-and diode of band
4Output and capacitor C
4The other end link to each other diode D
1Anode and diode D
2Negative electrode and capacitor C
3An end link to each other, the anti-and switching tube of diode of described band and the control end of two-way power switch all receive the switch controlling signal that external equipment provides.
6. three-phase five level current transformers with two-way power switch according to claim 5 is characterized in that: described band switching tube anti-and diode adopts IGBT.
7. three-phase five level current transformers with two-way power switch according to claim 5, it is characterized in that: described two-way power switch is made up of two IGBT; Wherein, The current collection of the one IGBT is an end of two-way power switch very; The emitter of the one IGBT links to each other with the emitter of the 2nd IGBT, and the current collection of the 2nd IGBT is the other end of two-way power switch very, and the gate pole of the gate pole of an IGBT and the 2nd IGBT is two control ends of two-way power switch.
8. three-phase five level current transformers with two-way power switch according to claim 5, it is characterized in that: described two-way power switch is made up of two switching tubes; Wherein, The input of first switching tube links to each other with the output of second switch pipe and is an end of two-way power switch; First output end of switching tube links to each other with the input of second switch pipe and is that the other end of two-way power switch, the control end of first control end of switching tube and second switch pipe are two control ends of two-way power switch.
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|---|---|---|---|
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102664546A (en) * | 2012-05-18 | 2012-09-12 | 浙江大学 | Five-level current transformation topological structure with bi-directional power switch and applications thereof |
| CN103051231A (en) * | 2012-12-10 | 2013-04-17 | 阳光电源股份有限公司 | Three-phase five-level inverter |
| CN103475249A (en) * | 2013-09-11 | 2013-12-25 | 华为技术有限公司 | Multi-level inverter |
| CN103856089A (en) * | 2014-03-26 | 2014-06-11 | 南京理工大学 | High-frequency isolation-type five-level inverter |
| CN104578880A (en) * | 2015-01-16 | 2015-04-29 | 深圳市保益新能电气有限公司 | DC-AC conversion circuit and control method thereof |
| EP4362312A1 (en) * | 2022-10-27 | 2024-05-01 | Akademia Gorniczo-Hutnicza im. Stanislawa Staszica w Krakowie | Multilevel single-phase diode-clamped voltage inverter having a minimized number of transistors |
| EP4362313A1 (en) * | 2022-10-27 | 2024-05-01 | Akademia Gorniczo-Hutnicza im. Stanislawa Staszica w Krakowie | Multilevel diode-clamped voltage inverter with a minimized number of transistors |
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2012
- 2012-05-18 CN CN 201220229380 patent/CN202586797U/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102664546A (en) * | 2012-05-18 | 2012-09-12 | 浙江大学 | Five-level current transformation topological structure with bi-directional power switch and applications thereof |
| CN103051231A (en) * | 2012-12-10 | 2013-04-17 | 阳光电源股份有限公司 | Three-phase five-level inverter |
| CN103475249A (en) * | 2013-09-11 | 2013-12-25 | 华为技术有限公司 | Multi-level inverter |
| CN103475249B (en) * | 2013-09-11 | 2016-08-17 | 华为技术有限公司 | A kind of multi-electrical level inverter |
| CN103856089A (en) * | 2014-03-26 | 2014-06-11 | 南京理工大学 | High-frequency isolation-type five-level inverter |
| CN104578880A (en) * | 2015-01-16 | 2015-04-29 | 深圳市保益新能电气有限公司 | DC-AC conversion circuit and control method thereof |
| CN104578880B (en) * | 2015-01-16 | 2017-02-22 | 深圳市保益新能电气有限公司 | DC-AC conversion circuit and control method thereof |
| EP4362312A1 (en) * | 2022-10-27 | 2024-05-01 | Akademia Gorniczo-Hutnicza im. Stanislawa Staszica w Krakowie | Multilevel single-phase diode-clamped voltage inverter having a minimized number of transistors |
| EP4362313A1 (en) * | 2022-10-27 | 2024-05-01 | Akademia Gorniczo-Hutnicza im. Stanislawa Staszica w Krakowie | Multilevel diode-clamped voltage inverter with a minimized number of transistors |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20121205 Termination date: 20130518 |