CN105978375A - Cross-connected sub-module suitable for long-distance and large-capacity overhead line power transmission and MMC control method of cross-connected sub-module - Google Patents
Cross-connected sub-module suitable for long-distance and large-capacity overhead line power transmission and MMC control method of cross-connected sub-module Download PDFInfo
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- CN105978375A CN105978375A CN201610463228.3A CN201610463228A CN105978375A CN 105978375 A CN105978375 A CN 105978375A CN 201610463228 A CN201610463228 A CN 201610463228A CN 105978375 A CN105978375 A CN 105978375A
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
- H02M7/4835—Converters with outputs that each can have more than two voltages levels comprising two or more cells, each including a switchable capacitor, the capacitors having a nominal charge voltage which corresponds to a given fraction of the input voltage, and the capacitors being selectively connected in series to determine the instantaneous output voltage
Abstract
The invention discloses a cross-connected sub-module suitable for long-distance and large-capacity overhead line power transmission and an MMC control method of the cross-connected sub-module. The sub-module comprises six power switches and four capacitors. The sub-module can output a 4 level, a 0 level and a -2 level separately and has relatively high economy; a wider operation range can be provided on the basis of ensuring the DC fault self-cleaning capability; and the cross-connected sub-module is especially suitable for a flexible DC transmission system which is high in voltage class and high in transmission capacity and adopts overhead line transmission. An MMC formed by the cross-connected has the DC fault self-cleaning capability; the DC fault can be quickly and effectively processed; and the influences of the fault on the MMC and an overall AC/DC system are reduced.
Description
Technical field
The invention belongs to power electronic system technical field, be specifically related to one and be applicable to remote Large Copacity frame
The chiasma type submodule of ceases to be busy transmission of electricity and MMC control method thereof.
Background technology
High-voltage dc transmission based on modularization multi-level converter (modular multilevel converter, MMC)
Electricity is the focus of current academic research.MMC topology uses the mode that submodule (sub module, SM) cascades
Constitute, it is to avoid a large amount of switching devices are directly connected, and there is not the problems such as consistent triggering.Additionally, this topology
Also have that Harmonic Voltage aberration rate is low, be prone to encapsulation and safeguard, switching device bears that electric stress is little, open
Close and the advantages such as low is lost.
The most effectively processing DC Line Fault is the guardian technique difficult problem concerning Technology of HVDC based Voltage Source Converter development.
In existing MMC-HVDC engineering, MMC many by half-bridge submodule (half-bridge sub-module,
HBSM) constitute.Although HBSM has preferable economy, but it does not has DC Line Fault self-cleaning energy
Power.When system generation direct-current short circuit fault, the anti-paralleled diode in HBSM will provide for short circuit current
Circulation path, therefore system cannot carry out disengagement failure electric current by locking inverter.Big owing to being applicable to high pressure
The dc circuit breaker of power occasion is also not up to the level of commercial applications, therefore AC line in Practical Project
Road can only use failure rate is low, but the direct current cables involved great expense.At remote high-capacity direct current power transmission engineering
In, this mode will be substantially improved the overall cost of engineering undoubtedly, affect its economic benefit.
Propose multiple there is DC Line Fault from clear to effectively solve above-mentioned technical problem, educational circles and industrial quarters
The submodule topology of removing solid capacity, wherein with full-bridge submodule (full-bridge sub-module, FBSM) and clamp
Shuangzi module (clamp double sub-module, CDSM) is the most ripe.When system dc side is short-circuited former
During barrier, submodule is by quick lock.Now, brachium pontis will set up backward voltage by submodule electric capacity, thus
Fault current is made to drop to zero, to reach quickly to remove the purpose of DC Line Fault.
But both submodules disadvantageously, its equipment cost and running wastage are above HBSM.Same
Etc. situation, the twice that FBSM needs power electronic devices quantity to be HBSM, its running wastage also will increase
About 100%.CDSM has a distinct increment in economy compared to FBSM, but is limited to intellectual property and asks
Topic, this topology temporarily cannot obtain commercial applications in China, and this constrains China's flexible DC power transmission significantly
The development of cause.Additionally, be limited to existing manufacturing process, the power delivery capabilities of single submodule is less.
In Practical Project, in order to realize higher electric pressure and transmittability, the submodule quantity of every brachium pontis series connection
Being up to hundreds of, this all proposes high requirement to the modulation strategy of system with controller performance.Therefore,
Research one has stronger economy, and the submodule topology being more suitable for high-voltage large-capacity transmission of electricity occasion has
Highly important construction value and practical significance.
Summary of the invention
The present invention proposes a kind of chiasma type submodule being applicable to the transmission of electricity of remote Large Copacity aerial line
(cross-connected sub-module, CCSM) and MMC control method thereof, this submodule can export respectively
4 level, 0 level and-2 level, have stronger economy, can ensure DC Line Fault self-cleaning ability
On the basis of provide widely range of operation for inverter, be particularly suited for that electric pressure is high, transmission capacity
Greatly, the flexible direct current power transmission system of overhead transmission line transmission is used.
A kind of chiasma type submodule being applicable to the transmission of electricity of remote Large Copacity aerial line, including six power switch
S1～S6With four electric capacity C1～C4；Wherein:
Electric capacity C1Positive terminal and power switch S2Negative pole end be connected and constitute the height of described chiasma type submodule
Pressure side, electric capacity C1Negative pole end and power switch S1Positive terminal be connected, power switch S1Negative pole end with
Electric capacity C2Positive terminal and power switch S6Negative pole end be connected, electric capacity C2Negative pole end and power switch
S2Positive terminal and power switch S5Positive terminal be connected, power switch S5Negative pole end and electric capacity C3's
Positive terminal and power switch S3Negative pole end be connected, power switch S6Positive terminal and electric capacity C3Negative pole
End and power switch S4Positive terminal be connected, power switch S4Negative pole end and electric capacity C4Positive terminal phase
Even, electric capacity C4Negative pole end and power switch S3Positive terminal be connected and constitute the low of described chiasma type submodule
Pressure side.
Described power switch S1～S6By two IGBT pipe T1～T2It is composed in series；Wherein, IGBT pipe
T1Emitter stage as the positive terminal of power switch, IGBT pipe T1Colelctor electrode and IGBT pipe T2Transmitting
The most connected, IGBT pipe T2Colelctor electrode as the negative pole end of power switch, described IGBT pipe T1～T2Base
The switch controlling signal provided from external control devices is the most all provided；Described IGBT pipe T1～T2All reversely also
It is associated with diode.
Described chiasma type submodule has three kinds of operational modes: steady state mode of operation, troubleshooting pattern with
And capacitor voltage equalizing pattern；Wherein:
Under steady state mode of operation, chiasma type submodule only exports 4 level or 0 level: when being output as 4 level,
Power switch S1、S4、S5Open-minded, power switch S2、S3、S6Turn off；When being output as 0 level, merit
Rate switch S2、S3、S5Open-minded, power switch S1、S4、S6Turn off；
Under troubleshooting pattern, chiasma type submodule only exports 4 level or-2 level and power switch S1～S6All close
Disconnected；When bridge arm current is just, then it is output as 4 level；When bridge arm current is negative, then it is output as-2 level；
Under capacitor voltage equalizing pattern, chiasma type submodule only exports 0 level and by the following two kinds switch control logic
Realize: a kind of mode makes power switch S1、S3、S6Open-minded, power switch S2、S4、S5Turn off；Another
The mode of kind makes power switch S2、S4、S6Open-minded, power switch S1、S3、S5Turn off.
Use the MMC control method of above-mentioned chiasma type submodule, as follows:
Firstly, for arbitrary brachium pontis of MMC, utilize nearest level to approach modulator approach and determine subsequent time
Required electric capacity quantity N put into of this brachium pontisC, make electric capacity quantity NCIt is divided by with 4 and rounds downwards and i.e. obtain instantly
One moment required submodule number N put intoC/4；
Then, capacitance voltage meansigma methods U of brachium pontis each submodule current time is calculatedaveAnd press capacitance voltage
Meansigma methods UaveSize submodule all to brachium pontis is ranked up；Described capacitance voltage meansigma methods UaveIt is
The average voltage of four electric capacity in current time submodule；
And then judge: if current time bridge arm current is as just, then in subsequent time is to brachium pontis, capacitance voltage is put down
Average UaveMinimum NC/4Individual submodule applies 4 level triggers signals, and remaining submodule applies 0 level and touches
Signal；If current time bridge arm current is negative, then capacitance voltage meansigma methods U in subsequent time is to brachium pontisave
Maximum NC/4Individual submodule applies 4 level triggers signals, and remaining submodule applies 0 level triggers signal.
The switch control logic that described 4 level triggers signals are corresponding is: power switch S1、S4、S5It is open-minded,
Power switch S2、S3、S6Turn off；Described 0 level triggers signal correspondence have following three set switch control logics:
Pattern 1: power switch S2、S3、S5Open-minded, power switch S1、S4、S6Turn off；
Pattern 2: power switch S1、S3、S6Open-minded, power switch S2、S4、S5Turn off；
Pattern 3: power switch S2、S4、S6Open-minded, power switch S1、S3、S5Turn off.
Subsequent time is applied in arbitrary submodule of 0 level triggers signal, calculates this submodule of current time
Electric capacity C in block1With C3Voltage difference Udiff_13And electric capacity C2With C4Voltage difference Udiff_24；I.e.
Udiff_13=UC1-UC3, Udiff_24=UC2-UC4, UC1～UC4Correspond to electric capacity C in this submodule of current time1～C4
Magnitude of voltage；And then judge following four situation:
(1)|Udiff_13|≥|Udiff_24| and current time bridge arm current be just in the case of, first determine whether | Udiff_13|
＞ Δ Udiff: the most then determine whether Udiff_13＞ 0；If it is not, then this submodule is used at subsequent time
The switch control logic of associative mode 1；
Judge Udiff_13＞ 0: the most then determine whether | Udiff_24| ＞ Δ Udiff；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 2；
Judge | Udiff_24| ＞ Δ Udiff: the most then determine whether Udiff_24＞ 0；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 1；
Judge Udiff_24＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 3
Logic processed；If it is not, then this submodule is used the switch control logic of associative mode 1 at subsequent time.
(2)|Udiff_13|≥|Udiff_24| and in the case of current time bridge arm current is for bearing, first determine whether | Udiff_13|
＞ Δ Udiff: the most then determine whether Udiff_13＞ 0；If it is not, then this submodule is used at subsequent time
The switch control logic of associative mode 1；
Judge Udiff_13＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 2
Logic processed；If it is not, then determine whether | Udiff_24| ＞ Δ Udiff；
Judge | Udiff_24| ＞ Δ Udiff: the most then determine whether Udiff_24＞ 0；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 1；
Judge Udiff_24＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 1
Logic processed；If it is not, then this submodule is used the switch control logic of associative mode 3 at subsequent time.
(3)|Udiff_13| ＜ | Udiff_24| and current time bridge arm current be just in the case of, first determine whether | Udiff_24|
＞ Δ Udiff: the most then determine whether Udiff_24＞ 0；If it is not, then this submodule is used at subsequent time
The switch control logic of associative mode 1；
Judge Udiff_24＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 3
Logic processed；If it is not, then determine whether | Udiff_13| ＞ Δ Udiff；
Judge | Udiff_13| ＞ Δ Udiff: the most then determine whether Udiff_13＞ 0；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 1；
Judge Udiff_13＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 1
Logic processed；If it is not, then this submodule is used the switch control logic of associative mode 2 at subsequent time.
(4)|Udiff_13| ＜ | Udiff_24| and in the case of current time bridge arm current is for bearing, first determine whether | Udiff_24|
＞ Δ Udiff: the most then determine whether Udiff_24＞ 0；If it is not, then this submodule is used at subsequent time
The switch control logic of associative mode 1；
Judge Udiff_24＞ 0: the most then determine whether | Udiff_13| ＞ Δ Udiff；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 3；
Judge | Udiff_13| ＞ Δ Udiff: the most then determine whether Udiff_13＞ 0；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 1；
Judge Udiff_13＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 2
Logic processed；If it is not, then this submodule is used the switch control logic of associative mode 1 at subsequent time.
Compared with prior art, the Advantageous Effects of sub modular structure of the present invention is as follows:
(1) MMC being made up of submodule of the present invention has DC Line Fault self-cleaning ability, it is possible to quickly have
Effect ground processes DC Line Fault, reduces fault to MMC and the impact of whole ac and dc systems.
(2) compared with submodule CCSM with FBSM of the present invention, required power electronic devices number to lack, fortune
Row loss is low, and economy is higher；Compared with CDSM, needed for CCSM, the number of IGBT is the most, but
The negligible amounts of required diode, running wastage is suitable；The most in general, CCSM has with CDSM
Similar economic level.
(3) submodule maximum of the present invention can export four level, with HBSM 1 level of output and CDSM
Exporting 2 level to compare, in the MMC of identical electric pressure, the submodule of the present invention uses number minimum,
Can effectively reduce control hardware and the complexity of control algolithm.
Accompanying drawing explanation
Fig. 1 is the structural representation of chiasma type submodule of the present invention.
Fig. 2 (a) is chiasma type submodule 4 level running status schematic diagram of the present invention.
Fig. 2 (b) is the view that chiasma type submodule 0 level (pattern 1) of the present invention is run.
Fig. 2 (c) is that under chiasma type submodule blocking of the present invention, current direction is the view of A to B.
Fig. 2 (d) is that under chiasma type submodule blocking of the present invention, current direction is the view of B to A.
Fig. 2 (e) is the view that chiasma type submodule 0 level (pattern 2) of the present invention is run.
Fig. 2 (f) is the view that chiasma type submodule 0 level (pattern 3) of the present invention is run.
Fig. 3 is to calculate the required method schematic diagram putting into electric capacity quantity in MMC modulation strategy of the present invention.
Fig. 4 is to calculate required input submodule quantity and the stream of output level in MMC modulation strategy of the present invention
Journey schematic diagram.
Fig. 5 is to complete sorting operation also according to submodule capacitor voltage state in MMC modulation strategy of the present invention
Produce the schematic flow sheet triggering signal.
Detailed description of the invention
In order to more specifically describe the present invention, below in conjunction with the accompanying drawings and the detailed description of the invention skill to the present invention
Art scheme and relative theory thereof are described in detail.
As it is shown in figure 1, the chiasma type sub modular structure of modularization multi-level converter of the present invention, comprise 6
Switching tube S1～S4And 4 capacitor C1～C4；Wherein:
Electric capacity C1Positive terminal and switching tube S2Negative pole end be connected and constitute the high-pressure side of sub modular structure, electricity
Hold C1Negative pole end and switching tube S1Positive terminal be connected, switching tube S1Negative pole end and electric capacity C2Positive pole
End and switching tube S6Negative pole end be connected, electric capacity C2Negative pole end and switching tube S2Positive terminal and open
Close pipe S5Positive terminal be connected；Switching tube S5Negative pole end and electric capacity C3Positive terminal and switching tube S3's
Negative pole end is connected, switching tube S6Positive terminal and electric capacity C3Negative pole end and switching tube S4Positive terminal phase
Even, switching tube S4Negative pole end and electric capacity C4Positive terminal be connected, electric capacity C4Negative pole end and switching tube S3
Positive terminal be connected and constitute the low-pressure end of sub modular structure.
Switching tube S1～S6There is identical internal structure, comprise two IGBT pipe T1And T2And with its phase
Backward diode D in parallel1And D2.Wherein, IGBT pipe T1Emitter stage as No. 1 end of switching tube,
IGBT pipe T1Colelctor electrode and IGBT pipe T2Emitter stage be connected, IGBT pipe T2Colelctor electrode as opening
Close No. 2 ends of pipe.
Time properly functioning, submodule has 4 kinds of steady-state operating condition and 2 kinds of locking running statuses, such as table 1
Shown in:
Table 1
Chiasma type submodule of the present invention comprises following operational mode:
1. steady state mode of operation:
Steady state mode of operation is the basic method of operation of submodule；In such a mode, submodule only exports 4 electricity
Put down or 0 level (pattern 1).
As shown in Fig. 2 (a), when submodule output state is 4 level: S1、S4、S5Open-minded, S2、S3、
S6Turning off, electric current will flow through C1、S1、C2、S5、C3、S4And C4, now 4 electric capacity in submodule
To all put into, submodule port voltage is 4UC。
As shown in Fig. 2 (b), when submodule output state is 0 level (pattern 1): S2、S3、S5It is open-minded,
S1、S4、S6Turning off, electric current will flow through S2、S5And S3, now submodule puts into electric capacity number is 0, son
Module port voltage is 0.
Under this kind of method of operation, every 1 CCSM provides the ability of voltage with 4 HBSM quite, because of
This can regard 4 as with the combination opened with disconnected HBSM.4 HBSM can provide 0, UC、2UC、3UC、
4UCFive kinds of level, and CCSM provides 0 only, 4UCTwo kinds of level.In the occasion of submodule negligible amounts,
Total harmonic distortion factor THD is higher for its output voltage.Therefore, the applicable situation of this submodule is submodule quantity
More high-voltage large-capacity flexible DC power transmission engineering.
Under the method for operation of 4 level+0 level (pattern 1), in submodule, 4 electric capacity will put into simultaneously or cut
Removing, the electric current flowing through each electric capacity the most all keeps equal.Therefore, the feelings being more or less the same in capacitance
Under condition, can be approximated by modes such as increase equalizing resistances and ensure that the magnitude of voltage of each electric capacity is consistent, it is not necessary to introduce
Extra capacitance voltage balance policy.
2. troubleshooting pattern:
DC side is short-circuited after fault, and converter bridge arm electric current will increase sharply.When bridge arm current exceedes son
After module safety threshold value (such as the twice of steady state run current), submodule is by locking immediately.Submodule under blocking
The equivalent circuit of block is closely related with the sense of current.Under this pattern, all IGBT are all off.When electric current is
Timing, as shown in Fig. 2 (c), submodule port voltage is 4UC；When electric current is for bearing, as shown in Fig. 2 (d),
Submodule port voltage is-2UC。
It should be noted that when submodule operates in mode shown in Fig. 2 (d), only C in 4 electric capacity2、
C3Put into circuit, on the one hand receive DC network energy, on the other hand produce reverse potential, intercept exchange system
System is to the feed-in of trouble point energy.Generally, C2、C3Capacitance voltage will rise, and C1、
C4Capacitance voltage keep constant.Therefore, in order in ensureing submodule, 4 capacitance voltages substantially equalize, should
Corresponding capacitor voltage balance strategy is used after unlocking state, to prevent the problems such as generator part overvoltage,
Affect the service life of submodule.
3. capacitor voltage equalizing pattern:
When DC Line Fault occur, after submodule locking, C in submodule2、C3Capacitance voltage will change.
Now can make the voltage weight of 4 electric capacity by the way of submodule is applied 0 level (pattern 2 or pattern 3)
Newly recover equilibrium.
As shown in Fig. 2 (e), in 0 level (pattern 2), S1、S3、S6Open-minded, S2、S4、S5Turn off；Such as figure
Shown in 2 (f), in 0 level (pattern 3), S2、S4、S6Open-minded, S1、S3、S5Turn off.With under pattern 1
0 level is different, and the principle that realizes of 0 level under pattern 2 or pattern 3 is not to bypass all electric capacity, but throws
Enter the electric capacity of a pair voltage reversal, 0 level (pattern 2) is C1、C3, 0 level (pattern 3) is C2、
C4, C is balanced respectively with this1、C3And C2、C4Between capacitance voltage.
If submodule is after lock operation, C2、C3Capacitance voltage become U simultaneouslyC', C1、C4Electricity
Hold voltage and keep UCConstant.In order to balance the voltage between these 4 electric capacity, submodule can be first made to operate in 0
Under level (pattern 2), if C1、C3Capacitance approximately equal, then C1、C3Capacitance voltage will become
(UC’+UC)/2；Then, submodule is made to operate under 0 level (pattern 3), then C2、C4Capacitance voltage also
(U will be becomeC’+UC)/2.Now, in submodule, the voltage of four electric capacity will recover equal again.
Additionally, submodule capacitor voltage balanced threshold Δ U can be manually setdiff.If C1、C3Or C2、C4Between
Voltage deviation less, be not above threshold value, then submodule is without carrying out equal press operation, with reduce control plan
Complexity slightly.
As follows based on the submodule modulation strategy operating above pattern:
(1) the required quantity putting into electric capacity is calculated.
This step is consistent with conventional measures, as it is shown on figure 3, first calculate bridge arm voltage reference value Uarm_ref,
Afterwards with capacitance voltage reference value UC_refIt is divided by, electric capacity quantity N that this moment brachium pontis need to put into can be drawnC。
(2) required input submodule quantity and output level state are calculated.
Under steady state mode of operation, submodule only exports 4 level and 0 level, and therefore its calculation is relatively
For simply.Only need to be by required input electric capacity quantity NCIt is divided by with 4 and rounds, i.e. can get 4 level and put into number
Amount N4。
(3) complete sorting operation according to submodule capacitor voltage state, and produce triggering signal.
The main purpose of this step is: first ensure capacitive energy summation approximate equality between each submodule, secondly
Promote each capacitive energy approximate equality in submodule.
For first purpose, its main realization rate is for controlling whether it puts into.If submodule output state
Be 4 level, then in submodule, 4 electric capacity all will be charged according to the difference of the sense of current or discharge；If
Submodule output state is 0 level, then in submodule, 4 capacitive energy summations are constant.When switching operates,
First meansigma methods U of 4 capacitance voltages in each submodule is obtainedave, and the U to each submoduleaveCarry out
Sequence.Assuming that 4 level needed for a certain moment put into number is N4If bridge arm current is just, then should be according to Uave
Order from low to high, to front N4Individual submodule applies 4 level triggers signals, and remaining submodule is applied 0
Level triggers signal.Otherwise, if bridge arm current is negative, then should be according to UaveOrder from high to low, to front
N4Individual submodule applies 4 level triggers signals, and remaining submodule applies 0 level triggers signal；Concrete stream
Journey is as shown in Figure 4.
For second point purpose, its main realization rate is the output mode controlling its 0 level.Definition C1With
C3Between voltage difference be Udiff_13, C2With C4Between voltage difference be Udiff_24.Assume Udiff_13Absolute value big
In Udiff_24Absolute value, and exceeded the balance of voltage threshold value Δ U being manually setdiff, then should first consider
C1With C3Between balance.If bridge arm current is just, then primarily look at Udiff_13Whether more than 0, if C1
Voltage less than C3Voltage, then submodule output state should be 0 level (pattern 2).Otherwise, if C1's
Voltage is more than C3Voltage, then should not be considered 0 level (pattern 2), otherwise C1Will charging, C3To discharge,
Continuation is increased by the voltage difference between electric capacity.Now investigate Udiff_24Size, if C2Voltage more than C4
Voltage, and exceeded the balance of voltage threshold value Δ U being manually setdiff, then submodule output state should be 0 electricity
Flat (pattern 3)；Otherwise, submodule output state should be 0 level (pattern 1).Idiographic flow is as shown in Figure 5.
The above-mentioned description to embodiment is to be understood that for ease of those skilled in the art and apply
The present invention.Above-described embodiment obviously easily can be made various amendment by person skilled in the art,
And General Principle described herein is applied in other embodiments without through performing creative labour.Therefore,
The invention is not restricted to above-described embodiment, those skilled in the art, according to the announcement of the present invention, do for the present invention
The improvement and the amendment that go out all should be within protection scope of the present invention.
Claims (6)
1. the chiasma type submodule being applicable to the transmission of electricity of remote Large Copacity aerial line, it is characterised in that: bag
Include six power switch S1～S6With four electric capacity C1～C4；Wherein:
Electric capacity C1Positive terminal and power switch S2Negative pole end be connected and constitute the height of described chiasma type submodule
Pressure side, electric capacity C1Negative pole end and power switch S1Positive terminal be connected, power switch S1Negative pole end with
Electric capacity C2Positive terminal and power switch S6Negative pole end be connected, electric capacity C2Negative pole end and power switch
S2Positive terminal and power switch S5Positive terminal be connected, power switch S5Negative pole end and electric capacity C3's
Positive terminal and power switch S3Negative pole end be connected, power switch S6Positive terminal and electric capacity C3Negative pole
End and power switch S4Positive terminal be connected, power switch S4Negative pole end and electric capacity C4Positive terminal phase
Even, electric capacity C4Negative pole end and power switch S3Positive terminal be connected and constitute the low of described chiasma type submodule
Pressure side.
Chiasma type submodule the most according to claim 1, it is characterised in that: described power switch
S1～S6By two IGBT pipe T1～T2It is composed in series；Wherein, IGBT pipe T1Emitter stage as power
The positive terminal of switch, IGBT pipe T1Colelctor electrode and IGBT pipe T2Emitter stage be connected, IGBT pipe T2
Colelctor electrode as the negative pole end of power switch, described IGBT pipe T1～T2Base stage all receive from outside control
The switch controlling signal that control equipment provides；Described IGBT pipe T1～T2All reverse parallel connections have diode.
Chiasma type submodule the most according to claim 1, it is characterised in that: described chiasma type submodule
Block has three kinds of operational modes: steady state mode of operation, troubleshooting pattern and capacitor voltage equalizing pattern；Wherein:
Under steady state mode of operation, chiasma type submodule only exports 4 level or 0 level: when being output as 4 level,
Power switch S1、S4、S5Open-minded, power switch S2、S3、S6Turn off；When being output as 0 level, merit
Rate switch S2、S3、S5Open-minded, power switch S1、S4、S6Turn off；
Under troubleshooting pattern, chiasma type submodule only exports 4 level or-2 level and power switch S1～S6All close
Disconnected；When bridge arm current is just, then it is output as 4 level；When bridge arm current is negative, then it is output as-2 level；
Under capacitor voltage equalizing pattern, chiasma type submodule only exports 0 level and by the following two kinds switch control logic
Realize: a kind of mode makes power switch S1、S3、S6Open-minded, power switch S2、S4、S5Turn off；Another
The mode of kind makes power switch S2、S4、S6Open-minded, power switch S1、S3、S5Turn off.
4. using a MMC control method for chiasma type submodule as claimed in claim 1, its feature exists
In:
Firstly, for arbitrary brachium pontis of MMC, utilize nearest level to approach modulator approach and determine subsequent time
Required electric capacity quantity N put into of this brachium pontisC, make electric capacity quantity NCIt is divided by with 4 and rounds downwards and i.e. obtain instantly
One moment required submodule number N put intoC/4；
Then, capacitance voltage meansigma methods U of brachium pontis each submodule current time is calculatedaveAnd press capacitance voltage
Meansigma methods UaveSize submodule all to brachium pontis is ranked up；Described capacitance voltage meansigma methods UaveIt is
The average voltage of four electric capacity in current time submodule；
And then judge: if current time bridge arm current is as just, then in subsequent time is to brachium pontis, capacitance voltage is put down
Average UaveMinimum NC/4Individual submodule applies 4 level triggers signals, and remaining submodule applies 0 level and touches
Signal；If current time bridge arm current is negative, then capacitance voltage meansigma methods U in subsequent time is to brachium pontisave
Maximum NC/4Individual submodule applies 4 level triggers signals, and remaining submodule applies 0 level triggers signal.
MMC control method the most according to claim 4, it is characterised in that: described 4 level triggers
The switch control logic that signal is corresponding is: power switch S1、S4、S5Open-minded, power switch S2、S3、S6
Turn off；Described 0 level triggers signal correspondence have following three set switch control logics:
Pattern 1: power switch S2、S3、S5Open-minded, power switch S1、S4、S6Turn off；
Pattern 2: power switch S1、S3、S6Open-minded, power switch S2、S4、S5Turn off；
Pattern 3: power switch S2、S4、S6Open-minded, power switch S1、S3、S5Turn off.
MMC control method the most according to claim 5, it is characterised in that: for subsequent time quilt
Apply arbitrary submodule of 0 level triggers signal, calculate electric capacity C in this submodule of current time1With C3Electricity
Pressure reduction Udiff_13And electric capacity C2With C4Voltage difference Udiff_24；I.e. Udiff_13=UC1-UC3,
Udiff_24=UC2-UC4, UC1～UC4Correspond to electric capacity C in this submodule of current time1～C4Magnitude of voltage；Enter
And judge following four situation:
(1)|Udiff_13|≥|Udiff_24| and current time bridge arm current be just in the case of, first determine whether | Udiff_13|
＞ Δ Udiff: the most then determine whether Udiff_13＞ 0；If it is not, then this submodule is used at subsequent time
The switch control logic of associative mode 1；
Judge Udiff_13＞ 0: the most then determine whether | Udiff_24| ＞ Δ Udiff；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 2；
Judge | Udiff_24| ＞ Δ Udiff: the most then determine whether Udiff_24＞ 0；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 1；
Judge Udiff_24＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 3
Logic processed；If it is not, then this submodule is used the switch control logic of associative mode 1 at subsequent time；
(2)|Udiff_13|≥|Udiff_24| and in the case of current time bridge arm current is for bearing, first determine whether | Udiff_13|
＞ Δ Udiff: the most then determine whether Udiff_13＞ 0；If it is not, then this submodule is used at subsequent time
The switch control logic of associative mode 1；
Judge Udiff_13＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 2
Logic processed；If it is not, then determine whether | Udiff_24| ＞ Δ Udiff；
Judge | Udiff_24| ＞ Δ Udiff: the most then determine whether Udiff_24＞ 0；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 1；
Judge Udiff_24＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 1
Logic processed；If it is not, then this submodule is used the switch control logic of associative mode 3 at subsequent time；
(3)|Udiff_13| ＜ | Udiff_24| and current time bridge arm current be just in the case of, first determine whether | Udiff_24|
＞ Δ Udiff: the most then determine whether Udiff_24＞ 0；If it is not, then this submodule is used at subsequent time
The switch control logic of associative mode 1；
Judge Udiff_24＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 3
Logic processed；If it is not, then determine whether | Udiff_13| ＞ Δ Udiff；
Judge | Udiff_13| ＞ Δ Udiff: the most then determine whether Udiff_13＞ 0；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 1；
Judge Udiff_13＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 1
Logic processed；If it is not, then this submodule is used the switch control logic of associative mode 2 at subsequent time；
(4)|Udiff_13| ＜ | Udiff_24| and in the case of current time bridge arm current is for bearing, first determine whether | Udiff_24|
＞ Δ Udiff: the most then determine whether Udiff_24＞ 0；If it is not, then this submodule is used at subsequent time
The switch control logic of associative mode 1；
Judge Udiff_24＞ 0: the most then determine whether | Udiff_13| ＞ Δ Udiff；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 3；
Judge | Udiff_13| ＞ Δ Udiff: the most then determine whether Udiff_13＞ 0；If it is not, then at subsequent time
This submodule is used the switch control logic of associative mode 1；
Judge Udiff_13＞ 0: the most then at subsequent time, this submodule is used the switch control of associative mode 2
Logic processed；If it is not, then this submodule is used the switch control logic of associative mode 1 at subsequent time.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113176428A (en) * | 2021-03-16 | 2021-07-27 | 上海交通大学 | Current distortion eliminating system and method for working condition simulation of cascaded converter |
| CN113300622A (en) * | 2021-04-14 | 2021-08-24 | 昆明理工大学 | Five-level clamping cross type submodule topological structure of modular multilevel converter |
| CN117498711A (en) * | 2023-09-26 | 2024-02-02 | 华南理工大学 | Energy storage type MMC submodule circuit with direct-current fault clearing capacity and working method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011124260A1 (en) * | 2010-04-08 | 2011-10-13 | Areva T&D Uk Limited | Modularised converter for hvdc and statcom |
| CN104167912A (en) * | 2014-08-14 | 2014-11-26 | 华中科技大学 | MMC with zero direct voltage fault ride-through capability and design method thereof |
| CN104638615A (en) * | 2015-02-16 | 2015-05-20 | 天津大学 | Modular multilevel converter with direct-current fault isolation function and submodule thereof |
| CN104779825A (en) * | 2015-03-20 | 2015-07-15 | 浙江大学 | Cross type sub-module structure of modular multilevel converter (MMC) |
| CN104821736A (en) * | 2015-05-15 | 2015-08-05 | 国家电网公司 | Modularized multi-level converter with function of DC side short circuit protection |
| CN104993716A (en) * | 2015-07-01 | 2015-10-21 | 许继集团有限公司 | Modular multilevel converter and hybrid double-unit sub-module |
-
2016
- 2016-06-21 CN CN201610463228.3A patent/CN105978375B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011124260A1 (en) * | 2010-04-08 | 2011-10-13 | Areva T&D Uk Limited | Modularised converter for hvdc and statcom |
| CN104167912A (en) * | 2014-08-14 | 2014-11-26 | 华中科技大学 | MMC with zero direct voltage fault ride-through capability and design method thereof |
| CN104638615A (en) * | 2015-02-16 | 2015-05-20 | 天津大学 | Modular multilevel converter with direct-current fault isolation function and submodule thereof |
| CN104779825A (en) * | 2015-03-20 | 2015-07-15 | 浙江大学 | Cross type sub-module structure of modular multilevel converter (MMC) |
| CN104821736A (en) * | 2015-05-15 | 2015-08-05 | 国家电网公司 | Modularized multi-level converter with function of DC side short circuit protection |
| CN104993716A (en) * | 2015-07-01 | 2015-10-21 | 许继集团有限公司 | Modular multilevel converter and hybrid double-unit sub-module |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113176428A (en) * | 2021-03-16 | 2021-07-27 | 上海交通大学 | Current distortion eliminating system and method for working condition simulation of cascaded converter |
| CN113176428B (en) * | 2021-03-16 | 2022-05-03 | 上海交通大学 | Current distortion eliminating system and method for working condition simulation of cascaded converter |
| CN113300622A (en) * | 2021-04-14 | 2021-08-24 | 昆明理工大学 | Five-level clamping cross type submodule topological structure of modular multilevel converter |
| CN113300622B (en) * | 2021-04-14 | 2023-11-17 | 昆明理工大学 | Five-level clamping cross type sub-module topological structure of modularized multi-level converter |
| CN117498711A (en) * | 2023-09-26 | 2024-02-02 | 华南理工大学 | Energy storage type MMC submodule circuit with direct-current fault clearing capacity and working method |
| CN117498711B (en) * | 2023-09-26 | 2024-05-07 | 华南理工大学 | Energy storage type MMC submodule circuit with direct-current fault clearing capacity and working method |
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