CN103066582A - Overvoltage protection method and overvoltage protection devices of modular multi-level converters - Google Patents
Overvoltage protection method and overvoltage protection devices of modular multi-level converters Download PDFInfo
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- CN103066582A CN103066582A CN2012105372853A CN201210537285A CN103066582A CN 103066582 A CN103066582 A CN 103066582A CN 2012105372853 A CN2012105372853 A CN 2012105372853A CN 201210537285 A CN201210537285 A CN 201210537285A CN 103066582 A CN103066582 A CN 103066582A
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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
- 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
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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
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
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Abstract
The invention relates to an overvoltage protection method and overvoltage protection devices of modular multi-level converters. The overvoltage protection method comprises the following steps of arranging the overvoltage protection devices of the modular multi-level converters between alternating current ends of the modular multi-level converters and the ground, or between direct current ends and the ground, or between the alternating current ends, or between the direct current ends or more than one of the positions at the same time, setting operation voltage parameters of lightning arresters, setting operation voltages of discharging circuits and setting delay operation time of the discharging circuits, wherein each overvoltage protection device comprises the discharging circuit, a voltage-sharing damping circuit and the lightning arrester, the operation voltage parameters of the lightning arresters comprise reference voltages, operation overvoltage protection levels, lightning overvoltage protection levels and steep wave overvoltage protection levels, and the operation voltages of the discharging circuits are set according to expected invasion power frequency overvoltage levels. By means of the overvoltage protection method and the overvoltage protection devices of the modular multi-level converters, economical efficiency and reliability of the modular multi-level converters are improved.
Description
Technical field
The present invention relates to converter method of overvoltage protection and device, be specifically related to a kind of modularization multi-level converter method of overvoltage protection and protector thereof.
Background technology
Modularization multi-level converter (Modular Multilevel Converter, MMC) is a kind of take the novel converter of turn-off device as the basis.The most normal turn-off device that is used is igbt (IGBT) at present.Modularization multi-level converter (such as Fig. 1) comprises submodule 1 and converter reactor 2, and each exchanges between end (A, B, C) and the dc terminal (P, N) and is being connected in series one or more submodules and converter reactor at it.Main element in the submodule comprises IGBT, FWD, resistor R and capacitor C, and typical sub modular structure comprises half-bridge submodule (such as Fig. 2) and full-bridge submodule (such as Fig. 3).Traditional line voltage commutation converter (Line Commutated Converter, LCC) belongs to the current source type converter, and converter output voltage amplitude in service and polarity change.Modularization multi-level converter has used a large amount of energy storage capacitors, by the module superimposing technique converter output voltage waveforms in service is remained unchanged simultaneously, belongs to the voltage-source type converter.Therefore, consider that from the stable angle of Operating Voltage modularization multi-level converter has obvious advantage.
Existing method of overvoltage protection mainly uses lightning arrester that switching overvoltage, lightning overvoltage and the steep wave overvoltage of invasion converter are protected.Lightning arrester also becomes the basic implement device of Hyper-Voltage of Power Systems protection and insulation coordination.Denomination of invention provides a kind of like this method of overvoltage protection for " system that is used for overvoltage protection " patent No. ZL 01813089.5.The method arranges lightning arrester between interchange phase line and ground, the overvoltage ripple of absorption circuit invasion.The energy absorption capability that is limited to lightning arrester; enough height that when using the method, the rated voltage Ur of lightning arrester need to be arranged; lightning arrester generation thermal runaway when preventing power-frequency overvoltage and blast occurs has correspondingly improved insulation level and the cost of overvoltage protection level and the protected equipment of lightning arrester.
The another kind of over-voltage of prior art is to use the discharging gap of self recovery to carry out overvoltage protection to the method for protected equipment harm.Denomination of invention is " a kind of 1000kV UHVAC transmission line live line working is with protecting the gap ", and publication number provides a kind of typical overvoltage protection gap for CN101335430B.Provide limited overvoltage protection ability by the control gap discharge voltage to protected object.Because gap electrical field is generally inhomogeneous field; or even severe non-uniform electric field; its discharge voltage particularly has certain deviation from randomness under switching overvoltage ripple and the lightning overvoltage ripple, thereby the switching overvoltage of protected object and the protection of lightning overvoltage are existed scarcely certainty and insecurity.
Summary of the invention
For the deficiencies in the prior art, the invention provides a kind of modularization multi-level converter method of overvoltage protection and protector thereof, improve economy and the reliability of modularization multi-level converter.
The objective of the invention is to adopt following technical proposals to realize:
A kind of modularization multi-level converter method of overvoltage protection, its improvements are that described method comprises the steps:
Step 1: the modularization multi-level converter excess voltage preventer is set: described excess voltage preventer with individually, two and the above mode that is connected in series or two and the above mode of being connected in parallel be arranged on that modularization multi-level converter exchanges between end and the ground, between dc terminal and the ground, exchanges between holding, between the dc terminal or is arranged at simultaneously above-mentioned position greater than one;
Step 2: the operation voltage parameter that lightning arrester is set: the operation voltage parameter of lightning arrester comprises: reference voltage U
Ref, switching-surge protective level SIPL, the horizontal LIPL of atmospheric over voltage protection and steep wave overvoltage protection level STIPL;
Step 3: the operation voltage U that discharge circuit is set
g: the operation voltage of discharge circuit is according to the expection invasion power-frequency overvoltage level set of modularization multi-level converter;
Step 4: the time-delay action that discharge circuit is set.
Wherein, in the described step 1, described modularization multi-level converter excess voltage preventer comprises discharge circuit, equal pressure drag Buddhist nun circuit and lightning arrester; Described discharge circuit one end, equal pressure drag Buddhist nun circuit high-pressure section one end are electrically connected with lightning arrester one end is in the same place; The described discharge circuit other end, equal pressure drag Buddhist nun circuit low-pressure section one end are electrically connected with the lightning arrester other end is in the same place;
Discharging gap in the described discharge loop moves when power-frequency overvoltage occurs.
Wherein, described equal pressure drag Buddhist nun circuit is used for: the voltage that discharge circuit discharging gap and discharge trigger element are born distributes by the high-pressure section of equal pressure drag Buddhist nun circuit and the resistance value of low-pressure section; 2) the triggering control section for discharge trigger element in the discharge circuit provides the measurement input; 3) discharging current for capacity cell provides damping when discharging gap or lightning arrestor movement.
Wherein, described lightning arrester is metal oxide arrester, the switching overvoltage, lightning overvoltage and the steep wave overvoltage that suffer for reducing modularization multi-level converter; When the reference voltage of lightning arrester is U
RefThe time, the preferred value of the switching-surge protective level of lightning arrester is the U of 1.5 ~ 1.8p.u
Ref, the preferred value of atmospheric over voltage protection level is the U of 1.8 ~ 2.2p.u
Ref, the preferred value of steep wave overvoltage protection level is the U of 2.2 ~ 2.5p.u.
Ref
Wherein, in the described step 2, according to the continuous operating voltage U of modularization multi-level converter
cOr maximum direct current crest voltage PCOV, determine the operation voltage parameter of lightning arrester with reference to standard GB/T 311.1-1997 " insulation coordination of high-tension power transmission and transformation equipment " and power industry standard DL/T605-1996 " HVDC (High Voltage Direct Current) converter substation insulation coordination guide rule "; The unit of described lightning arrestor movement voltage parameter, continuous operating voltage and maximum direct current crest voltage is kV.
Wherein, in the described step 3, the operation voltage U of discharge circuit
gBe the frequency breakdown voltage of its discharging gap, unit is kV, and its value is the expection invasion power-frequency overvoltage peak-peak of 0.52 ~ 0.58p.u.; The peak-peak of expection invasion power-frequency overvoltage is decided by the normal working voltage of protected equipment, and for the modularization multi-level converter that works in 110kV ~ 750kV AC network, its scope is at 90kV ~ 1060kV.
Wherein, in the described step 4, the discharging gap in the discharge circuit is bearing operation voltage U
gMove through behind the time-delay action, time-delay action unit is ms again, and its value is 100 ~ 250ms.
The present invention is based on a kind of modularization multi-level converter excess voltage preventer that another purpose provides, its improvements are that described excess voltage preventer comprises discharge circuit, equal pressure drag Buddhist nun circuit and lightning arrester; Described discharge circuit one end, equal pressure drag Buddhist nun circuit high-pressure section one end are electrically connected with lightning arrester one end is in the same place; The described discharge circuit other end, equal pressure drag Buddhist nun circuit low-pressure section one end are electrically connected with the lightning arrester other end is in the same place;
Described excess voltage preventer with individually, two and the above mode that is connected in series or two and the above mode of being connected in parallel be arranged on that modularization multi-level converter exchanges between end and the ground, between dc terminal and the ground, exchanges between holding, between the dc terminal or is arranged at simultaneously above-mentioned position greater than one.
Wherein, described discharge circuit is composed in series by discharging gap and discharge trigger element; Described discharge trigger element is comprised of two antiparallel thyristors; Described equal pressure drag Buddhist nun circuit is composed in series by high-pressure section and low-pressure section, and the high-pressure section of described equal pressure drag Buddhist nun circuit and low-pressure section all have three kinds of forms, comprising: resistance and Capacitance parallel connection, resistance and capacitances in series, single resistance.
Wherein, described discharging gap be shaped as rod-rod gap, discharging gap apart from d according to the operation voltage of discharging gap according to d=0.1859U
gDetermine that discharging gap is cm apart from the unit of d.
Wherein, described discharging gap is bearing operation voltage U
gMove through behind the time-delay action, time-delay action unit is ms again, and its value is 100 ~ 250ms.
Wherein, the high-pressure section with discharging gap in the discharge circuit and equal pressure drag Buddhist nun circuit is connected in parallel; The low-pressure section of discharge trigger element in the discharge circuit and equal pressure drag Buddhist nun circuit is connected in parallel; Capacitor C in its equal pressure drag Buddhist nun circuit
1And C
2Value be 300 ~ 8000pF, resistor R
1And R
2Value be 50 ~ 600k Ω, resistor parameter and capacitor parameters satisfy: R
1C
1=R
2C
2
Wherein, described lightning arrester is metal oxide arrester, the switching overvoltage, lightning overvoltage and the steep wave overvoltage that suffer for reducing modularization multi-level converter; When the reference voltage of lightning arrester is U
RefThe time, the preferred value of the switching-surge protective level of lightning arrester is the U of 1.5 ~ 1.8p.u
Ref, the preferred value of atmospheric over voltage protection level is the U of 1.8 ~ 2.2p.u
Ref, the preferred value of steep wave overvoltage protection level is the U of 2.2 ~ 2.5p.u.
Ref
Compared with the prior art, the beneficial effect that reaches of the present invention is:
1. the present invention adopts discharging gap to suppress the modularization multi-level converter dc terminal or exchanges the power-frequency overvoltage of holding; the power-frequency overvoltage tolerance that has reduced lightning arrester requires and the temporary overvoltage level of protection; thereby the insulation level of modularization multi-level converter is reduced; reduce equipment manufacturing cost, improved economy.
2. the present invention adopts lightning arrester to suppress the modularization multi-level converter dc terminal or exchanges switching overvoltage, lightning overvoltage and the steep wave overvoltage of holding, the energy absorption capability of the lightning arrester that prior art is made is larger, can provide modularization multi-level converter to the superpotential abundant protective capacities of switching overvoltage, lightning overvoltage and steep wave, the fail safe that has improved modularization multi-level converter.
3. the present invention adopts equal pressure drag Buddhist nun circuit, can be discharging gap or lightning arrestor movement after the capacity cell discharging current damping is provided, be reduced in modularization multi-level converter and exchange transient state concussion voltage magnitude and the frequency that end or dc terminal occur.
Description of drawings
Fig. 1 is modular multilevel converter structure;
Fig. 2 is the inner semi-bridge type sub modular structure of modularization multi-level converter in the embodiment of the invention;
Fig. 3 is the inner bridge-type sub modular structure of modularization multi-level converter in the embodiment of the invention;
Fig. 4 is a kind of preferred implementation of modularization multi-level converter excess voltage preventer in the embodiment of the invention;
Fig. 5 is the flow chart of modularization multi-level converter method of overvoltage protection in the embodiment of the invention;
Fig. 6 is the first execution mode of modularization multi-level converter method of overvoltage protection in the embodiment of the invention;
Fig. 7 is the second execution mode of modularization multi-level converter method of overvoltage protection in the embodiment of the invention.
Embodiment
Below in conjunction with accompanying drawing the specific embodiment of the present invention is described in further detail.
In the embodiment of the invention a kind of preferred implementation of modularization multi-level converter excess voltage preventer as shown in Figure 4, excess voltage preventer comprises discharge circuit, all pressure drag Buddhist nun circuit and lightning arrester 7; Its discharge circuit is composed in series by discharging gap 3 and discharge trigger element 4; Its equal pressure drag Buddhist nun circuit is composed in series by high-pressure section 5 and low-pressure section 6, high-pressure section or/and low-pressure section formed by serial or parallel connection by capacitor C and/or resistor R; A kind of preferred version as shown in Figure 4, in its discharge circuit discharging gap 3 and all the high-pressure section 5 of pressure drag Buddhist nun circuit be connected in parallel; The low-pressure section 6 of discharge trigger element 4 and equal pressure drag Buddhist nun circuit is connected in parallel in its discharge circuit; High-pressure section 5 comprises resistor R in parallel
1With capacitor C
1Low-pressure section 6 comprises resistor R in parallel
2With capacitor C
2Its capacitor C
1And C
2Representative value be 300 ~ 8000pF, resistor R
1And R
2Representative value be 50 ~ 600k, resistance parameter and capacitance parameter satisfy: R
1C
1=R
2C
2
All pressure drag Buddhist nun circuit high-pressure section 5 one end N51, discharge circuit one end N31 are electrically connected respectively with lightning arrester 7 one end N71 and are in the same place, and its equal pressure drag Buddhist nun circuit low-pressure section 6 one end N62, discharge circuit one end N42 are electrically connected respectively with lightning arrester 7 one end N72 and are in the same place; The position of described excess voltage preventer with individually, two and the above mode that is connected in series or two and the above mode of being connected in parallel be arranged on that modularization multi-level converter exchanges between end and the ground, between dc terminal and the ground, exchanges between holding, between the dc terminal or is arranged at simultaneously above-mentioned position greater than one.
The power-frequency overvoltage that discharging gap suffers for reducing modularization multi-level converter in the discharge circuit.Wherein, discharging gap be shaped as rod-rod gap, discharging gap can be according to the operation voltage of discharging gap according to d=0.1859U apart from d
gDetermine that the unit of clearance distance d is cm.
To described modularization multi-level converter excess voltage preventer, discharging gap 3 should not move after having born operation voltage immediately in its discharge circuit, the strategy that should adopt deferred action described protective device when guaranteeing the discharging gap action suppresses object as power-frequency overvoltage, avoids malfunction under switching overvoltage, lightning overvoltage and steep wave overvoltage; The time-delay action representative value of its discharge circuit is 100 ~ 250ms.
To described modularization multi-level converter excess voltage preventer, an effect of its equal pressure drag Buddhist nun circuit is that the voltage that discharging gap in the discharge circuit 3 and discharge trigger element 4 are born distributes by the high-pressure section 5 of equal pressure drag Buddhist nun circuit and the resistance value of low-pressure section 6; Another effect of its equal pressure drag Buddhist nun circuit is that the triggering control section for discharge trigger element 4 in the discharge circuit provides and measures input; All the 3rd effect of pressure drag Buddhist nun circuit is that the discharging current for capacity cell provides damping when discharging gap 3 or lightning arrester 7 action, is reduced in transient state concussion voltage magnitude and frequency that modularization multi-level converter exchanges end or dc terminal appearance.
Trigger control section and be responsible for the triggering control of anti-parallel thyristor element in the discharge circuit.When the power frequency component voltage of the low-pressure section of equal pressure drag Buddhist nun circuit surpasses setup control value (with all pressure drag Buddhist nun circuit high-low pressure part impedance ratio is relevant), show between the end of protective device power-frequency overvoltage to have occurred.The linear quadratic control circuit of discharge circuit provides triggering signal to make its conducting to thyristor, and then short circuit when between the end of realizing whole device after the discharging gap conducting, thereby protection is with this device protected object in parallel when power-frequency overvoltage occurs; When the above-mentioned power frequency component voltage that measures was lower than controlling value, the linear quadratic control circuit stopped the emission of triggering signal, and then recovered the shutoff of discharge trigger element and the normal insulation of discharging gap.
To described modularization multi-level converter excess voltage preventer, its lightning arrester is metal oxide arrester MOA, the switching overvoltage, lightning overvoltage and the steep wave overvoltage that suffer for reducing modularization multi-level converter; When the reference voltage of lightning arrester is U
RefThe time, the preferred value of its switching-surge protective level is the U of 1.5 ~ 1.8p.u
Ref, the preferred value of atmospheric over voltage protection level is the U of 1.8 ~ 2.2p.u.
Ref, the preferred value of steep wave overvoltage protection level is the U of 2.2 ~ 2.5p.u.
Ref
To described modularization multi-level converter excess voltage preventer, it detects the two ends overvoltage that discharging gap 3 in the discharge circuit is detected in the loop by overvoltage, and after satisfying discharging gap 3 time-delay actions triggered gap.
Modularization multi-level converter method of overvoltage protection flow process provided by the invention comprises the steps: as shown in Figure 5
Step 1: the modularization multi-level converter excess voltage preventer is set, excess voltage preventer with individually, two and the above mode that is connected in series or two and the above mode of being connected in parallel be arranged on that modularization multi-level converter exchanges between end and the ground, between dc terminal and the ground, exchanges between holding, between the dc terminal or is arranged at simultaneously above-mentioned position greater than one.
In the step 1, a kind of preferred version of its modularization multi-level converter excess voltage preventer as shown in Figure 4, in its discharge circuit discharging gap and all the high-pressure section of pressure drag Buddhist nun circuit be connected in parallel; The low-pressure section of discharge trigger element and equal pressure drag Buddhist nun circuit is connected in parallel in its discharge circuit.The discharge trigger element comprises antiparallel thyristor and corresponding trigger control circuit.
Step 2: the operation voltage parameter of lightning arrester is set, and the operation voltage parameter of lightning arrester comprises: reference voltage U
Ref, switching-surge protective level SIPL, the horizontal LIPL of atmospheric over voltage protection and steep wave overvoltage protection level STIPL, according to the continuous operating voltage U of modularization multi-level converter
cOr maximum direct current crest voltage PCOV, determine the operation voltage parameter of lightning arrester with reference to standard GB/T 311.1-1997 " insulation coordination of high-tension power transmission and transformation equipment " and power industry standard DL/T 605-1996 " HVDC (High Voltage Direct Current) converter substation insulation coordination guide rule ".Wherein, the unit of each lightning arrestor movement voltage parameter, continuous operating voltage and maximum direct current crest voltage is kV.
Step 3: the operation voltage U that discharge circuit is set
g, the operation voltage of discharge circuit should be according to the expection invasion power-frequency overvoltage level set of modularization multi-level converter, and its unit is kV.
In the step 3, the operation voltage of discharge circuit is the frequency breakdown voltage of its discharging gap, and its representative value is the expection invasion power-frequency overvoltage peak-peak of 0.52 ~ 0.58p.u..
Step 4: the time-delay action of discharge circuit is set, and the time-delay action of discharge circuit is the key of discharge circuit correct operation, and unit is ms, and its representative value is 100 ~ 250ms.
In the step 4; discharging gap should not move after having born operation voltage immediately in the discharge circuit; the strategy that should adopt deferred action described protective device when guaranteeing the discharging gap action suppresses object as power-frequency overvoltage, avoids malfunction under switching overvoltage, lightning overvoltage and steep wave overvoltage.
In the step 4, detect the two ends overvoltage that discharging gap in the discharge circuit is detected in the loop by an overvoltage, simultaneously triggered gap after satisfying the discharging gap time-delay action.
The first execution mode of modularization multi-level converter method of overvoltage protection is as shown in Figure 6 in the embodiment of the invention:
In embodiment 1, the structure of modularization multi-level converter as shown in Figure 1, the inverter inside submodule adopts semi-bridge type sub modular structure shown in Figure 2.This modularization multi-level converter is used for exchanging the 110kV electrical network, and the arrangement of protector provided by the invention as shown in Figure 6.The interchange phase A of modularization multi-level converter over the ground, exchange phase B over the ground with exchanges phase C excess voltage preventer of the present invention is set over the ground, be used for suppressing the relatively overvoltage that interchange is imported into mutually; Simultaneously, the dc terminal P of modularization multi-level converter over the ground and dc terminal N excess voltage preventer of the present invention is set between over the ground, be used for suppressing the end overvoltage to earth that dc terminal is imported into.
In embodiment 1, converter exchanges phase A, exchanges phase B is 64kV with exchanging phase C voltage to earth nominal effective value, and converter dc terminal P and dc terminal N over the ground direct voltage nominal peak are 90kV.Be connected in the continuous operating voltage U of lightning arrester in the protective device that exchanges between the phase and ground
cPeak value is 90kV, is connected in that the maximum direct current crest voltage PCOV of lightning arrester is 90kV in the protective device between dc terminal and the ground.With reference to standard GB/T 311.1-1997 " insulation coordination of high-tension power transmission and transformation equipment " and power industry standard DL/T 605-1996 " HVDC (High Voltage Direct Current) converter substation insulation coordination guide rule "; determine to exchange between the phase and ground in the protective device between each lightning arrester and dc terminal and ground that the switching-surge protective level SIPL of each lightning arrester is 232kV in the protective device; the horizontal LIPL of atmospheric over voltage protection is 290kV, and steep wave overvoltage protection level STIPL is 319kV.
In embodiment 1, be 217kV according to the expection power-frequency overvoltage peak-peak of calculating the invasion modularization multi-level converter.Determine the operation voltage U of discharging gap in the discharge circuit according to the expection invasion power-frequency overvoltage peak-peak of 0.56p.u.
gBe 126kV.
In embodiment 1, the time-delay action that discharging gap in the discharge circuit is set is 200ms.
In embodiment 1, modules multilevel converter excess voltage preventer all comprises discharge circuit, equal pressure drag Buddhist nun circuit and lightning arrester.The N51 end of the N31 end of discharge circuit, equal pressure drag Buddhist nun circuit high-pressure section and the N71 end of lightning arrester link together, and this link are connected in interchange end A, B and C and dc terminal P and the N of modularization multi-level converter.The N62 end of the N42 end of discharge circuit, equal pressure drag Buddhist nun circuit low-pressure section and the N72 end of lightning arrester link together, and this link is connected in the earth.
In embodiment 1, the discharge circuit of modularization multi-level converter excess voltage preventer triggers Thyristors in series by discharging gap and discharge and forms; All pressure drag Buddhist nun circuit is composed in series by high-pressure section and low-pressure section.Wherein, all the high-pressure section of pressure drag Buddhist nun circuit is by resistance and Capacitance parallel connection, and its resistance value is 500k Ω, and capacitance is 40pF; Low-pressure section is by resistance and Capacitance parallel connection, and its resistance value is 50k Ω, and capacitance is 400pF.
In embodiment 1, in the discharge circuit discharging gap be shaped as rod-rod gap, discharging gap is determined according to following formula according to the operation voltage of discharging gap apart from d:
d＝0.1859U
g＝23.4cm ①。
The second execution mode of modularization multi-level converter method of overvoltage protection is as shown in Figure 7 in the embodiment of the invention:
In embodiment 2, the structure of modularization multi-level converter as shown in Figure 1, the inverter inside submodule adopts bridge-type sub modular structure shown in Figure 3.This modularization multi-level converter is used for exchanging the 220kV electrical network, the arrangement of protector provided by the invention as shown in Figure 7, as different from Example 1: the interchange phase A of modularization multi-level converter with exchange between the phase B, exchange phase B and exchanges between the phase C, exchange phase C and excess voltage preventer of the present invention is set with exchanging between the phase A, the alternate overvoltage of importing into mutually for the inhibition interchange; Simultaneously, between the dc terminal P of modularization multi-level converter and dc terminal N, to be connected in series mode two excess voltage preventers provided by the invention are set, to reduce occupation of land and the insulation coordination requirement of single assembly, be used for suppressing overvoltage between end that dc terminal imports into.
In embodiment 2, each modularization multi-level converter excess voltage preventer all comprises discharge circuit, equal pressure drag Buddhist nun circuit and lightning arrester.The N51 end of the N31 end of discharge circuit, equal pressure drag Buddhist nun circuit high-pressure section and the N71 end of lightning arrester link together; The N62 end of the N42 end of discharge circuit, equal pressure drag Buddhist nun circuit low-pressure section and the N72 end of lightning arrester link together.
Should be noted that at last: above embodiment is only in order to illustrate that technical scheme of the present invention is not intended to limit, although with reference to above-described embodiment the present invention is had been described in detail, those of ordinary skill in the field are to be understood that: still can make amendment or be equal to replacement the specific embodiment of the present invention, and do not break away from any modification of spirit and scope of the invention or be equal to replacement, it all should be encompassed in the middle of the claim scope of the present invention.
Claims (13)
1. a modularization multi-level converter method of overvoltage protection is characterized in that, described method comprises the steps:
Step 1: the modularization multi-level converter excess voltage preventer is set: described excess voltage preventer with individually, two and the above mode that is connected in series or two and the above mode of being connected in parallel be arranged on that modularization multi-level converter exchanges between end and the ground, between dc terminal and the ground, exchanges between holding, between the dc terminal or is arranged at simultaneously above-mentioned position greater than one;
Step 2: the operation voltage parameter that lightning arrester is set: the operation voltage parameter of lightning arrester comprises: reference voltage U
Ref, switching-surge protective level SIPL, the horizontal LIPL of atmospheric over voltage protection and steep wave overvoltage protection level STIPL;
Step 3: the operation voltage U that discharge circuit is set
g: the operation voltage of discharge circuit is according to the expection invasion power-frequency overvoltage level set of modularization multi-level converter;
Step 4: the time-delay action that discharge circuit is set.
2. modularization multi-level converter method of overvoltage protection as claimed in claim 1 is characterized in that, in the described step 1, described modularization multi-level converter excess voltage preventer comprises discharge circuit, equal pressure drag Buddhist nun circuit and lightning arrester; Described discharge circuit one end, equal pressure drag Buddhist nun circuit high-pressure section one end are electrically connected with lightning arrester one end is in the same place; The described discharge circuit other end, equal pressure drag Buddhist nun circuit low-pressure section one end are electrically connected with the lightning arrester other end is in the same place;
Discharging gap in the described discharge loop moves when power-frequency overvoltage occurs.
3. modularization multi-level converter method of overvoltage protection as claimed in claim 2, it is characterized in that described equal pressure drag Buddhist nun circuit is used for: the voltage that discharge circuit discharging gap and discharge trigger element are born distributes by the high-pressure section of equal pressure drag Buddhist nun circuit and the resistance value of low-pressure section; 2) the triggering control section for discharge trigger element in the discharge circuit provides the measurement input; 3) discharging current for capacity cell provides damping when discharging gap or lightning arrestor movement.
4. modularization multi-level converter method of overvoltage protection as claimed in claim 2, it is characterized in that, described lightning arrester is metal oxide arrester, the switching overvoltage, lightning overvoltage and the steep wave overvoltage that suffer for reducing modularization multi-level converter; When the reference voltage of lightning arrester is U
RefThe time, the preferred value of the switching-surge protective level of lightning arrester is the U of 1.5 ~ 1.8p.u.
Ref, the preferred value of atmospheric over voltage protection level is the U of 1.8 ~ 2.2p.u
Ref, the preferred value of steep wave overvoltage protection level is the U of 2.2 ~ 2.5p.u.
Ref
5. modularization multi-level converter method of overvoltage protection as claimed in claim 1 is characterized in that, in the described step 2, according to the continuous operating voltage U of modularization multi-level converter
cOr maximum direct current crest voltage PCOV, determine the operation voltage parameter of lightning arrester with reference to standard GB/T 311.1-1997 " insulation coordination of high-tension power transmission and transformation equipment " and power industry standard DL/T 605-1996 " HVDC (High Voltage Direct Current) converter substation insulation coordination guide rule "; The unit of described lightning arrestor movement voltage parameter, continuous operating voltage and maximum direct current crest voltage is kV.
6. modularization multi-level converter method of overvoltage protection as claimed in claim 1 is characterized in that, in the described step 3, and the operation voltage U of discharge circuit
gBe the frequency breakdown voltage of its discharging gap, unit is kV, and its value is the expection invasion power-frequency overvoltage peak-peak of 0.52 ~ 0.58p.u..
7. modularization multi-level converter method of overvoltage protection as claimed in claim 1 is characterized in that, in the described step 4, the discharging gap in the discharge circuit is bearing operation voltage U
gMove through behind the time-delay action, time-delay action unit is ms again, and its value is 100 ~ 250ms.
8. a modularization multi-level converter excess voltage preventer is characterized in that, described excess voltage preventer comprises discharge circuit, equal pressure drag Buddhist nun circuit and lightning arrester; Described discharge circuit one end, equal pressure drag Buddhist nun circuit high-pressure section one end are electrically connected with lightning arrester one end is in the same place; The described discharge circuit other end, equal pressure drag Buddhist nun circuit low-pressure section one end are electrically connected with the lightning arrester other end is in the same place;
Described excess voltage preventer with individually, be connected in series that mode or the mode of being connected in parallel are arranged on that modularization multi-level converter exchanges between end and the ground, between dc terminal and the ground, exchanges between holding, between the dc terminal or is arranged at simultaneously above-mentioned position greater than one.
9. modularization multi-level converter excess voltage preventer as claimed in claim 8 is characterized in that, described discharge circuit is composed in series by discharging gap and discharge trigger element; Described discharge trigger element is comprised of two antiparallel thyristors; Described equal pressure drag Buddhist nun circuit is composed in series by high-pressure section and low-pressure section, and the high-pressure section of described equal pressure drag Buddhist nun circuit and low-pressure section all have three kinds of forms, comprising: resistance and Capacitance parallel connection, resistance and capacitances in series, single resistance.
10. modularization multi-level converter excess voltage preventer as claimed in claim 8 is characterized in that, described discharging gap be shaped as rod-rod gap, discharging gap apart from d according to the operation voltage of discharging gap according to d=0.1859U
gDetermine that discharging gap is cm apart from the unit of d.
11. modularization multi-level converter excess voltage preventer as claimed in claim 8 is characterized in that, described discharging gap is bearing operation voltage U
gAnd move behind the process time-delay action, time-delay action unit is ms, its value is 100 ~ 250ms.
12. the modularization multi-level converter excess voltage preventer is characterized in that as claimed in claim 8 or 9, and the high-pressure section of discharging gap in the discharge circuit with equal pressure drag Buddhist nun circuit is connected in parallel; The low-pressure section of discharge trigger element in the discharge circuit and equal pressure drag Buddhist nun circuit is connected in parallel; Capacitor C in its equal pressure drag Buddhist nun circuit
1And C
2Value be 300 ~ 8000pF, resistor R
1And R
2Value be 50 ~ 600k Ω, resistor parameter and capacitor parameters satisfy: R
1C
1=R
2C
2
13. modularization multi-level converter excess voltage preventer as claimed in claim 8, it is characterized in that, described lightning arrester is metal oxide arrester, the switching overvoltage, lightning overvoltage and the steep wave overvoltage that suffer for reducing modularization multi-level converter; When the reference voltage of lightning arrester is U
RefThe time, the preferred value of the switching-surge protective level of lightning arrester is the U of 1.5 ~ 1.8p.u
Ref, the preferred value of atmospheric over voltage protection level is the U of 1.8 ~ 2.2p.u
Ref, the preferred value of steep wave overvoltage protection level is the U of 2.2 ~ 2.5p.u
Ref
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104467393A (en) * | 2015-01-04 | 2015-03-25 | 南京南瑞继保电气有限公司 | Device for preventing sub-module capacitor overvoltage |
| CN108879637A (en) * | 2018-08-03 | 2018-11-23 | 南京南瑞继保电气有限公司 | Mixed DC high-low pressure inverter connects arrester Parameters design at bus |
| WO2019020186A1 (en) * | 2017-07-27 | 2019-01-31 | Siemens Aktiengesellschaft | Converter arrangement having phase module arrester and method for short-circuit protection thereof |
| CN110932225A (en) * | 2019-10-29 | 2020-03-27 | 中国电力科学研究院有限公司 | Setting method and setting device for overvoltage protection of ultra/extra-high voltage alternating current circuit |
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| WO2019020195A1 (en) * | 2017-07-28 | 2019-01-31 | Siemens Aktiengesellschaft | Impedor for ac fault current handling in an hvdc transmission converter |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05122844A (en) * | 1991-10-25 | 1993-05-18 | Ngk Insulators Ltd | Semiconductor arrester |
| CN1584607A (en) * | 2004-05-31 | 2005-02-23 | 席世友 | Overvoltage on-line sampler for 6-35 KV electric power system |
| CN101178429A (en) * | 2007-11-06 | 2008-05-14 | 中国电力科学研究院 | Electric potential displace method based on gate circuit transistor gate control |
-
2012
- 2012-12-12 CN CN201210537285.3A patent/CN103066582B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05122844A (en) * | 1991-10-25 | 1993-05-18 | Ngk Insulators Ltd | Semiconductor arrester |
| CN1584607A (en) * | 2004-05-31 | 2005-02-23 | 席世友 | Overvoltage on-line sampler for 6-35 KV electric power system |
| CN101178429A (en) * | 2007-11-06 | 2008-05-14 | 中国电力科学研究院 | Electric potential displace method based on gate circuit transistor gate control |
Non-Patent Citations (2)
| Title |
|---|
| 周浩等: "±1100kV特高压直流换流站过电压保护和绝缘配合", 《电网技术》, vol. 36, no. 9, 30 September 2012 (2012-09-30), pages 1 - 8 * |
| 聂定珍等: "锦屏-苏南特高压直流输电工程换流站绝缘配合", 《高电压技术》, vol. 36, no. 1, 31 January 2010 (2010-01-31), pages 92 - 97 * |
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| CN104467393A (en) * | 2015-01-04 | 2015-03-25 | 南京南瑞继保电气有限公司 | Device for preventing sub-module capacitor overvoltage |
| WO2016107616A1 (en) * | 2015-01-04 | 2016-07-07 | 南京南瑞继保电气有限公司 | Apparatus for preventing capacitance overvoltage in voltage-source type inverter |
| WO2019020186A1 (en) * | 2017-07-27 | 2019-01-31 | Siemens Aktiengesellschaft | Converter arrangement having phase module arrester and method for short-circuit protection thereof |
| CN110999064A (en) * | 2017-07-27 | 2020-04-10 | 西门子股份公司 | Converter arrangement with phase module arresters and method for short-circuit protection thereof |
| US11159094B2 (en) | 2017-07-27 | 2021-10-26 | Siemens Energy Global GmbH & Co. KG | Converter arrangement having a phase module arrester and method for short-circuit protection thereof |
| CN110999064B (en) * | 2017-07-27 | 2023-06-16 | 西门子能源全球有限公司 | Converter device with phase module discharger and method for short-circuit protection thereof |
| CN108879637A (en) * | 2018-08-03 | 2018-11-23 | 南京南瑞继保电气有限公司 | Mixed DC high-low pressure inverter connects arrester Parameters design at bus |
| CN110932225A (en) * | 2019-10-29 | 2020-03-27 | 中国电力科学研究院有限公司 | Setting method and setting device for overvoltage protection of ultra/extra-high voltage alternating current circuit |
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