CN205960989U - Supplementary centralized half -bridge of electric capacity / single clamp series -parallel connection MMC is from voltage -sharing topology based on inequality constraint - Google Patents

Abstract

The utility model provides a supplementary centralized half -bridge of electric capacity / single clamp series -parallel connection MMC is from voltage -sharing topology based on inequality constraint. Half -bridge / single clamp series -parallel connection MMC in the voltage -sharing topology, half -bridge / single clamp series -parallel connection MMC model with in the voltage -sharing auxiliary circuit passes through the auxiliary circuit 6 (i) (i) electric contact takes place to N for auxiliary switch, and auxiliary switch is closed, and both constitute supplementary centralized half -bridge of electric capacity / single clamp series -parallel connection MMC is from voltage -sharing topology based on inequality constraint, and auxiliary switch opens, and it is topological that the topoligical equivalence be half -bridge / single clamp series -parallel connection MMC. Do not stressing under two kinds of topology difference's the condition that (i) (i) a mechanical switch can leave out K 6 among the auxiliary switch. This half -bridge / single clamp series -parallel connection MMC is from voltage -sharing topology, can clamp direct current side trouble, do not rely on special voltage -sharing control simultaneously, can accomplish directly exchange the basis of energy conversion on, realize the equilibrium of submodule piece capacitance voltage spontaneously, can make with electric capacity appearance value, realization MMC's base frequency by corresponding reductions submodule piece triggering frequency in addition.

Description

The centralized half-bridge of auxiliary capacitor based on inequality constraints/mono- clamp series-parallel connection MMC is from all Pressure topology

Technical field

The utility model is related to flexible transmission field and in particular to a kind of auxiliary capacitor based on inequality constraints is centralized Half-bridge/mono- clamp series-parallel connection MMC is topological from all pressing.

Background technology

Modularization multi-level converter MMC is the developing direction of following HVDC Transmission Technology, and MMC adopts submodule (Sub- Module, SM) mode that cascades constructs converter valve, it is to avoid the direct series connection of big metering device, reduce conforming to device Require, simultaneously facilitate dilatation and redundant configuration.With the rising of level number, output waveform, close to sinusoidal, can effectively avoid low electricity The defect of flat VSC-HVDC.

Half-bridge/mono- clamp series-parallel connection MMC is combined by half-bridge submodule and single clamp submodule.Half-bridge submodule is by 2 IGBT module, 1 sub- module capacitance, 1 IGCT and 1 mechanical switch are constituted；Single clamp submodule by 3 IGBT module, 1 Individual sub- module capacitance, a diode and 1 mechanical switch are constituted.This series-parallel connection MMC, low cost, running wastage is little, simultaneously can pincers Position DC side fault.

Different from two level, three level VSC, the DC voltage of half-bridge/mono- clamp series-parallel connection MMC is not by a bulky capacitor Support, but supported by a series of separate suspension submodule capacitances in series.In order to ensure the ripple of AC voltage output In form quality amount and guarantee module, each power semiconductor bears identical stress, supports DC voltage also for more preferable, subtracts Little alternate circulation, it is necessary to assure submodule capacitor voltage is in the state of dynamic stability in the periodicity flowing of brachium pontis power.

All pressing algorithm based on the sequence of capacitance voltage sequence is to solve half-bridge/mono- clamp series-parallel connection MMC Neutron module electricity at present Hold the main flow thinking of electric voltage equalization problem.But, the realization of ranking function has to rely on the Millisecond sampling of capacitance voltage, needs Substantial amounts of sensor and optical-fibre channel are coordinated；Secondly, when group number of modules increases, the operand of capacitance voltage sequence Rapid increase, is that the hardware design of controller brings huge challenge；Additionally, sequence all presses the realization of algorithm that submodule is cut-off Frequency has very high requirement, cut-offs frequency and is closely related with voltage equalizing, in practice process, probably due to the limit of voltage equalizing System is it has to improve the triggering frequency of submodule, and then brings the increase of transverter loss.

Document " A DC-Link Voltage Self-Balance Method for a Diode-Clamped Modular Multilevel Converter With Minimum Number of Voltage Sensors " is it is proposed that one Plant and rely on clamp diode and transformer to realize MMC submodule capacitor voltage thinking in a balanced way.But the program in design Determine the modular nature that degree destroys submodule, submodule capacitive energy interchange channel is also confined in phase, could not be fully sharp With the existing structure of MMC, the introducing of three transformers also brings along larger being transformed into while so that control strategy is complicated This.

Utility model content

For the problems referred to above, the purpose of this utility model is to propose a kind of economy, modular, is independent of all pressing calculation Method, can accordingly reduce submodule simultaneously and trigger frequency and capacitor's capacity and have half-bridge/mono- clamp of DC Line Fault clamping ability Series-parallel connection MMC is topological from all pressing.

The specific constituted mode of the utility model is as follows.

The centralized half-bridge of auxiliary capacitor based on inequality constraints/mono- clamp series-parallel connection MMC from all press topology, including by A, B, C three-phase constitute half-bridge MMC model, each brachium pontis of A, B, C three-phase respectively byKIndividual half-bridge submodule,N-KIndividual single clamp Module and 1 brachium pontis reactor are in series；Including by 6NIndividual auxiliary switch（6KIndividual mechanical switch, 6N-6KIndividual IGBT mould Block）, 6N+ 7 clamp diodes, 4 auxiliary capacitors, 2 auxiliary IGBT module composition from all press subsidiary loop.

Centralized half-bridge/mono- clamp series-parallel connection the MMC of the above-mentioned auxiliary capacitor based on inequality constraints is from all pressing topology, series-parallel connection In MMC model, A phase upper and lower bridge arm, in single clamp submodule, diode connexon module capacitance positive pole, IGBT module connexon Module capacitance negative pole.1st submodule of brachium pontis in A phase, its submodule electric capacity negative pole the 2nd son with brachium pontis in A phase downwards Module I GBT module midpoint is connected, and its submodule IGBT module midpoint is connected with dc bus positive pole upwards；Bridge in A phase The of armiIndividual submodule, whereiniValue be 2～K- 1, its submodule electric capacity negative pole downwards with brachium pontis in A phase thei+ 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint upwards with brachium pontis in A phasei- 1 submodule Block electric capacity negative pole is connected；The of brachium pontis in A phaseKIndividual half-bridge submodule, its submodule electric capacity negative pole downwards with brachium pontis in A phase ?K+ 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint upwards with brachium pontis in A phaseK- 1 sub- module capacitance negative pole is connected；The of brachium pontis in A phasejIndividual submodule, whereinjValue beK+ 2～N- 1, its son Module diode and IGBT module tie-point brachium pontis the downwards and in A phasej+ 1 sub- module I GBT module midpoint is connected, its Submodule IGBT module midpoint upwards with brachium pontis in A phasej- 1 submodule diode is connected with IGBT module tie-point Connect；Brachium pontis in A phaseNIndividual submodule, its submodule diode and IGBT module tie-point are down through two brachium pontis reactorsL ₀ Module I GBT module midpoint sub- with the 1st of brachium pontis under A phase is connected, its submodule IGBT module midpoint upwards with bridge in A phase The of armN- 1 submodule diode is connected with IGBT module tie-point；The of brachium pontis under A phaseiIndividual submodule, whereini Value be 2～K- 1, its submodule electric capacity negative pole downwards with brachium pontis under A phase thei+ 1 sub- module I GBT module midpoint is connected Connect, its IGBT module midpoint upwards with brachium pontis under A phasei- 1 sub- module capacitance negative pole is connected；The of brachium pontis under A phaseK Individual submodule, its submodule electric capacity negative pole downwards with brachium pontis under A phase theK+ 1 sub- module I GBT module midpoint is connected, its Submodule IGBT module midpoint upwards with brachium pontis under A phaseK- 1 sub- module capacitance negative pole is connected；Brachium pontis under A phasejIndividual Submodule, whereinjValue beK+ 2～N- 1, its submodule diode and IGBT module tie-point brachium pontis downwards and under A phase Thej+ 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint upwards with brachium pontis under A phasej- 1 Submodule diode is connected with IGBT module tie-point；Brachium pontis under A phaseNIndividual submodule diode is connect with IGBT module Point is connected with dc bus negative pole downwards, its submodule IGBT module midpoint upwards with brachium pontis under A phase theN- 1 submodule Block diode is connected with IGBT module tie-point.B phase upper and lower bridge arm, in single clamp submodule, IGBT module connects submodule Capacitance cathode, diode connexon module capacitance negative pole, the 1st submodule of upper brachium pontis, its submodule capacitance cathode upwards with Dc bus positive pole is connected, its submodule IGBT module midpoint module capacitance positive pole phase sub- with the 2nd of brachium pontis in B phase downwards Connect；The of brachium pontis in B phaseiIndividual submodule, whereiniValue be 2～K- 1, its submodule capacitance cathode upwards with B phase The of upper brachium pontisi- 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint downwards with brachium pontis in B phase ?i+ 1 sub- module capacitance positive pole is connected；The of brachium pontis in B phaseKIndividual submodule, its submodule capacitance cathode upwards with The of brachium pontis in B phaseK- 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint downwards with bridge in B phase ArmK+ 1 sub- module I GBT module is connected with diode connection point；The of brachium pontis in B phasejIndividual submodule, whereinj's Value isK+ 2～N- 1, its submodule IGBT module and diode connection point upwards with brachium pontis in B phasej- 1 submodule IGBT module midpoint is connected, its submodule IGBT module midpoint downwards with brachium pontis in B phase thej+ 1 sub- module I GBT module It is connected with diode connection point；Brachium pontis in B phaseNIndividual submodule, its submodule IGBT module is with diode connection point upwards With brachium pontis in B phaseN- 1 sub- module I GBT module midpoint is connected, and its submodule IGBT module midpoint is down through two bridges Arm reactorL ₀It is connected with the 1st sub- module capacitance positive pole of brachium pontis under B phase；The of brachium pontis under B phaseiIndividual submodule, whereiniValue be 2～K- 1, its submodule capacitance cathode upwards with brachium pontis under B phasei- 1 sub- module I GBT module midpoint Be connected, its submodule IGBT module midpoint downwards with brachium pontis under B phase thei+ 1 sub- module capacitance positive pole is connected；B phase The of lower brachium pontisKIndividual submodule, its submodule capacitance cathode upwards with brachium pontis under B phaseKIn -1 sub- module I GBT module Point is connected, its submodule IGBT module midpoint downwards with brachium pontis under B phase theK+ 1 sub- module I GBT module is joined with diode Node is connected；Brachium pontis under B phasejIndividual submodule, whereinjValue beK+ 2～N- 1, its submodule IGBT module with Diode connection point upwards with brachium pontis under B phasej- 1 sub- module I GBT module midpoint is connected, its submodule IGBT module Midpoint downwards with brachium pontis under B phase thej+ 1 sub- module I GBT module is connected with diode connection point；Brachium pontis under B phaseNIndividual Submodule, its submodule IGBT module and diode connection point upwards with brachium pontis under B phaseNIn -1 sub- module I GBT module Point is connected, and its submodule IGBT module midpoint is connected with dc bus negative pole downwards.The connection of C phase upper and lower bridge arm submodule Mode is consistent with A phase or B.

Centralized half-bridge/mono- clamp series-parallel connection the MMC of the above-mentioned auxiliary capacitor based on inequality constraints from all pressing topology, from all pressing In subsidiary loop, first auxiliary capacitor is in parallel by clamp diode with second auxiliary capacitor, and second auxiliary capacitor is just Pole connects first auxiliary capacitor negative pole connection clamp diode of auxiliary IGBT module and is incorporated to dc bus positive pole；3rd auxiliary Electric capacity is in parallel by clamp diode with the 4th auxiliary capacitor, and the 3rd auxiliary capacitor negative pole connects auxiliary IGBT module the 4th Individual auxiliary capacitor positive pole connects clamp diode and is incorporated to dc bus negative pole.Clamp diode, is connected in A phase by auxiliary switch 1st sub- module capacitance and first auxiliary capacitor positive pole in brachium pontis；Connect in A phase in brachium pontis the by auxiliary switchiHeight Module capacitance and thei+ 1 sub- module capacitance positive pole, whereiniValue be 1～N-1；Connected in A phase by auxiliary switch In brachium pontisNThe 1st sub- module capacitance positive pole of individual sub- module capacitance and brachium pontis under A phase；Bridge under A phase is connected by auxiliary switch In armiIndividual sub- module capacitance and brachium pontis under A phasei+ 1 sub- module capacitance positive pole, whereiniValue be 1～N-1； Connect under A phase in brachium pontis the by auxiliary switchNIndividual sub- module capacitance and the 3rd auxiliary capacitor positive pole.Clamp diode, leads to Cross the negative pole that auxiliary switch connects the 1st sub- module capacitance and second auxiliary capacitor in brachium pontis in B phase；By auxiliary switch even Connect in brachium pontis in B phaseiIndividual sub- module capacitance and theiThe negative pole of+1 sub- module capacitance, whereiniValue be 1～N- 1；Connect in B phase in brachium pontis the by auxiliary switchNThe 1st sub- module capacitance of individual sub- module capacitance and brachium pontis under B phase negative Pole；Connect under B phase in brachium pontis the by auxiliary switchiIndividual sub- module capacitance and brachium pontis under B phasei+ 1 sub- module capacitance Negative pole, whereiniValue be 1～N-1；Connect under B phase in brachium pontis the by auxiliary switchNIndividual sub- module capacitance and the 4th The negative pole of individual auxiliary capacitor.The annexation of C phase clamp diode is corresponding with the annexation of its submodule.

Brief description

Fig. 1 is the structural representation of half-bridge submodule；

Fig. 2 is single structural representation clamping submodule；

Fig. 3 is that the centralized half-bridge of the auxiliary capacitor/mono- clamp series-parallel connection MMC based on inequality constraints is topological from all pressing.

Specific embodiment

For of the present utility model performance and operation principle are expanded on further, below in conjunction with accompanying drawing to the composition to utility model Mode is specifically described with operation principle.But the half-bridge based on this principle/mono- clamp series-parallel connection MMC is not limited to figure from all pressure topologys 3.

With reference to Fig. 3, the centralized half-bridge of the auxiliary capacitor based on inequality constraints/mono- clamp series-parallel connection MMC, from all pressing topology, wraps Include the half-bridge that is made up of A, B, C three-phase/mono- clamp series-parallel connection MMC model, each brachium pontis of A, B, C three-phase respectively byKIndividual half-bridge submodule Block,N-KIndividual single clamp submodule and 1 brachium pontis reactor are in series；Including by 6NIndividual auxiliary switch（6KIndividual machinery is opened Close, 6N-6KIndividual IGBT module）, 6N+ 7 clamp diodes, 4 auxiliary capacitors, 2 assist the certainly equal of IGBT module composition Pressure subsidiary loop.

In half-bridge/mono- clamp series-parallel connection MMC model, A phase upper and lower bridge arm, in single clamp submodule, diode connects submodule Capacitance cathode, IGBT module connexon module capacitance negative pole.1st submodule of brachium pontis, its submodule electric capacity in A phaseC _{au­_1} Downwards module I GBT module midpoint sub- with the 2nd of brachium pontis in A phase is connected negative pole, its submodule IGBT module midpoint upwards with Dc bus positive pole is connected；The of brachium pontis in A phaseiIndividual submodule, whereiniValue be 2～K- 1, its submodule electricity HoldC _{au­_i} Negative pole downwards with brachium pontis in A phase thei+ 1 sub- module I GBT module midpoint is connected, its submodule IGBT mould Block midpoint upwards with brachium pontis in A phasei- 1 sub- module capacitanceC _{au­_i-1}Negative pole is connected；The of brachium pontis in A phaseKIndividual Half-bridge submodule, its submodule electric capacityC _{au­_K} Negative pole downwards with brachium pontis in A phase theK+ 1 sub- module I GBT module midpoint phase Connect, its submodule IGBT module midpoint upwards with brachium pontis in A phase theK- 1 sub- module capacitanceC _{au­_K-1}Negative pole is connected Connect；The of brachium pontis in A phasejIndividual submodule, whereinjValue beK+ 2～N- 1, its submodule diode and IGBT module Tie-point downwards with brachium pontis in A phase thej+ 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint to Upper the with brachium pontis in A phasej- 1 submodule diode is connected with IGBT module tie-point；Brachium pontis in A phaseNIndividual submodule Block, its submodule diode and IGBT module tie-point are down through two brachium pontis reactorsL ₀The 1st submodule with brachium pontis under A phase Block IGBT module midpoint is connected, its submodule IGBT module midpoint upwards with brachium pontis in A phaseN- 1 submodule two pole Pipe is connected with IGBT module tie-point；The of brachium pontis under A phaseiIndividual submodule, whereiniValue be 2～K- 1, its submodule Block electric capacityC _{al­_i} Negative pole downwards with brachium pontis under A phase thei+ 1 sub- module I GBT module midpoint is connected, in its IGBT module Point upwards with brachium pontis under A phase thei- 1 sub- module capacitanceC _{al­_i-1}Negative pole is connected；The of brachium pontis under A phaseKIndividual submodule, Its submodule electric capacityC _{al_K} Negative pole downwards with brachium pontis under A phase theK+ 1 sub- module I GBT module midpoint is connected, its submodule Block IGBT module midpoint upwards with brachium pontis under A phaseK- 1 sub- module capacitanceC _{al­_K-1}Negative pole is connected；Brachium pontis under A phasej Individual submodule, whereinjValue beK+ 2～N- 1, its submodule diode and IGBT module tie-point bridge downwards and under A phase Armj+ 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint upwards with brachium pontis under A phasej-1 Individual submodule diode is connected with IGBT module tie-point；Brachium pontis under A phaseNIndividual submodule diode is joined with IGBT module Node is connected with dc bus negative pole downwards, its submodule IGBT module midpoint upwards with brachium pontis under A phaseN- 1 son Module diode is connected with IGBT module tie-point.B phase upper and lower bridge arm, in single clamp submodule, IGBT module connects submodule Block capacitance cathode, diode connexon module capacitance negative pole, the 1st submodule of upper brachium pontis, its submodule electric capacityC _{bu­_1}Positive pole It is connected with dc bus positive pole upwards, its submodule IGBT module midpoint the 2nd sub- module capacitance with brachium pontis in B phase downwardsC _{bu­_2}Positive pole is connected；The of brachium pontis in B phaseiIndividual submodule, whereiniValue be 2～K- 1, its submodule electric capacityC _{bu­_i} Positive pole upwards with brachium pontis in B phasei- 1 sub- module I GBT module midpoint is connected, in its submodule IGBT module Point downwards with brachium pontis in B phase thei+ 1 sub- module capacitanceC _{bu­_i+1}Positive pole is connected；The of brachium pontis in B phaseKIndividual submodule Block, its submodule electric capacityC _{bu­_K} Positive pole upwards with brachium pontis in B phaseK- 1 sub- module I GBT module midpoint is connected, its Submodule IGBT module midpoint downwards with brachium pontis in B phase theK+ 1 sub- module I GBT module is connected with diode connection point；B The of brachium pontis in phasejIndividual submodule, whereinjValue beK+ 2～N- 1, its submodule IGBT module and diode connection Point upwards with brachium pontis in B phase thej- 1 sub- module I GBT module midpoint is connected, and its submodule IGBT module midpoint is downwards and B Brachium pontis in phasej+ 1 sub- module I GBT module is connected with diode connection point；Brachium pontis in B phaseNIndividual submodule, its son Module I GBT module and diode connection point upwards with brachium pontis in B phaseN- 1 sub- module I GBT module midpoint is connected, its Submodule IGBT module midpoint is down through two brachium pontis reactorsL ₀The 1st sub- module capacitance with brachium pontis under B phaseC _{bl­_1}Positive pole It is connected；The of brachium pontis under B phaseiIndividual submodule, whereiniValue be 2～K- 1, its submodule electric capacityC _{bl_i} Positive pole to Upper with brachium pontis under B phase thei- 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint downwards with B phase The of lower brachium pontisi+ 1 sub- module capacitanceC _{bl­_i+1}Positive pole is connected；The of brachium pontis under B phaseKIndividual submodule, its submodule Electric capacityC _{bl_K} Positive pole upwards with brachium pontis under B phaseK- 1 sub- module I GBT module midpoint is connected, its submodule IGBT module Midpoint downwards with brachium pontis under B phase theK+ 1 sub- module I GBT module is connected with diode connection point；Brachium pontis under B phasejIndividual Submodule, whereinjValue beK+ 2～N- 1, its submodule IGBT module and diode connection point upwards with brachium pontis under B phase Thej- 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint downwards with brachium pontis under B phase thej+ 1 Submodule IGBT module is connected with diode connection point；Brachium pontis under B phaseNIndividual submodule, its submodule IGBT module and two Pole pipe tie-point upwards with brachium pontis under B phaseN- 1 sub- module I GBT module midpoint is connected, in its submodule IGBT module Point is connected with dc bus negative pole downwards.The connected mode of C phase upper and lower bridge arm submodule is consistent with A.

From all pressing in subsidiary loop, auxiliary capacitorC ₁With auxiliary capacitorC ₂In parallel, the auxiliary capacitor by clamp diodeC ₂ Positive pole connects auxiliary IGBT moduleT ₁, auxiliary capacitorC ₁Negative pole connects clamp diode and is incorporated to dc bus positive pole；Auxiliary capacitorC ₃With auxiliary capacitorC ₄In parallel, the auxiliary capacitor by clamp diodeC ₃Negative pole connects auxiliary IGBT moduleT ₂, auxiliary capacitorC ₄Positive pole connects clamp diode and is incorporated to dc bus negative pole.Clamp diode, by auxiliary switchK _{au_12}Connect bridge in A phase 1st sub- module capacitance in armC _{au­_1}With auxiliary capacitorC ₁Positive pole；By auxiliary switchK _{au_i2}、K _{au_（i+1）2}Connect in A phase In brachium pontisiIndividual sub- module capacitanceC _{au­_i} Withi+ 1 sub- module capacitanceC _{au­_i+1}Positive pole, whereiniValue be 1 ~K-1；By auxiliary switchK _{au_K2}、T _{au_K+1}Connect in A phase in brachium pontis theKIndividual sub- module capacitanceC _{au­_K} WithK+ 1 Submodule electric capacityC _{au_K+1}Positive pole；By auxiliary switchT _{au_j} 、T _{au_j+1}Connect in A phase in brachium pontis thejIndividual sub- module capacitanceC _{au­_j} Withj+ 1 sub- module capacitanceC _{au­_j+1}Positive pole, whereinjValue beK+ 1～N-1；By auxiliary switchT _{au_N} 、K _{al_12}Connect in A phase in brachium pontis theNIndividual sub- module capacitanceC _{au_N} With the 1st sub- module capacitance of brachium pontis under A phaseC _{al­_1} Positive pole；By auxiliary switchK _{al_i2}、K _{al_（i+1）2}Connect under A phase in brachium pontis theiIndividual sub- module capacitanceC _{al­_i} Withi+ 1 Submodule electric capacityC _{al­_i+1}Positive pole, whereiniValue be 1～K-1；By auxiliary switchK _{al_K2}、T _{al_K+1}Connect A phase In lower brachium pontisKIndividual sub- module capacitanceC _{al­_K} WithK+ 1 sub- module capacitanceC _{al­_K+1}Positive pole；By auxiliary switchT _{al_j} 、T _{al_j+1}Connect under A phase in brachium pontis thejIndividual sub- module capacitanceC _{al_j} Withj+ 1 sub- module capacitanceC _{al­_j+1}Just Pole, whereinjValue beK+ 1～N-1；By auxiliary switchT _{al_N} Connect under A phase in brachium pontis theNIndividual sub- module capacitanceC _{al_N} With auxiliary capacitorC ₃Positive pole.Clamp diode, by auxiliary switchK _{bu_12}Connect the 1st submodule in brachium pontis in B phase Electric capacityC _{bu­_1}With auxiliary capacitorC ₂Negative pole；By auxiliary switchK _{bu_i2}、K _{bu_（i+1）2}Connect in B phase in brachium pontis theiIndividual submodule Block electric capacityC _{bu­_i} Withi+ 1 sub- module capacitanceC _{bu­_i+1}Negative pole, whereiniValue be 1～K-1；By auxiliary switchK _{bu_K2}、T _{bu_K+1}Connect in B phase in brachium pontis theKIndividual sub- module capacitanceC _{bu­_K} WithK+ 1 sub- module capacitanceC _{bu­_K+1}Negative Pole；By auxiliary switchT _{bu_j} 、T _{bu_j+1}Connect in B phase in brachium pontis thejIndividual sub- module capacitanceC _{bu­_j} Withj+ 1 submodule Block electric capacityC _{bu­_j+1}Negative pole, whereinjValue beK+ 1～N-1；By auxiliary switchT _{bu_N} 、K _{bl_12}Connect bridge in B phase In armNIndividual sub- module capacitanceC _{bu­_N} With the 1st sub- module capacitance in brachium pontis under B phaseC _{bl_1}Negative pole；By auxiliary switchK _{bl_i2}、K _{bl_（i+1）2}Connect under B phase in brachium pontis theiIndividual sub- module capacitanceC _{bl­_i} Withi+ 1 sub- module capacitanceC _{bl­_i+1} Negative pole, whereiniValue be 1～K-1；By auxiliary switchK _{bl_K2}、T _{bl_K+1}Connect under B phase in brachium pontis theKIndividual submodule Block electric capacityC _{bl_K} WithK+ 1 sub- module capacitanceC _{bl­_K+1}Negative pole；By auxiliary switchT _{bl_j} 、T _{bl_j+1}Connect bridge under B phase In armjIndividual sub- module capacitanceC _{bl­_j} Withj+ 1 sub- module capacitanceC _{bl_j+1}Negative pole, whereinjValue beK+ 1～N -1；By auxiliary switchT _{bl_N} Connect under B phase in brachium pontis theNIndividual sub- module capacitanceC _{bl­_N} With auxiliary capacitorC ₄Negative pole.C phase The annexation of clamp diode is consistent with A.

Under normal circumstances, from all pressure subsidiary loops 6NIndividual auxiliary switchK _{au_i2}、K _{al_i2}、K _{bu_i2}、K _{bl_i2}、K _{cu_i2}、K _{cl_i2}、T _{au_j} 、T _{al_j} 、T _{bu_j} 、T _{bl_j} 、T _{cu_j} 、T _{cl_j} Normally closed, whereiniValue be 1～K,jValue ForK+ 1～N, first sub- module capacitance of brachium pontis in A phaseC _{au­_1}During bypass, now assist IGBT moduleT ₁Disconnect, submodule Block electric capacityC _{au­_1}With auxiliary capacitorC ₁In parallel by clamp diode；Brachium pontis in A phaseiIndividual sub- module capacitanceC _{au­_i} Bypass When, whereiniValue be 2～N, submodule electric capacityC _{au­_i} With submodule electric capacityC _{au­_i-1}In parallel by clamp diode；A First sub- module capacitance of brachium pontis under phaseC _{al_1}During bypass, submodule electric capacityC _{al­_1}By clamp diode, two brachium pontis reactance DeviceL ₀With submodule electric capacityC _{au­_N} In parallel；Brachium pontis under A phaseiIndividual sub- module capacitanceC _{al_i} During bypass, whereiniValue be 2～N, submodule electric capacityC _{al­_i} With submodule electric capacityC _{al_i-1}In parallel by clamp diode；Auxiliary IGBT moduleT ₂Closure When, auxiliary capacitorC ₃By clamp diode and submodule electric capacityC _{al_N} In parallel.

Under normal circumstances, from all pressure subsidiary loops 6NIndividual auxiliary switchK _{au_i2}、K _{al_i2}、K _{bu_i2}、K _{bl_i2}、K _{cu_i2}、K _{cl_i2}、T _{au_j} 、T _{al_j} 、T _{bu_j} 、T _{bl_j} 、T _{cu_j} 、T _{cl_j} Normally closed, whereiniValue be 1～K,jValue ForK+ 1～N, assist IGBT moduleT ₁During closure, auxiliary capacitorC ₂With submodule electric capacityC _{bu­_1}By clamp diode simultaneously Connection；Brachium pontis in B phaseiIndividual sub- module capacitanceC _{bu­_i} During bypass, whereiniValue be 1～N- 1, submodule electric capacityC _{bu­_i} With submodule electric capacityC _{bu­_i+1}In parallel by clamp diode；Brachium pontis in B phaseNIndividual sub- module capacitanceC _{bu_N} During bypass, son Module capacitanceC _{bu­_N} By clamp diode, two brachium pontis reactorsL ₀With submodule electric capacityC _{bl­_1}In parallel；Brachium pontis under B phaseiIndividual sub- module capacitanceC _{bl_i} During bypass, whereiniValue be 1～N- 1, submodule electric capacityC _{bl­_i} With submodule electric capacityC _{bl_i+1}In parallel by clamp diode；Brachium pontis under B phaseNIndividual sub- module capacitanceC _{bl_N} During bypass, submodule electric capacityC _{bl­_N} With auxiliary capacitorC ₄In parallel by clamp diode.Above-mentioned auxiliary IGBT moduleT ₁Trigger and brachium pontis first in A, C phase " logical sum " of individual submodule trigger is consistent；Auxiliary IGBT moduleT ₂Trigger and brachium pontis under B phaseNIndividual submodule The trigger of block is consistent.

During the conversion of orthogonal stream energy, each submodule replaces input, bypass, assists IGBT moduleT ₁、T ₂Hand over For closure, turn off, between A, B phase upper and lower bridge arm, capacitance voltage, in the presence of clamp diode, meets lower column constraint：

Auxiliary capacitorC ₁、C ₂Between voltage, auxiliary capacitorC ₃、C ₄There is inequality constraints condition between voltage：

It follows that in half-bridge/mono- clamp series-parallel connection MMC in the dynamic process completing the conversion of orthogonal stream energy, under satisfaction The constraints in face：

Between C, B phase upper and lower bridge arm, the constraints of the capacitance voltage constraints alternate with A, B is consistent.

Illustrated from above-mentioned, this half-bridge/mono- clamp series-parallel connection MMC topology possesses submodule capacitor voltage and certainly equalizes energy Power.

Finally it should be noted that：Described embodiment is only some embodiments of the present application, rather than whole realities Apply example.Based on the embodiment in the application, those of ordinary skill in the art are obtained under the premise of not making creative work Every other embodiment, broadly fall into the application protection scope.

Claims (4)

1. the centralized half-bridge of the auxiliary capacitor based on inequality constraints/mono- clamp series-parallel connection MMC from all press topology it is characterised in that： Including the half-bridge being made up of A, B, C three-phase/mono- clamp series-parallel connection MMC model, each brachium pontis of A, B, C three-phase respectively byKIndividual half-bridge Module,N-KIndividual single clamp submodule and 1 brachium pontis reactor are in series；Including by 6KIndividual mechanical switch, 6N-6KIndividual The auxiliary switch of IGBT module composition, 6N+ 7 clamp diodes, 4 auxiliary capacitorsC ₁、C ₂ 、C ₃、C ₄, 2 auxiliary IGBT ModuleT ₁、T ₂Constitute all presses subsidiary loop certainly.

2. the centralized half-bridge/mono- clamp series-parallel connection MMC of the auxiliary capacitor based on inequality constraints according to claim 1 is from all Pressure topology it is characterised in that：A phase upper and lower bridge arm, in single clamp submodule, diode connexon module capacitance positive pole, IGBT mould Block connexon module capacitance negative pole；1st submodule of brachium pontis, its submodule electric capacity in A phaseC _{au­_1}Negative pole downwards with A phase on 2nd sub- module I GBT module midpoint of brachium pontis is connected, its submodule IGBT module midpoint upwards with dc bus positive pole phase Connect；The of brachium pontis in A phaseiIndividual submodule, whereiniValue be 2～K- 1, its submodule electric capacityC _{au­_i} Negative pole is downward With brachium pontis in A phasei+ 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint upwards with A phase on The of brachium pontisi- 1 sub- module capacitanceC _{au­_i-1}Negative pole is connected；The of brachium pontis in A phaseKIndividual half-bridge submodule, its submodule Block electric capacityC _{au­_K} Negative pole downwards with brachium pontis in A phase theK+ 1 sub- module I GBT module midpoint is connected, its submodule IGBT Module midpoint upwards with brachium pontis in A phaseK- 1 sub- module capacitanceC _{au­_K-1}Negative pole is connected；The of brachium pontis in A phasej Individual submodule, whereinjValue beK+ 2～N- 1, its submodule diode and IGBT module tie-point bridge downwards and in A phase Armj+ 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint upwards with brachium pontis in A phasej- 1 submodule diode is connected with IGBT module tie-point；Brachium pontis in A phaseNIndividual submodule, its submodule diode with IGBT module tie-point is down through two brachium pontis reactorsL ₀Module I GBT module midpoint sub- with the 1st of brachium pontis under A phase is connected Connect, its submodule IGBT module midpoint upwards with brachium pontis in A phaseN- 1 submodule diode and IGBT module tie-point It is connected；The of brachium pontis under A phaseiIndividual submodule, whereiniValue be 2～K- 1, its submodule electric capacityC _{al­_i} Negative pole to Lower the with brachium pontis under A phasei+ 1 sub- module I GBT module midpoint is connected, its IGBT module midpoint upwards with brachium pontis under A phasei- 1 sub- module capacitanceC _{al­_i-1}Negative pole is connected；The of brachium pontis under A phaseKIndividual submodule, its submodule electric capacityC _{al_K} Negative Extremely downwards with brachium pontis under A phase theK+ 1 sub- module I GBT module midpoint is connected, and its submodule IGBT module midpoint is upwards With brachium pontis under A phaseK- 1 sub- module capacitanceC _{al­_K-1}Negative pole is connected；Brachium pontis under A phasejIndividual submodule, whereinj's Value isK+ 2～N- 1, its submodule diode and IGBT module tie-point brachium pontis the downwards and under A phasej+ 1 submodule IGBT module midpoint is connected, its submodule IGBT module midpoint upwards with brachium pontis under A phasej- 1 submodule diode with IGBT module tie-point is connected；Brachium pontis under A phaseNIndividual submodule diode and IGBT module tie-point are downwards and direct current is female Line negative pole is connected, its submodule IGBT module midpoint upwards with brachium pontis under A phaseN- 1 submodule diode and IGBT Module tie-point is connected；B phase upper and lower bridge arm, in single clamp submodule, IGBT module connexon module capacitance positive pole, diode Connexon module capacitance negative pole, the 1st submodule of upper brachium pontis, its submodule electric capacityC _{bu­_1}Positive pole is upwards with dc bus just Pole is connected, its submodule IGBT module midpoint the 2nd sub- module capacitance with brachium pontis in B phase downwardsC _{bu­_2}Positive pole is connected； The of brachium pontis in B phaseiIndividual submodule, whereiniValue be 2～K- 1, its submodule electric capacityC _{bu­_i} Positive pole upwards with B phase The of upper brachium pontisi- 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint downwards with brachium pontis in B phase ?i+ 1 sub- module capacitanceC _{bu­_i+1}Positive pole is connected；The of brachium pontis in B phaseKIndividual submodule, its submodule electric capacityC _{bu­_K} Positive pole upwards with brachium pontis in B phaseK- 1 sub- module I GBT module midpoint is connected, in its submodule IGBT module Point downwards with brachium pontis in B phase theK+ 1 sub- module I GBT module is connected with diode connection point；The of brachium pontis in B phasejIndividual Submodule, whereinjValue beK+ 2～N- 1, its submodule IGBT module and diode connection point upwards with brachium pontis in B phase Thej- 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint downwards with brachium pontis in B phase thej+ 1 Submodule IGBT module is connected with diode connection point；Brachium pontis in B phaseNIndividual submodule, its submodule IGBT module and two Pole pipe tie-point upwards with brachium pontis in B phaseN- 1 sub- module I GBT module midpoint is connected, in its submodule IGBT module O'clock down through two brachium pontis reactorsL ₀The 1st sub- module capacitance with brachium pontis under B phaseC _{bl­_1}Positive pole is connected；Brachium pontis under B phase ?iIndividual submodule, whereiniValue be 2～K- 1, its submodule electric capacityC _{bl_i} Positive pole upwards with brachium pontis under B phasei- 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint downwards with brachium pontis under B phase thei+ 1 Submodule electric capacityC _{bl­_i+1}Positive pole is connected；The of brachium pontis under B phaseKIndividual submodule, its submodule electric capacityC _{bl_K} Positive pole is upwards With brachium pontis under B phaseK- 1 sub- module I GBT module midpoint is connected, its submodule IGBT module midpoint downwards with bridge under B phase ArmK+ 1 sub- module I GBT module is connected with diode connection point；Brachium pontis under B phasejIndividual submodule, whereinjTake It is worth and beK+ 2～N- 1, its submodule IGBT module and diode connection point upwards with brachium pontis under B phasej- 1 submodule IGBT module midpoint is connected, its submodule IGBT module midpoint downwards with brachium pontis under B phase thej+ 1 sub- module I GBT module It is connected with diode connection point；Brachium pontis under B phaseNIndividual submodule, its submodule IGBT module is with diode connection point upwards With brachium pontis under B phaseN- 1 sub- module I GBT module midpoint is connected, and its submodule IGBT module midpoint is downwards and direct current is female Line negative pole is connected；The connected mode of C phase upper and lower bridge arm submodule can consistent with A it is also possible to consistent with B；Due to list The presence of clamp submodule, unnecessary configuration IGCT between the upper and lower output line of half-bridge submodule；Therefore A, B, C phase upper and lower bridge arm is sub It is parallel with mechanical switch between the output line up and down of moduleK _{au_i1}、K _{al_i1}、K _{bu_i1}、K _{bl_i1}、K _{cu_i1}、K _{cl_i1}、K _{au_j} 、K _{al_j} 、K _{bu_j} 、K _{bl_j} 、K _{cu_j} 、K _{cl_j} , whereiniValue be 1～K,jValue beK+ 1～N；On A, B, C three-phase status stating annexation composition is consistent.

3. the centralized half-bridge/mono- clamp series-parallel connection MMC of the auxiliary capacitor based on inequality constraints according to claim 1 is from all Pressure topology it is characterised in that：From all pressing in subsidiary loop, auxiliary capacitorC ₁With auxiliary capacitorC ₂It is in parallel by clamp diode, Auxiliary capacitorC ₂Positive pole connects auxiliary IGBT moduleT ₁, auxiliary capacitorC ₁Negative pole connects clamp diode and is just being incorporated to dc bus Pole；Auxiliary capacitorC ₃With auxiliary capacitorC ₄In parallel, the auxiliary capacitor by clamp diodeC ₃Negative pole connects auxiliary IGBT moduleT ₂, auxiliary capacitorC ₄Positive pole connects clamp diode and is incorporated to dc bus negative pole；Clamp diode, by auxiliary switchK _{au_12} Connect the 1st sub- module capacitance in brachium pontis in A phaseC _{au­_1}With auxiliary capacitorC ₁Positive pole；By auxiliary switchK _{au_i2}、K _{au_（i+1）2}Connect in A phase in brachium pontis theiIndividual sub- module capacitanceC _{au­_i} Withi+ 1 sub- module capacitanceC _{au­_i+1}Just Pole, whereiniValue be 1～K-1；By auxiliary switchK _{au_K2}、T _{au_K+1}Connect in A phase in brachium pontis theKIndividual submodule Electric capacityC _{au­_K} WithK+ 1 sub- module capacitanceC _{au_K+1}Positive pole；By auxiliary switchT _{au_j} 、T _{au_j+1}Connect brachium pontis in A phase InjIndividual sub- module capacitanceC _{au­_j} Withj+ 1 sub- module capacitanceC _{­au­_j+1}Positive pole, whereinjValue beK+ 1～N-1；By auxiliary switchT _{au_N} 、K _{al_12}Connect in A phase in brachium pontis theNIndividual sub- module capacitanceC _{au_N} With brachium pontis the 1st under A phase Individual sub- module capacitanceC _{­al­_1}Positive pole；By auxiliary switchK _{al_i2}、K _{al_（i+1）2}Connect under A phase in brachium pontis theiIndividual submodule electricity HoldC _{­al­_i} Withi+ 1 sub- module capacitanceC _{­al­_i+1}Positive pole, whereiniValue be 1～K-1；By auxiliary switchK _{al_K2}、T _{al_K+1}Connect under A phase in brachium pontis theKIndividual sub- module capacitanceC­_{al­_K} WithK+ 1 sub- module capacitanceC­_{al­_K+1}Just Pole；By auxiliary switchT _{al_j} 、T _{al_j+1}Connect under A phase in brachium pontis thejIndividual sub- module capacitanceC _{­al_j} Withj+ 1 submodule Electric capacityC _{­al­_j+1}Positive pole, whereinjValue beK+ 1～N-1；By auxiliary switchT _{al_N} Connect under A phase in brachium pontis theN Individual sub- module capacitanceC _{­al_N} With auxiliary capacitorC ₃Positive pole；Clamp diode, by auxiliary switchK _{bu_12}Connect in brachium pontis in B phase 1st sub- module capacitanceC _{­bu­_1}With auxiliary capacitorC ₂Negative pole；By auxiliary switchK _{bu_i2}、K _{bu_（i+1）2}Connect brachium pontis in B phase IniIndividual sub- module capacitanceC­_{bu­_i} Withi+ 1 sub- module capacitanceC­_{bu­_i+1}Negative pole, whereiniValue be 1～K-1； By auxiliary switchK _{bu_K2}、T _{bu_K+1}Connect in B phase in brachium pontis theKIndividual sub- module capacitanceC­_{bu­_K} WithK+ 1 submodule Electric capacityC­_{bu­_K+1}Negative pole；By auxiliary switchT _{bu_j} 、T _{bu_j+1}Connect in B phase in brachium pontis thejIndividual sub- module capacitanceC­_{bu­_j} With Thej+ 1 sub- module capacitanceC­_{bu­_j+1}Negative pole, whereinjValue beK+ 1～N-1；By auxiliary switchT _{bu_N} 、K _{bl_12} Connect in B phase in brachium pontis theNIndividual sub- module capacitanceC­_{bu­_N} With the 1st sub- module capacitance in brachium pontis under B phaseC­_{bl_1}Negative pole；Logical Cross auxiliary switchK _{bl_i2}、K _{bl_（i+1）2}Connect under B phase in brachium pontis theiIndividual sub- module capacitanceC­_{bl­_i} Withi+ 1 submodule Electric capacityC­_{bl­_i+1}Negative pole, whereiniValue be 1～K-1；By auxiliary switchK _{bl_K2}、T _{bl_K+1}Connect in brachium pontis under B phase TheKIndividual sub- module capacitanceC­_{bl_K} WithK+ 1 sub- module capacitanceC­_{bl­_K+1}Negative pole；By auxiliary switchT _{bl_j} 、T _{bl_j+1}Even Connect in brachium pontis under B phasejIndividual sub- module capacitanceC­_{bl­_j} Withj+ 1 sub- module capacitanceC­_{bl_j+1}Negative pole, whereinjValue ForK+ 1～N-1；By auxiliary switchT _{bl_N} Connect under B phase in brachium pontis theNIndividual sub- module capacitanceC _{bl­_N} With auxiliary capacitorC ₄Negative pole；The annexation of C phase clamp diode is corresponding with the annexation of its submodule；6 in above-mentioned A, B, C three-phaseNIndividual Auxiliary switchK _{au_i2}、K _{al_i2}、K _{bu_i2}、K _{bl_i2}、K _{cu_i2}、K _{cl_i2}、T _{au_j} 、T _{al_j} 、T _{bu_j} 、T _{bl_j} 、T _{cu_j} 、T _{cl_j} , WhereiniValue be 1～K,jValue beK+ 1～N, 6N+ 7 clamp diodes, 4 auxiliary capacitorsC ₁、C ₂、C ₃、C ₄And 2 auxiliary IGBT moduleT ₁、T ₂, collectively form from all pressure subsidiary loops.

4. the centralized half-bridge/mono- clamp series-parallel connection MMC of the auxiliary capacitor based on inequality constraints according to claim 1 is from all Pressure topology it is characterised in that：During normal condition, from all pressure subsidiary loops 6NIndividual auxiliary switchK _{au_i2}、K _{al_i2}、K _{bu_i2}、K _{bl_i2}、K _{cu_i2}、K _{cl_i2}、T _{au_j} 、T _{al_j} 、T _{bu_j} 、T _{bl_j} 、T _{cu_j} 、T _{cl_j} Normally closed, whereiniValue be 1～K,j Value beK+ 1～N；During failure condition, 6N-6KIndividual auxiliary switchT _{au_j} 、T _{al_j} 、T _{bu_j} 、T _{bl_j} 、T _{cu_j} 、T _{cl_j} Disconnect, whereinjValue beK+ 1～N；Under normal circumstances, first sub- module capacitance of brachium pontis in A phaseC _{au­_1}During bypass, Now assist IGBT moduleT ₁Disconnect, submodule electric capacityC _{au­_1}With auxiliary capacitorC ₁In parallel by clamp diode；Bridge in A phase ArmiIndividual sub- module capacitanceC _{au­_i} During bypass, whereiniValue be 2～N, submodule electric capacityC _{au­_i} With submodule electric capacityC _{au­_i-1}In parallel by clamp diode；First sub- module capacitance of brachium pontis under A phaseC _{al_1}During bypass, submodule electric capacityC _{al­_1} By clamp diode, two brachium pontis reactorsL ₀With submodule electric capacityC _{au­_N} In parallel；Brachium pontis under A phaseiIndividual submodule electricity HoldC _{al_i} During bypass, whereiniValue be 2～N, submodule electric capacityC _{al­_i} With submodule electric capacityC _{al_i-1}By clamper two Pole pipe is in parallel；Auxiliary IGBT moduleT ₂During closure, auxiliary capacitorC ₃By clamp diode and submodule electric capacityC _{al_N} In parallel； Auxiliary IGBT moduleT ₁During closure, auxiliary capacitorC ₂With submodule electric capacityC _{bu­_1}In parallel by clamp diode；Brachium pontis in B phase TheiIndividual sub- module capacitanceC _{bu­_i} During bypass, whereiniValue be 1～N- 1, submodule electric capacityC _{bu­_i} With submodule electric capacityC _{bu­_i+1}In parallel by clamp diode；Brachium pontis in B phaseNIndividual sub- module capacitanceC _{bu_N} During bypass, submodule electric capacityC _{bu­_N} By clamp diode, two brachium pontis reactorsL ₀With submodule electric capacityC _{bl­_1}In parallel；Brachium pontis under B phaseiIndividual submodule electricity HoldC _{bl_i} During bypass, whereiniValue be 1～N- 1, submodule electric capacityC _{bl­_i} With submodule electric capacityC _{bl_i+1}By clamper Diodes in parallel；Brachium pontis under B phaseNIndividual sub- module capacitanceC _{bl_N} During bypass, submodule electric capacityC _{bl­_N} With auxiliary capacitorC ₄ In parallel by clamp diode；Wherein assist IGBT moduleT ₁Trigger and the triggering of first submodule of brachium pontis in A, C phase " logical sum " of signal is consistent；Auxiliary IGBT moduleT ₂Trigger and brachium pontis under B phaseNThe trigger of individual submodule Unanimously；During the conversion of orthogonal stream energy, each submodule replaces input, bypass, assists IGBT moduleT ₁、T ₂Alternately Closure, shutoff, A phase upper and lower bridge arm submodule capacitor voltage, in the presence of clamp diode, meets lower column constraint,U _C1≥U _{C­au_1}≥U _{C­au_2}…≥U _{C­au_N} ≥U _{C­al_1}≥U _{C­al_2}…≥U _{C­al_N} ≥U _C3；B phase upper and lower bridge arm submodule electric capacity Voltage, in the presence of clamp diode, meets lower column constraint,U _C2≤U _{C­bu_1}≤U _{C­bu_2}…≤U _{C­bu_N} ≤U _{C­bl_1}≤U _{C­bl_2}…≤U _{C­bl_N} ≤U _C4；Against auxiliary capacitorC ₁、C ₂Between voltage, auxiliary capacitorC ₃、C ₄Between voltage two Individual inequality constraints,U _C1≤U _C2,U _C3≥U _C4, 4 in A, B phase upper and lower bridge armNIndividual sub- module capacitance,C _{au_i} 、C_{al_i} 、C _{bu_i} 、C _{bl_i} , whereiniValue be 1～N, and auxiliary capacitorC ₁、C ₂、C ₃、C ₄, voltage be in self-balancing state, Topological A, B are alternate to possess submodule capacitor voltage from the ability of equalization；If in topology, the form of the composition of C phase is consistent with A, C, B The constraints of capacitive coupling voltage is consistent with capacitance voltage constraints between A, B；If the form of the composition of C phase and B in topology Consistent, then the constraints of A, C capacitive coupling voltage is consistent with capacitance voltage constraints between A, B.