CN109639171A - A kind of five phase three-level current transformer neutral point voltage balance methods based on hybrid modulation - Google Patents
A kind of five phase three-level current transformer neutral point voltage balance methods based on hybrid modulation Download PDFInfo
- Publication number
- CN109639171A CN109639171A CN201910043067.6A CN201910043067A CN109639171A CN 109639171 A CN109639171 A CN 109639171A CN 201910043067 A CN201910043067 A CN 201910043067A CN 109639171 A CN109639171 A CN 109639171A
- Authority
- CN
- China
- Prior art keywords
- phase
- modulation
- level
- duty ratio
- cbpwm
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- 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
- H02M7/487—Neutral point clamped inverters
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
The present invention relates to a kind of methods that hybrid modulation realizes five phases, three level neutral-point-clamped type current transformer neutral point voltage balance, the hybrid modulation is based on CBPWM modulation and VSVPWM modulation, the method includes, the voltage and current of five phase three-level current transformers output is acquired first, and rearrange the size of output voltage, then possible CBPWM modulation strategy is proposed, determine each phase sequence of levels, on this basis, in conjunction with voltage-second balance principle, the sum of duty ratio of three level of the condition of neutral point voltage balance and each phase is equal to 1, acquire the duty ratio model and all equilibrium regions under CBPWM modulation strategy, simultaneously, in order to realize the neutral point voltage balance in the uneven region under CBPWM modulation strategy, introduce VSVPWM modulation strategy, and acquire duty ratio model, finally, according to duty ratio Model calculates double modulation wave, by it compared with carrier wave, to generate specific PWM sequence.
Description
Technical field
The present invention relates to the sides that the balance of voltage in five phase three-level current transformers is realized based on CBPWM and VSVPWM hybrid modulation
Method, neutral point voltage balance are that the condition of five phase three-level current transformer energy stable operations can only be one using CBPWM modulation strategy
Neutral point voltage balance is realized in fixed range, to realize the neutral point voltage balance in gamut, also requires to introduce VSVPWM tune
System strategy.
Background technique
With the development of power electronics technology, three-level current transformer, which receives, widely pays close attention to, especially in large capacity, high electricity
It has a meeting, an audience, etc. well under one's control conjunction.Compared to two traditional level current transformers, three-level current transformer has lower total harmonic distortion factor, lower device
Voltage stress and higher energy conversion efficiency.
Traditional three-phase motor drive system is constantly subjected to the limitation of the power supply number of phases and is unable to effective development.Recently as
The high speed development of computer technology, power electronic technique and modern control theory, the bottleneck that gradually overcoming.Five-phase induction motor
System reliability with higher, using the theory of phase redundancy when design, occur opening a way when a stator winding or
When the bridge arm open circuit of inverter, the normal operation of motor will not be significantly affected；The torque pulsation amplitude of five-phase induction motor system
It is smaller than three-phase motor, but ripple frequency increases；The low voltage power devices that low cost can be used in five-phase induction motor drive system are come real
Existing high-power driving control；Therefore, five-phase induction motor system is suitably applied the higher occasion of high-power or reliability requirement
Neutral point voltage balance is the prerequisite that can guarantee current transformer safe and reliable operation, and common has mid-point voltage
The modulator approach of balanced capacity has: based on carried based PWM (CBPWM) method, the space vector tune adjusted based on redundant vectors
(SVPWM) method of system and Virtual Space Vector Pulse Width Modulation (VSVPWM) method.Wherein, although CBPWM method has low open
The characteristic of loss is closed, but can not achieve the neutral point voltage balance within the scope of complete modulation degree and total power factor；SVPWM method is logical
The action time of each vector of Vector modulation regulation arrangement is spent, but calculation amount is huge, is not easy to realize；VSVPWM method is being adjusted entirely
Within the scope of system and total power factor, have neutral point voltage balance ability, but increases the common-mode voltage of system.These modulation methods
Method is studied based on three-phase tri-level current transformer mostly, and the research expanded to five phase three-level current transformers is then fewer.
Therefore, it in order to realize the safe and reliable operations of five phase three-level current transformers, provides a kind of in complete modulation degree and complete
Within the scope of power factor, the method for realizing neutral point voltage balance.
Summary of the invention
The object of the invention is that solve the above-mentioned problems, proposing to realize based on CBPWM and VSVPWM hybrid modulation
The method of neutral point voltage balance in five phase three-level current transformer gamuts, to enable the system to safe and stable operation.
The present invention through the following technical solutions to achieve the above objectives:
The five phase three-level current transformer neutral point voltage balance methods based on hybrid modulation that the present invention provides a kind of, including such as
Lower step:
Step S1, the voltage and current of five phase three-level current transformers of acquisition output, and the voltage is carried out according to size
Sequence；
Step S2, based on the voltage and CBPWM modulation strategy after sequence, the electricity under different CBPWM modulating modes is determined
Flat sequence；
Step S3, according to voltage-second balance principle, duty cycle constraints condition and neutral point voltage balance condition, CBPWM is acquired
Duty ratio model and all equilibrium regions under modulation strategy；
Step S4, VSVPWM modulation strategy is introduced into uneven region, and acquires duty ratio model, to realize in gamut
Neutral point voltage balance.
Step S5, according to the duty ratio model in step S4, double modulation wave is calculated, it is compared with carrier wave, with
Generate the PWM sequence of particular sequence.
Further, in the step S1, the voltage and current of output is respectively indicated are as follows:
Wherein, ω t ∈ [0,2 π] is the phase angle of 1 phase voltage, and m ∈ [0,1.05] is modulation degree, udcIt is direct current side bus electricity
The half of pressure, ImIt is the peak value of phase current,It is the power-factor angle of load；According to the instantaneous value of five phase output voltages, from greatly to
Small successively renamed as uI、uII、uIII、uIVAnd uV.The phase voltage u rearrangedI、uII、uIII、uIVAnd uVCorresponding phase current note
For iI、iII、iIII iIVAnd iV。
Further, in the step S2, the CBPWM modulation strategy includes six kinds, determines different CBPWM modulating modes
Under sequence of levels specifically, in a control period, if modulating wave uj> 0, then its output sequence is by 2 level and 1 level group
At being denoted as (2,1)；If modulating wave uj< 0, then its output sequence is made of 1 level and 0 level, is denoted as (1,0), it can thus be concluded that six
Sequence of levels under kind modulation strategy specifically:
Further, in the step S3, voltage-second balance principle, the line voltage and every phase of five phase three-level current transformers are based on
The relationship of the sum of duty ratio is expressed as:
Gd=H (1)
Wherein,
D=[dI2,dI1,dI0,dII2,dII1,dII0,dIII2,dIII1,dIII0,dIV2,dIV1,dIV0,dV2,dV1,dV0]T, djnTable
Show the duty ratio of the n-th level of jth phase, wherein j=I, II, III, IV and V, n=0,1 and 2, H=[uI-uII,uII-uIII,uIII-
uIV,uIV-uV]T,
The duty cycle constraints condition is that the sum of each three level duty ratios of phase are equal to 1:
The neutral point voltage balance condition are as follows:
iNP=iIdI1+iIIdII1+iIIIdIII1+iIVdIV1+iVdV1=0 (3)
By above-mentioned (1), (2), (3) He Gexiang sequence of levels, the duty ratio model under various CBPWM modulation strategies is found out,
When duty ratio model meets 0≤djn≤ 1, it is exactly the equilibrium region under various CBPWM modulation strategies, it is exactly entire for seeking it union
Equilibrium region under CBPWM modulation strategy.
Further, the step S4, the duty ratio model of VSVPWM modulation strategy are as follows:
dI1=dII1=dIII1=dIV1=dV1 (4)
Above formula indicates that each 1 level duty ratio of phase of three-level current transformer is equal, wherein djnIndicate the duty of the n-th level of jth phase
Than j=I, II, III, IV and V, n=0,1 and 2, in VSVPWM modulation strategy, maximum voltage is mutually without 0 level, minimum electricity
Pressure obtains mutually without 2 level:
dI0=dV2=0 (5)
By above-mentioned (1), (2), (4) and (5), to find out the duty ratio model under VSVPWM modulation strategy,
Further, the step S5 is specifically included,
Under CBPWM modulation strategy, the expression formula of modulating wave is obtained according to duty ratio model:
uj=(dj,2-dj,0)udc
Under VSVPWM modulation strategy, the expression formula of double modulation wave is obtained according to duty ratio model:
In formula, dj,nIndicate the duty ratio of the n-th level of jth phase, wherein j=I, II, III, IV and V, n=0,1 and 2, according to
The three-phase modulations wave of the calculating, the double modulation wave and same carrier wave of every phase are compared, and obtain two groups of PWM sequences of every phase,
Two groups of PWM sequences of every phase are added again, obtain complete PWM sequence.
The beneficial effects of the present invention are:
1) it by the neutral point voltage balance modulator approach of three-phase tri-level current transformer, is extended in five phase three-level current transformers
2) in order to realize neutral point voltage balance of the five phase three-level current transformers within the scope of complete modulation degree and total power factor,
Propose a kind of hybrid modulation method based on CBPWM and VSVPWM
Detailed description of the invention
Fig. 1 is the flow chart of hybrid modulation method proposed by the present invention；
Fig. 2 is the main circuit diagram of five phase three-level current transformer of neutral-point-clamped type of the present invention
Fig. 3 CBPWM modulation strategy modulated wave is compared with carrier wave to generate PWM sequence
Fig. 4 VSVPWM modulation strategy modulated wave is compared with carrier wave to generate PWM sequence
Fig. 5 am ∈ [0,1.0515],When CBPWM modulation strategy under equilibrium region
Fig. 5 b m ∈ [0,1.0515],When CBPWM modulation strategy under equilibrium region
Fig. 5 c m ∈ [0,1.0515],When CBPWM modulation strategy under equilibrium region
Fig. 6 in different m andThe shared percentage of lower VSVPWM modulation
Fig. 7 in different m andThe lower region modulated using CBPWM
Specific embodiment
The application is described in further detail with reference to the accompanying drawing, it is necessary to it is indicated herein to be, implement in detail below
Mode is served only for that the application is further detailed, and should not be understood as the limitation to the application protection scope, the field
Technical staff can make some nonessential modifications and adaptations to the application according to above-mentioned application content.
Embodiment 1
It present embodiments provides a kind of based on five phase three-level current transformer midpoints of CBPWM and VSVPWM hybrid modulation realization electricity
The method for flattening weighing apparatus as shown in Figure 1, acquiring the voltage and current of five phase three-level current transformers output first, and rearranges defeated
Then voltage out proposes possible CBPWM modulation, determines each phase sequence of levels, flat according to voltage-second balance principle, mid-point voltage
The conditions such as weighing apparatus obtain duty ratio model and all equilibrium regions under CBPWM modulation strategy, meanwhile, uneven region introduces
VSVPWM modulation strategy, acquires duty ratio model, realizes the neutral point voltage balance in gamut, finally according to duty ratio model,
Double modulation wave is calculated, by it compared with carrier wave, to generate specific PWM sequence.
Step S1, the voltage and current of five phase three-level current transformers of acquisition output, and the voltage is carried out according to size
Sequence；
Wherein, ω t ∈ [0,2 π] is the phase angle of 1 phase voltage, and m ∈ [0,1.05] is modulation degree, udcIt is direct current side bus electricity
The half of pressure, ImIt is the peak value of phase current,It is the power-factor angle of load；According to the instantaneous value of five phase output voltages, from greatly to
Small successively renamed as uI、uII、uIII、uIVAnd uV.The phase voltage u rearrangedI、uII、uIII、uIVAnd uVCorresponding phase current note
For iI、iII、iIII iIVAnd iV。
Step S2, based on the voltage and CBPWM modulation strategy after sequence, the electricity under different CBPWM modulating modes is determined
Flat sequence；
As shown in Fig. 2, when upper and lower capacitor voltage balance, there is u using capacitor midpoint as reference pointC1=uC2=udc, direct current
Side bus voltage is 2udc.2 level are defined as the conducting of S1 and S2 pipe, output voltage uC1；1 level is defined as S2 and S3 pipe and leads
It is logical, output voltage 0；0 level is defined as the conducting of S3 and S4 pipe, and output voltage is-uC2；In a control period, if modulation
Wave uj> 0, then its output sequence is made of 2 level and 1 level, is denoted as (2,1)；If modulating wave uj< 0, then its output sequence is by 1 electricity
Gentle 0 level composition, is denoted as (1,0):
Step S3, according to voltage-second balance principle, duty cycle constraints condition and neutral point voltage balance condition, CBPWM is acquired
Duty ratio model and all equilibrium regions under modulation strategy；
Based on voltage-second balance principle, the relationship of the sum of the line voltage of five phase three-level current transformers and every phase duty ratio can be with table
It is shown as:
Gd=H (1)
Wherein,
D=[dI2,dI1,dI0,dII2,dII1,dII0,dIII2,dIII1,dIII0,dIV2,dIV1,dIV0,dV2,dV1,dV0]T, djnTable
Show the duty ratio of the n-th level of jth phase, wherein j=I, II, III, IV and V, n=0,1 and 2, H=[uI-uII,uII-uIII,uIII-
uIV,uIV-uV]T,
The duty cycle constraints condition is that the sum of each three level duty ratios of phase are equal to 1:
The neutral point voltage balance condition are as follows:
iNP=iIdI1+iIIdII1+iIIIdIII1+iIVdIV1+iVdV1=0 (3)
By above-mentioned (1), (2), (3) He Gexiang sequence of levels, the duty ratio model under various CBPWM modulation strategies is found out,
When duty ratio model meets 0≤djn≤ 1, it is exactly the equilibrium region under various CBPWM modulation strategies, it is exactly entire for seeking it union
Equilibrium region under CBPWM modulation strategy.
Step S4, VSVPWM modulation strategy is introduced into uneven region, and acquires duty ratio model, to realize in gamut
Neutral point voltage balance；
In the step S4, the duty ratio model of VSVPWM modulation strategy are as follows:
dI1=dII1=dIII1=dIV1=dV1 (4)
Above formula indicates that each 1 level duty ratio of phase of three-level current transformer is equal, wherein djnIndicate the duty of the n-th level of jth phase
Than j=I, II, III, IV and V, n=0,1 and 2, in VSVPWM modulation strategy, maximum voltage is mutually without 0 level, minimum electricity
Pressure obtains mutually without 2 level:
dI0=dV2=0 (5)
By above-mentioned (1), (2), (4) and (5), to find out the duty ratio model under VSVPWM modulation strategy,
Step S5, according to duty ratio model, modulating wave is calculated, by it compared with carrier wave, to generate specific PWM sequence
Column.
Under CBPWM modulation strategy, the expression formula of modulating wave is obtained according to duty ratio model:
uj=(dj,2-dj,0)udc
As shown in figure 3, giving CBPWM modulation strategy modulated wave compared with carrier wave to generate PWM sequence.Work as modulating wave
uj> 0, export 2 level and 1 level；As modulating wave uj< 0, export 1 level and 0 level；
Under VSVPWM modulation strategy, the expression formula of double modulation wave is obtained according to duty ratio model:
As shown in figure 4, in formula, uj、u′jWith u "jAll indicate that the double modulation wave of the three-level current transformer j phase, above formula provide
VSVPWM modulation strategy modulated wave is compared with carrier wave to generate PWM sequence.According to the modulating wave of the calculating, pair of every phase
The comparison of modulating wave and same carrier wave obtains two groups of PWM sequences of every phase, then two groups of PWM sequences of every phase is added, and has obtained
Whole PWM sequence.
Embodiment 2
Present embodiments provide the neutral balance region under CBPWM modulation
When being in CBPWM5 and CBPWM6 modulating mode, current transformer can be balanced when every phase voltage is zero,
This state, which only may alternatively appear in, powers on initial time, meaningless for the modulation of current transformer, therefore casts out both modulating modes, remaining
Theoretically there is equilibrium region in four kinds of modulating modes, will analyze respectively these four modulating modes below and to solve its specific
Solution:
1)CBPWM1
The specific solution of each phase duty ratio under CBPWM1 modulating mode:
dI2=uI+ucom1,dI1=1-dI2,dI0=0
dII2=uII+ucom1,dII1=1-dII2,dII0=0
dIII2=uIII+ucom1,dIII1=1-dIII2,dIII0=0
dIV2=uIV+ucom1,dIV1=1-dIV2,dIV0=0
dV2=0, dV1=1-dV0,dV0=-uV-ucom1
Wherein, ucom1=(iIuI+iIIuII+iIIIuIII+iIVuIV-iVuV)/2iV, specific when 15 duty ratio state variables
Solution meets 0≤dkn≤ 1, current transformer can maintain neutral point voltage balance state under CBPWM1 modulating mode.
2)CBPWM2
The specific solution of each phase duty ratio under CBPWM2 modulating mode:
dI2=uI+ucom2,dI1=1-dI2,dI0=0
dII2=uII+ucom2,dII1=1-dII2,dII0=0
dIII2=uIII+ucom2,dIII1=1-dIII2,dIII0=0
dIV2=0, dIV1=1-dIV0,dIV0=-uIV-ucom2
dV2=0, dV1=1-dV0,dV0=-uV-ucom2
Wherein, ucom2=(iIuI+iIIuII+iIIIuIII-iIVuIV-iVuV)/2(iIV+iV), when 15 duty ratio state variables
Specific solution meet 0≤dkn≤ 1, current transformer can maintain neutral point voltage balance state under CBPWM2 modulating mode.
3)CBPWM3
The specific solution of each phase duty ratio under CBPWM3 modulating mode:
dI2=u1+ucom3,dI1=1-dI2,dI0=0
dII2=uII+ucom3,dII1=1-dII2,dII0=0
dIII2=0, dIII1=1-dIII0,dIII0=-uIII-ucom3
dIV2=0, dIV1=1-dIV0,dIV0=-uIV-ucom3
dV2=0, dV1=1-dV0,dV0=-uV-ucom3
Wherein, ucom3=(- iIuI-iIIuII+iIIIuIII+iIVuIV+iVuV)/2(iI+iII), when 15 duty ratio states become
The specific solution of amount meets 0≤dkn≤ 1, current transformer can maintain neutral point voltage balance state under CBPWM3 modulating mode.
4)CBPWM4
The specific solution of each phase duty ratio under CBPWM4 modulating mode:
dI2=uI+ucom4,dI1=1-dI2,dI0=0
dII2=0, dII1=1-dII0,dII0=-uII-ucom4
dIII2=0, dIII1=1-dIII0,dIII0=-uIII-ucom4
dIV2=0, dIV1=1-dIV0,dIV0=-uIV-ucom4
dV2=0, dV1=1-dV0,dV0=-uV-ucom4
Wherein, ucom4=(- iIuI+iIIuII+iIIIuIII+iIVuIV+iVuV)/2iI, as the spy of 15 duty ratio state variables
Fixed solution meets 0≤dkn≤ 1, current transformer can maintain neutral point voltage balance state under CBPWM4 modulating mode.
The value of specific solution is related with the instantaneous value of voltage and current and power factor.Balance under asking entire CBPWM to modulate
The union of specific solution under CBPWM1, CBPWM2, CBPWM3 and CBPWM4 modulating mode is exactly sought in region.CBPWM modulating mode
Under, when m ∈ [0,1.0515], ω t ∈ [0,2 π], φ=0, region such as Fig. 5 institute of neutral point voltage balance when π/3and pi/2
Show.When power factor be 1 when, within a control period, CBPWM be modulated in addition to modulation degree very close to 1.0515 exhausted big portion
Subregion can all realize balance.With being gradually increased for power factor, the region that balance can be achieved in the period is controlled at one
It is gradually reduced；When power factor is reduced to zero, only inverter can be made to realize in one cycle at m ∈ [0,0.73]
Balance.
Embodiment 3
Present embodiments provide the respective neutral balance region of CBPWM and VSVPWM hybrid modulation stratgy
Fig. 6 shows the percentage that VSVPWM is modulated in basic cycle hybrid modulation.When m ∈ [0,0.89], Ke Yitong
Crossing CBPWM modulation makes system balancing.When m ∈ [0.89,0.99], VSVPWM modulation percentage with power factor variation
And change.Total trend is when power factor is lower, and the ratio of VSVPWM modulation is lower (minimum value can reach 0%)；Work as function
The ratio that VSVPWM is modulated when rate factor is higher is very high (up to 100%).When m ∈ [0.99,1.05], it is necessary to pass through VSVPWM
Modulation can just make system balancing.In m andEntire scope in, Fig. 7 show in the basic cycle be used only CBPWM modulation make
The region of system balancing.As can be seen that the region close to m andEntire scope 88%.
It is obvious to a person skilled in the art that the embodiment of the present invention is not limited to the details of above-mentioned exemplary embodiment,
And without departing substantially from the spirit or essential attributes of the embodiment of the present invention, this hair can be realized in other specific forms
Bright embodiment.Therefore, in all respects, the present embodiments are to be considered as illustrative and not restrictive, this
The range of inventive embodiments is indicated by the appended claims rather than the foregoing description, it is intended that being equal for claim will be fallen in
All changes in the meaning and scope of important document are included in the embodiment of the present invention.It should not be by any attached drawing mark in claim
Note is construed as limiting the claims involved.Furthermore, it is to be understood that one word of " comprising " does not exclude other units or steps, odd number is not excluded for
Plural number.Multiple units, module or the device stated in system, device or terminal claim can also be by the same units, mould
Block or device are implemented through software or hardware.The first, the second equal words are used to indicate names, and are not offered as any specific
Sequence.
Finally it should be noted that embodiment of above is only to illustrate the technical solution of the embodiment of the present invention rather than limits,
Although the embodiment of the present invention is described in detail referring to the above better embodiment, those skilled in the art should
Understand, can modify to the technical solution of the embodiment of the present invention or equivalent replacement should not all be detached from the skill of the embodiment of the present invention
The spirit and scope of art scheme.
Claims (6)
1. a kind of five phase three-level current transformer neutral point voltage balance methods based on hybrid modulation, include the following steps:
Step S1, the voltage and current of five phase three-level current transformers of acquisition output, and the voltage is ranked up according to size；
Step S2, based on the voltage and CBPWM modulation strategy after sequence, the level sequence under different CBPWM modulating modes is determined
Column；
Step S3, according to voltage-second balance principle, duty cycle constraints condition and neutral point voltage balance condition, CBPWM modulation is acquired
Duty ratio model and all equilibrium regions under strategy；
Step S4, VSVPWM modulation strategy is introduced into uneven region, and acquires duty ratio model, to realize in gamut
The point balance of voltage.
Step S5, according to the duty ratio model in step S4, double modulation wave is calculated, it is compared with carrier wave, to generate
The PWM sequence of particular sequence.
2. neutral point voltage balance method according to claim 1, which is characterized in that in the step S1, the voltage of output
It is respectively indicated with electric current are as follows:
Wherein, ω t ∈ [0,2 π] is the phase angle of 1 phase voltage, and m ∈ [0,1.05] is modulation degree, udcIt is DC side busbar voltage
Half, ImIt is the peak value of phase current,Be load power-factor angle, according to the instantaneous value of five phase output voltages, from big to small according to
Secondary renamed as uI、uII、uIII、uIVAnd uV, the phase voltage u that rearrangesI、uII、uIII、uIVAnd uVCorresponding phase current is denoted as
iI、iII、iIII iIVAnd iV。
3. neutral point voltage balance method according to claim 2, which is characterized in that in the step S2, the CBPWM tune
System strategy includes six kinds, determines the sequence of levels under different CBPWM modulating modes specifically, in a control period, if tune
Wave u processedj> 0, then its output sequence is made of 2 level and 1 level, is denoted as (2,1)；If modulating wave uj< 0, then its output sequence is by 1
Level and 0 level composition, are denoted as (1,0), it can thus be concluded that the sequence of levels under six kinds of modulation strategies specifically:
4. neutral point voltage balance method according to claim 3, which is characterized in that flat based on weber in the step S3
The relationship of the sum of weighing apparatus principle, the line voltage of five phase three-level current transformers and every phase duty ratio is expressed as:
Gd=H (1)
Wherein,
D=[dI2,dI1,dI0,dII2,dII1,dII0,dIII2,dIII1,dIII0,dIV2,dIV1,dIV0,dV2,dV1,dV0]T, djnIndicate jth
The duty ratio of the n-th level of phase, wherein j=I, II, III, IV and V, n=0,1 and 2,
H=[uI-uII,uII-uIII,uIII-uIV,uIV-uV]T,
The duty cycle constraints condition is that the sum of each three level duty ratios of phase are equal to 1:
The neutral point voltage balance condition are as follows:
iNP=iIdI1+iIIdII1+iIIIdIII1+iIVdIV1+iVdV1=0 (3)
By above-mentioned (1), (2), (3) He Gexiang sequence of levels, the duty ratio model under various CBPWM modulation strategies is found out, when accounting for
Sky meets 0≤d than modeljn≤ 1, it is exactly the equilibrium region under various CBPWM modulation strategies, it is exactly entire for seeking it union
Equilibrium region under CBPWM modulation strategy.
5. neutral point voltage balance method according to claim 4, which is characterized in that in the step S4, VSVPWM modulation
The duty ratio model of strategy are as follows:
dI1=dII1=dIII1=dIV1=dV1 (4)
Above formula indicates that each 1 level duty ratio of phase of three-level current transformer is equal, wherein djnIndicate the duty ratio of the n-th level of jth phase, j
=I, II, III, IV and V, n=0,1 and 2, in VSVPWM modulation strategy, maximum voltage is mutually without 0 level, minimum voltage phase
Without 2 level, obtain:
dI0=dV2=0 (5)
By above-mentioned (1), (2), (4) and (5), to find out the duty ratio model under VSVPWM modulation strategy,
6. neutral point voltage balance method according to claim 5, which is characterized in that the step S5 is specifically included,
Under CBPWM modulation strategy, the expression formula of modulating wave is obtained according to duty ratio model:
uj=(dj,2-dj,0)udc
Under VSVPWM modulation strategy, the expression formula of double modulation wave is obtained according to duty ratio model:
In formula, dj,nIndicate the duty ratio of the n-th level of jth phase, wherein j=I, II, III, IV and V, n=0,1 and 2, according to described
The three-phase modulations wave of calculating, the double modulation wave and same carrier wave of every phase are compared, and obtain two groups of PWM sequences of every phase, then will
Two groups of PWM sequences of every phase are added, and obtain complete PWM sequence.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910043067.6A CN109639171B (en) | 2019-01-17 | 2019-01-17 | A kind of five phase three-level current transformer neutral point voltage balance methods based on hybrid modulation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910043067.6A CN109639171B (en) | 2019-01-17 | 2019-01-17 | A kind of five phase three-level current transformer neutral point voltage balance methods based on hybrid modulation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109639171A true CN109639171A (en) | 2019-04-16 |
| CN109639171B CN109639171B (en) | 2019-11-29 |
Family
ID=66061968
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910043067.6A Active CN109639171B (en) | 2019-01-17 | 2019-01-17 | A kind of five phase three-level current transformer neutral point voltage balance methods based on hybrid modulation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109639171B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103117668A (en) * | 2013-02-26 | 2013-05-22 | 哈尔滨工业大学 | Simplified five-phase and three-level voltage source inverter and vector control method thereof |
| CN106788112A (en) * | 2016-12-27 | 2017-05-31 | 上海科梁信息工程股份有限公司 | Motor drives main circuit structure and its signal modulating method, controller |
-
2019
- 2019-01-17 CN CN201910043067.6A patent/CN109639171B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103117668A (en) * | 2013-02-26 | 2013-05-22 | 哈尔滨工业大学 | Simplified five-phase and three-level voltage source inverter and vector control method thereof |
| CN106788112A (en) * | 2016-12-27 | 2017-05-31 | 上海科梁信息工程股份有限公司 | Motor drives main circuit structure and its signal modulating method, controller |
Non-Patent Citations (2)
| Title |
|---|
| SAIFULLAH PAYAMI, ET AL: "Common-Mode Voltage and Vibration Mitigation of a Five-Phase Three-Level NPC Inverter-Fed Induction Motor Drive System", 《IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS》 * |
| 姜卫东等: "全范围内中点电位平衡的三电平变换器调制策略", 《电力系统自动化》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109639171B (en) | 2019-11-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Corzine et al. | Control of cascaded multilevel inverters | |
| CN101753044B (en) | Three-level midpoint potential balance control method based on zero-sequence voltage injection | |
| CN103618491B (en) | SVPWM strategy based on power supply topology of double three-level inverters | |
| CN103401456B (en) | The two carrier modulating method of voltage-type three level neutral-point-clamped current transformer double modulation ripple | |
| CN109217701B (en) | Three-level rectifier common-mode voltage suppression PWM method, modulator and system | |
| Lin | Analysis and implementation of a three-level PWM rectifier/inverter | |
| Pan et al. | Capacitor voltage balancing and stabilization for 4-level hybrid-clamped converter using selected switching states | |
| CN108054948A (en) | NPC current transformer randomized switching frequency modulator approaches based on ripple current peak value | |
| CN105811796B (en) | A kind of three-level inverter neutral point voltage balance and loss reduce control method | |
| CN107947599A (en) | Electronic power convertor | |
| CN105703649B (en) | The control method that a kind of three-level inverter neutral point voltage balance and common-mode voltage inhibit | |
| Kumar et al. | Harmonic suppression scheme for multipulse converter fed multilevel inverter-based IM drive | |
| CN111953223A (en) | Neutral point voltage balancing method for three-phase four-wire system three-level converter | |
| CN102545681A (en) | Step wave synthesis three-phase inverter capable of eliminating low frequency harmonic waves and control method | |
| CN103401457A (en) | Carrier wave modulation method of voltage type three-level neutral point clamped converter | |
| Riedemann et al. | Modulation strategies for an open-end winding induction machine fed by a two-output indirect matrix converter | |
| WO2019073761A1 (en) | Power conversion device | |
| CN109639171B (en) | A kind of five phase three-level current transformer neutral point voltage balance methods based on hybrid modulation | |
| CN105790622B (en) | Control method of five-level active neutral point clamped H-bridge inverter | |
| Choudhury et al. | Modified DC-link voltage balancing algorithm for a 3-level neutral point clamped (NPC) traction inverter based electric vehicle PMSM drive | |
| Islam et al. | Power converter topologies for grid-integrated medium-voltage applications | |
| Aleenejad et al. | A modified space vector modulation method for fault-tolerant operation of multilevel converters | |
| CN111509830B (en) | Topological structure of miniature photovoltaic/energy storage intelligent power station | |
| KR20210016232A (en) | Three-phase npc multilevel inverter | |
| Yepes et al. | Extension to symmetrical and asymmetrical n-phase AC drives of simple carrier-based PWM for prolonged high DC-link utilization |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20220318 Address after: 230001 floor 6, block B, blue diamond Shangjie, No. 335, Suixi Road, Bozhou road street, Luyang District, Hefei City, Anhui Province Patentee after: Hefei Luyang Technology Innovation Group Co.,Ltd. Address before: No. 193, Tunxi Road, Hefei City, Anhui Province Patentee before: Hefei University of Technology |
|
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20220919 Address after: Huangshan Future Science and Technology City, No. 59, Meilin Avenue, Huangshan High-tech Industrial Development Zone, Huangshan City, Anhui Province, 245000 Patentee after: Huangshan Science and Technology Innovation Center Co.,Ltd. Address before: 230001 floor 6, block B, blue diamond Shangjie, No. 335, Suixi Road, Bozhou road street, Luyang District, Hefei City, Anhui Province Patentee before: Hefei Luyang Technology Innovation Group Co.,Ltd. |
|
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20230627 Address after: No. 88, Meilin Avenue, Huangshan City High tech Industrial Development Zone, Mount Huangshan City, Anhui Province 245000 Patentee after: Zhongke Haiao (Mount Huangshan) Energy Storage Technology Co.,Ltd. Address before: Huangshan Future Science and Technology City, No. 59, Meilin Avenue, Huangshan High-tech Industrial Development Zone, Huangshan City, Anhui Province, 245000 Patentee before: Huangshan Science and Technology Innovation Center Co.,Ltd. |