CN107370410B - Cascaded H-bridges inverter control method and control device - Google Patents
Cascaded H-bridges inverter control method and control device Download PDFInfo
- Publication number
- CN107370410B CN107370410B CN201710625980.8A CN201710625980A CN107370410B CN 107370410 B CN107370410 B CN 107370410B CN 201710625980 A CN201710625980 A CN 201710625980A CN 107370410 B CN107370410 B CN 107370410B
- Authority
- CN
- China
- Prior art keywords
- bridge module
- bridge
- ovennodulation
- triple
- frequency harmonics
- 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.)
- Active
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
- H02M7/53—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 using devices of a triode or transistor type requiring continuous application of a control signal
- H02M7/537—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 using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
- H02M7/5387—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 using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
-
- 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
Abstract
This application discloses cascaded H-bridges inverter control method and control devices, this method comprises: identifying the H bridge module of ovennodulation in Cascade H bridge inverter and the H bridge module of non-ovennodulation；The triple-frequency harmonics of the H bridge module compensation positive of respectively each ovennodulation, compensation rate, which is subject to, guarantees that the modulation wave amplitude of this H bridge module is equal to 1；The triple-frequency harmonics of the H bridge module compensation reverse phase of respectively each not ovennodulation, compensation rate is no more than 1 with the modulation wave amplitude for guaranteeing this H bridge module, and total compensation rate of the H bridge module of all not ovennodulations is equal to subject to total compensation rate of the H bridge module of all ovennodulations, to inhibit each H bridge module ovennodulation in Cascade H bridge inverter.
Description
Technical field
The present invention relates to technical field of photovoltaic power generation, more specifically to cascaded H-bridges inverter control method and control
Device.
Background technique
The topological structure of Cascade H bridge inverter is as shown in Figure 1, include multiple H bridge modules, the input of each H bridge module terminates
Independent photovoltaic module, output end series connection.The Cascade H bridge inverter is approximately using sinusoidal pulse width modulation strategy output waveform
The alternating current of sine wave, and it is sent into power grid.
In practical application, when having shadow occlusion or other reasons that certain output power of photovoltaic module is caused to decline, it is defeated
The output voltage of the corresponding H bridge module of the normal photovoltaic module of power will increase out, and modulation degree can also increase, or even occur
Ovennodulation, it is unstable so as to cause power network current degradation even system.
How effectively to solve the problems, such as H bridge module ovennodulation, is the key that improve cascaded H-bridges gird-connected inverter performance.
Summary of the invention
In view of this, the present invention provides cascaded H-bridges inverter control method and control device, to inhibit cascaded H-bridges inverse
Become each H bridge module ovennodulation in device.
A kind of cascaded H-bridges inverter control method, comprising:
Identify the H bridge module of ovennodulation in Cascade H bridge inverter and the H bridge module of non-ovennodulation；
The triple-frequency harmonics of the H bridge module compensation positive of respectively each ovennodulation, compensation rate is to guarantee the tune of this H bridge module
Wave amplitude processed is equal to subject to 1；
The triple-frequency harmonics of the H bridge module compensation reverse phase of respectively each not ovennodulation, compensation rate is to guarantee this H bridge module
It modulates wave amplitude and is no more than 1, and total compensation rate of the H bridge module of all not ovennodulations is equal to the H bridge module of all ovennodulations
Total compensation rate subject to.
Wherein, the 1st in the Cascade H bridge inverter, 2 ..., x H bridge module is the H bridge module of ovennodulation, xth+
1 ..., n H bridge module is the H bridge module of not ovennodulation；
Described is respectively the triple-frequency harmonics of the H bridge module compensation positive of each ovennodulation, and compensation rate is to guarantee this H bridge module
Modulation wave amplitude be equal to 1 subject to, comprising:
Obtain the modulation degree S of i-th of H bridge modulei, i=1,2 ..., x；
According to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki, three times as i-th of H bridge module
Harmonic compensation coefficient；Wherein, the curve C2Be in Cascade H bridge inverter any one H bridge module modulation wave amplitude be 1
When, curve that modulation degree changes with triple-frequency harmonics penalty coefficient；
According to SiAnd ki, obtain the modulating wave m of i-th of H bridge moduleiFor
mi=Si×sin(θ+θr)+kiSi×sin(3θ+θr)
In formula, θ is electric network voltage phase angle, θrFor the difference of total modulation voltage and electric network voltage phase angle.
Wherein, described according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki, comprising: using tabling look-up
Method, according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki。
Alternatively, described according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki, comprising: utilize curve
Fitting process, according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki。
Wherein, described is respectively that the H bridge module of each not ovennodulation compensates the triple-frequency harmonics of reverse phase, and compensation rate is to guarantee this
The modulation wave amplitude of H bridge module is no more than 1, and total compensation rate of the H bridge module of all not ovennodulations is equal to all ovennodulations
H bridge module total compensation rate subject to, comprising:
Calculate the amplitude V for total third harmonic voltage that the H bridge modules of all ovennodulations is compensatedT3Are as follows:
In formula, VdciFor the DC voltage of i-th of H bridge module；
Calculate the maximum voltage amplitude V that j-th of H bridge module allows to compensatedcj(max) are as follows:
Vdcj(max)=Vdcj-SjVdcj
In formula, VdcjFor the DC voltage of j-th of H bridge module, j=x+1 ..., n；
Calculate the third harmonic voltage amplitude V that j-th of H bridge module is compensatedcjWith penalty coefficient kjFor
Vcj=VT3/Vdcj
According to VcjAnd kjThe modulating wave m of j-th of H bridge module is calculatedjFor
mj=Sj×sin(θ+θr)+kjVcj×sin(3θ+θr)。
A kind of cascaded H-bridges control device for inverter, comprising:
Recognition unit, for identification out in Cascade H bridge inverter the H bridge module of ovennodulation and non-ovennodulation H bridge module；
First compensating unit, for be respectively each ovennodulation H bridge module compensation positive triple-frequency harmonics, compensation rate with
Guarantee that the modulation wave amplitude of this H bridge module is equal to subject to 1；
Second compensating unit, for being respectively that the H bridge module of each not ovennodulation compensates the triple-frequency harmonics of reverse phase, compensation rate
To guarantee that the modulation wave amplitude of this H bridge module is no more than 1, and total compensation rate of the H bridge module of all not ovennodulations is equal to institute
Subject to the total compensation rate for having the H bridge module of ovennodulation.
Wherein, the 1st in the Cascade H bridge inverter, 2 ..., x H bridge module is the H bridge module of ovennodulation, xth+
1 ..., n H bridge module is the H bridge module of not ovennodulation；
First compensating unit is specifically used for obtaining the modulation degree S of i-th of H bridge modulei, i=1,2 ..., x；According to song
Line C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki, triple-frequency harmonics penalty coefficient as i-th of H bridge module；Its
In, the curve C2It is that for any one H bridge module when modulating wave amplitude is 1, modulation degree is with humorous three times in Cascade H bridge inverter
The curve of wave penalty coefficient variation；According to SiAnd ki, obtain the modulating wave m of i-th of H bridge moduleiFor
mi=Si×sin(θ+θr)+kiSi×sin(3θ+θr)
In formula, θ is electric network voltage phase angle, θrFor the difference of total modulation voltage and electric network voltage phase angle.
Wherein, first compensating unit uses look-up table, according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics is mended
Repay coefficient ki。
Alternatively, first compensating unit uses curve-fitting method, according to curve C2It obtains and SiIt is unique corresponding humorous three times
Wave penalty coefficient ki。
Wherein, the H bridge module that second compensating unit is specifically used for calculating all ovennodulations compensated it is total three times
The amplitude V of harmonic voltageT3Are as follows:
In formula, VdciFor the DC voltage of i-th of H bridge module；
Calculate the maximum voltage amplitude V that j-th of H bridge module allows to compensatedcj(max) are as follows:
Vdcj(max)=Vdcj-SjVdcj
In formula, VdcjFor the DC voltage of j-th of H bridge module, j=x+1 ..., n；
Calculate the third harmonic voltage amplitude V that j-th of H bridge module is compensatedcjWith penalty coefficient kjFor
Vcj=VT3/Vdcj
According to VcjAnd kjThe modulating wave m of j-th of H bridge module is calculatedjFor
mj=Sj×sin(θ+θr)+kjVcj×sin(3θ+θr)。
It can be seen from the above technical scheme that the present invention compensates the humorous three times of positive by the H bridge module to ovennodulation
Wave makes it modulate wave amplitude 1, while in order to make all total output voltages of H bridge module without containing third-harmonic component, needing to mend
It repays the triple-frequency harmonics of equivalent reverse phase and is reasonably allocated to the H bridge module of not ovennodulation, finally guarantee all H bridge module not tonings
System.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
Some embodiments of invention for those of ordinary skill in the art without creative efforts, can be with
It obtains other drawings based on these drawings.
Fig. 1 is a kind of cascaded H-bridges inverter topology schematic diagram disclosed in the prior art；
Fig. 2 is a kind of cascaded H-bridges inverter control method flow chart disclosed by the embodiments of the present invention；
Fig. 3 is the modulating wave waved surface figure of H bridge module；
Fig. 4 is the X-Z view of Fig. 3；
Fig. 5 is the forward and backward waveform diagram of the triple-frequency harmonics of the H bridge module compensation positive of certain ovennodulation；
Fig. 6 is that the H bridge module of certain not ovennodulation compensates the forward and backward waveform diagram of triple-frequency harmonics of reverse phase；
Fig. 7 is the method flow diagram that the triple-frequency harmonics of positive is compensated to the H bridge module of ovennodulation；
Fig. 8 is max (v of the H bridge module in S=1r)-k curve graph, and in max (vrS-k curve graph when)=1；
Fig. 9 is the method flow diagram that the triple-frequency harmonics of reverse phase is compensated to the H bridge module of not ovennodulation；
Figure 10 is a kind of cascaded H-bridges control device for inverter structural schematic diagram disclosed by the embodiments of the present invention.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
Referring to fig. 2, the embodiment of the invention discloses a kind of cascaded H-bridges inverter control methods, comprising:
Step S01: the H bridge module of ovennodulation in Cascade H bridge inverter and the H bridge module of non-ovennodulation are identified.
Specifically, the H bridge module of so-called ovennodulation, refers to that modulation wave amplitude is greater than the H bridge module of carrier amplitude.It is so-called not
The H bridge module of ovennodulation refers to that modulation wave amplitude is not more than the H bridge module of carrier amplitude.By comparing the modulating wave of H bridge module
The size of amplitude and carrier amplitude, that is, may recognize that the H bridge module whether ovennodulation.
Step S02: being respectively the triple-frequency harmonics of the H bridge module compensation positive of each ovennodulation, compensation rate is to guarantee this H bridge
The modulation wave amplitude of module is equal to subject to 1；
Step S03: being respectively the triple-frequency harmonics of the H bridge module compensation reverse phase of each not ovennodulation, compensation rate is to guarantee this H
The modulation wave amplitude of bridge module is no more than 1, and total compensation rate of the H bridge module of all not ovennodulations is equal to all ovennodulations
Subject to total compensation rate of H bridge module.
The present embodiment is to inhibit each H bridge module ovennodulation in Cascade H bridge inverter using injection triple-frequency harmonics method.For
The technical solution of clearer description the present embodiment, is below described in detail its working principle.
The output voltage of Cascade H bridge inverter is free of third-harmonic component, any one H bridge mould in Cascade H bridge inverter
The output voltage of block is also free of third-harmonic component.Triple-frequency harmonics is being compensated to any one H bridge module in Cascade H bridge inverter
Afterwards, the modulating wave v of this H bridge modulerFor
vr=S × sin (wt)+kS × sin (3wt) (1)
In formula, S is the modulation degree of this H bridge module, and k is that the triple-frequency harmonics penalty coefficient of this H bridge module (compensates when k > 0
It is the triple-frequency harmonics of positive, what when k < 0 compensated is the triple-frequency harmonics of reverse phase；| k | bigger, compensation rate is bigger), w is angular frequency
Rate, t are the time.
For formula (1), S=1 is kept, draws out v with MATLABrThe surface chart such as Fig. 3 institute changed with variable wt and k
Show.The X-Z view of Fig. 3 is as shown in figure 4, the longitudinal axis of Fig. 4 is the equal of the modulation wave amplitude max (v of this H bridge moduler)。
As shown in Figure 4,0≤k≤1/6 is monotone decreasing region, that is to say, that: it is compensated to the H bridge module of ovennodulation certain
The triple-frequency harmonics for measuring positive, can reduce the modulation wave amplitude max (v of this H bridge moduler), to inhibit this H to a certain extent
Bridge module ovennodulation；Moreover, when k=1/6, max (vr) reach minimum, this H bridge module ovennodulation can be inhibited to greatest extent.
Moreover, also known by Fig. 4, when k < 0, the modulation wave amplitude max (v of this H bridge moduler) > 1, and k < 0 is single
Adjust incremental zone, that is to say, that: the triple-frequency harmonics of a certain amount of reverse phase is compensated to H bridge module, will increase the H bridge module of not ovennodulation
The risk of ovennodulation；Moreover, the compensation rate of reverse phase triple-frequency harmonics is bigger, got over not the risk of the H bridge module ovennodulation of ovennodulation
It is high.
By analyzing above it is found that when H bridge module ovennodulations certain in Cascade H bridge inverter, by the H bridge for giving ovennodulation
The triple-frequency harmonics of a certain amount of positive of module for compensating can inhibit these H bridge module ovennodulations to a certain extent.But due to cascade
Third-harmonic component should not be contained in the output voltage of H bridge inverter, so a certain amount of in the H bridge module compensation to ovennodulation
While the triple-frequency harmonics of positive, it is also necessary to compensate the triple-frequency harmonics of a certain amount of reverse phase, and institute to the H bridge module of not ovennodulation
There is total compensation rate of the reverse phase triple-frequency harmonics of the H bridge module of not ovennodulation that should be equal to the positive of H bridge module of all ovennodulations
Total compensation rate of triple-frequency harmonics so just can guarantee that the positive and negative phase triple-frequency harmonics compensated into Cascade H bridge inverter mutually supports
Disappear, so that the output voltage of the total output voltage of all H bridge modules namely Cascade H bridge inverter is free of third-harmonic component.
And should be noted that in the triple-frequency harmonics of the H bridge module compensation positive to ovennodulation, it cannot pursue simply
Inhibit this H bridge module ovennodulation (i.e. setting k=1/6) to greatest extent, but should be according to output power between each H bridge module
Uneven degree, reasonable compensation compensate to the modulation wave amplitude of the H bridge module of ovennodulation and are down to 1, to reduce not toning
There is the risk of ovennodulation because compensating the triple-frequency harmonics of equivalent reverse phase in the H bridge module of system.
For example, by taking two H bridge modules as an example, it is assumed that the modulation wavelength-division of first H bridge module and second H bridge module
Not as shown in formula (2) and formula (3).
vr1=1.1sin (wt) (2)
vr2=0.85sin (wt) (3)
It is obvious that first H bridge module ovennodulation, second H bridge module not ovennodulation.To solve first H bridge module
The problem of ovennodulation, compensates the maximum amount of positive triple-frequency harmonics to first H bridge module, while in order to guarantee that two H bridge modules are total
Output voltage be free of triple-frequency harmonics, to the triple-frequency harmonics of second H bridge module compensation equivalent reverse phase, after the compensation of two H bridge modules
Modulating wave respectively as shown in formula (4) and formula (5).
y1=1.1sin (wt)+1.1/6*sin (3wt) (4)
y2=0.85sin (wt) -1.1/6*sin (3wt) (5)
According to formula (2) and formula (4) draw out first H bridge module compensate forward and backward modulating wave waveform diagram as shown in figure 5,
Drawing out second H bridge module according to formula (3) and formula (5), to compensate forward and backward modulating wave waveform diagram as shown in Figure 6.By Fig. 5 and figure
6 it is found that the compensated modulation wave amplitude of first H bridge module less than 1, solves the problems, such as first H bridge module ovennodulation, but
The compensated modulation wave amplitude of second H bridge module is greater than 1, produces new ovennodulation problem, this compensates humorous three times with us
The original intention of wave is disagreed.
Fig. 5 is observed it is found that having certain allowance between compensated modulation wave amplitude and 1 of first H bridge module, if
The triple-frequency harmonics penalty coefficient k for suitably reducing first H bridge module is compensated first H bridge module to modulation wave amplitude
It is 1, then not only can guarantee first H bridge module not ovennodulation, but also the risk of second H bridge module ovennodulation can be made to reduce.
So for the Cascade H bridge inverter containing n H bridge module, it is assumed that some time has inscribed x H bridge module toning
System, for ease of description, the number for defining the H bridge module of this x ovennodulation is followed successively by 1,2 ..., x, while it is a to define remaining n-x
Not the number of the H bridge module of ovennodulation be followed successively by x+1 ..., n.To i-th (i=1,2 ..., x) a H bridge module compensation positive
When triple-frequency harmonics, compensation rate, which is subject to, guarantees that the modulation wave amplitude of i-th of H bridge module is equal to 1 (the i.e. described step S02)；Meanwhile
The triple-frequency harmonics of the H bridge module compensation reverse phase of respectively each not ovennodulation, compensation rate is to guarantee the modulation wave amplitude of this H bridge module
Value is no more than 1, and the compensation rate summation of the H bridge module of all not ovennodulations is equal to the compensation of the H bridge module of all ovennodulations
It measures subject to summation (the i.e. described step S03).
The specific implementation of the step S02 as shown in fig. 7, comprises:
Step S021: obtain i-th (i=1,2 ..., x) a H bridge module modulation degree Si；
Step S022: according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki, as i-th of H bridge mould
The triple-frequency harmonics penalty coefficient of block；Wherein, the curve C2Be in Cascade H bridge inverter any one H bridge module in modulating wave
Amplitude max (vr) when being 1, curve that modulation degree S changes with triple-frequency harmonics penalty coefficient k.
Specifically, S=1 is kept, according to formula (1) for any one H bridge module in Cascade H bridge inverter
Draw out the modulation wave amplitude max (v of the H bridge moduler) with the curve of k variation, such as curve C in Fig. 81It is shown；According to curve C1It can
To draw out modulation wave amplitude max (vr) be 1 when, the curve that S changes with k, such as curve C in Fig. 82It is shown.As seen from Figure 8,
In the region of 0≤k≤1/6, S and k are corresponded, and the value range of S is 1~1.155.
For i-th of H bridge module, according to curve C2It can find and modulation degree SiUnique corresponding triple-frequency harmonics compensation system
Number ki, can specifically use look-up table or curve-fitting method is found and SiUnique corresponding ki。
The look-up table refers to according to curve C2, in the section 0≤k≤1/6, several suitable points are chosen, in practical system
When system operation, by calculating the modulation wave amplitude of i-th of H bridge module, selection and its closest approach, it can calculate corresponding
kiValue.
The curve-fitting method refers to according to curve C2Draw out max (vr) be 1 when, k passes through choosing with the change curve of S
A series of suitable points are taken, the mathematic(al) representation of S and k are fitted.When real system is run, by the modulating wave of i-th of H bridge module
Amplitude substitutes into the mathematic(al) representation, can calculate corresponding kiValue.
Step S023: according to SiAnd ki, obtain the modulating wave m of i-th of H bridge moduleiFor
mi=Si×sin(θ+θr)+kiSi×sin(3θ+θr)
In formula, θ is electric network voltage phase angle, θrFor the difference of total modulation voltage and electric network voltage phase angle.
Total compensation rate of reverse phase triple-frequency harmonics is reasonably allocated to the H bridge module of each not ovennodulation by the step S03, is protected
The H bridge module of card compensation reverse phase triple-frequency harmonics will not ovennodulation, distribution method is as shown in Figure 9, comprising:
Step S301: the amplitude V for total third harmonic voltage that the H bridge modules of all ovennodulations is compensated is calculatedT3Are as follows:
In formula, VdciFor the DC voltage of i-th of H bridge module.
Step S302: calculating a H bridge module of jth (j=x+1 ..., n) allows the maximum voltage amplitude V of compensationdcj
(max) are as follows:
Vdcj(max)=Vdcj-SjVdcj (7)
In formula, VdcjFor the DC voltage of j-th of H bridge module.
Step S303: the third harmonic voltage amplitude V that j-th of H bridge module is compensated is calculatedcjWith penalty coefficient kjFor
Vcj=VT3/Vdcj (8)
Step S304: the modulating wave m of j-th of H bridge module is calculated according to formula (8) and formula (9)jFor
mi=Sj×sin(θ+θr)+kjVcj×sin(3θ+θr) (10)
Seen from the above description, the present embodiment compensates the triple-frequency harmonics of positive by the H bridge module to ovennodulation, makes its tune
Wave amplitude processed is 1, while in order to make all total output voltages of H bridge module without containing third-harmonic component, needing to compensate equivalent anti-
The triple-frequency harmonics of phase and the H bridge module for being reasonably allocated to not ovennodulation finally guarantee all H bridge modules not ovennodulations.
In addition, the embodiment of the invention discloses a kind of cascaded H-bridges control device for inverter referring to Figure 10, comprising:
Recognition unit 100, for identification out in Cascade H bridge inverter the H bridge module of ovennodulation and non-ovennodulation H bridge mould
Block；
First compensating unit 200, for being respectively that the H bridge module of each ovennodulation compensates the triple-frequency harmonics of positive, compensation
Amount, which is subject to, guarantees that the modulation wave amplitude of this H bridge module is equal to 1；
Second compensating unit 300 is mended for being respectively that the H bridge module of each not ovennodulation compensates the triple-frequency harmonics of reverse phase
The amount of repaying is to guarantee that the modulation wave amplitude of this H bridge module is no more than 1, and total compensation rate of H bridge module etc. of all not ovennodulations
Subject to total compensation rate of the H bridge module of all ovennodulations.
Wherein, the 1st in the Cascade H bridge inverter, 2 ..., x H bridge module is the H bridge module of ovennodulation, xth+
1 ..., n H bridge module is the H bridge module of not ovennodulation；
First compensating unit 200 is specifically used for obtaining the modulation degree S of i-th of H bridge modulei, i=1,2 ..., x；According to song
Line C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki, triple-frequency harmonics penalty coefficient as i-th of H bridge module；Its
In, the curve C2It is that for any one H bridge module when modulating wave amplitude is 1, modulation degree is with humorous three times in Cascade H bridge inverter
The curve of wave penalty coefficient variation；According to SiAnd ki, obtain the modulating wave m of i-th of H bridge moduleiFor
mi=Si×sin(θ+θr)+kiSi×sin(3θ+θr)
In formula, θ is electric network voltage phase angle, θrFor the difference of total modulation voltage and electric network voltage phase angle.
Wherein, the first compensating unit 200 uses look-up table, according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics is mended
Repay coefficient ki。
Alternatively, the first compensating unit 200 uses curve-fitting method, according to curve C2It obtains and SiIt is unique corresponding humorous three times
Wave penalty coefficient ki。
Wherein, the H bridge module that the second compensating unit 300 is specifically used for calculating all ovennodulations is compensated total humorous three times
The amplitude V of wave voltageT3Are as follows:
In formula, VdciFor the DC voltage of i-th of H bridge module；
Calculate the maximum voltage amplitude V that j-th of H bridge module allows to compensatedcj(max) are as follows:
Vdcj(max)=Vdcj-SjVdcj
In formula, VdcjFor the DC voltage of j-th of H bridge module, j=x+1 ..., n；
Calculate the third harmonic voltage amplitude V that j-th of H bridge module is compensatedcjWith penalty coefficient kjFor
Vcj=VT3/Vdcj
According to VcjAnd kjThe modulating wave m of j-th of H bridge module is calculatedjFor
mj=Sj×sin(θ+θr)+kjVcj×sin(3θ+θr)。
In conclusion the present invention compensates the triple-frequency harmonics of positive by the H bridge module to ovennodulation, it is made to modulate wave amplitude
It is 1, while in order to make all total output voltages of H bridge module without containing third-harmonic component, needs to compensate equivalent reverse phase three times
Harmonic wave and the H bridge module for being reasonably allocated to not ovennodulation finally guarantee all H bridge modules not ovennodulations.
Each embodiment in this specification is described in a progressive manner, the highlights of each of the examples are with other
The difference of embodiment, the same or similar parts in each embodiment may refer to each other.For device disclosed in embodiment
For, since it is corresponded to the methods disclosed in the examples, so being described relatively simple, related place is said referring to method part
It is bright.
Herein, relational terms such as first and second and the like be used merely to by an entity or operation with it is another
One entity or operation distinguish, and without necessarily requiring or implying between these entities or operation, there are any this reality
Relationship or sequence.
The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention.
Various modifications to these embodiments will be readily apparent to those skilled in the art, as defined herein
General Principle can be realized in other embodiments in the case where not departing from the spirit or scope of the embodiment of the present invention.Therefore,
The embodiment of the present invention is not intended to be limited to the embodiments shown herein, and be to fit to principles disclosed herein and
The consistent widest scope of features of novelty.
Claims (10)
1. a kind of cascaded H-bridges inverter control method characterized by comprising
Identify the H bridge module of ovennodulation in Cascade H bridge inverter and the H bridge module of non-ovennodulation；
The triple-frequency harmonics of the H bridge module compensation positive of respectively each ovennodulation, compensation rate is to guarantee the modulating wave of this H bridge module
Amplitude is equal to subject to 1；
The triple-frequency harmonics of the H bridge module compensation reverse phase of respectively each not ovennodulation, compensation rate is to guarantee the modulation of this H bridge module
Wave amplitude is no more than 1, and total compensation rate of the H bridge module of all not ovennodulations is equal to the total of the H bridge module of all ovennodulations
Subject to compensation rate.
2. cascaded H-bridges inverter control method according to claim 1, which is characterized in that in the Cascade H bridge inverter
1st, 2 ..., x H bridge module be ovennodulation H bridge module, (x+1)th ..., n H bridge module be not ovennodulation H bridge module；
Described is respectively the triple-frequency harmonics of the H bridge module compensation positive of each ovennodulation, and compensation rate is to guarantee the tune of this H bridge module
Wave amplitude processed is equal to subject to 1, comprising:
Obtain the modulation degree S of i-th of H bridge modulei, i=1,2 ..., x；
According to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki, triple-frequency harmonics as i-th of H bridge module
Penalty coefficient；Wherein, the curve C2It is that any one H bridge module is adjusted when modulating wave amplitude is 1 in Cascade H bridge inverter
The curve that system changes with triple-frequency harmonics penalty coefficient；
According to SiAnd ki, obtain the modulating wave m of i-th of H bridge moduleiFor
mi=Si×sin(θ+θr)+kiSi×sin(3θ+θr)
In formula, θ is electric network voltage phase angle, θrFor the difference of total modulation voltage and electric network voltage phase angle.
3. cascaded H-bridges inverter control method according to claim 2, which is characterized in that described according to curve C2Obtain with
SiUnique corresponding triple-frequency harmonics penalty coefficient ki, comprising:
Using look-up table, according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki。
4. cascaded H-bridges inverter control method according to claim 2, which is characterized in that described according to curve C2Obtain with
SiUnique corresponding triple-frequency harmonics penalty coefficient ki, comprising:
Using curve-fitting method, according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki。
5. cascaded H-bridges inverter control method according to claim 2, which is characterized in that it is described be respectively it is each only
Modulation H bridge module compensation reverse phase triple-frequency harmonics, compensation rate with guarantee this H bridge module modulation wave amplitude be no more than 1, and
Total compensation rate of the H bridge module of all not ovennodulations is equal to subject to total compensation rate of the H bridge module of all ovennodulations, comprising:
Calculate the amplitude V for total third harmonic voltage that the H bridge modules of all ovennodulations is compensatedT3Are as follows:
In formula, VdciFor the DC voltage of i-th of H bridge module；
Calculate the maximum voltage amplitude V that j-th of H bridge module allows to compensatedcj(max) are as follows:
Vdcj(max)=Vdcj-SjVdcj
In formula, VdcjFor the DC voltage of j-th of H bridge module, SjIndicate the modulation degree of j-th of H bridge module, j=x+1 ..., n；
Calculate the third harmonic voltage amplitude V that j-th of H bridge module is compensatedcjWith penalty coefficient kjFor
Vcj=VT3/Vdcj
According to VcjAnd kjThe modulating wave m of j-th of H bridge module is calculatedjFor
mj=Sj×sin(θ+θr)+kjVcj×sin(3θ+θr)。
6. a kind of cascaded H-bridges control device for inverter characterized by comprising
Recognition unit, for identification out in Cascade H bridge inverter the H bridge module of ovennodulation and non-ovennodulation H bridge module；
First compensating unit, for being respectively that the H bridge module of each ovennodulation compensates the triple-frequency harmonics of positive, compensation rate is to guarantee
The modulation wave amplitude of this H bridge module is equal to subject to 1；
Second compensating unit, for being respectively that the H bridge module of each not ovennodulation compensates the triple-frequency harmonics of reverse phase, compensation rate is to protect
The modulation wave amplitude for demonstrate,proving this H bridge module is no more than 1, and total compensation rate of the H bridge module of all not ovennodulations is equal to all mistakes
Subject to total compensation rate of the H bridge module of modulation.
7. cascaded H-bridges control device for inverter according to claim 6, which is characterized in that in the Cascade H bridge inverter
1st, 2 ..., x H bridge module be ovennodulation H bridge module, (x+1)th ..., n H bridge module be not ovennodulation H bridge module；
First compensating unit is specifically used for obtaining the modulation degree S of i-th of H bridge modulei, i=1,2 ..., x；According to curve C2
It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki, triple-frequency harmonics penalty coefficient as i-th of H bridge module；Wherein,
The curve C2It is that for any one H bridge module when modulating wave amplitude is 1, modulation degree is with triple-frequency harmonics in Cascade H bridge inverter
The curve of penalty coefficient variation；According to SiAnd ki, obtain the modulating wave m of i-th of H bridge moduleiFor
mi=Si×sin(θ+θr)+kiSi×sin(3θ+θr)
In formula, θ is electric network voltage phase angle, θrFor the difference of total modulation voltage and electric network voltage phase angle.
8. cascaded H-bridges control device for inverter according to claim 7, which is characterized in that first compensating unit is adopted
With look-up table, according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki。
9. cascaded H-bridges control device for inverter according to claim 7, which is characterized in that first compensating unit is adopted
With curve-fitting method, according to curve C2It obtains and SiUnique corresponding triple-frequency harmonics penalty coefficient ki。
10. cascaded H-bridges control device for inverter according to claim 7, which is characterized in that the second compensating unit tool
The amplitude V for total third harmonic voltage that the H bridge module that body is used to calculate all ovennodulations is compensatedT3Are as follows:
In formula, VdciFor the DC voltage of i-th of H bridge module；
Calculate the maximum voltage amplitude V that j-th of H bridge module allows to compensatedcj(max) are as follows:
Vdcj(max)=Vdcj-SjVdcj
In formula, VdcjFor the DC voltage of j-th of H bridge module, SjIndicate the modulation degree of j-th of H bridge module, j=x+1 ..., n；
Calculate the third harmonic voltage amplitude V that j-th of H bridge module is compensatedcjWith penalty coefficient kjFor
Vcj=VT3/Vdcj
According to VcjAnd kjThe modulating wave m of j-th of H bridge module is calculatedjFor
mj=Sj×sin(θ+θr)+kjVcj×sin(3θ+θr)。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710625980.8A CN107370410B (en) | 2017-07-27 | 2017-07-27 | Cascaded H-bridges inverter control method and control device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710625980.8A CN107370410B (en) | 2017-07-27 | 2017-07-27 | Cascaded H-bridges inverter control method and control device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107370410A CN107370410A (en) | 2017-11-21 |
| CN107370410B true CN107370410B (en) | 2019-09-20 |
Family
ID=60307873
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710625980.8A Active CN107370410B (en) | 2017-07-27 | 2017-07-27 | Cascaded H-bridges inverter control method and control device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107370410B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108429476B (en) * | 2018-03-28 | 2020-03-24 | 阳光电源股份有限公司 | Control method and controller of cascaded H-bridge inverter |
| CN108599609B (en) * | 2018-05-14 | 2019-11-26 | 合肥博鳌电气科技有限公司 | A kind of improvement phase-shifting carrier wave modulator approach based on three module-cascade H bridges |
| CN109066699B (en) * | 2018-09-04 | 2021-11-02 | 兰州理工大学 | Method for judging influence of overmodulation on micro-source inverter series micro-grid voltage |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0833355A (en) * | 1994-07-18 | 1996-02-02 | Nippon Electric Ind Co Ltd | Inverter system of carrier frequency modulation by high-frequency transformer coupling |
| CN101615860A (en) * | 2009-07-23 | 2009-12-30 | 东南大学 | Be applied to a kind of modulator approach of cascade converter |
| CN103580519A (en) * | 2013-10-28 | 2014-02-12 | 华中科技大学 | Dual-mode SVPWM overmodulation method |
| CN105790302A (en) * | 2016-04-11 | 2016-07-20 | 阳光电源股份有限公司 | Cascade type photovoltaic grid-connected inverter and control method thereof and control device thereof |
| CN106340886A (en) * | 2016-08-30 | 2017-01-18 | 山东大学 | Novel control method suitable for cascaded H bridge static var compensator |
-
2017
- 2017-07-27 CN CN201710625980.8A patent/CN107370410B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0833355A (en) * | 1994-07-18 | 1996-02-02 | Nippon Electric Ind Co Ltd | Inverter system of carrier frequency modulation by high-frequency transformer coupling |
| CN101615860A (en) * | 2009-07-23 | 2009-12-30 | 东南大学 | Be applied to a kind of modulator approach of cascade converter |
| CN103580519A (en) * | 2013-10-28 | 2014-02-12 | 华中科技大学 | Dual-mode SVPWM overmodulation method |
| CN105790302A (en) * | 2016-04-11 | 2016-07-20 | 阳光电源股份有限公司 | Cascade type photovoltaic grid-connected inverter and control method thereof and control device thereof |
| CN106340886A (en) * | 2016-08-30 | 2017-01-18 | 山东大学 | Novel control method suitable for cascaded H bridge static var compensator |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107370410A (en) | 2017-11-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107370410B (en) | Cascaded H-bridges inverter control method and control device | |
| Li et al. | Suppressing EMI in power converters via chaotic SPWM control based on spectrum analysis approach | |
| DE102015210734B4 (en) | MANAGEMENT OF CRYPTOGRAPHIC KEYS | |
| US10985554B2 (en) | Equilibrium-conductance-compensated eccentric method for obtaining power transfer coefficients of direct current power networks | |
| Garrett et al. | Special values of triple product L-functions | |
| DE102011003866A1 (en) | Methods, systems and apparatus for approximating peak sum and third harmonic voltages in a polyphase machine | |
| US20150357933A1 (en) | Method for designing cascaded multi-level inverter with minimized large-scale voltage distortion | |
| CN108429476B (en) | Control method and controller of cascaded H-bridge inverter | |
| CN109004649A (en) | A kind of LCL filter resonance inhibition device and method based on active damping | |
| CN104866866A (en) | Improved natural gradient variable step-size blind source separation algorithm | |
| CN103545841B (en) | The control method of a kind of inverter, device and inverter system | |
| CN103746582B (en) | Parallel connection type multi-electrical level inverter control method and parallel connection type multi-electrical level inverter | |
| Merdan et al. | Solution of nonlinear oscillators with fractional nonlinearities by using the modified differential transformation method | |
| CN110429896A (en) | A kind of voltage modulated method and device | |
| CN112600405B (en) | Control method and device of unidirectional PFC circuit and terminal equipment | |
| CN105826950A (en) | Inverter virtual impedance vector diagram analysis method | |
| CN109921672A (en) | Three-phase inverter minimum switch losses method based on dual carrier and synthesis modulating wave | |
| CN105207511A (en) | Control method of convertor, apparatus and system | |
| CN110061646A (en) | A kind of method, equipment and the storage medium of three-level inverter neutral balance | |
| CN108667326A (en) | A kind of multi-level converter selective harmonic elimination pulsewidth modulation Fast implementation | |
| CN104092395A (en) | Modularized multi-level converter valve set control method | |
| Wong | Harmonic analysis of PWM multi-level converters | |
| CN109066699B (en) | Method for judging influence of overmodulation on micro-source inverter series micro-grid voltage | |
| CN104104253B (en) | Inverter power control method and device | |
| CN104038092A (en) | Control method for power balance of hybrid multilevel inverter |
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 |