CN108599605A - Three-level inverter model prediction Poewr control method based on two Vector modulations - Google Patents
Three-level inverter model prediction Poewr control method based on two Vector modulations Download PDFInfo
- Publication number
- CN108599605A CN108599605A CN201810454450.6A CN201810454450A CN108599605A CN 108599605 A CN108599605 A CN 108599605A CN 201810454450 A CN201810454450 A CN 201810454450A CN 108599605 A CN108599605 A CN 108599605A
- Authority
- CN
- China
- Prior art keywords
- vector
- cost function
- sector
- inverter
- voltage
- 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
Abstract
The invention discloses a kind of three-level inverter model prediction Poewr control method based on two Vector modulations, the instantaneous active and reactive power of gird-connected inverter is adjusted based on the model prediction power control of two Vector modulations, and balance mid-point voltage；Model prediction power control based on two Vector modulations is divided into two steps, establish two cost functions, the small sector where desired voltage vector is first acquired, two vectors are then selected by rational cost function and adjusts its duty ratio to control each switching device of three-level inverter.The method of the present invention may be implemented switching frequency and fix, and reduce the operand of algorithm, save computing resource, and the inverter stable state of method control and dynamic property all show well.
Description
Technical field
The present invention relates to three-level inverter control technology field, more particularly to a kind of three level based on two Vector modulations
Inverter model prediction power control method.
Background technology
With the getting worse of environmental pollution and energy crisis, sent out using the distribution of the regenerative resources such as solar energy, wind energy
Power technology is by more and more extensive concern.And inverter is the interface of distributed generation system and power grid, with two traditional electricity
Flat inverter is compared, and three-level inverter harmonic content is low, and switching loss is small, and power quality and efficiency will be much higher.
Model Predictive Control is a kind of novel predictive control strategy, which, which needs to establish one, can predict behavior in future
System model, usually construct a cost function, selection makes this cost function reach the optimized switching state of minimum value, just
Predicted value can be made close to desired value.Predictive control algorithm about three-level inverter have earliest model prediction power control and
Model prediction current control.These predictive control algorithms can be with the mid-point voltage of balancing three-level inverter, but both are passed
The switching frequency of system method is all variation, all only selects an optimal voltage vector defeated as voltage in a switch periods
Go out, the no rule of variation of on off state, such output has higher requirement to sample frequency and switching frequency is not fixed, humorous
Wave frequency spectrum is wide, and difficulty is brought to the design of output filter.It is presently used for the prediction optimized switching sequence Direct Power of inverter
Control and modulation pattern predictive control strategy are suggested, and both methods may be implemented fixed switching frequency, but calculation amount compared with
Greatly, and in a switching frequency on off state used has 3, and inverter switching states switching times is caused to increase.
Invention content
The shortcomings that it is an object of the invention to overcome the prior art and deficiency provide a kind of three electricity based on two Vector modulations
Flat inverter model prediction power control method overcomes existing three-level inverter control strategy switching frequency to change, and calculates
Larger disadvantage is measured, realizes constant switching frequency, reduces switching number, reduces the operand of algorithm, saves computing resource.
The purpose of the present invention is realized by the following technical solution：
A kind of three-level inverter model prediction Poewr control method based on two Vector modulations, including：By all 27
A on off state is divided into 12 small sectors on the basis of traditional 6 big sectors；First cost function selection packet of the first step
Small sector where vector containing desired output voltage, in the small sector then obtained in the first step by second cost function
Optimal two vector switch sequence is selected, the corresponding on off state of two vectors of three-level inverter selection is finally utilized, according to
Corresponding duty ratio controls the device for power switching of inverter.
It is as follows：
It under the influence of negligible resistance, finds out in three phase network at static two phase coordinate systems α β, active power and idle
The differential equation of power：
Wherein, (eα,eβ) and (iα,iβ) network voltage and electric current under static two phase coordinate systems α β are represented, L is exchange filter
The inductance of wave device, ω indicate that electrical angular speed, P represent active power, and Q represents reactive power, when inverter switching states are vi
When, the voltage that inverter is exported at static two phase coordinate systems α β is ui(uαi,uβi), be input to grid side active power with it is idle
The derivative of power is expressed as fpi,fqi, so above formula can also be expressed as：
Assuming that active power and reactive power of the three-level inverter when k-th of sampling period starts are respectively P (k), Q
(k), by two voltage vector voltage vector ui,ujT is acted on respectivelyi,tjAfter time, when+1 sampling period of kth starts,
Inverter output active power be with reactive power predicted value：
If the sampling time is Ts, since each sampling period, only there are two vectors to act on, so Ts=ti+tj；
It takes zero vector, the middle big vector of vector sum to form the center of small sector respectively, utilizes this 12 centrally located vectors
Calculate separately the active-power P (k+1) and reactive power Q (k+1) of+1 start time in sampling period of kth；Define a cost
At this moment function, the sector where finding out the center vector for making cost function minimum in result of calculation first do not consider capacitance midpoint
The balance of voltage, defining cost function J ' is：
J '=[Pref-P(k)-fpcTs]2+[Qref-Q(k)-fqcTs]2 (4)
Wherein, PrefIt is given active power value, QrefIt is given reactive power value, and fpc,fqcIt is output center arrow
The change rate for measuring corresponding active power and reactive power finds out the center for making cost function J ' minimums from above-mentioned result of calculation
Sector where vector, then the sector is sector where required two vectors；
It, first will be to each two vectorial combination in small sector most in seeking small sector before optimal two vector switch sequence
Excellent duty ratio is calculated, and the action time of two of which vector is respectively tiAnd tj, tiIt can be by enabling cost function J to ti
Derivation, and it is enabled to be obtained equal to 0, defining cost function J is：
J=Δs P2+ΔQ2=[Pref-P(k)-fpiti-fpjtj]2+[Qref-Q(k)-fqiti-fqjtj]2 (5)
It obtains calculating tiFormula be：
In addition, by Ts=ti+tjObtain tj=Ts-ti；
In cost function, consider that neutral point voltage balance, mid-point voltage equation are：
Wherein, uo=uc2-uc1For the voltage difference of bus capacitor, C is the size of two capacitances of DC side, viabcFor inverter
On off state, tiIt is the corresponding effect duration of on off state, | viabc|={ | via|,|vib|,|vic|}T,vix(x=a, b, c)
∈ { -1,0,1 }, iabcIt is the line current and i of connected systemabc={ ia,ib,ic}；
Consider capacitance neutral point voltage balance, find out in small sector the optimal two vector switch sequence in a switch periods,
Defining cost function J " is：
J "=[Pref-P(k)-fpiti-fpjtj]2+[Qref-Q(k)-fqiti-fqjtj]2+λ|uo(k+1)| (8)
Being found out from above-mentioned result of calculation makes cost function be minimized corresponding two vectors, is corresponded to according on off sequence
Duty ratio, synthesis makes the optimal vector of cost function minimum；
Finally, three-level inverter is controlled using two obtained vectors and its corresponding duty ratio.
Specifically, the value of λ is 0.1 in formula (8).
Preferably, be not in the switching between N and P when switching in order to avoid adjacent sectors on off state, using small arrow
Implementation method in quantity set exports two vector switch sequences, i.e., small vector is placed among on off sequence, by zero vector/middle arrow
Amount/big vector action time decile is on both sides.
Compared with prior art, the present invention having the following advantages that and advantageous effect：
The present invention is on the basis of Model Predictive Control, using the model prediction power control based on two Vector modulations, phase
Than in traditional three-level inverter Model Predictive Control, realizing constant switching frequency control, two capacitances of active balance
Mid-point voltage, improve the performance of three-level inverter, reduce the harmonic content of output current, relative to predicting optimal to open
Sequence direct Power Control and modulation pattern PREDICTIVE CONTROL are closed, reduces switching number, reduces a large amount of operand, is saved
The about computing resource of control chip.
Description of the drawings
Fig. 1 is three level grid-connected inverter circuit diagrams.
Fig. 2 is three-level inverter space voltage vector figure.
Fig. 3 is three-level inverter space vector sector figure.
Fig. 4 is the geometric interpretation of the cost function J when desired voltage vector is between two vectors.
The geometric interpretation of cost function J when Fig. 5 is except desired voltage vector is located at two vectors.
Fig. 6 is that desired voltage vector and the geometry of small sector centers vector contact.
Fig. 7 is the three-level inverter model prediction power control system flow chart based on two Vector modulations.
Fig. 8 is the dynamic of inverter output line voltage in the model prediction power control system emulation based on two Vector modulations
Response.
Fig. 9 is the dynamic response of power grid line current in the model prediction power control system emulation based on two Vector modulations.
Figure 10 is electric network active and idle dynamic in the model prediction power control system emulation based on two Vector modulations
Response.
Figure 11 is the dynamic of the DC capacitor voltage of the model prediction power control system emulation based on two Vector modulations
Response.
Specific implementation mode
Present invention will now be described in further detail with reference to the embodiments and the accompanying drawings, but embodiments of the present invention are unlimited
In this.
Embodiment 1
In Fig. 1, give three level grid-connected inverter circuit diagrams, three-level three-phase inverter by filter inductance L with
And equivalent resistance R is connected with power grid.
In fig. 2, give 27 on off states corresponding space voltage vector, each on off state corresponds to sound
The voltage vector for the inverter output answered.
When inverter switching states are viWhen, the voltage vector of three-level inverter output is ui(uαi,uβi), three level are inverse
Become the output voltage vector u of deviceiIt can be acquired by grid line voltage vector e, line current vector i and inductance L and resistance R：
In formula (1), by ignoring the resistance of filter, converted by Clark, it can be static to two-phase by equation transform
Under coordinate system α β：
Wherein, (eα,eβ) and (iα,iβ) represent network voltage and electric current under static two phase coordinate systems α β.
By taking three-phase voltage as an example, Clark transformation for mula is as follows：
Wherein, eαAnd eβBetween have following relationship：
Wherein, E indicates that grid voltage amplitude, ω indicate electrical angular speed.
Instantaneous active power and reactive power can be obtained by following formula at two-phase stationary coordinate system α β：
Wherein, P is represented active, and Q represents idle.It is instantaneous on convolution (2), formula (4) and two-phase stationary coordinate system α β
The formula (5) of active power and reactive power, obtains the differential of the active power and reactive power at two-phase stationary coordinate system α β
Equation is：
When inverter switching states are viWhen, the voltage that inverter is exported at static two phase coordinate systems α β is ui(uαi,
uβi), the derivative for being input to grid side active power and reactive power is expressed as fpi, fqi.So above formula can also be indicated
For：
Active power and reactive power of the three-level inverter when k-th of sampling period starts are respectively P (k), Q (k),
By two voltage vector ui,ujT is acted on respectivelyi,tjAfter time, when+1 sampling period of kth starts, it is active and it is idle can
To be written as：
If the sampling time is Ts, since each sampling period, only there are two vectors to act on, so Ts=ti+tj.Active power
P (k+1) and reactive power Q (k+1) are active and idle predicted values when starting in+1 sampling period of kth.
In conjunction with the cost function of conventional model PREDICTIVE CONTROL, when not considering the influence of mid-point voltage, can be obtained by formula (8)
Cost function J to two vector switch series model PREDICTIVE CONTROLs can be expressed as：
J=Δs P2+ΔQ2=[Pref-P(k)-fpiti-fpjtj]2+[Qref-Q(k)-fqiti-fqjtj]2 (9)
In figure 3, region division is carried out to the three-level inverter space voltage vector figure in Fig. 2, to be based on
The model prediction power control of two Vector modulations.Consider the problems of to control neutral point voltage balance to the end, when on off sequence is by two
When a on off state composition, it is necessary to include the on off state of a small vector, the on off sequence of each small sector is as shown in table 1.
Wherein null vector includes three on off states (PPP, OOO and NNN), replaces opening for three all null vectors with OOO herein
Off status is left 25 on off states.For traditional optimizing strategy, need to carry out 48 calculating cycles to acquire most
Excellent two vector, and the optimizing strategy of the model prediction power control based on two Vector modulations only needs to carry out 18 calculating cycles,
And the calculating time of each calculating cycle is almost equal with Model Predictive Control.
The two vector switch combined sequences of 10 two small sectors of table
| Sector | On off sequence |
| I | POO-PNN,ONN-PNN,OOO-POO,OOO-ONN,POO-PNO,ONN-PNO |
| II | POO-PNN,ONN-PNN,OOO-POO,OOO-ONN,POO-PON,ONN-PON |
| III | PPO-PPN,OON-PPN,OOO-ONN,OOO-PPO,OON-PON,PPO-PON |
| IV | PPO-PPN,OON-PPN,OOO-ONN,OOO-PPO,OON-OPN,PPO-OPN |
| V | OPO-NPN,NON-NPN,OOO-OPO,OOO-NON,OPO-OPN,NON-OPN |
| VI | OPO-NPN,NON-NPN,OOO-OPO,OOO-NON,OPO-NPO,NON-NPO |
| VII | OPP-NPP,NOO-NPP,OOO-OPP,OOO-NOO,OPP-NPO,NOO-NPO |
| VIII | OPP-NPP,NOO-NPP,OOO-OPP,OOO-NOO,OPP-NOP,NOO-NOP |
| IX | OOP-NNP,NNO-NNP,OOO-OOP,OOO-NNO,OOP-NOP,NNO-NOP |
| X | OOP-NNP,NNO-NNP,OOO-OOP,OOO-NNO,OOP-ONP,NNO-ONP |
| XI | POP-PNP,ONO-PNP,OOO-POP,OOO-ONO,POP-ONP,ONO-ONP |
| XII | POP-PNP,ONO-PNP,OOO-POP,OOO-ONO,POP-PNO,ONO-PNO |
Given active power and reactive power are respectively Pref, QrefIf working as perfect switch stateAct on tri-level inversion
When device, output voltage vector isAnd inverter output power is equal to P when+1 sampling period of kth startsref,
Qref, the variable quantity of active power and reactive power within+1 sampling period of kth is respectively：
By formula (10), formula (6) and formula (7) substitute into formula (9) and can obtain：
In formula, χi=ti/Ts, χj=tj/Ts, and 0≤χi≤ 1, χi+χj=1.
In Fig. 4, output vector uiWith ujBetween line be lij, due to ur=uiχi+ujχjAnd χi+χj=1, so working as ui
With ujWhen change in duty cycle, urIn uiWith ujThe straight line l constitutedijUpper variation.With urBetween line be l',With urDistance
It is minimized as dij.WhenWhen among two vectors, in lijIt is minimized d when vertical with l'i。
In Figure 5, if givenThe case where when not among two vectors.At this point, in urWith uiOr ujIt is taken when equal
Minimum value dij.The cost function acquirement minimum value of formula (11) is as a result,：
Therefore, to export optimal two vector switch sequence, can first to the small sector residing for desired output voltage vector into
Row judges, you can obtains small sector where optimal two vector switch sequence.
In figure 6,In I sector IaWith Section II sector IbWhen the big sector of synthesis, cIaIt is the small sector I of IaIn
The heart, cIbIt is the small sector I of Section IIbCenter, dIaAnd dIbIt is respectivelyTo cIaWith to cIbDistance.SoResiding small sector can
To pass throughIt is obtained to the distance of this small sector centers.In figure 6, whenIn IbWhen sector,To IbCenter cIbDistance
It is less than IaCenter cIaDistance.Calculation formula to vector centre distance is：
Wherein, small sector output center voltage vector is：
In formula, (uα0,uβ0) it is the zero vector for constituting sector, (uαm,uβm) it is middle vector, (uαl,uβl) it is long vector.
The active power of the corresponding output center vector of formula (14) and the change rate of reactive power are：
So when not considering capacitance neutral point voltage balance, select the cost function J ' of small sector for：
J '=[Pref-P(k)-fpcTs]2+[Qref-Q(k)-fqcTs]2 (16)
Behind small sector where finding out desired output voltage vector, need to account for each the optimal of two vectorial combinations in small sector
Empty ratio is calculated, and the action time of two of which vector is respectively tiAnd tj, tiIt can be by enabling cost function J to tiDerivation
It obtains：
Enable dJ/dti=0 obtains calculating tiFormula be：
Ensure 0≤t simultaneouslyi≤Ts.In addition, by Ts=ti+tjObtain tj=Ts-ti。
In the cost function for selecting optimal two vector switch sequence, neutral point voltage balance, two capacitance C are considered1, C2's
Voltage difference is：
Wherein, uo=uc2-uc1For the voltage difference of bus capacitor, C is the size of two capacitances of DC side, viabcFor inverter
On off state, tiIt is the corresponding effect duration of on off state, | viabc|={ | via|,|vib|,|vic|}T,vix(x=a, b, c)
∈ { -1,0,1 }, iabcIt is the line current and i of connected systemabc={ ia,ib,ic}。
Consider capacitance neutral point voltage balance, find out in small sector the optimal two vector switch sequence in a switch periods,
Defining cost function J " is：
J "=[Pref-P(k)-fpiti-fpjtj]2+[Qref-Q(k)-fqiti-fqjtj]2+λ|uo(k+1)| (20)
Wherein the value of λ is 0.1, and being found out from above-mentioned result of calculation makes cost function be minimized corresponding two arrows
Amount, according to the corresponding duty ratio of two vector switch sequences, synthesis makes the optimal vector of cost function minimum.
By analysis above, the first step of the model prediction power control based on two Vector modulations is first carried out below, is taken
The center vector of small sector calculates the active-power P of+1 start time in sampling period of kthi(k+1) and reactive power Qi(k+
1) it, then brings first cost function J ' into and acquires small sector where optimal two vector switch sequence.For seeking optimal two vector
The formula of small sector is as follows where on off sequence：
After finding out the sector where optimal two vector switch sequence, second step is carried out, by the on off sequence in corresponding sector
It brings into second cost function J ", the corresponding on off sequence of cost function minimum value is optimized switching sequence.For asking most
The formula of excellent two vector switch sequence is as follows：
Optimal two vector switch of three-level inverter is acquired using the model prediction power control based on two Vector modulations
Sequence and its action time, and then three-level inverter switching device is controlled.When reality output, due on off state N
It is extremely complex to the switching between P, be not in the switching between N and P when switching in order to avoid adjacent sectors on off state, adopt
Two vector switch sequences are exported with the implementation method that small vector is concentrated.Small vector is placed among on off sequence, by zero vector/
Middle vector/big vector action time decile is on both sides.This control strategy realizes constant switching frequency control, active balance
The mid-point voltage of two capacitances reduces the harmonic content of output current, relative to prediction optimized switching sequence Direct Power control
System and modulation pattern PREDICTIVE CONTROL, reduce a large amount of operand, have saved the computing resource of control chip.
In the figure 7, the three-level inverter model prediction power control system flow chart of two Vector modulations is given.Program
It is summarized as follows：First, it finds out the center vector of 12 small sectors and by its substitution formula (15), finds out corresponding active power and nothing
Work(power conversion rate, then substitute into first cost function J ', obtain the center vector for enabling cost function J ' reach minimum value and it
The sector at place；Then, 6 two vector switch sequence v in the sector obtained in the first step are calculatedi(i=1~6) and most
Excellent duty ratio, then second cost function J " is substituted into, obtain the optimal two vector switch sequence for enabling cost function J " reach minimum value
Row, the switching device that obtained optimized switching sequence and its duty ratio corresponding finally are used to control inverter work, it is made to have
Work(power and reactive power track reference power, and DC side mid-point voltage can be balanced.
Wherein, uj1And uj2For the output vector of on off sequence in small sector, tj1And tj2It is their corresponding duty ratios,
Remaining mark meaning is identical with formula.
Three-level inverter model prediction work(based on two Vector modulations is built using simulation software MATLAB/Simulink
Rate control system carries out simulation study, and wherein simulation system parameters are as shown in table 2.
2 systematic parameter of table
| Parameter | Value |
| Filter inductance L | 6mH |
| DC bus capacitor C | 4700uF |
| DC voltage | 380V |
| Power grid phase voltage | 127V |
| Mains frequency | 50Hz |
| Sample frequency | 10kHz |
| Switching frequency | 10kHz |
| Dead time | 3us |
| With reference to active power | 3.5kW |
| With reference to reactive power | 0kVar |
By emulation, the model prediction power control based on two Vector modulations is provided to three-level three-phase gird-connected inverter
Control performance.In emulation, at the time of 10ms, by three level grid-connected inverters it is given with reference to active power from 0 promoted to
3.5kW。
In fig. 8, inverter output line in the model prediction power control system emulation based on two Vector modulations is given
The dynamic response of voltage；In fig.9, grid line in the model prediction power control system emulation based on two Vector modulations is given
The dynamic response of electric current；In Fig. 10, power grid in the model prediction power control system emulation based on two Vector modulations is given
Active and idle dynamic response；In fig. 11, the model prediction power control system emulation based on two Vector modulations is given
DC capacitor voltage dynamic response.The model prediction based on two Vector modulations is can be seen that from simulation result above
Power control system not only reduces switching number and calculating cycle, is effectively saved computing resource, and can compare
Given active power and reactive power are tracked well, reduces the ripple in alternating current, balance mid-point voltage.
The above embodiment is a preferred embodiment of the present invention, but embodiments of the present invention are not by above-described embodiment
Limitation, it is other it is any without departing from the spirit and principles of the present invention made by changes, modifications, substitutions, combinations, simplifications,
Equivalent substitute mode is should be, is included within the scope of the present invention.
Claims (4)
1. the three-level inverter model prediction Poewr control method based on two Vector modulations, which is characterized in that including：For three
27 all on off states are divided into 12 small sectors by level three-phase grid-connected inverter on the basis of traditional 6 big sectors；
The first step includes the small sector where desired output voltage vector with first cost function selection, then passes through second cost
Optimal two vector switch sequence is selected in the small sector that function obtains in the first step, finally utilizes three-level inverter selection
The corresponding on off state of two vectors controls the device for power switching of inverter according to corresponding duty ratio.
2. the three-level inverter model prediction Poewr control method according to claim 1 based on two Vector modulations,
It is characterized in that, is as follows：
Under the influence of negligible resistance, find out in three phase network at static two phase coordinate systems α β, active power and reactive power
The differential equation：
Wherein, (eα,eβ) and (iα,iβ) network voltage and electric current under static two phase coordinate systems α β are represented, L is alternating current filter
Inductance, ω indicate that electrical angular speed, P represent active power, and Q represents reactive power, when inverter switching states are viWhen, inversion
The voltage that device is exported at static two phase coordinate systems α β is ui(uαi,uβi), it is input to grid side active power and reactive power
Derivative is expressed as fpi,fqi, so above formula can also be expressed as：
Assuming that active power and reactive power of the three-level inverter when k-th of sampling period starts are respectively P (k), Q (k),
By two voltage vector voltage vector ui,ujT is acted on respectivelyi,tjAfter time, when+1 sampling period of kth starts, inversion
Device output active power be with reactive power predicted value：
If the sampling time is Ts, since each sampling period, only there are two vectors to act on, so Ts=ti+tj；
It takes zero vector, the middle big vector of vector sum to form the center of small sector respectively, is distinguished using this 12 centrally located vectors
Calculate the active-power P (k+1) and reactive power Q (k+1) of+1 start time in sampling period of kth；A cost function is defined,
At this moment sector where finding out the center vector for making cost function minimum in result of calculation does not consider that capacitance mid-point voltage is flat first
Weighing apparatus, defining cost function J ' is：
J '=[Pref-P(k)-fpcTs]2+[Qref-Q(k)-fqcTs]2 (4)
Wherein, PrefIt is given active power value, QrefIt is given reactive power value, and fpc,fqcIt is output center vector pair
The change rate of the active power and reactive power answered finds out the center vector for making cost function J ' minimums from above-mentioned result of calculation
The sector at place, then the sector is sector where required two vectors；
In seeking small sector before optimal two vector switch sequence, first each the optimal of two vectorial combinations in small sector is accounted for
Empty ratio is calculated, and the action time of two of which vector is respectively tiAnd tj, tiIt can be by enabling cost function J to tiDerivation,
And it is enabled to be obtained equal to 0, defining cost function J is：
J=Δs P2+ΔQ2=[Pref-P(k)-fpiti-fpjtj]2+[Qref-Q(k)-fqiti-fqjtj]2 (5)
It obtains calculating tiFormula be：
In addition, by Ts=ti+tjObtain tj=Ts-ti；
In cost function, consider that neutral point voltage balance, mid-point voltage equation are：
Wherein, uo=uc2-uc1For the voltage difference of bus capacitor, C is the size of two capacitances of DC side, viabcFor opening for inverter
Off status, tiIt is the corresponding effect duration of on off state, | viabc|={ | via|,|vib|,|vic|}T,vix(x=a, b, c) ∈-
1,0,1 }, iabcIt is the line current and i of connected systemabc={ ia,ib,ic}；
Consider capacitance neutral point voltage balance, finds out optimal two vector switch sequence, definition in a switch periods in small sector
Cost function J " is：
J "=[Pref-P(k)-fpiti-fpjtj]2+[Qref-Q(k)-fqiti-fqjtj]2+λ|uo(k+1)| (8)
Being found out from above-mentioned result of calculation makes cost function be minimized corresponding two vectors, is accounted for according on off sequence is corresponding
Empty ratio, synthesis make the optimal vector of cost function minimum；
Finally, three-level inverter is controlled using two obtained vectors and its corresponding duty ratio.
3. the three-level inverter model prediction Poewr control method according to claim 2 based on two Vector modulations,
It is characterized in that, the value of λ is 0.1 in formula (8).
4. the three-level inverter model prediction Poewr control method according to claim 2 based on two Vector modulations,
It is characterized in that, is not in the switching between N and P when switching in order to avoid adjacent sectors on off state, is concentrated using small vector
Implementation method export two vector switch sequences, i.e., small vector is placed among on off sequence, by zero vector/middle vector/big arrow
Action time decile is measured on both sides.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810454450.6A CN108599605B (en) | 2018-05-14 | 2018-05-14 | Three-level inverter model prediction Poewr control method based on two Vector modulations |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810454450.6A CN108599605B (en) | 2018-05-14 | 2018-05-14 | Three-level inverter model prediction Poewr control method based on two Vector modulations |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108599605A true CN108599605A (en) | 2018-09-28 |
| CN108599605B CN108599605B (en) | 2019-10-18 |
Family
ID=63637090
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810454450.6A Active CN108599605B (en) | 2018-05-14 | 2018-05-14 | Three-level inverter model prediction Poewr control method based on two Vector modulations |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108599605B (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110868097A (en) * | 2019-12-17 | 2020-03-06 | 中南大学 | Two-vector model prediction control method for reducing steady-state tracking error |
| CN110994616A (en) * | 2019-12-02 | 2020-04-10 | 湘潭大学 | Control method for direct current component of predicted power of grid-connected inverter model |
| CN111030486A (en) * | 2019-12-06 | 2020-04-17 | 合肥工业大学 | Non-parameter finite set model prediction control method of three-level grid-connected inverter |
| CN111416539A (en) * | 2020-04-24 | 2020-07-14 | 山东大学 | Model prediction control method and system for three-level grid-connected converter |
| CN111654064A (en) * | 2020-06-23 | 2020-09-11 | 广东电网有限责任公司电力科学研究院 | Control method and related device of virtual synchronous generator |
| CN112217410A (en) * | 2020-11-17 | 2021-01-12 | 中南大学 | Fault-tolerant control method and system for open-circuit fault of three-level inverter |
| CN112615557A (en) * | 2020-12-21 | 2021-04-06 | 上海交通大学 | Frequency-determining method for three-level grid-connected inverter limited control set model prediction |
| CN113271028A (en) * | 2021-06-03 | 2021-08-17 | 山东大学 | Prediction control method for reconstructing neutral point balance of topology after three-level inverter fault |
| CN113285638A (en) * | 2021-05-26 | 2021-08-20 | 盐城工学院 | Power control method and system for wind driven generator rotor side converter |
| CN113437894A (en) * | 2021-05-19 | 2021-09-24 | 中南大学 | Common-mode voltage suppression method for three-phase eight-switch inverter |
| CN113992095A (en) * | 2021-09-30 | 2022-01-28 | 江苏大学 | Low-complexity direct power control method for dual three-phase permanent magnet synchronous generator PMSG model prediction |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103036460A (en) * | 2012-11-26 | 2013-04-10 | 天津大学 | Model prediction control method for three-level voltage-source-type converter |
| CN104300817A (en) * | 2014-09-02 | 2015-01-21 | 安徽启光能源科技研究院有限公司 | T-type three-level SVPWM control method in power conversion system |
| CN104779826A (en) * | 2015-04-03 | 2015-07-15 | 西安理工大学 | Common-mode voltage suppression method for non-isolated T-shaped tri-level photovoltaic grid-connected inverter |
| US20170160760A1 (en) * | 2015-12-07 | 2017-06-08 | Hamilton Sundstrand Corporation | Model predictive control optimization for power electronics |
| CN106972773A (en) * | 2017-04-14 | 2017-07-21 | 华南理工大学 | A kind of three level grid-connected inverter constant switching frequency model predictive control methods |
| CN107104604A (en) * | 2017-04-14 | 2017-08-29 | 华南理工大学 | A kind of three level grid-connected inverter model prediction direct Power Control methods |
| CN107134939A (en) * | 2017-06-02 | 2017-09-05 | 华南理工大学 | A kind of three level grid-connected inverter dual models prediction direct Power Control method |
-
2018
- 2018-05-14 CN CN201810454450.6A patent/CN108599605B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103036460A (en) * | 2012-11-26 | 2013-04-10 | 天津大学 | Model prediction control method for three-level voltage-source-type converter |
| CN104300817A (en) * | 2014-09-02 | 2015-01-21 | 安徽启光能源科技研究院有限公司 | T-type three-level SVPWM control method in power conversion system |
| CN104779826A (en) * | 2015-04-03 | 2015-07-15 | 西安理工大学 | Common-mode voltage suppression method for non-isolated T-shaped tri-level photovoltaic grid-connected inverter |
| US20170160760A1 (en) * | 2015-12-07 | 2017-06-08 | Hamilton Sundstrand Corporation | Model predictive control optimization for power electronics |
| CN106972773A (en) * | 2017-04-14 | 2017-07-21 | 华南理工大学 | A kind of three level grid-connected inverter constant switching frequency model predictive control methods |
| CN107104604A (en) * | 2017-04-14 | 2017-08-29 | 华南理工大学 | A kind of three level grid-connected inverter model prediction direct Power Control methods |
| CN107134939A (en) * | 2017-06-02 | 2017-09-05 | 华南理工大学 | A kind of three level grid-connected inverter dual models prediction direct Power Control method |
Non-Patent Citations (2)
| Title |
|---|
| YONG YANG ET AL.: "Model predictive control method to reduce common-mode voltage and balance the neutral-point voltage in three-level T-type inverter", 《2016 IEEE APPLIED POWER ELECTRONICS CONFERENCE AND EXPOSITION (APEC)》 * |
| 冯腾等: "基于合成中矢量的三电平中点平衡预测控制", 《电力电子技术》 * |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110994616B (en) * | 2019-12-02 | 2021-04-27 | 湘潭大学 | Control method for direct current component of predicted power of grid-connected inverter model |
| CN110994616A (en) * | 2019-12-02 | 2020-04-10 | 湘潭大学 | Control method for direct current component of predicted power of grid-connected inverter model |
| CN111030486A (en) * | 2019-12-06 | 2020-04-17 | 合肥工业大学 | Non-parameter finite set model prediction control method of three-level grid-connected inverter |
| CN110868097A (en) * | 2019-12-17 | 2020-03-06 | 中南大学 | Two-vector model prediction control method for reducing steady-state tracking error |
| CN110868097B (en) * | 2019-12-17 | 2021-07-09 | 中南大学 | Two-vector model prediction control method for reducing steady-state tracking error |
| CN111416539A (en) * | 2020-04-24 | 2020-07-14 | 山东大学 | Model prediction control method and system for three-level grid-connected converter |
| CN111416539B (en) * | 2020-04-24 | 2021-08-06 | 山东大学 | Model prediction control method and system for three-level grid-connected converter |
| CN111654064A (en) * | 2020-06-23 | 2020-09-11 | 广东电网有限责任公司电力科学研究院 | Control method and related device of virtual synchronous generator |
| CN112217410A (en) * | 2020-11-17 | 2021-01-12 | 中南大学 | Fault-tolerant control method and system for open-circuit fault of three-level inverter |
| CN112615557A (en) * | 2020-12-21 | 2021-04-06 | 上海交通大学 | Frequency-determining method for three-level grid-connected inverter limited control set model prediction |
| CN113437894A (en) * | 2021-05-19 | 2021-09-24 | 中南大学 | Common-mode voltage suppression method for three-phase eight-switch inverter |
| CN113285638A (en) * | 2021-05-26 | 2021-08-20 | 盐城工学院 | Power control method and system for wind driven generator rotor side converter |
| CN113285638B (en) * | 2021-05-26 | 2022-05-17 | 盐城工学院 | Power control method and system for wind driven generator rotor side converter |
| CN113271028A (en) * | 2021-06-03 | 2021-08-17 | 山东大学 | Prediction control method for reconstructing neutral point balance of topology after three-level inverter fault |
| CN113271028B (en) * | 2021-06-03 | 2022-05-17 | 山东大学 | Prediction control method for reconstructing neutral point balance of topology after three-level inverter fault |
| CN113992095A (en) * | 2021-09-30 | 2022-01-28 | 江苏大学 | Low-complexity direct power control method for dual three-phase permanent magnet synchronous generator PMSG model prediction |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108599605B (en) | 2019-10-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108599605B (en) | Three-level inverter model prediction Poewr control method based on two Vector modulations | |
| CN107134939B (en) | A kind of three level grid-connected inverter dual models prediction direct Power Control method | |
| CN103036462B (en) | Model prediction control method of voltage source type rectifier when network voltage is unbalanced | |
| Lehn | Exact modeling of the voltage source converter | |
| CN105391271B (en) | Low frequency rapid finite collection model predictive control method applied to power electronic system | |
| CN105897030B (en) | A kind of dead beat determines frequency model predictive control method, apparatus and system | |
| CN105375804A (en) | Model prediction current control method based on NPC topology grid connected inverter under asymmetric voltage | |
| CN103956919A (en) | Simplified model forecasting control method of network voltage unbalance three-level rectifier | |
| CN101951174A (en) | Constant-frequency direct power control method for PWM converter under condition of power grid voltage imbalance | |
| CN106291150B (en) | A kind of electrochemical capacitor life calculation method based on ripple analysis | |
| CN103560691B (en) | A kind of method of non-angular computing SVPWM and grid-connected inverting system | |
| Shahnazian et al. | Interfacing modular multilevel converters for grid integration of renewable energy sources | |
| CN109787491A (en) | Three-phase Vienna rectifier based on Virtual shipyard predicts direct Power Control method | |
| CN105515430A (en) | Control method of three-phase grid-connected inverter | |
| CN105071677A (en) | Current prediction control method for two-level three-phase grid-connected inverter | |
| CN108696170B (en) | Frequency finite aggregate model predictive control method is determined for two level three-phase inverters | |
| CN111614282B (en) | Vector sector positioning method, local optimization model prediction control method and device | |
| CN107769259B (en) | A kind of inverter current forecast Control Algorithm based on discrete averaging model | |
| CN108205595B (en) | PSCAD double-fed wind turbine simulation model system suitable for harmonic analysis | |
| CN105375514A (en) | Limit switch state prediction calculation method and system | |
| CN107888101A (en) | A kind of grid-connected NPC three-level inverters modulator approach | |
| CN110297446B (en) | Multi-vector rapid model prediction control method under non-ideal power grid condition | |
| Xu et al. | Model predictive duty cycle control for three‐phase Vienna rectifiers | |
| CN105322818A (en) | Control method of three-phase PWM (pulse width modulation) rectification based on novel model prediction control | |
| CN115693745A (en) | Flexible low-frequency power transmission system control method and device |
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 |