CN109904881A - A kind of cascade microgrid power based on adaptive simulated capacitance divides equally control method - Google Patents
A kind of cascade microgrid power based on adaptive simulated capacitance divides equally control method Download PDFInfo
- Publication number
- CN109904881A CN109904881A CN201910292944.3A CN201910292944A CN109904881A CN 109904881 A CN109904881 A CN 109904881A CN 201910292944 A CN201910292944 A CN 201910292944A CN 109904881 A CN109904881 A CN 109904881A
- Authority
- CN
- China
- Prior art keywords
- inverter
- cascade
- capacitance
- voltage
- output
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 38
- 230000003044 adaptive effect Effects 0.000 title claims abstract description 18
- 239000003990 capacitor Substances 0.000 claims description 8
- 230000005611 electricity Effects 0.000 claims description 7
- 125000002619 bicyclic group Chemical group 0.000 claims description 3
- 230000001939 inductive effect Effects 0.000 claims description 3
- 238000007665 sagging Methods 0.000 description 53
- 238000011217 control strategy Methods 0.000 description 12
- 230000001965 increasing effect Effects 0.000 description 10
- 238000010586 diagram Methods 0.000 description 8
- 230000008859 change Effects 0.000 description 7
- 238000004088 simulation Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 238000004891 communication Methods 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 5
- 230000008447 perception Effects 0.000 description 4
- 230000006870 function Effects 0.000 description 3
- 230000002411 adverse Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 230000006641 stabilisation Effects 0.000 description 2
- 238000011105 stabilization Methods 0.000 description 2
- 238000012795 verification Methods 0.000 description 2
- NAWXUBYGYWOOIX-SFHVURJKSA-N (2s)-2-[[4-[2-(2,4-diaminoquinazolin-6-yl)ethyl]benzoyl]amino]-4-methylidenepentanedioic acid Chemical compound C1=CC2=NC(N)=NC(N)=C2C=C1CCC1=CC=C(C(=O)N[C@@H](CC(=C)C(O)=O)C(O)=O)C=C1 NAWXUBYGYWOOIX-SFHVURJKSA-N 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000004069 differentiation Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Inverter Devices (AREA)
Abstract
The invention discloses a kind of cascade microgrid powers based on adaptive simulated capacitance to divide equally control method, and cascade micro-capacitance sensor includes multiple inverters, in the output end setting of cascade micro-capacitance sensor simulated capacitance in parallel；Simulated capacitance CxMeet following formula:The cascade microgrid power based on adaptive simulated capacitance divides equally control method and is conducive to power-sharing, and easily controllable.
Description
Technical field
The present invention relates to a kind of cascade microgrid powers based on adaptive simulated capacitance to divide equally control method.
Background technique
So-called sagging control is exactly selection frequency droop characteristic (Droop similar with conventional electric generators
Character the) control mode as micro- source obtains stable frequency by the sagging control of P/f and the sagging control of Q/V respectively
Rate and voltage, this control method are respectively controlled the active power and reactive power of micro- source output in microgrid, are not necessarily to
Communication-cooperation between unit realizes the target of micro- source plug and play and equity control, ensure that under isolated island electric power in micro-capacitance sensor
The unification of balance and frequency, has the characteristics that simple and reliable.As the mankind are to the growing of energy demand, renewable energy and
Distributed generation resource (distributed generator, DG) technology receives the extensive concern of domestic and foreign scholars.Micro-capacitance sensor can
It coordinates and manages different types of distribution to decline source, is the important channel that distributed energy efficiently utilizes.
To improve system reliability and redundancy, the dependence to communication is reduced, voltage source inverter mostly uses in micro-capacitance sensor
Sagging control, to realize effectively dividing equally to bearing power.In micro-capacitance sensor in parallel, sagging control has been applied to off-network and simultaneously
In the model of net.In view of micro- source has dispersibility and diversity, it is difficult to use the parallel technology based on high-bandwidth communication, therefore
Sagging control based on no control interconnection is widely used.Sagging control is based on conventional synchronization generator power supply external characteristics
P-f and Q-V droop control method, between traditional power grid it is with higher compatibility and attract attention.The sagging control principle base
In line impedance based on perception it is assumed that still it is medium/low press-fitting power grid micro-grid system in, line impedance is with resistive
It is main, the sagging control performance in micro- source is had adverse effect on.Therefore, there is document by introducing perceptual virtual impedance, propose more
The bicyclic sagging control strategy of the voltage and current of inverter parallel micro-capacitance sensor exports electricity by subtracting micro- source in voltage close loop instructs
The mode of the pressure drop on perceptual virtual impedance is flowed, realizes the adjusting to micro- source equivalent output impedance, limiting circuitry impedance is to power
Influence respectively.Due to the introducing of virtual impedance, there are problems that micro- source output terminal Voltage Drop in the case of isolated island.For this purpose, having
Document is further improved, and is made virtual impedance bring Voltage Drop become to realize output end Q-V droop characteristic, is deleted sagging control
In Q-V outer ring, solve the problems, such as because of virtual impedance bring Voltage Drop.There is document to improve from sagging control ring,
The influence because of line impedance difference to reactive power is analyzed, differentiation element is added to droop control device Q-V ring, to compensate power
Calculate bring control lag.
In recent years, more level, the web development of inverter technology makes inverter output voltage reach higher voltage water
Gentle more preferably quality of voltage.Cascaded H-bridges are a kind of most typical boosting inverter methods due to modularization, high flexibility, most
It is first applied to multi-level converter, more based on level number, the voltage harmonic component of output is few, and switching loss is also greatly reduced,
It is more in the comparison that the photovoltaic system of high-power is applied.There is researcher to realize for cascade connection multi-level using centralized control
Power distribution and SOC balance between unit, however there are some disadvantages, such as high-speed communication to reduce the stabilization of system for this control
Property, because leading to poor dynamic property during load transients variation.Pervious work is concentrated mainly on cascaded inverter unit
In power quality.Wherein the power-sharing between unit is seldom mentioned.
In low pressure micro-capacitance sensor, cascade up again after each inverter is accessed output filter, what this mode was constituted
Inverter cascading topological structure can provide better stability for micro-capacitance sensor, but go to realize unit using centralized control
Between power equalization.In the case of off-network, have document towards cascade micro-capacitance sensor in sagging control application, derive it is sagging control and
Relationship between load has been put forward for the first time the distributing control sagging based on inverse power factor, has realized intermodule without communication function
Rate balance policy, but this control strategy is only applicable to load into perception, and function can all occur in capacitance-resistance or pure resistor load
Rate does not divide equally problem.There is document in cascade micro-capacitance sensor, proposes and remove to realize inverter list in grid-connected situation using sagging control
Power balance control between member, each unit go to realize power equalization problem according to the state of itself, analyze under grid-connect mode
The stability of whole system.There is document for the difference of the MPPT of each unit of photovoltaic panel, by adjusting sagging control coefrficient, energy
Enough maximum tracking that MPPT is realized in grid-connected cascaded inverter, enable each unit to export the maximum power of itself.And have
Document is then the difference for battery SOC, by the sagging control coefrficient of adjusting, realizes battery in grid-connected cascaded inverter
The equilibrium of SOC.There is document by modifying sagging control coefrficient, proposes the sagging control of f-P/Q, loaded in capacitance resistance load and resistance sense
In the case of, equal realization power equalizations, and in pure resistor load, the characteristic root of module be entirely zero or be all bear it is infinite
Greatly, it may appear that power is not divided equally.
The studies above shows in the vertical control strategy of power-sharing of existing off-network cascade micro-capacitance sensor that load characteristic is closed closely
It is power-sharing effect, the power-sharing of intermodule is realized by modifying sagging coefficient in droop control device, but is loaded
It always will appear a singular point and do not meet existing sagging control, it is difficult to guarantee the power-sharing under arbitrary load quality event.So
And in practice due to engineering, load characteristic is difficult to previously given, therefore studies off-network under arbitrary load quality event and cascades micro- electricity
The power-sharing method of net is very necessary.
The power-sharing of off-network cascaded inverter controls analysis
Cascaded inverter is by the effective use to low-voltage direct distributed generation resource (DG), and low-voltage dc power supply is without change
Depressor is applied in middle pressure AC power supply system, and distributed generation resource is made to obtain better utilization rate.
The equivalent model of off-network cascaded inverter
Fig. 1 gives the topological diagram of off-network cascade Mach-Zehnder interferometer, and topological diagram can be seen that the output wattful power of i-th of inverter
Rate PiAnd reactive power Qi。
And ViAnd θiIt is the output voltage and phase angle of i-th of module.Ac bus voltageIt is the total of each module
With.
According to equation (1)-(2), it can be deduced that the active power of output P of i-th of inverteriAnd reactive power Qi
θioadIt is the phase angle of load end, ZloadIt is the amplitude of load end.
According to equation (3-4) can must cascade micro-capacitance sensor output active power and reactive power and output voltage amplitude and
FrequencyIt is all related, and because the variation of load impedance angle determines the form of the sagging governing equation of power.In perception
Under complex situations, micro-source inverter can pass through own phase θiActive power output is adjusted, by adjusting itself voltage amplitude
Value ViTo adjust the output of reactive power.Due to cascade micro-capacitance sensor in flow through each micro-source inverter electric current be it is the same, when
Contravarianter voltage instructs VrefWhen drawing definite value, the apparent energy in each micro- source is identical, as long as active power is divided equally, reactive power
Automatic realize is divided equally.To which on power-sharing control plane, the control of inverter active power of output and reactive power is solution
Coupling.Simultaneously as phase is not easy to detect, the adjusting for realizing voltage-phase indirectly is adjusted usually using frequency.Shown in table 1 successively
It is approximately perception, the approximate corresponding power expression of capacitive and sagging governing equation for load impedance angle.
The sagging governing equation expression formula of table 1
By introducing above-mentioned P- ω droop characteristic, cascade micro-capacitance sensor can realize the stable operation based on no interconnecting signal line.
The micro- source droop control method principle such as Fig. 2 proposed based on this.Micro- source output terminal voltage instruction VrefBy outer voltage according to
The P- ω droop characteristic of setting is calculated；It is given that voltage and current ring carries out tracking, and is finally realized by closed-loop control
To micro- source output terminal voltage VrefDynamically track.Micro- source equivalent can have internal resistance Z at one0(s) controlled voltage source G (s)
Vref；But Zload∠θloadIt is to guarantee that micro- sagging control module in source expires the most important condition, due to not knowing for system load information, in turn
Have an adverse effect to the sagging control effect in micro- source.
Therefore, it is necessary to which designing a kind of cascade microgrid power based on simulated capacitance divides equally control method.
Summary of the invention
Technical problem to be solved by the invention is to provide a kind of cascade microgrid powers based on adaptive simulated capacitance
Respectively control method, it is easy to implement which divides equally control method, and stablizes
Property it is high.
The technical solution of invention is as follows:
A kind of cascade microgrid power based on adaptive simulated capacitance divides equally control method, and cascade micro-capacitance sensor includes multiple
Inverter, in the output end setting of each inverter of cascade micro-capacitance sensor simulated capacitance in parallel；
The corresponding simulated capacitance C of i-th of inverterxMeet following formula:
Cx=-kQi；
K is coefficient；
QiIt is the output reactive power of each inverter；
ω is angular frequency；
ViIt is the output voltage of each inverter.The simulated capacitance C of each inverterxNumerical value is not necessarily identical, Ke Yijin
One step is clearly Cxi；In addition, corresponding different inverter, ViIt is identical, but QiIt is not necessarily identical, therefore, CxWith QiBecome
Change；Specific control, is independently to carry out double-closed-loop control to each inverter.It is bicyclic to cascade micro-capacitance sensor using voltage and current
Implement control, outer ring is voltage control loop, to improve the waveform of system output voltage, is controlled using PI；Inner ring is inductance electricity
Ring is flowed, is controlled using P.The adjusting of specific control parameter is existing mature technology.
The inverter is H bridge inverter, and the DC side (input side) of each inverter connects a direct current distribution
Power supply；And the output of each H bridge inverter is terminated with a filter；
The outlet side of multiple inverters is sequentially connected in series, and the first end of first inverter outlet side and the last one inversion
The second segment of device outlet side constitutes the net side of cascade micro-capacitance sensor, i.e., cascades up again after each inverter access output filter,
Net side is also known as the outlet side for cascading micro-capacitance sensor, for connecing load.
Have: uc=Gu(s)uref-Zu(s)i0；
CxFor the simulated capacitance of introducing, L and C are respectively the inductance and capacitor of the output side filter of inverter.
ucFor the output voltage of inverter, urefFor given voltage value, Z (s) is the output impedance of inverter, i0For inversion
The output electric current of device, KipFor the ratio value (i.e. proportionality coefficient) of electric current loop, KvpFor the ratio value (i.e. proportionality coefficient) of Voltage loop,
KviFor the integrated value (i.e. integral coefficient) of Voltage loop.Ratio value and integrated value are adjusted by PID, specific PID control
The adjusting of device processed is existing mature technology.
The utility model has the advantages that
Cascade microgrid power based on adaptive simulated capacitance of the invention divides equally control method, applies in multi-inverter
In the micro-capacitance sensor of cascade structure, load characteristic stochastic transformation can effectively be overcome to divide equally to cascade microgrid power and its stability
It influences.The stability analysis that the present invention passes through cascade micro-capacitance sensor, it is indicated that existing power-sharing method exists not in purely resistive load
Stable problem proposes the method for virtual inverter parallel capacitor, it is equal to expand power in conjunction with the architectural characteristic of cascade micro-capacitance sensor
Divide the stability range of algorithm；On this basis, the adaptive operator (Cx=-kQi that simulated capacitance changes with load characteristic is proposed
As adaptive operator), the online adaptive implementation method of simulated capacitance is given, ensure that cascade micro-capacitance sensor in arbitrary load
Under stable operation.
Power-sharing control strategy proposed by the present invention based on simulated capacitance, by inverter unit module output end
Additional shunt capacitance, makes load impedance based on capacitive, and reducing load impedance influences the performance of system, solves Voltage Drop
Problem.By theory analysis and simulation results show, this method, can in any load characteristic, especially pure resistor load
Guarantee system realizes effective power-sharing.Meanwhile for the impedance operator of constant power load, the increased virtual electricity of this aspect
Hold, can also effectively improve the stability of busbar voltage, and inhibit influence of the load sudden change to system.Finally by simulation comparison
The performance for improving front and back cascade micro-capacitance sensor is analyzed, and utilizes the experimental verification validity of proposed method.
Detailed description of the invention
Fig. 1 is off-network cascade Mach-Zehnder interferometer topological diagram；
Fig. 2 is inverter microgrid structure control schematic diagram；
Fig. 3 is parallel virtual capacitor equivalent circuit diagram；
Fig. 4 is the cascade micro-capacitance sensor closed-loop control block diagram with simulated capacitance；
Fig. 5 is the use scope schematic diagram of simulated capacitance；
Fig. 6 is that resistance sense is loaded, using the active power curves of the sagging control strategy of tradition；
Fig. 7 is that resistance sense is loaded, using the reactive capability curve of the sagging control strategy of tradition；
Fig. 8 is that resistance sense is loaded, the active power curves after increasing simulated capacitance；
Fig. 9 is that resistance sense is loaded, the reactive capability curve after increasing simulated capacitance；
Figure 10 is for capacitive load, using the active power curves of the sagging control strategy of tradition；
Figure 11 is for capacitive load, using the reactive capability curve of the sagging control strategy of tradition；
Figure 12 is the active power curves for capacitive load, after increasing simulated capacitance；
Figure 13 is the reactive capability curve for capacitive load, after increasing simulated capacitance；
Figure 14 is the reactive capability curve for pure resistor load, after increasing simulated capacitance；
Figure 15 is the active power curves for pure resistor load, after increasing simulated capacitance.
Specific embodiment
The present invention is described in further details below with reference to the drawings and specific embodiments:
Embodiment 1:
The sagging control strategy of improvement based on simulated capacitance:
To solve the problems, such as above-mentioned sagging control, there are two types of resolving ideas, a kind of thinking is by changing sagging control coefrficient
Matched load information is gone, but this needs to measure the reactive power in each inverter output power.In contrast, negative by changing
The information for carrying impedance angle, is significantly more efficient method.
By changing load impedance characteristic to guarantee the method for sagging control stability, including virtual concatenation inductance and virtual
Shunt capacitance two ways.For the mode of virtual concatenation inductance, document[3,4]The virtual impedance method of proposition can be in larger range
The equivalent output impedance of inverter is adjusted, due to the pressure drop on series connection virtual impedance, inverter is calculating output electric current
Pressure drop V on virtual impedanceDAfterwards, the voltage instruction V exported from sagging control module*It is middle by VDIt subtracts, and then after obtaining amendment
Micro- source output terminal voltage close loop instruct Vref=V*-VD.As it can be seen that using the mode of series connection virtual impedance, with virtual inductor
Increase, output voltage will appear apparent Voltage Drop problem.And inductance value is bigger, also results in the stability of system very big
Influence.In order to solve the addition due to virtual inductor, caused Voltage Drop, then need plus secondary voltage compensates, and makes system
Design complexities increase.
In order to solve because of inductance bring Voltage Drop, and the control precision of voltage is improved, the present invention is used based on virtual
The microgrid inverter control strategy of capacitor simulates the shunt capacitance characteristic of microgrid inverter output end by control algolithm,
It is equivalent to a part for simulated capacitance being regarded as load, eliminating load is the influence under pure resistance state to power-sharing, simultaneously
Improve the control precision of output voltage.
Addition based on simulated capacitance, as shown in Figure 2, the output power of corresponding each unit are also become accordingly
Change, the output power of inverter i is after addition simulated capacitance
Wherein ViAnd θiIt is the voltage and angle of each output unit respectively, and VpccAnd θpccIt is the voltage and angle of load.
It is respectively as follows: according to the active power of the available each unit in formula (5)-(6) and reactive power
Wherein | Zload| it is θ load impedance, j is the output voltage phase angle of each unit.Formula (7)-(8) are substituted into sagging control
Formula processed[10]
And ViAnd VjV can be regarded as*It carries out simplifying processing.
Small signal process is carried out to formula (10)
It can be seen from formula (11) if without simulated capacitance, sagging control can not effectively be run in pure resistance, so
And after simulated capacitance is added, as long as in virtual capacitance a certain range, it will be able to guarantee sagging control under any loading condition
Point.
Formula (11) is converted into matrix form:
The characteristic value for obtaining matrix L from formula is
λA1=0, λA2=λA3=...=λAn=n (13)
To:
It can find out from formula (14), when load is pure resistance
Wherein miFor sagging control coefrficient, n is the number of unit.Thus when load is pure resistance, corresponding feature
Root is not all 0, or infinitely great.By formula (15) it is recognized that while simulated capacitance overcomes the power-sharing in pure resistance, but by
(14) it is found that in the case that load is resistance sense, always there is any offsets the phase angle for loading resistance sense with simulated capacitance, so that
Resistance characteristic is presented in load, does not meet existing sagging control.Therefore to the simulated capacitance C of formula (14)xIt modifies, realizes empty
Quasi- capacitor it is adaptive, effectively avoid simulated capacitance and singular point that resistance sense is cancelled out each other, power made to realize power-sharing.By formula
(7-8) can be obtained:
QL=Qi+ωCVi 2 (17)
θloadIt is the phase angle of load end；
Load current are as follows:
iL=Ii∠δi-ωCxVi∠(90+δu) (19)
Formula (19) expansion is obtained:
And the amplitude of formula (20) load current are as follows:
Bring formula (18-21) into (14), it can be in the hope of because meeting condition:
sinθload|Zload|=Xload (23)
(18) (20) formula is substituted into following formula and is acquired:
ωCxXload- 1 < 0
Peer-to-peer sin θload-ωCx|Zload| ≠ 0 is analyzed:
Formula (22) substitution equation is obtained:
Formula (26) are unfolded:
Above formula (27) is normalized:
WhereinCorresponding coefficient is all smaller, can be with
Ignore the influence of its peer-to-peer.
As long as then meetingIt can be to avoid the presence of singular point；
The simulated capacitance of design is equivalent to the capacitance for increasing filter, better burning voltage, while can change negative
The information for carrying impedance angle, makes it meet the condition of existing sagging control.
Simulated capacitance parameter designing
A. stability analysis
In inverter i output end shunt capacitance Cx, it can be equivalent at the information for adjusting load end, Fig. 3 is that output end is in parallel
Capacitor CxInverter equivalent circuit, wherein Li=Xi/ ωiFor the internal resistance Z in micro- source0(s), RLoad+sLLoadFor system common load
Zload(s), due to the output impedance Z of inverter0(s) and line impedance is far smaller than load impedance, can ignore them to system
Influence.
In Practical Project, not only increase volume and cost, therefore, Ke Yitong in inverter output end true capacitor in parallel
Simulated capacitance algorithm is crossed to simulate practical shunt capacitance characteristic.Therefore, simulated capacitance is introduced, then can preferably change power frequency item
Load impedance amplitude-frequency characteristic under part.Inverter control block diagram of the present invention is as shown in Figure 4.Using voltage and current double -loop control, outer ring
It is voltage control loop, to improve the waveform of system output voltage, makes it have higher voltage output precision, controlled using PI
System, inner ring is that inductive current ring is controlled to improve the dynamic property of system using P.It is obtained by Fig. 4:
uc=Gu(s)uref-Zu(s)i0 (30)
Cx is the simulated capacitance introduced, and LC is respectively the capacitor of filter, inductance.
From formula (30-32) as can be seen that the addition of simulated capacitance is equivalent in one actual capacitance of output end parallel connection.With
The increase of simulated capacitance, reduce influence of the load impedance to system voltage.Simulated capacitance is the solution of " hard with soft generation " in engineering
Certainly mode realizes effect identical with output end increase actual capacitance.
The size that simulated capacitance is adjusted it can be seen from formula (24) (29) adaptively, is realized that intermodule power-sharing is asked
Topic.It is directly proportional to reactive power by simulated capacitance, as long as coefficient is transferred to a lesser value, simulated capacitance may be implemented and bear
What is carried is adaptive, avoids the point for making to load into resistance.It takes:
Cx=-kQi
From formula (33) as can be seen that simulated capacitance and the reactive power of output are proportional, and the mistake of simulated capacitance value
Greatly, it also will affect the stability problem of whole system, so reactive power can only lock in a certain range.That is reactive power
Simulated capacitance is added in the lesser stage；As Fig. 5 shows.
In reactive power Qi≤Q1When, simulated capacitance is added in we；Q1Value be generally and load 0.1 times of reactive power
Left and right, then the simulated capacitance being added is smaller, will not influence the stabilization of whole system.
Emulation and experimental verification
It is inverse in MATLAB/Simulink emulation platform building two in order to verify the validity of above-mentioned simulated capacitance algorithm
Become device and cascades simulation model.Using DC side source of stable pressure simulation distribution formula power supply, 5+j0.314 group inductive load is connect.Simulation parameter
As shown in the table.The sagging control of the improvement virtual impedance of the corresponding sagging control of inductance and proposition is respectively adopted.
System parameter
A. it situation one: loads as (L=1 × 10 LR-3MH, R=5 Ω)
Fig. 6-7 is traditional droop control method, is active power and reactive power waveform respectively, according to the information of load
It determines determining sagging control, realizes dividing equally for active power meter and reactive power.Fig. 8 is after then increasing simulated capacitance
Active power, as the active power of traditional droop control method.Fig. 9 is improved reactive power, and the sagging control of tradition
The reactive power of method processed is the same.It can illustrate to will not influence the biggish bearing power of inductance value using virtual impedance method and divide equally,
It can be realized cascade power-sharing problem.
B. it situation two: loads as CR (R=5 Ω, C=2 × 10-3F)
Figure 10-11 is load impedance when being capacitance characteristic, respectively active power and reactive power figure.According to load
Information determines determining sagging control, realizes dividing equally for active power meter and reactive power.Figure 12 is then to increase virtual electricity
Active power after appearance, as the active power of traditional droop control method.Figure 13 is improved reactive power, and tradition
The reactive power of droop control method is the same.It can illustrate to will not influence the power-sharing of capacitive load using virtual impedance method,
It can be realized cascade power-sharing problem.
C. it situation three: loads as pure resistance R (R=5 Ω)
Figure 14 is then that joined adaptive simulated capacitance algorithm in double -loop control, can load reactive power it is smaller
In the range of change load impedance angle, make load present capacitance-resistance feature.The characteristics of meeting existing sagging control, it can be seen that be
When pure resistance, the power-sharing between each module can be realized.
Figure 15 is the active power increased after simulated capacitance, can be realized dividing equally for active power.
It should be noted that being the active curve of 2 inverters in Fig. 6, since 2 curves are overlapped, so it seems that only
There is a curve, 2 curves in Fig. 7 are the idle curves of corresponding 2 inverters；Remaining Fig. 8-15 is similar.Abscissa table
Show simulation time, unit is the second, and ordinate indicates that the amplitude of active power or reactive power, the unit of active power are watt
The unit of spy, reactive power isVar。
In conclusion not only can be the output of system when micro-capacitance sensor uses the sagging control strategy based on simulated capacitance
Voltage meets the needs of load, but also can effectively inhibit micro-capacitance sensor harmonic wave, therefore, the virtual electricity of above-mentioned simulating, verifying
Hold the stability and validity of control emulation of hanging down.
Conclusion
In cascade micro-capacitance sensor, the micro battery for analyzing the sagging control strategy based on simulated capacitance meets the sagging spy of P-f
Property, the automatic distribution without communication system power when load variation may be implemented.Establish the sagging control plan based on simulated capacitance
Slightly, influence of the simulated capacitance control ring to system output characteristics is studied, and according to the closed loop transfer function, of inverter control system,
The stability analysis of the sagging control of simulated capacitance is carried out.The micro-capacitance sensor harmonic suppressing method of simulated capacitance is analyzed, and is carried out
The emulation of micro-capacitance sensor harmonics restraint, simulation result show that droop control method based on simulated capacitance has and inhibit harmonic wave effects,
The aberration rate of micro battery harmonic wave of output voltage reduces.
Claims (4)
1. a kind of cascade microgrid power based on adaptive simulated capacitance divides equally control method, which is characterized in that cascade micro- electricity
Net includes multiple inverters, in the output end setting of each inverter of cascade micro-capacitance sensor simulated capacitance in parallel；
The corresponding simulated capacitance C of i-th of inverterxMeet following formula:
Cx=-kQi；
K is coefficient；
QiIt is the output reactive power of each inverter；
ω is angular frequency；
ViIt is the output voltage of each inverter.
2. the cascade microgrid power according to claim 1 based on adaptive simulated capacitance divides equally control method, special
Sign is, implements control to cascade micro-capacitance sensor using voltage and current is bicyclic, outer ring is voltage control loop, to improve system output
The waveform of voltage, is controlled using PI；Inner ring is inductive current ring, is controlled using P.
3. the cascade microgrid power according to claim 1 based on adaptive simulated capacitance divides equally control method, special
Sign is:
The inverter is H bridge inverter, and the DC side (input side) of each inverter connects a direct current distributed generation resource；
And the output of each H bridge inverter is terminated with a filter；
The outlet side of multiple inverters is sequentially connected in series, and the first end of first inverter outlet side and the last one inverter are defeated
The second segment of side constitutes the net side of cascade micro-capacitance sensor out, i.e., cascades up again after each inverter access output filter, net side
The outlet side for also known as cascading micro-capacitance sensor, for connecing load.
4. the cascade microgrid power according to claim 1-3 based on adaptive simulated capacitance divides equally controlling party
Method, which is characterized in that
uc=Gu(s)uref-Zu(s)i0；
CxFor the simulated capacitance of introducing, L and C are respectively the inductance and capacitor of the output side filter of inverter.
ucFor the output voltage of inverter, urefFor given voltage value, Z (s) is the output impedance of inverter, i0For inverter
Export electric current, KipFor the ratio value of electric current loop, KvpFor the ratio value of Voltage loop, KviFor the integrated value of Voltage loop.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910292944.3A CN109904881A (en) | 2019-04-12 | 2019-04-12 | A kind of cascade microgrid power based on adaptive simulated capacitance divides equally control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910292944.3A CN109904881A (en) | 2019-04-12 | 2019-04-12 | A kind of cascade microgrid power based on adaptive simulated capacitance divides equally control method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109904881A true CN109904881A (en) | 2019-06-18 |
Family
ID=66955687
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910292944.3A Pending CN109904881A (en) | 2019-04-12 | 2019-04-12 | A kind of cascade microgrid power based on adaptive simulated capacitance divides equally control method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109904881A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110350507A (en) * | 2019-08-01 | 2019-10-18 | 华北电力大学（保定） | Direct-current micro-grid equivalent capacity determines method, apparatus and computer readable storage medium |
| CN110854909A (en) * | 2019-11-11 | 2020-02-28 | 内蒙古电力(集团)有限责任公司内蒙古电力科学研究院分公司 | Fully-dispersed self-adaptive power control method for island operation series converter |
| CN111555343A (en) * | 2020-05-07 | 2020-08-18 | 中南大学 | General distributed control method and system for cascade inverter |
| CN113433839A (en) * | 2021-06-28 | 2021-09-24 | 杭州电子科技大学 | Synchronous rectification Boost converter simulation circuit based on virtual inductor and virtual capacitor |
| CN113824160A (en) * | 2021-09-18 | 2021-12-21 | 长沙理工大学 | Adaptive virtual inductor-based micro-grid parallel inverter power regulation method |
| CN114268114A (en) * | 2021-12-20 | 2022-04-01 | 安徽农业大学 | Secondary voltage compensation method for hybrid energy storage system |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105226727A (en) * | 2015-10-12 | 2016-01-06 | 合肥工业大学 | Microgrid inverter parallel power based on simulated capacitance divides equally control method |
| CN109449999A (en) * | 2019-01-11 | 2019-03-08 | 山东大学 | Low pressure micro-capacitance sensor distributed control method and system based on adaptive virtual impedance |
-
2019
- 2019-04-12 CN CN201910292944.3A patent/CN109904881A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105226727A (en) * | 2015-10-12 | 2016-01-06 | 合肥工业大学 | Microgrid inverter parallel power based on simulated capacitance divides equally control method |
| CN109449999A (en) * | 2019-01-11 | 2019-03-08 | 山东大学 | Low pressure micro-capacitance sensor distributed control method and system based on adaptive virtual impedance |
Non-Patent Citations (1)
| Title |
|---|
| HAIZHEN XU 等: ""A reactive power sharing method based on virtual capacitor in islanding microgrid"", 《2014 INTERNATIONAL POWER ELECTRONICS CONFERENCE》 * |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110350507A (en) * | 2019-08-01 | 2019-10-18 | 华北电力大学（保定） | Direct-current micro-grid equivalent capacity determines method, apparatus and computer readable storage medium |
| CN110854909A (en) * | 2019-11-11 | 2020-02-28 | 内蒙古电力(集团)有限责任公司内蒙古电力科学研究院分公司 | Fully-dispersed self-adaptive power control method for island operation series converter |
| CN110854909B (en) * | 2019-11-11 | 2022-05-27 | 内蒙古电力(集团)有限责任公司内蒙古电力科学研究院分公司 | Fully-dispersed self-adaptive power control method for island operation series converter |
| CN111555343A (en) * | 2020-05-07 | 2020-08-18 | 中南大学 | General distributed control method and system for cascade inverter |
| NL2026118B1 (en) * | 2020-05-07 | 2021-11-23 | Univ Central South | Method and system of general decentralized control for cascaded inverters |
| CN111555343B (en) * | 2020-05-07 | 2023-06-27 | 中南大学 | Universal distributed control method and system for cascading inverter |
| CN113433839A (en) * | 2021-06-28 | 2021-09-24 | 杭州电子科技大学 | Synchronous rectification Boost converter simulation circuit based on virtual inductor and virtual capacitor |
| CN113824160A (en) * | 2021-09-18 | 2021-12-21 | 长沙理工大学 | Adaptive virtual inductor-based micro-grid parallel inverter power regulation method |
| CN114268114A (en) * | 2021-12-20 | 2022-04-01 | 安徽农业大学 | Secondary voltage compensation method for hybrid energy storage system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109904881A (en) | A kind of cascade microgrid power based on adaptive simulated capacitance divides equally control method | |
| CN104868500B (en) | Method for parallel operation control suitable to be used for microgrid inverter | |
| CN110676834B (en) | Isolated direct current micro-grid coordination method considering unmatched line resistance and local load | |
| CN108767869B (en) | Static reactive power compensator voltage adjusting method based on artificial neural network | |
| CN107147317B (en) | A kind of inverter parallel control method based on RC virtual impedance | |
| CN113541146B (en) | Power flow calculation optimization method of power system considering distributed power supply | |
| Cholamuthu et al. | A Grid‐Connected Solar PV/Wind Turbine Based Hybrid Energy System Using ANFIS Controller for Hybrid Series Active Power Filter to Improve the Power Quality | |
| CN111711198A (en) | FMS-based power distribution network feeder interconnection control method | |
| CN208142845U (en) | A kind of system for being inhibited to circulation of virtual synchronous machine when grid-connected | |
| Ganesh et al. | Development of simple technique for STATCOM for voltage regulation and power quality improvement | |
| CN116505534A (en) | Modeling method of direct type AC/AC type hybrid distribution transformer | |
| CN104917184B (en) | A kind of control system improving micro-capacitance sensor quality of voltage and control method | |
| CN108574276A (en) | A kind of direct-current grid power-sharing control method and system based on frequency injection | |
| CN111555358A (en) | Multi-distributed power supply parallel operation method based on self-adaptive droop control | |
| CN110518596A (en) | Distribution voltage Dynamic control method containing electric arc furnaces | |
| CN110266044A (en) | A kind of micro-grid connection control system and method based on energy accumulation current converter | |
| CN110429578A (en) | A kind of distributed DC grid control method | |
| Mohan et al. | Performance assessment of three-phase PV tied NPC multilevel inverter based UPQC | |
| Wang et al. | A unified droop control of AC microgrids under different line impedances: Revisiting droop control and virtual impedance method | |
| Rao et al. | DPFC performance with the comparison of PI and ANN controller | |
| Jiang et al. | A novel pre-synchronization control strategy for microgrid connections based on improved droop control | |
| CN115663780A (en) | Improved self-adaptive subsection droop control method for photovoltaic direct-current micro-grid | |
| CN115085193A (en) | Micro-grid demand side-oriented power spring regulation and control system and method | |
| Singh et al. | Analysis Modelling & Simulation of VSC based D-Statcom for Reactive VAR Compensation | |
| Jiang et al. | Intelligent Virtual Impedance Based Control to Enhance the Stability of Islanded Microgrid |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20190618 |