CN112260290B - Grid-connected control method of voltage source type permanent magnet synchronous wind turbine generator under weak grid - Google Patents

Grid-connected control method of voltage source type permanent magnet synchronous wind turbine generator under weak grid Download PDF

Info

Publication number
CN112260290B
CN112260290B CN202011101150.3A CN202011101150A CN112260290B CN 112260290 B CN112260290 B CN 112260290B CN 202011101150 A CN202011101150 A CN 202011101150A CN 112260290 B CN112260290 B CN 112260290B
Authority
CN
China
Prior art keywords
grid
voltage
side converter
moment
current
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
Application number
CN202011101150.3A
Other languages
Chinese (zh)
Other versions
CN112260290A (en
Inventor
谢震
张悬光
高翔
张兴
王超
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hefei University of Technology
Original Assignee
Hefei University of Technology
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hefei University of Technology filed Critical Hefei University of Technology
Priority to CN202011101150.3A priority Critical patent/CN112260290B/en
Publication of CN112260290A publication Critical patent/CN112260290A/en
Application granted granted Critical
Publication of CN112260290B publication Critical patent/CN112260290B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
    • 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
    • H02J3/01—Arrangements for reducing harmonics or ripples
    • 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
    • H02J3/381—Dispersed generators
    • 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
    • H02J2203/00—Indexing scheme relating to details of circuit arrangements for AC mains or AC distribution networks
    • H02J2203/20—Simulating, e g planning, reliability check, modelling or computer assisted design [CAD]
    • 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
    • H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
    • H02J2300/20—The dispersed energy generation being of renewable origin
    • H02J2300/28—The renewable source being wind energy
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/70—Wind energy
    • Y02E10/76—Power conversion electric or electronic aspects
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/40—Arrangements for reducing harmonics

Abstract

The invention discloses a grid-connected control method of a voltage source type permanent magnet synchronous wind turbine generator under a weak grid, and relates to the field of wind power generation. According to the grid-connected control method, the grid-connected control of the wind turbine generator is realized by implementing model prediction control based on the virtual synchronous generator on the grid-side converter. Direct control is carried out on direct voltage by adopting a direct voltage ring on the basis of the control of a conventional virtual synchronous generator; on the basis of a conventional capacitor voltage inner ring, a current inner ring with finite set model predictive control is adopted, and the current is taken as an optimization target, so that the effective control of the capacitor voltage and the filter inductance current is realized. The wind turbine generator structure related to the control method can run at low switching frequency, reduces loss and has good dynamic performance. Meanwhile, the system can have great inertia, voltage and frequency supporting capacity under the condition of weak power grid, and the stability of the system is improved by stable control of direct-current voltage.

Description

Grid-connected control method of voltage source type permanent magnet synchronous wind turbine generator under weak grid
Technical Field
The invention relates to the field of wind power generation, and particularly provides a grid-connected control method of a voltage source type permanent magnet synchronous wind turbine generator under a weak grid.
Background
Wind energy is an indispensable part in the field of new energy power generation as a clean new energy, and as the demand of wind power generation in China increases, a large-capacity and high-proportion wind power system is continuously incorporated into a power grid, so that the stability of the power grid frequency is influenced. The generator of the wind turbine generator has inertia, but the control structure of grid-connected on the power grid side enables the output power of the wind turbine generator to be decoupled from the power grid frequency, and corresponding compensation power is difficult to be generated when the frequency fluctuates so as to maintain the stability of the system frequency; on the other hand, under the condition of weak power grid, the fluctuation of the grid side frequency and voltage can cause the instability of the direct current side voltage, so that the whole system has power oscillation and instability.
The grid-connected converter based on the grid voltage vector directional control strategy generally realizes synchronization with a power grid through a phase-locked loop (PLL), but the stability problem brought by the PLL cannot be ignored, particularly, under the weak power grid condition with a low short-circuit ratio (SCR), the grid-connected converter realized through the PLL is difficult to realize a good control effect, and improper parameter design even can cause system instability.
The permanent magnet synchronous wind driven generator is connected with a power grid through a back-to-back converter, and electric energy generated by the generator is transmitted to the power grid through the back-to-back converter. The back-to-back converter consists of a machine side converter, a network side converter and a direct current bus capacitor. Such a converter with a capacitor on the dc side is also referred to as a voltage source converter. The voltage source type converter is widely applied to the field of new energy as a grid-connected interface, synchronization with a power grid is generally achieved through a phase-locked loop (PLL), but under the condition of weak power grid, the dynamic performance of the PLL is seriously deteriorated, and even the converter is unstable. The invention provides a virtual synchronizer control method applied to improvement of a grid-side converter of a permanent magnet synchronous wind turbine generator.
In order to solve the problem that a wind turbine generator cannot participate in frequency adjustment, a machine side converter of a permanent magnet synchronous wind turbine generator in an existing control strategy usually adopts a virtual inertia control method, the method is similar to a thermal power generator rotor motion equation, the frequency of a grid-connected point is detected through a phase-locked loop (PLL), the frequency is processed and added to the power set of the machine side, compensation power is provided for a power grid by releasing rotor kinetic energy of the wind turbine generator, and the grid side converter also usually adopts a virtual synchronous machine control method for providing certain frequency and voltage supporting capacity. However, with further increase of the wind power ratio and disturbance under the weak grid condition, the conventional control of the grid-side converter cannot meet the condition of frequency adjustment, and does not have the capability of stabilizing the direct-current voltage in the process of frequency adjustment, and cannot achieve a good supporting effect of the frequency voltage under the weak grid condition, so that a method needs to be adopted to coordinate and optimize the system inertia and the direct-current voltage stability.
In recent years, the virtual synchronization idea realized by the speed regulation of the synchronous machine and the characteristic simulation of the exciter can meet corresponding requirements, but how to realize the virtual synchronization control and the related analysis in the wind power is related, but is still insufficient. The method comprises the following steps of document 'congratulation of family, Song Mei Yan, Lanzhou, Huang Lin, Xinghui and Wang Shao'. A permanent magnet direct-drive wind turbine generator virtual inertia coordination control strategy applicable to a weak power grid [ J ]. power system automation, 2018, 42 (09): 83-90' provide a permanent magnet direct-drive wind turbine generator virtual inertia coordination control strategy suitable for a weak power grid, the control strategy can provide virtual inertia for the power grid by utilizing the rotation kinetic energy stored in a fan, and the grid-connected self-synchronization of a direct-drive wind turbine generator grid-side inverter is dynamically realized by utilizing a direct current capacitor. The fan rotor dynamic energy compensation method is essentially characterized in that the kinetic energy contained in the fan rotor is utilized to make up the frequency response capability of the fan, the fan has certain inertia response capability, the kinetic energy in the fan rotor is limited, when the system disturbance is large, the rotor kinetic energy cannot provide enough active support, meanwhile, the direct-current voltage control structure parameters are more, and the adjustment difficulty is large.
At present, a virtual synchronous control strategy for stabilizing the voltage on the direct current side mainly only relates to research on an inverter, but the virtual synchronous control strategy is less applied to research on a wind turbine generator, and a part of control methods of the inverter cannot be directly applied to a grid-connected converter of a direct-drive wind turbine generator due to a back-to-back grid-connected structure of the wind turbine generator.
The finite set model predictive control is concerned and researched by a plurality of scholars due to the advantages of simple algorithm, superior dynamic performance, multi-target constraint and the like, and is applied to the control algorithm of the wind generating set. Document "zhusha, luyaoguang, wangzihao, yeweiqing" permanent magnet synchronous motor torque prediction virtual voltage vector control [ J ] electric transmission, 2019, 49 (06): 24-29 "propose the virtual voltage vector control method of torque prediction, restrain the torque ripple through predicting the torque, increase the system stability. However, the current research on the model predictive control of the wind generating set is not combined with the virtual synchronous control, and the frequency and inertia supporting capability is lacked under a weak grid.
In summary, the existing virtual synchronization control technology has the following problems:
1. under the condition of a weak power grid, the performance of the phase-locked loop is seriously deteriorated, so that the stability of the system is influenced;
2. the limitation of active-frequency virtual synchronization is adopted, which means that the network side receives a power instruction to control active output and needs the machine side to control direct-current voltage, and the machine side control is possibly unstable;
3. the traditional virtual synchronous generator control usually comprises voltage and current double-loop control, and more parameters need to be adjusted and set.
Disclosure of Invention
The invention aims to optimize the power grid frequency and the stable operation of the wind generation set under the condition of high power and high proportion wind generation based on the conventional virtual synchronous control, improve the grid-connected stability of the wind generation set under the weak grid and inhibit the voltage fluctuation of the direct current side caused by disturbance. Specifically, the wind turbine, the permanent magnet synchronous generator, the machine side converter for implementing conventional virtual inertia control and the grid side converter for implementing virtual synchronization-based finite set model predictive control are adopted to form the wind turbine generator, and the grid-connected optimization control of the wind turbine generator under the weak grid condition is realized by implementing virtual synchronization and model predictive control on the grid side converter.
Objects of the inventionThe invention provides a grid-connected control method of a voltage source type permanent magnet synchronous wind turbine generator under a weak grid, wherein the permanent magnet synchronous wind turbine generator applying the control method comprises a wind turbine, a permanent magnet synchronous generator, a machine side converter, a grid side converter, a direct current capacitor C, a filter, a line inductor and a power grid, wherein the filter comprises a filter inductor and a filter capacitor; the wind turbine, the permanent magnet synchronous generator, the machine side converter, the grid side converter, the filter inductor, the line inductor and the power grid are sequentially connected; one end of the filter capacitor is connected between the filter inductor and the line inductor, and the other end of the filter capacitor is grounded; a direct current capacitor C is connected in parallel between a direct current positive bus P and a direct current negative bus N between the machine-side converter and the grid-side converter; the network side converter consists of a, b and c three-phase bridge arms, each phase of bridge arm comprises 2 switching tubes, namely the network side converter comprises 6 switching tubes which are respectively marked as switching tube S a1 And a switch tube S a2 Switch tube S b1 And a switch tube S b2 Switch tube S c1 Switch tube S c2 ；
The grid-connected control method realizes the grid-connected control of the permanent magnet synchronous wind turbine generator by implementing the model prediction control based on the virtual synchronous generator on the grid-side converter, and comprises the following specific steps:
step 1, setting the current moment as k, and performing signal acquisition and coordinate transformation:
sampling k moment filter inductance current i La (k)，i Lb (k)，i Lc (k) And coordinate transformation is carried out to obtain a component i of a dq axis of the filter inductance current at the k moment under a synchronous rotation dq coordinate system Ld (k)，i Lq (k) (ii) a Sampling k moment grid-connected point voltage U sa (k)，U sb (k)，U sc (k) And coordinate transformation is carried out to obtain a component U of a dq axis of the voltage of the grid-connected point at the k moment under a synchronous rotation dq coordinate system sd (k)，U sq (k) (ii) a Sampling k moment grid-connected point current i sa (k)，i sb (k)，i sc (k) And coordinate transformation is carried out to obtain the grid-connected point current dq axis quantity i at the k moment under the synchronous rotation dq coordinate system sd (k)，i sq (k) (ii) a Sampling the voltage at two sides of the DC capacitor and recording as DC voltage U dc ；
Step 2, the grid-connected point voltage dq axis component U at the k moment obtained in the step 1 sd (k)，U sq (k) And a dot-on point current dq axis component i at the time of k sd (k)，i sq (k) Substituting into a power calculation equation to calculate to obtain the active power P of the grid-connected point at the moment k e (k) Reactive power Q of grid-connected point at time k e (k) The expression of the power calculation equation is as follows:
Figure BDA0002722214130000041
step 3, calculating the phase angle of the virtual power grid at the moment k
Figure BDA0002722214130000042
Step 3.1, the direct current voltage U obtained in the step 1 is processed dc Substituting the power reference value into a calculation equation to obtain a power reference value P ref The expression of the power reference value calculation equation is as follows:
Figure BDA0002722214130000043
in the formula (I), the compound is shown in the specification,
Figure BDA0002722214130000044
is a reference value of DC voltage, K p Is the proportionality coefficient of the DC voltage loop, K i The integral coefficient of the direct current voltage loop is shown, and S is a Laplace operator;
step 3.2, the active power P of the point of connection at the K moment obtained in the step 2 e (k) With the power reference P obtained in step 3.1 ref Substituting the obtained value into a virtual synchronous machine simulation speed regulator equation to obtain the k-time simulation power grid angular frequency omega * (k) The virtual synchronizer simulates an expression of a speed regulator equation as follows:
Figure BDA0002722214130000051
in the formula, ω 0 The method comprises the following steps that A, a rated value of the angular frequency of the power grid is obtained, D is a damping coefficient, J is an inertia coefficient, omega (k) is the virtual angular frequency of the power grid at the moment k, and delta omega is a frequency difference;
step 3.3, simulating the power grid angular frequency omega at the k moment obtained in the step 3.2 * (k) Integral operation is carried out to obtain a phase angle of the virtual power grid at the moment k
Figure BDA0002722214130000054
Step 4, obtaining the reactive power Q of the point of connection at the moment k in the step 2 e (k) Substituting into a reactive voltage equation to obtain a voltage reference value U ref The expression of the reactive voltage equation is as follows:
U ref ＝E 0 +n×{Q ref -Q e (k)}
in the formula, E 0 For the given value of the terminal voltage of the virtual synchronous generator, n is the droop coefficient of reactive power regulation, Q ref A given value of reactive power is obtained;
step 5, combining the grid connection point voltage dq axis component U at the k moment obtained in the step 1 sd (k)，U sq (k) Substituting the current reference value calculation equation to calculate and obtain the dq axis component of the filtering inductance current reference value at the k moment
Figure BDA0002722214130000052
The expression of the current reference value calculation equation is as follows:
Figure BDA0002722214130000053
in the formula, K pu Is the proportionality coefficient of the voltage loop PI, K iu Is the integral coefficient of the voltage loop PI, C f Is the capacitance value of the filter;
step 6, setting a switching state signal of the grid-side converter;
obtaining switching state signals of k-moment three-phase bridge arms of the grid-side converter according to the driving signals of the grid-side converter, and recording the switching state signals as k-momentSwitch state signal S of a-phase bridge arm of grid-carving side converter a And k moment switching state signal S of b-phase bridge arm of grid-side converter b Switching state signal S of c-phase bridge arm of grid-side converter at moment k c (ii) a Switch state signal S a 、S b 、S c Equal to 0 or 1;
obtaining voltage vectors u acting at 8 k moments according to the switching states of three-phase bridge arms of the grid-side converter j (S a ，S b ，S c ) J is 0, 1 …, 7, as follows:
if S is a ＝0，S b ＝0，S c When k is 0, the voltage vector acting at time k is denoted as u 0 (000)；
If S is a ＝0，S b ＝0，S c When 1, the voltage vector acting at time k is denoted as u 1 (001)；
If S is a ＝0，S b ＝1，S c When k is 0, the voltage vector acting at time k is denoted as u 2 (010)；
If S is a ＝0，S b ＝1，S c When 1, the voltage vector acting at time k is denoted as u 3 (011)；
If S is a ＝1，S b ＝0，S c When k is 0, the voltage vector acting at time k is denoted as u 4 (100)；
If S is a ＝1，S b ＝0，S c When 1, the voltage vector acting at time k is denoted as u 5 (101)；
If S is a ＝1，S b ＝1，S c When k is 0, the voltage vector acting at time k is denoted as u 6 (110)；
If S is a ＝1，S b ＝1，S c When 1, the voltage vector acting at time k is denoted as u 7 (111)；
The set of voltage vectors acting at the above 8 k moments is denoted as a set U, and the expression is as follows:
U＝{u 0 (000)，u 1 (001)，u 2 (010)，u 3 (011)，u 4 (100)，u 5 (101)，u 6 (110)，u 7 (111)}；
step 7, calculating d-axis component U of bridge arm output voltage of grid-side converter at moment k ind (k) Q-axis component U of bridge arm output voltage of grid-side converter at moment K inq (k) The calculation formula is as follows:
Figure BDA0002722214130000061
step 8, calculating through an inductance current prediction equation to obtain a d-axis component i of the filter inductance prediction current at the moment k +1 d Filter inductance prediction current q-axis component i at (k +1) and k +1 moments q (k +1), the expression of the inductor current prediction equation is as follows:
Figure BDA0002722214130000062
in the formula, T s To sample time, R f Is parasitic resistance of filter inductor, L f Is the filter inductance value;
step 9, substituting the switch state signal corresponding to each voltage vector in the set U obtained in the step 6 into the step 7 to obtain d-axis components U of output voltages of bridge arms of the grid-side converter at 8 k moments ind (k) And 8 k moment grid-side converter bridge arm output voltage q-axis components U inq (k) (ii) a D-axis component U of bridge-arm side output voltage of 8 k-time grid-side converter ind (k) And 8 q-axis components U of bridge-arm-side output voltage of grid-side converter at k moments inq (k) Substituting the step 8 to obtain the d-axis component i of the filter inductor prediction current at 8 k +1 moments d (k +1) and 8 k +1 time instants of filter inductor prediction current q-axis component i q (k+1)；
Step 10, setting an error function, and performing rolling optimization to calculate the error function corresponding to each voltage vector in the set U;
step 10.1, defining an error function as err, wherein the expression is as follows:
Figure BDA0002722214130000071
step 10.2, filter inductance predicted current d-axis component i at 8 k +1 moments obtained in step 9 d (k +1) and 8 k +1 time instants of filter inductor prediction current q-axis component i q (k +1) is substituted into the expression of the error function err in the step 10.1 to calculate, and 8 error function values are obtained;
step 11 of selecting the error function value having the smallest value among the 8 error function values obtained in step 10, recording the corresponding error function as a target error function, recording a voltage vector corresponding to the target error function as an optimum voltage vector, and recording a switching state signal S corresponding to the optimum voltage vector as an optimum voltage vector a 、S b 、S c As a control signal for the grid-side converter at time k.
Preferably, the switching state signal S of a-phase bridge arm of the grid-side converter at the time k in step 7 a And k moment switching state signal S of b-phase bridge arm of grid-side converter b Switching state signal S of c-phase bridge arm of grid-side converter at moment k c The specific states of (a) are as follows:
S a 1 denotes a-phase bridge arm switching tube S of the grid-side converter a1 Conducting, switching tube S a2 Turning off;
S a 0 represents a-phase bridge arm switching tube S of the grid-side converter a1 Turn off and switch tube S a2 Conducting;
S b 1 denotes a b-phase bridge arm switching tube S of the grid-side converter b1 Conducting, switching tube S b2 Turning off;
S b 0 represents the switching tube S of the b-phase bridge arm of the grid-side converter b1 Turn-off, switch tube S b2 Conducting;
S c 1 denotes a c-phase arm switching tube S of the grid-side converter c1 Conducting, switching tube S c2 Turning off;
S c 0 represents the c-phase bridge arm switching tube S of the network-side converter c1 Turn-off, switch tube S c2 And conducting.
Compared with the prior art, the invention has the beneficial effects that:
1. compared with the conventional virtual synchronous generator control of a wind driven generator, the control method increases the control of the direct current side capacitor voltage, increases the capacity of stabilizing the direct current voltage while providing the grid-connected voltage and the frequency supporting capacity for the system, ensures that the power transmission is more stable due to the stability of the direct current side voltage, and improves the stability of the system under a weak grid.
2. Compared with the traditional grid-side converter control, the grid-side converter control method has the advantages that the phase-locked loop is omitted, the self-synchronization of the power grid can be carried out under the condition that the phase-locked loop is not used, and the instability of the system caused by the deterioration of the phase-locked loop under the weak grid condition is avoided.
3. The method provided by the invention considers that the traditional current inner ring is replaced by the limited set model prediction current inner ring, the optimal switching vector is obtained through model prediction control, the traditional capacitance voltage inner ring and the limited set model prediction current inner ring are combined, the switching signal is generated by using a model prediction method, the system can be operated under low switching frequency, the switching loss of the grid-side converter is reduced, the power transmission efficiency is increased, and meanwhile, the regulation of the proportional integral parameter of the traditional current ring is removed.
Drawings
FIG. 1 is a topological diagram of a wind turbine generator in an embodiment of the present invention;
FIG. 2 is a topology diagram of a grid-side converter in an embodiment of the present invention;
fig. 3 is a control block diagram of a grid-side converter in an embodiment of the present invention;
FIG. 4 is a control block diagram of a virtual synchronous control portion including a DC voltage loop according to an embodiment of the present invention;
FIG. 5 is a diagram illustrating simulation of DC voltage variation during frequency fluctuation under a low short-circuit ratio in an embodiment of the present invention;
FIG. 6 is a diagram illustrating active power variation simulation according to an embodiment of the present invention;
FIG. 7 is a simulation diagram of frequency variation according to an embodiment of the present invention.
Detailed Description
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
Fig. 1 is a topological diagram of a permanent magnet synchronous wind turbine generator according to an embodiment of the present invention. In fig. 1, PMSG is a permanent magnet synchronous motor, C is a dc capacitor, L is a filter inductor, C1 is a filter capacitor, Lx is a line inductor, a is a grid-connected point, P is a dc positive bus, and N is a dc negative bus. As shown in fig. 1, the permanent magnet synchronous wind turbine generator set to which the optimization control method is applied includes a wind turbine, a permanent magnet synchronous generator, a machine side converter, a grid side converter, a direct current capacitor C, a filter, a line inductor and a power grid, where the filter includes a filter inductor and a filter capacitor; the wind turbine, the permanent magnet synchronous generator, the machine side converter, the grid side converter, the filter inductor, the line inductor and the power grid are sequentially connected; one end of the filter capacitor is connected between the filter inductor and the line inductor, and the other end of the filter capacitor is grounded; and the direct current capacitor C is connected in parallel between a direct current positive bus P and a direct current negative bus N between the machine-side converter and the grid-side converter.
Fig. 2 is a topology diagram of a grid-side converter in the embodiment of the present invention. As can be seen from fig. 2, the grid-side converter is composed of three-phase bridge arms a, b, and c, each phase of bridge arm includes 2 switching tubes, that is, the grid-side converter includes 6 switching tubes, which are respectively marked as switching tube S a1 And a switch tube S a2 Switch tube S b1 Switch tube S b2 And a switch tube S c1 Switch tube S c2 . The collector of each switch tube is defined as positive end, the emitter is defined as negative end, for a-phase bridge arm, the switch tube S a1 The positive end of the switch tube is connected with a direct current positive bus P and a switch tube S a1 Is connected with the switch tube S a2 Positive terminal of (1), switch tube S a2 The negative end of the direct current negative bus is connected with a direct current negative bus N; for the b-phase bridge arm, switching tube S b1 The positive end of the switch tube is connected with a direct current positive bus P and a switch tube S b1 Is connected with a switch tube S b2 Positive terminal of (2), switch tube S b2 The negative end of the positive electrode is connected with a direct current negative bus N; for c-phase bridge arm, switching tube S c1 The positive end of the switch tube is connected with a direct current positive bus P and a switch tube S c1 Is connected with a switch tube S c2 Positive terminal of (2), switch tube S c2 The negative end of the direct current negative bus is connected with a direct current negative bus N;
fig. 3 is a control block diagram of the grid-side converter in the embodiment of the present invention. Fig. 4 is a control block diagram of a part of the control block diagram of fig. 3, that is, a control block diagram of a virtual synchronization control portion including a dc voltage loop. As can be seen from fig. 3 and 4, the grid-connected control method of the present invention implements model predictive control based on the virtual synchronous generator on the grid-side converter, thereby implementing grid-connected control of the permanent magnet synchronous wind turbine, and includes the following specific steps:
and step 1, setting the current time as k, and performing signal acquisition and coordinate transformation.
(1) Sampling k moment filter inductance current i La (k)，i Lb (k)，i Lc (k) And coordinate transformation is carried out to obtain a component i of a filter inductance current dq axis at the k moment under a synchronous rotation dq coordinate system Ld (k)，i Lq (k) In that respect The coordinate transformation formula is as follows:
Figure BDA0002722214130000101
wherein (k-1) is a time immediately before the current time,
Figure BDA0002722214130000102
and (k-1) the virtual power grid phase angle.
(2) Sampling k moment grid-connected point voltage U sa (k)，U sb (k)，U sc (k) And coordinate transformation is carried out to obtain a component U of a grid-connected point voltage dq axis at the k moment under a synchronous rotation dq coordinate system sb (k)，U sq (k) .1. the The coordinate transformation formula is as follows:
Figure BDA0002722214130000103
(3) sampling k moment grid-connected point current i sa (k)，i sb (k)，i sc (k) And coordinate transformation is carried out to obtain the grid-connected point current dq axis quantity i at the k moment under the synchronous rotation dq coordinate system sd (k)，i sq (k) In that respect The coordinate transformation formula is as follows:
Figure BDA0002722214130000104
(4) sampling the voltage at two sides of the DC capacitor and recording as DC voltage U dc 。
Step 2, combining the grid connection point voltage dq axis component U at the k moment obtained in the step 1 sd (k)，U sq (k) And the grid-connected point current dq axis component i at the moment k sd (k)，i sq (k) Substituting into a power calculation equation to calculate to obtain the active power P of the grid-connected point at the moment k e (k) And k moment point of connection reactive power Q e (k) The expression of the power calculation equation is as follows:
Figure BDA0002722214130000105
step 3, calculating the phase angle of the virtual power grid at the moment k
Figure BDA0002722214130000111
Step 3.1, the direct current voltage U obtained in the step 1 is used dc Substituting the power reference value into a calculation equation to obtain a power reference value P ref The expression of the power reference value calculation equation is as follows:
Figure BDA0002722214130000112
in the formula (I), the compound is shown in the specification,
Figure BDA0002722214130000113
is a DC voltage reference value, K p Is the proportionality coefficient of the DC voltage loop, K i And S is a Laplace operator. Step 3.1 corresponds to the dc voltage outer loop control in fig. 4. In this embodiment, K p ＝20，K i ＝150。
Step 3.2, the active power P of the point of connection at the K moment obtained in the step 2 e (k) With the power reference value P obtained in step 3.1 ref Substituting the obtained value into a virtual synchronous machine simulation speed regulator equation to obtain the k-time simulation power grid angular frequency omega * (k) The virtual synchronizer simulates an expression of a governor equation as follows:
Figure BDA0002722214130000114
in the formula, ω 0 And D is a rated value of the angular frequency of the power grid, D is a damping coefficient, J is an inertia coefficient, omega (k) is the angular frequency of the virtual power grid at the moment k, and delta omega is a frequency difference. Step 3.2 corresponds to the active power loop control in fig. 4, which is a conventional active frequency loop. In this embodiment, D is 600, ω 0 ＝100π，J＝2。
Step 3.3, simulating the power grid angular frequency omega at the k moment obtained in the step 3.2 * (k) Integral operation is carried out to obtain a phase angle of the virtual power grid at the moment k
Figure BDA0002722214130000115
Step 4, obtaining the reactive power Q of the point of connection at the moment k in the step 2 e (k) Substituting into reactive voltage equation to obtain voltage reference value U ref The reactive voltage equation has the following expression:
U ref ＝E 0 +n×{Q ref -Q e (k)}
in the formula, E 0 Setting a virtual synchronous generator terminal voltage value, n is a reactive power regulation droop coefficient, Q ref The given value of reactive power. Step 4 corresponds to the reactive voltage loop control in fig. 4. In this embodiment, E 0 ＝563.3826V，n＝0.0002，Q ref ＝0。
Step 5, combining the grid connection point voltage dq axis component U at the k moment obtained in the step 1 sd (k)，U sq (k) Substituting the current reference value into a calculation equation of the current reference value to calculate and obtain a dq axis component of the filter inductance current reference value at the k moment
Figure BDA0002722214130000121
The expression of the current reference value calculation equation is as follows:
Figure BDA0002722214130000122
in the formula, K pu Is the proportionality coefficient of the voltage loop PI, K iu Is the integral coefficient of the voltage loop PI, C f Is the capacitance value of the filter. In this example K pu ＝10，K pi ＝50，C f ＝330μf。
Step 6, setting a switch state signal of the grid-side converter;
obtaining switching state signals of k-time three-phase bridge arms of the grid-side converter according to the driving signals of the grid-side converter, and recording the switching state signals as switching state signals S of a-phase bridge arms of the grid-side converter at the k-time a And k moment switching state signal S of b-phase bridge arm of grid-side converter b And K time switching state signal S of c-phase bridge arm of grid-side converter c (ii) a Switch state signal S a 、S b 、S c Equal to 0 or 1;
obtaining voltage vectors u acting at 8 k moments according to the switching states of three-phase bridge arms of the grid-side converter j (S a ，S b ，S c ) J is 0, 1 …, 7, as follows:
if S is a ＝0，S b ＝0，S c When k is 0, the voltage vector acting at time k is denoted as u 0 (000)；
If S is a ＝0，S b ＝0，S c When 1, the voltage vector acting at time k is denoted as u 1 (001)；
If S is a ＝0，S b ＝1，S c When equal to 0, the voltage vector acting at time k is denoted as u 2 (010)；
If S is a ＝0，S b ＝1，S c When 1, the voltage vector acting at time k is denoted as u 3 (011)；
If S is a ＝1，S b ＝0，S c When equal to 0, the voltage vector acting at time k is denoted as u 4 (100)；
If S is a ＝1，S b ＝0，S c When 1, the voltage vector acting at time k is denoted as u 5 (101)；
If S is a ＝1，S b ＝1，S c When k is 0, the voltage vector acting at time k is denoted as u 6 (110)；
If S is a ＝1，S b ＝1，S c When 1, the voltage vector acting at time k is denoted as u 7 (111)；
The set of the voltage vectors acting at the above 8 k moments is recorded as a set U, and the expression is as follows:
U＝{u 0 (000)，u 1 (001)，u 2 (010)，u 3 (011)，u 4 (100)，u 5 (101)，u 6 (110)，u 7 (111)}。
switching state signal S of a-phase bridge arm of k-time grid-side converter a Switching state signal S of b-phase bridge arm of grid-side converter at moment k b Switching state signal S of c-phase bridge arm of grid-side converter at moment k c The specific states of (c) are as follows:
S a 1 represents a switching tube S of an a-phase bridge arm of the grid-side converter a1 Conducting and switching tube S a2 Turning off;
S a 0 represents a-phase bridge arm switching tube S of the grid-side converter a1 Turn-off, switch tube S a2 Conducting;
S b 1 represents a switching tube S of a b-phase bridge arm of the grid-side converter b1 Conducting, switching tube S b2 Turning off;
S b 0 represents the switching tube S of the b-phase bridge arm of the network-side converter b1 Turn-off, switch tube S b2 Conducting;
S c 1 denotes a c-phase arm switching tube S of the grid-side converter c1 Conducting, switching tube S c2 Turning off;
S c 0 represents the c-phase bridge arm switching tube S of the network-side converter c1 Turn-off, switch tube S c2 And conducting.
Step 7, calculating the network side change at the k momentD-axis component U of output voltage of bridge arm of current transformer ind (k) Q-axis component U of bridge arm output voltage of grid-side converter at moment K inq (k) The calculation formula is as follows:
Figure BDA0002722214130000131
step 8, calculating and obtaining d-axis component i of filter inductor prediction current at the moment k +1 through an inductor current prediction equation d Predicted current q-axis component i of filter inductor at time (k +1) and k +1 q (k +1), the expression of the inductor current prediction equation is as follows:
Figure BDA0002722214130000132
in the formula, T s To sample time, R f Is parasitic resistance of filter inductor, L f Is the filter inductance value. In this embodiment, T s ＝0.1ms，R f ＝0.003Ω，L f ＝4mH。
Step 9, substituting the switch state signal corresponding to each voltage vector in the set U obtained in the step 6 into the step 7 to obtain d-axis components U of output voltages of bridge arms of the grid-side converter at 8 k moments ind (k) And 8 q-axis components U of output voltage of bridge arm of grid-side converter at k moments inq (k) (ii) a D-axis component U of bridge-arm side output voltage of 8 k-time grid-side converter ind (k) And 8 k moment grid-side converter bridge arm side output voltage q-axis component U inq (k) Substituting the step 8 to obtain the d-axis component i of the filter inductor prediction current at 8 k +1 moments d (k +1) and 8 k +1 time instants of filter inductor prediction current q-axis component i q (k+1)。
And step 10, setting an error function, and performing rolling optimization to calculate the error function corresponding to each voltage vector in the set U.
Step 10.1, defining an error function as err, wherein the expression is as follows:
Figure BDA0002722214130000141
step 10.2, filter inductance predicted current d-axis component i at 8 k +1 moments obtained in step 9 d (k +1) and 8 k +1 time instants of filter inductor prediction current q-axis component i q (k +1) is substituted into the expression of the error function err in the step 10.1 to calculate, and 8 error function values are obtained;
step 11, selecting the error function value with the smallest value from the 8 error function values obtained in step 10, and recording the corresponding error function as a target error function, and recording the voltage vector corresponding to the target error function as an optimal voltage vector, and the switching state signal S corresponding to the optimal voltage vector a 、S b 、S c As a control signal for the grid-side converter at time k.
In order to verify the effectiveness of the invention, the invention is subjected to simulation verification. Simulation parameters: rated power P of wind turbine generator N 2MW, rated voltage U N 690V stator resistance R s 0.0078 Ω, d-axis inductance L d 1.42mH, q-axis inductance L q 2.75mH, permanent magnet flux linkage psi f 12.5791Wb, number of pole pairs p n 30, sample period T s ＝0.1ms。
FIG. 5 is a diagram illustrating simulation of DC voltage variation during frequency fluctuation under a low short-circuit ratio in an embodiment of the present invention; FIG. 6 is a simulation diagram of active power variation in an embodiment of the present invention; FIG. 7 is a simulation diagram of frequency variation according to an embodiment of the present invention.
In the simulation of fig. 5, the system starts sending power ramp commands at 5s, resulting in dc voltage ripple regulation due to power imbalance of the system. When the power climbing reaches the maximum value in 6.5s, the direct-current voltage begins to drop and tends to be stable; the grid frequency drops to 49.9Hz within 7.5s-9s, while the fluctuations in the dc voltage are small. It can be seen from fig. 5 that, under the condition of low short-circuit ratio of weak power grid, the fluctuation of the dc voltage can be well inhibited when the power starts to change, and when the grid frequency decreases, the dc voltage decreases less and can be stabilized at the steady state value, and when the frequency recovers, the dc voltage can be recovered and stabilized at the command valueThe control strategy also has a good effect of stabilizing the direct-current voltage under the weak network, particularly at a low short-circuit ratio. In the simulation diagram of fig. 6, P _ PMSG is the active power of the machine side, P _ VSG is the active power of the network side, the power command is increased in a ramp manner within 2s-3s, the active power of the machine side and the active power of the network side can both finally reach a steady state along with the change of the power command value, and the difference value between the machine side power and the network side power is the power loss after the power loss is reduced. In the simulation of fig. 7, the grid frequency drops to 49.99Hz at 5s, from which it can be seen that after the grid frequency drops, the virtual grid frequency f meas The drop is gentle, and the drop is only slightly overshot, so that the frequency of a power grid can be kept up to the end; likewise, when the grid frequency is restored within 6.5s, the virtual grid frequency f meas The method can smoothly keep up with the power grid frequency under the condition of small overshoot, and can well inhibit frequency disturbance and enhance the system stability.
In conclusion, the novel virtual synchronous control strategy provided by the invention can well operate under the weak network, and can inhibit the influence of voltage and frequency disturbance under the weak network on the stability of the system, so that the system has good frequency supporting capability and direct-current voltage stabilizing capability, meanwhile, the inertia and the damping of the system are increased, and the influence of power oscillation on the system is effectively improved. A novel voltage source type virtual synchronous control strategy is verified to have the capability of stabilizing direct-current voltage and the capability of suppressing frequency disturbance under a weak network.

Claims (2)

1. A grid-connected control method of a voltage source type permanent magnet synchronous wind turbine generator under a weak grid is disclosed, the permanent magnet synchronous wind turbine generator applying the control method comprises a wind turbine, a permanent magnet synchronous generator, a machine side converter, a grid side converter, a direct current capacitor C, a filter, a line inductor and a power grid, wherein the filter comprises a filter inductor and a filter capacitor; the wind turbine, the permanent magnet synchronous generator, the machine side converter, the grid side converter, the filter inductor, the line inductor and the power grid are sequentially connected; one end of the filter capacitor is connected between the filter inductor and the line inductor, and the other end of the filter capacitor is grounded; with DC capacitor C connected in parallel between machine-side and network-side convertersA direct current positive bus P and a direct current negative bus N; the network side converter consists of a, b and c three-phase bridge arms, each phase of bridge arm comprises 2 switching tubes, namely the network side converter comprises 6 switching tubes which are respectively marked as switching tube S a1 Switch tube S a2 And a switch tube S b1 Switch tube S b2 Switch tube S c1 Switch tube S c2 ；
The grid-connected control method is characterized in that the grid-connected control of the permanent magnet synchronous wind turbine generator is realized by implementing model prediction control based on a virtual synchronous generator on a grid-side converter, and the method specifically comprises the following steps:
step 1, setting the current moment as k, and performing signal acquisition and coordinate transformation:
sampling k moment filter inductance current i La (k)，i Lb (k)，i Lc (k) And coordinate transformation is carried out to obtain a component i of a filter inductance current dq axis at the k moment under a synchronous rotation dq coordinate system Ld (k)，i Lq (k) (ii) a Sampling k moment grid-connected point voltage U sa (k)，U sb (k)，U sc (k) And coordinate transformation is carried out to obtain a component U of a dq axis of the voltage of the grid-connected point at the k moment under a synchronous rotation dq coordinate system sd (k)，U sq (k) (ii) a Sampling k moment grid-connected point current i sa (k)，i sb (k)，i sc (k) And coordinate transformation is carried out to obtain the current dq axis quantity i of the grid-connected point at the k moment under the synchronous rotation dq coordinate system sd (k)，i sq (k) (ii) a Sampling the voltage at two sides of the DC capacitor and recording as DC voltage U dc ；
Step 2, combining the grid connection point voltage dq axis component U at the k moment obtained in the step 1 sd (k)，U sq (k) And the grid-connected point current dq axis component i at the moment k sd (k)，i sq (k) Substituting into a power calculation equation to calculate to obtain the active power P of the grid-connected point at the moment k e (k) Reactive power Q of grid-connected point at time k e (k) The expression of the power calculation equation is as follows:
Figure FDA0002722214120000021
step 3, calculating the phase angle of the virtual power grid at the moment k
Figure FDA0002722214120000026
Step 3.1, the direct current voltage U obtained in the step 1 is used dc Substituting the power reference value into a calculation equation to obtain a power reference value P ref The expression of the power reference value calculation equation is as follows:
Figure FDA0002722214120000022
in the formula (I), the compound is shown in the specification,
Figure FDA0002722214120000023
is a reference value of DC voltage, K p Is the proportionality coefficient of the DC voltage loop, K i The integral coefficient of the direct current voltage loop is shown, and S is a Laplace operator;
step 3.2, the active power P of the point of connection at the K moment obtained in the step 2 e (k) With the power reference P obtained in step 3.1 ref Substituting the angular frequency omega into a virtual synchronous machine simulation speed regulator equation to obtain the k moment simulation power grid angular frequency omega * (k) The virtual synchronizer simulates an expression of a speed regulator equation as follows:
Figure FDA0002722214120000024
in the formula, ω 0 The method comprises the following steps that A, a rated value of the angular frequency of a power grid, D, J, omega (k), a frequency difference, delta omega and a frequency difference are included, wherein D is a damping coefficient, J is an inertia coefficient, omega (k) is the angular frequency of the virtual power grid at the moment k;
step 3.3, simulating the power grid angular frequency omega at the k moment obtained in the step 3.2 * (k) Integrating to obtain a phase angle of the virtual power grid at the moment k
Figure FDA0002722214120000025
In the step 4, the step of,the reactive power Q of the point of connection at the moment k obtained in the step 2 is obtained e (k) Substituting into a reactive voltage equation to obtain a voltage reference value U ref The expression of the reactive voltage equation is as follows:
U ref ＝E 0 +n×{Q ref -Q e (k)}
in the formula, E 0 Setting a virtual synchronous generator terminal voltage value, n is a reactive power regulation droop coefficient, Q ref A given reactive power value;
step 5, the grid-connected point voltage dq axis component U at the k moment obtained in the step 1 sd (k)，U sq (k) Substituting the current reference value calculation equation to calculate and obtain the dq axis component of the filtering inductance current reference value at the k moment
Figure FDA0002722214120000031
The expression of the current reference value calculation equation is as follows:
Figure FDA0002722214120000032
in the formula, K pu Is the proportionality coefficient of the voltage loop PI, K iu Is the integral coefficient of the voltage loop PI, C f Is the capacitance value of the filter;
step 6, setting a switching state signal of the grid-side converter;
obtaining switching state signals of k-time three-phase bridge arms of the grid-side converter according to the driving signals of the grid-side converter, and recording the switching state signals as switching state signals S of a-phase bridge arms of the grid-side converter at the k-time a Switching state signal S of b-phase bridge arm of grid-side converter at moment k b And K time switching state signal S of c-phase bridge arm of grid-side converter c (ii) a Switch state signal S a 、S b 、S c Equal to 0 or 1;
obtaining voltage vectors u acting at 8 k moments according to the switching states of three-phase bridge arms of the grid-side converter j (S a ，S b ，S c ) J ═ 0, 1., 7, specifically as follows:
if S is a ＝0，S b ＝0，S c When equal to 0, the voltage vector acting at time k is denoted as u 0 (000)；
If S is a ＝o，S b ＝0，S c When 1, the voltage vector acting at time k is denoted as u 1 (001)；
If S is a ＝0，S b ＝1，S c When k is 0, the voltage vector acting at time k is denoted as u 2 (010)；
If S is a ＝o，S b ＝1，S c When 1, the voltage vector acting at time k is denoted as u 3 (011)；
If S is a ＝1，S b ＝0，S c When k is 0, the voltage vector acting at time k is denoted as u 4 (100)；
If S is a ＝1，S b ＝0，S c When 1, the voltage vector acting at time k is denoted as u 5 (101)；
If S is a ＝1，S b ＝1，S c When equal to 0, the voltage vector acting at time k is denoted as u 6 (110)；
If S is a ＝1，S b ＝1，S c When 1, the voltage vector acting at time k is denoted as u 7 (111)；
The set of the voltage vectors acting at the above 8 k moments is recorded as a set U, and the expression is as follows:
U＝{u 0 (000)，u 1 (001)，u 2 (010)，u 3 (011)，u 4 (100)，u 5 (101)，u 6 (110)，u 7 (111)}；
step 7, calculating d-axis component U of bridge arm output voltage of grid-side converter at moment k ind (k) Q-axis component U of bridge arm output voltage of grid-side converter at moment K inq (k) The calculation formula is as follows:
Figure FDA0002722214120000041
step 8, through an inductive current prediction equation meterD-axis component i of filter inductor prediction current at k +1 moment is obtained through calculation d Filter inductance prediction current q-axis component i at (k +1) and k +1 moments q (k +1), the expression of the inductor current prediction equation is as follows:
Figure FDA0002722214120000042
in the formula, T s To sample time, R f Is parasitic resistance of filter inductor, L f Is the filter inductance value;
step 9, substituting the switch state signal corresponding to each voltage vector in the set U obtained in the step 6 into the step 7 to obtain d-axis components U of output voltages of bridge arms of the grid-side converter at 8 k moments ind (k) And 8 k moment grid-side converter bridge arm output voltage q-axis components U inq (k) (ii) a D-axis component U of bridge-arm side output voltage of 8 k-time grid-side converter ind (k) And 8 k moment grid-side converter bridge arm side output voltage q-axis component U inq (k) Substituting the step 8 to obtain the d-axis component i of the filter inductor prediction current at 8 k +1 moments d (k +1) and 8 k +1 time instants of filter inductor prediction current q-axis component i q (k+1)；
Step 10, setting an error function, and performing rolling optimization to calculate the error function corresponding to each voltage vector in the set U;
step 10.1, defining an error function as err, wherein the expression is as follows:
Figure FDA0002722214120000043
step 10.2, filter inductance predicted current d-axis component i at 8 k +1 moments obtained in step 9 d (k +1) and 8 k +1 time instants of filter inductor prediction current q-axis component i q (k +1) is substituted into the expression of the error function err in the step 10.1 for calculation to obtain 8 error function values;
step 11, selecting the error function value with the minimum value from the 8 error function values obtained in step 10 and recording the corresponding error function as the error functionA target error function, recording the voltage vector corresponding to the target error function as an optimal voltage vector, and generating a switch state signal S corresponding to the optimal voltage vector a 、S b 、S c As a control signal for the grid-side converter at time k.
2. The grid-connected control method of the voltage source type permanent magnet synchronous wind turbine generator under the weak grid as claimed in claim 1, wherein step 7 is performed by using a switching state signal S of a phase bridge arm of the grid-side converter at the time k a Switching state signal S of b-phase bridge arm of grid-side converter at moment k b Switching state signal S of c-phase bridge arm of grid-side converter at moment k c The specific states of (a) are as follows:
S a 1 denotes a-phase bridge arm switching tube S of the grid-side converter a1 Conducting, switching tube S a2 Turning off;
S a 0 represents a-phase bridge arm switching tube S of the grid-side converter a1 Turn-off, switch tube S a2 Conducting;
S b 1 denotes a b-phase bridge arm switching tube S of the grid-side converter b1 Conducting, switching tube S b2 Turning off;
S b 0 represents the switching tube S of the b-phase bridge arm of the grid-side converter b1 Turn-off, switch tube S b2 Conducting;
S c 1 denotes a c-phase arm switching tube S of the grid-side converter c1 Conducting, switching tube S c2 Turning off;
S c 0 represents the c-phase bridge arm switching tube S of the network-side converter c1 Turn-off, switch tube S c2 And conducting.
CN202011101150.3A 2020-10-13 2020-10-13 Grid-connected control method of voltage source type permanent magnet synchronous wind turbine generator under weak grid Active CN112260290B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011101150.3A CN112260290B (en) 2020-10-13 2020-10-13 Grid-connected control method of voltage source type permanent magnet synchronous wind turbine generator under weak grid

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011101150.3A CN112260290B (en) 2020-10-13 2020-10-13 Grid-connected control method of voltage source type permanent magnet synchronous wind turbine generator under weak grid

Publications (2)

Publication Number Publication Date
CN112260290A CN112260290A (en) 2021-01-22
CN112260290B true CN112260290B (en) 2022-09-13

Family

ID=74243320

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011101150.3A Active CN112260290B (en) 2020-10-13 2020-10-13 Grid-connected control method of voltage source type permanent magnet synchronous wind turbine generator under weak grid

Country Status (1)

Country Link
CN (1) CN112260290B (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112994111B (en) * 2021-04-26 2022-02-22 浙江大学 Permanent magnet synchronous fan access weak power grid stability analysis method considering power control
DE102021119328B3 (en) 2021-07-26 2022-10-20 Rolls-Royce Solutions GmbH Method of operating a generator set, device for operating a generator set and generator set
CN116264391A (en) * 2021-12-15 2023-06-16 新疆金风科技股份有限公司 Control method and control device of voltage source type wind generating set
CN115566698B (en) * 2022-11-30 2023-03-28 国网山西省电力公司电力科学研究院 Droop inverter rapid frequency control method based on disturbance following method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107681915A (en) * 2017-10-17 2018-02-09 南京理工大学 Based on the multi-electrical level inverter combination method and device for determining frequency finite aggregate model prediction
CN108683198A (en) * 2018-03-29 2018-10-19 合肥工业大学 The voltage-controlled type virtual synchronous method of double-fed wind power generator group
CN109217363A (en) * 2018-08-28 2019-01-15 南京理工大学 A kind of virtual synchronous generator control method based on model current prediction
CN110460106A (en) * 2019-08-08 2019-11-15 国网电力科学研究院有限公司 DFIG virtual synchronous control method and system under a kind of unbalanced power grid
CN110739721A (en) * 2019-09-27 2020-01-31 中国电力科学研究院有限公司 voltage source type wind turbine generator set control method and system

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9568901B2 (en) * 2012-08-27 2017-02-14 Nec Corporation Multi-objective energy management methods for micro-grids

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107681915A (en) * 2017-10-17 2018-02-09 南京理工大学 Based on the multi-electrical level inverter combination method and device for determining frequency finite aggregate model prediction
CN108683198A (en) * 2018-03-29 2018-10-19 合肥工业大学 The voltage-controlled type virtual synchronous method of double-fed wind power generator group
CN109217363A (en) * 2018-08-28 2019-01-15 南京理工大学 A kind of virtual synchronous generator control method based on model current prediction
CN110460106A (en) * 2019-08-08 2019-11-15 国网电力科学研究院有限公司 DFIG virtual synchronous control method and system under a kind of unbalanced power grid
CN110739721A (en) * 2019-09-27 2020-01-31 中国电力科学研究院有限公司 voltage source type wind turbine generator set control method and system

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
High Voltage Ride-Through of Grid-side Converter for PMSG Based Directly Driven Wind Turbines;LIU Changxian et al.;《 2016 35th Chinese Control Conference (CCC)》;20160829;第8528-8532页 *
Robust Predictive Control of Grid-Side Power Converters for PMSG Wind Turbine Systems with Stability Analysis;Yongdu Wang et al.;《2020 IEEE International Conference on Industrial Technology (ICIT)》;20200416;第763-768页 *
两电机转矩同步系统有限集模型预测控制;魏玉春等;《电工技术学报》;20161031;第31卷(第19期);第115-122页 *
适应于弱电网的永磁直驱风电机组虚拟惯量协调控制策略;贺家发等;《电力系统自动化》;20180510;第42卷(第9期);第83-90页 *

Also Published As

Publication number Publication date
CN112260290A (en) 2021-01-22

Similar Documents

Publication Publication Date Title
CN112260290B (en) Grid-connected control method of voltage source type permanent magnet synchronous wind turbine generator under weak grid
CN110071531B (en) Large-scale energy storage and permanent magnet wind power generation coordinated control system and method
CN111277001A (en) Fan grid-connected control method based on virtual synchronous generator parameter adaptive control
CN112019113B (en) Wind turbine generator optimization control method based on multi-objective model prediction
CN110611331B (en) Method for supporting grid frequency by grid-connected power electronic equipment
CN113346559B (en) Low-voltage ride-through power switching control method for direct-drive wind power system under extremely weak grid
CN111509773B (en) Voltage source type wind turbine generator fault ride-through control method suitable for weak power grid
CN113098365B (en) Method and system for suppressing network side current harmonic of motor driving system without electrolytic capacitor
CN109560733B (en) Voltage source type control method for DFIG machine side converter
CN111342491A (en) Grid-connected control method and system suitable for flywheel energy storage device
CN110513846B (en) Control method for air conditioner compressor without electrolytic capacitor
CN115882762A (en) Frequency optimization control method of grid-connected wind power system
CN111049178A (en) Method for analyzing stability control of direct-drive permanent magnet wind turbine generator through VSC-HVDC grid connection
CN113346562B (en) Control method for low-voltage ride through of permanent magnet direct-drive wind turbine generator
CN109039180B (en) Fractional order control method for grid connection process of doubly-fed induction generator
CN112968471B (en) Active support control method for new energy power generation equipment on power grid frequency
CN115347618B (en) Grid-connected power conversion device for micro-grid and application method thereof
CN114865711B (en) Dual-mode switching control method and system for new energy grid-connected inverter
CN116488211A (en) VSG improved parameter self-adaption method for single-phase photovoltaic energy storage
CN114243787B (en) Control method and system for improving transient synchronization stability of wind power grid-connected system
Zhao et al. Maximal power point tracking under speed-mode control for wind energy generation system with doubly fed introduction generator
CN113794211B (en) Voltage source type double-fed wind turbine generator active power oscillation-based suppression method
CN113937789B (en) Voltage source type double-fed fan feedforward damping control method based on fractional order filtering
CN115021317A (en) Low voltage ride through control method for new energy self-synchronizing grid-connected inverter
CN114678900A (en) Self-synchronization grid connection method of network construction type double-fed wind turbine generator based on flux linkage control

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