CN114123225B - Control method of three-phase reactive power compensator based on double prediction control - Google Patents
Control method of three-phase reactive power compensator based on double prediction control Download PDFInfo
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- 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
- H02J3/18—Arrangements for adjusting, eliminating or compensating reactive power in networks
- H02J3/1821—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators
- H02J3/1835—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators with stepless control
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- 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
- H02J3/18—Arrangements for adjusting, eliminating or compensating reactive power in networks
- H02J3/1821—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators
- H02J3/1835—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators with stepless control
- H02J3/1842—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators with stepless control wherein at least one reactive element is actively controlled by a bridge converter, e.g. active filters
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
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- 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]
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- 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
- Y02E40/30—Reactive power compensation
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Abstract
The invention relates to a control method of a three-phase reactive power compensator based on double prediction control, which comprises the following steps: (1) Sampling the current DC side voltage U dc Calculating the current required reference current I through a voltage prediction formula d_ref The method comprises the steps of carrying out a first treatment on the surface of the (2) Setting a required reactive current reference value I q_ref Carrying out coordinate transformation on the active reactive reference current to obtain a current reference value under an alpha beta coordinate system; simultaneously sampling three-phase grid current at the power grid side, substituting a current model predictive control calculation formula, bringing a cost function into the formula, and searching an optimal switching vector; (3) And (3) applying the optimal switching vector to the inverter to obtain a real current close to the reference current value, and completing the control process. The method can avoid the PI parameter setting process of double closed-loop control and can accelerate the overall dynamic response speed of the system.
Description
Technical Field
The invention belongs to the technical field of power electronics, and particularly relates to a control method of a three-phase reactive power compensator based on double prediction control.
Background
As the variety of loads on the grid becomes more and more, the active and reactive power produced by the devices that access the grid varies. Because reactive power existing in the power grid can influence the quality of electric energy in the power grid, when the reactive power is more, the power factor of the power grid is lower, and the waveform quality is poorer. The power grid thus has corresponding regulations on the power factor of the access device. In addition, when the power factor in the power grid is reduced, the reactive power compensator is also adopted to compensate or absorb the reactive power in the power grid, so that the reactive power in the power grid is ensured to be in a reasonable range.
The three-phase reactive compensator is basically identical to the power bidirectional flow three-phase rectifier from the perspective of the converter, but the purposes of the three-phase reactive compensator and the power bidirectional flow three-phase rectifier are different. Three-phase rectifiers typically draw power from a three-phase power grid, rectify three-phase ac power to dc power via corresponding control, and provide the dc power to a dc load. The reactive compensator is a three-phase rectifier working in a working mode of only sending or absorbing reactive power, and the direct-current end of the converter is only provided with a direct-current capacitor and is not connected with a load resistor. Theoretically, the reactive compensator does not consume active power at all and only operates in a pure reactive operating state. However, due to the internal resistance of the converter system, a small amount of active power needs to be absorbed from the power grid to maintain the stability of the dc side voltage, so that the reactive compensator can stably operate.
Currently, the most mature and widespread industrial application of three-phase reactive compensators is voltage-current double closed-loop PI control. Voltage-current double closed loop control is widely used in industry due to its stability. However, there are also a number of problems with dual closed loop PI control. For different reactive compensation systems, the voltage and current double closed loop parameters are different, and the parameter setting of the double closed loop control system is a complex process. In addition, the dynamic response speed of the voltage ring and the current ring is also limited by PI parameters, and the dynamic response speed cannot reach a very high speed.
Disclosure of Invention
The invention aims to provide a control method of a three-phase reactive power compensator based on double-prediction control, which not only can avoid the PI parameter setting process of double-closed-loop control, but also can accelerate the overall dynamic response speed of a system.
In order to achieve the above purpose, the invention adopts the following technical scheme: a three-phase reactive compensator based on double prediction control is used for controlling the three-phase reactive compensator according to the following steps:
(1) Sampling the current DC side voltage U dc Calculating the current required reference current I through a voltage prediction formula d_ref ；
(2) Setting a required reactive current reference value I q_ref Carrying out coordinate transformation on the active reactive reference current to obtain a current reference value under an alpha beta coordinate system; three-phase power grid for simultaneously sampling power grid sideSubstituting the current into a current model predictive control calculation formula, carrying a cost function, and searching an optimal switching vector;
(3) And (3) applying the optimal switching vector to the inverter to obtain a real current close to the reference current value, and completing the control process.
Further, the three-phase full-bridge three-phase converter is not only suitable for converters with three-level NPC topological structures, but also suitable for different three-phase topological structures, including three-phase full-bridge, five-level NNPC and seven-level CHB topological structures.
Further, a bi-predictive control including a voltage outer loop predictive control and a current inner loop predictive control is employed.
Further, the three-phase reactive compensator is a reactive power compensator with a three-phase three-level NPC topological structure and mainly comprises a three-phase three-level NPC converter, a direct-current side capacitor, a three-phase L-shaped filter, a three-phase power grid, a voltage outer loop predictive control and a current inner loop model predictive control; wherein the three-phase power grid voltage is U a 、U b 、U c The three-phase inductance current is I a 、I b 、I c The voltage of the direct current capacitor is U dc_upper And U dc_lower The method comprises the steps of carrying out a first treatment on the surface of the In order to realize the control of the reactive power compensator of the three-phase three-level NPC topological structure, the direct-current side capacitor voltage, the alternating-current side reactive power and the direct-current side capacitor balance are stably controlled to finish the control of the reactive power compensator;
in order to stably control the voltage of the capacitor at the direct current side, the voltage equation of the capacitor is shown as a formula (1), discretization is carried out on the capacitor, and a differential equation of the capacitor is solved as a formula (2);
reference voltage U of voltage ref Substituting the voltage U at the next time dc k+1 And the current capacitance voltage U dc k The difference is calculated by the formula (2) to obtain the direct current I required at the current moment dc And calculating the instantaneous power by the formula (3);
P dc ＝U dc *I dc (3)
the current of the alternating current side is calculated by converting the conservation of power into the alternating current grid side due to the principle of conservation of power; calculating the active current required by the power grid through the method (4), because of U q 0 in the rotating coordinate system, so I d ＝P active /U d The method comprises the steps of carrying out a first treatment on the surface of the After the active current of the system is stably controlled, the voltage is stabilized on a set reference value;
obtaining I after completing predictive calculation of voltage ring d_ref By a set reference reactive power Q ref Obtaining I by a reactive power calculation formula q_ref The method comprises the steps of carrying out a first treatment on the surface of the Converting the current component of the dq axis into a current component in an αβ coordinate system; converting the current of the dq coordinate system into a current in the αβ coordinate system as shown in formula (5);
in order to realize closed-loop control of current, an equation is established for the inductance; according to the KVL equation, a calculation formula shown in a formula (6) is obtained, and the voltage U of the power grid is known grid-αβ Thereafter, each voltage vector V s-αβ Uniquely corresponding to an output current; discretizing the current to obtain a current prediction calculation formula shown in a formula (7);
IL αβ k+1 ＝IL αβ k +(U grid-αβ -V s-αβ )*Ts/L (7)
performing iterative calculation according to the inductance current at the current moment and 27 voltage state vectors to obtain inductance current values of the 27 vectors at the next moment, comparing the inductance current values with a reference value, performing calculation by adopting a cost function shown in a formula (8), selecting a switching vector with the minimum cost function G, and applying the switching vector to the converter;
G＝|I α k+1 -I α_ref k+1 |+|I β k+1 -I β_ref k+1 | (8)
aiming at the problem of direct-current side capacitance balance of a topological structure of a three-level converter, a model is built for direct-current voltages of an upper capacitor and a lower capacitor; the capacitance voltage is shown as a formula (9);
performing difference on the upper capacitor voltage and the lower capacitor voltage to obtain a formula (10); according to equation (10), the capacitance voltage at the next time of the converter is related to the capacitance voltage difference at the present time and the neutral point current flowing at the present time, and the neutral point current I o And also with the switching state and the three-phase current I a 、I b 、I c Related to;
the capacitor voltage deviation of 27 vectors at the next moment is solved by combining the equation (10) and the equation (11), and weight distribution is carried out on the capacitor voltage deviation and the cost function value obtained by the equation (8), so that an equation of the equation (12) is obtained;
I o ＝I a *(1-|S a |)+I b *(1-|S b |)+I c *(1-|S c |) (11)
G＝|I α k+1 -I α_ref k+1 |+|I β k+1 -I β_ref k+1 |+λ*|ΔU dc k+1 | (12)
finding the optimal vector V best After the optimal voltage switching vector is determined, searching the corresponding output level in the voltage switching vector diagram, and generating a driving signal of the IGBT according to the switching state in the formula (13);
finally, the control of the three-phase reactive compensator based on the double-prediction control is completed.
Compared with the prior art, the invention has the following beneficial effects:
1. the current inner loop model predictive control is adopted, so that the traditional current inner loop parameter setting process can be avoided.
2. By adopting the voltage outer ring predictive control, the parameter setting process of the traditional voltage outer ring can be avoided.
3. Compared with the traditional double-closed-loop PI controlled three-phase reactive compensator, the three-phase reactive compensator adopting double-prediction control has faster dynamic response speed.
4. The three-phase reactive compensator adopting the double-prediction control does not need a PWM modulation module, and the control structure is simpler.
Drawings
FIG. 1 is a reactive compensator of a three level NPC topology in an embodiment of this invention;
FIG. 2 is a three-level space vector diagram in an embodiment of the invention;
FIG. 3 is a control block diagram of bi-predictive control in an embodiment of the invention;
FIG. 4 is a waveform of current dynamic response when reactive current changes in an embodiment of the present invention;
FIG. 5 is a waveform of the dynamic response of the voltage when the reactive current is changed in an embodiment of the present invention;
fig. 6 is a voltage dynamic response waveform when the dc voltage reference value is changed in the embodiment of the invention.
Detailed Description
The invention will be further described with reference to the accompanying drawings and examples.
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.
The embodiment provides a three-phase reactive power compensator based on double prediction control, which is controlled according to the following steps:
(1) Sampling the current DC side voltage U dc Calculating the current required reference current I through a voltage prediction formula d_ref ；
(2) Setting a required reactive current reference value I q_ref Carrying out coordinate transformation on the active reactive reference current to obtain a current reference value under an alpha beta coordinate system; simultaneously sampling three-phase grid current at the power grid side, substituting a current model predictive control calculation formula, bringing a cost function into the formula, and searching an optimal switching vector;
(3) And (3) applying the optimal switching vector to the inverter to obtain a real current close to the reference current value, and completing the control process.
The invention is not only suitable for converters with three-level NPC topological structures, but also can be popularized to different three-phase topological structures, such as three-phase full-bridge, five-level NNPC, seven-level CHB topological structures and the like, and has strong applicability.
The invention adopts the voltage outer loop predictive control and the current inner loop predictive control, avoids the parameter setting problem caused by the traditional PI control, and reduces the complexity of system design. Compared with the traditional PI control method, the double-prediction control method has a faster dynamic corresponding speed, and can enable the system to reach stability more quickly.
As shown in fig. 1, in this embodiment, the three-phase reactive power compensator is a reactive power compensator of a three-phase three-level NPC topology structure, and mainly comprises a three-phase three-level NPC converter, a dc side capacitor, a three-phase L-shaped filter, a three-phase power grid, a voltage outer loop prediction control and a current inner loop model prediction control; wherein the three-phase power grid voltage is U a 、U b 、U c The three-phase inductance current is I a 、I b 、I c The voltage of the direct current capacitor is U dc_upper And U dc_lower The method comprises the steps of carrying out a first treatment on the surface of the In order to realize the control of the reactive power compensator of the three-phase three-level NPC topological structure, the direct-current side capacitor voltage, the alternating-current side reactive power and the direct-current side capacitor balance are stably controlled so as to complete the control of the reactive power compensator. A control block diagram of the entire bi-predictive control is shown in fig. 3.
In order to stably control the voltage of the capacitor at the direct current side, the voltage equation of the capacitor is shown as a formula (1), discretization is carried out on the capacitor, and a differential equation of the capacitor is solved as a formula (2).
Reference voltage U of voltage ref Substituting the voltage U at the next time dc k+1 And the current capacitance voltage U dc k The difference is calculated by the formula (2) to obtain the direct current I required at the current moment dc And the calculation of the instantaneous power is performed by the formula (3).
P dc ＝U dc *I dc (3)
The current of the alternating current side is calculated by converting the conservation of power into the alternating current grid side due to the principle of conservation of power; calculating the active current required by the power grid through the method (4), because of U q 0 in the rotating coordinate system, soI d ＝P active /U d The method comprises the steps of carrying out a first treatment on the surface of the After the active current of the system is stably controlled, the voltage is stabilized on a set reference value.
Obtaining I after completing predictive calculation of voltage ring d_ref By a set reference reactive power Q ref Obtaining I by a reactive power calculation formula q_ref The method comprises the steps of carrying out a first treatment on the surface of the Converting the current component of the dq axis into a current component in an αβ coordinate system; as shown in equation (5), the current in the dq coordinate system is converted into the current in the αβ coordinate system.
In order to realize closed-loop control of current, an equation is established for the inductance; according to the KVL equation, a calculation formula shown in a formula (6) is obtained, and the voltage U of the power grid is known grid-αβ Thereafter, each voltage vector V s-αβ One output current can be uniquely corresponding; after discretizing the current, a current prediction calculation formula shown in formula (7) is obtained.
IL αβ k+1 ＝IL αβ k +(U grid-αβ -V s-αβ )*Ts/L (7)
And performing iterative calculation according to the inductance current at the current moment and 27 voltage state vectors to obtain inductance current values of the 27 vectors at the next moment, comparing the inductance current values with a reference value, performing calculation by adopting a cost function shown in a formula (8), selecting a switching vector with the minimum cost function G, and applying the switching vector to the converter.
G＝|I α k+1 -I α_ref k+1 |+|I β k+1 -I β_ref k+1 | (8)
Aiming at the problem of direct-current side capacitance balance of a topological structure of a three-level converter, a model is built for direct-current voltages of an upper capacitor and a lower capacitor; the capacitance voltage is shown in formula (9).
Performing difference on the upper capacitor voltage and the lower capacitor voltage to obtain a formula (10); according to equation (10), the capacitance voltage at the next time of the converter is related to the capacitance voltage difference at the present time and the neutral point current flowing at the present time, and the neutral point current I o And also with the switching state and the three-phase current I a 、I b 、I c Related to the following.
And (3) combining the equation (10) and the equation (11), solving the capacitor voltage deviation at the next moment of 27 vectors, and carrying out weight distribution with the cost function value obtained by the equation (8) to obtain the equation of the equation (12).
I o ＝I a *(1-|S a |)+I b *(1-|S b |)+I c *(1-|S c |) (11)
G＝|I α k+1 -I α_ref k+1 |+|I β k+1 -I β_ref k+1 |+λ*|ΔU dc k+1 | (12)
Finding the optimal vector V best After determining the optimal voltage switching vector, in the voltage switching vector diagram of fig. 2, the corresponding output level is found, and then the driving signal of the IGBT is generated according to the switching state in formula (13).
Finally, the control of the three-phase reactive compensator based on the double-prediction control is completed.
In order to realize the advantages of the invention, the three-phase reactive compensator with double predictive control and the voltage-current double closed-loop PI control are subjected to some performance comparison control.
From the perspective of a control strategy, the PI parameters of the voltage outer ring and the PI parameters of the current inner ring in the double-closed-loop PI control are required to be properly selected, so that a good dynamic response speed can be achieved. However, how to set the PI parameters is also a relatively complex process. The bi-predictive control adopted by the invention can complete the control of the whole process without setting PI parameters, and can realize faster dynamic response speed.
From the performance point of view of the reactive compensator, some simulation tests were performed on both methods. The voltage dynamic response speed when the direct current reference value is changed, and the current dynamic response speed and the voltage dynamic response speed when the reactive current reference value is changed are respectively tested. As shown in fig. 4 and 5, the current dynamic response speed and the dc voltage fluctuation when the reactive current changes. As can be seen from fig. 4, the current dynamic response waveform of the bi-predictive control is significantly faster than the speed of the dual closed loop PI control. Whereas the voltage anti-disturbance waveform in fig. 5 is more pronounced. The reactive compensator with double closed loop PI control has obvious voltage fluctuation and regulation process. And the reactive compensator with double predictive control is stable after only one voltage sag peak appears, and the response speed is completed within 0.01 s. The same is true in fig. 6, where the dynamic response speed of the bi-predictive control is also significantly faster than the bi-closed loop PI control when the voltage reference value is varied.
In summary, the bi-predictive control provided by the invention is superior to the dual closed-loop PI control from the angles of parameter setting and dynamic response speed.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the invention in any way, and any person skilled in the art may make modifications or alterations to the disclosed technical content to the equivalent embodiments. However, any simple modification, equivalent variation and variation of the above embodiments according to the technical substance of the present invention still fall within the protection scope of the technical solution of the present invention.
Claims (2)
1. The control method of the three-phase reactive power compensator based on the double-prediction control is characterized by comprising the following steps of:
(1) Sampling the current DC side voltage U dc Calculating the current required reference current I through a voltage prediction formula d_ref ；
(2) Setting a required reactive current reference value I q_ref Carrying out coordinate transformation on the active reactive reference current to obtain a current reference value under an alpha beta coordinate system; simultaneously sampling three-phase grid current at the power grid side, substituting a current model predictive control calculation formula, bringing a cost function into the formula, and searching an optimal switching vector;
(3) The optimal switching vector is acted on the inverter to obtain a real current which is close to a reference current value, and the control process is completed;
a double-prediction control comprising a voltage outer loop prediction control and a current inner loop prediction control is adopted;
the three-phase reactive power compensator is a reactive power compensator with a three-phase three-level NPC topological structure and mainly comprises a three-phase three-level NPC converter, a direct current side capacitor, a three-phase L-shaped filter, a three-phase power grid, voltage outer loop predictive control and current inner loop model predictive control; wherein the three-phase power grid voltage is U a 、U b 、U c The three-phase inductance current is I a 、I b 、I c The voltage of the direct current capacitor is U dc_upper And U dc_lower The method comprises the steps of carrying out a first treatment on the surface of the In order to realize the control of the reactive power compensator of the three-phase three-level NPC topological structure, the direct-current side capacitor voltage, the alternating-current side reactive power and the direct-current side capacitor balance are stably controlled to finish the control of the reactive power compensator;
in order to stably control the voltage of the capacitor at the direct current side, the voltage equation of the capacitor is shown as a formula (1), discretization is carried out on the capacitor, and a differential equation of the capacitor is solved as a formula (2);
reference voltage U of voltage ref Substituting the voltage U at the next time dc k+1 And the current capacitance voltage U dc k The difference is calculated by the formula (2) to obtain the direct current I required at the current moment dc And calculating the instantaneous power by the formula (3);
P dc ＝U dc *I dc (3)
the current of the alternating current side is calculated by converting the conservation of power into the alternating current grid side due to the principle of conservation of power; calculating the active current required by the power grid through the method (4), because of U q 0 in the rotating coordinate system, so I d ＝P active /U d The method comprises the steps of carrying out a first treatment on the surface of the After the active current of the system is stably controlled, the voltage is stabilized on a set reference value;
obtaining I after completing predictive calculation of voltage ring d_ref By a set reference reactive power Q ref Obtaining I by a reactive power calculation formula q_ref The method comprises the steps of carrying out a first treatment on the surface of the Converting the current component of the dq axis into a current component in an αβ coordinate system; converting the current of the dq coordinate system into a current in the αβ coordinate system as shown in formula (5);
in order to realize closed-loop control of current, an equation is established for the inductance; from the KVL equation, we findThe calculation formula shown in the formula (6) is that the voltage U of the power grid is known grid-αβ Thereafter, each voltage vector V s-αβ Uniquely corresponding to an output current; discretizing the current to obtain a current prediction calculation formula shown in a formula (7);
IL αβ k+1 ＝IL αβ k +(U grid-αβ -V s-αβ )*Ts/L(7)
performing iterative calculation according to the inductance current at the current moment and 27 voltage state vectors to obtain inductance current values of the 27 vectors at the next moment, comparing the inductance current values with a reference value, performing calculation by adopting a cost function shown in a formula (8), selecting a switching vector with the minimum cost function G, and applying the switching vector to the converter;
G＝|I α k+1 -I α_ref k+1 |+|I β k+1 -I β_ref k+1 |(8)
aiming at the problem of direct-current side capacitance balance of a topological structure of a three-level converter, a model is built for direct-current voltages of an upper capacitor and a lower capacitor; the capacitance voltage is shown as a formula (9);
performing difference on the upper capacitor voltage and the lower capacitor voltage to obtain a formula (10); according to equation (10), the capacitance voltage at the next time of the converter is related to the capacitance voltage difference at the present time and the neutral point current flowing at the present time, and the neutral point current I o And also with the switching state and the three-phase current I a 、I b 、I c Related to;
the capacitor voltage deviation of 27 vectors at the next moment can be solved by combining the equation (10) and the equation (11), and weight distribution is carried out on the capacitor voltage deviation and the cost function value obtained by the equation (8), so that an equation of the equation (12) is obtained;
I o ＝I a *(1-|S a |)+I b *(1-|S b |)+I c *(1-|S c |)(11)
G＝|I α k+1 -I α_ref k+1 |+|I β k+1 -I β_ref k+1 |+λ*|ΔU dc k+1 |(12)
finding the optimal vector V best After the optimal voltage switching vector is determined, searching the corresponding output level in the voltage switching vector diagram, and generating a driving signal of the IGBT according to the switching state in the formula (13);
finally, the control of the three-phase reactive compensator based on the double-prediction control is completed.
2. The control method of the three-phase reactive compensator based on the double predictive control according to claim 1 is applicable to not only converters of three-level NPC topologies, but also different three-phase topologies including three-phase full-bridge, five-level NNPC and seven-level CHB topologies.
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| CN101847874A (en) * | 2010-05-12 | 2010-09-29 | 华中科技大学 | Wattless current tracking method of static var compensator based on power balance |
| FR2983651A1 (en) * | 2011-12-06 | 2013-06-07 | Converteam Technology Ltd | REACTIVE ENERGY COMPENSATOR AND METHOD FOR REDUCING THE ASSOCIATED PAPILLOTE PHENOMENON. |
| FR2985616A1 (en) * | 2012-01-09 | 2013-07-12 | Converteam Technology Ltd | REACTIVE ENERGY COMPENSATOR AND METHOD OF BALANCING HALF BUS ASSOCIATED VOLTAGES |
| CN105375804A (en) * | 2015-12-17 | 2016-03-02 | 福州大学 | Model prediction current control method based on NPC topology grid connected inverter under asymmetric voltage |
| CN106549400A (en) * | 2016-12-10 | 2017-03-29 | 三峡大学 | A kind of control method of the distribution static synchronous compensator based on voltage prediction |
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| CN102916599B (en) * | 2012-10-26 | 2015-06-03 | 河南师范大学 | Model predication control method of three-phase PWM (pulse width modulation) rectifier under unbalanced voltage |
| CN107689724B (en) * | 2017-07-26 | 2021-02-19 | 华南理工大学 | Double-loop prediction control method based on dead beat control |
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| CN101847874A (en) * | 2010-05-12 | 2010-09-29 | 华中科技大学 | Wattless current tracking method of static var compensator based on power balance |
| FR2983651A1 (en) * | 2011-12-06 | 2013-06-07 | Converteam Technology Ltd | REACTIVE ENERGY COMPENSATOR AND METHOD FOR REDUCING THE ASSOCIATED PAPILLOTE PHENOMENON. |
| FR2985616A1 (en) * | 2012-01-09 | 2013-07-12 | Converteam Technology Ltd | REACTIVE ENERGY COMPENSATOR AND METHOD OF BALANCING HALF BUS ASSOCIATED VOLTAGES |
| CN105375804A (en) * | 2015-12-17 | 2016-03-02 | 福州大学 | Model prediction current control method based on NPC topology grid connected inverter under asymmetric voltage |
| CN106549400A (en) * | 2016-12-10 | 2017-03-29 | 三峡大学 | A kind of control method of the distribution static synchronous compensator based on voltage prediction |
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