CN113067336A - Three-level active filter based on model predictive control - Google Patents
Three-level active filter based on model predictive control Download PDFInfo
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- CN113067336A CN113067336A CN202110541495.9A CN202110541495A CN113067336A CN 113067336 A CN113067336 A CN 113067336A CN 202110541495 A CN202110541495 A CN 202110541495A CN 113067336 A CN113067336 A CN 113067336A
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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
- H02J3/01—Arrangements for reducing harmonics or ripples
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- 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
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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
- Y02E40/20—Active power filtering [APF]
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Abstract
The invention discloses a three-level active filter based on model predictive control, and relates to the technical field of active filtering; the method comprises the following steps: a main circuit topological structure of a three-level active filter; (II) designing a three-level active filter system scheme; (III) detecting harmonic waves and reactive power of the three-level active filter; (IV) model prediction control strategy; the method adopts Matlab/Simulink simulation software to carry out system simulation modeling, and verifies that the proposed three-level active filter system based on model predictive control has good harmonic compensation effect through simulation research; a three-level APF system experiment platform with DSPF28335 as a core is built, communication between the system and an upper computer is achieved, the upper computer displays operation parameters of the three-level APF system, real-time control over the system by the upper computer is achieved, and compensation of the three-level active power filter system for harmonic waves based on model prediction control is achieved finally.
Description
Technical Field
The invention belongs to the technical field of active filtering, and particularly relates to a three-level active filter based on model predictive control.
Background
With the rapid development of science and technology, more and more power electronic devices are largely applied to electric equipment such as extra-high voltage alternating current and direct current transmission, new energy, distributed power supplies and the like, so that the power grid and a load structure are greatly changed, the nonlinear distortion of voltage and current on the power supply side of the power grid is caused, and the harmonic pollution of a power system is caused. The harmonic wave can increase the loss of the equipment, overheat the equipment, reduce the efficiency and the utilization rate of the equipment and also influence the reliability of the relay protection device. Therefore, harmonic suppression has become an increasingly important issue. For harmonic treatment, two basic ideas exist: one is to modify the power electronic device itself so that it does not generate harmonics and the power factor can be controlled to 1, which is certainly only applicable to power electronic devices as a main harmonic source; the other one is that a harmonic compensation device is arranged to compensate harmonic waves, and the compensation device can compensate various harmonic sources. An Active Power Filter (APF) is a novel Power electronic device that can compensate for harmonic waves and improve Power quality, and has attracted extensive attention by virtue of the advantages of mature topology and flexible control strategy.
Currently, the commonly used two-level APF has many problems, such as: small number of output levels, low compensation efficiency, high switching loss, etc. Compared with a two-level APF, the three-level APF can make up for the existing problems, greatly improves the capacity of the system, and has better compensation effect and higher system reliability. Therefore, when the harmonic waves are treated by using the three-level APF, the method has very important practical significance on how to realize efficient and stable control on the three-level APF.
Disclosure of Invention
The problem of how to realize efficient and stable control on the three-level APF when the three-level APF is used for controlling harmonics in the prior art is solved; the invention aims to provide a three-level active filter based on model predictive control.
The invention discloses a model predictive control-based three-level active filter, which comprises the following steps:
(I) a main circuit topological structure of the three-level active filter:
each phase of the diode clamping structure consists of four power switching devices, and meanwhile, each phase is also connected with two clamping diodes;
and (II) designing a three-level active filter system scheme:
by analyzing the load current, active, reactive and harmonic components are separated by applying a harmonic detection algorithm; simultaneously, detecting an APF output current signal in real time, sending the reactive power and harmonic components and the APF output current signal into a current tracking control unit, generating 12 paths of PWM signals through a system main control unit, controlling each power switch tube of a main circuit by using a driving circuit, and generating compensation current opposite to load side harmonic and reactive current, thereby realizing reactive power and harmonic compensation of output current of the three-level converter and finally obtaining an expected current waveform with the same frequency and phase as the voltage of a power grid;
and (III) detecting harmonic waves and reactive power of the three-level active filter:
i p -i qthe method comprises the steps of subtracting fundamental wave current from three-phase current signals to obtain three-phase harmonic current components, and further completing detection work of the harmonic current;
(IV) model prediction control strategy:
when the model prediction is applied to an APF system, firstly, a reference current prediction value is calculated according to the sampling values of the grid voltage and the compensating current, then, rolling optimization is carried out on 27 switching states, and the compensating current prediction value, a direct-current side voltage deviation prediction value and the switching times are required to be calculated for each rollingF SW And calculating and comparing the value function G, and finally selecting the switch state which enables the value function to be minimum to output.
Compared with the prior art, the invention has the beneficial effects that:
firstly, Matlab/Simulink simulation software is used for system simulation modeling, and simulation research verifies that the proposed three-level active filter system based on model predictive control has a good harmonic compensation effect.
And secondly, building a three-level APF system experiment platform with DSPF28335 as a core, realizing communication between the system and an upper computer, displaying the operating parameters of the three-level APF system by the upper computer, realizing real-time control of the system by using the upper computer, and finally realizing the compensation of the three-level active power filter system based on model predictive control on harmonic waves.
Drawings
For ease of illustration, the invention is described in detail by the following detailed description and the accompanying drawings.
FIG. 1 is a topology diagram of a diode-clamped three-level converter according to the present invention;
FIG. 2 is a schematic structural view of the present invention;
FIG. 3 shows the present inventioni p -i q A detection mode schematic diagram;
FIG. 4 is a diagram of a model predictive control architecture in accordance with the present invention.
Detailed Description
In order that the objects, aspects and advantages of the invention will become more apparent, the invention will be described by way of example only, and in connection with the accompanying drawings. It is to be understood that such description is merely illustrative and not intended to limit the scope of the present invention. The structure, proportion, size and the like shown in the drawings are only used for matching with the content disclosed in the specification, so that the person skilled in the art can understand and read the description, and the description is not used for limiting the limit condition of the implementation of the invention, so the method has no technical essence, and any structural modification, proportion relation change or size adjustment still falls within the range covered by the technical content disclosed by the invention without affecting the effect and the achievable purpose of the invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.
It should be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and/or processing steps closely related to the scheme according to the present invention are shown in the drawings, and other details not so relevant to the present invention are omitted.
The specific implementation mode adopts the following technical scheme:
(1) three-level active filter main circuit topological structure:
in the three-level topology, a diode clamping structure is used, each phase of the three-level topology is composed of four power switches, and two clamping diodes are connected to each phase of the three-level topology, and the topology structure of the three-level topology is shown in fig. 1.
(2) The scheme design of the three-level active filter system comprises the following steps:
the overall design of the three-level active filter system is shown in fig. 2.
As can be seen from fig. 2, the three-level active filter works: by analyzing the load current, active and reactive power and harmonic components are separated by applying a harmonic detection algorithm. And simultaneously detecting an APF output current signal in real time, sending the reactive and harmonic components and the APF output current signal into a current tracking control unit, generating 12 paths of PWM signals through a system main control unit, controlling each power switch tube of a main circuit by using a driving circuit, and generating compensation current opposite to load side harmonic and reactive current, thereby realizing reactive and harmonic compensation of the output current of the three-level converter and finally obtaining an expected current waveform with the same frequency and phase as the voltage of a power grid.
(3) The detection technology of harmonic waves and reactive power of the three-level active filter comprises the following steps:
p-qthe detection method is an earlier harmonic detection method, but the method can generate compensation errors when the power grid is asymmetric or distorted, and the theory is improved to providei p -i qThe method is a detection method.
i p -i qThe method comprises subtracting fundamental current from three-phase current signal to obtain three-phase harmonic current component, and detecting harmonic current,i p-i qFIG. 3 shows a schematic diagram of a detection method, wherein when harmonic and reactive of a system need to be detected simultaneously, a break-off diagram is showni qPath, pairi qAnd performing inverse transformation to obtain the reactive current of the system.
(4) Model predictive control strategy:
the model prediction is essentially on-line optimal control, and has the advantages of high dynamic response speed, low requirement on the precision of the model, convenient modeling and the like. The process description can be obtained by simple experiments, and a non-minimized description model is adopted, so that the system has better robustness and stability; by adopting a rolling optimization strategy instead of global primary optimization, uncertainty caused by factors such as model mismatch, distortion and interference can be timely made up, and the dynamic performance is good; the algorithm is easy to popularize to actual processes with constraints, large delay, non-minimum phase, nonlinearity and the like, and particularly, the method can effectively process multivariable and constrained problems, has the advantages that a prediction interval of a strategy researched by the text can take multiple optimization control targets into consideration, and the like, and is widely applied to a nonlinear control system.
The model predictive control mainly comprises a prediction model, rolling optimization and feedback correction, and the model predictive control structure is shown in fig. 4. When the model prediction is applied to an APF system, firstly, a reference current prediction value is calculated according to sampling values of power grid voltage, compensation current and the like, then rolling optimization is carried out on 27 switch states, and the compensation current prediction value, a direct-current side voltage deviation prediction value and the switch conversion times are calculated for each rollingF SW And calculating and comparing the value function G, and finally selecting the switch state which enables the value function to be minimum to output.
The effect of the embodiment is as follows:
(1) by introducing the integral structure of the three-level APF system, a current harmonic detection technology is introduced, a plurality of current harmonic detection methods are analyzed and compared, and finally an instantaneous reactive power theory-based method is selectedi p -i q And (3) harmonic detection method. Meanwhile, the current tracking control strategy is analyzed, a current tracking algorithm based on model predictive control is provided, and compared with the traditional control algorithm, the control strategy is more convenient and simpler and has better effect.
(2) Matlab/Simulink simulation software is used for system simulation modeling, and simulation research verifies that the proposed three-level active filter system based on model predictive control has a good harmonic compensation effect.
(3) A three-level APF system experiment platform with DSPF28335 as a core is built, communication between the system and an upper computer is achieved, the upper computer displays operation parameters of the three-level APF system, real-time control over the system by the upper computer is achieved, and compensation of the three-level active power filter system for harmonic waves based on model prediction control is achieved finally.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (1)
1. A model predictive control-based three-level active filter, comprising: the method comprises the following steps:
(I) a main circuit topological structure of the three-level active filter:
each phase of the diode clamping structure consists of four power switching devices, and meanwhile, each phase is also connected with two clamping diodes;
and (II) designing a three-level active filter system scheme:
by analyzing the load current, active, reactive and harmonic components are separated by applying a harmonic detection algorithm; simultaneously, detecting an APF output current signal in real time, sending the reactive power and harmonic components and the APF output current signal into a current tracking control unit, generating 12 paths of PWM signals through a system main control unit, controlling each power switch tube of a main circuit by using a driving circuit, and generating compensation current opposite to load side harmonic and reactive current, thereby realizing reactive power and harmonic compensation of output current of the three-level converter and finally obtaining an expected current waveform with the same frequency and phase as the voltage of a power grid;
and (III) detecting harmonic waves and reactive power of the three-level active filter:
i p -i qthe method comprises the steps of subtracting fundamental wave current from three-phase current signals to obtain three-phase harmonic current components, and further completing detection work of the harmonic current;
(IV) model prediction control strategy:
when the model prediction is applied to an APF system, firstly, a reference current prediction value is calculated according to the sampling values of the grid voltage and the compensating current, then, rolling optimization is carried out on 27 switching states, and the compensating current prediction value, a direct-current side voltage deviation prediction value and the switching times are required to be calculated for each rollingF SW And calculating and comparing the value function G, and finally selecting the switch state which enables the value function to be minimum to output.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101976968A (en) * | 2010-09-25 | 2011-02-16 | 西安交通大学 | Method for controlling midpoint potential of direct-current bus of three-level inverter |
| CN105140923A (en) * | 2015-09-15 | 2015-12-09 | 深圳市海思瑞科电气技术有限公司 | Active filtering method and filter |
| CN105790271A (en) * | 2016-04-12 | 2016-07-20 | 国网江苏省电力公司扬州供电公司 | Active power electric filter circuit based on three-phase bridge inversion circuit and work method thereof |
| CN107069732A (en) * | 2017-04-18 | 2017-08-18 | 西南交通大学 | The active filter harmonic current compensation method predicted based on minimum current error model |
| CN108599165A (en) * | 2018-05-16 | 2018-09-28 | 哈尔滨理工大学 | Three level active filters, its application system and method based on Compound Control Strategy |
| CN109085765A (en) * | 2018-08-06 | 2018-12-25 | 江苏师范大学 | Three level active power filter rapid model prediction control method of neutral-point-clamped formula |
| CN111106606A (en) * | 2019-12-20 | 2020-05-05 | 中铁电气化局集团有限公司 | Harmonic current compensation method and device, active filter and storage medium |
| CN112448697A (en) * | 2020-10-30 | 2021-03-05 | 合肥工业大学 | Active filter optimization method and system based on quantum particle swarm optimization |
-
2021
- 2021-05-18 CN CN202110541495.9A patent/CN113067336A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101976968A (en) * | 2010-09-25 | 2011-02-16 | 西安交通大学 | Method for controlling midpoint potential of direct-current bus of three-level inverter |
| CN105140923A (en) * | 2015-09-15 | 2015-12-09 | 深圳市海思瑞科电气技术有限公司 | Active filtering method and filter |
| CN105790271A (en) * | 2016-04-12 | 2016-07-20 | 国网江苏省电力公司扬州供电公司 | Active power electric filter circuit based on three-phase bridge inversion circuit and work method thereof |
| CN107069732A (en) * | 2017-04-18 | 2017-08-18 | 西南交通大学 | The active filter harmonic current compensation method predicted based on minimum current error model |
| CN108599165A (en) * | 2018-05-16 | 2018-09-28 | 哈尔滨理工大学 | Three level active filters, its application system and method based on Compound Control Strategy |
| CN109085765A (en) * | 2018-08-06 | 2018-12-25 | 江苏师范大学 | Three level active power filter rapid model prediction control method of neutral-point-clamped formula |
| CN111106606A (en) * | 2019-12-20 | 2020-05-05 | 中铁电气化局集团有限公司 | Harmonic current compensation method and device, active filter and storage medium |
| CN112448697A (en) * | 2020-10-30 | 2021-03-05 | 合肥工业大学 | Active filter optimization method and system based on quantum particle swarm optimization |
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