CN116436273A - Control method and system for three-phase three-level inverter - Google Patents
Control method and system for three-phase three-level inverter Download PDFInfo
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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
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- H—ELECTRICITY
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- 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
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Abstract
The application provides a control method and a control system for a three-phase three-level inverter. The method comprises the following steps: sampling three-phase parameters of an inverter and converting the three-phase parameters into a two-phase static coordinate system, and obtaining a predicted value of output voltage by utilizing a model prediction recurrence formula and combining inverter voltage values under different switch combinations; recording a historical value of the output voltage, and obtaining an output voltage reference value through a second-order Lagrangian extrapolation formula; a virtual voltage vector is selected from the vector grouping that minimizes the cost function. Performing iterative computation on the virtual voltage vector in the same sector as the virtual voltage vector with the minimum cost function, and determining the voltage vector with the minimum cost function; and generating the 3P-3L inverter by using pulse width modulation according to the voltage vector which enables the cost function to be globally minimum. The method reduces output voltage harmonic waves and simplifies the design and calculation time of the controller. The direct-current side voltage and current sensor can be reduced, and the hardware cost is reduced.
Description
Technical Field
The application relates to the technical field of power electronic systems, in particular to a control method and a control system of a three-phase three-level inverter with self-balancing direct-current neutral point voltage.
Background
New energy power generation is becoming an important point of attention in the energy field, an inverter plays a role of converting direct current into alternating current, the inverter is a key device for new energy power generation, and control of the inverter is also becoming a technical research hotspot in the field. The three-level inverter is widely applied to new energy power generation and energy storage systems due to the advantages of small output voltage harmonic wave, high efficiency and the like. The controller design of a three-level inverter is critical to performance. Direct power controllers, proportional-integral controllers and proportional-resonant controllers have been research hot spots, and model predictive control has received extensive attention with the development of modern signal processors. Model predictive control typically sets control targets and cost functions to predict future states of controlled variables in a finite amount of time through a built model. In the inverter model predictive control, a combination of switches that minimizes a cost function is often selected for control. With the help of powerful signal processors, model predictive control tends to have better dynamic and steady state performance.
The balance of the neutral point voltage can be maintained, which affects the control effect of the three-phase three-level inverter. If the voltage oscillation of the neutral point is large, the voltage between the two capacitors at the direct current side changes, so that each power semiconductor device is subjected to larger voltage stress, and larger loss and even device damage are caused. In addition, voltage fluctuations at the neutral point also increase the harmonics of the inverter phase voltage output.
The traditional model predictive control algorithm uses a double-objective cost function, and the midpoint potential is restrained by adding corresponding weight factor items in the cost function. However, on one hand, the setting and tuning of the weight factors do not have a systematic method, and on the other hand, one more term to be considered in the cost function makes the voltage optimal term unavailable in some cases, so that the output harmonic content is increased.
Disclosure of Invention
In view of this, the present application aims to provide a method and a system for controlling a three-phase three-level inverter with self-balancing dc neutral point voltage, which can solve the existing problems in a targeted manner, and obtain 51 virtual voltage vectors that do not affect the neutral point voltage by combining the real voltage vectors, and the control method using these virtual voltage vectors does not need to consider the neutral point voltage any more.
Based on the above objects, the present application proposes a control method of a three-phase three-level inverter with self-balancing dc neutral-point voltage, comprising:
sampling three-phase parameters of an inverter and converting the three-phase parameters into a two-phase static coordinate system, and obtaining a predicted value of output voltage by utilizing a model prediction recurrence formula and combining inverter voltage values under different switch combinations;
recording a historical value of the output voltage, and obtaining an output voltage reference value through a second-order Lagrangian extrapolation formula;
selecting a virtual voltage vector from the vector group that minimizes the cost function;
performing iterative computation on the virtual voltage vector in the same sector as the virtual voltage vector with the minimum cost function, and determining the voltage vector with the minimum cost function;
and generating the 3P-3L inverter by using pulse width modulation according to the voltage vector which enables the cost function to be globally minimum.
Further, the three-phase parameters of the inverter include: inverter output current i x (k) Output voltage V o (k) Load current i load (k)。
Further, the model prediction recursion formula is as follows:
wherein T is s For the total time of all the actual voltage vectors, L is the inductance value, C is the capacitance value, V α，β (k+1) is the inverter voltage value, V oα，β (k+1) is a predicted value of the output voltage, i α，β (k+1) is an inverter current value, i oα，β (k+1) is a predicted value of the output current, i loadα，β (k) Is the load current value.
Further, the second-order Lagrangian extrapolation formula is as follows:
wherein,,
is the output voltage reference.
Further, the cost function G (j) is as follows:
further, the output side phase currents of the inverter a, b and c phases satisfy the following relationship:
i a +i b +i c ＝0
wherein i is a 、i b 、i c Output side phase currents of the inverter a phase, b phase and c phase, respectively.
Further, virtual voltage vector V vx The following relationship is satisfied:
wherein V is vx Representing model predicted voltage vectors, V i And t i Respectively represent the real voltage vectors used for synthesizing the virtual voltage vectors and the corresponding acting time, T s For the total time of action of all real voltage vectors, N is the number of vectors used.
Based on the above object, the present application further provides a three-phase three-level inverter control system with self-balancing dc neutral-point voltage, including:
the voltage prediction module is used for sampling three-phase parameters of the inverter and converting the three-phase parameters into a two-phase static coordinate system, and obtaining a predicted value of the output voltage by utilizing a model prediction recurrence formula and combining inverter voltage values under different switch combinations;
the voltage reference module is used for recording the historical value of the output voltage and obtaining an output voltage reference value through a second-order Lagrange extrapolation formula;
a cost function module, configured to select a virtual voltage vector that minimizes a cost function from the vector group;
the iterative computation module is used for carrying out iterative computation on the virtual voltage vector in the same sector as the virtual voltage vector which makes the cost function minimum, and determining the voltage vector which makes the cost function global minimum;
and the pulse width modulation module is used for generating the 3P-3L inverter by using pulse width modulation according to the voltage vector which enables the cost function to be the global minimum.
In general, the present application proposes a model predictive voltage control based on virtual voltage vectors, the main innovations and contributions can be summarized as: (1) The present application uses 51 virtual voltage vectors in total, and more alternative vectors result in reduced output voltage harmonics than the traditional 27 basic voltage vectors. (2) The neutral point potential of the virtual voltage vector used is kept balanced in one period, and the cost function does not need to restrict the neutral point potential again, so that the design and calculation time of the controller are simplified. (3) The two capacitor voltages at the direct current side are not changed in the control strategy, so that the voltage and current sensors at the direct current side can be reduced, and the hardware cost is reduced.
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In the drawings, the same reference numerals refer to the same or similar parts or elements throughout the several views unless otherwise specified. The figures are not necessarily drawn to scale. It is appreciated that these drawings depict only some embodiments according to the disclosure and are not therefore to be considered limiting of its scope.
Fig. 1 shows a schematic diagram of the actual voltage vector and vector equivalent effect on the neutral point of the present application.
Fig. 2 shows a virtual voltage vector diagram used in the present application according to an embodiment of the present application.
Fig. 3 shows a control block diagram of the present application.
Fig. 4 shows a simulation result diagram of the algorithm Simulink in the present application.
Fig. 5 shows a configuration diagram of a three-phase three-level inverter control system of direct-current neutral point voltage self-balancing according to an embodiment of the present application.
Fig. 6 shows a schematic structural diagram of an electronic device according to an embodiment of the present application.
Fig. 7 shows a schematic diagram of a storage medium according to an embodiment of the present application.
Detailed Description
The present application is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings.
It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.
Term interpretation:
three-phase three-level inverter: three-phase three-level inverters have three possible values for each phase output voltage, and common three-level inverters have neutral point clamped three-level inverters, cascaded H-bridge inverters, and the like.
Neutral point voltage: the neutral point voltage is the potential of the neutral point between the upper and lower capacitors on the dc side of the inverter. Whether the neutral point voltage can be balanced influences the control effect of the three-phase T-type inverter.
Model predictive voltage control (Model Predictive Voltage Control, MPVC): model predictive control is a class of control strategies. Its current control action is obtained by solving a finite time domain open loop optimal control problem at each sampling instant. The current state of the process is used as the initial state of the optimal control problem, and the solved optimal control sequence only implements the first control effect. This is the biggest difference from those algorithms that use pre-computed control laws. Essentially model predictive control solves an open loop optimal control problem. Its ideas are independent of the specific model, but implementation is model dependent.
The purpose of the application is to invent a method capable of improving the output voltage waveform of a three-phase three-level inverter and keeping the neutral point potential at the direct current side self-balancing.
In a three-phase three-level inverter, neutral point current i np Is the main factor affecting neutral point potential balance if i is within one sampling period np Non-zero results in an imbalance in the upper and lower capacitor voltages. The neutral point voltage oscillation can be realized by ensuring i in one period np Zero implementation. Based on the idea, the model prediction voltage vector based on the virtual voltage vector can be divided into a zero voltage vector, a small voltage vector, a medium voltage vector and a large voltage vector according to different magnitudes. The neutral point current when each voltage vector is used is shown in FIG. 1, where both the zero voltage vector and the large voltage vector are for i np There is no effect, and both the small voltage vector and the medium voltage vector have different effects. To ensure the neutral point current i of each period np Zero, while combining as many vectors as possible to reduce the harmonics of the output voltage current, the basic combination is adopted according to the following (1):
i a +i b +i c ＝0 (1)
wherein i is a 、i b 、i c Output side phase currents of the inverter a phase, b phase and c phase, respectively.
TABLE 1 virtual Voltage vector combinations as used herein
New virtual voltage vector V combined vx The following relationship is satisfied:
wherein V is vx Representing model predicted voltage vectors, V i And t i Respectively represent the real voltage vectors used for synthesizing the virtual voltage vectors and the corresponding acting time, T s For the total time of action of all real voltage vectors, N is the number of vectors used. Considering the effect of each basic vector on the neutral point voltage, the time of action of each basic vector in the present application should be equal, namely:
the combinations of all virtual voltage vectors are listed in table 1, while fig. 2 shows all virtual voltage vectors used.
A predictive voltage control model recurrence formula:
wherein T is s For the total time of all the actual voltage vectors, L is the inductance value, C is the capacitance value, V α，β (k+1) is the inverter voltage value, V oα，β (k+1) is a predicted value of the output voltage, i α，β (k+1) is an inverter current value, i oα，β (k+1) is a predicted value of the output current, i loadα，β (k) Is the load current value.
Second order langerhans extrapolation formula:
cost function G (j) and objective function V used in the present invention opt ：
As shown in fig. 3, the model predictive control based on the virtual voltage vector is implemented as follows:
s1, sampling three-phase parameters of an inverter and converting the three-phase parameters into a two-phase static coordinate system, wherein i x (k) For the inverter to output current, V o (k) To output voltage i load (k) Is the load current. Inverter voltage value V under different switch combinations by using model prediction recurrence formula (5) α，β (k+1) the predicted value V of the output voltage can be obtained oα，β (k+1)。
S2, recording a historical value of the output voltage, and obtaining an output voltage reference value through a second-order Lagrange extrapolation formula (6)
S3, grouping from vectors (V v6 、V v10 、V v14 、V v18 、V v22 、V v26 ) A virtual voltage vector that minimizes the cost function (7).
S4, performing iterative computation on the virtual voltage vector in the same sector as the voltage vector selected in the S3, and determining the voltage vector enabling the cost function (7) to be the global minimum.
S5, generating the 3P-3L inverter by using pulse width modulation according to the selected voltage vector.
In order to compare the conventional control strategy with the strategy proposed in the present application, a simulation analysis was performed in MATLAB/SIMULINK. Fig. 4 shows steady-state waveforms for two strategies when controlling the amplitude of the output voltage Vo to be 100V. In fig. 4, "perpendicular MPVC" is the prior art, and "programmed MPVC" is the present application. The Harmonic Order is a Harmonic Order. (a) a neutral point voltage; (b) output line voltage; (c) outputting a phase voltage; (d) output phase voltage harmonic analysis. It can be seen that under the condition that the weight factor of the midpoint potential is 0.8, the maximum value of the midpoint potential fluctuation of the traditional algorithm is about 2.4V, which is close to three times of the model prediction algorithm without using the weight factor. Meanwhile, the THD of the output voltage of the traditional algorithm is 1.2%, the THD of the algorithm provided by the application is 0.5%, and more voltage vectors are used for inhibiting harmonic waves to a certain extent.
The application embodiment provides a three-phase three-level inverter control system for self-balancing a dc neutral-point voltage, which is used for executing the three-phase three-level inverter control method for self-balancing a dc neutral-point voltage according to the embodiment, as shown in fig. 5, and the system includes:
the voltage prediction module 501 is configured to sample three-phase parameters of the inverter and convert the three-phase parameters into a two-phase stationary coordinate system, and obtain a predicted value of the output voltage by using a model prediction recurrence formula and combining the inverter voltage values under different switch combinations;
the voltage reference module 502 is configured to record a historical value of the output voltage, and obtain an output voltage reference value through a second-order lagrangian extrapolation formula;
a cost function module 503, configured to select a virtual voltage vector that minimizes a cost function from the vector group;
an iterative computation module 504, configured to perform iterative computation on a virtual voltage vector in the same sector as the virtual voltage vector that minimizes the cost function, and determine a voltage vector that minimizes the cost function globally;
a pulse width modulation module 505, configured to generate a 3P-3L inverter using pulse width modulation according to the voltage vector that globally minimizes the cost function.
The control system of the three-phase three-level inverter with the self-balancing direct-current neutral point voltage provided by the embodiment of the application and the control method of the three-phase three-level inverter with the self-balancing direct-current neutral point voltage provided by the embodiment of the application are the same in conception and have the same beneficial effects as the method adopted, operated or realized by the stored application program.
The embodiment of the application also provides an electronic device corresponding to the three-phase three-level inverter control method for self-balancing the DC neutral point voltage provided by the previous embodiment, so as to execute the three-phase three-level inverter control method for self-balancing the upper DC neutral point voltage. The embodiments of the present application are not limited.
Referring to fig. 6, a schematic diagram of an electronic device according to some embodiments of the present application is shown. As shown in fig. 6, the electronic device 20 includes: a processor 200, a memory 201, a bus 202 and a communication interface 203, the processor 200, the communication interface 203 and the memory 201 being connected by the bus 202; the memory 201 stores a computer program that can be run on the processor 200, and when the processor 200 runs the computer program, the three-phase three-level inverter control method for dc neutral-point voltage self-balancing provided in any of the foregoing embodiments of the present application is executed.
The memory 201 may include a high-speed random access memory (RAM: random Access Memory), and may further include a non-volatile memory (non-volatile memory), such as at least one disk memory. The communication connection between the system network element and at least one other network element is implemented via at least one communication interface 203 (which may be wired or wireless), the internet, a wide area network, a local network, a metropolitan area network, etc. may be used.
The processor 200 may be an integrated circuit chip with signal processing capabilities. In implementation, the steps of the above method may be performed by integrated logic circuits of hardware in the processor 200 or by instructions in the form of software. The processor 200 may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU for short), a network processor (Network Processor, NP for short), etc.; but may also be a Digital Signal Processor (DSP), application Specific Integrated Circuit (ASIC), an off-the-shelf programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware components. The disclosed methods, steps, and logic blocks in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present application may be embodied directly in hardware, in a decoded processor, or in a combination of hardware and software modules in a decoded processor. The software modules may be located in a random access memory, flash memory, read only memory, programmable read only memory, or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in the memory 201, and the processor 200 reads the information in the memory 201, and in combination with its hardware, performs the steps of the above method.
The electronic equipment provided by the embodiment of the application and the control method of the three-phase three-level inverter with the self-balancing direct-current neutral point voltage provided by the embodiment of the application have the same beneficial effects as the method adopted, operated or realized by the electronic equipment based on the same inventive concept.
The present embodiment also provides a computer readable storage medium corresponding to the dc neutral-point voltage self-balancing three-phase three-level inverter control method provided in the foregoing embodiment, referring to fig. 7, the computer readable storage medium is shown as an optical disc 30, and a computer program (i.e. a program product) is stored thereon, where the computer program, when executed by a processor, performs the dc neutral-point voltage self-balancing three-phase three-level inverter control method provided in any of the foregoing embodiments.
It should be noted that examples of the computer readable storage medium may also include, but are not limited to, a phase change memory (PRAM), a Static Random Access Memory (SRAM), a Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), a Read Only Memory (ROM), an Electrically Erasable Programmable Read Only Memory (EEPROM), a flash memory, or other optical or magnetic storage medium, which will not be described in detail herein.
The computer readable storage medium provided by the above embodiment of the present application has the same beneficial effects as the method adopted, operated or implemented by the application program stored in the computer readable storage medium, because the same inventive concept is adopted by the control method of the three-phase three-level inverter with the self-balancing direct-current neutral point voltage provided by the embodiment of the present application.
It should be noted that:
the algorithms and displays presented herein are not inherently related to any particular computer, virtual system, or other apparatus. Various general-purpose systems may also be used with the teachings herein. The required structure for a construction of such a system is apparent from the description above. In addition, the present application is not directed to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings of the present application as described herein, and the above description of specific languages is provided for disclosure of preferred embodiments of the present application.
In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the present application may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.
Similarly, it should be appreciated that in the foregoing description of exemplary embodiments of the application, various features of the application are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the application and aiding in the understanding of one or more of the various inventive aspects. However, the disclosed method should not be construed as reflecting the intention that: i.e., the claimed application requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this application.
Those skilled in the art will appreciate that the modules in the apparatus of the embodiments may be adaptively changed and disposed in one or more apparatuses different from the embodiments. The modules or units or components of the embodiments may be combined into one module or unit or component and, furthermore, they may be divided into a plurality of sub-modules or sub-units or sub-components. Any combination of all features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or units of any method or apparatus so disclosed, may be used in combination, except insofar as at least some of such features and/or processes or units are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.
Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features but not others included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the present application and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.
Various component embodiments of the present application may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that some or all of the functions of some or all of the components in a virtual machine creation system according to embodiments of the present application may be implemented in practice using a microprocessor or Digital Signal Processor (DSP). The present application may also be embodied as a device or system program (e.g., a computer program and a computer program product) for performing a portion or all of the methods described herein. Such a program embodying the present application may be stored on a computer readable medium, or may have the form of one or more signals. Such signals may be downloaded from an internet website, provided on a carrier signal, or provided in any other form.
It should be noted that the above-mentioned embodiments illustrate rather than limit the application, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The application may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The use of the words first, second, third, etc. do not denote any order. These words may be interpreted as names.
The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think of various changes or substitutions within the technical scope of the present application, and these should be covered in the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims (10)
1. A method for controlling a three-phase three-level inverter with self-balancing direct-current neutral point voltage, comprising the steps of:
sampling three-phase parameters of an inverter and converting the three-phase parameters into a two-phase static coordinate system, and obtaining a predicted value of output voltage by utilizing a model prediction recurrence formula and combining inverter voltage values under different switch combinations;
recording a historical value of the output voltage, and obtaining an output voltage reference value through a second-order Lagrangian extrapolation formula;
selecting a virtual voltage vector from the vector group that minimizes the cost function;
performing iterative computation on the virtual voltage vector in the same sector as the virtual voltage vector with the minimum cost function, and determining the voltage vector with the minimum cost function;
and generating the 3P-3L inverter by using pulse width modulation according to the voltage vector which enables the cost function to be globally minimum.
2. The method of claim 1, wherein the step of determining the position of the substrate comprises,
the three-phase parameters of the inverter include: inverter output current i x (k) Output voltage V o (k) Load current i load (k)。
3. The method of claim 2, wherein the step of determining the position of the substrate comprises,
the model prediction recurrence formula is as follows:
wherein T is s For the total time of all the actual voltage vectors, L is the inductance value, C is the capacitance value, V α,β (k+1) is the inverter voltage value, V oα,β (k+1) is a predicted value of the output voltage, i α,β (k+1) is an inverter current value, i oα,β (k+1) is a predicted value of the output current, i loadα,β (k) Is the load current value.
4. The method of claim 3, wherein the step of,
the second-order Lagrangian extrapolation formula is as follows:
wherein,,
is the output voltage reference.
5. The method of claim 4, wherein the step of determining the position of the first electrode is performed,
the cost function G (j) is as follows:
6. the method according to any one of claims 1 to 5, wherein,
the output side phase currents of the inverter a, b and c phases satisfy the following relationship:
i a +i b +i c ＝0
wherein i is a 、i b 、i c Output side phase currents of the inverter a phase, b phase and c phase, respectively.
7. The method according to any one of claims 1 to 5, wherein,
virtual voltage vector V vx The following relationship is satisfied:
wherein V is vx Representing model predicted voltage vectors, V i And t i Respectively represent the real voltage vectors used for synthesizing the virtual voltage vectors and the corresponding acting time, T s For the total time of action of all real voltage vectors, N is the number of vectors used.
8. A three-phase three-level inverter control system for dc neutral-point voltage self-balancing, comprising:
the voltage prediction module is used for sampling three-phase parameters of the inverter and converting the three-phase parameters into a two-phase static coordinate system, and obtaining a predicted value of the output voltage by utilizing a model prediction recurrence formula and combining inverter voltage values under different switch combinations;
the voltage reference module is used for recording the historical value of the output voltage and obtaining an output voltage reference value through a second-order Lagrange extrapolation formula;
a cost function module, configured to select a virtual voltage vector that minimizes a cost function from the vector group;
the iterative computation module is used for carrying out iterative computation on the virtual voltage vector in the same sector as the virtual voltage vector which makes the cost function minimum, and determining the voltage vector which makes the cost function global minimum;
and the pulse width modulation module is used for generating the 3P-3L inverter by using pulse width modulation according to the voltage vector which enables the cost function to be the global minimum.
9. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor runs the computer program to implement the method of any one of claims 1-7.
10. A computer readable storage medium having stored thereon a computer program, wherein the program is executed by a processor to implement the method of any of claims 1-7.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117614300A (en) * | 2024-01-23 | 2024-02-27 | 苏州大学 | Continuous model predictive control method for T-type three-level three-phase four-bridge arm inverter |
| CN117856651A (en) * | 2023-12-27 | 2024-04-09 | 苏州大学 | Limited set sliding mode prediction control method and system for single-phase LC filter inverter |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN117856651A (en) * | 2023-12-27 | 2024-04-09 | 苏州大学 | Limited set sliding mode prediction control method and system for single-phase LC filter inverter |
| CN117856651B (en) * | 2023-12-27 | 2024-07-09 | 苏州大学 | Limited set sliding mode prediction control method and system for single-phase LC filter inverter |
| CN117614300A (en) * | 2024-01-23 | 2024-02-27 | 苏州大学 | Continuous model predictive control method for T-type three-level three-phase four-bridge arm inverter |
| CN117614300B (en) * | 2024-01-23 | 2024-04-05 | 苏州大学 | Continuous model predictive control method for T-type three-level three-phase four-bridge arm inverter |
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