Weighting factor design based on SVR–MOPSO for finite set MPC operated power electronic converters

Yonglu Liu,Zhengmao Yang,Xubin Liu,Hanbing Dan,Wenjing Xiong,Tao Ling,Mei Su 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.7

Selecting weighting factors is a challenge for the finite set model predictive control (FS-MPC). Based on the support vector regression (SVR) algorithm and the multi-objective particle swarm optimization (MOPSO) algorithm, this paper proposes a new weighting factor design principle. SVR is used to establish the functional relationship between the input weighting factors and the output performance indexes (such as the average switching frequency (fsw) and the total harmonic distortion of the output voltage). Even in the case of small samples, this can provide accurate performance index estimates for any combination of weighting factors. The established SVR function is taken as the fitness function. Then, MOPSO is used to search for Pareto optimal weighting factor combinations. The proposed method can converge in a few steps and does not require tedious calculations. Moreover, it is applicable to optimization problem with two or more weighting factors for arbitrary topology models. It also provides a range of optimal weighting factor solution sets. Finally, the proposed methodology is verified on a practical weighting factor design problem in a FS-MPC regulated voltage source inverter. Experimental results confirm the correctness of the theoretical analysis.

Independent power decoupling method using minimum switch devices for single-phase current source converters

Liu, Yonglu,Tang, Shunxin,Wang, Hui,Ning, Guangfu,Xiong, Wengjing The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.9

Independent power decoupling (IPD) topologies are used to mitigate the twice-line-frequency ripple power in single-phase systems. Then, bulky passive capacitors or inductors can be removed. This paper proposes an improved IPD topology for single-phase current source converters (SCSCs) to remove the bulky DC rail inductor. It only adds one active switch and one diode. When compared with existing IPD circuits, the required switch devices are minimum and control is flexible. In addition, due to the fact that two identical capacitors are used to buffer the ripple power, the buffer capacitor voltage stress and DC current ripple are significantly reduced. This paper introduces the operation mode and switching states of the proposed topology. Then, the modelling and control strategy are introduced. Moreover, the designs of the passive components are presented. Finally, the effectiveness of the proposed topology is verified by constructing a low-power experimental prototype.

Quasi-classical Trajectory Calculation of the Chemical Reactions Ba+C₆H₅Br, m-C₆H₄CH₃Br

Xia, Wenwen,Liu, Yonglu,Zhong, Haiyang,Yao, Li Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.2

In this paper, the reactive dynamics properties of the reactions Ba + $C_6H_5Br$ and Ba + m-$C_6H_4CH_3Br$ were studied by means of the quasi-classical trajectory method based on the London-Eyring-Polanyi-Sato potential energy surfaces. The vibrational distributions, reaction cross sections, rotational alignments of the products BaBr all were obtained. The peak values of the vibrational distributions are located at $\nu$ = 0 for the reactions Ba + $C_6H_5Br$ and Ba + m-$C_6H_4CH_3Br$ when the collision energies are 1.09 and 1.10 eV, respectively. The reaction cross sections increase with the increasing collision energy, which changes from 0.6 to 1.5 eV. The product rotational alignments deviate from -0.5 and firstly increase and then decrease while the collision energy is increasing, just like that of Heavy+Light-Light system.

Quasi-classical Trajectory Calculation of the Chemical Reactions Ba+C6H5Br, m-C6H4CH3Br

Wenwen Xia,Yonglu Liu,Haiyang Zhong,Li Yao 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.2

In this paper, the reactive dynamics properties of the reactions Ba + C6H5Br and Ba + m-C6H4CH3Br were studied by means of the quasi-classical trajectory method based on the London-Eyring-Polanyi-Sato potential energy surfaces. The vibrational distributions, reaction cross sections, rotational alignments of the products BaBr all were obtained. The peak values of the vibrational distributions are located at ν = 0 for the reactions Ba + C6H5Br and Ba + m-C6H4CH3Br when the collision energies are 1.09 and 1.10 eV, respectively. The reaction cross sections increase with the increasing collision energy, which changes from 0.6 to 1.5 eV. The product rotational alignments deviate from −0.5 and firstly increase and then decrease while the collision energy is increasing, just like that of Heavy+Light-Light system.

A Single-Phase Current-Source Bidirectional Converter for V2G Applications

Han, Hua,Liu, Yonglu,Sun, Yao,Wang, Hui,Su, Mei The Korean Institute of Power Electronics 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.3

In this paper, a single-phase current-source bidirectional converter topology for V2G applications is proposed. The proposed converter consists of a single-phase current-source rectifier (SCSR) and an auxiliary switching network (ASN). It offers bidirectional power flow between the battery and the grid in the buck or boost mode and expands the output voltage range, so that it can be compatible with different voltage levels. The topology structure and operating principles of the proposed converter are analyzed in detail. An indirect control algorithm is used to realize the charging and discharging of the battery. Finally, the semiconductor losses and system efficiency are analyzed. Simulation and experimental results demonstrate the validity and effectiveness of the proposed topology.

Single-Phase Current-Source Bidirectional Converter for V2G Applications

Hua Han,Yonglu Liu,Yao Sun,Hui Wang,Mei Su 전력전자학회 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.3

In this paper, a single-phase current-source bidirectional converter topology for V2G applications is proposed. The proposed converter consists of a single-phase current-source rectifier (SCSR) and an auxiliary switching network (ASN). It offers bidirectional power flow between the battery and the grid in the buck or boost mode and expands the output voltage range, so that it can be compatible with different voltage levels. The topology structure and operating principles of the proposed converter are analyzed in detail. An indirect control algorithm is used to realize the charging and discharging of the battery. Finally, the semiconductor losses and system efficiency are analyzed. Simulation and experimental results demonstrate the validity and effectiveness of the proposed topology.

A Single-phase Buck-boost AC-AC Converter with Three Legs

Min Zhou,Yao Sun,Mei Su,Xing Li,Fulin Liu,Yonglu Liu 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

This paper proposes a single-phase buck-boost AC-AC converter. It consists of three legs with six switching units (each unit is composed of an active switch and a diode) and its input and output ports share a common ground. It can provide buck-boost voltage operation and immune from shoot-through problem. Since only two switching units are involved in the current paths, the conduction losses are low, which improves the system efficiency. The operation principle of the proposed circuit is firstly presented, and then, various operation conditions are introduced to achieve different output voltages with step-changed frequencies. Additionally, the parameters design and comparative analysis of the power losses are also given. Finally, experimental results verify the correctness of the proposed converter.

A Single-phase Buck-boost AC-AC Converter with Three Legs

Zhou, Min,Sun, Yao,Su, Mei,Li, Xing,Liu, Fulin,Liu, Yonglu The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

This paper proposes a single-phase buck-boost AC-AC converter. It consists of three legs with six switching units (each unit is composed of an active switch and a diode) and its input and output ports share a common ground. It can provide buck-boost voltage operation and immune from shoot-through problem. Since only two switching units are involved in the current paths, the conduction losses are low, which improves the system efficiency. The operation principle of the proposed circuit is firstly presented, and then, various operation conditions are introduced to achieve different output voltages with step-changed frequencies. Additionally, the parameters design and comparative analysis of the power losses are also given. Finally, experimental results verify the correctness of the proposed converter.