检索结果-内蒙古大学图书馆

Neutral point voltage balancing method and the influence of some parameters on capacitor voltage in three-level NPC converter

引用

International Conference on Advanced Engineering Theory and Applications 2013, AETA 2013

作者： Nam, Vo Xuan Giau, Le Van Manh Nho, Nguyen Van Trang, Tran Thanh Electronics Engineering Department Cao Thang College of Technology Ho Chi Minh City Viet Nam National Key Lab. of Digital Control and System Engineering University of Technology Vietnam National University Ho Chi Minh City Viet Nam Power Engineering Research Lab. University of Technology Vietnam National University Ho Chi Minh City Viet Nam Electrical Engineering Department Ho Chi Minh City Open University Viet Nam Electronics and Telecommunication Engineering Department Van Hien University Ho Chi Minh City Viet Nam

ISBN: (纸本)9783642419676

This paper presented a control method for balancing capacitor voltage of three-level neutral-point-diode-clamped (NPC) converter. This control method overcomes one of the main problems of this converter, which is the low frequency voltage oscillation that appears in the neutral point. The algorithm is based on Carrier-based Pulse Width Modulation (CPWM). This paper showed the influence of power factor, modulation index and offset limit on capacitor voltage. It also presented the optimal amplitude of offset voltage in some case of power factors and modulation indexes. © Springer-Verlag Berlin Heidelberg 2014.

关键词： Modulation

来源：评论

学校读者我要写书评

暂无评论

Variable Frequency Phase-Shift Modulation Technique for Single Stage Dual-Active-Bridge AC-DC Converter

Variable Frequency Phase-Shift Modulation Technique for Sing...

引用

International Conference on Power Electronics (ICPE)

作者： Dongxin Guo Panbao Wang Chunguang Ren Josep M. Guerrero School of Electrical Engineering and Automation Harbin Institute of Technology Harbin China Shanxi Key Lab. of Power System Operation and Control Taiyuan University of Technology Taiyuan China Department of Energy Technology Aalborg University Aalborg Denmark

This article proposes a variable frequency phase-shift modulation technique for single stage dual-active-bridge (DAB) AC-DC converter. This isolated single-stage single-phase converter consists of a DAB and a full bridge (FB) inverter. The proposed strategy applies a composite control strategy combining frequency modulation and extended phase shift (EPS) method to overcome the drawback of the non-linear power control of traditional phase-shift control scheme, which significantly reduces the complexity of the controller algorithm. Moreover, the synchronous inverter control applied to the back-end FB inverter is designed, which can realize the energy conversions in a single-stage, and a high frequency (HF) filter capacitor can replace the electrolytic capacitor at the output side DC-link. Thus, the safety of system operation improves and the power density of the system increases. Finally, simulation results confirm the validity and practical feasibility of the proposed control strategy.

关键词：

来源：评论

学校读者我要写书评

暂无评论

The study on size effect of fracture toughness of test of undisturbed frozen soils based on Gray Theory

The study on size effect of fracture toughness of test of un...

引用

2011 2nd International Conference on Mechanic Automation and control Engineering, MACE 2011

作者： Liu, Xiao-Zhou Liu, Peng Sun, Qiao Bai, Hui-Ren Key Laboratory for Prediction and Control on Complicated Structure System of Liaoning Province Dalian University Dalian China State Key Lab. of Frozen Soil Eng. Cold and Arid Regions Environ. and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

ISBN: (纸本)9781424494392

Based on the previous undisturbed frozen field test, the research and analysis on the Size effect of fracture toughness KIC of vertical crack and herringbone crack of undisturbed frozen soils specimens of test I is performed emphatically, and it is found the rules that it varies with volume change. Meanwhile, a theoretical prediction by using the Gray system Theory methods is made and the theoretical prediction results KIC has been gotten, which is compared with the results of the test and the error fits the accuracy requirement. Thus it has been made a meaningful exploration for the research method of Size effect of fracture toughness KIC of test I of undisturbed frozen soils. © 2011 IEEE.

关键词： Fracture toughness

来源：评论

学校读者我要写书评

暂无评论

Experimental research on fracture toughness II of undisturbed frozen soil

Experimental research on fracture toughness II of undisturbe...

引用

2nd International Conference on Multimedia Technology, ICMT 2011

作者： Liu, Xiao-Zhou Sun, Qiao Key Laboratory for Prediction and Control on Complicated Structure System of Liaoning Province Dalian University Dalian China State Key Lab. of Frozen Soil Eng. Cold and Arid Regions Environ. and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

ISBN: (纸本)9781612847740

Based on the study of fracture toughness II of frozen soil, the application of fracture toughness II is firstly used in undisturbed frozen soil in this paper. Because of undisturbed soil not vibrated and microstructures inside of the soil body not change, it is more realistic and more meaningful than remolded soil in lab.ratory. In the research, bend test stand was improved at first time, and drawing on prefabricated vertical cracks in rock fracture test to observe the cracks size by coloring. With the observations on layering frost heave of the local soil, the relations of frost heave, melt and time are obtained in different deep soil layers, so that the samples production and test temperature can be controlled strictly. The fracture toughness of four-pointbending vertical pre-cracked specimens of test IIof undisturbed frozen soil is obtained. Experimental results indicate that the undisturbed frozen soil mechanics experiment is completely availab.e, and it is feasible to measure the crack size with coloring technology, the fracture toughness II of undisturbed frozen soil is also obtained. © 2011 IEEE.

关键词： Fracture toughness

来源：评论

学校读者我要写书评

暂无评论

Period distribution analysis of some linear maps

引用

Communications in Nonlinear Science and Numerical Simulation 2012年第10期17卷 3848-3856页

作者： Fei Chen Xiaofeng Liao Kwok-wo Wong Qi Han Yang Li State Key Lab. of Power Transmission Equipment and System Security College of Computer Science Chongqing University Chongqing 400044 PR China Department of Electronic Engineering City University of Hong Kong Hong Kong PR China Department of Automatic Control and Systems Engineering The University of Sheffield UK

This paper discusses period properties of some linear maps which are employed in various applications such as image encryption, public key cryptography and watermarking. Conditions for the bijectiveness of such maps and the existence of a period are presented. Period structure is also given. Then, the recurrence equation theory is adopted to address the period distribution problem. Finally, a framework to solve the problem is proposed with a demonstration of its effectiveness and efficiency into some applications.

关键词： Linear map Period distribution Periodic orbit Dynamical system Cat map

来源：评论

学校读者我要写书评

暂无评论

Harmonic Current Detection and Reactive Power Compensation Method for Photovoltaic system Based on FBD Method

Harmonic Current Detection and Reactive Power Compensation M...

引用

IEEE Conference on Energy Internet and Energy system Integration (EI2)

作者： Lifeng Liu Dong Xie Duo Zhao Yanbing Jia Yongjun Yu Qiang Fan Yong Shen Weiwen Qi State Grid Shaoxing Power Supply Company Shaoxing China Shanxi Key Lab. of Power System Operation and Control Taiyuan University of Technology Taiyuan China Shaoxing Jianyuan Power Group Co. Ltd Shaoxing China

ISBN: (数字)9781728131375

ISBN: (纸本)9781728131382

In order to improve the equipment utilization of distributed photovoltaic power generation system, the harmonic and reactive currents generated by grid-connected photovoltaic system can be accurately detected and compensated. A phase-locked loop based on second-order generalized integrator (SOGI-PLL) is introduced into the traditional FBD current detection method to separate the positive and negative sequence components of unbalanced voltage and detect the phase and frequency of reference voltage more accurately. The simulation results show that the algorithm can reduce the computational complexity and increase the detection accuracy and steady-state performance.

关键词： Harmonic analysis Power harmonic filters Photovoltaic systems Phase locked loops Reactive power

来源：评论

学校读者我要写书评

暂无评论

control Strategy of Hybrid Energy Storage in Large-Scale Wind Farm

Control Strategy of Hybrid Energy Storage in Large-Scale Win...

引用

IEEE Conference on Energy Internet and Energy system Integration (EI2)

作者： Liang Huang Hao Chen Yanbing Jia Feng Tian Yun Bai Mengdie Li Shanxi Key Lab. of Power System Operation and Control Taiyuan University of Technology Taiyuan China State Grid Shanxi Electric Power Company Taiyuan Power Supply Company Taiyuan China Taiyuan University of Technology Taiyuan China

ISBN: (纸本)9781665434263

The large-scale access of renewable energy sources such as wind power will affect the operation and dispatch of the power system, and will affect the safe and stable of the power grid. The ESS has the ability to respond quickly, which can reduce the impact of wind power on the grid. Based on a hybrid energy storage with a certain capacity, a corresponding rolling optimization control strategy is proposed. Using batteries and super capacitor as energy storage media, an optimal control model targeting the state of charge of the hybrid energy storage system is established, and the solution is solved by a particle swarm optimization algorithm. The simulation example shows that a HESS with a certain capacity on the generation side can achieve a smooth grid connection. The control strategy proposed in this paper extends the service life of the battery.

关键词： Renewable energy sources Power supplies Capacitors Optimal control system integration Wind power generation Wind farms

来源：评论

学校读者我要写书评

暂无评论

A 4-Channel Ultrafast Wavelength-Swept REC-DFB Laser Array for Fiber Bragg Grating Interrogation

A 4-Channel Ultrafast Wavelength-Swept REC-DFB Laser Array f...

引用

2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings, ACP/POEM 2023

作者： Meng, Lingxin Dai, Pan Ban, Qilu Xu, Kaichuan Wang, Jiacheng Li, Zhen Wang, Feng Zeng, Jie Li, Shaobo Ma, Xiang Chen, Xiangfei Res. Center of Precision Photonics Integration and System Application of the Ministry of Education College of Engineering and Applied Sciences Nanjing University Key Lab. of Intelligent Optical Sensing and Manipulation of the Ministry of Education Engineering National Laboratory of Solid State Microstructures Nanjing210023 China Nanjing University of Aeronautics and Astronautics State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing210016 China The 54th Research Institute of China Electronics Technology Group Corporation Optical Communication Research and Development Center Shijiazhuang050081 China

ISBN: (纸本)9798350312614

We present a four-channel ultrafast wavelength-swept distributed feedback (DFB) semiconductor laser array based on the reconstruction-equivalent-chirp (REC) technique using instantaneous injection current modulation. With the aid of our designed laser driving circuit system consists of the microcontroller unit (MCU), field-programmable gate array (FPGA) and negative metal-oxide-semiconductor field effect transistors (n-MOSFETs), the precise pulse driving current for the 4-channel wavelength-swept REC-DFB laser array can be generated and a fast tuning of 16.424 nm within 10 μs is achieved. To further investigate the tuning performance of the proposed wavelength-swept laser source, we then applied it to the fiber Bragg grating (FBG) interrogation system and four FBG temperature sensor arrays were successfully demodulated. The development of high-efficient optical sensing systems heavily relies on the significance of the ultrafast wavelength-swept laser source, which has the potential to greatly enhance FBG interrogator performance in the future. © 2023 IEEE.

关键词： DFB laser array fast wavelength-swept fiber Bragg grating interrogation REC technique

来源：评论

学校读者我要写书评

暂无评论

An Improved Chimp Optimization Algorithm for Short-term Hydrothermal Scheduling

IAENG International Journal of Computer Science

引用

IAENG International Journal of Computer Science 2022年第3期49卷 666页

作者： Chen, Gonggui Wang, Shumin He, Yongsheng Shang, Wanfeng Long, Hongyu Key Laboratory of Industrial Internet of Things and Networked Control Ministry of Education Chongqing University of Posts and Telecommunications Chongqing400065 China Chongqing University of Posts and Telecommunications Chongqing400065 China State Grid Chongqing Electric Power Company Chongqing400015 China Guangdong Provincial Key Lab of Robotics and Intelligent System Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen Shenzhen518055 China Chongqing Key Laboratory of Complex Systems and Bionic Control Chongqing University of Posts and Telecommunications Chongqing400065 China

The short-term hydrothermal scheduling (STHS) is a complex non-linear, non-convex and high-dimensional mathematical optimization problem. Due to the fact that the original chimp optimization algorithm (ChOA) is likely to fall into local optimum and has the disadvantage of low population diversity, an improved chimp optimization algorithm (IChOA) is proposed to solve the STHS problem. Firstly, Logistic-Tent chaotic mapping is employed to initialize the population and increase the population diversity. Then a new nonlinear convergence factor is introduced to make the optimization search process more applicable to STHS problems. Next, particle swarm algorithm (PSO) and gravitational search algorithm (GSA) are combined to enhance the shortcoming and balance the global search ability and local exploration ability of ChOA. Moreover, Cauchy mutation and opposition-based learning strategy are supplemented as perturbation interference when the optimal position is not updated to improve the ability to leap out of the local optimum. Finally, a graded optimization strategy is adopted for the constraint handing of dynamic reservoir balance and thermal power balance. Three standard hydrothermal power systems are utilized to verify the practicability and validity of the proposed method. Results of simulations reveal that IChOA has significant competitive advantages in addressing the STHS problem. © 2022, IAENG International Journal of Computer Science. All Rights Reserved.

关键词： Particle swarm optimization (PSO)

来源：评论

学校读者我要写书评

暂无评论

Summary of Energy Storage systems and Renewable Energy Participation in AGC Research

Summary of Energy Storage Systems and Renewable Energy Parti...

引用

IEEE Conference on Energy Internet and Energy system Integration (EI2)

作者： Caiming Yang Hongfei Tao Xinrui Song Yanbing Jia Dong Xie Weiwen Qi Yongjun Yu Feng Zhao State Grid Shaoxing Power Supply Company Shaoxing China Shaoxing Jianyuan Power Group Co. Ltd. Shaoxing China Shanxi Key Lab. of Power System Operation and Control Taiyuan University of Technology Taiyuan China

ISBN: (数字)9781728131375

ISBN: (纸本)9781728131382

With the scarcity of fossil energy, the development of renewable energy is becoming more and more rapid. However, when new energy is integrated into the power grid, the inertia of the system is reduced and the stability of the system is lowered. This also poses a new challenge to frequency control, and energy storage as a technology that can quickly respond to system frequency changes is now widely concerned. This paper summarizes the domestic and international research status of energy storage and AGG capacity allocation and coordinated control through the influence of renewable energy on AGC. Finally, the development prospects of energy storage and participation in new energy integration into the power grid are prospected.

关键词： Frequency control Renewable energy sources Batteries Automatic generation control Power grids

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：