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A comprehensive review of wind power based power system frequency regulation

《能源前沿(英文)》 2023年 第17卷 第5期   页码 611-634 doi: 10.1007/s11708-023-0876-6

摘要: Wind power (WP) is considered as one of the main renewable energy sources (RESs) for future low-carbon and high-cost-efficient power system. However, its low inertia characteristic may threaten the system frequency stability of the power system with a high penetration of WP generation. Thus, the capability of WP participating in the system frequency regulation has become a research hotspot. In this paper, the impact of WP on power system frequency stability is initially presented. In addition, various existing control strategies of WP participating in frequency regulation are reviewed from the wind turbine (WT) level to the wind farm (WF) level, and their performances are compared in terms of operating principles and practical applications. The pros and cons of each control strategy are also discussed. Moreover, the WP combing with energy storage system (ESS) for system frequency regulation is explored. Furthermore, the prospects, future challenges, and solutions of WP participating in power system frequency regulation are summarized.

关键词: frequency regulation strategies     wind turbine generators     grid-forming control     model predictive control     energy storage system    

Load frequency control in deregulated power system with wind integrated system using fuzzy controller

Yajvender Pal VERMA, Ashwani KUMAR

《能源前沿(英文)》 2013年 第7卷 第2期   页码 245-254 doi: 10.1007/s11708-012-0218-6

摘要: This paper presents the analysis of load frequency control (LFC) of a deregulated two-area hydro-thermal power system using fuzzy logic controller, with doubly fed induction generators (DFIGs) integrated into both the control areas. The deregulation of power sector has led to the formation of new companies for generation, transmission and distribution of power. The conventional two-area power system is modified to study the effects of the bilateral contracts of companies on the system dynamics. Deregulation creates highly competitive and distributed control environment, and the LFC becomes even more challenging when wind generators are also integrated into the system. The overall inertia of the system reduces, as the wind unit does not provide inertia and isolates from the grid during disturbances. The DFIGs integrated provide inertial support to the system through modified inertial control scheme, and arrests the initial fall in frequency after disturbance. The inertial control responds to frequency deviations, which takes out the kinetic energy of the wind turbine for improving the frequency response of the system. To enhance the participation of the doubly fed induction generator (DFIG) in the frequency control, optimal values of the speed control parameters of the DFIG-based wind turbine have been obtained using integral square error (ISE) technique. The dynamics of the system have been obtained for a small load perturbation, and for contract violation using fuzzy controller.

关键词: frequency regulation     fuzzy controller     de-regulated power system     doubly fed induction generator (DFIG)     bilateral contract    

Parameter identification of interconnected power system frequency after trip-out of high voltage transmission

Xuzhan ZHOU,Shanshan LIU,Mingkun WANG,Yiping DAI,Yaohua TANG

《能源前沿(英文)》 2014年 第8卷 第3期   页码 386-393 doi: 10.1007/s11708-014-0323-9

摘要: Accurate modeling and parameters of high voltage (HV) grid are critical for stability research of system frequency. In this paper, simulation modeling of the system frequency was conducted of an interconnected power system with HV transmission lines in China. Based on recorded tripping data of the HV transmission lines, system parameters were identified by using genetic algorithm (GA). The favorable agreement between simulation results and recorded data verifies the validity of gird models and the accuracy of system parameters. The results of this paper can provide reference for the stability research of HV power grid.

关键词: high voltage (HV) grid     frequency stability parameter identification     primary frequency regulation (PFR)    

Design and analysis of a new high frequency double-servo direct drive rotary valve

Muzhi ZHU,Shengdun ZHAO,Jingxiang LI

《机械工程前沿(英文)》 2016年 第11卷 第4期   页码 344-350 doi: 10.1007/s11465-016-0406-x

摘要:

Researchers have investigated direct drive valve for many years to solve problems, such as fluid force imbalance and switching frequency. The structure of the rotary valve has received considerable research interest because of its favorable dynamic properties and simple structure. This paper studied the high frequency double-servo direct drive rotary valve (DDRV), and proposed a novel structure and drive method satisfying high reversing frequency and adequate quantity of flow. Servo motors are integrated into the valve by the innovative structure, which is designed to equilibrate the unbalanced radial fluid force with the symmetric distributed oil ports. Aside from the fast reversing function of the valve, the DDRV presented high performance in linearity of the flow quantity and valve opening as a result of the fan-shaped flow ports. In addition, a computational fluid dynamics (CFD) method based on Fluent was conducted to verify the flux regulation effect of the height change of the adjustable boss.

关键词: direct drive rotary valve     computational fluid dynamics (CFD)     flow regulation    

Moving policy and regulation forward for single-use plastic alternatives

《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1423-5

摘要: Single-use plastics are often used once or cannot be reused for extended periods. They are widely consumed with the rapid development of social economy. The waste generated by single-use plastics threatens ecosystem health by entering the environment and ultimately restricts sustainable human development. The innovation of sustainable and environmentally friendly single-use plastic alternative materials and the joint participation of governments, enterprises and the public are promising technologies and management approaches that can solve the problem of single-use plastics wastes. The development of single-use plastic alternative products can be promoted fundamentally only by improving relevant legislation and standards, providing differentiated industrial policies, encouraging scientific and technological innovation and expanding public participation.

关键词: Single-use plastic alternatives     Policy     Regulation     Sustainable development    

Phase transition regulation and caloric effect

《能源前沿(英文)》 2023年 第17卷 第4期   页码 463-477 doi: 10.1007/s11708-023-0860-1

摘要: Solid state refrigeration based on caloric effect is regarded as a potential candidate for replacing vapor-compression refrigeration. Numerous methods have been proposed to optimize the refrigeration properties of caloric materials, of which single field tuning as a relatively simple way has been systemically studied. However, single field tuning with few tunable parameters usually obtains an excellent performance in one specific aspect at the cost of worsening the performance in other aspects, like attaining a large caloric effect with narrowing the transition temperature range and introducing hysteresis. Because of the shortcomings of the caloric effect driven by a single field, multifield tuning on multicaloric materials that have a coupling between different ferro-orders came into view. This review mainly focuses on recent studies that apply this method to improve the cooling performance of materials, consisting of enlarging caloric effects, reducing hysteresis losses, adjusting transition temperatures, and widening transition temperature spans, which indicate that further progress can be made in the application of this method. Furthermore, research on the sign of lattice and spin contributions to the magnetocaloric effect found new phonon evolution mechanisms, calling for more attention on multicaloric effects. Other progress including improving cyclability of FeRh alloys by introducing second phases and realizing a large reversible barocaloric effect by hybridizing carbon chains and inorganic groups is described in brief.

关键词: phase transition regulation     caloric effect     solid state refrigeration    

The function and regulation of OTU deubiquitinases

Jiansen Du, Lin Fu, Yingli Sui, Lingqiang Zhang

《医学前沿(英文)》 2020年 第14卷 第5期   页码 542-563 doi: 10.1007/s11684-019-0734-4

摘要: Post-translational modification of cellular proteins by ubiquitin regulates numerous cellular processes, including cell division, immune responses, and apoptosis. Ubiquitin-mediated control over these processes can be reversed by deubiquitinases (DUBs), which remove ubiquitin from target proteins and depolymerize polyubiquitin chains. Recently, much progress has been made in the DUBs. In humans, the ovarian tumor protease (OTU) subfamily of DUBs includes 16 members, most of which mediate cell signaling cascades. These OTUs show great variation in structure and function, which display a series of mechanistic features. In this review, we provide a comprehensive analysis of current progress in character, structure and function of OTUs, such as the substrate specificity and catalytic activity regulation. Then we discuss the relationship between some diseases and OTUs. Finally, we summarize the structure of viral OTUs and their function in immune escape and viral survival. Despite the challenges, OTUs might provide new therapeutic targets, due to their involvement in key regulatory processes.

关键词: ubiquitin     OTU deubiquitinases     structure     function     regulation    

RECENT ADVANCES IN THE REGULATION OF CLIMACTERIC FRUIT RIPENING: HORMONE, TRANSCRIPTION FACTOR AND EPIGENETIC

《农业科学与工程前沿(英文)》 2021年 第8卷 第2期

摘要:

Fruit ripening is a complex developmental process made up of genetically programmed physiological and biochemical activities. It culminates in desirable changes in the structural and textural properties and is governed by a complex regulatory network. Much is known about ethylene, one of the most important metabolites promoting the ripening of climacteric fruits. However, the dynamic interplay between phytohormones also plays an important part. Additional regulatory factors such as transcription factors (TFs) and epigenetic modifications also play vital role in the regulation of climacteric fruit ripening. Here, we review and evaluate the complex regulatory network comprising interactions between hormones and the action of TFs and epigenetic modifications during climacteric fruit ripening.

 

关键词: climacteric fruit ripening / phytohormones / TFs / epigenetic modifications    

Molecular regulation and genetic improvement of seed oil content in

Wei HUA,Jing LIU,Hanzhong WANG

《农业科学与工程前沿(英文)》 2016年 第3卷 第3期   页码 186-194 doi: 10.15302/J-FASE-2016107

摘要: As an important oil crop and a potential bioenergy crop, L. is becoming a model plant for basic research on seed lipid biosynthesis as well as seed oil content, which has always been the key breeding objective. In this review, we present current progress in understanding of the regulation of oil content in , including genetics, biosynthesis pathway, transcriptional regulation, maternal effects and QTL analysis. Furthermore, the history of breeding for high oil content in is summarized and the progress in breeding ultra-high oil content lines is described. Finally, prospects for breeding high oil content cultivars are outlined.

关键词: breeding     maternal effects     oilseed rape     QTL    

Regulation of exogenous bFGF gene mediated by recombinant adeno-associated virus

Ke SONG, Nianjing RAO, Meiling CHEN, Yingguang CAO

《医学前沿(英文)》 2009年 第3卷 第2期   页码 158-163 doi: 10.1007/s11684-009-0042-5

摘要: The regulatory effect of basic fibroblast growth factor (bFGF) mediated by recombinant adeno-associated virus (AAV) was investigated. Recombinant plasmid pAAV-S3-bFGF, and pSVneo were co-transfected into BHK-21 cells, then the recombinant AAV genome was replicated and packaged with the helper virus HSV1-rc/ΔUL2. The titer of the recombinant rAAV2-tet-off-bFGF was determined by dot-blot assay. MC3T3-E1 cells were infected with rAAV2-tet-off-bFGF. Regulatory effects of Doxycycline (Dox) on bFGF and osteogenic factors were assayed quantitatively by real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The physical particle titer of rAAV2-tet-off-bFGF successfully constructed was 1.8×10 vector genomes/mL, and the virus could infect MC3T3-E1 cells effectively. In MC3T3-E1 cells treated with Dox, the expression levels of exogenous bFGF and osteogenic factors declined to varying degrees. It was concluded that rAAV2-tet-off-bFGF could infect MC3T3 cells efficiently, and this recombinant system could be regulated successfully by Dox .

关键词: tetracycline regulatory system     adeno-associated virus     basic fibroblast growth factor     gene regulation    

RECENT ADVANCES IN THE REGULATION OF CLIMACTERIC FRUIT RIPENING: HORMONE, TRANSCRIPTION FACTOR AND EPIGENETIC

Yinglin JI, Mingyang XU, Aide WANG

《农业科学与工程前沿(英文)》   页码 314-334 doi: 10.15302/J-FASE-2021386

摘要: Fruit ripening is a complex developmental process made up of genetically programmed physiological and biochemical activities. It culminates in desirable changes in the structural and textural properties and is governed by a complex regulatory network. Much is known about ethylene, one of the most important metabolites promoting the ripening of climacteric fruits. However, the dynamic interplay between phytohormones also plays an important part. Additional regulatory factors such as transcription factors (TFs) and epigenetic modifications also play vital role in the regulation of climacteric fruit ripening. Here, we review and evaluate the complex regulatory network comprising interactions between hormones and the action of TFs and epigenetic modifications during climacteric fruit ripening.

关键词: climacteric fruit ripening     phytohormones     TFs     epigenetic modifications    

Cutting CO emissions through demand side regulation: Implications from multi-regional input–output linear

《工程管理前沿(英文)》   页码 452-461 doi: 10.1007/s42524-022-0209-1

摘要: This study combines multi-regional input–output (MRIO) model with linear programming (LP) model to explore economic structure adjustment strategies for the reduction of carbon dioxide (CO2) emissions. A particular feature of this study is the identification of the optimal regulation sequence of final products in various regions to reduce CO2 emissions with the minimum loss in gross domestic product (GDP). By using China’s MRIO tables 2017 with 28 regions and 42 economic sectors, results show that reduction in final demand leads to simultaneous reductions in GDP and CO2 emissions. Nevertheless, certain demand side regulation strategy can be adopted to lower CO2 emissions at the smallest loss of economic growth. Several key final products, such as metallurgy, nonmetal, metal, and chemical products, should first be regulated to reduce CO2 emissions at the minimum loss in GDP. Most of these key products concentrate in the coastal developed regions in China. The proposed MRIOLP model considers the inter-relationship among various sectors and regions, and can aid policy makers in designing effective policy for industrial structure adjustment at the regional level to achieve the national environmental and economic targets.

关键词: CO2 emissions     demand side regulation     multi-regional input–output model     linear programming model    

Simulation analysis of pressure regulation of hydraulic thrust system on a shield tunneling machine

Zhibin LIU, Haibo XIE, Huayong YANG

《机械工程前沿(英文)》 2011年 第6卷 第3期   页码 377-382 doi: 10.1007/s11465-011-0226-y

摘要:

Hydraulic thrust system is an important system in a shield tunneling machine. Pressure regulation of thrust cylinders is the most important function for thrust system during tunnel excavation. In this paper, a hydraulic thrust system is explained, and a corresponding simulation model is carried out in order to study the system characteristics. Pressure regulation of a certain group’s cylinders has little influence on regulation of the other groups’ cylinders. The influence will not affect the process much during tunnel excavation. Pump displacement may have a greater effect on pressure regulation and oil supply flow rate should be adaptive to the system’s demand. A exacting situation is simulated to explain how pressure regulation works during tunnel excavation.

关键词: tunnel     hydraulic thrust system     pressure regulation     simulation    

Quorum sensing regulation methods and their effects on biofilm in biological waste treatment systems:

《环境科学与工程前沿(英文)》 2022年 第16卷 第7期 doi: 10.1007/s11783-021-1495-2

摘要:

• Quorum sensing enhancement and inhibition methods are summarized.

关键词: Quorum sensing     Biological waste treatment     Biofilm formation    

A frequency error estimation for isogeometric analysis of Kirchhoff–Love cylindrical shells

《结构与土木工程前沿(英文)》 doi: 10.1007/s11709-023-0006-x

摘要: A frequency error estimation is presented for the isogeometric free vibration analysis of Kirchhoff–Love cylindrical shells using both quadratic and cubic basis functions. By analyzing the discrete isogeometric equations with the aid of harmonic wave assumption, the frequency error measures are rationally derived for the quadratic and cubic formulations for Kirchhoff–Love cylindrical shells. In particular, the governing relationship of the continuum frequency for Kirchhoff–Love cylindrical shells is naturally embedded into the frequency error measures without the need of explicit frequency expressions, which usually are not trivial for the shell problems. In accordance with these theoretical findings, the 2nd and 4th orders of frequency accuracy are attained for the isogeometric schemes using quadratic and cubic basis functions, respectively. Numerical results not only thoroughly verify the theoretical convergence rates of frequency solutions, but also manifest an excellent magnitude match between numerical and theoretical frequency errors for the isogeometric free vibration analysis of Kirchhoff–Love cylindrical shells.

关键词: isogeometric analysis     Kirchhoff–Love cylindrical shell     free vibration     frequency error     convergence    

标题 作者 时间 类型 操作

A comprehensive review of wind power based power system frequency regulation

期刊论文

Load frequency control in deregulated power system with wind integrated system using fuzzy controller

Yajvender Pal VERMA, Ashwani KUMAR

期刊论文

Parameter identification of interconnected power system frequency after trip-out of high voltage transmission

Xuzhan ZHOU,Shanshan LIU,Mingkun WANG,Yiping DAI,Yaohua TANG

期刊论文

Design and analysis of a new high frequency double-servo direct drive rotary valve

Muzhi ZHU,Shengdun ZHAO,Jingxiang LI

期刊论文

Moving policy and regulation forward for single-use plastic alternatives

期刊论文

Phase transition regulation and caloric effect

期刊论文

The function and regulation of OTU deubiquitinases

Jiansen Du, Lin Fu, Yingli Sui, Lingqiang Zhang

期刊论文

RECENT ADVANCES IN THE REGULATION OF CLIMACTERIC FRUIT RIPENING: HORMONE, TRANSCRIPTION FACTOR AND EPIGENETIC

期刊论文

Molecular regulation and genetic improvement of seed oil content in

Wei HUA,Jing LIU,Hanzhong WANG

期刊论文

Regulation of exogenous bFGF gene mediated by recombinant adeno-associated virus

Ke SONG, Nianjing RAO, Meiling CHEN, Yingguang CAO

期刊论文

RECENT ADVANCES IN THE REGULATION OF CLIMACTERIC FRUIT RIPENING: HORMONE, TRANSCRIPTION FACTOR AND EPIGENETIC

Yinglin JI, Mingyang XU, Aide WANG

期刊论文

Cutting CO emissions through demand side regulation: Implications from multi-regional input–output linear

期刊论文

Simulation analysis of pressure regulation of hydraulic thrust system on a shield tunneling machine

Zhibin LIU, Haibo XIE, Huayong YANG

期刊论文

Quorum sensing regulation methods and their effects on biofilm in biological waste treatment systems:

期刊论文

A frequency error estimation for isogeometric analysis of Kirchhoff–Love cylindrical shells

期刊论文