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安全性 2

控制释放 2

有效性 2

模型试验 2

水压力 2

肠道菌群 2

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DPP）；分布式功率转换器；开关电容转换器 1

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Impact of FACTS devices on exercising market power in deregulated electricity market

Shanmugam PRABHAKAR KARTHIKEYAN, I. JACOB RAGLEND, D. P. KOTHARI

《能源前沿（英文）》 2013年第7卷第4期页码 448-455 doi: 10.1007/s11708-013-0262-x

摘要： In power system studies, congestion in transmission lines and utilization of flexible alternating current transmission system (FACTS) devices are closely associated. These devices are very important due to their role in power delivery system enhancement. It is to be noted that the generation companies can exercise their market power which depends on the line flows, line constraints, generators’ location and its share to the individual loads. This issue cannot be overlooked as it creates monopoliness which is against the deregulated market policy. The objective of this paper is to study the impact of market power when FACTS devices like thyristor controlled switching capacitor (TCSC) and thyristor controlled phase angle regulator (TCPAR) are used under steady state operation. The market power is determined using nodal must-run share (NMRS) index for the standard IEEE 14-bus system with and without the above FACTS devices and the results obtained are compared. All the above simulations are conducted in a MATLAB 7.9-R2009b environment.

关键词： flexible alternating current transmission system (FACTS) thyristor controlled switching capacitor (TCSC) thyristor controlled phase angle regulator (TCPAR) market power must-run generation (MRG) nodal must-run share (NMRS)

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An interval type-2 fuzzy logic controller for TCSC to improve the damping of power system oscillations

Manoj Kumar PANDA, Gopinath PILLAI, Vijay KUMAR

《能源前沿（英文）》 2013年第7卷第3期页码 307-316 doi: 10.1007/s11708-013-0269-3

摘要： In this paper an interval type-2 fuzzy logic controller (IT2FLC) was proposed for thyristor controlled series capacitor (TCSC) to improve power system damping. For controller design, memberships of system variables were represented using interval type-2 fuzzy sets. The three-dimensional membership function of type-2 fuzzy sets provided additional degree of freedom that made it possible to directly model and handle uncertainties. Simulations conducted on a single machine infinite bus (SMIB) power system showed that the proposed controller was more effective than particle swarm optimization (PSO) tuned and type-1 fuzzy logic (T1FL) based damping controllers. Robust performance of the proposed controller was also validated at different operating conditions, various disturbances and parameter variation of the transmission line parameters.

关键词： power system oscillations thyristor controlled series capacitor (TCSC) type-2 fuzzy logic system interval type-2 fuzzy logic controller (IT2FLC)

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Demand response based congestion management in a mix of pool and bilateral electricity market model

Ashwani KUMAR, Charan SEKHAR

《能源前沿（英文）》 2012年第6卷第2期页码 164-178 doi: 10.1007/s11708-012-0187-9

摘要： The independent system operator (ISO) is a key element in the deregulated structure with one of the responsibilities of transmission congestion management (CM). The ISO opts market based solutions to manage congestion receiving bids from generation companies (GENCOs) as well as distribution companies (DISCOMs) to reschedule their generation and relocate demand. The nodal prices increases during the congestion hours and the demand response to nodal prices will be an effective tool for the control of congestion. In this paper, demand response-based CM has been proposed for a mix of pool and bilateral electricity market model. The linear bid curves have been considered for demand bids to respond to the congestion in the network. The bilateral demand has been obtained with minimum deviations in their preferred schedule. The impact of flexible alternating current transmission system (FACTS) devices viz static var compensator (SVC) and thyristor controlled series compensator (TCSC) has also been considered for demand management during congestion. Multi-line congestion cases have been considered to study the impact on demand response without and with FACTS devices. The proposed approach has been tested on the IEEE 24 bus test system.

关键词： bid function congestion management (CM) demand response pool+bilateral electricity market static var compensator (SVC) thyristor controlled series compensator (TCSC)

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使用基于多目标粒子群算法多层自适应模糊推理系统晶闸管控制串联电容器补偿技术的互联多源电力系统动态稳定性增强器 Article

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《信息与电子工程前沿（英文）》 2017年第18卷第3期页码 394-409 doi: 10.1631/FITEE.1500317

摘要：本文采用了一种隶属于FACTSs族的晶闸管可控串联补偿器（thyristor-controlled series compensator, TCSC），来增强互联电力系统多源的整体动态性能。为此，我们使用一种分层自适应神经模糊推理系统控制器－晶闸管可控串联补偿器（hierarchical adaptive neuro-fuzzy inference system controller-TCSC, HANFISC-TCSC）在多区域互联电力系统中解决了两个重要的问题，即低频振荡和结线功率交换的偏差。本文对所提出的HANFISC-TCSC效能进行了精确评估，并在两个不同的互联电力系统（即双区域水柴油热和三区域水热发电系统）中，将其与传统的MOPSO-TCSC算法进行了对比。两个电力系统中仿真结果表明都可明确证实，与传统MOPSO-TCSC算法相比，HANFISC-TCSC具有更高性能。

关键词：分层自适应神经模糊推理系统控制器；晶闸管控制串联电容器补偿技术；自动发电控制（AGC）；多目标粒子群优化算法；电力系统动态稳定性；相互联系的多源电力系统

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收回说明：使用基于多目标PSO的分层ANFIS控制器-TCSC增强互连多电源系统的动态稳定性 Retraction Note

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《信息与电子工程前沿（英文）》 2019年第20卷第5期 doi: 10.1631/FITEE.19r0001

摘要： None

关键词： None

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NiCo2O4@quinone-rich N–C core–shell nanowires as composite electrode for electric double layer capacitor

《化学科学与工程前沿（英文）》 2023年第17卷第4期页码 373-386 doi: 10.1007/s11705-022-2223-6

摘要： The bind-free carbon cloth-supported electrodes hold the promises for high-performance electrochemical capacitors with high specific capacitance and good cyclic stability. Considering the close connection between their performance and the amount of carbon material loaded on the electrodes, in this work, NiCo₂O₄ nanowires were firstly grown on the substrate of active carbon cloth to provide the necessary surface area in the longitudinal direction. Then, the quinone-rich nitrogen-doped carbon shell structure was formed around NiCo₂O₄ nanowires, and the obtained composite was used as electrode for electric double layer capacitor. The results showed that the composite electrode displayed an area-specific capacitance of 1794 mF∙cm^–2 at the current density of 1 mA∙cm^–2. The assembled symmetric electric double layer capacitor achieved a high energy density of 6.55 mW∙h∙cm^–3 at a power density of 180 mW∙cm^–3. The assembled symmetric capacitor exhibited a capacitance retention of 88.96% after 10000 charge/discharge cycles at the current density of 20 mA∙cm^–2. These results indicated the potentials in the preparation of the carbon electrode materials with high energy density and good cycling stability.

关键词： carbon cloth NiCo₂O₄ nanowires core−shell structure quinone-rich electric double layer capacitor

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Stress induced polarization switching and coupled hysteretic dynamics in ferroelectric materials

Linxiang WANG, Roderick MELNIK, Fuzai LV

《机械工程前沿（英文）》 2011年第6卷第3期页码 287-291 doi: 10.1007/s11465-011-0230-2

摘要：

The dynamic responses of ferroelectric materials upon external mechanical and electrical stimulations are inherently nonlinear and coupled. In the current paper, a macroscopic differential model is constructed for the coupled hysteretic dynamics via modeling the orientation switching induced in the materials. A non-convex potential energy is constructed with both mechanic and electric field contributions. The governing equations are formulated as nonlinear ordinary differential equations by employing the Euler-Lagrange equation, and can be easily recast into a state space form. Hysteresis loops associated with stress induced polarization switching and butterfly-shaped behavior in ferroelectric materials are also successfully captured. The effects of mechanical loadings on the electrically induced switching are numerically investigated, as well as the mechanically-induced switching with various bias electric fields.

关键词： differential model state space electromechanical switching butterfly effects hysteresis

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Experimental investigation of a novel micro gas turbine with flexible switching function for distributed

Xiaojing LV, Weilun ZENG, Xiaoyi DING, Yiwu WENG, Shilie WENG

《能源前沿（英文）》 2020年第14卷第4期页码 790-800 doi: 10.1007/s11708-020-0691-2

摘要： Micro gas turbine (MGT) is widely used in small-scale distributed power systems because of its low emissions and fuel flexibility. However, the under-utilization of its exhaust heat and the low electric efficiency are the main bottlenecks that restrict its application. Additionally, the flexible switching between the power generated by the MGT and the power grid is also a key factor for keeping the secure operation of a distributed power station. Therefore, this paper conducted some experimental investigations of a 30 kW MGT to provide reference solutions for the above issues. This MGT is located at Shanghai Jiao Tong University (SJTU), which is designed by the Gas Turbine Research Institute of SJTU, and is manufactured by a turbo-machinery factory in Chongqing, China. The demonstration prototype is mainly composed of a single stage centrifugal compressor, a radial turbine, a combustor, a high-speed permanent magnet generator, and a control system. The results show that the MGT can achieve steady operation at a low rotational speed from 10000 r/min to 34000 r/min in the case of using oil lubricated bearings, which can greatly reduce the economic cost compared with the use of air bearings. At the same time, the ignition success rate of combustion chamber (CC) reaches 98% at a low rotational speed, and a wide range of stable combustion area can be obtained, because of the novel design method of combustor by referencing the way applied in an axial flow aero-engine. The MGT generating set can achieve functions, such as starting up, ignition, stable operation, loaded operation, grid-connection and stopping. This system also can realize flexibly switching from the start motor mode to the generator mode, and from grid-connected mode to off-grid mode, because the innovative multi-state switching control system is adopted. The above research work can make our state master independent intellectual property rights of micro gas turbine, rather than continue to be subject to the technological monopoly of the developed states, which can provide theoretical and experimental support for the industrialization of MGT in China.

关键词： gas turbine flexible switching system control system distributed power system emission test

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An improved delta-star switching scheme for reactive power saving in three-phase induction motors

P. RAJA,N. KUMARESAN,M. SUBBIAH

《能源前沿（英文）》 2014年第8卷第3期页码 364-370 doi: 10.1007/s11708-014-0324-8

摘要： It is proposed that a capacitor can be connected permanently across each phase winding of a three-phase induction motor along with the conventional delta-star switching, for further saving in VARh at reduced loads on the motor. The method of choosing a suitable value for the capacitor and the criteria to be adopted for calculating the power output at which the star to delta switching is to be made are also explained. The experimental results on a 3-phase, 4-pole, 415 V, 50 Hz, 3.3 kW induction motor verify the advantages in adding the capacitor to the phase winding of the motor. Compared to using only a single delta connected stator winding or a delta-star switching, the advantages of the proposed addition of a capacitor, are also demonstrated through a case study conducted on a 400 V, 250 kW motor. Any further improvement in grid side power factor can be achieved by employing a static synchronous compensator (STATCOM) of reduced VAR rating.

关键词： delta-star switching induction motor power factor steady-state analysis

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Synthesis and characterization of biocompatible polyurethanes for controlled release of hydrophobic and

Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG

《化学科学与工程前沿（英文）》 2014年第8卷第4期页码 498-510 doi: 10.1007/s11705-014-1451-9

摘要： Design of biocompatible and biodegradable polymer systems for sustained and controlled release of bioactive agents is critical for numerous biomedical applications. Here, we designed, synthesized, and characterized four polyurethane carrier systems for controlled release of model drugs. These polyurethanes are biocompatible and biodegradable because they consist of biocompatible poly(ethylene glycol) or poly(caprolactone diol) as soft segment, linear aliphatic hexamethylene diisocyanate or symmetrical aliphatic cyclic dicyclohexylmethane-4,4′-diisocyanate as hard segment, and biodegradable urethane linkage. They were characterized with Fourier transform infrared spectroscopy, atomic force microscope, and differential scanning calorimetry, whereas their degradation behaviors were investigated in both phosphate buffered saline and enzymatic solutions. By tuning polyurethane segments, different release profiles of hydrophobic and hydrophilic drugs were obtained in the absence and presence of enzymes. Such difference in release profiles was attributed to a complex interplay among structure, hydrophobicity, and degradability of polyurethanes, the size and hydrophobicity of drugs, and drug-polymer interactions. Different drug-polyurethane combinations modulated the distribution and location of the drugs in polymer matrix, thus inducing different drug release mechanisms. Our results highlight an important role of segmental structure of the polyurethane as an engineering tool to control drug release.

关键词： phase structure degradation polyurethanes controlled release drug delivery

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A novel soft-switching twin arc pulse MAG welding inverter

WANG Zhenmin, XUE Jiaxiang, WANG Fuguang, HUANG Shisheng

《机械工程前沿（英文）》 2007年第2卷第2期页码 224-227 doi: 10.1007/s11465-007-0039-1

摘要： The high-speed double wire pulse metal gas arc (MAG) welding process possesses advantages of automation and high efficiency and quality. Thus, it attracts much more attention nowadays. To meet the requirements of the double wire pulse MAG welding process, a novel double wire pulse MAG welding inverter integrated with technologies, such as soft-switching, double closed loop control, and synchronic control, is produced. A complete performance test was done for the pulsed MAG welding power supply by using a computer testing platform. The results of the experiment indicate that the novel welding inverter has an excellent performance both in the dynamic and the static characteristics. Also, the synchronic control between the master inverter and the slave inverter is reliable.

关键词： high-speed control computer experiment indicate platform

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国内首台ATM交换机研制及其组网实践

雷振明

《中国工程科学》 2000年第2卷第2期页码 53-55

摘要：

国内首台ATM（异步转送方式）交换机BTC-9500的研制于1995年完成，并配合国内宽带试验网络的建设，进行了大量的组网试验、设计改进和发展工作。目前，该设备已经由国内最大的电信设备制造商之一——上海贝尔公司生产销售，并且用于装备中国电信宽带骨干网的全部核心节点。根据组网实践中发现的问题，提出了在同一个交换结构内同时实现ATM信元交换和IP数据报交换的方案，并在BTC-9500中予以实现，达到了大大节省设备、简化网络和提高网络速度的多重目的，将研究范围逐渐拓宽到更大的宽带通信领域，提出了对于新一代电信网络发展的一些看法。

关键词：通信交换异步转送方式（ATM）

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基于混沌电路电容器连接的微分耦合同步 Regular Papers

Yu-meng XU, Zhao YAO, Aatef HOBINY, Jun MA

《信息与电子工程前沿（英文）》 2019年第20卷第4期页码 571-583 doi: 10.1631/FITEE.1800499

摘要：非线性振子和电路常用于研究耦合同步和一致性问题。完全同步是指所有振子保持相同幅度和相位，主要发生在完全相同振子之间。相位同步是指振子保持步调节律同步而幅度不同。对于无维动力学系统和振子，同步依赖于耦合变量的选择和耦合方式。非线性电路中电阻常用于连接两个或以上电路，触发电压耦合可对耦合电路反馈调制。本文采用电容器耦合两个Pikovsk-Rabinovich(PR)电路，这种电场耦合机制为微分耦合提供了依据。讨论了对称性和错位耦合下两个混沌电路的同步稳定性问题。在电阻耦合下，两个混沌电路容易完全同步。进一步讨论电容器耦合，发现当耦合电容器选择合适电容值时，两个耦合电路同步可被有效控制，且耦合电容器能量流有助于对同步的调控。混沌电路的同步实现和耦合通道有关，如对称性耦合容易完全同步，错位耦合有利于相位同步。电容器对应电场耦合能降低耦合器件能量（焦耳热）消耗，加强两个耦合电路能量输运和交换，从而实现混沌电路同步。

关键词：同步；电压耦合；混沌电路；电容器耦合

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Size-controlled green synthesis of silver nanoparticles assisted by L-cysteine

Wenchao Zhang,Lin Zhang,Yan Sun

《化学科学与工程前沿（英文）》 2015年第9卷第4期页码 494-500 doi: 10.1007/s11705-015-1527-1

摘要： A green and size-controlled synthesis of silver nanoparticles (Ag NPs) in aqueous solution with the assistance of L-cysteine is presented. The size of Ag NPs decreases with the increase of L-cysteine concentration, and thus can be controlled by adjusting L-cysteine concentration. TEM analysis shows that Ag NPs with an average size of 3 nm can be produced in the presence of 1.0 mmol/L L-cysteine, about one sixth of the size of Ag NPs obtained in the absence of L-cysteine (17 nm). The as-synthesized silver colloidal solution is stable and can be stored at room temperature for at least two months without any precipitation. This L-cysteine assisted method is simple, feasible and efficient, and would facilitate the production and application of Ag NPs.

关键词： nanoparticles silver L-cysteine size distribution synthesis

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Analysis and stabilization control of a voltage source controlled wind farm under weak grid conditions

《能源前沿（英文）》 2022年第16卷第6期页码 943-955 doi: 10.1007/s11708-021-0793-5

摘要： This paper investigates and discusses the interaction stability issues of a wind farm with weak grid connections, where the wind turbines (WTs) are controlled by a new type of converter control strategy referred to as the voltage source (VS) control. The primary intention of the VS control method is to achieve the high-quality inertial response capability of a single WT. However, when it is applied to multiple WTs within a wind farm, its weak-grid performance regarding the stability remains concealed and needs to be clarified. To this end, a frequency domain model of the wind farm under the VS control is first developed. Based on this model and the application of a stability margin quantification index, not only the interactions between the wind farm and the weak grid but also those among WTs will be systematically assessed in this paper. A crucial finding is that the inertial response of VS control has negative impacts on the stability margin of the system, and the dominant instability mode is more related to the interactions among the WTs rather than the typical grid-wind farm interaction. Based on this knowledge, a stabilization control strategy is then proposed, aiming for stability improvements of VS control while fulfilling the demand of inertial responses. Finally, all the results are verified by time-domain simulations in power systems computer aided design/electromagnetic transients including DC(PSCAD/EMTDC).

关键词： weak grids voltage source (VS) control wind turbine (WT) stabilization control wind farm inertial response