检索结果-内蒙古大学图书馆

Prediction of Instability Separation Modes and Its Application in Practical Dynamic Security Region

Transactions of Tianjin University 2007年第3期13卷 157-162页

作者：曾沅余贻鑫王红梅闵亮张沛 LEES T Key Laboratory of Power System Simulation and Control of Ministry of Education Tianjin University Electrical Power Research Institute

The transient critical boundary of dynamic security region (DSR) can be approximated by a few hyper planes correlated with instability separation modes. A method to fast predict instability separation modes is proposed for DSR calculation in power injection space. The method identifies coherent generation groups by the developed K-medoids algorithm, taking a similarity matrix derived from the reachability Grammian as the index. As an experimental result, reachability Grammian matrices under local injections are approximately invariant. It indicates that the generator coherency identifications are nearly consistent for different injections. Then instability separation modes can be predicted at the normal operating point, while average initial acceleration is considered as the measure of the critical generator group to amend the error. Moreover, based on these predicted instability separation modes, a critical point search strategy for DSR calculation is illustrated in the reduced injection space of the critical generators. The proposed method was evaluated using New England Test system, and the computation accuracy and speed in determining the practical DSR were improved.

关键词： instability separation mode dynamic security region K-medoids algorithm reachability Grammian

来源：评论

学校读者我要写书评

暂无评论

control of Virtual Synchronous Generator for Frequency Regulation Using a Coordinated Self-adaptive Method

引用

CSEE Journal of power and Energy systems 2024年第1期10卷 175-184页

作者： Hongwei Fang Zhiwei Yu School of Electrical and Information Engineering and Key Laboratory of Tianjin Electric Power System Simulation and Control Tianjin UniversityTianjin 300072China

power inverter adopting virtual synchronous generator(VSG)control can provide inertia support for distributed generation ***,it cannot take into account the dynamic regulation characteristics of ***,when the system encounters a sudden change in load or disturbance,the dynamic process of frequency regulation will be greatly *** view of this issue,an improved VSG control strategy based on a coordinated self-adaptive(CSA)method is *** time domain analysis method is used to study the influences of virtual inertia and damping parameter perturbation on the system steady and dynamic ***,in order to make the control strategy suitable for large load changes and suppress frequency variations beyond the limit,the secondary frequency modulation is introduced into the control *** the coordinated adaptive control of virtual inertia,virtual damping and frequency modulation,the dynamic performance of vSG frequency regulation can be obviously *** and experiment results have verified the effectiveness of the proposed CSA control strategy.

关键词： Coordinated self-adaptive method frequency regulation time domain analysis virtual synchronous generator

来源：评论

学校读者我要写书评

暂无评论

Wavelet-based data compression for wide-area measurement data of oscillations

引用

Journal of modern power systems and Clean Energy 2018年第6期6卷 1128-1140页

作者： Lin CHENG Xinchi JI Fang ZHANG He HUANG Song GAO State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua University State Grid Jiangsu Electric Power Company

This paper proposes a wavelet-based data compression method to compress the recorded data of oscillations in power systems for wide-area measurement systems. Actual recorded oscillations and simulated oscillations are compressed and reconstructed by the waveletbased data compression method to select the best wavelet functions and decomposition scales according to the criterion of the minimum compression distortion composite index, for a balanced consideration of compression performance and reconstruction accuracy. Based on the selections, the relationship between the oscillation frequency and the corresponding optimal wavelet and scale is discussed, and a piecewise linear model of the base-2 logarithm of the frequency and the order of the wavelet is developed, in which different pieces represent different scales. As a result, the wavelet function and decomposition scale can be selected according to the oscillation frequency. Compared with the wavelet-based data compression method with a fixed wavelet scale for disturbance signals and the real-time data compression method based on exception compression and swing door trending for oscillations, the proposed method can provide high compression ratios and low distortion rates.

关键词： Data compression Oscillation Wavelet transform Wide-area measurement system(WAMS)

来源：评论

学校读者我要写书评

暂无评论

Excitation Current and Vibration Characteristics of DC Biased Transformer

引用

CSEE Journal of power and Energy systems 2021年第3期7卷 604-613页

作者： Chao Pan Chengjian Wang Hao Su Key Laboratory of Modem Power System Simulation and Control&Renewable Energy Technology Ministry of Education(Northeast Electric Power University)Jilin 132012China

In practical engineering,DC disturbance will lead to excitation saturation and vibration intensification on transformer core,as well as affecting the normal operation of equipment and power *** to the problem,a new idea is proposed in this *** on the electromagnetic characteristics of DC biased transformer,excitation saturation and core vibration are studied by using excitation-vibration harmonic response analysis *** current is identified through electromagnetic coupling to characterize the excitation saturation ***,vibration harmonic response model is established to analyze core *** characteristics of DC biased Y/△transformer are *** variation of excitation current and core vibration at different DC levels are ***-vibration characteristics of three-phase group transformer and three-phase three-limb transformer are compared and *** experimental platform built,the correctness of simulation results is verified by experimental data,and the effectiveness of the proposed method can be proved.

关键词： DC disturbance excitation-vibration harmonic response Y/△transformer

来源：评论

学校读者我要写书评

暂无评论

An approach to determining the local boundaries of voltage stability region with wind farms in power injection space

引用

Science China(Technological Sciences) 2010年第12期53卷 3232-3240页

作者： MU YunFei & JIA HongJie key laboratory of power system simulation and control of Ministry of Education, Tianjin University, Tianjin 300072, China 1. Key Laboratory of Power System Simulation and Control of Ministry of Education Tianjin University Tianjin 300072 China

A new approach to determining the local boundaries of voltage stability region in power injection space (IVSR) for power system with wind farms is presented. It can be used for power system voltage stability analysis and on-line security assessment with considering the output uncertainty of the wind farms. Firstly, power flow tracing and double dispatching are used to determine the generators that are closely related to the wind farms, in order to balance the power fluctuations caused by the wind speed variation. Then, modal analysis is used to get the key generators to achieve an effective dimension reduction for IVSR. Finally, the forecasting output power (or wind speed) of wind farms is divided into several intervals. For each interval, the corresponding local IVSR boundaries can be calculated by the method based on small disturbance. Moreover, parallel process is used to accelerate the computing speed. The presented approach is validated by several power systems. It can be revealed that the approach can give the local IVSR boundaries at different wind speeds and has a good engineering application prospect.

关键词： voltage stability region power flow tracing modal analysis parallel process

来源：评论

学校读者我要写书评

暂无评论

Integrated generation–consumption dispatch based on compensation mechanism considering demand response behavior

引用

Journal of modern power systems and Clean Energy 2018年第5期6卷 1025-1041页

作者： Yumin ZHANG Xueshan HAN Li ZHANG Bo XU Mingqiang WANG Ming YANG Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong University State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Department of Electrical Engineering Tsinghua University

Demand response(DR) is important to account for behaviors of the demand side to yield an optimal dispatch result. However, it is difficult for energy suppliers to collect customers' private information unless there is an incentive mechanism for customers to do so. Therefore,this paper proposes a new integrated generation–consumption dispatch based on compensation mechanism considering DR behavior. Firstly, in light of the dayahead load forecast data, we deduce the utility function model of different customers. By subtracting generating units' operation cost from consumers' total utility, the dispatch model has a decentralized demand participant structure based on this utility function. The utility function is used to describe consumers' preferences and energy consumption behaviors. Secondly, an effective compensation mechanism is designed to ensure customers to select the level of compensation appropriate to their willingness to curtail load. Finally, a new dispatch model is proposed that incorporates the DR compensation mechanism into the generation–consumption dispatch model. The new model can improve the interaction of generation and consumption,and benefit both the energy supplier and its customers. The proposed model is piecewise linearized and solved by a mixed-integer linear programming method. It is tested on a six-bus system and the IEEE 118-bus system. simulation results show that the proposed model can realize both maximum social welfare and Pareto optimal results.

关键词： Compensation mechanism Demand response Demand utility function Integrated generation– consumption dispatch

来源：评论

学校读者我要写书评

暂无评论

Frequency-Feedback Based Islanding Detection Algorithm for Micro-Grid

引用

Transactions of Tianjin University 2008年第2期14卷 85-91页

作者：李永丽李盛伟摆世彬牛冲宣 Key Laboratory of Power System Simulation and Control of Ministry of Education Tianjin UniversityTianjin 300072China

The unintentional islanding of micro-grid may cause negative impacts on distribution loads and distributed generations,so it must be detected within the acceptable *** this paper a new islanding detection algorithm is *** algorithm introduces the frequency feedback method by the reactive power compensation to derive the frequency continuous shift. Accordingly,the islanding can be detected by monitoring the frequency within 0.1 *** simulation results prove that this algorithm has extremely small non-detection zone,and meanwhile it presents an excellent islanding detection speed as well.

关键词： distributed generation micro-grid islanding detection reactive power compensation

来源：评论

学校读者我要写书评

暂无评论

Fault Diagnosis Method of Rolling Bearing Based on MSCNN-LSTM

引用

Computers, Materials & Continua 2024年第6期79卷 4395-4411页

作者： Chunming Wu Shupeng Zheng Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Ministry of EducationNortheast Electric Power UniversityJilin132012China Ministry of Education Northeast Electric Power UniversityJilin132012China

Deep neural networks have been widely applied to bearing fault diagnosis systems and achieved impressive success *** address the problem that the insufficient fault feature extraction ability of traditional fault diagnosis methods results in poor diagnosis effect under variable load and noise interference scenarios,a rolling bearing fault diagnosis model combining Multi-Scale Convolutional Neural Network(MSCNN)and Long Short-Term Memory(LSTM)fused with attention mechanism is *** adaptively extract the essential spatial feature information of various sizes,the model creates a multi-scale feature extraction module using the convolutional neural network(CNN)learning *** learning capacity of LSTM for time information sequence is then used to extract the vibration signal’s temporal feature *** parallel large and small convolutional kernels teach the system spatial local *** gathers temporal global features to thoroughly and painstakingly mine the vibration signal’s characteristics,thus enhancing model ***,bearing fault diagnosis is accomplished by using the SoftMax *** experiment outcomes demonstrate that the model can derive fault properties entirely from the initial vibration *** can retain good diagnostic accuracy under variable load and noise interference and has strong generalization compared to other fault diagnosis models.

关键词： Bearing fault diagnosis convolutional neural network short-long-term memory network feature fusion

来源：评论

学校读者我要写书评

暂无评论

Modeling of Busbars in High power Neutral Point Clamped Three-Level Inverters

引用

Tsinghua Science and Technology 2008年第1期13卷 91-97页

作者：易荣赵争鸣钟玉林 State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical EngineeringTsinghua University

The busbars in high power neutral point clamped three-level inverters are modeled using the Maxwell Q3D Extractor software, which is based on the partial element equivalent circuits method. The equivalent circuits of the busbars and devices model are simulated in the electric simulator PSlM to analyze the effects of the parasitic inductance on the switching characteristics of the integrated gate commutated thyristor （IGCT） in different topology positions. The simulation results agree well with the measured impedance analyzer results and the IGCT test results, which proves the effectiveness of the modeling method for the large, complex busbars.

关键词： busbars parasitic inductance partial element equivalent circuits switching characteristics

来源：评论

学校读者我要写书评

暂无评论

Robust Voltage control Considering Uncertainties of Renewable Energies and Loads via Improved Generative Adversarial Network

引用

Journal of modern power systems and Clean Energy 2020年第6期8卷 1104-1114页

作者： Qianyu Zhao Wenlong Liao Shouxiang Wang Jayakrishnan Radhakrishna Pillai the Key Laboratory of Smart Grid of Ministry of Education and Tianjin Key Laboratory of Power System Simulation and Control Tianjin UniversityTianjinChina the Department of Energy Technology Aalborg UniversityAalborgDenmark

The fluctuation of output power of renewable energies and loads brings challenges to the scheduling and operation of the distribution *** this paper,a robust voltage control model is proposed to cope with the uncertainties of renewable energies and loads based on an improved generative adversarial network(IGAN).Firstly,both real and predicted data are used to train the IGAN consisting of a discriminator and a *** noises sampled from the Gaussian distribution are fed to the generator to generate a large number of scenarios that are utilized for robust voltage control after scenario ***,a new improved wolf pack algorithm(IWPA)is presented to solve the formulated robust voltage control model,since the accuracy of the solutions obtained by traditional methods is *** simulation results show that the IGAN can accurately capture the probability distribution characteristics and dynamic nonlinear characteristics of renewable energies and loads,which makes the scenarios generated by IGAN more suitable for robust voltage control than those generated by traditional ***,IWPA has a better performance than traditional methods in terms of convergence speed,accuracy,and stability for robust voltage control.

关键词： Robust voltage control uncertainty generative adversarial network wolf pack algorithm

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：