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Rural Power System Load Forecast Based on Principal Component Analysis 被引量:7
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作者 Fang Jun-long Xing Yu +2 位作者 Fu Yu Xu Yang Liu Guo-liang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第2期67-72,共6页
Power load forecasting accuracy related to the development of the power system. There were so many factors influencing the power load, but their effects were not the same and what factors played a leading role could n... Power load forecasting accuracy related to the development of the power system. There were so many factors influencing the power load, but their effects were not the same and what factors played a leading role could not be determined empirically. Based on the analysis of the principal component, the paper forecasted the demands of power load with the method of the multivariate linear regression model prediction. Took the rural power grid load for example, the paper analyzed the impacts of different factors on power load, selected the forecast methods which were appropriate for using in this area, forecasted its 2014-2018 electricity load, and provided a reliable basis for grid planning. 展开更多
关键词 load principal component analysis FORECAST rural power system
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Long-term system load forecasting based on data-driven linear clustering method 被引量:18
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作者 Yiyan LI Dong HAN Zheng YAN 《Journal of Modern Power Systems and Clean Energy》 SCIE EI 2018年第2期306-316,共11页
In this paper, a data-driven linear clustering(DLC) method is proposed to solve the long-term system load forecasting problem caused by load fluctuation in some developed cities. A large substation load dataset with a... In this paper, a data-driven linear clustering(DLC) method is proposed to solve the long-term system load forecasting problem caused by load fluctuation in some developed cities. A large substation load dataset with annual interval is utilized and firstly preprocessed by the proposed linear clustering method to prepare for modelling.Then optimal autoregressive integrated moving average(ARIMA) models are constructed for the sum series of each obtained cluster to forecast their respective future load. Finally, the system load forecasting result is obtained by summing up all the ARIMA forecasts. From error analysis and application results, it is both theoretically and practically proved that the proposed DLC method can reduce random forecasting errors while guaranteeing modelling accuracy, so that a more stable and precise system load forecasting result can be obtained. 展开更多
关键词 Long-term system load forecasting Datadriven LINEAR clustering AUTOREGRESSIVE integrated moving average(ARIMA) Error analysis
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Resilient Fixed-Order Distributed Dynamic Output Feedback Load Frequency Control Design for Interconnected Multi-Area Power Systems 被引量:4
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作者 Ali Azarbahram Amir Amini Mahdi Sojoodi 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第5期1139-1151,共13页
The paper proposes a novel H∞ load frequency control(LFC) design method for multi-area power systems based on an integral-based non-fragile distributed fixed-order dynamic output feedback(DOF) tracking-regulator cont... The paper proposes a novel H∞ load frequency control(LFC) design method for multi-area power systems based on an integral-based non-fragile distributed fixed-order dynamic output feedback(DOF) tracking-regulator control scheme. To this end, we consider a nonlinear interconnected model for multiarea power systems which also include uncertainties and timevarying communication delays. The design procedure is formulated using semi-definite programming and linear matrix inequality(LMI) method. The solution of the proposed LMIs returns necessary parameters for the tracking controllers such that the impact of model uncertainty and load disturbances are minimized. The proposed controllers are capable of receiving all or part of subsystems information, whereas the outputs of each controller are local. These controllers are designed such that the resilient stability of the overall closed-loop system is guaranteed. Simulation results are provided to verify the effectiveness of the proposed scheme. Simulation results quantify that the distributed(and decentralized) controlled system behaves well in presence of large parameter perturbations and random disturbances on the power system. 展开更多
关键词 Dynamic OUTPUT FEEDBACK CONTROL interconnected multi-area POWER systems load frequency CONTROL linear matrix INEQUALITIES POWER system CONTROL
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Decentralized Excitation Control of Multi-machine Multi-load Power Systems Using Hamiltonian Function Method 被引量:10
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作者 LIU Yan-Hong LI Chun-Wen WANG Yu-Zhen 《自动化学报》 EI CSCD 北大核心 2009年第7期919-925,共7页
关键词 哈密顿函数方法 电力系统 微分代数 分析方法
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Load Dependent Series-Parallel Systems with Common Bus Performance Sharing Mechanism 被引量:1
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作者 肖辉 彭锐 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期770-773,共4页
A series-parallel system was proposed with common bus performance sharing in which the performance and failure rate of the element depended on the load it was carrying. In such a system,the surplus performance of a su... A series-parallel system was proposed with common bus performance sharing in which the performance and failure rate of the element depended on the load it was carrying. In such a system,the surplus performance of a sub-system can be transmitted to other deficient sub-systems. The transmission capacity of the common bus performance sharing mechanism is a random variable. Effects of load on element performance and failure rate were considered in this paper. A reliability evaluation algorithm based on the universal generating function technique was suggested. Numerical experiments were conducted to illustrate the algorithm. 展开更多
关键词 multi-state reliability series-parallel system load dependent failure rate common bus performance sharing
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Electric Loading Simulation System for Missile Wings and Rudders 被引量:1
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作者 齐蓉 林辉 陈明 《Defence Technology(防务技术)》 SCIE EI CAS 2006年第1期47-52,共6页
The design and the realization of missile wings and rudders loading simulation system based on digital signal processor (DSP) TMS320LF2407 and direct torque control (DTC) servo driver ACS600 are discussed. The structu... The design and the realization of missile wings and rudders loading simulation system based on digital signal processor (DSP) TMS320LF2407 and direct torque control (DTC) servo driver ACS600 are discussed. The structure and opration principle for the system are presented. Speediness and elimination of superabundant torque are two key difficulties for electric loading simulation system. The method which can eliminate the superabundant torque is researched. Test results show the airflow resistance when missile wings and rudders are spreading can be rapidly simulated with high accuracy. 展开更多
关键词 导弹 转矩 装载模拟系统 装载控制器
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An automatic loading system for rock core testing with an industrial CT scanner 被引量:3
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作者 Zhao Hong Zhao Yixin 《Petroleum Science》 SCIE CAS CSCD 2011年第4期490-493,共4页
A new type of a loading and measuring system was developed for testing failure and deformation of rock core samples with an industrial CT (ICT) scanner.The loading and measuring system consisted of a loading system ... A new type of a loading and measuring system was developed for testing failure and deformation of rock core samples with an industrial CT (ICT) scanner.The loading and measuring system consisted of a loading system and a computer control system.The maximum servo-controlled force was 2 tonnes.The new system was a high-stiffness system with a small size.During ICT tests,rock core samples could be easily loaded in the axial direction.So the initiation,propagation,and coalescence of cracks in core samples were observed on ICT images. 展开更多
关键词 Industrial CT dynamic loading automatic loading system rock core crack propagation
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Energy-Efficient Operation of Water Systems through Optimization of Load Power Reduction in Electricity Markets 被引量:1
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作者 Chouaib Mkireb Abel Dembele +1 位作者 Antoine Jouglet Thierry Denoeux 《Journal of Electronic Science and Technology》 CAS CSCD 2018年第4期304-315,共12页
Demand response(DR) is gaining more and more importance in the architecture of power systems in a context of flexible loads and high share of intermittent generation. Changes in electricity markets regulation in sever... Demand response(DR) is gaining more and more importance in the architecture of power systems in a context of flexible loads and high share of intermittent generation. Changes in electricity markets regulation in several countries have recently enabled an effective integration of DR mechanisms in power systems. Through its flexible components(pumps, tanks), drinking water systems are suitable candidates for energy-efficient DR mechanisms. However, these systems are often managed independently of power system operation for both economic and operational reasons. Indeed, a sufficient level of economic viability and water demands risk management are necessary for water utilities to integrate their flexibilities to power system operation. In this paper,we proposed a mathematical model for optimizing pump schedules in water systems while trading DR blocs in a spot power market during peak times. Uncertainties about water demands were considered in the mathematical model allowing to propose power reductions covering the potential risk of real-time water demand forecasting inaccuracy.Numerical results were discussed on a real water system in France, demonstrating both economic and ecological benefits. 展开更多
关键词 Demand response(DR) drinking water systems peak energy load power system operation spot power market
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Investigation of rotor control system loads 被引量:3
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作者 Sun Tao Tan Jianfeng Wang Haowen 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第5期1114-1124,共11页
This paper concentrates on the aeroelasticity analysis of rotor blade and rotor control systems. A new multi-body dynamics model is established to predict both rotor pitch link loads and swashplate servo loads. Two he... This paper concentrates on the aeroelasticity analysis of rotor blade and rotor control systems. A new multi-body dynamics model is established to predict both rotor pitch link loads and swashplate servo loads. Two helicopter rotors of UH-60A and SA349/2, both operating in two critical flight conditions, high-speed flight and high-thrust flight, are studied. The analysis shows good agreements with the flight test data and the calculation results using CAMRAD II. The mechanisms of rotor control loads are then analyzed in details based on the present predictions and the flight test data. In high-speed conditions, the pitch link loads are dominated by the integral of blade pitching moments, which are generated by cyclic pitch control. In high-thrust conditions, the positive pitching loads in the advancing side are caused by high collective pitch angle, and dynamic stall in the retreating side excites high-frequency responses. The swashplate servo loads are predominated by the rotor pitch link loads, and the inertia of the swashplate has significant effects on high-frequency harmonics of the servo loads. 展开更多
关键词 Comprehensive aeroelasticity analysis Control systems Helicopter rotors loads Multi-body dynamic model
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Multi-Channel Force Control System for Static Loading
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作者 陈彩可 王军政 +1 位作者 马立玲 李金仓 《Journal of Beijing Institute of Technology》 EI CAS 2003年第S1期1-6,共6页
An eight-channel force loading system is presented, which adopts position control system and force control system switching model, small flow servo valve controlled capacious cylinder system scheme, intelligent PID al... An eight-channel force loading system is presented, which adopts position control system and force control system switching model, small flow servo valve controlled capacious cylinder system scheme, intelligent PID algorithm and distributed load approach. Through the analyses of the equivalent model of valve controlled cylinder force subsystem, a controller based on intelligent PID algorithm is designed, which is not sensitive to the variation of parameters such as environmental stiffness. According to the coupling of multiple load channels, a distributed load approach is employed in the superior monitor computer. Experimental results show that the system designed has high precision and robustness. 展开更多
关键词 electro-hydraulic servo loading system static force loading force control
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Bearing loads of dual rotor-bearing system under stationary and transient conditions
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作者 刘树辉 王国丽 +2 位作者 朱清乐 周年发 陈勇 《Journal of Beijing Institute of Technology》 EI CAS 2012年第4期460-465,共6页
Aimed at aeroengine vibration failure, bearing loads of dual rotor-bearing system caused by unbalance are calculated under stationary and transient conditions. The three-dimensional (3-D) finite element method (FEM... Aimed at aeroengine vibration failure, bearing loads of dual rotor-bearing system caused by unbalance are calculated under stationary and transient conditions. The three-dimensional (3-D) finite element method (FEM) model of dual rotor-bearing system was established. Applying the ro- tor dynamics function of Ansys 12.0, bearing loads were calculated under various unbalance force in stationary condition, and the transient vibration characteristics and the effect of acceleration on bearing loads were discussed. On the basis of simulation results, the influence disciplines of unbal- ance on bearing loads and theoretic reference for reducing bearing loads during start-up were ob- tained. 展开更多
关键词 dual rotor-bearing system bearing loads rotor dynamics AEROENGINE
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Power System Aggregate Load Area Modelling by Particle Swarm Optimization 被引量:1
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作者 Jian-Lin Wei, Ji-Hong Wang, Q. H. Wu, Nan Lu Department of Electrical Engineering and Electronics, University of Liverpool, Brownlow Hill, Liverpool L69 3GJ, UK 《International Journal of Automation and computing》 EI 2005年第2期171-178,共8页
This paper presents a new approach for deriving a power system aggregate load area model (ALAM). In this approach, an equivalent area load model is derived to represent the load characters for a particular area load o... This paper presents a new approach for deriving a power system aggregate load area model (ALAM). In this approach, an equivalent area load model is derived to represent the load characters for a particular area load of a power system network. The Particle Swarm Optimization (PSO) method is employed to identify the unknown parameters of the generalised system, ALAM, based on the system measurement directly using a one-step scheme. Simulation studies are carried out for an IEEE 14-Bus power system and an IEEE 57-Bus power system. Simulation results show that the ALAM can represent the area load characters accurately under different operational conditions and at different power system states. 展开更多
关键词 load modelling power system particle swarm optimization parameter identificaiotn
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ELECTRO-HYDRAULIC COMPOUND CONTROL METHOD AND CHARACTERISTIC OF CONTROL FOR TENSION SYSTEM WITH HIGH INERTIA LOADS 被引量:2
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作者 ZHONG Tianyu WANG Qingfeng +1 位作者 LI Yanmin GONG Fangyou 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第3期391-395,共5页
Based on the pressure regulation circuit adopting electro-hydraulic proportional relief valve to control tension, a new type of electro-hydraulic compound control circuit with throttle control unit is presented, which... Based on the pressure regulation circuit adopting electro-hydraulic proportional relief valve to control tension, a new type of electro-hydraulic compound control circuit with throttle control unit is presented, which can obtain optimal dynamic damping ratio through real-time altering pressure-flow gain of the throttle control unit, improve the dynamic characteristic of tension follow-up control for the tension system with high inertia loads. Moreover, the characteristic when the cable linear velocity variation causes change of tension is investigated, and a compound control strategy is proposed. The theoretical analysis and experimental results show that the electro-hydraulic compound control circuit is effective and the characteristic of the compound control strategy is satisfactory. 展开更多
关键词 High inertia loads Tension control system Compound control strategy
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Application of subsurface wastewater infiltration system to on-site treatment of domestic sewage under high hydraulic loading rate 被引量:7
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作者 Ying-hua Li Hai-bo Li +2 位作者 Xin-yang Xu Xuan Gong Yong-chun Zhou 《Water Science and Engineering》 EI CAS CSCD 2015年第1期49-54,共6页
In order to enhance the hydraulic loading rate (HLR) of a subsurface wastewater infiltration system (SWIS) used in treating domestic sewage, the intermittent operation mode was employed in the SWIS. The results sh... In order to enhance the hydraulic loading rate (HLR) of a subsurface wastewater infiltration system (SWIS) used in treating domestic sewage, the intermittent operation mode was employed in the SWIS. The results show that the intermittent operation mode contributes to the improvement of the HLR and the pollutant removal rate. When the wetting-drying ratio (RwD) was 1.0, the pollutant removal rate increased by (13.6 ± 0.3)% for NH3-N, (20.7 ± 1.1)% for TN, (18.6± 0.4)% for TP, (12.2 ± 0.5)% for BOD, (10.1 ± 0.3)% for COD, and (36.2 ± 1.2)% for SS, compared with pollutant removal rates under the continuous operation mode. The pollutant removal rate declined with the increase of the HLR. The effluent quality met The Reuse of Urban Recycling Water - Water Quality Standard for Scenic Environment Use (GB/T 18921-2002) even when the HLR was as high as 10 cm/d. Hydraulic conductivity, oxidation reduction potential (ORP), the quantity of nitrifying bacteria, and the pollutant removal rate of NH3-N increased with the decrease of the RWD. For the pollutant removal rates of TP, BOD, and COD, there were no significant difference (p 〈 0.05) under different RwDS. The suggested RWD was 1.0. Relative contribution of the pretreatment and SWlS to the pollutant removal was examined, and more than 80% removal of NH3-N, TN, TP, COD, and BOD occurred in the SWIS. 展开更多
关键词 Domestic sewage Subsurface wastewater infiltration system Intermittent operation mode Hydraulic loading rate Pollutant removal rate
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Load-Balance Policy in Two Level-Cluster File System
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作者 LIU Yuling SONG Weiwei MA Xiaoxue 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1935-1938,共4页
In this paper, we explored a load-balancing algorithm in a cluster file system contains two levels of metadata-server, primary-level server quickly distributestasks to second-level servers depending on the closest loa... In this paper, we explored a load-balancing algorithm in a cluster file system contains two levels of metadata-server, primary-level server quickly distributestasks to second-level servers depending on the closest load-balancing information. At the same time, we explored a method which accurately reflect I/O traffic and storage of storage-node: computing the heat-value of file, according to which we realized a more logical storage allocation. According to the experiment result, we conclude that this new algorithm shortens the executing time of tasks and improves the system performance compared with other load algorithm. 展开更多
关键词 cluster file system metadata-server load-BALANCING value of heat
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Computer analysis and evaluation of the training load system build
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作者 Guo KeLei 《Journal of Zhouyi Research》 2014年第3期13-14,共2页
关键词 计算机分析 负荷系统 训练系统 综合评价 计算机集成管理 逻辑分析法 文献资料 网络技术
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Effect of Hydraulic Loading Rate on the Efficiency of Effluent Treatment in a Recirculating Puffer Aquaculture System Coupled with Constructed Wetlands 被引量:3
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作者 XU Jiabo SHI Yonghai +2 位作者 ZHANG Genyu LIU Jianzhong ZHU Yazhu 《Journal of Ocean University of China》 SCIE CAS 2014年第1期146-152,共7页
Constructed wetlands(CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer(Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate(HLR) on the efficiency of eff... Constructed wetlands(CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer(Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate(HLR) on the efficiency of effluent treatment by CWs was examined for over a month. The CWs were operated under brackish conditions(salinity 7.4–7.6) at 3 different HLRs(0.762, 0.633, and 0.458 m d–1) 3 times, 10 days each. Overall, the CWs exhibited high efficiency in removal of total ammonium nitrogen(by 81.03–92.81%) and nitrite nitrogen(by 99.40%–99.68%). The efficiency of CWs in removal of total ammonium nitrogen, nitrate nitrogen, total Kjeldahl nitrogen, total phosphorous, and total suspended solids(TSS) increased with the decrease of HLR. The CWs operated at the 3 HLRs in a decreasing trend proves to be effective, providing a useful method for effluent treatment in commercial puffer aquaculture systems. 展开更多
关键词 CONSTRUCTED WETLAND recirculating AQUACULTURE system PUFFER AQUACULTURE BRACKISH water hydraulic loading rate
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A model test system with a dynamic load device for geotechnical engineering in cold regions
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作者 ShuPing Zhao Wei Ma +1 位作者 GuiDe Jiao Fei Luo 《Research in Cold and Arid Regions》 2012年第2期115-120,共6页
A model test system with a dynamic load device for geotechnical engineering in cold regions is presented. This system consists of a model test tank, a refrigeration device and temperature controller, a dynamic load de... A model test system with a dynamic load device for geotechnical engineering in cold regions is presented. This system consists of a model test tank, a refrigeration device and temperature controller, a dynamic load device, together with sensors and data loggers for detecting stress, deformation, and temperature changes. The system can accommodate soil blocks up to 3 m in length, 2.5 m in width, and 1 m in height. The lowest temperature provided by the refrigeration device is -20 ℃. The maximum load provided by the dynamic load device is 100 kN and the vibration fi'equency of the dynamic load can range from 0.1 to 10 Hz. A number of waveforms, such as sine waves, rectangular waves, triangle waves, and other user-defined waves can be generated by the dynamic load device controller. 展开更多
关键词 model test system dynamic load device STRESS DEFORMATION temperature change
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Method for acquiring part load distribution coefficient of air conditioning system
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作者 丁勇 李百战 谭颖 《Journal of Central South University》 SCIE EI CAS 2009年第S1期95-99,共5页
This paper presents a method to acquire runtime distribution ratio of building air conditioning system under part load condition (part load coefficient of system) through practical energy consumption data. By utilizin... This paper presents a method to acquire runtime distribution ratio of building air conditioning system under part load condition (part load coefficient of system) through practical energy consumption data. By utilizing monthly energy consumption data of the entire year as the analysis object,this paper identifies data distribution,verifies distribution characteristics and analyzes distribution probability density for the issue of running time distribution ratio of air conditioning system in part load zones in the whole operation period,thus providing a basic calculation basis for an overall analysis of energy efficiency of air conditioning system. In view of the general survey of public building energy consumption carried by the government of Chongqing,this paper takes the governmental office building as an example,the part load ratio coefficient corresponding to practical running of air conditioning system of governmental office building in Chongqing is obtained by utilizing the above probability analysis and the solving method of probability density function. By utilizing the ratio coefficient obtained using this method,the part load coefficient with any running ratio of air conditioning system can be obtained according to the requirement of analysis,which can be used in any load ratio for analyzing running energy efficiency of air conditioning system. 展开更多
关键词 air CONDITIONING system MONTHLY energy CONSUMPTION PROBABILITY density distribution part load COEFFICIENT of system
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Effect of Load Power Factor on Electromechanical Wave Propagation in Ring Power System
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作者 MOHAMMED Heikal 《Computer Aided Drafting,Design and Manufacturing》 2008年第2期109-112,共4页
One-dimensional ring power system is discredited to a number of nodes each containing a generator with internal reactance and load branch of resistance and reactance with a certain power factor. When a disturbance occ... One-dimensional ring power system is discredited to a number of nodes each containing a generator with internal reactance and load branch of resistance and reactance with a certain power factor. When a disturbance occurs at any machine in the power system, simulative analysis is performed to verify how the variation of load power factor affecting the behavior of electromechanical wave propagation by using the MATLAB package, from which different situations are presented and discussed. These results show the type of load has no effect on the behavior of electromechanical wave propagation. 展开更多
关键词 electromechanical wave propagation one-dimensional power system continuum system load power factor MATLAB
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