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Optimal Placement and Sizing of Distributed Generations for Power Losses Minimization Using PSO-Based Deep Learning Techniques
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作者 Bello-Pierre Ngoussandou Nicodem Nisso +1 位作者 Dieudonné Kaoga Kidmo   Kitmo 《Smart Grid and Renewable Energy》 2023年第9期169-181,共13页
The integration of distributed generations (DGs) into distribution systems (DSs) is increasingly becoming a solution for compensating for isolated local energy systems (ILESs). Additionally, distributed generations ar... The integration of distributed generations (DGs) into distribution systems (DSs) is increasingly becoming a solution for compensating for isolated local energy systems (ILESs). Additionally, distributed generations are used for self-consumption with excess energy injected into centralized grids (CGs). However, the improper sizing of renewable energy systems (RESs) exposes the entire system to power losses. This work presents an optimization of a system consisting of distributed generations. Firstly, PSO algorithms evaluate the size of the entire system on the IEEE bus 14 test standard. Secondly, the size of the system is allocated using improved Particles Swarm Optimization (IPSO). The convergence speed of the objective function enables a conjecture to be made about the robustness of the proposed system. The power and voltage profile on the IEEE 14-bus standard displays a decrease in power losses and an appropriate response to energy demands (EDs), validating the proposed method. 展开更多
关键词 Distributed Generations Deep Learning Techniques Improved Particle Swarm Optimization power losses power losses Minimization Optimal Placement
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Minimization of Electric Power Losses on 132 kV and 220 kV Uganda Electricity Transmission Lines
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作者 Ounyesiga Living Stephen Ndubuisi Nnamchi +2 位作者 Kelechi John Ukagwu Abubakar Abdulkarim Zaid Oluwadurotimi Jagun 《Energy and Power Engineering》 CAS 2023年第2期127-150,共24页
The classical minimization of power losses in transmission lines is dominated by artificial intelligence techniques, which do not guarantee global optimum amidst local minima. Revolutionary and evolutionary techniques... The classical minimization of power losses in transmission lines is dominated by artificial intelligence techniques, which do not guarantee global optimum amidst local minima. Revolutionary and evolutionary techniques are encumbered with sophisticated transformations, which weaken the techniques. Power loss minimization is crucial to the efficient design and operation of power transmission lines. Minimization of losses is one way to meet steady grid supply, especially at peak demand. Thus, this paper has presented a gradient technique to obtain optimal variables and values from the power loss model, which efficiently minimizes power losses by modifying the traditional power loss model that combines Ohm and Corona losses. Optimality tests showed that the unmodified model does not support the minimization of power losses on transmission lines as the Hessian matrix portrayed the maximization of power losses. However, the modified model is consistent with the gradient method of optimization, which yielded optimum variables and values from the power loss model developed in this study. The unmodified (modified) models for Bujagali-Kawanda 220 kV and Masaka West-Mbarara North 132 kV transmission lines in Uganda showed maximum power losses of 0.406 (0.391) and 0.452 (0.446) kW/km/phase respectively. These results indicate that the modified model is superior to the unmodified model in minimizing power losses in the transmission lines and should be implemented for the efficient design and operation of power transmission lines within and outside Uganda for the same transmission voltages. 展开更多
关键词 MINIMIZATION power losses Transmission Lines Corona and Ohms losses Transmission Model
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Effects of Dimensional Tolerances on the Friction Power Loss of Hydrodynamic Journal Bearing System 被引量:2
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作者 魏塬 陈照波 +1 位作者 焦映厚 徐武彬 《Journal of Donghua University(English Edition)》 EI CAS 2014年第3期266-271,共6页
According to the dimensional tolerances on hydrodynamic journal bearing system, a nonlinear oil film force model was established,and the Reynolds' equation was solved by adopting finite difference method. In order... According to the dimensional tolerances on hydrodynamic journal bearing system, a nonlinear oil film force model was established,and the Reynolds' equation was solved by adopting finite difference method. In order to fulfill different dimensional tolerances in the system,adopting 2kfactor design and using the eccentricity ratio corresponding to the stability critical curve,the effects of the friction power loss brought by the dimensional tolerances of the dynamic viscosity,bearing width,bearing diameter and journal diameter were analyzed. The effect on dynamic characteristics of the hydrodynamic journal bearing system was quantitatively analyzed,and the nonlinear dynamic analysis, modeling and calculation methods were studied while considering the manufacturing tolerances. The results show that in contrast to the impacts of the tolerances in journal diameter,dynamic viscosity and bearing width,the bearing diameter tolerance would lead to the rise in the power loss, and the dimensional tolerances have different degrees of impacts on the journal bearing system. The friction power loss decreased as the eccentricity ratio increased, and when the eccentricity ratio was 0. 695 the power loss came to the minimum.The investigation would find the best solution and reduce energy consumption,then control varieties of nonlinear dynamical behavior effectively,and provide a theoretical basis for hydrodynamic journal bearing system in parameter design. 展开更多
关键词 hydrodynamic journal bearing dimensional tolerances factor design friction power loss
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Effect of V2O5-CaCO3-Nb2O5 Contents on Properties of Low Power Loss Mn-Zn Ferrites 被引量:1
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作者 宋晓敏 龚小燕 +2 位作者 李纲 彭声谦 邵峰 《Journal of Shanghai University(English Edition)》 CAS 2005年第6期561-564,共4页
Effect of the content of dopants in the manganese-zinc ferrites on the low power loss is studied by measuring magnetic properties and observing the grain boundary structures. The Mn0.738Zn0.206Fe2.066O4 composition po... Effect of the content of dopants in the manganese-zinc ferrites on the low power loss is studied by measuring magnetic properties and observing the grain boundary structures. The Mn0.738Zn0.206Fe2.066O4 composition powders were prepared by using conventional ceramic powder processing technique. The microstructure of grain boundary was observed by scanning electron microscope (SEM). It has been found that power loss is greatly dependent upon the content of the additives. 展开更多
关键词 Mn-Zn ferrites power loss magnetic properties.
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General Properties of Low-frequency Power Losses in Fe-based Nanocrystalline Soft Magnetic Alloys 被引量:1
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作者 Yanzhong ZHANG, Huijuan JIN and Ying SHI (Shanghai Key Laboratory for Research and Developing and Applications of Metallic Function Materials, Research Center, Shanghai Iron and Steel Research institute,Shanghai 200940, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第1期37-44,共8页
The dependences of the power loss per cycle on frequency f and amplitude flux density Bm have been investigated for the three main original magnetic states in five sorts of Fe-based nanocrystalline soft magnetic alloy... The dependences of the power loss per cycle on frequency f and amplitude flux density Bm have been investigated for the three main original magnetic states in five sorts of Fe-based nanocrystalline soft magnetic alloys in the ranges of 10 Hz<=f<=1000 Hz and 0.4 T<= Bm <=1.0 T. The total loss P is decomposed into the sum of the hysteresis loss Physt, the classical eddy current loss Pel and the excess loss Pexc. Physt has been found to be proportional to Bm^2 and f. The behavior of Pexc/f vs f being equivalent to P/f vs f clearly exhibits nonlinearity in the range not more than about 120 Hz, whereas the behavior of P/f vs f roughly shows linearity in the range far above 100 Hz and not more than 1000 Hz. In the range up to 1000 Hz, Physt is dominant in the original high permeability state and the state of low residual flux density, whereas Pexc in the state of high residual flux density is dominant in the wider range above about 100 Hz. The framework of the statistical theory of power loss has been used for representing the behavior of Pexc/f vs f. It has been found that the number n of the simultaneously active 'Magnetic Objects' linearly varies as n = n0 + Hexc/H0 as a function of the dynamic field Hexc in the range below about 120 Hz, whereas n approximately follows a law of the form n = n0 + (Hexc/H0)^m with 1 < m < 2 in the range far above 100 Hz and not more than 1000 Hz. The values of the field HO in principle related to the microstructure and the domain structure have been calculated for the three states. 展开更多
关键词 General Properties of Low-frequency power losses in Fe-based Nanocrystalline Soft Magnetic Alloys FE
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Electrical Power Losses in a Photovoltaic Solar Cell Operating under Partial Shading Conditions 被引量:1
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作者 Abdouramani Dadjé Noel Djongyang Réné Tchinda 《Journal of Power and Energy Engineering》 2017年第10期19-33,共15页
The aim of this paper is to determine the power losses recorded by a PV generator operating under partial shading conditions. These losses are evaluated through two distinct methods. The first method is based on mathe... The aim of this paper is to determine the power losses recorded by a PV generator operating under partial shading conditions. These losses are evaluated through two distinct methods. The first method is based on mathematical modeling, while the second is based on Simulink’s physical model. The losses recorded are considerable and increase as a function of the increase in the percentage of shading up to a limit value where they become constant in the case where an ideal by-pass diode is connected in parallel with the modules. This limit value is non-existent in the case where the bypass diode is not ideal, which in fact corresponds to the real model. However, it emerges that the power losses are minimized in a PV system comprising bypass diodes, in particular in the case where the partial shading is considerable. 展开更多
关键词 Electrical power losses PV Generator Partial Shading Conditions Mathematical Modeling Simulink’s Physical Model
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Measurement of Radiated Power Loss on EAST
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作者 段艳敏 胡立群 +7 位作者 毛松涛 许平 陈开云 林士耀 钟国强 张继宗 张凌 王亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2011年第5期546-549,共4页
A type of silicon detector known as AXUV (absolute extreme ultraviolet) photodiodes is successfully used to measure the radiated power in EAST. The detector is characterized by compact structure, fast temporal respo... A type of silicon detector known as AXUV (absolute extreme ultraviolet) photodiodes is successfully used to measure the radiated power in EAST. The detector is characterized by compact structure, fast temporal response (〈0.5 s) and flat spectral sensitivity in the range from ultra-violet to X-ray. Two 16-channel AXUV arrays are installed in EAST to view the whole poloidal cross-section of plasma. Based on the diagnostic system, typical radiation distributions for both limiter and divertor plasma are obtained and compared. As divertor detachment occurs, the radiation distribution in X-point region is observed to vary distinctly. The total radiation power losses in discharges with different plasma parameters are briefly analyzed. 展开更多
关键词 radiated power loss AXUV photodiode EAST
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Voltage Profile Enhancement and Power Loss Reduction with Economic Feasibility Using Small Capacity Distribution Transformers
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作者 Rasool M.Imran Mohammed R.Saeed +5 位作者 Mohammed Amer Mohammed Osama A.Suhry Ihsan H.Abdulqadder Hasan Wahhab Salih Mohammed R.Almallah Firas M.F.Flaih 《Energy Engineering》 EI 2022年第6期2447-2467,共21页
Usually,rural areas can be electrified via three-phase distribution transformers with relatively large capacities.In such areas,low voltage lines are used for long distances,which cause power losses and voltage drop f... Usually,rural areas can be electrified via three-phase distribution transformers with relatively large capacities.In such areas,low voltage lines are used for long distances,which cause power losses and voltage drop for different types of consumers.Reducing losses and improving voltage profiles in rural distribution networks are significant challenges for electricity distribution companies.However different solutions were proposed in the literature to overcome these challenges,most of them face difficulties when applied in the conventional distribution network.To address the above issues,an applicable solution is proposed in this paper by installing a number of small-capacity distribution transformers instead of every single large-capacity transformer in rural areas.The proposed approach is implemented in the branch network of Al-Hoqool village,which belongs to the Nineveh distribution network.The network has been inspected on-site,drawn,and analyzed using the electrical systems analysis program(ETAP).The analysis showed that using the single-phase pole-mounted transformers can improve the voltage in the network’s end by 29%and enhance the voltage profile for all consumers.The analysis has also demonstrated that the modification can reduce the total power losses by 78%compared to the existing network.Concerning the economic aspect,the payback period for the proposed network is assigned to be 20 months. 展开更多
关键词 Single-phase pole-mounted transformer three-phase transformer power losses voltage profile distribution networks
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Deciphering the Origins of P1-Induced Power Losses in Cu(In_(x),Ga_(1–x))Se2(CIGS)Modules Through Hyperspectral Luminescence
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作者 César Omar Ramírez Quiroz Laura-Isabelle Dion-Bertrand +2 位作者 Christoph J.Brabec Joachim Müller Kay Orgassa 《Engineering》 SCIE EI 2020年第12期1395-1402,共8页
In this report,we show that hyperspectral high-resolution photoluminescence mapping is a powerful tool for the selection and optimiz1ation of the laser ablation processes used for the patterning interconnections of su... In this report,we show that hyperspectral high-resolution photoluminescence mapping is a powerful tool for the selection and optimiz1ation of the laser ablation processes used for the patterning interconnections of subcells on Cu(Inx,Ga1-x)Se2(CIGS)modules.In this way,we show that in-depth monitoring of material degradation in the vicinity of the ablation region and the identification of the underlying mechanisms can be accomplished.Specifically,by analyzing the standard P1 patterning line ablated before the CIGS deposition,we reveal an anomalous emission-quenching effect that follows the edge of the molybdenum groove underneath.We further rationalize the origins of this effect by comparing the topography of the P1 edge through a scanning electron microscope(SEM)cross-section,where a reduction of the photoemission cannot be explained by a thickness variation.We also investigate the laser-induced damage on P1 patterning lines performed after the deposition of CIGS.We then document,for the first time,the existence of a short-range damaged area,which is independent of the application of an optical aperture on the laser path.Our findings pave the way for a better understanding of P1-induced power losses and introduce new insights into the improvement of current strategies for industry-relevant module interconnection schemes. 展开更多
关键词 Cu(In_(x) Ga_(1-x))Se2 Cell-to-module efficiency gap P1-induced power losses Hyperspectral photoluminescence Laser ablation short-range heat effect
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Optimal Placement of Reclosers to Minimize Power Losses during Non-Load Bearing Disturbances in a Power Distribution Using Firefly Algorithm
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作者 Wyclife Odongo Amolo Peter Musau Abraham Nyete 《Journal of Power and Energy Engineering》 2021年第5期63-75,共13页
The research reported in this paper focuses on non-technical power loss reduction for power distribution systems. Such reduction of costs of energy not served (ENS.COST), is intelligently evaluated and optimized using... The research reported in this paper focuses on non-technical power loss reduction for power distribution systems. Such reduction of costs of energy not served (ENS.COST), is intelligently evaluated and optimized using a firefly algorithm, from where savings of 43.3% on energy not served are achieved. 展开更多
关键词 loss Minimization Non-Load Bearing power losses Optimum Location Reclosers Transient power Balance
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Diagnosis of Thermal Overload and Power Losses in Boat Yang 1’s CAT 3408 Marine Diesel Engine from Used Oil and Coolant Analysis
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作者 Maurice Vanlie Kontchou Théophile Emakoua Achille Njomoue Pandong 《Modern Mechanical Engineering》 CAS 2022年第3期74-82,共9页
In the design of the CAT 3408 engine, the Low Temperature (BT) circuits used to cool the engine lubricating oil and the charge air and the High Temperature (HT) circuits for cooling the cylinder liners, cylinder heads... In the design of the CAT 3408 engine, the Low Temperature (BT) circuits used to cool the engine lubricating oil and the charge air and the High Temperature (HT) circuits for cooling the cylinder liners, cylinder heads and body of turbofans are mainly used to cool the engine, so that it works properly. This work, based on the analysis carried out, to determine the lubrication compliance of the Yacco VX 100 - SAE 15 W-40 oil and that of the Camwater water used in the engine of the Boat Yang 1 by carrying out a series of conventional tests such as that: the density, the viscosity, the viscosity index, the flash point, the density, the sulphate center content, the water content, the total acidity index (TAN), total basic number (TBN) and pour point for the oil case and pH, hardness, sodium chloride content [NaCl], sodium sulphate content [NaSO<sub>4</sub>] for the water case which will be compared to the specified requirements to determine whether compliance is achieved for each of these characteristics. The results of the oil and water samples taken from the engine after use show that the used oil gives a specific gravity of 0.8822, a viscosity (at 40°C) of 92.29 mm<sup>2</sup>/s, a viscosity (at 100°C) of 13.99 mm<sup>2</sup>/s, a viscosity index (VI) of 155.39, a pour point -21°C, a Flash Point (VO) 215°C, a Sulfated ash content of 18%, a density 881.5 kg/m<sup>3</sup>, a total basic number (TBN) of 12.60 mgKOH/g, a Total Acid Index (TAN) of 3.096 mgKOH/g, a Water Content of 1.8 % and the water used gives a pH of 6.00, a hardness of 3.2 french degrees, a sodium chloride content [NaCl] of 0.468 mg/L, and a calcium sulphate content [CaSO<sub>4</sub>] of 2.38345 mg/L. the results of the water content and content of sulfated centers justify the thermal overload and power losses in the marine diesel engine CAT 3408 of the boat Yang 1 because of their values which are not in conformity with the standards. 展开更多
关键词 REPORTING REASONS Thermal Overload power losses
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Calculation of Skin Depths and Eddy-Current Power Losses for Magnetic Position Sensors
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作者 Chung-Ping Liu (Department of Electrical Engineering, Yuan Ze University, Chungli 320, Taiwan-China Yeong-Hwa Chang and Tsung-Kun Lin (Department of Electrical Engineering, Chung Cheng Institute of Technology, Taoyuan 335, Taiwan-China Kun-Tong Wu and Ch 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期244-245,共2页
We present a theoretic model to calculate skin depths and eddy-current power losses for a magnetic position sensor. Eddy-current, arised from the operation of an alternating-current excitation, induces secondary curre... We present a theoretic model to calculate skin depths and eddy-current power losses for a magnetic position sensor. Eddy-current, arised from the operation of an alternating-current excitation, induces secondary currents and fields between magnetic material and magnetic position sensor. In this paper, a magnetic position sensor system is simplified to be an outer-winding coil along the axial direction of a low carbon steel bar. The analytical model is derived from basic field and circuit theory considering a linear approximation for a nonlinear permeability. Thus the skin depths and eddy-current power losses from the model in eddy-current modeling techniques at various frequencies of an excited current source can be calculated. The proposed configuration is capable of predicting the skin depths and eddy-current power losses for a magnetic position sensor and has a consistence with experiments. 展开更多
关键词 Calculation of Skin Depths and Eddy-Current power losses for Magnetic Position Sensors
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Power losses caused by longitudinal HOMs in 1.3-GHz cryomodule of SHINE 被引量:2
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作者 Jun-Jie Guo Qiang Gu +2 位作者 Meng Zhang Zhen Wang Jian-Hao Tan 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第7期16-26,共11页
Shanghai high-repetition-rate XFEL and extreme light facility (SHINE), the first hard XFEL based on a superconducting accelerated structure in China, is now under development at the Shanghai Institute of Applied Physi... Shanghai high-repetition-rate XFEL and extreme light facility (SHINE), the first hard XFEL based on a superconducting accelerated structure in China, is now under development at the Shanghai Institute of Applied Physics, Chinese Academy of Sciences. In this paper, power losses caused by trapped longitudinal high-order modes (HOM), steady-state loss, and transient loss generated by untrapped HOMs in the 1.3-GHz SHINE cryomodule are investigated and calculated. The heat load generated by resistive wall wakefields is considered as well. Results are presented for power losses of every element in the 1.3-GHz cryomodule, caused by HOM excitation in the acceleration RF system of the continuouswave linac of SHINE. 展开更多
关键词 power loss HIGHER-ORDER MODES (HOMs) Resistive wall WAKEFIELDS Impedance SUPERCONDUCTING CAVITIES
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Improved Method of Power Loss and Electric Field Calculations of HVAC Transmission Lines
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作者 DU Zhiye RUAN Jiangjun JIN Shuo HUANG Guodong ZHU Lin 《高电压技术》 EI CAS CSCD 北大核心 2013年第10期2365-2371,共7页
An improved method for calculating the corona power loss and the ground-level electric field on HVAC transmission lines induced by corona is proposed.Based on a charge simulation method combined with a method of succe... An improved method for calculating the corona power loss and the ground-level electric field on HVAC transmission lines induced by corona is proposed.Based on a charge simulation method combined with a method of successive images,the proposed method has the number and location of the simulated charges not arbitrary.When the surface electric field of a conductor exceeds the onset value,charges are emitted from corona into the space around,and the space ions and the surface charges on each sub-conductor are simulated by using the images of the other sub-conductors.The displacements of the space ions are calculated at every time step during corona periods in both the positive and the negative half cycles.Several examples are calculated by using the proposed method,and the calculated electric field at the ground level and the corona power loss agree well with previous measurements.The results show that simulating 12 charges in each conductor during 600 time steps in one cycle takes less time while guarantees the accuracy.The corona discharge from a 220 kV transmission line enhances slightly(less than 2%) the electric field at the ground level,but this effect is little from a 500 kV line.The improved method is a good compromise between the time cost and the accuracy of calculation. 展开更多
关键词 位移计算 表面电场 功率损耗 输电线路 HVAC 模拟电荷法 500千伏线路 电晕放电
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Effects of Harmonics on Power Loss in XLPE Cables
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作者 W. Z. Gandhare K. D. Patil 《Energy and Power Engineering》 2013年第4期1235-1239,共5页
Harmonics in power systems is increasingly at high level. Also, there has been an incredible growth in the use of cross linked polyethylene (XLPE) cables in distribution systems. Harmonics cause additional power loss/... Harmonics in power systems is increasingly at high level. Also, there has been an incredible growth in the use of cross linked polyethylene (XLPE) cables in distribution systems. Harmonics cause additional power loss/temperature rise;causing premature failure of cables. Catastrophic failure of power cables leads to great inconvenience to consumers and loss of system reliability and money. To avoid the overheating of power cables;the additional power loss due to harmonics should be accurately calculated and properly accommodated by derating the cable. The present method of calculating the power loss in cables in harmonics rich environment is very arduous. The aim of this paper is to present the reasonably accurate method for evaluating effects of harmonics on the power loss in XLPE cables. Computational model is developed in MATLAB for power loss calculation using conventional method. Using this model, calculations are performed for aluminium and copper conductor XLPE cables of different size and type;for three different types of harmonics spectrums having total harmonics distortion (THD) of 30.68%, including all odd harmonics components up to 49th order. Using these results;a mathematical model in the form of simple empirical formula is developed by curve fitting technique. The results obtained by various models are presented and compared with error justification. 展开更多
关键词 Curve Fitting NON-SINUSOIDAL power loss Per Unit Harmonic Load QUADRATIC POLYNOMIAL Sinusoidal power loss
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Power Distribution Strategy Considering Active Power Loss for DFIGs Wind Farm
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作者 Xiao Du Yigong Zhang +3 位作者 Zhiqiang Dai Huan Liu Siming Wei Jin Liu 《Journal of Power and Energy Engineering》 2014年第4期213-219,共7页
With the development of concentrated wind power areas, new energy’s dispatching problems are more prominent with its fast expansion. However, we can maximize the utilization of wind power under power curtailment cond... With the development of concentrated wind power areas, new energy’s dispatching problems are more prominent with its fast expansion. However, we can maximize the utilization of wind power under power curtailment conditions by optimal wind power dispatching. The paper studies on the basic theories of wind power turbines, and analyses the power’s control and output characteristics of wind turbine, which analyses the double-fed inductor generator’s excellent decoupling control of power and its excellent reactive power output capability. By studying the characteristics of wind power output, this paper provides a strategy for optimal dispatch in wind power generation. The calculation results show that the total active and reactive power output of the wind farm match the request of dispatch center. And the total active loss and total reactive loss is the least in the meantime. 展开更多
关键词 WIND FARM power Distribution ACTIVE power loss
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Numerical Simulation of the Churning Power Losses in the Automotive Hypoid Gear Reducer
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作者 Lin Zou Mingya Du +2 位作者 Bing Jia Jinli Xu Liangshun Ren 《Journal of Applied Mathematics and Physics》 2018年第9期1951-1956,共6页
Improving vehicle transmission efficiency and reducing vehicle fuel consumption is currently one of the main objectives in the automotive field. Reducing gear churning power losses has significant influence on the dec... Improving vehicle transmission efficiency and reducing vehicle fuel consumption is currently one of the main objectives in the automotive field. Reducing gear churning power losses has significant influence on the decreasing vehicle fuel consumption. Based on the two phase flow theory, a 2D two-phase model of the simplified hypoid gear is established to predict the churning losses in different conditions, the VOF method is introduced to track the volume fraction of the free surface, a standard k-ε model is also built to calculate complex turbulence. The oil distributions at the different rotational speed, the different immersion depth and the different viscosity as well as the churning losses of the hypoid gear are obtained and discussed in detail. In general, the churning power losses increase with the increase of the speed, the immersion depth and the viscosity, while the rotational speed shows the greatest influence on the churning losses. It is hoped that this investigation will be helpful in automotive industry applications. 展开更多
关键词 CHURNING power loss Two PHASES Flow VOF Method Hypoid GEAR
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Simulation with Ideal Switch Models Combined with Measured Loss Data Provides a Good Estimate of Power Loss
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作者 Stig Munk-Nielsen Lucian N Tutelea Ulrik Jager 《电力电子技术》 CSCD 北大核心 2007年第8期107-110,共4页
Ideally,converter losses should be determined without using an excessive amount of simulation time.State-of-the-art power semiconductor models provide good accuracy,unfortunately they often require a very long simulat... Ideally,converter losses should be determined without using an excessive amount of simulation time.State-of-the-art power semiconductor models provide good accuracy,unfortunately they often require a very long simulation time.This paper describes how to estimate power losses from simulation using ideal switches combined with measured power loss data.The semiconductor behavior is put into a look-up table,which replaces the advanced semiconductor models and shortens the simulation time.To extract switching and conduction losses,a converter is simulated and the semiconductor power losses are estimated.Measurement results on a laboratory converter are compared with the estimated losses and a good agreement is shown.Using the ideal switch simulation and the post processing power estimation program,a ten to twenty fold increase in simulation speed is obtained,compared to simulations using advanced models of semiconductors. 展开更多
关键词 电力损耗 电力半导体器件 模拟 理想开关模型 估测
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A Study of Power Loss for 3 Phase Voltage Source Converter of Elevator
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作者 S.E.Cho S.J.Park 《科技信息》 2013年第3期255-257,共3页
In this paper,to study the power loss of converter for elevator,The analysis is to establish relationship between parameters(current,voltages and losses in the inverter and converter) relevant for sizing of major comp... In this paper,to study the power loss of converter for elevator,The analysis is to establish relationship between parameters(current,voltages and losses in the inverter and converter) relevant for sizing of major components of the drive was done.) For high PWM(pulse width modulation) frequency like in elevator applications of fpwm =10kHz,switching losses are dominant and are about 2/3 of the total losses on IGBT switch.Transition from continuous 3 phase to discontinuous 2 phase PWM results in 50% reduction of switching loses on IGBT devices providing that PWM is not done over 60deg angle in a particular phase when current has maximum value.Total losses on IGBT(conduction + switching) are reduced approximately by ~1/3 what is still a significant reduction.Two phase PWM with reduced losses can be used for applications when acoustic noise due to increased current ripple is not significant and fall back solution to regular 3 phase PWM when drive operates under rare extreme conditions resulting in increased heat sink temperature.The analysis will be examined by further laboratory testing simulating 60% duty cycle on a dynamometer. 展开更多
关键词 电梯 变换器 电流 散热片 脉冲宽度调制
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Distributed Generators Location and Capacity Effect on Voltage Profile Improvement and Power Losses Reduction Using Genetic Algorithm
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作者 Mohamad Fawzy Kotb 《Journal of Energy and Power Engineering》 2012年第3期446-455,共10页
关键词 遗传算法 电压档 发电机 分布式 电力损失 位置 有功功率损耗 容量
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