• Title, Summary, Keyword: electric machine

Search Result 763, Processing Time 0.037 seconds

A Novel Stator Hybrid Excited Doubly Salient Permanent Magnet Brushless Machine for Electric Vehicles

  • Zhu Xiaoyong;Cheng Ming
    • Journal of Electrical Engineering and Technology
    • /
    • v.1 no.2
    • /
    • pp.185-191
    • /
    • 2006
  • In this paper, a novel stator hybrid excited doubly salient permanent magnet (SHEDS-PM) brushless machine with a special magnetic bridge is proposed for the first time. The originality of this machine is purposely to add a magnetic bridge in shunt with each PM pole, which not only maintains the stator lamination in its entireness, but also amplifies the effect of DC field flux on PM flux. An equivalent magnetic circuit is presented to clarify the novelty. Based on the 2-D finite element analysis, the static characteristics of the SHEDS-PM machine, namely phase flux linkage, back-EMF, cogging torque, winding inductance and static torque are deduced. The corresponding results on a prototype machine illustrate that the proposed machine is promising for application to electric vehicles.

A Study on the Selections of Optimized Process Conditions in the Wire Electric Discharge (와이어방전 가공시 최적 가공조건 선정에 관한 연구)

  • 김선진;성백섭;목포대;정성택;반재삼;조규재
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • /
    • pp.631-636
    • /
    • 2002
  • The purpose of this study was to present the method to choose the optimization machining condition for the wire electric machine. This was completed by examining the ever- changing quality of the material and by improving the function of the wire electric discharge machine. Precision metal mold products and the unmanned wire electric discharge machining system were used and then applied in industrial fields. This experiment uses the wire electric discharge machine with brass wire electrode of 0.25mm. To measure the precision of the machining surface, average values are obtained from 3 samples of measures of center-line average roughness by using a third dimension gauge and a stylus surface roughness gauge. In this experiment, we changed no-node voltage to 7 and 9, pulse-on-time to $6\mu\textrm{s}$, $8\mu\textrm{s}$ and $10\mu\textrm{s}$, pulse-off-time to $8\mu\textrm{s}$, $10\mu\textrm{s}$ and $13\mu\textrm{s}$, and experimented on wire tension at room temperature by 1000gf, 1200gf, and 1400gf, respectively

  • PDF

A study for its Characteristics with Electric Variation in an Electrical Discharge Machining (방전가공에서 전기적 변화가 갖는 방전 특성에 관한 연구)

  • 신근하
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • /
    • pp.132-136
    • /
    • 1996
  • A Study is a experiment which is figure out to aptimum discharge cutting condition of the surfaceroughness, electric discharging speed and electro wear ratio with Ton Toff and V(voltage) as an input condition according to the current(Ip) in an electric spark machine ; 1)Electrode is utilized Cu(coper) and Graphite. 2)Work piece is used the material of carbon steel. The condition of experiment is; 1)Current is varied 0.7(A) to 50(A). 2)Pulse time(Ton) is varied 3($\mu$s) to 240($\mu$s) and also Toff is varied 7($\mu$s) to 20($\mu$s). 3)The time of electric discharging to work piece in each time is 30(min) to 60(min) 4)After the upper side of work piece was measured in radius (5${\mu}{\textrm}{m}$) of syulus analyzed the surface roughness to made the table and graph of Rmax by yielding data. 5)Electro wear ratio is; \circled1Coper was measured cx-machining and post machining but the electronic baiance. \circled2The ex-machining of graphite measured by it, the post-machining was found the data from volume specific gravity and analyzed to made its table and graph on ground the data 6)In order to keep the accuracy of voltage affected to the work piece was equipped with the A.V.R(Automatic Voltage Regulator). 7)The memory scope was sticked to the electric spark machine. 8)In order to preserve the precision of current, to get rid of the noise occured by internal resistance of electric spark machine and to force injecting for the discharge fluid, it made the fixed table for a work piece to minimize the work error by means of one's failure during the electric discharging According to above results, the surface roughness by the variation of electrodw and current was analyzed to compare KS(Korea Standards) It was decided the optimum condition of electric discharge cutting through analyzing the effect of electric discharge speed and electro wear ratio.

  • PDF

A Study on the Dropping Shock of Household Electric Appliances during Materials Handling (가전제품의 하역 중 낙하충격에 관한 연구)

  • Lee, Soo-Keun
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.6 no.1
    • /
    • pp.37-40
    • /
    • 2000
  • This study was carried out to investigate dropping shock of household electric appliances during materials handling. Microwave oven($18{\ell}$), TV(16") and washing machine(6.2kg) were singled out as the study items. From the results of dropping test by KS A 1026(General Rules of Performance Testing for Packaged Freights), relative equations were gained as follow : y=0.0863x+10.032 for microwave oven, y=0.136x+7.85 for TV and y=0.214x+5.8 for washing machine (where y is G-factor and x is Dropping height). The maximum values of dropping shock during materials handling were measured to be $11{\sim}14G$ for microwave oven, $12{\sim}15G$ for TV and $10{\sim}12G$ for washing machine. The maximum shocks of microwave oven, TV and washing machine during materials handling were corresponding to dropping shocks of dropping height 45.98cm, 52.57cm and 28.97cm by KS A 1026.

  • PDF

Influencing factors and prediction of carbon dioxide emissions using factor analysis and optimized least squares support vector machine

  • Wei, Siwei;Wang, Ting;Li, Yanbin
    • Environmental Engineering Research
    • /
    • v.22 no.2
    • /
    • pp.175-185
    • /
    • 2017
  • As the energy and environmental problems are increasingly severe, researches about carbon dioxide emissions has aroused widespread concern. The accurate prediction of carbon dioxide emissions is essential for carbon emissions controlling. In this paper, we analyze the relationship between carbon dioxide emissions and influencing factors in a comprehensive way through correlation analysis and regression analysis, achieving the effective screening of key factors from 16 preliminary selected factors including GDP, total population, total energy consumption, power generation, steel production coal consumption, private owned automobile quantity, etc. Then fruit fly algorithm is used to optimize the parameters of least squares support vector machine. And the optimized model is used for prediction, overcoming the blindness of parameter selection in least squares support vector machine and maximizing the training speed and global searching ability accordingly. The results show that the prediction accuracy of carbon dioxide emissions is improved effectively. Besides, we conclude economic and environmental policy implications on the basis of analysis and calculation.

Analysis of Mechanical Fixation Made of Aluminum Alloy in an Axial Flux Permanent Magnet Machine

  • Lee, Jiyoung;Park, Byounggung;Koo, Daehyun
    • Journal of Magnetics
    • /
    • v.19 no.3
    • /
    • pp.309-313
    • /
    • 2014
  • This paper presents an eddy current loss analysis of a Mechanical Fixation (MF) made of 6061 aluminum alloy, which is used for an NS type double-rotor single-stator axial flux permanent magnet machine. The prototype MF made of aluminum alloy shows good mechanical performance, but poor electro-magnetic performance, since the machine's efficiency can decrease because of eddy current loss in the MF. In order to prevent efficiency decrease, a modification of the MF structure is also introduced. Three-dimensional finite element analysis (FEA) is used for magnetic field analysis, and eddy current losses are computed. The analysis results are compared to, and verified by the test results.

Characteristics of AC Treeing for Three Epoxy Resins for High Voltage Heavy Electric Machine Appliances (고전압 중전기기용 에폭시 수지 3종에 대한 교류트리잉 파괴특성)

  • Park, Jae-Jun
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.67 no.10
    • /
    • pp.1322-1329
    • /
    • 2018
  • In this paper, the reliability test of three kinds of epoxy resin for GIS Spacer, which is a high voltage based heavy electric machine, AC electrical treeing experiments were performed. Three types of epoxy resins, Araldite B41, CT 5531 CI and B46, have slight viscosity differences. An non-uniform electric field, E = 1149.4 kV/mm, as the needle to plate electrode, a power source with a frequency of 1 kHz was applied to the tree electrode for accelerated deterioration. The treeing phenomena of the three kinds of epoxy resin all initiated, propagated, and destroyed by the branch tree. Epoxy Resin B46 was 145 times longer than B41 and 53 times longer than CT 5531CI. I think that the choice of epoxy resin is very important in choosing high voltage heavy electric machine insulation materials.

Analysis of Torque Characteristic Considering The Dimensional Tolerance of BLDC Motor (치수공차를 고려한 BLDC 전동기의 토크 특성 해석)

  • Kim, Young-Kyoun;Hong, Jung-Pyo;Hur, Jin;Sung, Ha-Kyong
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.750-752
    • /
    • 2003
  • This paper presents a method of tolerance analysis for a electric machine. Tolerance analysis technique is required to find the tolerance band of design variables and estimate the characteristic distribution of the electric machine, because that manufacturing tolerances as well as measuring errors have a great influence on the electric machine. Therefore, this paper introduces Stochastic Response Surface Methodology to achieve the tolerance analysis. As an example, the tolerance analysis is applied to the analysis of torque characteristics for a BLDC motor from the electric point of view.

  • PDF

Comparative Study of Stator Core Composition in Transverse Flux Rotary Machine

  • Lee, Ji-Young;Moon, Seung-Ryul;Koo, Dae-Hyun;Kang, Do-Hyun;Lee, Geun-Ho;Hong, Jung-Pyo
    • Journal of Electrical Engineering and Technology
    • /
    • v.6 no.3
    • /
    • pp.350-355
    • /
    • 2011
  • This paper deals with the comparison of magnetic characteristics in transverse flux rotary machine according to different stator core composition with the same rotor. Three different stator designs are considered in the analysis according to the material composition of inner and outer stator cores. Electromotive force (EMF), inductance, torque, and core losses are calculated by threedimensional finite element analysis. Calculated and measured results of back-EMF according to the analysis models in dependency on speed are presented.

Analytical Calculation for Predicting the Air Gap Flux Density in Surface-Mounted Permanent Magnet Synchronous Machine

  • Feng, Yan-li;Zhang, Cheng-ning
    • Journal of Electrical Engineering and Technology
    • /
    • v.12 no.2
    • /
    • pp.769-777
    • /
    • 2017
  • The research of air gap flux density has a significant effect on predicting and optimizing the structure parameters of electrical machines. In the paper, the air gap coefficient, leakage flux factor and saturation coefficient are first analytically expressed in terms of motor properties and structure parameters. Subsequently, the analytical model of average air gap flux density for surface-mounted permanent magnet synchronous machines is proposed with considering slotting effect and saturation. In order to verify the accuracy of the proposed analytical model, the experiment and finite element analysis (FEA) are used. It shows that the analytical results keep consistency well with the experimental result and FEA results, and the errors between FEA results and analytical results are less than 5% for SPM with high power. Finally, the analytical model is applied to optimizing the motor structure parameters. The optimal results indicate that the analytical calculation model provides a great potential to the machine design and optimization.