• Title/Summary/Keyword: Torque Optimization

Search Result 338, Processing Time 0.029 seconds

Optimal Design of Synchronous Reluctance Motor by Loss & Efficiency Evaluations Related to Slot Number using Response Surface Methodology (반응표면법을 이용한 슬롯수 관련 손실, 효율 평가애 따른 동기형 릴럭턴스 전동기의 최적 설계)

  • Park, Seong-June;Jang, Young-Jin;Lee, Jung-Ho
    • Proceedings of the KIEE Conference
    • /
    • 2004.10a
    • /
    • pp.123-125
    • /
    • 2004
  • This paper presents the application of response surface methodology (RSM) to design optimization for two types of synchronous reluctance motors (SynRMs); one has 12 slots with distributed winding, and the other has 6 slots with concentrated winding, to improve the ratio between torque ripple and average torque. The usefulness of RSM in optimization problem of SynRM is verified as compared with the results of finite element analysis. In the end, the optimized two SynRMs are compared with SynRM currently used in air-conditioning compressor in connection with torque performance and loss.

  • PDF

Optimal Design of Synchronous Reluctance Motor Related to Slot Number using Response Surface Methodology (반응표면방법론을 적용한 슬롯 수에 따른 동기형 릴럭턴스 전동기의 최적 설계)

  • Park, Seong-June;Lee, Jung-Ho
    • Proceedings of the KIEE Conference
    • /
    • 2005.04a
    • /
    • pp.117-119
    • /
    • 2005
  • This parer presents the application of response surface methodology (RSM) to design optimization for two types of synchronous reluctance motors (SynRMs) one has 12 slots with distributed winding, and the other has 6 slots with concentrated winding, to improve the ratio between torque ripple and average torque. The usefulness of RSM in optimization problem of SynRM is verified as compared with the results of finite element analysis. In the end, the optimized two SynRMs are compared with SynRM currently used in air-conditioning compressor in connection with torque performance and loss.

  • PDF

Core Shape Optimization for Cogging Torque Reduction of BLDC Motor (BLDC 모터의 코깅토크 저감을 위하 코어형상 최적화)

  • Han, Ki-Jin;Cho, Han-Sam;Cho, Dong-Hyeok;Cho, Hyun-Rae;Lee, Hae-Seok;Jung, Hyun-Kyo
    • Proceedings of the KIEE Conference
    • /
    • 1998.11a
    • /
    • pp.67-69
    • /
    • 1998
  • The cogging torque in the small BLDC motors used in the DVD driving system or HDD driving system can cause some serious vibration problem. In this paper, some core shapes that reduce cogging torque are found by using reluctance network method(RNM) for magnetic field analysis and genetic algorithm(GA) for optimization. The outer rotor type BLDC motor for the DVD ROM driving system has been optimized as an sample model.

  • PDF

A Study on the System Parameters to Reduce the Idle Gear Rattle (기어 래틀 저감을 위한 시스템 파라미터 연구)

  • 안병민;장일도;최은오;홍동표;정태진
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.6 no.3
    • /
    • pp.88-96
    • /
    • 1998
  • The rattle noise is the most significant in many kinds of manual gearbox nioses, which is generated at the idle stage of the engine operation. The main torsional vibrat- ion source of the driveline is the fluctuation of the engine torque. The gear rattle is impacts generating in the backlash of the free gear due to this torsional vibration. Many researchers reported the clutch torsional characteristic optimization method to reduce the idle gear rattle but only few of them give sufficient consideration to the system parameters like gear backlash, drag torque, system inertia, inertia distribution, engine torque fluctuation, idle engine rotation speed, and accessory load. In this paper, influence rate of system parameters on the gear rattle is presented and counterplans like backlash reduction, drag torque increase, inertia addition, inertia distribution modification and engine torque characteristic control are suggested.

  • PDF

Minimization of Cogging Torque in Permanent Magnet Motors by Stator Pole Shoe Pairing and Magnet Arc Design using Genetic Algorithm (유전자 알고리즘을 이용한 영구자석 모터의 고정자 잇날 페어링 및 자석 극호각 설계에 의한 코깅 토오크의 저감 설계)

  • Eom, Jae-Bu;Hwang, Geon-Yong;Hwang, Sang-Mun
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.51 no.1
    • /
    • pp.1-6
    • /
    • 2002
  • Cogging torque is often a principal source of vibration and acoustic noise in high precision spindle motor applications. In this paper, cogging torque is analytically calculated using energy method to show that Fourier spectra of airgap permeance function and airgap MMF function are the most important design parameters to control cogging torque. To control these functions, stator pole shoe pairing and magnet arc design are proposed to minimize cogging torque. As for optimization technique, genetic algorithm is applied to handle trade-off effects of design parameters. Results show that the proposed method can reduce the cogging torque effectively.

Study on Torque Analysis of Micro-Electromagnetic Clutch by Using FEM (FEM을 이용한 Micro-Electromagnetic Clutch 토크해석)

  • Piao Changhao;Cho Chongdu;Kim Myunggu;Pan Qiang
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.54 no.2
    • /
    • pp.60-65
    • /
    • 2005
  • This study tries to analyzes the static friction torque that generated in a micro-electromagnetic clutch by using FEM. For the purpose of design change and optimization of the micro-electromagnetic clutch, the static friction torque prediction is very important. We construct the axi symmetric FEM model for analyze the static friction torque and the real material properties are substituted to the FEM model. For a test, predicted static friction torque is compared with experimental one to discuss the rationality of torque analysis process. The analytical result agrees well to experimental data. explaining the validity of the mathematical process and FEM model.

Optimization of Hip Flexion/Extension Torque of Exoskeleton During Human Gait Using Human Musculoskeletal Simulation (인체 근골격 시뮬레이션을 활용한 인체 보행 시 외골격의 고관절 굴곡/신장 토크 최적화)

  • Hyeseon Kang;Jinhyun Kim
    • The Journal of Korea Robotics Society
    • /
    • v.18 no.1
    • /
    • pp.117-121
    • /
    • 2023
  • Research on walking assistance exoskeletons that provide optimized torque to individuals has been conducted steadily, and these studies aim to help users feel stable when walking and get help that suits their intentions. Because exoskeleton auxiliary efficiency evaluation is based on metabolic cost savings, experiments on real people are needed to evaluate continuously evolving control algorithms. However, experiments with real people always require risks and high costs. Therefore, in this study, we intend to actively utilize human musculoskeletal simulation. First, to improve the accuracy of musculoskeletal models, we propose a body segment mass distribution algorithm using body composition analysis data that reflects body characteristics. Secondly, the efficiency of most exoskeleton torque control algorithms is evaluated as the reduction rate of Metabolic Cost. In this study, we assume that the torque minimizing the Metabolic Cost is the optimal torque and propose a method for obtaining the torque.

Design and optimization of 900kW class PMSG, based on Unison U50 model (Unison U50 직접구동 영구자석 발전기를 기반으로 한 900kW급 동기발전기 설계 및 최적화)

  • Kim, Tae-Hun;Lee, Sang-Woo;Kim, Dong-Eon;Chung, Chin-Wha;Park, H.C.
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2009.11a
    • /
    • pp.423-426
    • /
    • 2009
  • POSTECH Graduate School of Wind Energy is trying to upgrade the PMSG used for Unison U50 to 900 kW class. Intensive optimization efforts are carried out the reduce the axial size and total weight of the generator while increasing the rated output to 900 kW. The generator features 3.32m stator inner radius, 671mm stator length, 84 pole, 25 rated rpm and 31.6kN/$m^2$ shear force density. To reduce the gross weight, the stronger magnetic material is applied with optimal magnet size resulting lowest cogging torque. Also, instead of stator skewing the stator, the magnet position along the circumference is optimized to further reduce the cogging torque. This scheme eliminates the stator skewing procedure and may enhance the productivity. This method also reduces the total harmonic distortion. In this report, upgrade method, no-load line to line voltage and phase voltage, cogging torque, loss calculations and thermal analysis are presented.

  • PDF

Numerical optimization of Wells turbine for wave energy extraction

  • Halder, Paresh;Rhee, Shin Hyung;Samad, Abdus
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • v.9 no.1
    • /
    • pp.11-24
    • /
    • 2017
  • The present work focuses multi-objective optimization of blade sweep for a Wells turbine. The blade-sweep parameters at the mid and the tip sections are selected as design variables. The peak-torque coefficient and the corresponding efficiency are the objective functions, which are maximized. The numerical analysis has been carried out by solving 3D RANS equations based on k-w SST turbulence model. Nine design points are selected within a design space and the simulations are run. Based on the computational results, surrogate-based weighted average models are constructed and the population based multi-objective evolutionary algorithm gave Pareto optimal solutions. The peak-torque coefficient and the corresponding efficiency are enhanced, and the results are analysed using CFD simulations. Two extreme designs in the Pareto solutions show that the peak-torque-coefficient is increased by 28.28% and the corresponding efficiency is decreased by 13.5%. A detailed flow analysis shows the separation phenomena change the turbine performance.

Copper Loss and Torque Ripple Minimization in Switched Reluctance Motors Considering Nonlinear and Magnetic Saturation Effects

  • Dowlatshahi, Milad;Saghaiannejad, Sayed Morteza;Ahn, Jin-Woo;Moallem, Mehdi
    • Journal of Power Electronics
    • /
    • v.14 no.2
    • /
    • pp.351-361
    • /
    • 2014
  • The discrete torque generation mechanism and inherently nonlinear magnetic characterization of switched reluctance motors lead to unacceptable torque ripples and limit the application of these motors. In this study, a phase current profiling technique and torque sharing function are proposed in consideration of magnetic saturation effects and by minimizing power loss in the commutation area between the adjacent phases. Constant torque trajectories are considered in incoming and outgoing phase current planes based on nonlinear T-i-theta curves obtained from experimental measurements. Optimum points on constant torque trajectories are selected by improving drive efficiency and minimizing copper loss in each rotor position. A novel analytic invertible function is introduced to express phase torque based on rotor position and its corresponding phase current. The optimization problem is solved by the proposed torque function, and optimum torque sharing functions are derived. A modification method is also introduced to enhance the torque ripple-free region based on simple logic rules. Compared with conventional torque sharing functions, the resultant reference current from the proposed method has less peak and effective values and exhibits lower copper loss. Experimental and simulation results from a four-phase 4 KW 8/6 SRM validate the effectiveness of the proposed method.