• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.83-84
• /
• 2015

In order to use the high-speed range of Interior Permanent Magnet Synchronous Motor(same as IPMSM above), the motor should be at flux weakening control status. High-speed range is called field weakening control region or constant power region, and explain the basic theory of flux weakening control used in the constant power region. Back electromotive force of IPMSM is measured. and field weakening conrtrol driving characteristics is configurated verification test. Through experimentation speed-torque characteristic curve, the efficiency variation corresponding to the current phase angl,the efficiency map were produced.

• Proceedings of the KIPE Conference
• /
• 2003.07b
• /
• pp.544-547
• /
• 2003

The purpose of this paper is to develop the straightforward design guidelines of PD/PID speed controller for Industry servo drives with plug and play concept. The controller gains are uniquely determined from the current control loop dynamics, speed loop delay, and mechanical parameters. In order to eliminate the mechanical friction uncertainties, an automatic PD/PI control mode switching algorithm Is introduced using online spectrum analysis of motor torque command. The dynamic performance of the proposed scheme assures a fast tracking response curve with minimal oscillation and settling time over the whole operating conditions. For comprehensive comparison of conventional PI control scheme, extensive test is carried out on actual servo system.

• Journal of the korean Society of Automotive Engineers
• /
• v.8 no.4
• /
• pp.56-65
• /
• 1986

This paper theoretically analyzed the relations between the out-put braking torque and the wheel cylinder pressure in the leading-trailing drum brake for heavy duty truck as the characteristics of friction in break lining, comparing with the results derived from full-scale inertial brake dynamometer test in actual braking condition to develop reliable brake system in extensive using conditions. The main results obtained are as follows; 1) The characteristic curve representing the relations between BEF (Brake Effectiveness Factor) and Friction coefficient derived from theoretical analysis are consistent with the experimental results of dynamometer test. 2) According to the results of dynamometer test, the friction coefficient of brake lining is subject to initial brake speed and the actual using temperature in brake system.

• Proceedings of the KIEE Conference
• /
• 1997.07b
• /
• pp.696-698
• /
• 1997

The marine diesel engine have been widely applied with a mechanical hydraulic governor to control the ship speed for long time. But it was recently very difficult for the mechanical hydraulic governor to control the speed of engine under the condition of low speed and low load because of jiggling by rough fluctuation of rotating torque and hunting by dead time of diesel engine. In order to analyze the speed control system the transfer function was converted from z to w transformation. The author proposed velocity control system with feedback loop by PID controller in order to stabilize for unstable area. The influence of dead time was discussed by Nichols chart and unit step response curve. It was confirmed through computer simulation that the performance improvement of a mechanical hydraulic governor can be obtained by PID controller.

• The KSFM Journal of Fluid Machinery
• /
• v.15 no.5
• /
• pp.5-10
• /
• 2012

An experimental test facility for the complete characteristics of pumps is constructed at KIMM(Korea Institute of Machinery and Materials). All sensors instrumented in test facility for measuring flow rate, pressure, force and moment are in-situ calibrated by primary method. This paper describes the test facility and test technique of the complete characteristics of pumps, together with an experimental test results for a reactor coolant pump which is designed at KIMM for the first time in Korea. The test results for the mixed-flow type pump of $n_s$=1.425 are presented by three curves: constant head, torque, and speed.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.26 no.4
• /
• pp.67-74
• /
• 2012

This paper presents the novel design and implementation of a switched reluctance motor with commutator. Unlike typical switched reluctance motor, this motor doesn't require semi-conductor devices and inverter circuits for driving. Instead, the brushes and commutator can make rotating field for driving the switched reluctance motor. Moreover, because this motor has no magnet, the total cost for manufacturing the motor is very cheap. In order to verify the usability of the proposed motor, the authors manufactured the prototype motor, and showed the torque-speed curve of the motor.

• Elastomers and Composites
• /
• v.30 no.1
• /
• pp.9-19
• /
• 1995

To make filler loaded conducting rubber which has the excellent electronical and physical properties, CR and NBR were mixed with magnetite$(Fe_3O_4)$. From the result of the study, vulcanization characteristics shows the upgrading curve as increase in filler concentration and CR has more torque than NBR. When elongation be higher, modulus comes to decreases. Tear strength gradually decrease after showing of the maximum point when is in the 100phr in all. Resilience is not good to cause the increase in filler concentration. In the electrical properties, conductivity becomes smaller when filler concentration is increased. The increase of voltage makes an conductivity grown, but the changed rate is weak. The influence of temperature hardly changes on increasing temperature. The morphology and the distribution for a conductivity filler through SEM were better, the more filler concentration increase, the shorter the particle interval is.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.62 no.2
• /
• pp.270-277
• /
• 2013

Single phase induction motor(SPIM) is used widely because it is driven by single phase source. However, the efficiency of the motor is not good due to saturation of magnetic material. To analyze the motor accurately, the magnetic saturation characteristics should be considered in analysis of equivalent circuit. In this paper, lumped parameter of circuit are derived from multi phase induction motor using method of symmetrical coordinates. Also, we presents a method for the equivalent circuit analysis of SPIM using magnetic saturation rate. The magnetic nonlinearity is considered deriving magnetizing reactance from voltage-current saturation curve. As a results, current characteristic, torque, output and efficiency are shown through analysis of equivalent circuit. A simulation results of SPIM will be used to improve the characteristics and efficiency of motor.

• Proceedings of the KIEE Conference
• /
• 2005.07b
• /
• pp.1144-1146
• /
• 2005

This paper presents the optimal design reducing the rotor inertia in order to improve the driving characteristic of BLDCM for robots. The parallel Genetic Algorithm is performed to rotor inertia minimization in optimal design. Also, velocity profile with finite jerk method is introduced to reduce vibration of BLDCM. As a result, a torque characteristic is same although rotor inertia is reduced 2/3 compared with prototype model. And, maximum vibration value is reduced by 63.4[%1 according to apply finite jerk.

• Journal of the Korean Magnetics Society
• /
• v.5 no.5
• /
• pp.465-469
• /
• 1995

We have investigated the effects of deposition angle on structural and magnetic properties of e-beam evaporated ${(4-{\AA}\;Co/9.2-{\AA}\;Pt)}_{23}$ multilayer thin films prepared on tilted substrates. It was found that the [111] crystallographic orientations of the multilayer thin films were not aligned with colummar growth orientations and they were remained to be normal to the substrate planes even though the deposition angle was severely oblique up to $60^{\circ}$. The analysis of the torque curve reveal that the intrinsic anisotropy energy was monotonically decreased with the deposition angle but the easy axis orientation parallel to the substrate normal was not much influenced by deposition angle.