• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.2
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• pp.77-82
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• 2012

To share the lanes with conventional vehicles, traffic operation strategy is needed for NEV (Neighborhood Electric Vehicle). Because NEV cannot accelerate sharply as fast as common car include gasoline, diesel and LPG cars, they may interrupt traffic conditions and make traffic delay. After green lights turn on, all vehicles run through the street including NEV, but NEV have a maximum speed which is 50km/h. It can be an obstacle for following vehicles and will make traffic delay of the intersection. In this reason, we need to organize traffic systems like queue jump with priority traffic signal. To analyze the necessity for NEV road operations, we simulate three scenarios in congested and non-congested conditions. First is that we examine the condition which is mixed NEV and cars on the road, the second one is that we set up lane only NEV can accepted in simulation and last one is making queue jump lane and providing priority signal for NEV. In conclusion, we can conclude that making lane only for NEV is effective to improve travel speed when rate of NEVs is over 20%. Also queue jump lane and priority signal cannot make good effect to intersection delay and average speed.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.5
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• pp.124-134
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• 2011

To make popular the NEV(Neighborhood Electric Vehicles) uses, it must be considered the supply of infrastructure and the political decision for NEV. However, the guidelines of infrastructure for NEV are not prepared. The guidelines of infrastructure for NEV should be performed in many research and case. The purpose of this study is to reveal the influence of NEV on the two-lane highway traffic flows by TWOPAS simulation model. The main items to check the influence are Average Travel speed, Percent Time Spent Following and Total Delay. The scenario were setup by traffic volume. And the NEV percentages are changed from 1% ~ 30%. The scenario 1 which traffic volume are 650veh/h and the scenario 4 which traffic volume are 2,600veh/h are less influenced by NEV, compare to scenario 2, scenario 3. Because the scenario 1 is more free to make passing other cars and Scenario 4 is fully saturated with existing traffic volumes. The urban two-lane highway which has much traffic volume and the rural two-lane highway which has little traffic volume has affinity for NEV than the other two-lane highway.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.10 no.1
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• pp.66-74
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• 1996

최근 진행파형 초음파 모터는 그 구조가 간단하고, 저속 고 토크이어서 직접 구동()용으로 많은 호응을 얻고 있다. 또한 응답이 빠르고, 정지 토크가 크며 설계자유도가 높을 뿐만 아니라 운전시 소음이 없고 자계에 강해 자동화 설비 분야 등 산업 전반에 걸쳐 매우 각광을 받고 있다. 본 논문에서는 초음파 모터의 2상 입력전원의 위상차를 조절하여 속도와 토크 특성을 이론적으로 고찰하고, 이를 토대로 위상차 제어기를 설계 제작하였다. 그리고 이를 이용하여 위상차 제어방식을 채용한 경우 초음파 모터의 위치 및 속도제어는 물론 간단한 알고리즘으로 토크 제어가 가능함을 시뮬레이션과 실험을 통하여 검토하였다. 실험 결과 위상차 변화에 따라 속도가 토크가 거의 비례해서 변화하였다. 이것으로 전원 전압의 위상차 조절을 통해서 속도와 토크를 동시에 제어할 수 있을 뿐만 아니라 토크센서 없이 각도 센선 만으로도 위치제어는 물론 토크 제어도 큰 오차 없이 행할 수 있음을 밝혔다.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.135-140
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• 2011

The battery pack, a main component of NEV(Neighborhood Electric Vehicle), needs cooling system when it is charging or discharging to prevent the degradation of the battery charging efficiency. The purpose of this study is to analyse the effects of cooling methods, changing positions of inlet and outlet and changing area ratios of inlet and outlet. It has been observed that in the point of uniform cooling suction from the exit side is more efficient than blowing from the inlet. And there is a suitable inlet/outlet area ratio in maximizing the mass flow rate. The numerical analyse using a commercial code STAR-CCM+ version 4.02 were used for the study.

• Journal of computational fluids engineering
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• v.16 no.3
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• pp.82-87
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• 2011

The battery pack, a main component of NEV(Neighborhood Electric Vehicle), needs cooling system when it is charging or discharging to prevent the degradation of the battery charging efficiency. The purpose of this study is to analyse the effects of cooling methods, changing positions of inlet and outlet and changing area ratios of inlet and outlet. It has been observed that in the point of uniform cooling, suction from the exit side is more efficient than blowing from the inlet. And there is a suitable inlet/outlet area ratio in maximizing the mass flow rate. A commercial code, STAR-CCM+(ver. 4.02), was used for the numerical study.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.10 no.6
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• pp.88-95
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• 1996

The ultrasonic motor(USM) has good characteristics such as compact size, silent motion, high speed responce, low speed and high torque. The USM is driven by 2-phase AC electricity. The control parameters of USM are voltage, phase, and frequency of input powers, etc. In this paper, a voltage difference control is proposed. The voltage difference control has more advantage than phase difference control. Specially, current and power is lower than that of phase difference control. For this voltage diffrence control, we designed USM controller to adjust volatage and phase using PLSI(Programmable Large Scale Integration).

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.4
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• pp.55-63
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• 2018

In recent years, with the growing interest in electric vehicles, the development of a Neighborhood Electronic Vehicle (NEV) made for urban driving is accelerating. Existing NEVs are set to ~0.3 - 0.35 with more emphasis on performance rather than minimizing air resistance. In this paper, a NEV with a streamlined car body is proposed. The shape of dolphins and sharks was applied to the car body to minimize the air resistance generated when driving. Also, the performance of the vehicle was estimated by calculating the traction force and the roll couple, etc. To check the drag coefficient of the car body, finite element analysis software (COMSOL Multiphysics) was used. The frame of the vehicle is divided into the forward and the rear parts. Carbon pipe is used for the frame by MIG welding. The car body of the vehicle was fabricated by forming carbon fiber. This study confirmed the general possibility of using NEVs through driving experiments.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.11 no.5
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• pp.86-92
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• 1997

An ultrasonic motor(USM) has good characteristics such as compact size, silent motion, high speed responce, low speed and high torque. The USM is driven by 2-phase AC electricity. The control parameters of USM are voltage, phase, and frequency of input powers, etc. In this paper, the fine elasticity and viscosity control with no force feedback can be implemented by a phase difference parameter. Experiment results show the change of torque with regard to elasticity and viscosity. Therefore the USM can be used as a micro-actuator in the automation field of the installation.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.9
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• pp.552-561
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• 2004

This paper is concerned with a new speed sensorless induction motor scheme which can be successfully applied to at any speed including even zero speed. The proposed method is robust against rotor resistance variations. In addition, simultaneous on-line estimations of speed and rotor resistance are realized based on a feedforward type torque control approach. The rotor flux with a low frequency sinusoidal waveform has been utilized to help the simultaneous estimation for both speed and rotor resistance. The control scheme has no current minor loop to determine voltage references. Since the proposed estimation does not depend on any derivative terms of currents and stator voltages, it offers a good performance at extremely low speed region for sensorless induction motor. Furthermore, the proposed control is simply using motor parameters and stator currents without determining any PI gains for current feedback and any signal injection for the rotor resistance estimation. Finally, both simulation and experimental results are given to show the effectiveness of this method.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.814_815
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• 2009

본 논문은 로봇관절 구동 및 제어에 활용될 중공모터의 설계 및 특성해석에 대해 연구하였다. 로봇관절에 사용될 중공모터의 경우고 토크출력이 요구될 뿐만 아니라, 저속에서 제어 및 구동 신뢰성이 높은 운전특성이 요구된다. 또한 로봇 관절에 활용하기 위하여 배선처리가 간편한 중공타입의 구조가 요구된다. 따라서 우리는 로봇 구동 및 경량화가 가능하도록 유성기어와 결합이 가능한 외전형 타입의 영구자석 동기전동기의 설계 및 특성해석을 하였다. 먼저 로봇 관절에 적합하도록 FEA 기법을 이용하여 설계하였으며, 실제 시작기 모델을 제작하여 성능실험을 통해 제안된 모터의 특성을 분석하였다.