• 제목/요약/키워드: Computer Applied Engineering

검색결과 4,507건 처리시간 0.042초

블루투스를 이용한 보안을 위한 무선 센서네트워크의 구현 (An implementation of wireless sensor network for security system using Bluetooth)

  • 김재완;김병국;엄두섭
    • 한국정보처리학회:학술대회논문집
    • /
    • 한국정보처리학회 2004년도 춘계학술발표대회
    • /
    • pp.1501-1504
    • /
    • 2004
  • We describe a Bluetooth wireless sensor network for security systems, which includes the implementation issues about system architecture, power management, self-configuration of network, and routing. We think that the methods or algorithms described in this paper can be easily applied to other embedded Bluetooth applications for wireless networks.

  • PDF

Torque Ripple Minimization Scheme Using Torque Sharing Function Based Fuzzy Logic Control for a Switched Reluctance Motor

  • Ro, Hak-Seung;Lee, Kyoung-Gu;Lee, June-Seok;Jeong, Hae-Gwang;Lee, Kyo-Beum
    • Journal of Electrical Engineering and Technology
    • /
    • 제10권1호
    • /
    • pp.118-127
    • /
    • 2015
  • This paper presents an advanced torque ripple minimization method of a switched reluctance motor (SRM) using torque sharing function (TSF). Generally, TSF is applied into the torque control. However, the conventional TSF cannot follow the expected torque well because of the nonlinear characteristics of the SRM. Moreover, the tail current that is generated at a high speed motor drive makes unexpected torque ripples. The proposed method combined TSF with fuzzy logic control (FLC). The advantage of this method is that the torque can be controlled unity at any conditions. In addition, the controller can track the torque under the condition of the wrong TSF. The effectiveness of the proposed algorithm is verified by the simulations and experiments.

An Analysis on the Adequate Level of Capacity Price from a Long-Term Generation Expansion Planning Perspective: the Case of Korea

  • Kim, Hyoungtae;Lee, Sungwoo;Kim, Tae Hyun;Shin, Hansol;Kim, Wook
    • Journal of Electrical Engineering and Technology
    • /
    • 제13권6호
    • /
    • pp.2203-2211
    • /
    • 2018
  • Capacity payment mechanism has been adopted as the incentive scheme to achieve resource adequacy in Korean electricity market, however, the level of capacity price has been controversial due to its insufficient extent to incur financial loss for certain generators. Therefore, a new method is proposed to estimate the proper level of capacity price incorporating profitability of market participants and resource adequacy in this paper. The proposed method is successfully applied to test system based on Korean power system.

Dynamic Characteristic Analysis of Electric Actuator for 1 kV/3.2 kA Air Circuit Breaker Based on the Three-link Structure

  • Lee, Seung-Min;Kang, Jong-Ho;Kwak, Sang-Yup;Kim, Rae-Eun;Jung, Hyun-Kyo
    • Journal of Electrical Engineering and Technology
    • /
    • 제6권5호
    • /
    • pp.613-617
    • /
    • 2011
  • In the present paper, a new type of electrical actuator, an electromagnetic force driving actuator (EMFA), applicable to air circuit breaker is developed and analyzed. Transient analysis is performed to obtain the dynamic characteristics of EMFA. The distribution of static magnetic flux is obtained using the finite element method. The coupled problems of electrics and mechanics governing equations are solved using the time-difference method. According to the interception rate of each contactor, investigation of the contactor spring load condition is conducted and applied to the threelink system. Comparisons of the dynamic characteristics of the three-link simulation and experimental data are performed.

전기자동차 무선 충전용 수신패드 식별코일의 형상 설계 및 운용 방안 (Receiving Pad Identification Coil for Wireless Charging of Electric Vehicle)

  • 심동현;조현우;허훈;이주아;손원진;이병국
    • 전력전자학회논문지
    • /
    • 제27권6호
    • /
    • pp.455-463
    • /
    • 2022
  • This study proposes a receiving pad identification coil for wireless charging of electric vehicles. The proposed coil identifies the shape of the receiving pad through magnetic coupling with the receiving pad. Therefore, the shape of the coil is designed to show the different magnetic properties of each receiving pad. The accuracy of this design is verified through finite element method simulation. Furthermore, the operation method of the secondary pad identification circuit is described, and the appropriate magnitude and length of the pulse voltage applied to this circuit for receiving pad identification are derived through simulation. The performance of the proposed identification coil set is verified by the experimental results.

Koch Fractal Shape Microstrip Bandpass Filters on High Resistivity Silicon for the Suppression of the 2nd Harmonic

  • Kim, Ii-Kwon;Kingsley Nickolas;Morton Matthew A.;Pinel Stephane;Papapolymerou John;Tentzeris Manos M.;Laskar Joy;Yook, Jong-Gwan
    • Journal of electromagnetic engineering and science
    • /
    • 제6권4호
    • /
    • pp.235-243
    • /
    • 2006
  • In this paper, the fractal shape is applied to microstrip band pass filters and integrated on a high-resistivity Si substrate to solve conventional $2^{nd}$ harmonic problem. Conventional microstrip coupled line filters are popular in RF front ends, because they can be easily fabricated and integrated with other RF components. However, they typically have large second harmonics that can cause unwanted interference in interested frequency bands. Without any additional filters, the proposed Koch shape filters have suppressed the $2^{nd}$ harmonics by about -40 dB, so they can be used in systems such as direct conversion receiver with stringent harmonic suppression requirements.

Effects of V-Skew on the Torque Characteristic in Permanent Magnet Synchronous Motor

  • Lee, Jong Gun;Lee, Ki Wook;Park, Gwan Soo
    • Journal of international Conference on Electrical Machines and Systems
    • /
    • 제2권4호
    • /
    • pp.390-393
    • /
    • 2013
  • In this paper, we proposed how the V-skew applied of the rotor to inprove the characteristics of cogging torque in large PMSM. Large PMSM is difficult to apply a pitch of the diagonal magnetic skew because of the motor's structure and making. In addition, the force in the direction of z-axis occurs when the diagonal skew is applied. So we are applying the optimal v-skew to reduce torque ripple and cogging torque because this reduces the noise and vivration on the motor. Throug FEM dD analysis, we studied to find the optimal v-skew angle for reducing torque ripple.

DP Formulation of Microgrid Operation with Heat and Electricity Constraints

  • Nguyen, Minh Y;Choi, Nack-Hyun;Yoon, Yong-Tae
    • Journal of Power Electronics
    • /
    • 제9권6호
    • /
    • pp.919-928
    • /
    • 2009
  • Microgrids (MGs) are typically comprised of distributed generators (DGs) including renewable energy sources (RESs), storage devices and controllable loads, which can operate in either interconnected or isolated mode from the main distribution grid. This paper introduces a novel dynamic programming (DP) approach to MG optimization which takes into consideration the coordination of energy supply in terms of heat and electricity. The DP method has been applied successfully to several cases in power system operations. In this paper, a special emphasis is placed on the uncontrollability of RESs, the constraints of DGs, and the application of demand response (DR) programs such as directed load control (DLC), interruptible/curtaillable (I/C) service, and/or demand-side bidding (DSB) in the deregulated market. Finally, in order to illustrate the optimization results, this approach is applied to a couple of examples of MGs in a certain configuration. The results also show the maximum profit that can be achieved.

Implementation of low power algorithm for near distance wireless communication and RFID/USN systems

  • Kim, Song-Ju;Hwang, Moon-Soo;Kim, Young-Min
    • International Journal of Contents
    • /
    • 제7권1호
    • /
    • pp.1-7
    • /
    • 2011
  • A new power control algorithm for wireless communication which can be applied to various near distance communications and USN/RFID systems is proposed. This technique has been applied and tested to lithium coin battery operated UHF/microwave transceiver systems to show extremely long communication life time without battery exchange. The power control algorithm is based on the dynamic prediction method of arrival time for incoming packet at the receiver. We obtain 16mA current consumption in the TX module and 20mA current consumption in the RX module. The advantage provided by this method compared to others is that both master transceiver and slave transceiver can be low power consumption system.

Coupling Particles Swarm Optimization for Multimodal Electromagnetic Problems

  • ;;고창섭
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2009년도 제40회 하계학술대회
    • /
    • pp.786_787
    • /
    • 2009
  • This paper proposes a novel multimodal optimization method, Coupling particles swarm optimization (PSO), to find all optima in design space. This method based on the conventional Particle Swarm Optimization with modifications. The Coupling method is applied to make a couple from main particle and then each couple of particles searches its own optimum by using non-stop-moving PSO. We tested out our method and other one, such as ClusteringParticle Swarm Optimization and Niche Particle Swarm Optimization, on three analytic functions. The Coupling Particle Swarm Optimization is also applied to solve a significant benchmark problem, the TEAM workshop benchmark problem 22

  • PDF