• Title/Summary/Keyword: Operation control

Search Result 9,609, Processing Time 0.038 seconds

A Study on the Hierarchical Real-time Operation Control and Monitoring for an Flexible Manufacturing System (유연생산시스템의 계층구조적 실시간 운용제어 및 모니터링에 관한 연구)

  • Kim, Jong-Won
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.9 no.4
    • /
    • pp.36-43
    • /
    • 1992
  • This paper presents a hierarchical real-time operation control and monitoring scheme of the FMS/CIM center which has been implemented at the Automation and Systems Research Institute of Seoul National University. The hierarchical structure of the whole scheme consists of three lavers. The upper layer is in charge of on-line scheduling, computer network control, shop-floor monitoring and command generation for AGV dispatching, machining, assembly, inspection, set-up, etc. The middle layer has six modules, which are installed in the FMS host computer with the upper layer and run on the multi-tasking basis. Each module is connected to one of six cell controllers distributed in the FMS model plant and transfers operation command down to each cell controller through the Ethernet/TCP-IP local area network. The lower layer is comprised of six cell control software modules for machining cell, assembly cell, inspection cell, set-up stations. AS/RS and AGV. Each cell controller reports the status of the manufacturing facilites to the middle layer as well as ecxecuting the appropriate sequence control of the manufacturing processes.

  • PDF

A Study on Improvement of the Interface Control of NPP Construction and Operation Activities

  • Chung, Ku-Young;Lee, Woo-Ho;Lee, Jae-Hun
    • Proceedings of the Korean Nuclear Society Conference
    • /
    • 2005.05a
    • /
    • pp.1221-1222
    • /
    • 2005
  • Interface control activities during the nuclear power plant (NPP) construction and operation have been reviewed for enhancing the safety of NPP. The primary focus of the study is given on analysis of lessons learned from the recent significant events of Korean Standard Nuclear Power plant (KSNP), such as a series of break-off of thermal sleeves at YGN 5 & 6 and radioactivity leak at YGN 5, in respect of interface control. Based on the results of the analysis, this study recommends measures for the improvement of interface control among utility and technical supporting organizations (TSO), and suggests new regulatory systems, such as reporting of safety significant non-conformances, to effectively verify the adequacy of interface control activities during construction and operation of NPPs.

  • PDF

A Study on Appropriateness of Performance Criteria of Smoke Control System for Underground Spaces (I) (지하공간에 대한 제연설비 성능기준의 적정성 고찰(I))

  • Ahn, Chan-Sol;Kim, Heung-Youl;Yoo, Yong-Ho;Jeon, Gyu-Yeop
    • Proceedings of the SAREK Conference
    • /
    • 2008.11a
    • /
    • pp.103-106
    • /
    • 2008
  • This study is intended to evaluate the characteristics of smoke spreading and the appropriateness of evacuation time extended by operation of smoke control system during fire within the underground space of the building structured in compliance with the smoke control system performance criteria from the local fire safety standard, which has been currently applied to the buildings in Korea. Using the heat release per unit weight of the combustibles, a numerical analysis both in case of smoke control system in operation and the system not in operation was carried out at the several different shopping malls. From the viewpoint of securing the evacuation time, the results were compared in an attempt to assess the appropriateness of the fire safety criteria.

  • PDF

Control of RC-Helicopter by Using Fuzzy Sliding Mode Controller

  • Hiramatsu, Tomoyasu;Miyazaki, Michio
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1998.10a
    • /
    • pp.210-214
    • /
    • 1998
  • Radio-Controlled helicopter has superior movement abilities like as hovering or backward move. So it has been used as a sprinkler of agricultural medicines or an observer of dangerous area such as a volcano, etc. But its operation is not simple because it has many control factors and they interfere with each other. Therefore the helicopter is not controlled by simple theory in the case of automatic operation. Then fuzzy sliding mode control, which has fastness, fineness and robustness, is thought to be suitable to satisfy various requirements of the helicopter operation. In this work, the fuzzy sliding mode control was applied to the flying of RC helicopter, As tile result, it was controlled with good performance.

  • PDF

Operation Scheme for a Wind Farm to Mitigate Output Power Variation

  • Lee, Sung-Eun;Won, Dong-Jun;Chung, Il-Yop
    • Journal of Electrical Engineering and Technology
    • /
    • v.7 no.6
    • /
    • pp.869-875
    • /
    • 2012
  • Because of the nature of wind, the output power of wind turbines fluctuates according to wind speed variation. Therefore, many countries have set up wind-turbine interconnection standards usually named as Grid-Code to regulate the output power of wind farms to improve power system reliability and power quality. This paper proposes three operation modes of wind farms such as maximum power point tracking (MPPT) mode, single wind turbine control mode and wind farm control mode to control the output power of wind turbines as well as overall wind farms. This paper also proposes an operation scheme of wind farm to alleviate power fluctuation of wind farm by choosing the appropriate control mode and coordinating multiple wind turbines in consideration of grid conditions. The performance of the proposed scheme is verified via simulation studies in PSCAD/EMTDC with doubly-fed induction generator (DFIG) based wind turbine models.

A Study on Three Parallel Operation Control Algorithm of Thyristor Dual Converter System for Urban Railway Substation (도시 철도용 사이리스터 듀얼 컨버터 시스템의 3병렬 운전 제어 기법에 관한 연구)

  • Kim, Sung-An;Han, Sung-Woo;Cho, Yun-Hyun
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.66 no.2
    • /
    • pp.459-467
    • /
    • 2017
  • An urban railway power substation consists of three thyristor dual converters. Two converters are connected to up and down trolley line to supply the electric energy or feed the regenerative energy back to the distribution. When the two converters break down, the remaining converter is used in an emergency. One thyristor dual converter system (TDCS) manages the energy of two or three railway stations. If the TDCS fails, the trains stop operating. To solve the problem, this paper proposes the three parallel operation control algorithm of thyristor dual converter system using the emergency converter. The broken TDCS can be replaced by the emergency converter in other TDCS. The effectiveness of this proposed control is verified by simulation.

The speed regulation and fixed point parking control of urban railway ATO considering unknown running resistance (미지의 주행저항을 고려한 도시철도차량 ATO의 속도추종 및 정밀정차 제어)

  • 변윤섭;한성호;김길동;백광선;한영재
    • Proceedings of the KSR Conference
    • /
    • 1999.11a
    • /
    • pp.280-287
    • /
    • 1999
  • An automatic train operation(ATO) system executes the operation of constant speed travelling and fixed point parking by using microprocessors instead of drivers manual operation. This paper describes the mathematical model for the train considering unknown disturbances which consist of start resistance, travelling resistance, slope resistance, curve resistance, and so on. The speed controller of ATO system is designed by considering the disturbances. The simulation is executed to verify the speed control and fixed point parking performance and to compare its performance with that of a PID-type ATO control system under disturbances. Simulation results show that the control performance of gain scheduled control scheme fur ATO system is better than that of the conventional PID controller.

  • PDF

Optimal Reservoir Operation Using Goal Programming for Flood Season (Goal Programming을 이용한 홍수기 저수지 최적 운영)

  • Kim, Hye-Jin;Ahn, Jae-Hwang;Choi, Chang-Won;Yi, Jae-Eung
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.11 no.2
    • /
    • pp.147-156
    • /
    • 2011
  • The purpose of multipurpose reservoir operation in flood season is to reduce the peak flood at a control point by utilizing flood control storage or to minimize flood damage by controlling release and release time. Therefore, the most important thing in reservoir operation for flood season is to determine the optimal release and release time. In this study, goal programming is used for the optimal reservoir operation in flood season. The goal programming minimizes a sum of deviation from the target value using linear programming or nonlinear programming to obtain the optimal alternative for the problem with more than two objectives. To analyze the applicability of goal programming, the historical storm data are utilized. The goal programming is applied to the reservoir system operation as well as single reservoir operation. Chungju reservoir is selected for single reservoir operation and Andong and Imha reservoirs are selected for reservoir system operation. The result of goal programming is compared with that of HEC-5. As a result, it was found that goal programming could maintain the reservoir level within flood control level at the end of a flood season and also maintain flood discharge within a design flood at a control point for each time step. The goal programming operation is different from the real operation in the sense that all inflows are assumed to be given in advance. However, flood at a control point can be reduced by calculating the optimal release and optimal release time using suitable constraints and flood forecasting system.

An Improvement on low Speed Operation Performances of DTC for 3-level Inverter-fed Induction Motors (3레벨 인버터로 구동되는 유도전동기 직접토크제어의 저속성능 개선)

  • Lee, Kyo-Beum;Song, Joong-Ho;Choy, Ick;Kim, Kwang-Bae;Yoo, Ji-Yoon
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.49 no.10
    • /
    • pp.693-700
    • /
    • 2000
  • A direct torque control algorithm for 3-level inverter-fed induction motors is presented. Conventional voltage selection methods provoke some problems such as stator flux drooping phenomenon and undersirable torque control appeared especially at the low speed operation. To overcome these problems, a proposed method uses intermediate voltage vectors, which are inherently generated in 3-level inverters. In the proposed algorithm, both subdivision of the basic switching sectors and applications of tntermediated voltages improve the low speed operation characteristics. This algorithm basically considers applications in which direct torque controlled induction motors are fed by 3-level inverters with low switching frequency around 500Hz. An adaptive observer is also employed to bring better responses at the low speed operation, by estimating some state-variables, motor speed and motor parameters which take a deep effect on the performance of the low speed operation. Simulation and experiment results verify effectiveness of the proposed algorithm.

  • PDF

An Arithmetic System over Finite Fields

  • Park, Chun-Myoung
    • Journal of information and communication convergence engineering
    • /
    • v.9 no.4
    • /
    • pp.435-440
    • /
    • 2011
  • This paper propose the method of constructing the highly efficiency adder and multiplier systems over finite fields. The addition arithmetic operation over finite field is simple comparatively because that addition arithmetic operation is analyzed by each digit modP summation independently. But in case of multiplication arithmetic operation, we generate maximum k=2m-2 degree of ${\alpha}^k$ terms, therefore we decrease k into m-1 degree using irreducible primitive polynomial. We propose two method of control signal generation for the purpose of performing above decrease process. One method is the combinational logic expression and the other method is universal signal generation. The proposed method of constructing the highly adder/multiplier systems is as following. First of all, we obtain algorithms for addition and multiplication arithmetic operation based on the mathematical properties over finite fields, next we construct basic cell of A-cell and M-cell using T-gate and modP cyclic gate. Finally we construct adder module and multiplier module over finite fields after synthesizing ${\alpha}^k$ generation module and control signal CSt generation module with A-cell and M-cell. Next, we constructing the arithmetic operation unit over finite fields. Then, we propose the future research and prospects.