• 한국산학기술학회논문지
• /
• 제7권2호
• /
• pp.126-130
• /
• 2006

PLC는 산업용 제어시스템에서 널리 사용되고 있으며, 중요한 역할을 하고 있다. PLC에서 사용되는 언어중 SFC는 이산 제어 프로그램에서 순차제어 논리의 기술에 적합한 그래픽 언어이며, SFC로 공정제어 시스템을 구현할 때는 분산제어 구조와 계층제어 구조로 구현하게 된다. 계층제어 구조에서는 서브시스템 간에 동기를 맞추기 위해서 서브시스템은 별도로 구성하고 동기신호만을 주고받게 된다. 그러면 메모리 효율 및 시스템 성능이 좋지 않게 된다. 본 논문에서는 계층제어 구조에서 메모리 효율을 향상시키는 방법을 제안하였고, 실례를 통해 그의 타당성을 확인하였다.

• 대한산업공학회지
• /
• 제19권1호
• /
• pp.61-71
• /
• 1993

We focus on a way of combining the Monte Calro methods of antithetic variates and control variates to reduce the variance of the estimator of the mean response in a simulation experiment. Combined Method applies antithetic variates (partially) for driving approiate stochastic model components to reduce the vaiance of estimator and utilizes the correlations between the response and control variates. We obtain the variance of the estimator for the response analytically and compare Combined Method with control variates method. We explore the efficiency of this method in reducing the variance of the estimator through the port operations model. Combined Method shows a better performance in reducing the variance of estimator than methods of antithetic variates and control variates in the range from 6% to 8%. The marginal efficiency gain of this method is modest for the example considered. When the effective set of control variates is small, the marginal efficiency gain may increase. Though these results are from the limited experiments, Combined Method could profitably be applied to large-scale simulation models.

• 한국산업융합학회 논문집
• /
• 제24권6_1호
• /
• pp.645-658
• /
• 2021

In this paper, we propose a new approach to intelligent control based on fuzzy logic for work efficiency improvement of smart factory by the applicaion of ariticulated robot. The intelligent control that is applied to the working process by the joint of robotic manipulator is the main focus to improve a work efficiency for implimentation of smart factory in general manufacturing process. In this study, we propose a new method of a fuzzy model and then develop a nonlinear relationship between interaction forces and manipulator position using a fuzzy model. The reliability of the proposed control method is illustrated by simulation and experiments.

• 조명전기설비학회논문지
• /
• 제25권7호
• /
• pp.15-25
• /
• 2011

This proposes an online loss minimization algorithm for series PI(SPI) based interior permanent magnet synchronous motor(IPMSM) drive to yield high efficiency and high dynamic performance over wide speed range. The loss minimization algorithm is developed based on the motor model. In order to minimize the controllable electrical losses of the motor and thereby maximize the operating efficiency, the d-axis armature current is controlled optimally according to the operating speed and load conditions. For vector control purpose, a SPI is used as a speed controller which enables the utilization of the reluctance torque to achieve high dynamic performance as well as to operate the motor over a wide speed range. Also, this paper proposes current control of model reference adaptive fuzzy controller(MFC), and estimation of speed using artificial neural network(ANN) controller. The proposed efficiency optimization control, SPI, MFC, ANN in this paper is applied to IPMSM drive system, the validity of this paper is proved by analyzing response characteristics in variety operating conditions.

• 전기학회논문지
• /
• 제67권9호
• /
• pp.1239-1248
• /
• 2018

This paper proposes a fault tolerant and high efficiency operation algorithm for a 4 LEG DC/DC converter for a battery energy storage system(BESS) forming a main power source in a standalone DC micro grid. The BESS for the main power supply in the stand-alone DC micro-grid is required to operate at high speed according to fault tolerant control and load by operating at all times. Fault-tolerance control changes the short-circuit fault to an open-circuit fault by using a fuse in case of leg fault in 4 legs, and operates stably through phase shift control. In addition, considering the loss of the power semiconductor, the number of LEG operation is adjusted to operate at high efficiency in the full load region. In this paper, fault tolerant control and high efficiency operation algorithm of DC/DC converter for BESS in standalone DC micro grid is presented and it is proved through simulation and experiment.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
• /
• pp.428-433
• /
• 2001

This paper presents the control algorithm for maximum efficiency drives of an induction motor system with the high dynamic performance. This system uses a simple model of the induction motor that includes equations of iron losses. The model, which only requires the parameters of induction motor, is referred to a field-oriented frame. The minimum point of the input power can be obtained at the steady state condition. The reference torque and flux currents for the vector control of induction motors are calculated by the optimal efficiency control algorithm. The drive system with the proposed efficiency optimization controller has been implemented by a 32 bit floating point TMS320C32 DSP chip. The results show the effectiveness of the control strategy proposed for the induction motor drive.

• 한국항해항만학회지
• /
• 제34권4호
• /
• pp.265-270
• /
• 2010

The national VTS was launched in 1993, and has adopted a harbour-oriented control method which is unable to consider enough characteristics of its work. However, for the past 17 years, the characteristics has changed due to increased amount of vessels. Up to now the domestic Vessel Traffic Service has adopted harbour-oriented control method which is unable to consider enough characteristics of its work. However, developed countries have carried out waters-oriented control method, according to the using areas of ships, to be well considered the characteristics of control for increasing efficiency of it. Especially, VTS of Daesan, Pyeongtaek and Inchon harbour can have confusions of control because of overlapped service areas of it. Therefore, in this paper suggested a new Sector Division that the relevants waters is divided into 3 operational Regions and these are divided into nine sectors again, for the purpose of improving the efficiency and the concentration of VTS.

• 전력전자학회논문지
• /
• 제22권5호
• /
• pp.423-430
• /
• 2017

This paper proposes a control methodology for a high efficiency operation of an inductive power transfer (IPT) converter by combining full bridge (FB) and half bridge (HB) controls. To apply the proposed control to the IPT converter, the characteristics of each control method are analyzed. By examining the output voltages of the IPT converter and a theoretical loss analysis, the control shifting points between FB and HB controls are evaluated in accordance with the coupling coefficients and the load. Based on the control shifting points, the FB-HB control algorithm is implemented. By applying FB-HB control, high efficiency operation at the light load condition can be achieved.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
• /
• pp.99-102
• /
• 2006

This paper proposes a DITC(Direct Instantaneous Torque Control of SRM (Switched Reluctance Motor) using a novel 4-level converter for smooth torque control and high efficiency. DITC of SRM is very useful for smooth torque control, but the driving efficiency is low due to advanced current that does not produce torque. For the high efficiency control of SRM, fast excitation and demagnetization of phase current are required. A novel 4-level converter and a new control scheme are present to improve the driving efficiency. The proposed DITC of SRM using 4-level converter is verified by computer simulation.

• 조명전기설비학회논문지
• /
• 제22권5호
• /
• pp.58-63
• /
• 2008

유도전동기 고정자자속 기준제어의 최대효율제어를 위한 초기자속 값의 계산방법을 제안한다. 3개의 자속에 대한 입력을 계산한 후 3점을 2차 보간하여 2차 함수의 최소점, 즉 입력이 최소가 되는 자속을 구하고, 이 자속을 초기 값으로 하여 최대효율제어를 수행한다. 시뮬레이션 결과 기존의 방법에 비해서 제안한 방법에 의하여 최대효율점으로의 수렴시간이 단축됨을 보인다.