• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2002년도 ITC-CSCC -2
• /
• pp.841-843
• /
• 2002

In this paper, we develop the remote control device of vending machine through internet. This device can control the temperature, humidity and on/off switch. This device is operated by the Java based TCP/IP control program.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2002년도 전력전자학술대회 논문집
• /
• pp.697-700
• /
• 2002

In this paper, we proposed the micro web-server Implementation on Strong ARM processor with embedded Linux. The parallel port connecting parallel I/O is controlled via HPPT protocol and web browser program. HTTP protocol is ported into Linux and the micro web server program and port control program are installed on-board memory using CGI to be accessed by web browser, such as Internet Explore and Netscape. 8bit LED and DIP switches are connected to the processor port and the switch input status is monitored and the LED output is controlled from remote hosts vie internet. The result of the proposed embedded micro-web server can be used in automation systems, remote distributed control via internet using web browser.

• KIEAE Journal
• /
• 제12권1호
• /
• pp.119-125
• /
• 2012

The objective of this study is to evaluate the electric lighting energy consumption carried out by Daysim program. A comparison between the measurement and simulated exterior global horizontal illuminance shows differences about 10% and it is very similar to the measurement. The interior illuminance simulated by Daysim are 18.9% lower than the measurement and simulated lighting energy consumption is 10% lower than the measurement. Corrected annual lighting energy simulation results show that the best case is the combination of occupancy switch-off and dimming system with automatic controlled blinds (E-3). In case of no blinds, it occasionally derives the minimum lighting energy consumption but it causes the glare, so we need to be careful for choosing the control strategy. For the overcast sky, the lighting energy consumption is not changed significantly by control strategy while the lighting energy in the clear sky is changed noticeably. So we must know the right strategy for each case to control the electric lights and blinds.

• 전기학회논문지
• /
• 제59권12호
• /
• pp.2125-2130
• /
• 2010

The neutral section on electric railway system is significant sector in order to prevent short circuit of two electric powers. However, while electric trains pass the neutral section, those speed is decreased and the accident of AC electric traction system and the electric train would be occurred. So the countermeasures are urgently needed. The automatic power switching technology system that is current being research and development is system to improve these problems. Because main object of this system is power change using static switch in the neutral section, it's expected to cause a variety of transients. Especially, onboard transformer inrush current for electric railway train can be occurred more than rated current according to switching time. Therefore, the analysis and improvement are needed to ensure the stability of this system. In this paper, we analyze the operating characteristics of the automatic power switching technology system. Especially, it reviews inrush current according to the closing phase angle. And we propose control plan of inrush current considering the case that voltage is maintained due to counter electromotive force and regenerative braking operation of electric railway train. Finally, the proposed control scheme was reviewed using the transient analysis program.

• 제어로봇시스템학회논문지
• /
• 제14권5호
• /
• pp.411-414
• /
• 2008

OPC is the preferred communication standard for sharing process control data at all levels of the enterprise and becomes the global standard, sends/receives the data with PLC programs of inspection system via network, and manages various data using OPC server. In this paper, we introduce the developed OPC client system for FPD inspection system with OPC server. To control inspection system through OPC server, we have developed libraries which consist of stage driver, switch driver, microscope driver, image processing, alignment, and task management modules. Also we have developed the test program to verify all functions precisely. We describe the mechanism of inspection system, OPC connection method, and programs.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1998년도 하계학술대회 논문집 B
• /
• pp.585-587
• /
• 1998

It is suggested that the PWM inverter is controlled by Digital Software Programming. VVVF(Variable Voltage Variable Frequency) inverter control being used by PWM control for driving the motor with speed-varying, makes the PWM pattern with calculating the output voltage and frequency, and with controlling the carrier and signal, so actually this method is difficult to correspond with driving the motor by using voltage-varying and frequency-varying. Therefore this research suggested the new algorithm controlled by micro processor which is already stored by various PWM form of output voltage by using fundamental data of the carrier and signal. The PWM wave can be controlled with real time by using extra hardware and digital software and to speed up program processing, the control signals to switch the power semi-conductor of three phase PWM inverter, simultaneously use the output signal by microprocessor and extra hardware, and control signal by software. In the end, this method was proved by applying to Three Phase Voltage-type Inverter.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 A
• /
• pp.76-78
• /
• 2000

The previous MCC's have the demerits of high cost and much manhour for rework because they are impossible for the standardization of products and have many manual connections. The customers require the products which can operate in connection with SCADA system by digitalizing the functions of the current MCC's and are systematized with capability of remote control. To solve these disadvantages and requirements, we developed the Electronic Motor Control System according to starting type for applying to fields based on this. This system has the various functions such as protection, measurement, and communication. Using these functions, it can monitor motor status through communication with the upper system and define the circuit for lower connection cost according to starting type and shorter manufacture period by program. The development of this product results in establishment of competitive structure with domestic competition and perfect automatic monitoring through linkage with SCADA system. In addition, it provides the comparable dominancy of receiving on orders in switch gear and adaptability to change of MCC market in Japan and Europe.

• 대한전기학회논문지
• /
• 제45권1호
• /
• pp.67-73
• /
• 1996

Subsynchronous resonance(SSR) causes a torsional shaft torque on the generator. Damages resulting from the uncontrolled SSR have resulted in the breakdown in the shaft and costs for replacement power. This paper is to determine the feasibility of controlling SSR by the fast modulation of series compensation capacitors. The presence of subsynchronous currents in the system was detected by a subsynchronous relay which was modeled by the transient analysis of control systems(TACS) in electromagnetic transients program (EMTP). The capacitor segments were switched by bi-directional thyristor switches. These were modeled into EMTP. The strategy to switch the capacitors were modeled as a closed loop system. The paper proves that effective control of SSR can be obtained only by the detuning of the system and the removal or blocking of subsynchronous energy from the system. (author). refs., figs., tabs.

• International journal of advanced smart convergence
• /
• 제5권3호
• /
• pp.16-26
• /
• 2016

This proposed project is about a bicycle anti theft devised system which helps people protect the bicycle from theft and helps to track the stolen bicycle's location using a smart phone. Safety bike uses two main devices to keep the bicycle secured, the vibration sensor and GPS sensor. The purpose of this project is to put all these small devices into one well connected system which will help the bicycle owner have more control over the security of his own bicycle. The whole system can be divided into two main parts. The first part is about the hardware development whereby all electronics components are connected via the circuit design using wire wrapping technique. This hardware part includes, a vibrations sensor, a GPS receiver, a toggle switch, LED light, Bluetooth and a buzzer. Wireless Bluetooth signals are used as the means of communication between the smartphone and the microcontroller. The second part is the software part which is being to program and control the whole system. The program is written using MikroBasic, a full-featured Basic compiler for microcontroller based systems. In conclusion, this system is designed to enable user to have control in securing his/her bicycle also being able to find and locate it at any time using GPS receiver and mobile android application.

• 대한전기학회논문지:전력기술부문A
• /
• 제53권1호
• /
• pp.13-21
• /
• 2004

In the design of superconducting cable systems, quench analysis have to be advanced for applying to a real systems. It is necessary to calculate the current, voltage and resistance during the quench. Simulation program named EMTDC was used to analyze the quench state. Normal zone evaluation and quench development with EMTDC are one of the major features of quench analysis. This paper presents the two kinds of quench control models which are the Switch Control Type and the Fortran Control Type. In case of the quench developing area, the simplicity cable model consist of resistance, inductance and capacitance. The impedance of the pipe type superconducting cable is calculated by numerical analysis method. The resistance and inductance increased during quench. However the variation have an effect on the fault current. The voltage was also developed by resistance and inductance. This paper presents the relationship between the current. voltage, resistance and inductance during quench.