• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2008년도 제39회 하계학술대회
• /
• pp.1184-1185
• /
• 2008

The wind generation system is trend that amount used increases recently. In this paper, Introduce about development of wind force development system. This system does easily research for wind power. Compose a control program by VB so that alteration, output result deposit and waveform analysis etc. is possible and did so that all manufacturing and checkout may be available in computer.

• Journal of Advanced Marine Engineering and Technology
• /
• 제19권4호
• /
• pp.79-91
• /
• 1995

Recently, the AC motor which has a simple structure and needs less maintenance has become to be used frequently as a servomotor for position control in the automatic control field. This paper concerns with a method to improve the current and power waveforms of an AC motor, and the current waveforms and 3$\phi$ power waveforms are analyzed by FFT under verious running conditions. The system is composed of a digital bridge inverter, low pass LC filter, and 3$\phi$ AC motor. Through the computer simulations and experiments, it is confirmed that current waveforms and $\phi$ power waveforms con by improved by utilizing the high order low pass LC filter than that of lower order.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 1998년도 전력전자학술대회 논문집
• /
• pp.5-9
• /
• 1998

In the high speed rail system, the distortion of the voltage and the current waveform of the input power line increases the power loss and make a several electro-magnetic problems such as EMI or the interference of the communication line. In this paper, the control scheme of the PWM converter to make a good power factor and to regulated the output voltage as well as to reduce the harmonic component of the input current is proposed. Also a control schem of the PWM converter in the parallel operation to reduce the harmonics of the input current is proposed

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
• /
• 제53권1호
• /
• pp.16-23
• /
• 2004

Permanent magnet-excited transverse flux linear motor(TFLM) is known to have more excellent ratio of force to weight than any other linear motors. But, thrust generated by phase current is non-linear with regard to current and relative position like switched reluctance motor. This makes current and speed controller design difficult. This paper presents a method on minimization of thrust ripple of permanent magnet-excited transverse flux linear motor. Using genetic algorithm(GA), optimal current waveform can be found under the constraint conditions such as current limit, minimum of ohmic loss and limited rate of change of current etc. The effectiveness is verified through computer simulation and experimental test results.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
• /
• pp.355-357
• /
• 1999

Single-Phase multi-level AC-DC converter that is composed of diode bridge and switch is proposed. The number of the supply current level is depending on the individual current level of the converter. A converter circuit, the number of the level is equal to $2^{M+1}-1$, where M is the number of Switching Converter. The proposed circuit has converter with 31 current levels. When the number of current level is increased, smoother sinusoidal waveform can be obtained directly and it is possible to control the supply current almost continuously from zero to maximum without generating high voltage step changes as pulse with modulation technology. The technique illustrates its validity and effectiveness through the PSIM.

• 제어로봇시스템학회논문지
• /
• 제12권10호
• /
• pp.1022-1028
• /
• 2006

A portable ECG sensor module and monitoring system which has the powerline noise reduction and the baseline wander removal is proposed. A small-szie ECG sensor H/W module with the 8-bits microprocessor is implemented. The ECG waveform can be inspected anytime with PDA in real time, and transmitted to the PC through wireless LAN. Portable ECG system can offer the environment that give the lasting medical service to the elderly and the long-time hospitalized patients at the wanted place, and the system can be attached to the chair, wheel chair, treadmill, elderly walker and used to monitor the health condition of man

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
• /
• pp.527-529
• /
• 1987

This paper presents a study on the driving characteristics or delta inverter driving induction motor control systems based on the microprocessor. Delta inverter is a novel circuit which uses only three power transistor. Requiring approximately hair the components or a conventional bridge inverter it therefore has a merit of coat and Simplicity. The basic operating principles of the delta inverter and conventional bridge inverter are argued, using resistive and inductive load. Sinusoidal PWM method uses to reduce the harmonic components of its output waveform to acceptable levels.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 하계학술대회 논문집 D
• /
• pp.2559-2561
• /
• 2002

This paper presents a systematic method of probing channel characteristics and communication reliabilities of home PLC (power line communication) network applied to the Internet accessed control of home appliances. The effects of the three performance deterioating factors, i.e., additive noise, channel attenuation, and intersymbol interference, can be systematically measured by applying the channel probing waveform in the frequency range from 100kHz to 450kHz. The agreement between the derived probability of bit error and the measured probability of bit error supports the validity of the proposed approach of probing home power line channel characteristics. The experimental results performed with the constructed test-bed applying the proposed channel probing method also support the feasibility of commercially deploying the PLC modem installed home appliances and their services for the Internet accessed home automation.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 1999년도 춘계학술대회 논문집
• /
• pp.322-327
• /
• 1999

In most railway vehicle applications, a single phase AC/DC converter is used greatly and is essential equipment for Korea High Speed Train. A diode bridge rectifier and a phase-controlled thyristor bridge rectifier generate harmonics in power system. Nowadays, power factor and harmonics become major issue in electrical equipment for railway vehicle. Many researchers have been trying to improve the power factor and ac-side harmonics. Therefore the PWM converter is used to operate at unity Power factor and to reduce ac-side current harmonics. This paper describes the circuit for AC/DC PWM converter of Korea High Speed Train and proposes control algorithm to realize the sinusolidal input current waveform and the effective unity power factor. The validity of the proposed control method is verified through the experimental result.

• The Journal of Korean Physical Therapy
• /
• 제7권1호
• /
• pp.1-8
• /
• 1995

The purpose of this study was to determine the effects of high voltage pulsed current(HVPC) and low voltage pulsed current(LVPC) on posttraumatic edema formation in frog hind limbs In this study, 16 bullfrogs(Rana Catesbeiana), weighting 189g to 340g were used. Limb 16 anesthetized bullfrogs were systemically injuried by weight drop. One hind limb of each frogs was randomly selected to receive continuous 120 pps HVPC and 100 pps LVPC at $90\%$ of motor threshold(HVPC : 33.3v, LVPC : 0.2-1mA). The opposite hind was remained as a control. A series of six 30-minute treatment(interrupted by 30-minute rest) was begun minutes after injury. The results were as follows. 1. Cathodal HVPC has heed shown to be effective in curbing posttraumatic edema formation in frogs, but anodal HVPC did not effect. 2. Volumes of hind limbs treated with LVPC were not significantly different over time from those of untreated hind limbs. 3. Therefore, waveform(HVPC versus LVPC) seems to influence the efficacy of electrotherapy for edema control. 4. Electrical stimulation were not increased edema formation on frog hind limbs.