• Proceedings of the KIEE Conference
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• 2002.04a
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• pp.139-142
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• 2002

A resonant type voltage source and power device and a control method using Pulse Density Modulation(PDM) power control and Pulse Width Modulation(PWM) voltage control for Ozone Generator are described. For the stability of discharge in the generating tube, it is desirable that the peak apply voltage is constant. The PDM power control is employed for sustaining the voltage constant at any generating tube input power. Moreover, to avoid the influence of input AC voltage fluctuation etc., PWM voltage control with generating tube peak voltage feedback is used. Both functions were confirmed by the experiment with 6.5[kHz], 1.8[kW] inverter and generating tube. The effect of input synchronous PDM method for input current stabilizing is confirmed also.

• Proceedings of the KIEE Conference
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• 2002.06a
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• pp.52-54
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• 2002

A resonant type voltage source and power device and a control method using Pulse Density Modulation(PDM) power control and Pulse Width Modulation(PWM) voltage control for plasma sterilization are described, For the stability of discharge in the generating tube, it is desirable that the peak apply voltage is constant. The PDM power control is employed for sustaining the voltage constant at any generating tube input power. Moreover, to avoid the influence of input AC voltage fluctuation etc.. PWM voltage control with generating tube peak voltage feedback is used. Both functions were confirmed by the experiment with 6.5[kHz], 1.8[kW] inverter and generating tube. The effect of input synchronous PDM method for input current stabilizing is confirmed also.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1172-1174
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• 2003

A resonant type voltage source and power device and a control method using Pulse Density Modulation(PDM) power control and Pulse Width Modulation(PWM)voltage control for plasma sterilization are described. For the stability of discharge in the generating tube, it is desirable that the peak apply voltage is constant. The PDM power control is employed for sustaining the voltage constant at any generating tube input power. Moreover, to avoid the influence of input AC voltage fluctuation etc., PWM voltage control with generating tube peak voltage feedback is used. Both functions were confirmed by the experiment with inverter and generating tube. The effect of input synchronous PDM method for input current stabilizing is confirmed also.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.397-401
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• 2003

A resonant type voltage source and power device and a control method using Pulse Density Modulation(PDM) power control and Pulse Width Modulation(PWM) voltage control for plasma sterilization are described. For the stability of discharge in the generating tube, it is desirable that the peak apply voltage is constant The PDM power control is employed for sustaining the voltage constant at any generating tube input power. Moreover, to avoid the influence of input AC voltage fluctuation etc., PWM voltage control with generating tube peak voltage feedback is used. Both functions were confirmed by the experiment with 6.5[㎑], 1.8[㎾] inverter and generating tube. The effect of input synchronous PDM method for input current stabilizing is confirmed also.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.613-615
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• 1996

Harmonic elimination method of using coupling transformer in twelve pulse inverter is presented for high power application. This method is using coupling transformer and PWM(pulse width modulation) switching and voltage source inverter. The object of proposed harmonic elimination method is obtained inverter output of low THD(Total Harmonic Distortion). The simulation results confirm the proposed harmonic elimination method.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.847-850
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• 1998

One of the most difficult problem of designing VLSI is a mixed-circuit design, that is to design circuit containing both analog parts and digital parts. Digital to analog converter and analog to digital converter is a typical case. Especially it can be a serious problem when mixed circuit are put into a large digital circuit like microcontroller. However nowadays this problem is settled by separating analog circuit parts outside the IC. This technique is based on converting a digital signal into a pulse sequence. Then an analog signal is obtained by averaging this pulse sequence at the external low-pass filter. An anlog to digital converter is designed using a stochastic logic instead of a traditional PWM (pulse-width modulation) signal and ins implemente dusing FPGa. Stochastic pulse sequence can be made as a simple circuits and moreover can be mathematically processed by simple circuits -AND gates. The spectral property of stochastic pulse sequence method is better than that of PWM method. So it make easy to design a external low-pass filter. This technique has important advantages, especially the reduction of the ADC cost.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1012-1017
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• 2003

The development of a fast, accurate, and inexpensive position-controlled pneumatic actuator that may be applied to a variety of practical positioning applications with various external loads is described in this paper. A novel modified pulso width modulation (MPWM) valve pulsing algorithm allows on/off solenoid valves to be used in place of costly servo valves. A comparison between the system response of standard PWM technique and that of the novel modified PWM technique shows that the control performance is significantly increased. A state feedback controller with position, velocity and acceleration feedback is successfully implemented as the continuous controller. Switching algorithm of control parameter using learning vector quantization neural network (LVQNN) is newly proposed. which estimates the external loads of the pneumatic actuator. The effectiveness of the proposed control algorithms are demonstrated through experiments with various loads.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.751-753
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• 1999

In this paper, a simple SR method of AC motor has introduced. The method achived by appling the Pulse-Width Modulation(PWM) method to control the ON and OFF time of motor. The method is simple, practicable and has no problem of shift and out of control which is existed in SR method of SCR.

• Proceedings of the KIPE Conference
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• 2016.11a
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• pp.230-231
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• 2016

본 논문은 공간벡터 변조 방법에서부터 Six-step 동작까지의 새로운 과변조 방법을 제시하였다. 극전압을 푸리에 시리즈를 이용하여 분석하였고 지령 상전압에서부터 펄스 폭 변조 스위칭 신호까지의 알고리즘을 제안하였다. Matlab 시뮬레이션을 통해 검증하였다.

• Journal of Power Electronics
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• v.12 no.6
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• pp.886-894
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• 2012

This paper presents a secondary-side, dual-mode feedback LLC resonant controller IC with dynamic PWM dimming for LED backlight units. In order to reduce the cost, master and slave outputs can be generated simultaneously with a single LLC resonant core based on dual-mode feedback topologies. Pulse Frequency Modulation (PFM) and Pulse Width Modulation (PWM) schemes are used for the master stage and slave stage, respectively. In order to guarantee the correct dual feedback operation, Phased-Locked Loop (PLL)-based automatic duty control circuit is proposed in this paper. The chip is fabricated using $0.35{\mu}m$ Bipolar-CMOS-DMOS (BCD) technology, and the die size is $2.5mm{\times}2.5mm$. The frequency of the gate driver (GDA/GDB) in the clock generator ranges from 50 to 425 kHz. The current consumption of the LLC resonant controller IC is 40 mA for a 100 kHz operation frequency using a 15 V supply. The duty ratio of the slave stage can be controlled from 40% to 60% independent of the frequency of the master stage.