• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.165-170
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• 1998

The paper describes developed method of feedforward digital modulation of line-to-line voltage of 3-phase inverter for drive application. It is based on representation of parameters of output voltage of inverter in function of operating frequency of drive system. Pure algebraic control laws and big computational simplicity characterize this scheme of modulation. It has been presented results of simulation of adjustable drive systems with the method of pulse-width modulation described.

• Journal of the Semiconductor & Display Technology
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• v.5 no.3 s.16
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• pp.37-41
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• 2006

In this paper, a composition modulation of Dot-matrix display grayscale is presented. There's two method of expression of Dot-matrix Display grayscale. One is PWM by controlling pulse width. The other is PAM by controlling pulse amplitude. Composition modulation of Dot-matrix use PWM and PAM together. Composition modulation shows the number of grayscale as number of grayscale of PWM$\times$number of grayscale of PAM and have the effect of reduced size than existing single modulation.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.2
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• pp.117-122
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• 2009

In this paper, the performance of double binary turbo code is analyzed and simulated in ultra wide-band (UWB) systems employing multiple-antenna scheme. We consider both pulse position modulation-time hopping (PPM-TH) and pulse amplitude modulation-direct sequence (PAM-DS) UWB systems. The space time block code (STBC) scheme is adopted as a transmit diversity method. Also, receive diversity scheme is applied. And double binary turbo code is applied to the UWB system.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.4
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• pp.397-402
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• 2003

This paper concerns a pulse-width-modulation (PWM) controller design technique using digital redesign. Digital redesign is to convert a well-designed analog controller into an equivalent pulse-amplitude-modulation (PAM) controller maintaining the original analog control system in the sense of state-matching. In similar line of conversion concept, the redesigned PAM controller is converted into a PWM controller using the equivalent area principle. To convincingly visualize the proposed technique, an computer simulation example-attitude control of artificial satellite system is included.

• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.6
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• pp.441-448
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• 2007

To enhance the competitive edge of the material cost, IP(Integrated Power) Board form of inverter circuit is widely used in large area LCD TV(Greater than or equal to 40 in.). This scheme is Two Stage System and one inverter drives multi-lamp in a parallel circuit. This paper analyzes the conventional IP Board inverter controlled with Pulse Width Modulation (PWM), and its problems such as serious hard switching and excessive circulating energy can be solved by a proposed Pulse Count Modulation (PCM) scheme. To confirm the validity and superiority of the proposed system, theoretical analysis and experimental results are presented.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.6
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• pp.726-731
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• 2004

This paper proposes a pulse-width-modulation (PWM) controller design technique using intelligent digital redesign. Intelligent digital redesign is to convert a well-designed analog fuzzy-model-based controller into an equivalent pulse-amplitude-modulation (PAM) digital controller maintaining the original analog control system in the sense of state-matching. In similar line of conversion concept, the redesigned PAM intelligent digital controller is converted into a PWM controller using the equivalent area principle. To convincingly visualize the proposed technique, an computer simulation example-attitude control of nonlinear artificial satellite system is included.

• The Transactions of the Korean Institute of Power Electronics
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• v.5 no.2
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• pp.192-199
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• 2000

This paper describes a Phase-Shift Pulse Modulation(PSPM) and Frequency Trad이ng Pulse Modulation(FTPM) s series resonant high-frequency inverter using IGBT for the power control of high-frequency induction heating u using Neuro-Fuzzy, which is practically applied for 20kHz~500kHz induction-heating and melting power supply in i indust껴aJ fields. The adaptive frequency tracking based on the PSPM(phase-shifting pulse modulation) r regulation scherne is presented in or$\tau$ler to l11lmmlZe svvitching losses. The trially-produced breadboards using N Neuro Fuzzy controller are successfully demonstrated cUld cliscussed.

• Journal of Power Electronics
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• v.13 no.4
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• pp.619-625
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• 2013

Switched mode power supplies (SMPS) are power electronic circuits extensively used in a wide range of applications. High frequency switching operation of SMPS causes electromagnetic emissions and has the potential to interfere with system operation, which in turn has an impact on system performance. This makes electromagnetic compatibility (EMC) an important concern. In this paper, a new and simple spread spectrum technique is proposed by modulating chaotic pulse position modulation (CPPM) and pulse width modulation (PWM). The resulting CPWM is implemented to reduce the conducted EMI in SMPS. The proposed method is found to be effective in reducing conduction EMI. The effectiveness and simplicity of the proposed method on spreading those dominating frequencies is compared to the EMI mitigation technique using an external chaotic generator. Finally, the levels of conductive EMI with standard PWM, CPWM with an external chaos generator and the proposed method are experimentally verified to comply with the CISPR 22A regulations. The results confirm the effectiveness of the proposed method.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.3
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• pp.179-184
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• 2010

In this paper, we analyze and simulate the performance of RAKE receiver for ultra wide band (UWB) systems in indoor multipath radio channel. Pulse position modulation-time hopping (PPM-TH) signal is considered. And we also consider three types of RAKE receivers, which are ideal RAKE, selective RAKE, and partial RAKE receivers. The indoor channel is modeled as the modified Saleh and Valenzuela (SV) model which has been proposed as a UWB channel model by the IEEE group, IEEE 802.15.SG3a.

• Journal of Power Electronics
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• v.15 no.1
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• pp.65-77
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• 2015

Resonant converters are well suited for induction heating (IH) applications due to their advantages such as efficiency and power density. The control systems of these appliances should provide smooth and wide power control with fewer losses. In this paper, a simple phase locked loop (PLL) based variable duty cycle (VDC) pulse density modulation (PDM) power control scheme for use in class-D inverters for IH loads is proposed. This VDC PDM control method provides a wide power control range. This control scheme also achieves stable and efficient Zero-Voltage-Switching (ZVS) operation over a wide load range. Analysis and modeling of an IH load is done to perform a time domain simulation. The design and output power analysis of a class-D inverter are done for both the conventional pulse width modulation (PWM) and the proposed PLL based VDC PDM methods. The control principles of the proposed method are described in detail. The validity of the proposed control scheme is verified through MATLAB simulations. The PLL loop maintains operation closer to the resonant frequency irrespective of variations in the load parameters. The proposed control scheme provides a linear output power variation to simplify the control logic. A prototype of the class-D inverter system is implemented to validate the simulation results.