• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.512-512
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• 2000

In this article, a current mode peak detector circuit is presented. The simple circuit configuration comprises four MOS transistors and one external capacitor. The realization method is suitable fur fabrication using CMOS technology and all transistors are operated in their saturation region. The proposed circuit exhibits a very low drop rate and provides high accuracy, high-speed and wide dynamic range. The proposed circuit has very low power dissipation and operates using a single 2.5V supply. Simulation results confirmed the characteristic of the proposed circuit are also included.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.340-342
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• 2005

A sliding mode controller for the grid-connected photovoltaic system has been presented. This controller is constructed from the time-varying sliding surface In order to control the sinusoidal inductor current and solar array power simultaneously. The proposed controller can achieve the tight regulation of current and power under the parameter variation environment.

• Proceedings of the KIEE Conference
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• 2001.10a
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• pp.239-241
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• 2001

Recently the power supply equipments have tendency to take multiple feedback loop paths. In this paper, the state space averaging technique is applied for the analysis of flyback type current mode control circuit. We made real converter for the gurantee of stable output characteristic and proper design of feedback circuit. The validity of proposed method is verified from test results. The improvement of stability is confirmed by sinusoidal signal injection method with isolated transformer. It is known that phase margin is sufficient and gain crossover frequency $f_c$, is nearly 1/5 of switching frequency $f_s$, from the experimental result with frequency response analyzer.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1082-1089
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• 2017

Negative output elementary super lift Luo converter (NOESLLC), which has the significant advantages including high-voltage transfer gain, high efficiency, high power density, and reduced output voltage/inductor current ripples when compared to the traditional DC-DC converters, is an attractive DC-DC converter for the field of negative DC voltage applications. In this study, in consideration of the voltage across the energy transferring capacitor changing abruptly at the beginning of each switching cycle, the improved averaged model of the NOESLLC operating in continuous conduction mode (CCM) is established. The improved DC model and transfer functions of the system are derived and analyzed. The current mode control is applied for this NOESLLC. The results from the theoretical calculations, the PSIM simulations and the circuit experiments show that the improved DC model and transfer functions here are more effective than the existed ones of the NOESLLC to describe its real dynamical behaviors.

• Proceedings of the KIEE Conference
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• summer
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• pp.1214-1216
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• 2004

Conventional Switched Mode Power Supplies(SMPS) with diode-capacitor rectifier have distorted input current waveform with high harmonic contents. Typically, these SMPS have a power factor lower than 0,65. To improve with this problem the power factor correction(PFC) circuit of power supplies has to be introduced. PFC circuit have tendency to be applied in new power supply designs. The input active power factor correction circuits can be implemented using either the two-stage or the single-stage approach. In this paper, the comparative analysis of power factor correction circuit using feedforward control with average current mode single-stage flyback method converter and two-stage converter which is combination of boost and flyback converter. The two prototypes of 50W were designed and tested a laboratory experimental. Also, the comparative analysis is confirmed by simulation and experimental results.

• Journal of Power Electronics
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• v.11 no.5
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• pp.655-661
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• 2011

This paper presents two topologies for single-stage single-phase double-buck type PFC converters, designed to operate at high power factor, near sinusoidal input currents and adjustable output voltage. Unlike the known buck type PFC topologies, in which the output voltage is always lower than the maximum input voltage, the proposed converters can operate at output voltages higher than the ac input peak voltage. A reduced number of switches on the main path of the current are another characteristic of the two proposed topologies. To shape the input line currents, a fast and robust controller based on a sliding mode approach is proposed. This active non-linear control strategy, applied to these converters allows high quality input currents. A Proportional Integral (PI) controller is adopted to regulate the output voltage of the converters. This external voltage controller modulates the amplitude of the sinusoidal input current references. The performances of the presented rectifiers are verified with experimental results.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3190-3192
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• 1999

A Novel wide-band wide-tunable current-mode (CM) gamma corrector for HDTV camera applications is proposed. The gamma corrector provides accurate gamma control in a wide range by simple electrical adjustment of weighting amplifiers' gain. It has wide signal bandwidth more than 40MHz sufficient for HDTV video signal processing and is implementable with simple integrated circuit with low power dissipation of 125mW.

• Proceedings of the KIEE Conference
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• 1996.11a
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• pp.363-366
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• 1996

A FB-ZVS(Full Bridge Zero Voltage Switching) PWM DC/DC converter for electric vehicles is simulated and implemented in this paper. The converter considered is a step-down DC/DC converter with the ratings of 312/13.5V and 1.35kW. The steady state operation of this converter is divided into six operating modes in case of continuous current mode and eight operating modes in case of discontinuous current mode. Digital simulations using PSpice are carried out to verify the steady-state analysis. A prototype converter was built in the laboratory. MOSFETs were used for swithching devices and fast recovery diodes to reduce the charge storage problem of a pn-junction.

• Proceedings of the KIEE Conference
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• 2000.11b
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• pp.365-367
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• 2000

Recently, the power supply equipments have tendency to take multiple feedback loop paths. In this paper, the state space averaging technique is applied for the analysis of flyback type current mode control circuit. We made real converter for the gurantee of stable output characteristic and proper design of feedback circuit. The validity of proposed method is verified from test results. The improvement of stability is confirmed by sinusoidal signal injection method with isolated transformer. It is known that phase margin is sufficient and gain crossover frequency $f_c$ is nearly 1/5 of switching frequency $f_s$ from the experimental result with frequency response analyzer.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.357-358
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• 2014

본 논문에서는 태양광 모듈의 최대 전력점을 추종하기 위한 제어 기법으로 부스트 컨버터(boost converter)의 불연속 전류모드(Discontinuous Current Mode)에서 주파수를 제어하는 기법을 구현 하였다. 태양광 모듈에 연결된 부스트 컨버터는 전압루프를 통하여 Perturb and Observation(P&O)기법을 사용하여 최대 전력점을 추종하였다. 부스트 컨버터의 인덕터에 흐르는 전류는 불연속 전류모드로 제어 된다. 불연속 전류모드에서의 제어기 설계는 MATLAB과 PSIM의 전달함수특성을 수학적 모델링을 통하여 비교 검증 하였으며, 모든제어는 MCU(TEXAS INSTRUMENTS사의 DSPF28335)를 통해 디지털로 제어 하였다. 제안된 기법은 단일 PV모듈이 연결된 불연속전류모드 부스트 컨버터를 통해 동작특성을 분석하였다.