• Journal of Power Electronics
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• v.16 no.5
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• pp.1689-1697
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• 2016

Continuous conduction mode (CCM) boost converters are commonly used in home appliances and various industries because of their simple topology and low input current ripples. However, these converters suffer from several disadvantages, such as hard switching of the active switch and reverse recovery problems of the output diode. These disadvantages increase voltage stresses across the switch and output diode and thus contribute to switching losses and electromagnetic interference. A new topology is presented in this work to improve the switching characteristics of CCM boost converters. Zero-current turn-on and zero-voltage turn-off are achieved for the active switches. The reverse-recovery current is reduced by soft turning-off the output diode. In addition, an input current sensorless control is applied to the proposed topology by pre-calculating the duty cycles of the active switches. Power factor correction is thus achieved with less effort than that required in the traditional method. Simulation and experimental results verify the soft-switching characteristics of the proposed topology and the effectiveness of the proposed input current sensorless control.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.3
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• pp.243-249
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• 2001

This paper proposes a full wave mode ZVT-PWM boost converter. The converter with the auxiliary switch in a full wave mode makes possible soft switching operation of all switches including the auxiliary switch whereas the auxiliary switch is turned off with hard switching in the conventional converter. Therefore, the proposed converter reduces the turn-off switching loss and switching noise of the auxiliary switch without additional passive and/or active elements and high power density system can be realized.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.346-347
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• 2011

본 논문에서는 정전류 LED조명 구동을 위한 일차측 전류 제어의 새로운 기법을 제안한다. 일정한 온-타임으로 동작하는 경계 모드(Critical Mode) 플라이백 타입으로 우수한 역률을 달성하였고, 의사 공진(Quasi-resonant) 동작으로 스위칭 손실을 최소화 하였다. 본문에서 LED전류가 5% 이하로 정전류 제어되는 9W급 플라이백 타입의 일차 측 전류 제어 기법을 실험으로 검증한다.

• Journal of Power Electronics
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• v.4 no.4
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• pp.246-255
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• 2004

Ac-dc PWM single-stage converters that integrate the PFC and dc-dc conversion functions in a single switching converter have been proposed to try to minimize the cost and complexity associated with implementing two separate and independent switch-mode converters. In this paper, two simple ac-dc single-stage PWM full-bridge converters are considered - one current-fed, the other voltage-fed. The operation of both converters is explained and their properties are noted. Experimental results obtained from simple lab prototypes of both converters are presented, then compared and discussed.

• Journal of Power Electronics
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• v.2 no.2
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• pp.139-145
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• 2002

Because conventional switching converters have been usually using unbalanced circuit topologies, parasitice between the drain/collertor of an active switch and frame ground through its heat sink may generate the commom-mode conducted noise. We have proposed a balanced switching converter circuit, whitch is an effective way to reduce the commom-mode converter version of the balanced switching converter was presented and the mechanism of the commom-mode noise reduction was explained using equivalent circuits. This paper extends the concept of the balanced switch converter circuit and presents a buck-boost converter version of the blanced switching converter. The feature of common-mode niose reduction is confirmed by experimental resuits and the mechanisem of the commom-mode niose reduction is explained using equivalent circuits.

• Journal of Power Electronics
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• v.6 no.4
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• pp.356-365
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• 2006

This paper presents an improved three-phase PFC power rectifier with a three-phase diode rectifier cascaded four-switch boost converter. Its operating principle contains the operating principle of two conventional three-phase PFC power rectifiers: one switch boost converter type and a two switch boost converter type. The operating characteristics of the four switch boost converter type three-phase PFC power rectifier are evaluated from a practical point of view, being compared with one switch boost converter type and two switch boost converter topologies.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2112-2114
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• 1998

A gate driver suitable for forced switch-mode power converters such as UPS and motor drive system is presented. The proposed gate driver uses regenerated snubber power and requires no separate power supply. This does not impose any additional complexity on the main switch. Experimental results show that the proposed circuit is valid.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.869-872
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• 2005

In this paper we present a switch wrapper for an AMBA AXI, which is an efficient on-chip-network interface compared to bus-based interfaces in a multiprocessor SoC. The AXI uses an idea of NoC to provide the increasing demands on communication bandwidth within a single chip. A switch wrapper for AXI is located between a interconnection network and two IPs connecting them together. It carries out a mode of routing to interconnection network and executes protocol conversions to provide compatibility in IP reuse. A switch wrapper consists of a direct router, AHB-AXI converters, interface modules and a controller modules. We propose the design of a all-in-one type switch wrapper.

• Journal of Power Electronics
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• v.13 no.1
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• pp.104-112
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• 2013

This paper presents a comparative evaluation of various topologies for three-phase power converters using the hardware-in-the-loop (HIL) simulation technique. Various switch-mode AC-DC power converters are studied, and their performance with respect to total harmonic distortion (THD), efficiency, power factor and losses are analyzed. The HIL-simulation is implemented in an Altera Cyclone II DE2 Field Programmable Gate Array (FPGA) Board and in the Matlab/Simulink environment. A comparison of the simulation and HIL-simulation results is also provided.

• Journal of Power Electronics
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• v.15 no.1
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• pp.131-145
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• 2015

The voltage-source inverters (VSI) supplying a motor drive are prone to open transistor faults. To address this issue in fault-tolerant drives applicable to electric vehicles, a new open transistor fault diagnosis (FD) method is presented in this paper. According to the proposed method, in order to define the FD index, the phase angle of the converter output current is estimated by a simple trigonometric function. The proposed FD method is adaptable, simple, capable of detecting multiple open switch faults and robust to load operational variations. Keeping the FD in mind as a mandatory part of the fault tolerant control algorithm, the FD block is applied to a five-phase converter supplying a multiphase fault-tolerant PM motor drive with non-sinusoidal unbalanced current waveforms. To investigate the performance of the FD technique, the fault-tolerant sliding mode control (SMC) of a five-phase brushless direct current (BLDC) motor is developed in this paper with the embedded FD block. Once the theory is explained, experimental waveforms are obtained from a five-phase BLDC motor to show the effectiveness of the proposed FD method. The FD algorithm is implemented on a field programmable gate array (FPGA).