• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 추계학술대회
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• pp.3-4
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• 2011

This paper presents a survey of floating power supply based on bootstrap operation for three-level voltage-source inverters. The floating power supply for upper switches is achieved by the bootstrap capacitor charged during on-time of the switch underneath. Hence, a large number of bulky isolated DC/DC power supplies for each gate driver are reduced. The Pspice simulation results show the behavior of bootstrap devices and the performance of bootstrap capacitor voltage.

• Journal of Power Electronics
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• 제17권5호
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• pp.1382-1390
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• 2017

This paper presents a power supply for gate drivers, which uses a magnetic resonance wireless power transfer system. Unlike other methods where multiple antennas are used to supply power for the gate drivers, the proposed method uses a single antenna in an insulated receiver to make multiple mutually isolated power supplies. The power transmitted via single antenna is distributed to multiple power supplies for gate drivers through resonant capacitors connected in parallel that also block DC bias. This approach has many advantages over other methods, where each gate driver needs to be supplied with power using multiple receiver antennas. The proposed method will therefore lead to a reduction in production costs and circuit area. Because the proposed circuit uses a high resonance frequency of 6.78 MHz, it is possible to implement a transmitter and a receiver using a small-sized spiral printed-circuit-board-type antenna. This paper used a single phase-leg circuit configuration to experimentally verify the performance characteristics of the proposed method.

• 전력전자학회논문지
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• 제26권6호
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• pp.429-436
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• 2021

The design of a gate driver power supply for a three-phase inverter using a silicon carbide (SiC) MOSFET. The requirements for the power supply circuit of the gate driver for the SiC MOSFET are investigated, and a flyback converter using multiple transformers is used to make the four isolated power supplies. The proposed method has the advantage of easily constructing the power supply circuit in a limited space as compared with a multi-output flyback converter using a single core. The power supply circuit for the three-phase SiC MOSFET inverter for driving an AC motor is designed and implemented. The operation and validity of the implemented circuit are verified through simulations and experiments.

• Journal of Electrical Engineering and Technology
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• 제12권1호
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• pp.486-493
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• 2017

Refineries and chemical plants with isolated power systems that have a limited power supply are more susceptible to voltage changes from disturbances compared to power systems connected with a power company. Furthermore, most loads in such cases are induction motor loads, and therefore, transient voltage characteristics when starting a high-capacity motor must be examined. In general, high-capacity motors are customized appropriately to the load performance curve by the manufacturer during the construction of an industrial plant. Subsequently, when complying with the voltage drop permitted by international standards during the design process, power supply equipment such as transformers and generators is overdesigned. Therefore, a novel analysis is necessary on standards for startup and constraint voltage drops, as well as on identifying the voltage drop limitations for starting high-capacity motors in refineries and chemical plants with isolated power systems. In this study, field tests on an industrial plant were conducted, and simulations modeled under conditions identical to those of the field test system were performed using the general-purpose program ETAP in order to compare the results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.3-11
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• 2002

This paper presents the trend of low voltage and high current technology for DC-DC converters. It can be said that the output voltage of the on-board power supply has been rapidly moving forward a low voltage in proportion to the minuteness of the semiconductors. As for as its speed is concerned, the change of the market situation seems to be faster than that of R&D for the low voltage and high current products put out by power supply manufacturers. Here, the present situation and the trend of non-isolated type step-down DC-DC converter and isolated type DC-DC converter called "Brick" will be taken up mainly from the fellowing point of view. -low voltage and high current keeping up with the current demand for the latest telecommunication networks and broadband. -build-up of the total solution for dispersion system power supply. In this paper, an explanation is given to mainly concerning to the newest products in the supplier's position.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.430-432
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• 2005

This paper presents a novel, single stage, isolated, three-phase switching rectifier capable of switching at high frequency. The circuit topology Provides zero-voltage switching for all switches, output voltage regulation, unity input power factor, all in a single power conversion stage. Operating principle and experimental results in the 48V/100A DC power supply of three-phase single stage method are presented.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2017년도 전력전자학술대회
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• pp.355-356
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• 2017

In this paper, a highly isolated DC-DC converter is designed as a power supply, and an insulator-molded transformer is used to achieve high insulation performance. Finally, the insulation performance of the power supply was verified by experimental results.

• 한국산업융합학회 논문집
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• 제25권4_1호
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• pp.493-504
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• 2022

Recently, as interest in eco-friendliness grows, the supply of hybrid electric vehicles and pure electric vehicles (EVs) for improving fuel efficiency of automobiles is rapidly expanding. The average daily energy consumption of electric vehicles is less than 20 [%] of the total ESS capacity of the vehicle, and research on additional functions using the ESS of the vehicle is urgently needed to expand the supply of electric vehicles. V2H(Vehicle to Home), like V2G(Vehicle to Grid), includes the concept of cooperating with system stabilization using ESS of electric vehicles. In addition, it includes various operations that can realize home welfare, such as uninterrupted power supply in case of power outage at home, and power supply for home DC devices. Therefore, in order to expand the supply of eco-friendly electric vehicles, it is urgently required to develop a V2H system with various functions that can realize home welfare. In this paper, we propose a V2H system with a CLLC resonant converter and a non-isolated step-up converter that can solve different impedance and resonant frequencies depending on the power transfer direction. The proposed V2H system is 6 [kVA] applicable to 150-450 [V], the voltage range that can use the ESS voltage for electric vehicles, and is designed with a capacity that can handle instantaneous electricity use at home. In addition, in order to verify the feasibility, an experiment by Psim simulation and prototype production was performed.

• 전력전자학회논문지
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• 제20권1호
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• pp.11-18
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• 2015

This paper proposes a high-efficiency 3-kW hybrid ESS with emergency power supply. The proposed system enables efficient use of power from photovoltaic (PV) cells and energy storage system (ESS). The proposed system can operate as an uninterruptible power supply (UPS) when grid fault occurs, providing seamless transfer from grid-connected mode to stand-alone mode. The LLC converter for PV achieves ZVS turn-on of switches and ZCS turn-off of diodes, and the isolated bidirectional DC-DC converter for ESS achieves ZCS turn-off regardless of load condition, resulting in high efficiency. The efficiency and performance of the proposed hybrid ESS has been verified by a 3-kW prototype.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.902-904
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• 2005

The AC-DC converter, which has three-phase AC power as input and isolated DC power as output is used for the regulated DC power supply of the telecommunication power processing system for several kilowatt class applications. The conventional DC power supply for the telecommunication power system comprises a PWM rectifier with sine-wave shaping input current unity power factor and a DC/DC converter connected to the PWM converter, which obtains DC 48[V]. Since power passes through these two power stage converters, the conversion power loss is difficult to provide high efficiency. To resolve these problems, this paper presents a new PWM rectified as a 1-stage power conversion method. It simulation and experimental results as proved from a practical point of view that 92.1[%]of conversion efficiency and input current which can meet harmonics regulation of the Class-A in IEC61000-3-3 are achieved.