A Novel type of High-Frequency Transformer Linked Soft-Switching PWM DC-DC Power Converter for Large Current Applications

Keiki Morimoto,Nabil A. Ahmed,Hyun-Woo Lee,Mutsuo Nakaoka 대한전기학회 2006 Journal of Electrical Engineering & Technology Vol.1 No.2

This paper presents a new circuit topology of DC busline switch and snubbing capacitor-assisted full-bridge soft-switching PWM inverter type DC-DC power converter with a high frequency link for low voltage large current applications as DC feeding systems, telecommunication power plants, automotive DC bus converters, plasma generator, electro plating plants, fuel cell interfaced power conditioner and arc welding power supplies. The proposed power converter circuit is based upon a voltage source-fed H type full-bridge high frequency PWM inverter with a high frequency transformer link. The conventional type high frequency inverter circuit is modified by adding a single power semiconductor switching device in series with DC rail and snubbing lossless capacitor in parallel with the inverter bridge legs. All the active power switches in the full-bridge inverter arms and DC busline can achieve ZVS/ZVT tum-off and ZCS turn-on commutation operation. Therefore, the total switching losses at turn-off and turn-on switching transitions of these power semiconductor devices can be reduced even in the high switching frequency bands ranging from 20 ㎑ to 100 ㎑. The switching frequency of this DC-DC power converter using IGBT power modules is selected to be 60 ㎑. It is proved experimentally by the power loss analysis that the more the switching frequency increases, the more the proposed DC-DC converter can achieve high performance, lighter in weight, lower power losses and miniaturization in size as compared to the conventional hard switching one. The principle of operation, operation modes, practical and inherent effectiveness of this novel DC-DC power converter topology is proved for a low voltage and large current DC-DC power supplies of arc welder applications in industry.

DC Rail Side Series Switch and Parallel Capacitor Snubber-Assisted Edge Resonant Soft-Switching PWM DC-DC Converter with High-Frequency Transformer Link

Keiki Morimoto,Khairy Fathy,Hiroyuki Ogiwara,Hyun Woo Lee,Mutsuo Nakaoka 전력전자학회 2007 JOURNAL OF POWER ELECTRONICS Vol.7 No.3

This paper presents a novel circuit topology of a DC busline series switch and parallel snubbing capacitor-assisted soft-switching PWM full-bridge inverter type DC-DC power converter with a high frequency planar transformer link, which is newly developed for high performance arc welding machines in industry. The proposed DC-DC power converter circuit is based upon a voltage source-fed H type full-bridge soft-switching PWM inverter with a high frequency transformer. This DC-DC power converter has a single power semiconductor switching device in series with an input DC low side rail and lossless snubbing capacitor in parallel with the inverter bridge legs. All the active power switches in the full-bridge arms and DC busline can achieve ZCS turn-on and ZVS turn-off transition commutation. Consequently, the total switching power losses occurred at turn-off switching transition of these power semiconductor devices; IGBTs can be reduced even in higher switching frequency bands ranging from 20 kHz to 100 kHz. The switching frequency of this DC-DC power converter using IGBT power modules can be realized at 60 kHz. It is proved experimentally by power loss analysis that the more the switching frequency increases, the more the proposed DC-DC power converter can achieve a higher control response performance and size miniaturization. The practical and inherent effectiveness of the new DC-DC converter topology proposed here is actually confirmed for low voltage and large current DC-DC power supplies (32V, 300A) for TIG arc welding applications in industry.

A Novel type of High-Frequency Transformer Linked Soft-Switching PWM DC-DC Power Converter for Large Current Applications

Morimoto Keiki,Ahmed Nabil A.,Lee Hyun-Woo,Nakaoka Mutsuo The Korean Institute of Electrical Engineers 2006 Journal of Electrical Engineering & Technology Vol.1 No.2

This paper presents a new circuit topology of DC busline switch and snubbing capacitor-assisted full-bridge soft-switching PWM inverter type DC-DC power converter with a high frequency link for low voltage large current applications as DC feeding systems, telecommunication power plants, automotive DC bus converters, plasma generator, electro plating plants, fuel cell interfaced power conditioner and arc welding power supplies. The proposed power converter circuit is based upon a voltage source-fed H type full-bridge high frequency PWM inverter with a high frequency transformer link. The conventional type high frequency inverter circuit is modified by adding a single power semiconductor switching device in series with DC rail and snubbing lossless capacitor in parallel with the inverter bridge legs. All the active power switches in the full-bridge inverter arms and DC busline can achieve ZVS/ZVT turn-off and ZCS turn-on commutation operation. Therefore, the total switching losses at turn-off and turn-on switching transitions of these power semiconductor devices can be reduced even in the high switching frequency bands ranging from 20 kHz to 100 kHz. The switching frequency of this DC-DC power converter using IGBT power modules is selected to be 60 kHz. It is proved experimentally by the power loss analysis that the more the switching frequency increases, the more the proposed DC-DC converter can achieve high performance, lighter in weight, lower power losses and miniaturization in size as compared to the conventional hard switching one. The principle of operation, operation modes, practical and inherent effectiveness of this novel DC-DC power converter topology is proved for a low voltage and large current DC-DC power supplies of arc welder applications in industry.

Dual Utility AC Line Voltage Operated Voltage Source and Soft Switching PWM DC-DC Converter with High Frequency Transformer Link for Arc Welding Equipment

Morimoto Keiki,Ahmed NabilA.,Lee Hyun-Woo,Nakaoka Mutsuo The Korean Institute of Electrical Engineers 2005 KIEE International Transactions on Electrical Mach Vol.b5 No.4

This paper presents two new circuit topologies of the dc busline side active resonant snubber assisted voltage source high frequency link soft switching PWM full-bridge dc-dc power converters acceptable for either utility ac 200V-rms or ac 400V-rms input grid. These high frequency switching dc-dc converters proposed in this paper are composed of a typical voltage source-fed full-bridge PWM inverter, high frequency transformer with center tap, high frequency diode rectifier with inductor input filter and dc busline side series switches with the aid of a dc busline parallel capacitive lossless snubber. All the active switches in the full-bridge arms as well as dc busline snubber can achieve ZCS turn-on and ZVS turn-off transition commutation with the aid of a transformer leakage inductive component and consequently the total switching power losses can be effectively reduced. So that, a high switching frequency operation of IGBTs in the voltage source full bridge inverter can be actually designed more than about 20 kHz. It is confirmed that the more the switching frequency of full-bridge soft switching inverter increases, the more soft switching PWM dc-dc converter with a high frequency transformer link has remarkable advantages for its power conversion efficiency and power density implementations as compared with the conventional hard switching PWM inverter type dc-dc power converter. The effectiveness of these new dc-dc power converter topologies can be proved to be more suitable for low voltage and large current dc-dc power supply as arc welding equipment from a practical point of view.

DC Rail Side Series Switch and Parallel Capacitor Snubber-Assisted Edge Resonant Soft-Switching PWM DC-DC Converter with High-Frequency Transformer Link

Morimoto, Keiki,Fathy, Khairy,Ogiwara, Hiroyuki,Lee, Hyun-Woo,Nakaoka, Mutsuo The Korean Institute of Power Electronics 2007 JOURNAL OF POWER ELECTRONICS Vol.7 No.3

This paper presents a novel circuit topology of a DC bus line series switch and parallel snubbing capacitor-assisted soft-switching PWM full-bridge inverter type DC-DC power converter with a high frequency planar transformer link, which is newly developed for high performance arc welding machines in industry. The proposed DC-DC power converter circuit is based upon a voltage source-fed H type full-bridge soft-switching PWM inverter with a high frequency transformer. This DC-DC power converter has a single power semiconductor switching device in series with an input DC low side rail and loss less snubbing capacitor in parallel with the inverter bridge legs. All the active power switches in the full-bridge arms and DC bus line can achieve ZCS turn-on and ZVS turn-off transition commutation. Consequently, the total switching power losses occurred at turn-off switching transition of these power semiconductor devices; IGBTs can be reduced even in higher switching frequency bands ranging from 20 kHz to 100 kHz. The switching frequency of this DC-DC power converter using IGBT power modules can be realized at 60 kHz. It is proved experimentally by power loss analysis that the more the switching frequency increases, the more the proposed DC-DC power converter can achieve a higher control response performance and size miniaturization. The practical and inherent effectiveness of the new DC-DC converter topology proposed here is actually confirmed for low voltage and large current DC-DC power supplies (32V, 300A) for TIG arc welding applications in industry.

High-Gain Resonant Switched-Capacitor Cell-Based DC/DC Converter for Offshore Wind Energy Systems

Parastar, Amir,Jul-Ki Seok Institute of Electrical and Electronics Engineers 2015 IEEE transactions on power electronics Vol. No.

<P>With the increasing integration of renewable energy generation into high-power grids, transmission at the dc level is becoming increasingly more useful than ac transmission. In this regard, emerging applications, such as offshore wind farms, require a high voltage gain dc/dc conversion system to interface with high-power transmission networks. This paper presents a new high-voltage gain resonant switched-capacitor dc/dc converter for high-power offshore wind energy systems. The proposed dc/dc converter is characterized by the resonant switching transitions to achieve minimal switching losses and maximum system efficiency. Therefore, a higher switching frequency is conceivable to attain a higher power density. The double stage output voltage of the proposed converter operates at seven times as high as the input voltage with a small device count. The output capacitors are charged and discharged continuously by a 180° phase shift with respect to each other to eliminate the output voltage ripples with the low capacitance requirements. The proposed series-modular and cascade configurations show the intrinsic advantage of being readily applicable to multistage power switching converters. The developed topology has been implemented on a 5-kW prototype converter to test its feasibility.</P>

Design Considerations of Resonant Network and Transformer Magnetics for High Frequency LLC Resonant Converter

Hwa-Pyeong Park,Younggon Ryu,Ki Jin Han,Jee-Hoon Jung 대한전기학회 2016 Journal of Electrical Engineering & Technology Vol.11 No.2

This paper proposes the design considerations of resonant network and transformer magnetics for 500 kHz high switching frequency LLC resonant converter. The high power density can be effectively achieved by adopting high switching frequency which allows small size passive components in the converter. The design methodology of magnetizing inductance is derived for zero voltage switching (ZVS) condition, and the design methodology of the transformer and output capacitance is derived to achieve high power density at high operating frequency. Moreover, the structure of transformer is analyzed to obtain the proper inductance value for high switching operation. To verify the proposed design methodology, simulation and experimental results will be presented including temperature of passive and active components, and power conversion efficiency to evaluate dominant power loss. In addition, the validity of magnetics design will be evaluated with operating waveforms of the prototype converter.

Experimental Study on High Voltage Gain DC-to-DC Boost Type Converter EmployingSwitched-Inductor

오만석,문은아 조선대학교 공학기술연구원 2018 공학기술논문지 Vol.11 No.2

The high boost dc-dc scheme is one most of the topic that attracted the attention of researchers because they have some merits over the conventional boost converter. Recently, a high gain DC-to-DC boost type converter has been introduced by employing switched-inductor. The high gain DC-to-DC boost type converter topology is suitable for high gain conversion applications where a varying low dc input voltage is converted to a high stabilized dc output voltage. In the paper, the experimental results of the novel high gain DC-to-DC boost type converter employing switched-inductor are illustrated. Furthermore, an extended high gain DC-to-DC boost type converter is also proposed. Circuit analysis, operating theories of the extended high gain DC-to-DC boost type converter are presented. Finally, the experimental results of the high gain DC-to-DC boost type converter are also presented to validate the performance of the high gain DC-to-DC boost type converter for the practical implementation.

Experimental Study on High Voltage Gain DC-to-DC Boost Type Converter EmployingSwitched-Inductor

( Man-suck Oh ),( Eun-a Moon ) 조선대학교 공학기술연구원 2018 공학기술논문지 Vol.11 No.2

The high boost dc-dc scheme is one most of the topic that attracted the attention of researchers because they have some merits over the conventional boost converter. Recently, a high gain DC-to-DC boost type converter has been introduced by employing switched-inductor. The high gain DC-to-DC boost type converter topology is suitable for high gain conversion applications where a varying low dc input voltage is converted to a high stabilized dc output voltage. In the paper, the experimental results of the novel high gain DC-to-DC boost type converter employing switched-inductor are illustrated. Furthermore, an extended high gain DC-to-DC boost type converter is also proposed. Circuit analysis, operating theories of the extended high gain DC-to-DC boost type converter are presented. Finally, the experimental results of the high gain DC-to-DC boost type converter are also presented to validate the performance of the high gain DC-to-DC boost type converter for the practical implementation.

New DC Rail Side Soft-Switching PWM DC-DC Converter with High Frequency Planar Transformer

Khairy Sayed,Keiki Morimoto,Soon-Kurl Kwon,Katsumi Nishida,Mutsuo Nakaoka 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

This paper presents a new circuit topology of active edge resonant snubbers assisted half-bridge soft switching PWM inverter type dc-dc high power converter for DC bus feeding power plants. The proposed dc-dc power converter is composed of typical voltage source-fed halfbridge high frequency PWM inverter with a high frequency planar transformer link in addition to input DC busline side power semiconductor switching devices for PWM control scheme and parallel capacitive lossless snubbers. The operating principle of the new DC-DC converter treated here is described by using switching mode equivalent circuits, together with its unique features. All the active power switches in the half-bridge arms and input DC buslines can achieve ZCS turn-on and ZVS turn-off commutation transitions. The total turn-off switching losses of the power switches can be significantly reduced. As a result, a high switching frequency IGBTs can be actually selected in the frequency range of 60 ㎑ under principle of soft switching. The performance evaluations of the experimental setup are illustrated practically. The effectiveness of this new converter topology is proved for low voltage and large current dc-dc power supplies as DC bus feeding from a practical point of view.