A novel LLC multi-resonant DC-DC converter with an anti-resonant circuit

Electrical Engineering Japan

2017

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SUMMARY A five‐element multiplex resonant (LLCLC) full‐bridge DC‐DC converter controlled by pulse frequency modulation (PFM) is proposed in this paper. The high frequency (HF)‐link resonant DC‐DC converter proposed herein can perform wide‐range output power and voltage regulation with a narrow frequency range due to an antiresonant tank that works effectively as a wide‐range variable inductor. The advantageous characteristics of the antiresonant tank provide overcurrent protection in the case of the short‐circuited load condition as well as in the startup interval. Thus, the technical challenges of a conventional LLC DC‐DC converter can be overcome, and the reliability of the relevant switch‐mode power supplies can be improved. The operating principle of the LLCLC DC‐DC converter is described, after which its performance is evaluated in an experimental setup based on the 2.5 kW prototype. Finally, the feasibility of the proposed DC‐DC converter is discussed from a practical point of view.

“…As was the case with the LLC DC‐DC converter described above, based on the FHA method the input/output voltage conversion ratio M in the LLCLC DC‐DC converter is

\begin{matrix} true \\ right M & = & left \\ left \frac{1}{a \sqrt{{(1 + \frac{ξ}{ω_{s} L_{m}})}^{2} + {[Q_{r s} (F_{r s} - \frac{1}{F_{r s}}) - Q_{r p} {(F_{r p} - \frac{1}{F_{r p}})}^{- 1}]}^{2}}} \\ right \end{matrix}

ξ = Z_{r s} (F_{r s} - \frac{1}{F_{r s}}) - Z_{r p} {((), F_{r p} - \frac{1}{F_{r p}})}^{- 1}

…”

Section: Llclc Multiplex Resonant Dc‐dc Convertermentioning

confidence: 96%

Z_{s} = ω_{s} L_{s} - \frac{1}{ω_{s} C_{s}}

Z_{p} = {Y_{p}}^{- 1} = \frac{ω_{s} L_{p}}{(1 - {ω_{s}}^{2} L_{p} C_{p})}

…”

Section: Llclc Multiplex Resonant Dc‐dc Convertermentioning

confidence: 99%

Section: Llc Resonant Dc-dc Convertermentioning

confidence: 99%

See 1 more Smart Citation

A Five‐Element Multiplex Resonant Full‐Bridge DC‐DC Converter with a Variable Inductive Reactance

Electrical Engineering Japan

2017

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“…As effective solutions to those disadvantages, the fiveelement multi-resonant (LLC − LC) dc-dc converter as illustrated in Fig.3 has been proposed by the authors for the wide-range output power and voltage regulations in one-stage power converter [10]- [12]. By applying the an anti-resonant circuit to the primary side of the HF transformer in an LLC dc-dc converter, the frequency variation for achieving the buck operation with PFM is much smaller as compared with the LLC dc-dc converter [11].…”

Section: Introductionmentioning

confidence: 99%

A dual pulse modulated five-element multi-resonant DC-DC converter and its performance evaluations

2013 IEEE Energy Conversion Congress and Exposition

2013

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A five-element multi-resonant (LLC − LC) dc-dc converter can attain the wide range output power and voltage regulations by a practical-range pulse frequency modulation (PFM). It is a drawback, however, the power conversion efficiency deteriorates under the light load condition due to the conduction power loss in the LC anti-resonant circuit. As a solution to this technical problem, the pulse density modulation (PDM) is applied to the LLC −LC dc-dc converter as the submode power regulation scheme. In this paper, the essential performances of the new prototype of the PFM/PDM dual mode controlled LLC − LC dcdc converter are presented with the experimental verification. The comparison between the LLC − LC dc-dc converter and the conventional LLC dc-dc converter is described in terms of efficiency as well as output voltage and power regulations characteristics, and the effectiveness of the LLC − LC dc-dc converter is evaluated from a practical point of view. I. INTRODUCTIONAn LLC dc-dc converter utilizing parasitic parameters in the high-frequency (HF) transformer has excellent characteristics of a low EMI noise, soft-switching operations over the widerange output power variations, and high efficiency [1]-[5].One of the practical applications of the LLC dc-dc converters could be the front-end dc-dc converter in a plasma radio frequency (RF) power generator for semiconductor manufacturing machinery. Fig.1(a) and (b) illustrate the typical electric power conversion process of the plasma power generator. The plasma chamber has a wide range of load power variations, thereby the wide-range output power and voltage regulations are demanded for its power converters, especially in the frontend dc-dc converter.The conventional concept of the power conversion scheme for the wide-range voltage and power regulations consists of the two-stage power conversion [6]. The first stage of this power processing is the buck-boost dc-dc converter which regulates the dc voltage and power by pulse-amplitudemodulation (PAM). This power converter is followed by a HF-link dc-dc converter operating as the electric transformer. Although the power factor correction can be ensured together with PAM, the power conversion efficiency might be degraded in the light load condition due to the number of circuit components, which is also another disadvantage with respect to cost effectiveness.

“…In particular, the frequency variation for achieving the buck operation based on pulse-frequency-modulation (PFM) is much small as compared with an LLC dc-dc converter. Therefore, the PFM-based output power and voltage regulations can be attained in the practical switching frequency variation [1], [2]. Thus, the five-element multi-resonant dc-dc converter treated herein can be applied to the EV/PHEV battery chargers in vehicle to grid (V2G) as shown in Fig.1.…”

Section: Introductionmentioning

confidence: 99%

Experimental evaluations of a five-element multi-resonant DC-DC converter with an improved PFM control range

2013 IEEE 10th International Conference on Power Electronics and Drive Systems (PEDS)

2013

An LLC multi-resonant DC-DC converter with antiresonant tank is presented in this paper. The five-element multiresonant (LLC-LC) dc-dc converter can realize the wide range regulations of output voltage and power by pulse frequency modulation (PFM) under soft switching conditions. The resonant dc-dc converter proposed herein is suitable for renewable and sustainable energy applications such as battery chargers interfaced with a photovoltaic power generation system. In this paper, the design guideline of circuit parameters is originally described. Experiment results on the soft-switching performances and steady-state characteristics including the power loss analysis are demonstrated, thereby the effectiveness is verified from a practical point of view.