In this article, based on the LLC resonant converter fundamental harmonic analysis model, modulation strategies for can be categorized into following three groups: 1) input voltage modulation; 2) tank elements and 3) secondary equivalent impedance modulation. Operational principles control diagrams different are given. Comprehensive comparisons between these in terms of topology complexity, gain range presented with respect to same system specifications. The advantages disadvantages each...

A kind of interleaved non-isolated high step-up DC/DC converter is presented in this study. The consists two basic Boost cells and some diode–capacitor multiplier (DCM) as needed. Because the DCM cells, voltage conversion ratio enlarged extreme large duty can be avoided applications. Moreover, stress all power devices greatly lower than output voltage. As a result, lower-voltage-rated employed, higher efficiency expected. Since are controlled by interleaving method, which means phase...

In order to realize power flow control among photovoltaic (PV) panel port, battery and load port in the distributed generation system, integrated three-port dc-dc converters (TPCs) are widely adopted. The objective of this article is provide a comprehensive, comparative, insightful analysis overview these TPCs. First, based on transmission requirements five topological structures conversion system (TPCS) composed two or three two-port presented. And comparatively analyzed. Second,...

In this paper, a dual half-bridge <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LLC</i> resonant converter with magnetic control is proposed for the battery charger application. The primary switches are shared by two networks, and their outputs connected in series. One of converters designed to operate at series frequency, which also highest efficiency operating point, constant output voltage characteristic achieved point. second adopts...

The LLC resonant converters commonly adopt frequency modulation (FM) or combination of FM with phase-shift to regulate its output voltage. However, in these control schemes, a variable switching range is required, which makes the magnetic components design complicated. Therefore, this article, (or inductor control) adopted make converter operating at constant and duty cycle. fundamental harmonic analysis used because characteristic simplicity. accuracy method reduced considerable errors...

LLC resonant converters have been widely used in many different industrial applications. Analysis and design methodologies great effect on the converter performance. Accordingly, a complete step-by-step optimal methodology based time-domain analysis has proposed for an this article. The is implemented under worst operation condition, following considerations are included to obtain suitable area: mode; voltage stress capacitor; zero switching primary switches; tank root-mean-square current....

This article performs a comprehensive steady-state performance optimization for the isolated triple active bridge (TAB) dc–dc converter adopting five-variable modulation (FVM) technique. First of all, universal analytical model suitable all hardware conditions TAB is established using frequency-domain analysis method. Second, considering influence port voltages and energy stored in parasitic capacitances, simplified accurate zero-voltage switching (ZVS) constraint derived without complicated...

In this paper, a multiple-input high step-up boost converter is presented for grid-connected photovoltaic power generation system. Firstly, the derivation of with dual input and its operation principle steady state performance arc analyzed in detail. Secondly, n-input made up n cells deduced. Its ratio relationship among currents are analyzed. Finally, an experimental prototype rated 100 W built results given.

Insulated-gate bipolar transistor (IGBT) modules and dc-link capacitors are important parts in the majority of power electronic converters which contribute to cost, size, failure rate on a considerable scale. This paper presents an online condition monitoring method for both IGBT based short-circuit current module, is good indicator according theory analysis. The prediction dc-Link capacitor realized by equivalent series resistance, can be calculated step voltage, bond wires fatigue also...

Conventionally, LLC resonant converter adopts frequency control (FC) or combine FC with phase shift (PSC) to regulate the output voltage.However, for both strategies, a variable switching operation range is required, which makes magnetic component and driver circuit design complicated.In this paper, (MC) inductor adopted converter.Thanks MC, constant duty cycle can be implemented primary switches.A comprehensive analysis of magnetically controlled presented, includes principle, voltage gain,...

High step-up boost converters with coupled inductor have attracted much attention in the fuel cell or photovoltaic grid-connected generation system, however, there are few literatures elaborated on construction ideas and derivation methods of them. Accordingly, order to obtain a clear roadmap inner connection these converters, comprehensive review analysis presented this paper. First, basic converter is regarded as topology, its merits demerits analyzed detail. Then, address demerits,...

LLC resonant converter is one of the most popular isolated dc/dc converters owning to its advantages simple control, wide voltage gain regulation capability, and soft switching operation. Nevertheless, high efficiency power density are always goals for converters. To further increase conversion efficiency, synchronous rectification (SR) technology adopted, where uncontrolled diodes on secondary side replaced with SR MOSFETs. Due extreme low on-state resistance value MOSFET, considerable...

In this letter, a magnetically controlled single-stage ac-dc converter is proposed for low-power application which has the following features. First, operation achieved by sharing switches between LLC resonant and totem-pole bridgeless power factor corrector (PFC) converter. Second, correction function inherently designing PFC to operate in discontinuous conduction mode. Third, dc-link voltage almost constant. Fourth, fixed switching frequency duty cycle can be implemented switches,...

The LLC resonant converters have been widely used in many applications due to their features such as wide input voltage range, high efficiency, and power density. Therefore, the analysis methodology for converter is of great importance. Based on existing literature, there are mainly four methodologies: (i) fundamental harmonic analysis; (ii) frequency domain with time partial correction; (iii) complete (iv) or operation mode-based analysis. However, no systematic view study different...

A five-degree-of-freedom (5-DOF) modulation scheme is proposed in this article for dual active bridge converter to improve its efficiency a wide operation range. First, the possible modes of under 5-DOF analyzed. As result, 11 effective are obtained and their steady-state characteristics expressions solved, including inductor root-mean-square (rms) current, peak-to-peak transmission power, etc. It worth mentioning that current expression simple it can be regarded as an indicator rms current....

Asymmetric duty modulation (ADM), as a recently proposed scheme, provides new chance to improve the performance of dual active bridge (DAB) converter. On this basis, an optimal ADM (OADM) scheme is in article minimize inductor peak-to-peak current over whole voltage and power range. First, DAB converter adopting analyzed frequency-domain time-domain, four operating modes are established. Then, minimum for each mode obtained under Karush-Kuhn-Tucker condition, corresponding closed-loop...

In order to further improve the efficiency of dual-active-bridge (DAB) converter, a hybrid five-variable modulation scheme with minimal root mean square (rms) current is proposed in this article, which combines traditional phase-shift and pulsewidth schemes. By adopting optimal scheme, wider zero-voltage switching (ZVS) operation range lower rms level are achieved simultaneously when compared other schemes, significantly improves DAB converter. Moreover, for complexity five variables,...

With the widespread application of lithium-ion battery packs, it calls for efficient balancing methods to improve performance these systems. The relevant research has focused on design equalization circuits and control strategies while neglecting quantitative analysis comparison active structures from systematic level. In this paper, we propose an improved system-theoretic modeling approach that takes into account battery's constraints, including current rate SOC operation range....

Multiport power electronic transformers (PET) are widely used in modern systems to facilitate flexible interconnection between various ac or dc buses, sources, and loads. However, due the wide range of "source-load-storage" operating points, achieving efficient operation isolated dc–dc converter PET can be challenging. This letter focuses on modular multiactive bridge (MMAB) PET, proposes an optimization modulation scheme based reactive minimization (RPM) improve efficiency. The RPM utilizes...

Low-voltage enhancement-mode gallium nitride high electron mobility transistors (eGaN HEMTs) are a kind of promising devices to realize high-efficiency and high-power-density conversion because their fast switching speed, low conduction, losses. Since the reverse conduction loss eGaN HEMTs accounts for large part losses, it is great importance improve traditional analytical model predict loss. In this paper, complete accurate low-voltage presented, which considers effects low-parasitic...

Grid-connected current quality is seriously affected by the low-order background harmonics in gird-inverter dynamic system. The point of common coupling voltage feedforward impedance reshaping method grid-connected inverter generally applied to solve this problem, however about 90° phase lag output brought in, which would deteriorate adaptability weak grid. To article proposes a novel frequency-division virtual shaping method, shapes with different coefficients frequency bands, respectively....

Although LLC converters are attractive in industrial applications due to its advantages of soft switching, high efficiency, and simple control, wide voltage gain range applications, large switching frequency operating is required, which may cause the loss operation existence control instability issue. In this article, a novel converter with two resonant tanks proposed. The proposed has three modes, namely, dual full-bridge mode, half-bridge can cover range, medium low operations,...