Bidirectional Resonant Converter for DC Microgrid Applications

A bidirectional resonant converter is presented and verified in this paper for an electric vehicle battery charger/discharger system. The presented circuit can achieve forward and backward power operation, low switching losses on active devices, and wide output voltage operation. The circuit structure of the presented converter includes two resonant circuits on the primary and secondary sides of an isolated transformer. The frequency modulation approach is adopted to control the studied circuit. Owing to the resonant circuit characteristic, active devices for both forward (battery charge) and backward (battery discharge) power operation can be turned on at zero voltage switching. In order to implement a universal battery charger for different kinds of electric vehicle applications, the DC converter is demanded to have a wide output voltage range capability. The topology morphing between a full bridge resonant circuit and half bridge resonant circuit is selected to obtain high- and low-output voltage range operations so that the 200–500 V output voltage range is realized in the presented resonant converter. Compared to the conventional bidirectional converters, the proposed can be operated under a wide voltage range operation. In the end, a 1 kW laboratory prototype circuit is built, and experiments are provided to demonstrate the validity and performance of the presented bidirectional resonant converter.

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A Novel Dual Integrated LLC Resonant Converter Using Various Switching Patterns for a Wide Output Voltage Range Battery Charger

Electronics ◽

10.3390/electronics8070759 ◽

2019 ◽

Vol 8 (7) ◽

pp. 759

Author(s):

Bong-Yeon Choi ◽

Soon-Ryung Lee ◽

Jin-Wook Kang ◽

Won-Sang Jeong ◽

Chung-Yuen Won

Keyword(s):

Output Voltage ◽

Voltage Gain ◽

Resonant Converter ◽

Operating Characteristics ◽

Battery Charger ◽

Voltage Range ◽

Switching Pattern ◽

Operating Frequency Range ◽

Switching Patterns ◽

Llc Resonant Converter

This paper proposes a novel dual integrated LLC resonant converter (DI-LRC) with a wide output voltage range using various switching patterns. The primary side of the proposed DI-LLC converter consists of two resonant tanks and six switches, while the secondary side consists of a six-pulse diode rectifier. Depending on the switching pattern of the primary switch, the DI-LRC converter is performed by single full-bridge operation with a voltage gain of 1, series-connected full-bridge operation with a voltage gain of 0.5, series-connected half bridge operation with a voltage gain of 0.25, and parallel-connected full-bridge operation with a voltage gain of 2. Accordingly, the proposed DI-LRC converter has four voltage gain curves with different variations and achieves a wider output voltage range than the conventional single voltage gain curve in a given operating frequency range. In this paper, the equivalent circuits derived for each switching pattern are proposed to analyze the operating characteristics of the proposed converter according to each switching pattern, and each Q factor and voltage gain are calculated based on the analyzed equivalent circuit. The performance of the proposed converter and switching pattern is verified using the simulation and experimental results of the prototype battery charger, which is designed to be 4-kW class.

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High Efficiency Isolated On-Board EV Battery Charger Using LLC Resonant Converter

Journal of Engineering Research ◽

10.36909/jer.10637 ◽

2021 ◽

Author(s):

Sevilay Cetin ◽

Keyword(s):

Output Voltage ◽

High Efficiency ◽

Load Condition ◽

Voltage Regulation ◽

Resonant Converter ◽

Battery Charger ◽

Voltage Range ◽

Wide Range ◽

Electrical Vehicle ◽

Llc Resonant Converter

In this study, high efficiency design of an on-board Electrical Vehicle (EV) battery charger is presented. The presented charger has two stages where the first stage is conventional front-end boost converter and the second stage is LLC resonant converter. The basic principles of both stage are discussed and the detailed design procedures are presented in terms of wide range output voltage regulation, wide range load condition, high efficiency and high power density. The presented design approach is tested with a prototype implemented with 2.5 kW output power at 250 V-450 V output voltage range. The peak efficiency of system is obtained as 95.53% at full load condition.

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Hybrid DC-DC Converter with Low Switching Loss, Low Primary Current and Wide Voltage Operation

Energies ◽

10.3390/en14092536 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2536

Author(s):

Bor-Ren Lin ◽

Yi-Kuan Lin

Keyword(s):

Pulse Width ◽

Pulse Width Modulation ◽

Input Voltage ◽

Resonant Circuit ◽

Switching Loss ◽

Voltage Range ◽

Current Loss ◽

Zero Voltage Switching ◽

Energy Applications ◽

Multi Stage

A full-bridge converter with an additional resonant circuit and variable secondary turns is presented and achieved to have soft-switching operation on active devices, wide voltage input operation and low freewheeling current loss. The resonant tank is linked to the lagging-leg of the full bridge pulse-width modulation converter to realize zero-voltage switching (ZVS) characteristic on the power switches. Therefore, the wide ZVS operation can be accomplished in the presented circuit over the whole input voltage range and output load. To overcome the wide voltage variation on renewable energy applications such as DC wind power and solar power conversion, two winding sets are used on the output-side of the proposed converter to obtain the different voltage gains. Therefore, the wide voltage input from 90 to 450 V (Vin,max = 5Vin,min) is implemented in the presented circuit. To further improve the freewheeling current loss issue in the conventional phase-shift pulse-width modulation converter, an auxiliary DC voltage generated from the resonant circuit is adopted to reduce this freewheeling current loss. Compared to the multi-stage DC converters with wide input voltage range operation, the proposed circuit has a low freewheeling current loss, low switching loss and a simple control algorithm. The studied circuit is tested and the experimental results are demonstrated to testify the performance of the resented circuit.

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Analysis and Implementation of a Frequency Control DC–DC Converter for Light Electric Vehicle Applications

Electronics ◽

10.3390/electronics10141623 ◽

2021 ◽

Vol 10 (14) ◽

pp. 1623

Author(s):

Bor-Ren Lin

Keyword(s):

Electric Vehicles ◽

Output Voltage ◽

Frequency Control ◽

Input Voltage ◽

Pulse Frequency ◽

Switching Frequency ◽

Battery Charger ◽

Dc Microgrid ◽

Load Voltage ◽

Transportation Vehicle

In order to realize emission-free solutions and clean transportation alternatives, this paper presents a new DC converter with pulse frequency control for a battery charger in electric vehicles (EVs) or light electric vehicles (LEVs). The circuit configuration includes a resonant tank on the high-voltage side and two variable winding sets on the output side to achieve wide output voltage operation for a universal LEV battery charger. The input terminal of the presented converter is a from DC microgrid with voltage levels of 380, 760, or 1500 V for house, industry plant, or DC transportation vehicle demands, respectively. To reduce voltage stresses on active devices, a cascade circuit structure with less voltage rating on power semiconductors is used on the primary side. Two resonant capacitors were selected on the resonant tank, not only to achieve the two input voltage balance problem but also to realize the resonant operation to control load voltage. By using the variable switching frequency approach to regulate load voltage, active switches are turned on with soft switching operation to improve converter efficiency. In order to achieve wide output voltage capability for universal battery charger demands such as scooters, electric motorbikes, Li-ion e-trikes, golf carts, luxury golf cars, and quad applications, two variable winding sets were selected to have a wide voltage output (50~160 V). Finally, experiments with a 1 kW rated prototype were demonstrated to validate the performance and benefits of presented converter.

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New parallel loaded resonant converter with wide input and output voltage range

2015 9th International Conference on Power Electronics and ECCE Asia (ICPE-ECCE Asia) ◽

10.1109/icpe.2015.7167834 ◽

2015 ◽

Author(s):

Minjae Kim ◽

Shinyoung Noh ◽

Sewan Choi

Keyword(s):

Output Voltage ◽

Resonant Converter ◽

Voltage Range ◽

Input And Output

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Implementation of a Wide Input Voltage Resonant Converter with Voltage Doubler Rectifier Topology

Electronics ◽

10.3390/electronics9111931 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1931

Author(s):

Bor-Ren Lin ◽

Yen-Chun Liu

Keyword(s):

Input Voltage ◽

Resonant Circuit ◽

Circuit Performance ◽

Voltage Range ◽

Zero Voltage Switching ◽

Renewable Power ◽

Battery Chargers ◽

Variable Voltage ◽

Voltage Doubler ◽

Zero Voltage

A new circuit structure of LLC converter is studied and implemented to achieve wide zero-voltage switching range and wide voltage operation such as consumer power units without power factor correction and long hold up time demand, battery chargers, photovoltaic converters and renewable power electronic converters. The dc converter with the different secondary winding turns is adopted and investigated to achieve the wide input voltage operation (50–400 V). To meet wide voltage operation, the full bridge and half bridge dc/dc converters with different secondary turns can be selected in the presented circuit to have three different voltage gains. According to input voltage range, the variable frequency scheme is employed to have the variable voltage gain to overcome the wide input voltage operation. Therefore, the wide soft switching load variation and wide voltage operation range are achieved in the presented resonant circuit. The prototype circuit is built and tested and the experiments are demonstrated to investigate the circuit performance.

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Bidirectional Interface Resonant Converter for Wide Voltage Range Storage Applications

Sustainability ◽

10.3390/su14010377 ◽

2021 ◽

Vol 14 (1) ◽

pp. 377

Author(s):

Mouncif Arazi ◽

Alireza Payman ◽

Mamadou Baïlo Camara ◽

Brayima Dakyo

Keyword(s):

Electromagnetic Compatibility ◽

Narrow Range ◽

Harmonic Approximation ◽

Design Procedure ◽

Resonant Circuit ◽

Switching Frequency ◽

Resonant Converter ◽

Voltage Range ◽

Wide Range ◽

Storage Units

In this paper, a bidirectional zero voltage switching (ZVS) resonant converter with narrow control frequency deviation is proposed. Wide input–output voltage range applications, such as flywheel or supercapacitors storage units are targeted. Due to symmetrical topology of resonant circuit interfaces, the proposed converter has similar behavior in bidirectional operating mode. We call it Dual Active Bridge Converter (DABC). The proposal topology of the converter is subjected to multi resonant circuits which make it necessary to study with multiscale approaches. Thus, first harmonic approximation and use of selective per unit parameters are established in (2) Methods. Then, the forward direction and backward direction of power flux exchange are detailed according to switching sequences. Switching frequency control must be completed within a narrow range. So, the frequency range deterministic parameters are emphasized in the design procedure in (3) Methods. A narrow range of switching frequency and a wide range voltage control must be ensured to suit for energy storage units, power electronic devices capabilities and electromagnetic compatibility. A 3 kW test bench is used to validate operation principles and to proof success of the developed design procedure. The interest of proposed converter is compared to other solutions from the literature in (4) Results.

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