Study of an Isolated DC-DC Converter for Fuel Cell Applications

2016 ◽  
Vol 839 ◽  
pp. 65-69
Author(s):  
Sakda Somkun ◽  
Shanmugham Prabhuraj ◽  
Chatchai Sirisamphanwong
Keyword(s):  
Fuel Cell ◽  
Output Voltage ◽  
High Efficiency ◽  
Load Range ◽  
Zero Voltage Switching ◽  
Analysis And Design ◽  
Switching Regimes ◽  
Light Load ◽  
Zero Voltage ◽  
Voltage Switching

This paper presents the analysis and design of a dual active bridge DC-DC converter for fuel cell applications. The zero voltage switching operating condition of such converter is analyzed to select an appropriate turn ratio of the high frequency transformer for a high efficiency operation. The ratio between the output voltage to the fuel cell voltage should be close to the transformer turn ratio to guarantee the zero voltage switching regimes at a light load. The prototype converter was designed to be suitable for the input voltage of 40 to 65 V and output voltage of 360 to 400 V with the transformer turn ratio of 7.33. The converter was tested with a 48 V DC power supply and with a polymer electrolyte membrane fuel cell stack. The maximum power of 700 W was delivered and the efficiency was better than 94% for the whole load range.

Phase-shifted Series Resonant Converter with Zero Voltage Switching Turn-on and Variable Frequency Control

2017 ◽  
Vol 8 (3) ◽  
pp. 1184 ◽  
Author(s):  
Mohamed Salem ◽  
Awang Jusoh ◽  
Nik Rumzi Nik Idris ◽  
Tole Sutikno ◽  
Yonis.M.Yonis Buswig
Keyword(s):  
Output Voltage ◽  
Frequency Control ◽  
Switching Frequency ◽  
Resonant Converter ◽  
Zero Voltage Switching ◽  
Light Load ◽  
Wide Range ◽  
Series Resonant ◽  
Zero Voltage ◽  
Voltage Switching

This paper presents a phase shifted series resonant converter with step up high frequency transformer to achieve the functions of high output voltage, high power density and wide range of Zero Voltage Switching (ZVS). In this approach, the output voltage is controlled by varying the switching frequency. The controller has been designed to achieve a good stability under different load conditions. The converter will react to the load variation by varying its switching frequency to satisfy the output voltage requirements. Therefore in order to maintain constant output voltage, for light load (50% of the load), the switching frequency will be decreased to meet the desired output, while for the full load (100%) conditions, the switching frequency will be increased. Since the controlled switching frequency is limited by the range between the higher and lower resonant frequencies , the switches can be turned on under ZVS. In this study, a laboratory experiment has been conducted to verify the effectiveness of the system performance.

ISOLATED HIGH STEP-UP ZERO-VOLTAGE-SWITCHING DC-DC CONVERTER WITH A CONTINUOUS INPUT CURRENT

2011 ◽  
Vol 20 (08) ◽  
pp. 1619-1635 ◽  
Author(s):  
HYUN-LARK DO
Keyword(s):  
High Efficiency ◽  
Input Current ◽  
Leakage Inductance ◽  
Zero Voltage Switching ◽  
Analysis And Design ◽  
High Voltage Gain ◽  
Power Switches ◽  
Continuous Input ◽  
Zero Voltage ◽  
Voltage Switching

An isolated high step-up DC-DC converter with a continuous input current is proposed. The proposed converter consists of two converter cells — a boost converter cell at the input stage for a low input current ripple and a DC-DC converter cell for high voltage gain. Zero-voltage-switching of power switches are achieved and the leakage inductance of the transformer alleviates the reverse-recovery problems of the output diodes. Therefore, the proposed converter achieves high efficiency. Detailed analysis and design of the proposed converter are carried out. A prototype of the proposed converter is developed, and its experimental results are presented for validation.

scholarly journals Event-Focused Digital Control to Keep High Efficiency in a Wide Power Range in a SiC-Based Synchronous DC/DC Boost Converter

Electronics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 2154
Author(s):  
María R. Rogina ◽  
Alberto Rodríguez ◽  
Aitor Vázquez ◽  
Diego G. Lamar ◽  
Marta M. Hernando
Keyword(s):  
Control Strategy ◽  
Digital Control ◽  
High Efficiency ◽  
Wave Mode ◽  
Power Losses ◽  
Control Approach ◽  
Zero Voltage Switching ◽  
Zero Voltage ◽  
Conduction Mode ◽  
Voltage Switching

This paper is focused on the design of a control approach, based on the detection of events and changing between two different conduction modes, to reach high efficiency over the entire power range, especially at medium and low power levels. Although the proposed control strategy can be generalized for different topologies and specifications, in this paper, the strategy is validated in a SiC-based synchronous boost DC/DC converter rated for 400 V to 800 V and 10 kW. Evaluation of the power losses and current waveforms of the converter for different conduction modes and loads predicts suitable performance of quasi-square wave mode with zero voltage switching (QSW-ZVS) conduction mode for low and medium power and of continuous conduction Mode with hard switching (CCM-HS) for high power. Consequently, this paper proposes a control strategy, taking advantage of digital control, that allows automatic adjustment of the conduction mode to optimize the performance for different power ranges.

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