This paper presents a novel bidirectional current-fed push-pull DC-DC converter geography with galvanic isolation. The control algorithm proposed enables full-soft-switching of all transistors in a wide range of input voltage and power with no necessity or snubbers or resonant switching.
The converter features an active voltage doubler rectifier controlled by the switching sequence synchronous to that of the input-side switches. As a result, full-soft-switching operation at a fixed switching density is produce. Operation principle for the energy transfer in both directions is express, followed by verification with a 300 W experimental prototype.
The converter has rather higher voltage step-up work than traditional current-fed converters Experimental results get are in good agreement with the logical steady-state analysis.
- Current-fed dc-dc converter
- Bidirectional converter
- Push-pull converter
- Switching control method
Fig. 1. Full-soft-switching CF push-pull converter proposed.
Fig. 2. Simulation current and voltage waveforms of the switch S1.1.
Fig. 3. Simulation current and voltage waveforms of the switch S1.2.
Fig. 4. Simulation current and voltage waveforms of the switch S4.
A novel bidirectional current-fed push-pull converter with galvanic isolation was introduced. It features full-soft switching operation of all semiconductor components, while its DC voltage gain is higher than in traditional current-fed converters due to the application of the flowing energy for the input voltage step-up. As a result, it does not suffer from short intervals of energy transfer from the input side to the output side since at least half of the switching period is loyal for this.
Moreover, it does not require any fastener circuits, since the novel control algorithm features natural clamping of the switches at the current-fed side. Despite a almost high number of semiconductor components, it shows the peak ability of 96.3%, which does not depend on the energy transfer direction for the ability operating point.
Soft-switching operation with continuous current at the current fed side makes the converter planned suitable for residential battery energy storage systems. Further research will be directed towards experimental verification of the converter work with a lithium iron phosphate battery.
- Blaabjerg, and D.M. Ionel, “Renewable Energy Devices and Systems – State-of-the-Art Technology, Research and Development, Challenges and Future Trends,” Electric Power Components and Systems, vol.43, no.12, pp.1319-1328, 2015.
- C, Heymans, S, B. Walker, S. B. Young, M. Fowler, “Economic analysis of second use electric vehicle batteries for residential energy storage and load-levelling,” Energy Policy, vol. 71, pp. 22-30, Aug. 2014.
- Weniger, T. Tjaden, V. Quaschning, “Sizing of Residential PV Battery Systems,” Energy Procedia, vol. 46, pp. 78-87,2014.
- J. Chiang, K. T. Chang and C. Y. Yen, “Residential photovoltaic energy storage system,” IEEE Trans. Ind. Electron., vol. 45, no. 3, pp. 385-394, Jun 1998.
- X. Chen, H. B. Gooi and M. Q. Wang, “Sizing of Energy Storage for Microgrids,” IEEE Trans. Smart Grid, vol. 3, no. 1, pp. 142-151, 2012.