Multilevel modular resonant switched-capacitor converter can achieve either zero-current switching (ZCS) or zero-voltage switching (ZVS) by utilizing different converter control strategies. This paper presents a comprehensive way to compare the root mean square (RMS) value of current flowing through switching devices in both ZCS operation and ZVS operation. The study shows that with appropriate converter parameter design, the ZVS operation allows the RMS value of switch current at most 10% lower than that in ZCS operation. Therefore, the converter operating at ZVS mode has the potential to achieve higher efficiency comparing to the converter that operates at ZCS mode due to less semiconductor conduction loss. Furthermore, the ZVS operation can reduce the power loss due to MOSFET output capacitance. A 6x converter with 54V input voltage, 9V output voltage and 600W power rating is used as an example to show the detailed design procedure. Simulation results are provided to verify the theoretical analysis. Also, a 600W lab prototype that has 6 to 1 voltage conversion ratio has been built to verify the theoretical analysis.
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A 100kW Switched-Tank Converter for Electric Vehicle Application
This paper presents a 100kW one-cell switched-tank converter (STC) for electric vehicle (EV) application. A new evaluation method that evaluates different converter topologies has been proposed in this paper to show the advantages of the STC over the boost converter and 3-level flying capacitor multilevel (FCML) converter. Both non-interleaved (1-phase) and interleaved (2-phase and 3-phase) operation of the STC have been analyzed. The analytical study shows that it is difficult to achieve the optimum design of the passive components such as input and output capacitors in 1-phase converter because of the high RMS current flowing through them. This means the passive components need to be over-designed in order to meet the current stress requirement. For instance, the designed capacitance of input capacitor is several times of the required value, which leads to bulky capacitor size. Therefore, this paper evaluates the potentials of using 2-phase and 3-phase interleaved operation to address this issue. Two operation modes, zero-voltage switching (ZVS) mode and zero-current switching (ZCS) mode, are evaluated to show the ZCS operation mode is more suitable for the presented converter with interleaved operation. By using the interleaving concept, the predicted 100kW 3-phase interleaved converter can achieve 60% size reduction based on the 1-phase converter design. And the predicted power density of the 3-phase interleaved STC can achieve 115kW/L power density. Simulation results are provided to validate the theoretical analysis. Both 1-phase and 3-phase 100kW prototypes under developing are shown in this paper.
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- Award ID(s):
- 1810428
- NSF-PAR ID:
- 10109870
- Date Published:
- Journal Name:
- 2019 IEEE Applied Power Electronics Conference and Exposition (APEC)
- Page Range / eLocation ID:
- 1690 to 1697
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/APEC.2019.8721841
