SLLA498 October 2020
Table 4-1 shows the summary of the DC/DC topologies discussed.
Interleaved Synchronous Boost | Phase-shifted Full Bridge (PSFB) | LLC | CLLC | Dual-active Bridge (DAB) | Active clamped current-fed bridge | |
|---|---|---|---|---|---|---|
Device stress | Low | Low | High | High | Lowest | High |
Transformer rating | Non-isolated | Medium | High | High | Low | Medium |
Power output to transformer rating | Non-isolated | Medium | Low | Medium | High | Medium |
Capacitor RMS currents | Low (Input) Medium (output) | Medium | High | High | Low | High |
Polarity | Bidirectional | Unidirectional | Unidirectional | Bidirectional | Bidirectional | Bidirectional |
Conduction losses | Low | Medium | High | Medium | Lowest | Medium |
Turn ON switching loss | High (Hard Switching) | ZVS | ZVS | ZVS | ZVS | ZVS |
Turn OFF switching loss | High (Hard Switching) | High | Low on primary side; secondary side turn off is ZCS | Low on primary side; secondary side turn off is ZCS | High (device turn off at high current) | High on primary side; low on secondary side |
Total losses | High | High | Low | Low | Medium | High |
Control complexity | Simple | Simple | Moderate | Moderate | Simple to complex | Simple |
Wide panel Voltage, Fixed Bus Voltage | Yes | Yes (with reduced efficiency) | No, needs additional DC/DC stage | Limited range | Yes (with reduced efficiency) | Yes |
Paralleling Modules | Easy | Easy | Intensive | Intensive | Easy | Easy |
Switching Frequency | Fixed/ Medium | Fixed/High | Variable/ High (Si /SiC) | Variable/Very High (SiC/GaN) | Fixed/High | Fixed/Medium |