Brusa BDC546, Technical Data And Start-Up

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Technical data
and start-up
BDC546
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6.4 Basic function / EMC concept
The BDC546 is a bi-directional DC/DC converter that is applied as connection between different HV voltage ranges
in vehicles. Specifically, the component can be used as connection between HV batteries and battery systems with
other voltage levels. It is also possible to use the BDC546 as coupling between a HV battery and power electronic
devices like frequency inverters, on-board converters, etc. Ideally, the component is used as interface between fuel
cell systems and HV batteries. These are only a few of the potential applications of the BDC546.
The BDC546 works with eight phases with phase-shifted clocking. Each phase corresponds to a boost/buck
converter. For half bridge clocking, the patented switching strategy SoftSwing® is applied. It not only enables highly
efficient operation of the component but also guarantees very low EMC emissions. Additionally, the low switching
losses enable clocking at very high switching frequencies. In combination with the high number of phase-shifted,
clocking half bridges, this makes it possible to achieve excellent ripple reduction.
6.4.1 Topology benefits
The switching processes in the phases of the BDC546 are realized by means of the resonant topology SoftSwing®.
Power semiconductors are disconnected from the mains and de-energised. During deactivation, the choke current
is taken up by the commutation capacities that enable slow “zero current switching”. Thanks to this process, very
low switching losses can be achieved. On the other hand, the EMC interferences caused by transient processes
are considerably reduced due to the slow changes during the switching processes in comparison to hard-switching
topologies.