dc.description.abstract | In recent years, the awareness of environmental protection has risen
and electric vehicles have flourished. Due to the presence of both 12 V
and 48 V systems in automobiles, this paper designs a bidirectional
DC/DC converter with adjustable power. The main function is to dispatch
the energy flow between 12V and 48V system in the automobile. With the
design of this converter, electric energy can be transmitted in both
directions according to load requirements to meet different voltage
systems in the car, and at the same time, it has a fairly high conversion
efficiency.
The hardware architecture of this article is mainly an interleaved
synchronous rectification (Synchronous Rectification) two-way
conversion circuit, using the model LTC3871 chip produced by Linear
Corporation (which was acquired by ADI in 2016), which has a soft start
circuit (Soft Start) , Voltage and current dynamic adjustment,
overvoltage and overcurrent protection, thermal shutdown (Thermal
Shutdown) and multi-phase current-sharing mechanism (Current-Sharing
mechanism) and other functions. The maximum switching frequency of
this chip can be up to 550 kHz when it operates independently, and it can
also use its internal Phase Lock Loop to generate a synchronization signal
of up to 460 kHz to perform up to 12 phases (6 ICs, each IC has 2 phases)
The interlocking operation enables it to work at high frequencies to
reduce the volume of passive components, make full use of the limited
space in the car and meet the demand for high power at the same time; in
addition, it also cooperates with synchronous rectification technology to
further improve the conversion efficiency. | en_US |