What is bidirectional DC fast charging?

Bidirectional DC fast charging is not only a way to increase the speed of home and work charging without putting a big, heavy, expensive rectifier inside of the vehicle but it is also a way to feed back into the grid or home when the vehicle battery charge isn’t needed.

What is a bidirectional power supply?

A bidirectional power supply demands a different design approach compared to an equivalent unidirectional supply. A unidirectional AC/DC power supply designed for high efficiency uses wide bandgap (WBG) SiC or GaN power devices with a totem-pole power factor correction (PFC) front end driving a DC/DC topology such as an LLC resonant converter.

Do EV charging stations need bidirectional power supplies?

Scenarios that call for bidirectional power supplies in EVs and EV charging stations include: EV supplying power back to the grid or to a microgrid in the home. EV charging station supplying power to an EV either from the grid or from stored energy depending on relative electricity prices.

Are EV charging stations unidirectional?

Current EV charging stations and EV onboard chargers (OBC) are unidirectional systems, but these new use cases are driving a transition to a bidirectional infrastructure. Scenarios that call for bidirectional power supplies in EVs and EV charging stations include: EV supplying power back to the grid or to a microgrid in the home.

What is a unidirectional AC/DC power supply?

A unidirectional AC/DC power supply designed for high efficiency uses wide bandgap (WBG) SiC or GaN power devices with a totem-pole power factor correction (PFC) front end driving a DC/DC topology such as an LLC resonant converter. Although the totem-pole PFC topology is bidirectional, the resonant LLC is not.

Is a resonant LLC a bidirectional PFC?

Although the totem-pole PFC topology is bidirectional, the resonant LLC is not. For bidirectional applications, a CLLC resonant converter is preferred for the DC/DC stage, as it combines high efficiency with a wide output voltage range in both charging and discharging modes.