CHARGING AND DISCHARGING DEVICE AND CHARGING AND DISCHARGING SYSTEM OF ELECTRIC VEHICLE

A charging and discharging device includes a transformer consisting of a primary winding and multiple secondary windings including at least a first secondary winding and a second secondary winding; multiple ports electrically connected to the primary winding and the multiple secondary windings of the transformer, respectively, wherein the multiple ports at least include a first port electrically connected to the primary winding via a first conversion circuit; a second port electrically connected to the first secondary winding via a second conversion circuit; and a third port electrically connected to the second secondary winding via a third conversion circuit; and a first controllable switch connected between the first conversion circuit and the primary winding.