On-board OBC control circuit capable of bidirectionally charging and discharging and control method thereof

An on-board OBC control circuit capable of bidirectionally charging and discharging, comprising a switch module that connects an out-vehicle electric circuit and an in-vehicle electric circuit, and a bidirectional on-board OBC that operates in a charge mode, in a contravariant mode and in an AC/AC mode;

• wherein in the charge mode, the out-vehicle electric circuit charges the bidirectional on-board OBC through the switch module;
• in the contravariant mode, the bidirectional on-board OBC discharges the out-vehicle electric circuit and/or the in-vehicle electric circuit through the switch module;
• in the AC/AC mode, the out-vehicle electric circuit connects the in-vehicle electric circuit through the switch module;
• wherein the switch module comprises a current-limiting resistor R, a fourth switch K4 and a fifth switch K5, the fourth switch K4 is connected between a power line L1 of the out-vehicle electric circuit and a first end O1 of the bidirectional on-board OBC;
• the fifth switch K5 comprises a mobile break-contact head, a mobile make-contact head and a static contact head, the mobile break-contact head is connected in series with the current-limiting resistor R, then connected to the power line L1 of the out-vehicle electric circuit, the mobile make-contact head is connected to a power line L2 of the in-vehicle electric circuit, the static contact head is connected to the first end O1 of the bidirectional on-board OBC;
• a zero line N1 of the out-vehicle electric circuit and a zero line N2 of the in-vehicle electric circuit are connected with each other in parallel, then connected to a second end O2 of the bidirectional on-board OBC.