Bi-directional isolated DC-DC converter for the electrification of transportation

A bi-directional DC-DC converter (20) comprising:

• a first stage (30) comprising:
• a first port (22) connected between a first node (N1) and ground;
• the first port (22) being bi-directionally operable as an output or an input;
• the first port (22) being operatively connected to a primary winding (80) of a first transformer (Tr1);
• a second stage (40) comprising:
• a second port (24) connected between seventh and eighth nodes (N7), (N8);
• the second port (24) being bi-directionally operable as an output or an input;
• the second port (24) being operatively connected to a secondary winding (82) of the first transformer (Tr1);
• the secondary winding of the first transformer having first and second terminals;
• a fifth switch (S5) having first and second terminals
• the fifth switch having a body diode,
• an anode of the body diode of the fifth switch being connected to the second terminal of the fifth switch,
• a cathode of the body diode of the fifth switch being connected to the first terminal of the fifth switch;
• a sixth switch (S6) having first and second terminals
• the sixth switch having a body diode,
• an anode of the body diode of the sixth switch being connected to the second terminal of the sixth switch,
• a cathode of the body diode of the sixth switch being connected to the first terminal of the sixth switch;
• a seventh switch (S7) having first and second terminals
• the seventh switch having a body diode,
• an anode of the body diode of the seventh switch being connected to the second terminal of the seventh switch,
• a cathode of the body diode of the seventh switch being connected to the first terminal of the seventh switch;
• an eighth switch (S8) having first and second terminals
• the eighth switch having a body diode,
• an anode of the body diode of the eighth switch being connected to the first terminal of the eighth switch,
• a cathode of the body diode of the eighth switch being connected to the second terminal of the eighth switch;
• a first resonant inductor (Lr1) having first and second terminals;
• a first resonant capacitor (Cr1) having first and second terminals;
• a second resonant capacitor (Cr2) having first and second terminals;
• a third resonant capacitor (Cr3) having first and second terminals;
• a fourth resonant capacitor (Cr4) having first and second terminals;
• the first terminal of the fifth switch (S5) being connected to the seventh node (N7), the second terminal of the fifth switch (S5) being connected to a sixth node (N6);
• the first terminal of the sixth switch (S6) being connected to the sixth node (N6);
• the second terminal of the sixth switch (S6) being connected to the eighth node;
• the first terminal of the seventh switch (S7) being connected to a tenth node (N10);
• the second terminal of the seventh switch (S7) being connected to an eleventh node (N11);
• the first terminal of the eighth switch (S8) being connected to the eleventh node (N11);
• the second terminal of the eighth switch (S8) being connected to a twelfth node (N12);
• the first terminal of the secondary winding (82) of the first transformer (Tr1) being connected to the sixth node (N6);
• the second terminal of the secondary winding (82) of the first transformer (Tr1) being connected to a ninth node (N9);
• the first terminal of the first resonant inductor (Lr1) being connected to the ninth node (N9);
• the second terminal of the first resonant inductor (Lr1) being connected to the tenth node (N10);
• the first terminal of the first resonant capacitor (Cr1) being connected to the seventh node (N7);
• the second terminal of the first resonant capacitor (Cr1) being connected to the twelfth node (N12);
• the first terminal of the second resonant capacitor (Cr2) being connected to the twelfth node (N12);
• the second terminal of the second resonant capacitor (Cr2) being connected to the eighth node (N8);
• the first terminal of the third resonant capacitor (Cr3) being connected to the seventh node (N7);
• the second terminal of the third resonant capacitor (Cr3) being connected to the tenth node (N10);
• the first terminal of the fourth resonant capacitor (Cr4) being connected to the tenth node (N10);
• the second terminal of the fourth resonant capacitor (Cr4) being connected to the eighth node (N8).