Power conversion device

A power conversion device, comprising:

• an input positive terminal, an input negative terminal, an output positive terminal, an output negative terminal and a three-switch bridge arm, wherein the input negative terminal is in short connection with the output negative terminal;
• wherein the three-switch bridge arm is bridged between the input positive terminal and the input negative terminal and comprises a first upper switch, a first middle switch and a first lower switch, the first upper switch and the first middle switch are electrically connected to a first upper node, and the first middle switch and the first lower switch are electrically connected to a first lower node;
• wherein the power conversion device further comprises a second lower switch, a winding combination, a first flying capacitor, an input capacitor and an output capacitor, and the winding combination comprises a first end, a second end and a third end;
• the first end of the winding combination is electrically connected to the first lower node, the second end of the winding combination and the second lower switch are electrically connected to a second lower node, the second lower switch is bridged between the second lower node and the input negative terminal, the third end of the winding combination is electrically connected with the output positive terminal, and the first flying capacitor is bridged between the first upper node and the second lower node;
• wherein the input capacitor is bridged between the input positive terminal and the input negative terminal, and the output capacitor is bridged between the output positive terminal and the output negative terminal;
• wherein the winding combination further comprises a first low-voltage winding and a second low-voltage winding, the first low-voltage winding and the second low-voltage winding are connected in series and bridged between the first end and the second end, and a number of turns of the first low-voltage winding is the same as a number of turns of the second low-voltage winding;
• wherein the power conversion device further comprises a first clamping diode, a first absorption capacitor and a clamping bridge arm circuit;
• a positive electrode of the first clamping diode is electrically connected with the first lower node, and a negative electrode of the first clamping diode is electrically connected with a first clamping point;
• one end of the first absorption capacitor is electrically connected with the first clamping point, and the other end of the first absorption capacitor is electrically connected with the input negative terminal;
• one end of the clamping bridge arm circuit is electrically connected with the first clamping point, and the other end of the clamping bridge arm circuit is electrically connected with the input positive terminal;
• and the clamping bridge arm circuit comprises a clamping winding, the clamping winding, the first low-voltage winding and the second low-voltage winding are magnetically coupled.

A power conversion device, comprising:

• an input positive terminal, an input negative terminal, an output positive terminal, an output negative terminal, a three-switch bridge arm, an upper node and a lower node, wherein the input negative terminal and the output negative terminal are short-circuited;
• the upper node comprises a first upper node and a second upper node, and the lower node comprises a first lower node and a second lower node;
• the input negative terminal and the output negative terminal are short-circuited;
• wherein the three-switch bridge arm is bridged between the input positive terminal and the input negative terminal and comprises a first upper switch, a first middle switch and a first lower switch, the first upper switch and the first middle switch are electrically connected to the first upper node, and the first middle switch and the first lower switch are connected to the first lower node;
• wherein the power conversion device further comprises a second lower switch, a winding combination, a first flying capacitor, an input capacitor and an output capacitor, and the winding combination comprises a first end, a second end and a third end;
• the first end of the winding combination is electrically connected to the first lower node, the second end of the winding combination and the second lower switch are electrically connected to the second lower node, the second lower switch is bridged between the second lower node and the input negative terminal, the third end of the winding combination is electrically connected with the output positive terminal, and the first flying capacitor is bridged between the first upper node and the second lower node;
• wherein the input capacitor is bridged between the input positive terminal and the input negative terminal, and the output capacitor is bridged between the output positive terminal and the output negative terminal;
• wherein the power conversion device further comprises a first clamping diode, a first absorption capacitor and a first linear voltage stabilizing circuit, wherein a positive electrode of the first clamping diode is electrically connected with one of the first lower node and the second lower node, a negative electrode of the first clamping diode is electrically connected with one end of the first absorption capacitor, the other end of the first absorption capacitor is electrically connected with the input negative terminal, and the negative electrode of the first clamping diode is electrically connected with one end of the first linear voltage stabilizing circuit.

A power conversion device, comprising:

• an input positive terminal, an input negative terminal, an output positive terminal, an output negative terminal, a three-switch bridge arm, an upper node and a lower node, wherein the upper node comprises a first upper node and a second upper node, and the lower node comprises a first lower node and a second lower node;
• the input negative terminal and the output negative terminal are short-circuited;
• wherein the three-switch bridge arm is bridged between the input positive terminal and the input negative terminal, the three-switch bridge arm comprises a first upper switch, a first middle switch and a first lower switch, the first upper switch and the first middle switch are electrically connected to the first upper node, and the first middle switch and the first lower switch are connected to the first lower node;
• wherein the power conversion device further comprises a second lower switch, a low-voltage winding, an inductor winding, a first flying capacitor, an input capacitor and an output capacitor;
• the low-voltage winding comprises a first low-voltage winding and a second low-voltage winding, a first end of the first low-voltage winding is electrically connected to the first lower node, a first end of the second low-voltage winding is electrically connected with the second lower node, a second end of the first low-voltage winding and a second end of the second low-voltage winding are electrically connected with one end of the inductor winding, and the other end of the inductor winding is electrically connected with the output positive terminal;
• the second lower switch is bridged between the second lower node and the input negative terminal, and the first flying capacitor is bridged between the first upper node and the second lower node;
• wherein the input capacitor is bridged between the input positive terminal and the input negative terminal, and the output capacitor is bridged between the output positive terminal and the output negative terminal;
• wherein the power conversion device further comprises an auxiliary winding, a first sampling resistor and a first sampling capacitor, the auxiliary winding, the first sampling resistor and the first sampling capacitor are electrically connected in series to form a first series sampling branch, and the first series sampling branch is bridged between one of the first lower node and the second lower node and the output positive terminal;
• the auxiliary winding comprises a first auxiliary winding and a second auxiliary winding, the first auxiliary winding is coupled with one of the first low-voltage winding and the second low-voltage winding, the second auxiliary winding is coupled with the inductor winding, and a voltage at two ends of the first sampling capacitor is a first current sampling voltage;
• and the first auxiliary winding and the second auxiliary winding are electrically connected in series, and the auxiliary winding is wound along a winding path of the low-voltage winding and the winding path of the inductor winding.