A converter, comprising: a first bridge arm comprising a first switch unit and a second switch unit electrically coupled in series at an output terminal; a second bridge arm comprising a first voltage source and a second voltage source electrically coupled in series at a neutral point terminal, wherein the first voltage source and the second voltage source are arranged between a positive input terminal and a negative input terminal; a third switch unit and a fourth switch unit electrically coupled in series at a common connection terminal and arranged between the neutral point terminal and the output terminal; and a voltage clamp circuit electrically coupled to the output terminal, the common connection terminal, the neutral point terminal, and one of the positive input terminal and negative input terminal, wherein the voltage clamp circuit is shared by the third switch unit and the fourth switch unit to clamp voltages across the third switch unit and the fourth switch unit wherein the voltage clamp circuit comprises: a sharing circuit, electrically coupled to the output terminal, the common connection terminal and the neutral point terminal, wherein the sharing circuit is configured to clamp voltages across the third switch unit and the fourth switch unit and configured to store a clamping voltage; wherein the sharing circuit comprises a capacitor (Ccom) electrically coupled between the node and the common connection terminal, a first diode electrically coupled between a node and the neutral point terminal, and a second diode electrically coupled between the node and the output terminal; characterized in that the voltage clamp circuit further comprises an active circuit electrically coupled to the sharing circuit and configured to output an operation voltage to one of the positive input terminal, negative input terminal, the output terminal, and a driving circuit, according to the clamping voltage, wherein the driving circuit is configured to drive the third switch unit or the fourth switch unit; wherein the active circuit comprises a DC-to-DC converter including input terminals electrically coupled to two terminals of the capacitor, and output terminals electrically coupled to the driving circuit. a first bridge arm comprising a first switch unit and a second switch unit electrically coupled in series at an output terminal; a second bridge arm comprising a first voltage source and a second voltage source electrically coupled in series at a neutral point terminal, wherein the first voltage source and the second voltage source are arranged between a positive input terminal and a negative input terminal; a third switch unit and a fourth switch unit electrically coupled in series at a common connection terminal and arranged between the neutral point terminal and the output terminal; and a voltage clamp circuit electrically coupled to the output terminal, the common connection terminal, the neutral point terminal, and one of the positive input terminal and negative input terminal, wherein the voltage clamp circuit is shared by the third switch unit and the fourth switch unit to clamp voltages across the third switch unit and the fourth switch unit wherein the voltage clamp circuit comprises: a sharing circuit, electrically coupled to the output terminal, the common connection terminal and the neutral point terminal, wherein the sharing circuit is configured to clamp voltages across the third switch unit and the fourth switch unit and configured to store a clamping voltage; wherein the sharing circuit comprises a capacitor (Ccom) electrically coupled between the node and the common connection terminal, a first diode electrically coupled between a node and the neutral point terminal, and a second diode electrically coupled between the node and the output terminal; characterized in that the voltage clamp circuit further comprises an active circuit electrically coupled to the sharing circuit and configured to output an operation voltage to one of the positive input terminal, negative input terminal, the output terminal, and a driving circuit, according to the clamping voltage, wherein the driving circuit is configured to drive the third switch unit or the fourth switch unit; wherein the active circuit comprises a DC-to-DC converter including input terminals electrically coupled to two terminals of the capacitor, and output terminals electrically coupled to the driving circuit.