Three-level power converter and power unit thereof

A power unit comprising a power switch module and a laminated busbar structure, wherein,

• the power switch module comprising:
• a first power semiconductor switch module having a first terminal, a second terminal and a third terminal;
• a clamping diode module having a first terminal, a second terminal and a third terminal;
• and
• a second power semiconductor switch module having a first terminal, a second terminal and a third terminal;
• the laminated busbar structure comprising a third busbar layer, a second busbar layer and a first busbar layer laminated on the power switch module;
• wherein,
• the first busbar layer electrically connects to the third terminal of the clamping diode module;
• the second busbar layer electrically connects to the second terminal of the first power semiconductor switch module and the first terminal of the second power semiconductor switch module respectively;
• the third busbar layer comprises a first sub-busbar, a second sub-busbar, a third sub-busbar and a fourth sub-busbar;
• the first sub-busbar electrically connects to the first terminal of the first power semiconductor switch module;
• the second sub-busbar electrically connects to the third terminal of the first power semiconductor switch module and the first terminal of the clamping diode module respectively;
• the third sub-busbar electrically connects to the second terminal of the clamping diode module and the third terminal of the second power semiconductor switch module respectively;
• and
• the fourth sub-busbar electrically connects to the second end of the second power semiconductor switch module.