Heat dissipation system of power module

The invention discloses a heat dissipation system of a power module, and the system comprises a radiator which is provided with a cooling cavity with an open side; the heat dissipation substrate is connected with the heat dissipater to seal the open side of the cooling cavity, the heat dissipation substrate is provided with heat dissipation pin fins, the heat dissipation pin fins extend into the cooling cavity, the number of the heat dissipation pin fins is multiple, the heat dissipation pin fins located at the outlet area of the cooling cavity are provided with polygonal cross sections, and the polygonal cross sections of the heat dissipation pin fins extend into the cooling cavity. And an acceleration flow guide structure is arranged in an outlet area of the cooling cavity. According to the heat dissipation system of the power module, the radiator and the heat dissipation substrate are assembled for use, so that the flow rate of the cooling medium at the outlet area of the cooling cavity can be increased, n