Power semiconductor cooling system

1. A cooling system for a power semiconductor switch, comprising:

a heat sink pressed against the power semiconductor switch;

a plenum comprising a plenum wall with a first opening therethrough, the heatsink being aligned with the first opening; and

a fan in communication with the plenum,

wherein the fan is configured to:

flow cooling air through or around the heat sink,

flow the cooling air through the first opening in the plenum wall and through the plenum, and

flow the cooling air out of or into the plenum,

wherein the heat sink comprises a first channel extending therethrough,

wherein the first channel being aligned with the first opening in the plenum wall, and

wherein the first channel is enclosed around a circumference thereof.

2. The cooling system according to claim 1 , wherein the heat sink is mounted to the plenum wall.

3. The cooling system according to claim 2 , wherein the plenum wall is made of an insulative material, the heat sink mounted to the plenum wall thereby being electrically isolated.

4. The cooling system according to claim 1 , further comprising a seal between the heat sink and the first opening in the plenum wall.

5. The cooling system according to claim 1 , wherein the first channel comprises cooling fins therein.

6. The cooling system according to claim 1 , wherein the fan is disposed at an outlet of the plenum.

7. The cooling system according to claim 6 , wherein the fan draws air from the heat sink into the plenum through the first opening in the plenum wall and out of the plenum.

8. The cooling system according to claim 1 , wherein the heat sink and the power semiconductor switch are disposed within a housing separated from the plenum, the fan generating negative pressure within the housing.

9. The cooling system according to claim 1 , further comprising a divider disposed between the fan and the plenum, the fan being disposed at an exhaust and the divider preventing exhaust air from bypassing the fan and reentering the plenum.

10. The cooling system according to claim 1 , further comprising at least two of the fan arranged side-by-side.

11. The cooling system according to claim 1 , wherein the heat sink and power semiconductor switch are disposed within a housing separated from the plenum, the housing having no fans therein.

12. A static transfer switch comprising the cooling system of claim 1 , wherein the power semiconductor switch electrically couples one of two power sources to a power output.

13. A three phase AC static transfer switch comprising the cooling system of claim 1 , and further comprising six of the power semiconductor switch and six of the heat sink, each heat sink being pressed against a respective power semiconductor switch, each of three of the power semiconductor switches electrically coupling respective phases of a first three phase power source to a power output, and each of three others of the power semiconductor switches electrically coupling respective phases of a second three phase power source to a power output.

14. A cooling system for a power semiconductor switch, comprising:

a heat sink pressed against the power semiconductor switch;

a plenum comprising a plenum wall with a first opening therethrough, the heatsink being aligned with the first opening; and

a fan in communication with the plenum,

wherein the fan is configured to:

flow cooling air through or around the heat sink,

flow the cooling air through the first opening in the plenum wall and through the plenum, and

flow the cooling air out of or into the plenum,

wherein the power semiconductor switch is pressed between two of the heat sink, the power semiconductor switch being smaller in width than each of the two heat sinks such that a second channel is formed between the two heat sinks and the power semiconductor switch, and further comprising a second opening through the plenum wall aligned with the power semiconductor switch.

15. A cooling system for a power semiconductor switch, comprising:

a heat sink pressed against the power semiconductor switch;

a plenum comprising a plenum wall with a first opening therethrough, the heatsink being aligned with the first opening;

a fan in communication with the plenum,

wherein the fan is configured to:

flow cooling air through or around the heat sink,

flow the cooling air through the first opening in the plenum wall and through the plenum, and

flow the cooling air out of or into the plenum; and

three of the heat sink and two of the power semiconductor switch, each of the power semiconductor switches being pressed between two of the heat sinks such that one heat sink is pressed between the two power semiconductor switches and two of the heat sinks are each pressed against an outer side of a respective one of the two power semiconductor switches.

16. The cooling system according to claim 15 , further comprising three of the first opening in the plenum wall, each of the first openings being aligned with a respective one of the heat sinks.

17. A cooling system for a power semiconductor switch, comprising:

a heat sink pressed against the power semiconductor switch;

a plenum comprising a plenum wall with a first opening therethrough, the heatsink being aligned with the first opening; and

a fan in communication with the plenum,

wherein the fan is configured to:

flow cooling air through or around the heat sink,

flow the cooling air through the first opening in the plenum wall and through the plenum, and

flow the cooling air out of or into the plenum; and

an electrical connector electrically coupled to the power semiconductor switch extending through the plenum wall, the plenum and a back wall of the plenum.