Enhanced integration of power inverters using polymer composite encapsulation
A power control system for an electric vehicle includes a power inverter comprising a switch module including a plurality of power switches, a controller board, and a gate driver board in communication with the controller board and configured to drive gates of the plurality of switches. A first housing is made of polymer composite, encloses the power inverter, defines a first cooling cavity in thermal communication with a first surface of the switch module, and encapsulates a portion of at least one of the switch module, the controller board and the gate driver board.
1. A power control system for an electric vehicle, comprising:
a power inverter comprising:
a switch module including a plurality of power switches;
a controller board; and
a gate driver board in communication with the controller board and configured to drive gates of the plurality of power switches;
a first housing made of polymer composite, enclosing the power inverter, defining a first cooling cavity in thermal communication with a first surface of the switch module, and encapsulating a portion of at least one of the switch module, the controller board and the gate driver board; and
a conductive layer arranged on greater than 80% of an outer surface of the first housing.
2. The power control system of claim 1 , wherein:
the polymer composite comprises a polymer composite including the polymer composite and fillers;
the first housing comprises greater than or equal to 50% of the polymer composite by volume;
the polymer composite has a coefficient of thermal expansion in a predetermined range from 10 to 30 ppm/° C.; and
the polymer composite has a dielectric strength that is greater than 20 kV/mm.
3. The power control system of claim 1 , wherein the first housing defines a second cooling cavity, wherein the second cooling cavity is in thermal communication with a second surface of the switch module.
4. The power control system of claim 3 , wherein the switch module is arranged between the first cooling cavity and the second cooling cavity.
5. The power control system of claim 4 , further comprising a DC bulk capacitor assembly including:
a bulk capacitor; and
first and second DC busbars,
wherein the bulk capacitor and the first and second DC busbars are encapsulated in the first housing.
6. The power control system of claim 1 , further comprising a DC bulk capacitor assembly including:
a bulk capacitor; and
first and second DC busbars,
wherein the bulk capacitor and the first and second DC busbars are encapsulated in a second housing made of polymer composite, and
wherein the second housing defines a second coolant cavity on an outer surface thereof that is in thermal communication with a second surface of the switch module.
7. The power control system of claim 6 , wherein at least one of the first cooling cavity and the second cooling cavity includes a coating on an inner surface thereof to reduce permeability of the first housing to coolant.
8. The power control system of claim 1 , further comprising AC busbars connecting the switch module to a load, wherein the first housing includes slots on an inner surface thereof to receive the AC busbars.
9. The power control system of claim 1 , wherein the first housing comprises vascular channels.
10. The power control system of claim 1 , further comprising conductive foam arranged on an inner surface of the first housing.
11. A power control system for an electric vehicle, comprising:
a housing made of a polymer composite and including a conductive outer coating arranged on an outer surface of the polymer composite,
a bulk capacitor assembly arranged in the housing and including a bulk capacitor and first and second DC busbars that are encapsulated in polymer composite; and
a power inverter arranged in the housing and comprising:
a switch module including a plurality of power switches;
a controller board; and
a gate driver board in communication with the controller board and configured to drive gates of the plurality of power switches; and
AC busbars connecting the switch module to a load.
12. The power control system of claim 11 , further comprising conductive foam arranged on an inner surface of the housing.
13. The power control system of claim 12 , wherein the conductive foam extends inwardly between the gate driver board and the bulk capacitor assembly.
14. The power control system of claim 12 , wherein the conductive foam extends inwardly between the bulk capacitor assembly and the controller board.
15. The power control system of claim 11 , wherein the housing comprises greater than or equal to 50% polymer composite by volume.
16. The power control system of claim 15 , wherein the polymer composite has a coefficient of thermal expansion in a predetermined range from 10 to 30 ppm/° C.
17. The power control system of claim 15 , wherein the polymer composite has a dielectric strength that is greater than 20 kV/mm.
18. The power control system of claim 11 , further comprising a shield arranged between at least one of:
the controller board and the AC busbars, and
the controller board and the bulk capacitor.
19. A power control system for an electric vehicle, comprising:
a power inverter including a controller board, a gate driver board, a switch module including a plurality of switches, and gate driver pins connected between the gate driver board and the switch module;
AC busbars connected to the switch module;
a first housing made at least partially of polymer composite, wherein:
the first housing defines a first cooling cavity and a first cooling channel configured for connection to an external coolant source;
at least one of the controller board and the gate driver board is encapsulated in the first housing; and
wherein the switch module includes a first surface in thermal communication with the first cooling cavity; and
a conductive layer arranged on greater than 80% of an outer surface of the first housing; and
a DC bulk capacitor assembly including:
a bulk capacitor; and
first and second DC busbars,
wherein the bulk capacitor and the first and second DC busbars are encapsulated in a second housing made of polymer composite, and
wherein the second housing defines a second coolant cavity on an outer surface thereof that is in thermal communication with a second surface of the switch module,
wherein the first housing comprises greater than or equal to 50% polymer composite by volume.
20. The power control system of claim 19 , wherein:
the polymer composite of the first housing has a coefficient of thermal expansion in a predetermined range from 10 to 30 ppm/° C., and
the polymer composite of the first housing has a dielectric strength that is greater than 20 kV/mm.