Inverter AC bus bar assembly
Power inverter assemblies are provided herein for use with motor vehicles. An inverter assembly may have a symmetrical structure configured to convert DC input power to AC output power. The inverter assembly may include a housing enclosing a symmetrical DC input portion, a symmetrical AC output portion, a DC link capacitor, and a gate drive portion having a pair of power modules. The symmetrical DC input portion can include a DC input bus bar sub-assembly to which the DC link capacitor is coupled, and a second DC bus bar sub-assembly that may electrically couple the DC link capacitor with the power modules. The symmetrical AC output portion may include a three phase output AC bus bar sub-assembly to which the power modules can be electrically coupled. A cooling sub-assembly may be provided for cooling the power modules with fluid transfer using a coolant.
1. A three phase output AC bus bar sub-assembly for an inverter assembly, the three phase output AC bus bar sub-assembly connected to a first power module and a second power module each having three output terminals, the three phase output AC bus bar sub-assembly comprising:
a first bus bar comprising a first bus bar body having a front surface and a back surface, the first bus bar comprising a first power module tab and a second power module tab extending from the back surface of the first bus bar body, the first bus bar comprising a first output tab extending from a proximal end of the first output tab at the front surface of the first bus bar to a distal end of the first output tab laterally aligned with the proximal end of the first output tab;
a second bus bar comprising a second bus bar body having a front surface and a back surface, the second bus bar comprising a third power module tab and a fourth power module tab extending from the back surface of the second bus bar body, the second bus bar comprising a second output tab extending from a proximal end of the second output tab at the front surface of the second bus bar body to a distal end of the second output tab laterally offset from the proximal end of the second output tab; and
a third bus bar comprising a third bus bar body having a front surface and a back surface, the third bus bar comprising a fifth power module tab and a sixth power module tab extending from the back surface of the third bus bar body, the third bus bar comprising a third output tab extending from a proximal end of the third output tab at the front surface of the third bus bar body to a distal end of the third output tab laterally aligned with the proximal end of the third output tab,
wherein the first power module tab of the first bus bar connects with a first output terminal of the first power module and wherein the second power module tab of the first bus bar connects with a first output terminal of the second power module to output a first phase of an AC power signal generated by the first and second power modules,
wherein the third power module tab of the second bus bar connects with a second output terminal of the first power module and wherein the fourth power module tab of the second bus bar connects with a second output terminal of the second power module to output a second phase of the AC power signal generated by the first and second power modules,
wherein the fifth power module tab of the third bus bar connects with a third output terminal of the first power module and wherein the sixth power module tab of the third bus bar connects with a third output terminal of the second power module to output a third phase of the AC power signal generated by the first and second power modules,
wherein the first bus bar body of the first bus bar is positioned behind the second bus bar body of the second bus bar and the third bus bar body of the third bus bar is positioned in front of the second bus bar body of the second bus bar, and
wherein the distal end of the first output tab and the distal end of the third output tab are spaced equidistantly from the distal end of the second output tab when the first, second, and third bus bars are placed into mating relationship with one another.
2. The three phase output AC bus bar sub-assembly according to claim 1 , wherein the front surface of one or more of the first, second and third bus bars includes an insulating layer.
3. The three phase output AC bus bar sub-assembly according to claim 1 , further comprising an insulating spacer disposed between the front surface of the first bus bar and the back surface of the second bus bar, and another insulating spacer disposed between the front surface of the second bus bar and the back surface of the third bus bar.
4. The three phase output AC bus bar sub-assembly according to claim 1 , further comprising a mounting plate that is coupled to the second bus bar and the third bus bar.
5. The three phase output AC bus bar sub-assembly according to claim 4 , wherein the first, second, and third output tabs extend through the mounting plate, and wherein the first, second, third, fourth, fifth, and sixth power module tabs are aligned with one another along a longitudinal axis of alignment.
6. The three phase output AC bus bar sub-assembly according to claim 1 , wherein each of the first, second, and third output tabs is disposed on a lower end of the corresponding bus bar body and each of the first, second, third, fourth, fifth, and sixth power modules tabs is disposed on an upper end of the corresponding bus bar body.
7. The three phase output AC bus bar sub-assembly according to claim 1 , wherein the second bus bar is laterally offset from the first bus bar and the third bus bar is laterally offset from the second bus bar.
8. The three phase output AC bus bar sub-assembly according to claim 1 , wherein each the first, second and third bus bars is configured to carry a unique phase of an AC power signal generated by the plurality of power modules.