Inverter with capacitor discharge and cooling system
A system is shown for cooling components of an inverter. In one example, an inverter comprises a first compartment including a direct current (DC) link capacitor that is electrically coupled to a discharge resistor; and a thermal pad in contact with the DC link capacitor; a cooling system configured to circulate coolant through a housing adjacent to the thermal pad; and a noise filtering ferrite element coupled to a DC bus bar. A cooling plate may be further included between the DC link capacitor and the thermal pad and during a during a first condition when the inverter is operating, heat is transferred from the DC link capacitor to the cooling system; and during a second condition when the inverter is not operating, heat is reduced in the DC link capacitor by discharging electricity stored in the DC link capacitor via the discharge resistor.
1. An inverter, comprising: a first compartment including: a direct current (DC) link capacitor that is electrically coupled to a discharge resistor; and a thermal pad in contact with the DC link capacitor; a cooling system configured to circulate coolant through a housing adjacent to the thermal pad; a noise filtering ferrite element coupled to a DC bus bar; and further comprising a cooling plate arranged at a surface of the DC link capacitor between the DC link capacitor and the thermal pad.
2. The inverter of claim 1 , wherein the cooling plate is manufactured out of aluminum.
3. The inverter of claim 1 , wherein the cooling plate includes a portion positioned between the DC link capacitor and the cooling system, and a portion positioned between other components of the inverter and the cooling system.
4. The inverter of claim 1 , wherein the coolant is directly routed from an inlet of the inverter to a plurality of coolant conduits of the cooling system arranged adjacent to a side of the DC link capacitor, the plurality of coolant conduits and the side of the DC link capacitor separated by the cooling plate.
5. The inverter of claim 1 , wherein the DC link capacitor is electrically coupled to the discharge resistor via an electrical spring connector.
6. The inverter of claim 1 , wherein the DC link capacitor is electrically coupled to the discharge resistor via one or more bar busses between a DC bus bar of the inverter and a control circuit board of the inverter.
7. The inverter of claim 1 , wherein the discharge resistor is in thermal contact with a housing of the invertor via a thermal pad.
8. The inverter of claim 7 , wherein the discharge resistor is positioned within a recess of the thermal pad, the recess designed to increase an amount of heat transferred from the discharge resistor to the housing.
9. The inverter of claim 7 , wherein sections of the thermal pad are in contact with a lower surface of a control circuit board.
10. The inverter of claim 1 , wherein the discharge resistor is configured to passively discharge without any control inputs.
11. The inverter of claim 1 , further comprising a second compartment including a control circuit board, wherein the first and second compartment have varying levels of electromagnetic interference (EMI).
12. The inverter of claim 1 , further comprising a third compartment with external communication components positioned therein, wherein the first, second, and third compartment have varying levels of EMI.
13. A cooling system for an inverter, the cooling system comprising: a plurality of coolant conduits through which a coolant is directed to transfer heat out of the inverter, the plurality of coolant conduits adjacent to a surface of a direct current (DC) link capacitor of the inverter; and a discharge resistor electrically coupled to the DC link capacitor; wherein during a first condition when the inverter is operating, heat is transferred from the DC link capacitor to the plurality of coolant conduits; and during a second condition when the inverter is not operating, heat is reduced in the DC link capacitor by discharging the DC link capacitor via the discharge resistor; wherein heat is transferred from the DC link capacitor to the plurality of coolant conduits via a thermal pad and wherein a cooling plate is included between the surface of the DC link capacitor and the thermal pad.
14. The cooling system of claim 13 , wherein the DC link capacitor and thermal pad are enclosed within a first compartment of the inverter, a control circuit board is enclosed within a second compartment of the inverter, and external communication components of the inverter are enclosed within a third compartment of the inverter, the first, second, and third compartments having varying levels of electromagnetic interference (EMI).
15. The cooling system of claim 13 , wherein the DC link capacitor is electrically coupled to the discharge resistor via one of an electrical spring connector and a bar bus positioned between a DC bus bar of the inverter and a control circuit board of the inverter.
16. An inverter, comprising:
a plurality of compartments enclosing different components of the inverter, each compartment of the plurality of compartments having a different level of electromagnetic interference (EMI);
wherein one compartment of the plurality of compartments includes a direct current (DC) link capacitor electrically coupled to a discharge resistor, the DC link capacitor positioned adjacent to a cooling system, a surface of the DC link capacitor separated from a surface of the cooling system by a cooling plate and a thermal pad.
17. The inverter of claim 16 , wherein the cooling system comprises a plurality of coolant conduits through which a coolant is flowed, the coolant entering the inverter via a coolant inlet of the inverter and exiting the inverter via a coolant outlet of the inverter.