Abstract: A system includes a battery configured for providing electrical energy in direct current and a drive unit configured for utilizing electrical energy in alternating current to provide an output torque. The system includes a power inverter configured for receiving the electrical energy in direct current, transforming the electrical energy to alternating current, and providing the electrical energy in alternating current to the drive unit. The power inverter includes a direct current bus bar. The system includes a computerized controller. The controller monitors an environmental temperature of the inverter and monitors a current flow of the electrical energy received by the inverter. The controller determines an estimated temperature of the bus bar based upon the environmental temperature and the current flow and determining an inverter percent available capability based upon the estimated temperature.

Abstract: A system for controlling operation of a vehicle having a power inverter module includes an alternating current (AC) power bus coupled to the power inverter module. The AC power bus has a plurality of busbars for conducting an AC current having multiple phases. The AC power bus is coupled to a stator in an electric motor configured to generate torque to propel the vehicle. A controller is adapted to determine an estimated temperature of the AC power bus for the multiple phases based on a plurality of factors. The plurality of factors includes an oil flow rate of a motor oil and a coolant flow rate of an inverter coolant that are in respective direct or indirect thermal contact with the plurality of busbars. The controller is adapted to control operation of the vehicle based in part on a highest one of the estimated temperature of the multiple phases.

Abstract: An electric drive system includes a direct current (DC) power supply, a rotary electric machine connectable to a load, a power inverter module (PIM), and a controller. The PIM includes a bulk capacitor connected to the DC power supply, along with a plurality of power switches. Each power switch has an output side connected to the electric machine and an input side connected to the bulk capacitor. The controller executes a method to estimate an internal temperature of the bulk capacitor as an estimated internal temperature. This occurs in response to an enabling condition. The controller then selectively derates the electric machine in response to the estimated internal temperature.

Abstract: A system includes a battery configured for providing electrical energy in direct current and a drive unit configured for utilizing electrical energy in alternating current to provide an output torque. The system includes a power inverter configured for receiving the electrical energy in direct current, transforming the electrical energy to alternating current, and providing the electrical energy in alternating current to the drive unit. The power inverter includes a direct current bus bar. The system includes a computerized controller. The controller monitors an environmental temperature of the inverter and monitors a current flow of the electrical energy received by the inverter. The controller determines an estimated temperature of the bus bar based upon the environmental temperature and the current flow and determining an inverter percent available capability based upon the estimated temperature.