Optimization of switching frequency and pulse width modulation technique for traction power inverters
AssigneeBorgWarner Inc.
InventorsHassan H. Eldeeb, Ujjwal Kumar, Ronald J. Krefta, Caleb W. Secrest
Life of this patent
Estimating the term…
Abstract
A method of operating a power inverter for an electric machine includes selecting an inverter switching technique; determining a frequency range for inverter switching; determining a direct current (DC) voltage range for inverter switching; determining an optimal switching map including an inverter switching technique and frequency selection for each value of torque-speed on a torque-speed curve; and controlling switches included in the power inverter using the optimal switching map.
Claims16
A method of operating a power inverter for an electric machine, comprising the steps of:
- (a) selecting an inverter switching technique;
- (b) determining a frequency range for inverter switching;
- (c) determining a direct current (DC) voltage range for inverter switching;
- (d) determining a maximum efficiency at each torque-speed value along the torque-speed curve based on an alternating current (AC) ripple;
- (e) determining an optimal switching map including an inverter switching technique and frequency selection for each value of torque-speed on a torque-speed curve;
- and
- (f) controlling switches included in the inverter using the optimal switching map.
A method of operating an inverter for an electric machine, comprising the steps of:
- (a) selecting an inverter switching technique;
- (b) determining a frequency range for inverter switching;
- (c) determining a direct current (DC) voltage range for inverter switching;
- (d) measuring performance of the electric machine at a selected inverter switching technique and a determined frequency range;
- (e) determining an inverter power loss at a torque-speed value along a torque speed curve;
- (f) determining a maximum efficiency at each torque-speed value along the torque-speed curve based on inverter switching technique and switching frequency;
- (g) determining an optimal switching map including an inverter switching technique and frequency selection for each value of torque-speed on a torque-speed curve based on step (d);
- and
- (h) controlling switches included in the inverter using the optimal switching map.
A power inverter for controlling an electric machine, comprising:
- a control system configured to select an inverter switching technique;
- determine a frequency range for power inverter switching;
- determine a direct current (DC) voltage range for power inverter switching;
- determine a maximum efficiency at each torque-speed value along the torque-speed curve based on an alternating current (AC) ripple;
- determine an optimal switching map including an inverter switching technique and frequency selection for each value of torque-speed on a torque-speed curve;
- and control switches included in the power inverter that are configured to electrically connect to the electric machine and the battery using the optimal switching map.
Dependencies are inferred from the claim text.