Patent ID: 9442029
Filing Date: 2016-09-13
CPC Classification: B62D,G01L,H02P

Claim Text:
1. A method of estimating shaft torque of an alternating current machine, the method comprising: determining phase current command values; estimating terminal voltage values based on actual phase current values and based on at least one of a duty cycle and a dead time ratio of the machine; transforming the terminal voltage values to derive direct and quadrature voltage representations consistent with the current command values; determining a terminal power of one or more terminals of the machine, the terminal power directly based on the direct and quadrature voltage representations of the machine and the current command values; determining an estimated shaft torque of the machine based on the terminal power in accordance with at least one efficiency value based on machine parameters from a characterization of the machine; and adjusting a torque command applied to the machine based on the estimated shaft torque.