Patent ID: 8400088

Claim:
A controller for controlling a salient-pole machine, the controller being adapted for determining a steady-state voltage V 0 of phases of the salient-pole machine and comprising a calculating unit for calculating test pulse properties for test pulses for supply to phase inputs of the salient-pole machine, the test pulse properties comprising a pulse width, wherein the calculating unit is adapted for determining the pulse width in an adaptive manner, a current response receiving means for receiving a current response in reply to the test voltage pulses supplied to the phases of the salient-pole machine and a processing means for deriving an operational parameter of the salient-pole machine based on the current response, wherein the calculating unit is adapted for calculating test voltage vectors V 1 , V 2 for consecutive test pulses, each test voltage vector deviating from the steady-state voltage V 0 by a respective voltage deviation ΔV i , ΔV 2 , wherein the test voltage vectors V 1 , V 2 are determined in such a manner that ΔV 1 is at least substantially equal to −ΔV 2 , the controller not requiring an estimation of the induced voltage.