A particularly flexible method for measuring current in each phase of a three phase inverter driven motor, controlled in PWM mode by three PWM signals, employing a single common DC-link current sensing resistor on which intermittently sampling the current includes a relatively simple determination of the modulation index for the voltage demand set by the motor controller and of specific mutual duty cycle conditions of the three PWM phase driving signals and by a consequent choice of the way "sampling windows" of sufficient duration for allowing to sample distinctly two phase currents are provided for optimal performance.
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