A method for controlling the current profile for current supplied to each phase of a poly-phase switched reluctance motor when a respective phase of the motor is active. The interval each motor phase is active is determined as a function of motor operating conditions, as is a desired profile of current flow into and out of a phase winding (W) associated with the phase. The current profile has an initial portion (Z1) in which current flows into the winding from an initial value current value to a peak current value (I.sub.p). It also has a terminal portion (Z3) including current cut-off to the winding with current in the winding being either stored or dissipated prior to the phase becoming inactive. There may also be an intermediate portion (Z2) occurring between attainment of the peak current and the beginning of the terminal portion of the current profile. Current flow to the winding starts at the beginning of the initial portion of the phase, and current flow to the phase winding is cut-off prior to the end of the phase. Termination of current flow to the phase winding normally causes ringing in the motor because of the abrupt transition in current flow which occurs at current cut-off. However, according to the invention, current flow to the phase winding is now controlled throughout the active portion of the phase in accordance with the predetermined current profile. This includes determining the slope of current ramp-up during the initial portion of the profile until the peak current level is achieved; and, curvature of the current profile subsequent to cut-off of current flow to the phase winding. The current profile is controlled such that the slope of curvature of the profile immediately prior to current cut-off corresponds to the slope thereof immediately after cut- off. As a result, there is no transition in the current profile at current cut-off, and no ringing is produced in the motor by terminating current flow to the phase winding.
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