A method and system for managing the voltage of a DC bus of a speed controller for an AC electric motor linked to a current distribution network. The method includes comparing a value of the voltage measured on the DC bus with a determined limit value, when the value of the voltage measured on the DC bus becomes greater than the limit value, forcing the slope of an internal ramp to a zero value so as to confer a constant frequency on the stator, and when the value of the voltage measured on the DC bus again becomes less than the limit value, progressively increasing the value of the slope of the internal ramp.