Patent ID: 7271566

Claim:
A method for managing a voltage on a DC bus of a speed controller for an AC electric motor linked to a current distribution network, the controller comprising on its DC bus electronic circuits and operating according to a voltage control law of U/F type in which an internal ramp of acceleration/deceleration of the motor, having an initial slope of determined value, is inserted between a reference frequency imposed as input of the control law of the speed controller and a frequency of the stator obtained as output of this law, the method comprising: 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 the 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.