Motor soft-starter control

A method for controlling a motor soft-starter for starting an electric motor on a three-phases electric network, the soft starter comprising three arms, each arm comprising two thyristors in antiparallel configuration and each arm connecting a respective phase of the electric network to a respective winding of the electric motor, the method comprising:

• determining a misbalance between the three phases of the electric network;
• computing a first firing angle for the thyristors of a first arm of the three arms based on the determined misbalance between the three phases;
• and
• applying a trigger pulse on a specific thyristor of the first arm at the first firing angle.