Patent ID: 9094009
Filing Date: 2015-07-28
Classification: G01R,H02J,H02M,H03K,Y02E

Abstract:
1. A method of opening a shunt switch ( 8 , 9 , 10 , 11 ) carrying a current, the switch being connected in parallel with at least one thyristor ( 4 , 5 , 6 , 7 ) of a high voltage DC network, interruption of the current flowing through the switch being initiated at the time of a current zero of the current flowing through the switch, the method being characterized in that it includes, based on a measurement effected by means (M) for measuring the current flowing through the switch, a step of adjusting a control angle of the thyristor to position the current zero in a zone in which the time derivative of the measured current is a continuous function and the absolute value of a peak value of the measured current is substantially equal to the absolute value of the inaccuracy of the measurement of the current zero.