摘要 |
FIELD: heavy-current power engineering. ^ SUBSTANCE: proposed method for switching heavy-current DC circuits involves following procedures. Prior to switching DC currents in heavy-current circuit incorporating vacuum contactor additional current supply is connected to this contactor through controlled vacuum spark-gap tube. Current pulse is passed from additional current supply through vacuum contactor upon turning on controlled vacuum spark-gap tube so that direction of this pulse is opposite to that of switching current and its peak value exceeds switching current by no more than 5 kA. Then vacuum contactor electrodes are set apart through desired distance; then, after electric strength of contactor electrode-to-electrode gap is recovered, controlled vacuum spark-gap tube is turned on by reducing current flowing through it to zero at its zero value approaching rate not over 200 A/mus. ^ EFFECT: facilitated procedure of switching in heavy direct-current circuits. ^ 1 cl, 1 dwg |