FIELD: electricity.
SUBSTANCE: since the moment of first short circuit current inrush there measured is its time period, this time is compared to delay time of protection operation of main switches of all lines going from substation buses, in case of lines matching the disconnected main switch is installed. Since the moment of cut off of first short circuit current inrush the time is counted, the time should be equal to delay time of automatic reclosure, cut off main switch, note that the second short circuit current inrush appearance is controlled and if it occurs in the moment of counted time finish, then the fact of repeated engagement of this switch at short circuit is stated and simultaneously the delay time of protection operation with acceleration of cut off switch is counted together with delay time of protection operation of local switch. The second current inrush of short circuit disconnection is controlled. If in the moment of ending of delay time of protection operation with acceleration there is no short circuit current cut off, the fact of its repeated disengagement failure is stated; if in the moment of ending of delay time of protection operation of local switch the second current inrush of short circuit is cut off, the fact of its disconnection is stated.
EFFECT: enlarging functional capabilities.
2 dwg
Authors
Dates
2012-06-27—Published
2011-05-03—Filed