FIELD: electricity.
SUBSTANCE: invention relates to automatics of electric circuits and is intended to monitor variation of condition of head circuit breaker equipped with automatic reconnection device (ARD) of single-time action and installed in line of circular network supplied from buses of double-transformer substation. According to proposed method, from the moment of detection of short circuit current surge in the beginning of sectional line of circular network, time is counted equal to time of actuation of protection of line head circuit breaker, at the same time moment of short circuit current surge termination is monitored, and if the moment of time count termination coincides with the moment of disconnection of the first short circuit current surge, then fact of disconnection of head circuit breaker is confirmed, and then, from the moment of disconnection of the first short circuit current, time count is started for delay of automatic reconnection (ARD) of head circuit breaker, as well as count of total time equal to time of head circuit breaker ARD delay and time of actuation of its protection with acceleration, at the same time appearance of the second current surge is monitored, and if at the moment of ARD delay time count termination the second current surge is not available with value of more than normal working value, but less than short circuit current or equal to short circuit current, then fact of failure of ARD of head circuit breaker of circular network line, or at the moment of termination of time of ARD delay, the second current surge is detected with value of more than normal working value, but less than short circuit current, then fact of successful ARD of head circuit breaker of circular network line is established, and if the second short circuit current surge is detected at the moment of termination of ARD delay time count, then fact of failure of ARD of head circuit breaker of circular network line is established, and further if after appearance of the second short circuit current surge, at the moment of termination of total time count there is no disconnection of the second short circuit current surge, then fact of failure of head circuit breaker is established during reconnection.
EFFECT: expansion of functional capabilities of method by obtaining information about disconnection, successful, unsuccessful or failed ARD of head circuit breaker, and also failure of disconnection in case of its repeated connection for short circuit current.
5 dwg
