一种特殊异常工况下的并网非同期保护方法及系统
By monitoring the six-phase voltage phasor difference and multiple criteria after the circuit breaker is closed, the system identifies the abnormal state of non-synchronous grid connection and trips the circuit breaker quickly, thus solving the problem of false grid connection caused by the disconnecting switch not being closed properly and protecting electrical equipment from damage.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SANXIA JINSHAJIANG YUNCHUAN HYDROPOWER DEV CO LTD
- Filing Date
- 2026-04-03
- Publication Date
- 2026-07-17
AI Technical Summary
Existing technologies cannot effectively identify and handle "false grid connection" caused by the isolating switch not being fully closed but the position contact falsely reporting. This results in the inability to monitor the actual system status after the circuit breaker is closed, which in turn leads to problems such as isolating switch gap breakdown, inrush current, and arc erosion of equipment.
By monitoring the phasor difference of the six-phase voltage on both sides after the circuit breaker is closed in real time, and combining multiple criteria such as negative sequence voltage and effective voltage value, the grid connection non-synchronous abnormal state is identified within a preset time window, and the primary electrical equipment is quickly tripped for protection.
It enables accurate identification and rapid disconnection of "false grid connection" status, avoids equipment damage, improves the accuracy and reliability of protection, and prevents misjudgment caused by transient fluctuations and single-phase interference.
Smart Images
Figure CN121965448B_ABST