关于厂用电源快切装置切换判据的探讨

在分析母线残压与备用电源电压之间相位差变化的基础上,介绍了适用于厂用电源切换的理论判据,采用对相位差实时测量和预判的方法确定最佳合闸时刻。求出快速切换时最大允许相位差为63°;考虑断路器合闸时间,针对正常、事故、低压、误跳串联切换方式以及正常同时、事故同时、低压同时切换方式2种情况,分别提出了相应的快速切换理论判据。同期捕捉切换以相位差为0°时作为合闸目标,考虑断路器合闸时间,得出其理论判据。慢速切换判据只需母线残压低于设定的最大允许残压。理论分析和现场运行证明了其可行性和有效性。

Discussion on criterions of station power transfer device

Based on the analysis of the phase difference between bus residual voltage and stand-by power supply voltage,the theoretic criterions for station power transfer are introduced. The real -time measurement of phase difference and advance-judgement are used to determine the optimal closing time. The maximum permissible phase difference for fast transfer is calculated to be sixty -three degrees. To take the closing time of breaker into account,the fast transfer criterions are presented for two conditions:one is the normal,faulty,low voltage,miss trip serial transfer modes;the other is the normal,faulty,low voltage simultaneous transfer modes. The synch capture transfer regards zero phase difference as its object,and its theoretic criterion is put forward with conside-ration of breaker closing time. While the slow transfer criterion is only the bus residual voltage being less than the set maximum permissible residual voltage. The theoretic analysis and practical applications manifest their feasibility and validity.