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| 摘要: |
| 在非全相运行期间,由于保护逻辑设置不当或通道等因素的影响,往往会导致高压输电线路纵联零序方向保护误动作。结合现场500kV电网中出现的某次故障事故,深入分析了事故中纵联零序方向保护误动作的原因:通信接口设备对允许信号的展宽;非全相运行时没有闭锁纵联零序保护。并详细描述了影响纵联零序方向保护正确动作的主要因素,有弱馈、非全相运行、分布电容、功率倒向、零序互感等。给出了防止纵联零序方向保护误动作的解决措施:非全相运行与零序功率倒向、逻辑的输出通过或门构成闭锁纵联零序保护;去掉接口装置对允许信号的展宽。现场运行结果证明了该解决措施的准确性和有效性。 |
| 关键词: 输电线路,纵联保护,零序,误动作 |
| DOI： |
| 分类号:TM773 |
| 基金项目: |
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| Analysis of longitudinal zero sequence direction protection misoperation and its countermeasures |
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WANG Ping CHEN Jiu-lin
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| Abstract: |
| If the protective logic setting is incorrect or the communication channel wrong,the longitudinal zero sequence direction protection of high voltage transmission line will operate improperly under non-complete phase operating condition.With an accident in 500 kV power network,an improper operation of the longitudinal zero sequence direction protection is analyzed:the enable signal is extended by the communication interface device and the longitudinal zero sequence protection is not blocked under non-complete phase operation.The main factors causing its improper operation are described in detail,i.e.week feeding,non-complete operation,distributed capacitance,inverse power direction,zero sequence mutual inductance,etc..The countermeasures are put forward:blocking the longitudinal zero sequence direction,protection by the OR gate output of the non-complete operation signal and inverse zero sequence power signal;removing the interface device to prevent extension of enable signal.Site operation shows that proposed countermeasures are correct and effect. |
| Key words: transmission line,longitudinal protection,zero sequence,misoperation |
