采样同步误差引起智能站母差保护异常的概率模型

针对采样同步误差可能引起母差保护误动拒动的问题,建立了采样同步误差下母差保护误动和拒动概率模型,以此评估采样同步误差对母差保护的影响。在各种因素干扰下,如温度、电磁干扰等,采样同步误差具有正态分布特点,会进一步影响母差保护判据的可靠性。据此建立了采样同步误差下的母差保护误动拒动概率模型。大量仿真结果表明,所建立的概率模型具有合理性和有效性。母差保护受同步误差的影响程度随采样同步误差增大而增大;基于电流相量的母差保护受采样同步误差的影响比基于电流采样值的母差保护要小。最后,为减小采样同步误差对母差保护的影响提出了一些合理化建议。

Probabilistic Model for Bus Differential Protection Failure Caused by Sampling Synchronization Error in Smart Substation

Sampling synchronization error may cause the misoperation and rejection of bus differential protection.It is subject to normal distribution when interfered by temperature,electromagnetism and other factors.Such phenomena affect the reliability of the criterion of bus differential protection.Considering that,this paper proposed a probabilistic model to evaluate the influence of sampling synchronization error on bus differential protection.Many simulation results verify that the proposed model is reasonable and effective.The influence on bus differential protection increases with the growth of synchronization error.The current-phasor-based bus differential protection is less affected by sampling synchronization error than the sampled-value-based bus current differential protection does.Finally,this paper provides some suggestions in reducing the impact of sampling synchronization error on bus differential protection.