T接线路差动保护中电容电流补偿方法研究

电流差动保护的性能受线路电容电流的影响。根据T型输电线路的特点,提出了两种T接线路差动保护的电容电流补偿方法。两种方法均基于π型等效网络而提出,分别适用于不同的通道条件。理论分析和EMTP仿真计算表明,采用本文的电容电流补偿方法,能大大降低区外故障和线路空载合闸时的不平衡电流,从而降低动作门槛,大大提高保护的灵敏度和动作速度。

Study on current compensation method of differential protection for teed lines

The performance of differential current protection is influenced by capacitive current. According to the feature of the teed lines connection, this paper presents two current compensation methods of differential protection. The methods based on n equivalent network, respectively, applicable to different access condition. The theoretical analysis and EMTP simulation indicate that the compensation method can reduce the imbanlance current of external fault and unloaded switching, thereby reduce the action threshold and enhance the sensitivity and action speed of the protection greatly.