基于改进差分法的TA暂态饱和识别方法研究

Study on TA Transient Saturation Identification based on the Improved Differential Method

电流暂态饱和引起的继电保护不正确动作事故频发,暂态饱和正确识别及不饱和数据段提取是继电保护采取抗暂态饱和影响措施的关键技术。分析了TA暂态饱和对继电保护的影响,总结了现有的继电保护抗TA暂态饱和措施;分析了基本差分法饱和检测原理,结合电压模值判据以及退出饱和附加判据提出了改进差分法,可准确识别TA进出饱和时间;结合TA暂态饱和试验数据,验证了改进差分法进行TA饱和检测的有效性。

Current transient saturation leads to frequent incorrect actions of relay protection. Correct identification of transient saturation and extraction of unsaturated data segment is the key relay protection technology to prevent transient saturation effects. This paper studies the influence of TA transient saturation on the power system relaying and summarizes the existing current repressive measures in practice. The principle of the basic differential method for identifying TA transient saturation is analyzed. Based on the voltage module criterion and the additional criterion for identifying exiting saturation, the improved differential method is proposed, with which the timing of entering and exiting saturation can be identified accurately. Finally, the data from TA saturation experiment have verified the effeetiveness of the improved differential method.