中文摘要：

在电子式互感器应用环境中,需要在保持各站采样时钟独立性的前提下,完成采样数据站间同步.文中提出了时域连续有限冲激响应（TCFIR）滤波器的概念,并以此为基础构造了连续数字低通滤波器,从电子式互感器输出的离散采样数据恢复出连续信号,重新计算出任意时刻的采样值.用含丰富谐波信号的500kV线路故障电流进行的仿真和时域、频域分析表明,1 000 Hz、2 400 Hz和4 000 Hz的采样频率下,该算法在数据窗长6个采样间隔（延时为3个采样间隔）时,其有效值和DFT基波幅值误差均小于0.4%,精度和实时性能够满足继电保护和分布式稳定控制的要求.

英文摘要：

Under electronic instrument transducer application circumstance, sampling data synchronization between substaions should be achieved as sampling clocks of substations keep independent. This paper presents the concept of time-domain continuous finite impulse response（TCFIR） filter to solve this problem. A TCFIR based continuous digital low pass filter was constructed to acquire continuous signal from EPT/ECT discrete output data and calculate sampling value at any moment. Simulation and time-frequency domain analysis using 500kV transmission line fault current with strong harmonic was carried out, With 1000Hz, 2400Hz an.d 4000Hz sampling frequency, the RMS and DFT fundamental amplitude error is less than 0.4%. Meanwhile, the arithmetic data window length is 6 points and the time delay is only 3 sampling intervals. The result shows that the arithmatic meets the accuracy and realtime requirement of protection and distributed stability control application.