摘要
针对现有剩余电流保护装置存在的死区问题,提出了一种基于半波真有效值的故障电流检测方法。将总剩余电流相邻的两个完整周波离散化后等相位点相减,剔除总剩余电流中的正常剩余电流,保留得到故障电流波形。首先利用幅值绝对值累加的方法确定故障发生周波,接着计算故障发生周波之后的半个故障波形的真有效值,从而实现了故障电流有效值的获取。利用建模仿真以及触/漏电实验实测数据对所提出的方法进行了验证,证明了所提方法具有可靠性好、计算精度较高、有一定的抗噪声能力、响应时间短以及简便易行的优点,很适合工程实际应用,对新型剩余电流保护装置的开发有一定的参考价值。
Aimed at the problem that the existing protective methods all have protective dead - zones, a method to detect fault current based on the true RMS of the half wave is proposed. After discretization, sampling point subtract the same phase point of total residual current to remove the normal residual current on the total residual current and remain fault current. Firstly, the sum of the absolute values of the amplitude is used to determine the occurrence of the fault current. Then the true RMS value of the half fault waveform is calculated after the fault occurs, thus obtaining the effective value of the fault current. The method can calculate the RMS of the shock/leakage current. The simulation and experimental samples are used for verifica-tion. The results show that the method has the advantages of good reliability, high precision, high anti - noise ability, short response time and simple operation. It is very suitable for engineering application, and has a certain reference value for the de-velopment of new residual current protection device.
出处
《四川电力技术》
2017年第3期66-72,共7页
Sichuan Electric Power Technology
关键词
剩余电流保护技术
故障电流
幅值
真有效值
数字测量技术
residual current protection technology
fault current
amplitude
true RMS
digital measurement technology
