窄带低压电力线信道的阻抗测量与特性分析

为了获取低压电力线信道的阻抗特性随频率、时间、接入位置等变化的特点,采用比值法的原理,自行设计阻抗测量电路,选取我国实行电力用户用电信息采集系统的典型台区,对9～500kHz窄带低压电力线信道的阻抗进行了大量的测量,并利用MATLAB对所测数据进行处理计算及特性分析,分析结果表明:在9～500kHz频段内,阻抗随频率的升高呈上升趋势;不同接入点具有不同的阻抗特性;阻抗具有一定的时变性;阻抗受电网结构及负载类型、数量的影响较大。

Measurement and research of impedance characteristics of low voltage power networks of narrow-band

To obtain the features of how the impedance of low voltage power line channel varies with frequency,time and location,according to the principle of ratio method,an impedance measurement circuit is designed.The impedance of low voltage power line in 9~500 kHz is measured abundantly in some domestic typical transformer districts which the electricity consumption information gathering system is processed.According to the analysis of measurement results,it shows that within the frequency band from 9 kHz to 500 kHz the impedance of low voltage power line decrease with the increment of frequency generally.And the impedance varies following the different measurement points.The impedance which is time-variant can be affected by the Grid structure and the type of load.