摘要
为有效评估低压配电台区用电环境对电力线载波信号的影响,介绍低压电力线信道传输特性测量方法。首先对信道传输特性的测量参数及设备进行介绍,给出了低压电力线噪声、信号传输损耗、电力线阻抗特性的测量原理,并用测试设备对低压电力线信道进行特性测量,给出测量结果。实验结果表明:环境噪声在中、低频段处较大,线路衰减在220 kHz频点左右最为严重,而测试信号在高频区域的阻抗特性在工频过零时刻时呈现稳定特性。由各项指标可知,低压电力线载波信号传输的最佳频率范围为350~450 kHz;电压过零点处低压电网呈现阻抗高且稳定、噪声电平低的特性,适用于信号传输,并有利系统时间同步。
This paper presents a channel measurement method for low-voltage power networks.Firstly,the measurement parameters and equipments for the channel transmission characteristic are introduced.Then the basic principles for measuring noise,attenuation and impedance characteristics are analyzed.At the end,we give the measurement and the analysis results.It shows that the noise is larger when the frequency is low and medium,and the line attenuates seriously when the frequency is 220 kHz,as well as that the impedance characteristics is stable when the power frequency nearby zero in the high-frequency regions.Thus,we can conclude that the optimal transmission frequency is between 350 ~450Khz.Besides,the noise is low and the impedance is stable when power frequency nearby zero.It means that when power frequency is nearby zero the carrier communication may have the best result,also,this scheme is beneficial to the system synchronization.
出处
《实验室研究与探索》
CAS
北大核心
2017年第1期136-139,143,共5页
Research and Exploration In Laboratory
基金
贵州省科技厅基金项目(黔科合LH[2014]7614)
贵州电网科技项目GZ2014-2-0006资助
关键词
低压电力线
信道测量
噪声特性
阻抗特性
衰减特性
low-voltage power lines
channel measurement
noise characteristics
attenuation characteristics
impedance characteristics
