电力线信道通信特性影响因素分析

Analysis of the factors influencing the communication characteristics of power line channel

电力线为传输电能而设计,复杂的配电网拓扑结构使得电力线通信信道环境恶劣,信道特性变化规律复杂,严重影响信号传输的质量和效率。为应对上述问题,利用传输线二端口网络,建立电力线信道的数学模型,进而仿真分析电网结构及网络参数对信道电压幅频特性以及网络输入阻抗特性的影响。通过分析发现,信号衰减峰谷值的位置受主线路长度的影响较小,分支线路长度影响信号衰减峰谷个数。并且,信道电压传输幅频特性的衰减峰频率处,网络的输入阻抗值相等。

The power line is designed for the electricity transmission. The complicated distribution network topology induces the deteriorated communication channel and complex channel characteristics of the power line, which deteriorates the quality and efficiency of the signal transmission. To deal with the above problems, the mathematical model of the power line channel is established by utilizing the two-port network of the transmission line. Based on the model, it is simulated and analyzed that the influence of the power network structure and network parameters on magnitude-frequency characteristics of the channel voltage and network input impedance. It is found that in the magnitude-frequency characteristics, the peak and valley positions have a low correlation with the length of the main line, and the number of the peak and valley has a high correlation with the length of the branch line. Besides, the input impedance of the network is equal at the peak frequency.