Research On Influences Of Reactive Power Compensator On The Characteristics Of Power Line Communication Channel

The Power Line Communication(PLC) is the technique which usually using power line as the signal transmission medium transmits voice, data. However, because the power line is designed to transmit power frequency alternating current(ac), it has a big difference with the traditional cable channels such as twisted pair, coaxial cable, optical fiber, etc. The complicated structure of distribution grid and the complex impedance makes the power line communication environment bad, such as many types of noise, multipath effect, signal attenuation, etc. Therefore, studying the characteristics of power line communication channel has great significance to the design of power line communication, operation maintenance, improving communication quality and speed. Reactive power compensator is an important component in the power grid. As a part of the impedance of power line communication channel, the reactive power compensator will affect the power line communication channel characteristics when it is put on and cut out. And the present research is carried out from the economic benefits of reactive power compensation for electric network, the optimal reactive power current, reactive power compensator improvement and other aspects. The study of impedance characteristics of PLC is stated most from the entire power load test, and the researches on influences of reactive power compensator on the characteristics of PLC channel has not been published in the literature. This article put emphasis on studying the influences of reactive power compensator on the characteristics of PLC channel.Firstly, the two models of power line and characteristics of PLC channel is analyzed and the commonly used reactive power compensators are introduced base on fully understanding of the working principle of reactive power compensator, structure and installation location in the grid. Then the impedance of WBMJ(Z) self-healing low voltage parallel capacitor is measured. Two kinds of modeling method of the high frequency model of reactive power compensator are put forward, which are the high frequency modeling based on lumped parameter circuit and the high frequency modeling based on modular ports behavior. The two high-frequency model of self-healing low voltage parallel capacitor is established with the help of MATLAB and 1stopt data analysis software. By comparing the model calculation value and measured value, rationality and validity of the model was validated. Finally the high frequency model are put into the PLC channel model and the influences of reactive power compensator on frequency response, multipath effect and attenuation of PLC channel is analyzed combined with the results of simulation analysis, and has acquired certain achievement, thus of reference value.The research achievements of this issue provides two methods to establish high frequency model of reactive power compensator and an effective means for the analysis characteristics of PLC channel. The laws obtained from simulation can provide references for science and technology personnel to design and maintenance of the PLC system and improve the quality and reliability of communication system. Results of this paper fill in the gap on the research on influences of reactive power compensator on the characteristics of PLC channel, and it was the base of further studying PLC.