Research On Broadband Power Line Communication Channel Characteristics And Network Management Technology

Broadband PLC (Power Line Communication), as a new broadband accesstechnology, has becoming one of the hottest discussing problems recently. The researchon the PLC technology and application has profound practical value and theoreticalsense. Based on characteristics and structure of our countries power grid, the followingtechnical problems was discussed, such as the problem of broadband PLC access, theoptimization of OFDM (Orthogonal Frequency Division Multiplexing) and thebroadband PLC signal's influence on power quality etc. In addition, the test of mediumvoltage power line channel is finished for the first time, as well as the creation for themodel of medium voltage power line channel noise and attenuation. On the base of thenew technology of computer network and communication, a new broadband PLCnetwork management model and strategy is presented, in the meantime the broadbandPLC network management information model is designed and the problem of networkdevices management is discussed too.The influence of broadband PLC technology on the power quality and electricequipments is analyzed. For the 11 kinds of power quality perturbation, we computedand analyzed that if the broadband PLC signal has some influence on the power quality.At last we draw a conclusion that the broadband PLC carrier signal has no apparentinfluence on the power quality, as well as the electric equipments of electric powersystem.Based on the wavelet transform technique and OFDM modulation technique, aswell as the comparison of the characteristics and performance between modulationtechniques involved in the broadband power line communication, a techniquesubstituting multi-scale orthogonal wavelet for cosine function in OFDM for theoptimization design of system is proposed. This method can obviously improve theperformance of OFDM, overcome the deficiency of OFDM and enforce the syntheticanti-jamming capability of OFDM. In addition, by the emulation of OFDM technique, itproved that using the time internal could reduce both the ISI and the ICI, which seems tohave much meaning for the designs of the communication system.The medium voltage power line channel test is performed for the first time inour country. The impedance characteristics, noise characteristics, attenuation characteristicsand communication performance of medium voltage power line communication channel aretested, and the test data, test result and result analysis are presented.The methods of build the mathematical model of medium voltage power linechannel characteristic are discussed, and the transmission model is created based on thecharacteristics of medium voltage power line and practical cases. This modeling methodcan emulate the time domain characteristics and frequency domain characteristics ofbackground noise effectively.Based on the combination of Web technology and Mobile agent technology, abroadband PLC network management model and strategy is presented. In the meanwhile,the comparison between the conventional SNMP network management and mobile agentbased broadband PLC network management is made, form the two aspects throughputand response time. The conclusion proves that this model has good performance and thenetwork management strategy is feasible.The MIB and its information model of broadband PLC network management aredesigned. At last, the application cases of broadband PLC are given.