Research On Key Technologies Of Smart Bridge For Medium-low Voltage Power Line Interconnection Communication

The interconnection between medium-voltage and low-voltage power line channelswill be able to effectively solve the transmission problem of electricity informationduring the process of rural power grid intellectualization construction. However, there isno good solution at home and abroad currently. In this paper, the research on the keytechnology of smart bridge for the medium-low voltage power line interconnectioncommunication has been deep conducted. Significant research results have beenachieved.Firstly, experiment system was built to test the bridging performance of the simplepassive bridge. Then the noise and attenuation characteristics of channel bridging weretested in depth. The reasons that affected the performance of the bridge were analyzed.Aimed at the problems of the passive bridge, the general scheme of smart bridgeand hardware circuits of the main units were designed. Then the principle and function ofeach unit as well as the overall workflow of the smart bridge were analyzed in detail.Since the slow time-varying characteristics of the channel, a real-time channelequalization algorithm based on SIFT fast power spectrum estimation and decisionfeedback was proposed. In this algorithm, the real-time channel receiving spectrum wasestimated at first. Then the receiving spectrum of the current channel combined with theprevious time channel characteristics were used to estimate the current channelequalization value and a closed-loop feedback link was constituted. The algorithm wastested through simulation platform.Finally, in order to effectively overcome the impact of noise in the channel, animproved algorithm based on autocorrelation de-noising and decision feedback wasproposed. Simulation results show that the algorithm effectively improves theperformance of medium-low voltage power line channel interconnection communication.