Power frequency communication synchronous detection method and device for industrial power grid

Abstract

The invention discloses a power frequency communication synchronous detection method and device for an industrial power grid, belonging to the technical field of power system network structure and communication. The power frequency communication synchronous detection device for the industrial power grid is formed by connecting a master station device and a telecommunication terminal of a distribution transformer end to a high voltage transmission line of a substation; down driving equipment in the master station device firstly sends synchronous information based on M sequence coding before sending down data information; when the communication terminal receives a signal, a composite signal is formed according to modulation coding, and the synchronous detection is realized on the composite signal through short-window Morlet complex wavelet transformation; after the synchronous detection is successful, the communication terminal can carry out data demodulation; because the synchronous information can be enhanced and does not need a detection threshold, the invention adapts to the severe channel environment of the industrial power grid and can utilize a house transformer of the substation as a signal modulation transformer, thereby greatly facilitating the application of power frequency communication in the industrial power grid.

Description

technical field [0001] The invention belongs to the field of power system network structure and communication technology, in particular to a method and device for synchronous detection of power frequency communication used in industrial power grids. Background technique [0002] In the industrial power grid, high-power motors need to be effectively managed. The characteristic of the power line power frequency communication method is that it can realize long-distance transmission across the transformer station area. Since there is no need to add additional equipment to the high-voltage line, the cost of the system equipment is low, and there is no communication service. If it can adapt to the channel environment of the industrial grid, it is very suitable as a data transmission channel for the remote monitoring system of high-power motors. [0003] In industrial power grids, such as figure 1 As shown, the main station equipment, pumping motor D and the remote communication t...

AI Technical Summary

Problems solved by technology

Before sending the downlink data information, the downlink driving device in the master station equipment first sends the synchronization information based on the M-sequence code. When the communication terminal receives the signal, it forms a composite signal according to the modulation code, and performs a short-window Morlet complex wavelet transform on the composite signal. The energy parameter calculation is combined with the characteristics of M-sequence coding to realize synchronous detection. After the synchronous detection is successful, the communication terminal can perform data demodulation. Since the synchronous information can be enhanced and there is no need for a judgment threshold, due to the limitations of site conditions and operation management, in the It is very difficult to install a special power frequency communication modulation transformer in the substation, and the downlink voltage distortion can only be generated through the voltage used in the substation; due to the limitation of the variable capacity used, the voltage distortion signal is weak, and at the same time, the power grid interference generated by the oil pumping motor and other equipment Very strong, the power frequency communication method applied to civilian grid residents is difficult to ensure communication performance in industrial power grids; power frequency communication terminals are difficult to distinguish voltage distortion signals from substations from grid interference, synchronous detection cannot be realized, and data communication cannot be carried out

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