Application Of Multi-band Power Carrier Communication Technology In Medium Voltage Distribution Network

With the rise of the concept of intelligent distribution network,the demand for communication lines in power system is continuously increasing.A lot of manpower,material resources together with a huge amount of funds is needed in the building of new dedicated communication lines.Therefore,how to take advantage of existing distribution network lines to achieve power line data communication transmission has become the focus of technicians’ work.At present,power line carrier communication technology is mainly realized by G3-PLC technology.G3-PLC technology has the advantages of high reliability and strong anti-jamming ability within the prescribed range.However,this technology defines its scope of use with a fixed working frequency.That is to say,only within the prescribed range can the reliability requirements of communication be achieved.When faced complex power grid environment,different regions or different lines,communication fails frequently.As a result,the requirement of communication reliability can hardly be satisfied.Therefore,it is an urgent necessity to improve its bandwidth standard and channel capacity.Firstly,this paper studies the current situation of distribution network communication,and aims at finding the solutions to problems described above.Based on G3-PLC technology and OFDM(Orthogonal Frequency Division Multiplexing)technology,we independently develop a new generation of power carrier devices with multi-band and adaptive characteristics.The device mainly includes five parts: coupling circuit,analog front-end,transceiver front-end,physical layer processing unit,MAC/sink layer.The device can self-adaptively select the most appropriate operating frequency and channel bandwidth within the 7.8k Hz-10 MHz cross-band range to achieve effective transmission of information.Finally,the test of property and networking in the adaptive power carrier device is carried out.The experimental results show that the proposed multi-band adaptive technology can effectively increase the channel capacity,improve the reliability of data transmission,and meet the requirements of power system communication.