The change in voltage of zero sequence during the signaling on power network 0.38 кV

The location of agricultural enterprises in areas with less developed communication network makes it promising to develop methods of telecommunica-tion by power wires directly feeding electrical instal-lations. Therefore the Department of Electricity Supply of Kostroma State Agricultural Academy has developed the method for controlling electrical consumers in the power network, by which at the beginning of the line a secondary winding of a sin-gle-phase transformer is inserted into the gap of neutral wire, the primary winding of the transformer is fed with the phase or line voltage. At the end of the line reacting body which at the set change of phase tension carries out the programmed actions is established, for example, it gives the signal of inclusion or shutdown. Signaling is in such a way based on the change of potential of a zero wire, also changeable at the connection of asymmetrical single-phase loading. For the purpose of studying the influence of asymmetrical single-phase load of signals the control transferred on a power network theoretical research on the example of system of power supply of three wells was conducted. Math-ematical model of system was made with the use of the method of phase coordinates, the results were processed in the STATGRAPHICS Plus program. Technical realization of the way of management of consumers of electricity on a power network was presented in the study with application of the meth-od of phase coordinates mathematical model of the system of power supply of three wells in which sig-nals control were transferred on a power network by means of the change of tension of zero se-quence was made; the choice of tension given on primary winding of the transformer used for signal-ing on a power network at connection with sym-metrical single-phase loading was reasonable; and also the possibility of change of the operating value of current in zero wire and current corner in zero wire independently from each other was proved.