Ice Formation Remote Control Technology on Overhead Transmission Lines and Its Validation with Allowable Simplifications of the Physical Processes Model
The description of the ice formation remote control technology on overhead transmission lines, which makes it possible to determine the length of the ice formation based on modes parameters measured at the substation, has been performed. The advantage of the proposed technology over existing ones is shown. It consists in the absence of the need to place additional distributed control devices along the whole length of the line. The mathematical proof of the technology using the "initial problem" method, which consists in simplifying the original problem by neglecting the secondary parameters and obtaining the exact solution of the simplified problem in the form of an analytical function, has been made. The principle of the new intelligent technology for ice formation length control in the ice melting intermittent duty is described. The principle consists in digital fixing of wire temperature, uncovered by ice, and the entire overhead line active resistance. The resistance depends on this temperature and on the length of the overhead line section covered by ice formation, that should be defined. According to these parameters of the melting mode and the initial data determined by the trial melting mode in preparation for the autumn-winter period, it is possible to determine the relative length of the ice formation at each current pulse. The end of the melting is fixed when the ice formation length becomes equal to zero. The assumptions made to simplify physical processes in technology development are outlined. The features of ice melting mode parameters measurement with the both direct and alternating current are shown. The procedure for processing of measurement results during the technology realization is described. It is shown that the use of certain integrals in solving the "initial problem" makes the problem better conditioned and allows excluding measurement emissions of the controlled mode parameters. To compensate errors caused by the accepted simplifications, assumptions are analyzed and recommended corrections are specified. It is planned on the basis of the described technology, in accordance with the work under the RFBR grant "Aspirants", to design a digital device or use the algorithm as an element of the digital substation providing the functioning of ice melting universal automatic system on all overhead lines branching from the substation.