Kozlovskyi O. Improving the efficiency of overhead power lines operation of distribution electric networks in the conditions of ice formation

Object of study: the process formation of glaze and rime deposits on overhead power lines. Subject of study: electrical and thermal parameters of glaze and rime deposits on the wires of overhead lines of distribution electric networks. The purpose of the thesis: reduction of failures in power supply on the basis of the introduction of an information system for monitoring the state of the overhead power lines of distribution electric networks in the case of ice-wind phenomena on the basis of the developed methods and technical means of their implementation. Methods of research: the work is based on a systematic approach to conducting theoretical and experimental studies based on the use of the theory of heat and mass transfer, the theory of differential and integral calculus, solid-state modeling methods, mathematical methods and computational experiment in heat transfer problems, classical methods of measuring electrical and meteorological parameters during the experiment and statistical theory of processing the results of the experiment. Computer modeling was designed in the SolidWorks software environment. The practical significance of the obtained results of work for the electric power industry is the development of an algorithm for predicting the time of occurrence of glaze and rime deposits. The electronic model of the ice formation measuring transducer was created. It was used in the development of the microcontroller unit and the measuring transducer of the information system for monitoring the conditions of overhead lines in ice formation state. The recommendations on increasing the efficiency of operation of overhead lines of distribution electric networks in conditions of ice formation have been developed. The scientific novelty of the obtained results is as follows: for the first time, the use of the artificial cooling of the controlled wire section as the primary informative parameter of the start of ice formation is scientifically justified, which let to increase the accuracy of methods for predicting the formation of glaze and rime deposits; for the first time, has been developed a method for predicting the formation of ice on the wires of overhead transmission lines, which consists in the control of change of the intervals duration during cyclic artificial cooling of the monitored section of the wire at a constant speed, which reduces the time for the operating personnel to take decisions of protection measures conducting for overhead lines; the method for determining the appearance of glaze and rime deposits has been further developed, which, unlike the known ones, takes into account the parameters of the overhead power lines wire, which allows reducing the sizes of primary measuring transducers and at an early stage to fix the start of ice formation by monitoring the electrical resistance between the electrodes formed from the wires of the upper layer of uninsulated wire section of overhead transmission lines; in the thesis was developed a generalized mathematical model of the measuring transducer operation for the information system for monitoring the state of overhead transmission lines in conditions of ice formation, which allowed to take into account the parameters of the environment during its thermal analysis. The results of this work were implemented in PC "Kirovogradoblenergo" and are used in the educational process of the Department of Electrical Engineering Systems and Energy Management of the Central Ukrainian National Technical University in courses of lectures and laboratory works.