Control of Overhead Power Lines with Unmanned Aerial Vehicles (UAVs)

The chapter describes the causes of overhead power line failures. It was noted that a significant number of power line emergency shutdowns occurs due to vandalism, such as the destruction of insulator strings, the theft of wires and support elements of power transmission lines, drafts on power transmission lines, etc. Thus, it is shown that monitoring the state of electric power facilities can significantly reduce the number of failures and prevent reasons for their occurrence. The concept of the state of electric power facilities is specified. It is proposed to use the registration of radiation: electric fields, electromagnetic fields, optical radiation. Registration of radiation can be performed at a distance from the object, which allows to use UAVs for monitoring. The authors structured and described the tasks in the energy sector, which can be solved with the help of UAVs. The classification of UAVs is shown. The classification of tasks in the energy sector associated with UAV types as the most suitable from the point of view of the tasks being solved is given.

Methods for one-sided determination of the location of power lines’ damage are of interest to all parts of the companies involved in the supply and redistribution of electricity. The advantage of one-sided methods for determining the location of damage by emergency mode parameters is the ability to determine the distance to the place of damage without transmitting information about emergency mode parameters from the opposite end of the line. Such methods are extremely promising from the point of view of reducing the costs of maintaining power lines. The section provides a classification of methods for one-sided determination of the location of damage. The mathematical model developed by the authors is described for one-sided determination of the place of damage to the power line by emergency mode parameters for the cases of single-phase, two-phase, three-phase short circuits. A technique for determining the location of damage of a line is disclosed.

Automation of damage location is based on the device and a set of algorithms. The device is built on the basis of a digital oscilloscope based on a computer (alarm recording). It allows to record and store information about the instantaneous values ​​of currents and voltages in three phases of all lines suitable for the substation. Further processing of instantaneous values, performed by the device—analyzer of fixed alarms, gives the desired set of mode parameters at the measurement point. The chapter provides a block diagram of the device. The choice of the moment of the beginning and the duration of the emergency analysis interval is described. The section shows the difference between the developed device and analogs. The main advantage of the developed device is the ability to analyze the modes according to secondary informative parameters obtained after processing the instantaneous values ​​of currents and voltages in the interval of analysis of the emergency mode. In this case, it becomes possible to use the criteria for determining the type of short circuit and the special phase. The block diagrams of algorithms of types of short circuits and a special phase are given. Also given the principles by which the location of a short circuit is determined.

The chapter presents the results that have received experimental confirmation of the operability of the method of one-sided determination of the location of damage. The analysis was carried out on data under operating conditions in 110 kV networks. Damage locations were determined by the emergency mode parameters of the power transmission lines of a number of emergency shutdowns of the lines recorded during the operation of the “TsPRS” and “Rekon-06BS” software and hardware systems, according to the method of one-sided determination of the location of the damage. The chapter shows a block diagram of the hardware-software complex “TsPRS”, describes the principles of the complex. It shows a block diagram of a unit for determining the location of the damage, which is designed to calculate the distance to the place of damage, and a unit for determining the parameters of the system, which is designed to calculate the parameters of the system. A step-by-step analysis of the operation of the device is given in the analysis of emergency blackouts of power lines in 110 kV networks.

The chapter contains analytical expressions for calculating strength of the electric and magnetic fields of the objects of the energy system. Such mathematical models are necessary to create a dependence of the behavior of these fields for various operating modes. It is separately noted that there cannot be ideal conditions for the propagation of electric and electromagnetic fields, therefore, the models provide for the absence and presence of objects in the zone of their operation are shown. Based on the complexity of mathematical dependencies in the description of the fields, assumptions are made that allow to simplify the development models. The chapter shows typical cases of the location of power lines. The complex values of the azimuthal and axial components of the electric field are recorded for them. Based on the calculation results, the electric field strength curves were constructed in the cross section perpendicular to the power transmission lines at different distances.

The chapter is devoted to the protection of equipment of electrical substations and power lines from the damaging effects of lightning. One of the negative phenomena on electrical equipment is the presence of a corona discharge. The chapter notes that corona discharge can be one of the stimulating conditions for lightning. A high-voltage experimental bench and a methodology for studying processes related to the advancement of the lightning leader channel to the ground and the “choice” of the place of impact are described. The results of experimental studies of breakdown processes in the presence of a corona discharge at the tops of grounded rods are presented. Lines of equal electric field strength are constructed for various cross sections with different rounding radii. Conclusions are drawn about the dependence of the influence on the probability of damage to the corresponding grounded electrode by a high-voltage discharge in the presence of a corona discharge on it and without corona discharge.

The chapter is devoted to the physical causes of the corona discharge in the elements of the electric power system. The most significant negative consequences of a corona discharge are the loss of electricity, as well as a decrease of its quality due to the appearance of higher harmonics. The cause of this discharge is the presence of an electric field with a significant gradient. Therefore, the section simulates electric fields in the presence of rods with rounded vertices and in the presence of curved interface surfaces. Conclusions are drawn on the influence of the geometry of rods with rounded vertices at the level of maximum electric field strength. A combined technique of mathematical modeling of electric field amplification on the rounded vertices of very long cylindrical rods is given. The calculation of the amplification of the electric field at the tops of long cylindrical rods is carried out.

The chapter contains materials on elucidating the influence of the shape of the top of the rod electrode and the value of the applied electric field strength on the presence and value of the corona current on top of the grounded electrode. Physical modeling was used. The purpose of these experiments was to establish a correlation between the results of physical and mathematical modeling of electromagnetic processes during the development of corona discharges in order to verify the adequacy of the description by a mathematical model of the processes of the appearance of the corona, as well as their degree of intensity, due to the value of the corona current. The results of physical modeling of electromagnetic processes during the development of the corona on rod electrodes with tops of various shapes are presented, using which mathematical models of the processes of corona formation on the tops of rod electrodes are constructed.

The chapter shows the dependence of quality indicators on the corona discharge on conductive elements. The dependence of the presence of higher harmonics in the electric network and corona discharge is noted. The direction of the search for the location in the space of the corona discharge was selected for the possibility of combating it. The direct determination of the presence of a corona discharge by electrical parameters (current shape and voltage shape) is problematic for making measurements directly on the lines. Therefore, other types of corona discharge factors were analyzed. Corona discharge consumes energy, which is converted into other forms of energy (or chemical compounds), and remains in the space surrounding them. The authors drew attention to acoustic noise in electrical installations and associated them with corona discharge. A laboratory bench was created and the connection of acoustic noise and the presence of corona discharge were confirmed. The chapter presents the results of the experiment. Acoustic noises were decomposed according to the Fourier transform and the spectral groups were determined that are characteristic of a corona discharge depending on the voltage at the rods. A three-dimensional acoustic model of the corona discharge was constructed, which made it possible to create an algorithm for searching for the source of the corona discharge.