A Power-Supply Unit for a Measuring Sensor Positioned on an Overhead Power Line
Mikhail O. Skripachev, E. A. Krotkov, Ya. V. Makarov · Russian Electrical Engineering · 2022
Abstract When placing sensors for measuring the physical parameters of high-voltage overhead power lines (OPLs) directly on a high-potential wire on an overhead line, it is necessary to provide uninterrupted power supply to the sensors. A brief review of publications devoted to power-supply units for measuring sensors installed on an overhead-line wire has revealed the advantages and disadvantages of engineering solutions for such units. The analysis performed for relevant engineering solutions has shown that the method of taking power from an overhead-line wire with the use of a current transformer requires for further investigations. The advantage of this method consists in its autonomy, while its disadvantage is the need to stabilize the voltage across the load within a wide range of change in the primary current of the overhead line. Therefore, developing a sensor power-supply unit that would take power from an overhead-line wire, providing the measuring sensor with a stable input voltage in the entire range of currents in the wire, is important. A principle and an operation scheme for the power-supply unit are proposed, using the example of which the physical and numerical simulation has been performed. The analysis of the current and voltage oscillograms obtained using a laboratory-scale prototype of the power-supply unit has confirmed the fact that it is quite possible to stabilize the voltage level of the measuring sensors in normal and emergency overhead line modes. When the laboratory prototype of the power-supply unit is switched to the emergency primary current, the voltage curve has an aperiodic character with a settling time less than the industrial-frequency period and does not reach any values hazardous for the electronic part of the power-supply unit. The power-supply unit designed according to the proposed principle is a quite versatile device and can be used for reliable power supply for measuring sensors installed on the wire of an overhead power line.