Assessment of the Performance of the Compressed Air Preparation System of the High-Voltage Air Circuit Breaker

Abstract

Air high-voltage circuit breakers, along with vacuum and SF6 circuit breakers, are widely used in electrical networks for switching operating and emergency currents. In air high-voltage circuit breakers, the extinguishing of the electric arc that occurs during the switching of operating or emergency currents by the circuit breaker is carried out under the influence of compressed air. Therefore, it is obvious that the operability of such switches significantly depends on the state of readiness of the compressed air preparation system, which imposes increased requirements on the technical means of compressed air preparation. The paper analyzes possible deviations from the normal operation of individual elements of the compressed air preparation system and develops a mathematical model based on it. A graph of the functioning of the compressed air preparation system has been formed, which takes into account all main possible situations in its operation. Using the mathematical apparatus of sequences according to expressions describing the graph of the functioning of the compressed air preparation system, a minimized description of its functioning has been obtained, according to which the structure of the corresponding device has been synthesized using an industrial element base. The use of the developed device allows to monitor the tightness of the compressed air preparation and accumulation tract, the correct operation of the pressure sensor and pressure measurement channel, the operation of the compressor and drive electric motor, which makes it possible to assess the system's performance and timely inform personnel about possible malfunctions. The device receives signals from the output of the compressed air pressure sensor, which measures the pressure value in the compressed air preparation path, and the voltage sensor located in the electric motor power supply circuits. The information coming from the sensors is processed based on the results of measurements in the state of readiness for switching, after the completion of switching and in the state of readiness after the completion of switching, on the basis of which a conclusion is formed regarding deviations in the operation of the compressed air preparation system.