Research On On-line Detection Technology And Inferring Methods Of High-voltage Circuit Breaker Mechanical Characteristics

High voltage circuit breaker (HVCB) as the important equipment in power system, the reliability and safety of HVCB have a vital role to entire electrical power system’s safe operation. The survey of CIGRE on power grid indicates that80%of HVCB’s failures are mechanical reasons and most of them are problems of operating mechanism. Charged detection as an important means of state detection can discover the potential failures of operating mechanism, so as to determine whether it should be repaired or replaced.First of all, the thesis introduces the basic structure of HVCB and analyses the common failure types of operating mechanism. Then common methods for HVCB mechanical fault detection are introduced and the mean used in this paper is confirmed which the combination of off-closing coil current detection and vibration signal detection according to the detection technique and applicable condition. The technology of off-closing coil current detection is more mature, but the vibration signal detection has certain difficulties due to the complexity of it.This thesis focuses on the design of the on-line detection device and simulation experiments on defects, so the last two chapters mainly expound them. The design of the on-line detection device includes two parts, respectively the hardware system and software system. The former is mainly for the selection of hall sensor and vibration sensor and the configuration of acquisition card and industrial computer. Software system can accomplish data collection and waveform displayed by Lab VIEW. Defects simulation experiments were conducted in the experiment center of Beijing Electric Power Research Institute and make sure four kinds of simulated defects with the higher incidence rate according to the results surveyed by Beijing Electric Power Company in recent years. When doing the experiments, collect the waveforms of off-closing coil current and vibration signals of simulated defects and normal condition then make software analyses about the test results that experiments and theoretical analyses have the same conclusion, at last confirm the standard waveforms and put in the fundamental database.