Research on acceleration phenomena with test equipment of simulating puffer type gas circuit breaker
The diagnosis was investigated by using the acceleration measurement for mechanical failure and degradation of a SF6 gas circuit breaker (GCB). The mechanical model GCB was fabricated to produce similar acceleration characteristics to a real GCB. The MEMS (Micro Electro-Mechanical System) sensor was adopted for the purpose of confirming its applicability with the well-established piezoelectric accelerometer. The acceleration characteristics of the model GCB was generally similar to the real GCB of 300kV class, except the high frequency component. The MEMS sensor application was feasible with some limitations. It was indicated a mechanical failure could be detected by the acceleration measurement.
Mechanical failure detection of circuit breakers
The mechanical condition of a circuit breaker, i.e., whether the unit is in normal or abnormal condition, has been evaluated using noninvasive diagnostics, together with signal processing and decision-making techniques. Test procedures involved obtaining vibration signals from transducers placed along the external surfaces of (and, under certain conditions, within the interior of) a circuit breaker. Using the method, quantitative assessment of a circuit breaker can be carried out for any operating condition. Tests of oil and sulfur hexafluoride circuit breakers, under both normal and abnormal conditions, were carried out. In all cases, the abnormalities was detected. >
Measurements for noninvasive mechanical diagnostics of power circuit breakers
Abstract The authors have developed techniques for assessing the mechanical condition of deenergized power circuit breakers based on noninvasive acceleration measurements during trip and close operations. An important element of the research has been the selection and implementation of measurement techniques that are capable of providing vibration data that are repeatable and sufficiently rich in information content to be useful for diagnostic purposes. The most critical aspects of the measurement methods, transducer location and attachment, as well as circuit breaker vibrational response and signature repeatability are addressed in this paper.