Method for extracting characteristic points of current curve of mechanical characteristic coil

The invention discloses a method for extracting characteristic points of a current curve of a mechanical characteristic coil, and belongs to the field of GIS circuit breaker fault detection.The method for extracting the characteristic points of the current curve of the mechanical characteristic coil comprises the steps that a curve slope method is adopted, and the characteristic points of the current curve of the mechanical characteristic coil are extracted by means of slope abrupt change caused by abrupt rising and abrupt falling of the coil when a circuit breaker conducts opening and closing actions; and the accuracy of the extracted feature points is improved by eliminating noisy points, so that the starting point and the ending point of the coil current are positioned. And comparing the extracted starting point and terminal point coordinates of the three phases with the starting point and terminal point coordinate ranges in a normal operation state, identifying abnormal feature points, removing the abnorm