基于频谱法的航空起动发电机故障检测与诊断

对航空直流起动发电机的电枢电流波形进行频谱分析可有效地对电机的故障进行检测和诊断.由于电机在运行时其转速是变化的,而电枢电流的纹波信号与电机转速成正比,若对电流进行定时采样,则其频谱会散布在很宽的频率范围内,使频谱特征模糊化,难于利用频谱特征进行故障检测和诊断.采用与转速同步的电流采样方法,得到的频谱称为"阶比谱",在阶比谱上,频谱成分是单一的,因此容易用它来进行故障检测和诊断.文中对起动发电机进行了实验,对线圈短路、绕组元件与换向片开焊、相邻导体短路和转子偏心等四种故障成功地进行了检测和诊断. 

Fault detection and diagnosis of aero-starter-generator based on spectrum analyses

Faults in aero starter generator by analyzing the spectrum of motor armature current could be effectively detected and diagnosed. Because rotation speed was fluctuating during the operation of the motor and the ripple of current was proportional to the speed fluctuating, if the sampling period of current was constant, the spectrum of current would spread over a wide range. The fuzziness of spectrum characteristics made fault detection and isolation difficult. While using sampling which was synchronized with the rotation speed this problem could be solved based on analysis of the resulted order ratio spectrum. Experiment on fault detection and isolation was conducted. Four faults (broken coil, broken connection between coil and commutator, short circuit between two neighboring conductors and eccentricity of the rotor) was successively detected and isolated using the proposed method.