The data compression algorithm based on the gearbox configuration is based on the physical structure of the gearbox and the shaft speed signal, extracts the period domain data containing complete operation information from the discrete vibration data in the time domain, and provides a concise and effective data source for fault analysis.
The internal structure of the gearbox determines the installation position of the vibration sensor, and the position of the sensor directly affects the effect of fault diagnosis. Therefore, it is very important to master the internal structure of the fan gearbox. Through the frequency domain analysis, we can get the rotation frequency of each shaft, the damage frequency of bearing and gear, the corresponding amplitude of higher harmonic, and the energy distribution of the signal. These analysis results provide the basis for judging whether the gearbox has a fault, analyzing the location of the gearbox fault and judging the severity of the fault. Therefore, considering the physical structure of gearbox provides an effective method and powerful basis for fault detection.
Due to the different types of units, there are great differences in the internal structure of the gearbox. According to its transmission form, it can be divided into fixed shaft gear transmission, planetary gear transmission and their combination. At present, the common gear box structure includes one-stage planetary and two-stage parallel structure gear box, two-stage planetary and one-stage parallel structure gear box and compound planetary gear box. It mainly consists of ring gear, sun gear, planetary gear (generally 3 or 4) and parallel gear.
The internal structure of gearbox can be divided into gear, shaft and bearing according to its components. The data including complete vibration response information is extracted mainly based on the physical parameters of gear. In the planetary stage structure, the number of teeth of each gear and the number of planetary teeth are the factors that affect the magnification ratio of shaft speed; in the parallel stage structure, the number of teeth of the big gear and the small gear are the factors that affect the magnification ratio of shaft speed.