Research On Fault Diagnosis Technology Based On Vibration Signal Processing

In the process of the oilfield development,the pressure between the oil reservoirs will decrease continuously,which leads to the increase of the cost and the difficulty of the oil development.Usually,the water will be injected into the oilfield to fill up the pressure between the oil reservoirs to ensure the regular production of the oilfield.Water-injection pump is the main equipment for the oilfield water injection,and the pump's safety and steady operation is the key point to ensure the high efficiency of the water injection process.Therefore it is very necessary to carry out the research on the fault diagnosis for the water-injection pump.Considering the condition of the low level of intelligence,weak real-time processing capacity,low fault diagnosis accuracy and excess dependence on judgment of artificial experience for the current water-injection pump monitoring system,this paper build a set of water-injection pump conditions and fault diagnosis system based on the vibration signal.The scheme design consists of three modules: the data acquisition module based on the three-axis acceleration sensor ADXL345 and microprocessor STM32F030;the data processing and transmission module based on the 433 MHz wireless transparent data transceiver module and microprocessor STM32F407,and the upper PC module for the analysis and display of the working condition and fault diagnosis for the pump.For the processing and analysis of the vibration signal,the acquired acceleration signal is firstly converted to a displacement signal,and due to the non-stationary characteristics of the vibration signal,the displacement signal is processed using the Empirical Mode Decomposition method to reduce noises,after which the frequency spectrum of the vibration signal can be obtained with the method of envelop analysis.Due to the fact that different faults of the water pump can produce different characteristic frequencies,the frequency spectrum gained from using the envelop analysis method can be used in the analysis of the water-injection pump fault diagnosis.Finally the field experiments prove that the signal acquisition and processing and the fault diagnosis of the water-injection pump based on the vibration signal can be realized using the system above.