Development Of The Operation System For Centrifugal Pump Based On LORA Wireless Sensing Technology

The centrifugal pump has gradually attached great significance in daily life applications consonant with the rapid development of modern industry.In order to maintain the normal and efficient operation of the pump,we must monitor and diagnose the operational state of the centrifugal pump in time.Under severe circumstances of the operational environment,aging of traditional equipment,inappropriate operation and other factors,the centrifugal pumps are prone to mechanical breakdown.Once centrifugal pump has fault,it will not only harm the economic interest,but may cause casualties on site.Hence,many scholars have conduct a thorough research on the centrifugal pump monitoring system.Considerably,the staple of the system is wired monitoring,but subject to the equipment structure as well as the operation environment.This kind of traditional wired monitoring system has some drawbacks such as difficult to install,hard to wire,low tolerance for flexibility,etc.which greatly influence the development of remote monitoring technology of centrifugal pump.To address the above problems,this paper adopts Mahalanobis Distance diagnosis method,combined with LORA technology having embedded system;designing a set of centrifugal pump vibration state monitoring system with low power consumption,low cost,convenient installation,long transmission distance and reliable monitoring.In this paper,the main research content and the innovation points are as follows:(1)To effectively establish the vibration signal indicators of centrifugal pump,this paper selected 10 commonly used time-domain and frequency-domain indicators in vibration monitoring of centrifugal pump.Then the index parameter values under four diffirent working conditions of0.8Q_d,0.9Q_d,1.0Q_d,1.1Q_d were calculated respectively.Relief F algorithm was applied to remove redundant and irrelevant indicators.The first four most effective index parameters were selected to obtain an accurate index set of vibration signal monitoring,which is conducive to improve the accuracy of centrifugal pump vibration signal monitoring.(2)This paper accomplished the design and selection of the core control system,related chips and sensors in order to solve the problems of poor capability of wired monitoring system,insufficient processing capacity and short transmission distance of the current wireless monitoring system of centrifugal pump.On the system,STM32F412RGT6 is selected as the main control chip,LIS2DS12 accelerometer is selected to collect the vibration signal,using Lora module to transmit the vibration signal to the upper computer,which enables the system to have strong data processing ability and long-distance transmission ability.In light of the combination of Lora technology with the chip microprocessor module,the development cost of the system is reduced to a significant degree,and the vibration signal data can be stably collected,processed and transmitted.(3)Considering the problem of multiple index parameters in monitoring the vibration signal of centrifugal pump,which makes it difficult to determine the fault diagnosis of centrifugal pump uniformly.The parameter matrix set was obtained by measuring the three faults of centrifugal pump seal wear,cavitation and impeller wear and the indicators of vibration signals under the state respectively.Then,under the state of heath,the set of matrix and indicator parameters under the state of health were used to calculate the Mahalanobis distance value,Mahalanobis distance HI value and Mahalanobis distance normalized value.At the same time,the health threshold line of centrifugal pump was drawn.This calculation method is beneficial to eliminate the influence of different parameters and variables,and provides a certain quantitative analysis for vibration monitoring of centrifugal pump.Further it provides a more comprehensive foundation for fault diagnosis of centrifugal pump.