Studying On The Vibration Monitoring System Based On DSP And Its Application In The Rotor Dynamic Balance Test

With the development of economy and continuous improvement of technology，mechanical and electrical equipment is becoming more and more large，precise, rapid andautomatic. In the mean time, the proportion of equipment maintenance costs is become higherin the whole life cycle. It is necessary to put forward higher request in condition monitoringand fault diagnosis technology in order to reduce the loss of equipment by accidents.Researches show that mechanical vibration is one of the main reasons which cause theequipment fault. Therefore, vibration monitoring system based on DSP was researched anddeveloped in this paper, following the research of general characteristics in equipmentvibration. Through real-time data acquisition and analysis for vibration characteristics, thefoundation of fault diagnosis is established.Coordinated working mode constituted by upper and lower computers is used in thissystem. DSP is used as the core of control and calculation in lower computer, according to thecharacteristics in vibration signal and the requirements of testing, and also for the expansionof the system. TMS320F2812 is used to collect signals, including 2 channels speed signal, 8channels digital signal and 16 channels vibration signal, and then used to do real-time analysisin time domain and frequency domain for the vibration signal. PC is used as upper computerto receive real-time sampling information and characteristic data from the lower computerthrough USB, and to make further signal analysis and processing by LabVIEW.The following three main parts of work are made in the paper:1) The development of monitoring platform based on DSPThe acquisition of equipment state parameters is accomplished through the design of theperipheral interface circuit, including analog input interface circuit, frequency input circuit,digital input and output circuit. Fast digital filter on the chip and FFT are realized throughhardware structure and instructions system of the DSP. The problem of large data transmissionin real-time is resolved by the high-speed USB, which is based on FT245.2) The data analysis and processing in the upper computerFurther store, reading, analyses, processing and display are made for the data from thelower computer through USB, as the powerful data processing ability and visual interface inLabVIEW. The aim of fault diagnosis can be achieved through vibration state information,which can be reached by spectrum analysis, time domain analysis and axis centric pathanalysis.3) Dynamic balance test of the rotorThe test is conducted on the ZT-3 analog test-bed. Analyses and processing are made forthe vibration signal, which collected by the vibration monitoring platform, through LabVIEW.And performance parameters are extracted out. Finally, the quality and position of unbalancemass are figured out through the three aggravating method. The acquisition, analyses and processing of vibration and speed signal are realizedthrough the vibration monitoring system based on DSP by combined hardware and software.The highest frequency of signal acquisition is 4kHz, which can meet the need of mechanicalvibration monitoring. The correctness and practicability of vibration monitoring platform arevalidated through the rotor dynamic balance test.