Networked Data Acquisition System Based On FPGA

Mechanical vibration signals acquisition (data collection and transmission) in mechanical equipment state monitoring and fault diagnosis system is a technical issue in a growing need to promote and enhance. This paper addressed this technical issue, made a contrast of different current machinery vibration signal data collection methods and collected data transmission methods and made an in-depth analysis. in accordance with the specific requirements of mechanical vibration signals, this paper propose a way to sample vibration signal with adjustable frequency which based on multiplexed conversion channel addressing in internal FPGA. Also addressed mechanical vibration signals features of large volume of data requirement of real-time, proposed a FPGA-based Ethernet to achieve the means of transmission. The design elaborated in this paper integrated control of data collection, data storage, data packaging and data transmission control in a single FPGA chip, and through hardware description language VHDL to achieve.The data collection and adjustable frequency solution: using state machine to control A/D conversion controller, the system could get higher speed and higher reliability; generating a multiplexed channel serial table in internal FPGA and through addressing the serial table, the system can to achieve an adjustable frequency data-sampling to a certain extent.Data storage solutions: in the internal FPGA achieve double-port RAM (FIFO) for the collection and storage of data, and complete Ethernet and TCP/IP protocols package synchronistically.In Ethernet communications, the design in this paper using a similar CPU small control system, complete the Ethernet communication control through the executive of instruction one by one.The reserve data cache unit: when the ethernet transmission is failed, the system turn to the coprocessor cache system, to complete the condition monitoring of the main equipmentsThe mechanical vibration signal data collection and data transmission proposed in the papers, made a great simplification of vibration signal acquisition strategy in the equipment condition monitoring and fault diagnostic system, also enhanced data acquisition efficiency, enhanced signal reliability, and greatly reduce the overall system cost. The general means of the data collection and data transmission is of a certain valuable reference for the same research in the field.