Design And Implementation Of Signal Acquisition Hardware System For Multi-source Operating Conditions

Gas engines are widely used in the fields of energy,aviation and ships,and are the heart of large machinery.Among gas engine failure and shutdown factors,control system failures account for up to 44%,of which board card module and other failures account for 1/2 of control system failures.In order to provide data support for the fault prediction and health management of the control system,a multi-source operating condition signal acquisition system is designed in this thesis to collect the current and voltage signals generated during the operation of the control system and the surrounding environmental factor signals.Integrate and upload the collected electrical signals of the control system itself and environmental signals.The main research contents of this thesis are as follows:1.Multi-source signal acquisition hardware circuit design.A corresponding non-intrusive acquisition scheme is designed for the 6 types of signals: the signal acquisition of various environmental factors is carried out by means of sensors,and the designed board meets the following index requirements: the temperature measurement range is-10～80 ℃,device temperature measurement range-20 ～100 ℃,and the measurement resolution is 0.1 ℃;The light intensity signal accuracy is 0.01 Lux,which can collect light signals with a wavelength of 780-400 nm,that is,visible light signals;the sound signal sensitivity is-40 d B,and the measurement frequency range is20-20 k Hz;the magnetic field accuracy is 1 μT,and the range is ±2 m T;voltage and Ripple signal accuracy is 10 m V,maximum range is 30 V;current signal resolution is10 m A,maximum range is 30 A.2.The miniaturization design of the acquisition system board.In the design,the acquisition board can be put into the chassis for signal acquisition,and a single board can not only integrate each sensor element,but also ensure the miniaturization of the volume.It is mainly realized in two ways: one is to use a two-level board design,and the The acquisition board and the master control board are separated to reduce the volume of a single board;the second is to use miniaturized sensors to save board space as much as possible..3.Multi-source signal fusion processing.In view of the characteristics of multi-source signal data with many types and large quantities,the uploaded data is pre-processed by fusion processing.In order to ensure that the information can be restored after the host computer is unpacked,the signal is identified by writing a signal ID,and the specific data,information Type,sampling rate and time stamp information,signal identification and specific data are packaged according to the design format,and the data format is uploaded in a unified manner,which realizes real-time monitoring and accurate reflection of the overall operating status of the control system.4.Embedded signal processing.The control signal processing and communication of the whole acquisition system are designed and realized by embedded software.The embedded software part transplants the UC/OSII operating system.For the signal processing,firstly,a signal alarm mechanism is designed to realize the data compression processing when the signal is uploaded.Time stamp consistency between cards.Experiments are carried out on the test platform to verify that all 6 types of signal measurements can meet the index requirements,and the host computer can accurately receive signals in real time.