Research And Design Of Frequency Module And Temperature Module For Scopecorder

In the production process of power electronics industry,we often need to monitor,analyze and record the changes of frequency,rotation rate,temperature,voltage and other physical signals of products in real time,which is helpful to ensure the quality and safety of products.Traditional instruments can not meet the needs of acquisition and processing of multiple physical signals,display and analysis of waveforms of multiple physical signals,and long-term recording of multiple physical signals.The scopecorder developed in this paper is a comprehensive electronic measuring device which can support waveform measurement,analysis and recording of multiple physical signals.It can effectively meet the above requirements.Among them,the pluggable module is one of the main core parts of the scopecorder to realize the acquisition and processing of multiple physical signals.This paper mainly studies the design of pluggable modules to achieve acquisition and processing of high-resolution frequency and frequency-related multiple physical signals,as well as acquisition and processing of multi-channel wide range temperature or small voltage signal.The main research contents are as follows:1.Based on the overall scheme of scopecorder,this paper designs high resolution frequency module and multi-channel temperature and voltage module by choosing appropriate measurement methods according to the demand.Combining the time delay method with the direct period measurement method,this paper uses TDC + FPGA scheme to design the high-resolution frequency module.In this paper,a multi-channel temperature and voltage module is designed based on the thermocouple temperature measurement method.2.Design of high-resolution frequency module.The analog channel circuit is designed to convert the measured signal into square wave signal.A high-resolution measurement module is designed by using TDC + FPGA scheme,through which high resolution frequency measurement(?625ps)is realized.The basic parameters measured by the high-resolution measurement module are input into the multi-physical quantity operation module.After calculation,multiple physical signals related to frequency can be obtained,and the measurement of multiple physical signals related to frequency can be realized.3.Design of multi-channel temperature and voltage module.A 16-channel temperature and voltage scanning module is designed,which combines with the control of FPGA for polling sampling.Therefore,16-channel temperature or voltage measurement are realized.The 16-channel temperature and voltage scanning module not only supports 8 types of thermocouples,but also has the function of detecting the break of the thermocouple and measuring the temperature at the cold end.An analog channel circuit is designed to adjust the thermo-electromotive force or small voltage signal converted by the thermocouple to an appropriate voltage and then enter the ADC sampling.According to the voltage-temperature conversion algorithm,the voltage value is converted to the corresponding temperature value,and a wide range of temperature measurement(-200?~1800?)is realized.Finally,the test and verification results show that the high-resolution frequency module and the multi-channel temperature and voltage module meet the design requirements.