Design Of Digital High Voltage Meter Based On FPGA And Microcontroller

With the continuous development of the society,electrical safety testing equipment has been widely used.The output signal of electrical safety testing equipment as the standard source input has a great impact on the data test results.Traditional measurement schemes require many kinds of equipment,complex test wiring,low work efficiency,high cost and low integration,which are difficult to meet the requirements of high voltage signal source evaluation.In view of this situation,based on the study of high voltage signal measurement,this paper designs a device for the comprehensive measurement of ac/DC voltage,current and frequency of the high voltage signal output by the electrical safety tester,which will have great significance for the comprehensive evaluation of digital high voltage meter equipment.This paper firstly designs a high performance system structure according to the function of the system,and then designs the system according to the designed structure.This system adopts two channels to measure separately,two channels are composed of high voltage attenuation circuit and current/voltage conversion circuit.Since the system measures high voltage,there must be a peripheral circuit that attenuates the high voltage and converts its output voltage to the input voltage range acceptable to the ADC.Because of the interference of various noises,input signals will be distorted in the process of transmission,so it is necessary to add a filter circuit after the high voltage attenuation circuit for filtering.The filtering effect by using hardware alone is not ideal,so this paper adopts the way of combining software with hardware to filter.In order to make better frequency measurement,it is necessary to add a shaping circuit after the filter circuit.Data collection is carried out by FPGA control ADC,and then the collected data is cached through FIFO and transmitted to SCM,which processes and displays the data.After testing,the digital high-voltage meter based on FPGA and SINGLE-chip microcomputer is used to separately measure the AC/DC voltage,current and frequency parameters of the high-voltage signal.The measurement results meet the set index requirements and achieve the expected function.