Technology Of 20kV Precisive Muti-Parameters High Voltage Meter And Prototype Development

As the requirements of safety tests on electronic devices are increasingly stringent,the quality of high voltage signals outputed by electrical safety test equipments needed to be accurately measured and evaluated to ensure the validity of the tests and the reliability of the results.Not only the measurements of effective value,average value and frequency of AC/DC high-voltage signal are required,the characteristic parameters of signal spectrum,distortion,ripple and transition process are also needed to be estimated.With weak of integration,unitary of function,and lack of frequency domain or transition process parameters measure ability,traditional high-voltage test equipments are difficult to meet the needs to assessing the performance of high-voltage signal source.In view of this situation,the methods to measure the time and frequency domain characteristic parameters of 50 V ~ 20 kV AC/DC high-voltage signals are studied in this dissertation.Based on the study,a muti-parameters high-voltage meter suitable for evaluating the performance of electrical safety test equipments is designed and developed.The main contents of this dissertation are as follows: Based on the research of key technologies such as high-voltage detection,current / voltage conversion,high-precision full-period data acquisition and signal processing,the high-performance overall architecture of the system are designed.The embedded hardware system based on FPGA+MCU for high-voltage meter,including high-stability and wide-fre quency range high-voltage detecter,high-precision linear-isolated current converter,precise frequency measurement module,digital control moudule and other circuits,are developed.High-voltage meter embedded system software based on FPGA+MCU is designed by using hierarchical and modular technology,and modules such as high-speed data acquisition and control,frequency measurement,on-line trasistion time measure and communication interface are implemented in FPGA;Control,signal processing,calibration,communication and GUI interface are implemented in MCU.After testing,the 20 kV high-precision multi-parameter high-voltage meter designed and developed in this project can achieve the measurements for RMS/average value of voltage and current of 50 V ~ 20 kV and 10 uA ~ 200 mA with the accuracy up to 0.3%.Moreover,it can measure the ripple factor,spectrum,distortion,and frequency of signal.It met the requirements of the project,passed the inspection,and has been selected by a number of scientific research institutes.