Measurement uncertainty analysis of periodic and random distortion in a high-voltage power supply

• Validate the effect of noise floor and frequency response. • Find total gain and evaluate uncertainty of transmission parameter. • Build the measurement equation of PARD test, present complete uncertainty analysis. • It is traced to national voltage standard through oscilloscope accuracy. This paper presents a novel method for estimating Periodic and Random Distortion (PARD) of high voltage (HV) power supply in constant voltage (CV) mode. The method emphasizes the evaluation and traceability of PARD measurements by considering the noise impact and the flatness of the measurement system. In addition, uncertainty analysis and budget calculations are provided based on a real test case involving a 600 V/2.6 A power supply. Experimental results demonstrate the good stability and accuracy of the method. This work fills a previously unexplored gap in PARD measurement uncertainty analysis.